Diagnostic and Concerning Features of Obstetrical Ultrasound

Obstetrical Ultrasound

Is the evaluation of changes and alterations occurring in the fetus and the pelvic cavity of the mother during pregnancy, which includes embryogenesis and structural changes usually of the size of the pelvic cavity. These diagnostic and concerning features are seen during the first trimester of the gestation.

Diagnostic Features that Conforms non-viable Pregnancy

1. Crown to rump length greater than 7mm with no evaluation of embryo confirms non-viable pregnancy.
2. Mean sac diameter greater than 25mm with no visualization of yolk sac and embryo confirms non-viable pregnancy.
3. If the embryo and cardiac activity are not seen after:

•    Two or more weeks of the visualization of the gestational sac
• 9 to 10 days following visualization of gestational and yolk sac

Concerning Features that are not Diagnostic Features of non-viable Pregnancy

1. The crown to rump length less than 7mm favors viable pregnancy.
2. Mean sac diameter less than 25mm will result in viable pregnancy.
3. An empty amnion sign. 
4. Double belb sign.
5. Misshapen gestational sac (irregular, thin hypoechogenic peripheral rim)
6. Large amnion relative to the embryo.
7. Dislocation of the gestational sac.
8. Small gestational sac relative to the embryo, the condition is termed as oligohydramnios
9. Abnormal heartbeat rate, lower than 90bps before 6.3 weeks of gestation and lower than 110bps greater than 7 to 10 weeks of gestation, the condition is termed as bradycardia.
10. No embryo with cardiac activity is seen after 6 weeks of gestation or last menstrual cycle.
11. Chorionic bump.
12. Abnormal appearing  

Endocarditis

Endocarditis is a bacterial or fungal inflammation of the inner layer of the heart, the endocardium, resulting in the formation of an adherent mass of thromboitic debris and organisms, termed as vegetation. It normally involves the coronary heart valves, the interventricular septum, the mural endocardium, cordae tendineae or the surfaces of the intracardiac gadgets. It's miles continually a severe infection and, if left untreated, will result in demise.

What Causes Endocarditis?

Predisposing factors

• Congenital heart disease: Such as bicuspid aortic valve, hypertrophic subaortic stenosis, calcified aortic valve disease, VSD, coarctation of aorta or patent ductus arteriosus
• Rheumatic Coronary disease: So as of sequence mitral regurgitation, mitral stenosis, aortic stenosis, aortic regurgitation
• Prosthetic valves

Organisms

• Enterococcus fecalis is found in perianal and fecal bacterial flora. It can cause infections more commonly in older men with the prostatic disease while in women with genitourinary infections.
• Staphylococcus aureus is responsible for acute endocarditis and originates from skin infections, abscesses or intravenous lines.
• Streptococcus viridians are a common cause of periodontal infections and are commensals in the upper respiratory tract. They may enter the blood stream on chewing, teeth brushing, or dental extraction.
• Postoperative endocarditis follows cardiac surgery and affects native or prosthetic valve. The most common organism is Staphylococcus epidermis.
• Fungal infections ( Aspergillus, Candida ) may attack previously normal or prosthetic valves, usually affects drug addicts and immunosuppressed patients.

Types of Endocarditis

   There are several ways to classify endocarditis. The simplest classification is based on the cause: either infective or non-infective, depending on whether the microorganism is the source of inflammation or not. The infective endocarditis is further subdivided into following subtypes:

Acute infective endocarditis

A highly virulent organism such as Staphylococcus aureus is responsible for causing an acute infective endocarditis. They can cause severe destruction of valve resulting in acute valvular regurgitation. Intravenous drug users are at very risk of endocarditis because numerous needle punctures give aggressive staph bacteria many opportunities to enter. If untreated this form of endocarditis can be fatal in less than six weeks.

Subacute infective endocarditis

Subacute infective endocarditis is caused by organisms of low virulence such as Streptococcus viridian and Streptococcus epidermidis that normally live in mouth and throat and almost always occur in patients with a pre-existing valvular abnormality. This condition has more chronic course, the resultant infection tends to progress somewhat more slowly and it usually is less likely to cause septic emboli than acute endocarditis. If untreated, it can worsen for as long as one year before it is fatal. 

Prosthetic Endocarditis

Prosthetic endocarditis is a serious infection with potentially fatal consequences, it can arise early or late after surgery. The timing of the infection reflects a different pathogenic mechanism that, in turn, influence the pathology and clinical manifestation of the infection. The common organism responsible for the prosthetic endocarditis is Staphylococcus epidermidis. This produces myocardial abscesses and damage to the conduction system.

Medical features of infective endocarditis 

• Features of contamination: Fever, night time sweats, fatigue, arthralgia, myalgia, weight reduction.
• Cardiac capabilities: Signs and symptoms of an underlying heart ailment, a cardiac failure because of valvular destruction, new or converting murmur.
• Functions of embolism: First time may additionally gift with embolic functions including stroke, pulmonary or myocardial infarction, extreme limb ache.
• Functions of immune vasculitis: Splinter hemorrhage, petechial hemorrhage, clubbing, janeway lesion.

Inspections of infective endocarditis

Following are a number of the powerful investigations to diagnose infective endocarditis:

1. Blood culture: It's far positive in approximately 95% of instances and negative in 5% cases.
2. ECG: This will display myocardial infarction or conduction defects,
3. Echocardiography: Is the important thing research for the detection of vegetations, valve harm, and the abscess formation.
4. Chest X-ray: This can indicate cardiac failure or pulmonary embolism in right-sided failure.
5. Serological assessments: It may include tests for immune complexes. 
6. Urine evaluation: Proteinuria may also occur and microscopic hematuria is constantly gifted.

Thalassemia

Thalassemia is a group of a genetic disorder of hemoglobin synthesis characterized by a decreased synthesis of globin chain. It is a type of microcytic anemia which affects blood functioning. Two alpha and two beta chains of globin polypeptide combine with haem to form hemoglobin. If synthesis of globin is reduced it will lead to decreased hemoglobin (anemia). Anemia is a condition in which body does not have enough normal, healthy red blood cells due to the destruction of erythrocytes at the massive rate. It is inherited meaning that at least one of your parents must be a carrier of the diseases. If both of your parents are carriers of thalassemia, you have a greater chance of inheriting a more serious form of thalassemia.
Several types and subtypes of the thalassemia exist, and symptoms depend on the type of disorder.

Types of thalassemia

• In normal (homozygote) both polypeptide genes are normal and produce normal beta polypeptide chains in normal quantity.
• In heterozygote conditions, one gene is abnormal and fails to perform its function but the normal gene produces enough beta chain to maintain hemoglobin level about normal. Such condition is referred to as Beta-thalassemia minor. 
• In thalassemia conditions a patient's blood contains abnormal homozygote-beta chain, both genes are abnormal and do not produce beta polypeptide chain. Such condition is called Beta thalassemia major. 
• Decreased beta chain results in unbalanced polypeptide chain production. Beta chain production is impaired or stopped while alpha chain production is normal. Alpha chain will combine with any beta chain available while remaining alpha chains combine with gamma chains to form hemoglobin F ( Fetal hemoglobin). The free alpha chains precipitate within the red cells resulting in the damage of the cell membrane and making them susceptible to phagocytosis by the reticuloendothelial system.

Beta thalassemia

Some of the most common subtypes of the Beta thalassemia are:

• Silent carrier, which usually does not cause symptoms
• A beta thalassemia trait, which causes mild anemia
• Thalassemia major ( cooley's anemia) which causes severe anemia, stunted growth, and an abnormally large spleen (splenomegaly)

Beta thalassemia major

It is a subtype of Beta-thalassemia and much more diverse than the alpha-thalassemia syndromes due to the diversity of the mutations that produce the defects in the beta globin gene. Individuals who have beta thalassemia major are usually homozygous for one of the common mutations or heterozygous for one of the common mutations. Both lead to an absence of beta globin chain production.

Symptoms of Beta-thalassemia major

Children affected by the Beta thalassemia major have following common symptoms:

1. Growth retardation
2. Intermittent infection
3. Severe anemia
4. Bone marrow hyperplasia causing bossing of skull
5. Hepatosplenomegaly

Investigations

Investigations are involved:

1. Blood picture
2. Serum ferritin high serum iron binding capacity saturated
3. X-ray of cranium: Indicates hair on end look.
4. Hemoglobin electrophoresis: Indicates a boom in fetal hemoglobin (HbF) 

Treatment

Following are some of the effective treatments for the Beta-thalassemia major.

1. Splenectomy
2. Bone marrow transplantation
3. Blood transfusion every 4-6 weeks

Alpha thalassemia

Some of the most common subtypes of the alpha-thalassemia are:

• Silent carrier, which does not cause symptoms
• An alpha thalassemia trait that can cause mild anemia
• Alpha-Thalassemia major is the most severe type. A developing fetus with this type of thalassemia needs a blood transfusion while still in the womb to survive.
• Hb H disease, which causes mild to moderately severe anemia, and an enlarge spleen ( the organ that removes worn-out old red blood cells )

Alpha thalassemia

It is characterized by an inactivation of alpha globin genes, which results in a relative increase in nonfunctional beta globin or gamma globin tetramers and subsequent cell damage. There are four alpha genes. If one gene is deleted there is no clinical effect and if two alpha genes are deleted there is mild hypochromic anemia. If all four are deleted, the baby is stillborn ( hydrops fetalis ).

Symptoms of Alpha thalassemia

Patients with the more severe type of alpha thalassemia can have:

1. Slight to extremely pale skin, slight jaundice, a swollen or large abdomen
2. Nerve problems or paralysis
3. Exercise intolerance
4. Coronary heart murmur (atypical sounds inside the heart)
5. Enlarged organs
6. Frequent infections

Treatments

• Hydrops fetalis - none
• Hemoglobin H - as for thalassemia major
• Avoid iron therapy
• Folic acid if required 

Functions of Kidneys

Kidneys are two bean-shaped organs that perform several vital functions besides formation of urine. By excreting urine, kidney plays the principal role in homeostasis.
They reside against the back muscles in the upper abdominal cavity. They reside in opposite to each other on both aspects of the backbone. The right kidney sits a little bit lower than the left to accommodate the liver.
The kidneys are multi-functional powerhouses of activity when it comes to components of the urinary system. Some of the core functions of the kidneys are detailed below.

ROLE IN HOMEOSTASIS

The primary function of the kidney is homeostasis. Homeostasis is the maintenance of internal environment from the harms of fluctuations in the external environment. Kidney accomplished this by the formation of urine, kidneys regulate various activities in the body, which are concerned with homeostasis such as.

• Excretion of waste products. Kidneys excrete the unwanted waste products, which are formed during metabolic activities:

1. Urea (cease manufactured form of amino acid metabolism)
2. Uric acid (cease manufactured form  of nucleic acid metabolism)
3. Creatinin (cease manufactured form  of metabolism in muscles)
4. Bilirubin (cease manufactured form of hemoglobin degradation)

Kidneys additionally excrete harmful overseas chemical materials which include toxins, drugs, heavy metals, pesticides and many others.

• Maintenance of Electrolyte Balance. Preservation of electrolyte balance, mainly sodium is in relation to water balance. Kidneys reserve sodium if the osmolarity of body water decreases and do away with sodium when osmolarity increases. It does this via lively shipping of sodium from the proximal tubule of the nephron.
• Preservation of Water Balance. Kidneys hold the water stability in the body via conserving water, whilst it is reduced and excreting water while it is far in extra in the body. This is a crucial process for homeostasis in the body.
• Maintenance of Acid-Base Balance. The pH of blood and body fluids must be maintained within a narrow variety for a healthful dwelling. It is achieved with the aid of the characteristic of kidneys. A pair of the kidneys prevents the body from developing acidosis via disposing of certain metabolic acids like sulphuric acid and phosphoric acid.

REGULATION OF BLOOD CALCIUM LEVEL

Kidneys play a position inside the regulation of blood calcium degree via activating 1,25-dihydroxycholecalciferol into vitamin D. Vitamin D is essential for the absorption of calcium from the intestine.

HEMATOPOIETIC FUNCTIONS

Kidneys stimulate the production of the erythrocytes by secreting erythropoietin. Erythropoietin is the important stimulating factor for erythropoiesis. Kidney also secrets another factor called thrombopoietin, which stimulates the production of thrombocytes.

REGULATION OF BLOOD PRESSURE

Kidneys play an important role in long-term regulation of arterial blood pressure by two ways:

1. With the aid of regulating the quantity of extracellular fluid.
2. Through renin-angiotensin mechanism. 

Renin-angiotensin system

Renin is secreted by the juxtaglomerular apparatus of the nephron. when released into the blood it acts on the plasma protein called angiotensinogen or renin substrate. By a series of complex reactions, it converts renin substrate into the angiotensin 2. The actions of angiotensin 2 in maintaining blood pressure are:

1. On Blood Vessels:

It increases atrial blood pressure by directly acting on the blood vessels and causing vasoconstriction. It does this also indirectly by increasing the release of noradrenaline from postganglionic sympathetic fibers.

2. On Adrenal Cortex:

It stimulates adrenal cortex to secrete aldosterone. It acts on renal tubules and increases retention of sodium, which is also responsible for the elevation of blood pressure.

3. On Kidneys:

It constricts the efferent arteriole of the glomerulus to regulate glomerular filtration rate, which causes a decrease in filtration after an initial increase.

ENDOCRINE FUNCTIONS

 Kidneys secrete many hormonal substances in addition to erythropoietin and thrombopoietin. Some of the main hormones are listed below:

1. Renin
2. Prostaglandins
3. Erythropoietin
4. 1,25-dihydroxycholecalcifeferol
5. Thrombopoietin

Congestive Heart Failure

Congestive heart disease is a clinical condition which results from deficient cardiac stroke volume, relative to body need, with the inability of the cardiac output to keep pace with the venous return i-e, the heart is unable to pump all the blood coming to it. Heart failure does not mean the heart has stopped working. Rather, it means that the heart's pumping power is weaker than normal. About 670,000 people are diagnosed with heart failure each year. It is the leading cause of hospitalization in people older than age 65.

Etiology

Left Ventricular Failure

Volume overload

• Aortic regurgitation
• Mitral regurgitation
• Patent ductus arteriosus

Pressure overload

• Systemic hypertension
• Aortic stenosis

Myocardial diseases

• Ischemic heart disease
• Dilated cardiomyopathy
• Cardiomyopathy coronary artery disease

Right Ventricular Failure

Volume overload

• Atrial septal defect
• Tricuspid regurgitation

Pressure overload

• Pulmonary hypertension
• Pulmonary stenosis

Myocardial disease

• Cardiomyopathy (dysfunction of left and right ventricles)

Causes of Heart Failure

•  Coronary heart disease. A disease of the arteries that supply blood and oxygen to the heart, causes decreased blood flow to the heart muscle. If the arteries emerge as blocked or critically narrowed, the heart turns into starved for oxygen and vitamins.
• Cardiomyopathy. Damage to the heart muscle from causes other than artery or blood flow problem, such as from infections or alcohol or drug abuse.
• Decreased cardiac output ( Forward failure ). Decreased cardiac output due to decreased heart function results in diminished filling of the arterial tree. Therefore blood supply of the organs is reduced which may lead to ischemia.
• Damming of blood ( backward failure ). Heart fails to pump the whole blood coming to it resulting in blood damming back into the venous system. Accumulation of deoxygenated blood in the tissue venous system may produce disturbed organ function.
• Other conditions. Conditions including high blood pressure, valve disease, thyroid ailment, kidney ailment, diabetes, or coronary heart defects present at birth can all reason coronary heart failure. In addition, heart failure can occur when several disease or conditions are present at once.

Signs and Symptoms of Heart Failure

The symptoms can include:

• Congested lungs. Fluids amassed in the lungs can purpose shortness of breath with a workout or difficulty breathing at rest or whilst mendacity flat in bed. Lung congestion can also purpose a dry, hacking cough or wheeze.
• Dyspnea. A sense of breathlessness, initially on exertion than on rest also. The dyspnea is maximal when congestion of lung is greatest as in exercise.
• Orthopnea. Dyspnea on lying flat is called orthopnea. It results from increased amount of venous return to thorax from lower extremities when the patient is in lying position. 
• Paroxysmal nocturnal dyspnea. Dyspnea during sleep which awakens the patient with severe breathlessness, accompanied by a choking sensation and coughing is called paroxysmal nocturnal dyspnea.  

Signs

• Tachycardia. cardiomegaly, third heart sound, and fine crepts at the lung bases. 
• Chronic dilation of the left atrium may also occur which may be associated with atrial fibrillation.   

Types of Heart Failure

The coronary heart failure may be categorized in several approaches.

1. Chronic heart failure versus Acute heart failure 
2.  Biventricular failure, left as opposed to right ventricular failure
3. Forward as opposed to backward failure
4. Systolic as opposed to diastolic failure
5. Low output versus excessive output failure  

Investigations

ECG
ECG may show:

• Right or left ventricular hypertrophy
• Myocardial ischemia or infarction
• Arrhythmia

Echocardiography
Echocardiography is a very important tool for the diagnosis and cause of heart failure, it may demonstrate:

• Systolic or diastolic ailment of left or right ventricle
• Valve disease
• Local wall motion abnormalities in ischemic heart disease
• Cardiomyopathy
• Ejection fraction
• Intracardiac thrombus 

X-Ray Chest

It may show:

• Hilar congestion
• Cardiomegaly
• Evidence of pulmonary hypertension
• Pleural effusion

  

Stomach and its Structure

The stomach is a muscular, hollow pouch like structure situated on the left side of the abdomen, thus helping in the digestion of the food. It is present nearly in every animal which chews food. In humans, it is located between the esophagus and the small intestine, from esophagus it enters stomach through a narrow section called esophageal sphincter. On the entrance of the food, it releases a large number of enzymes which combines with food, making chyme, thus helping in the digestion, usually 2nd step of digestion occurs here and useful contents get absorb into the blood for further processing. In adults, it has a capacity to store about 1500ml of the chyme.
The stomach is relatively fixed at both ends but very mobile in between. It tends to be high and transversely arranged in the short, obese person ( steer-horn ) and elongated vertically in tall, thin person ( J-shaped stomach ). Its shape undergoes considerable variation in the same person and depends on the volume of contents, the position of the body and the phase of respiration.

Structure of the Stomach

In humans, the stomach is divided into following parts:

Fundus: It is a dome-shaped structure, located left side of the cardiac orifice projecting upward and full of gas.

Body: It extends from the cardiac orifice to the incisura angularis, a constant notch in the lesser curvature of the stomach.

Pyloric antrum: This extends from the incisura angularis to the pylorus. 

Pylorus: This is the tubular structure of the stomach. The thick muscular wall is called the pyloric sphincter, and the cavity of the pylorus is called pyloric canal. 

Openings: The stomach has two openings the cardiac orifice and the pyloric orifice. The cardiac orifice is the region where the esophagus enters the stomach, that prevents the regurgitation of the stomach contents into the esophagus. The pyloric orifice is formed by the pyloric canal, which is about a 2.5cm long tube. The pylorus is located in the transpyloric plane, which can be recognized by the presence of the slight constriction on the surface of the stomach.

Lesser and greater Curvature: It extends from the cardiac orifice to the pylorus, forming right border of the stomach, which is suspended from the liver by the lesser omentum, The greater curvature is longer than the lesser curvature, which extends from the left of the cardiac orifice, over the dome of the fundus, and along the left border of the stomach to the pylorus.

Function

In addition to the secretion of the enzymes, it performs following functions too:

1. It stores meals (within the grown up it has an ability of approximately 1500ml ).
2. It mixes the meals with gastric secretions to shape semi-fluid chyme.
3. It controls the rate of transport of the chyme to the small gut in order that efficient digestion and absorption can take place.

Layers of the Stomach 

As we discussed earlier that the human stomach is hollow, muscular organ, which is consist of the layers packed on each other, providing strength to the stomach. It is consist of the following layers:

• Mucosa

This is the innermost structure of the stomach and has three layers the mucosal epithelium, the lamina propria, and the muscularis mucosa, collectively called lumen of the stomach.

• Submucosa

This surrounds the mucosa and contains loose connective tissue, blood vessels, and the nerves.

• Muscularis Externa

It consists of the connective tissues whose fibers move in a different direction from each other to strengthen the stomach, which is as follow, the oblique, circular and the longitudinal muscle.

• Serosa

It lies next to the muscularis externa and includes a dense network of the blood vessels.

Anatomical Relation

Anteriorly: Anterior to the stomach, the anterior abdominal wall, the left costal margin, the left pleura and lung, the diaphragm, and the left lobe of the liver are located.

Posteriorly: The lesser sac, the diaphragm, the spleen, the left suprarenal gland, the superior part od the kidney, the splenic artery, the pancreas, the transverses mese-colon, and the transverses colon.

Blood Supply

• Arteries

The arteries are derived from the celiac artery and supply blood to the stomach.

The left gastric artery: It supplies the lower third of the esophagus and the upper right part of the stomach.

The right gastric artery: It supplies the lower right part of the stomach.

The short gastric artery: It supplies blood to the fundus of the stomach.

The left gastroepiploic artery: It supplies blood to an upper part of the greater curvature.

The right gastroepiploic artery: It supplies blood to the lower part of the greater curvature of the stomach.

• Veins

The veins drain into the portal circulate, The left and right gastric veins drain at once into the portal vein. The short gastric veins and the left gastroepiploic veins be a part of the splenic vein. The right gastroepiploic artery then joins the superior mesenteric vein. 

    

The Inguinal Canal

The inguinal canal is the tubular structure that is located in the inguinal region, the lower portion of the anterior abdominal wall, with the pubic tubercle medially, the thigh inferiorly, and the anterior superior iliac spine superolaterally. It is about the 4cm long tube in the adult and extends from the deep inguinal ring to the superficial inguinal ring, which is a hole in the fascia transversalis downward to the superficial inguinal ring, a hole in the aponeurosis of the external oblique.

It lies immediately above and parallels to the inguinal ligament. In the newborn child's the deep inguinal ring lies posterior to the superficial ring but later it comes to the lateral side due to the growth. The inguinal canal is made up of:

1. Superficial and deep rings ( openings )
2. Anterior and superior walls
3. Floor and Roof ( inferior and superior walls )

• Deep Inguinal Ring: The deep inguinal ring is an oval opening that is present in the fascia transversalis, it lies about 1.3cm above inguinal ligament midway between the anterior superior iliac spine and the symphysis pubis. The inferior epigastric vessels are present medial to it, which pass upward from the external iliac vessels. The margins of the deep inguinal ring give attachment to the internal covering of the spermatic fascia.

• Superficial Ring: The superficial ring is a triangular shaped ring situated in the aponeurosis of the external oblique muscle that lies immediately above and medial to the pubic tubercle. The margins of the external oblique are called crura, which give attachment to the external covering of the spermatic cord.

Walls of the Inguinal Canal

• Anterior Wall: The anterior wall of the inguinal canal is formed by the aponeurosis of the external oblique muscle, which is reinforced laterally with the aid of the internal muscle. It lies opposite to the weakest part of the posterior wall, specifically, the deep inguinal ring.
• Posterior Wall:  It is formed by the conjoint tendon, and strengthen by the fascia transversalis laterally.
• Superior Wall:  Also known as the roof of the inguinal canal, it is formed by the transversalis fascia, internal oblique, and the transversus abdominis.
• Inferior Wall:    Also called floor of the inguinal canal, it is formed by the inguinal ligament and thickened by the lacunar ligament.

Functions of the Inguinal Canal

The inguinal canal permits structures of the spermatic cord to bypass to and away from the testes to the abdomen in the males, at the same time as in the females it acts as a passageway to pass the round ligament of the uterus from the uterus to the labium majus.

Nerve Supply

The inguinal canal is innervated by the ilioinguinal nerve a branch of the first lumbar nerve (L1). Note that the ilioinguinal nerve does no longer pass via the deep inguinal ring, and therefore it only travels through a part of the inguinal canal. 

 

 

Muscles of the Abdominal Wall

The abdomen is the region of trunk situated between diaphragm below and the inlet of the pelvis below. It accommodates a large number of organs and its muscles strengthen or give proper shape to the human skeleton.
From exterior to interior the muscles of the anterior abdominal wall are the external oblique, internal oblique, and transversus abdominis, which are aponeurotic in front. In addition to these, it also contains a wide vertical thin sheet called rectus abdominis, which is separated from its compartments by means of linea alba. The posterior abdominal wall consists of psoas major, quadratus lumborum and iliacus muscle.

Anterior Abdominal Wall

As we discuss earlier the anterior abdominal wall consist of the external oblique, internal oblique, and the transversus abdominis. Their details are as follow:

• External Oblique

It's miles a skinny, wide muscular sheet, arise from the outer surfaces of the lower eight ribs, which fans ahead laterally to be inserted into the xiphoid process,  pubic crest (bone), pubic tubercle (bone), linea alba and anterior half of the iliac crest. The aponeurosis of the external oblique incorporates superficial inguinal ring and additionally forms the inguinal ligament, pectineal ligament and the lacunar ligament (connects inguinal ligament to the pectineal ligament).

Nerve supply: It is innervated by lower six thoracic and lumbar nerves.

Action: It compresses abdominal contents and helps in micturition, defecation, and parturition.

• Internal Oblique

It is also a thin muscular sheet, which lies deep to the external oblique, its fibers fan perpendicular to that of external oblique. Internal oblique arises from the lumbar fascia, anterior two third of the iliac crest, lateral two third of the inguinal ligament. They move upward and forward to be inserted into the lower borders of the lower three ribs and their intercostal cartilages, xiphoid process, linea alba and pubic symphysis.

Nerve supply: It is innervated by lower six thoracic and lumbar vertebrae.

Action: Similar as external oblique.

• Transversus Abdominis

It is the deepest muscle among all, which arise from the costal cartilages of the lower six ribs, lumbar fascia, iliac crest and lateral two third of the inguinal ligament, which is inserted into the xiphoid process, linea alba, and pubic symphysis. Its fibers move forward horizontally and contain the deep inguinal ring.

Nerve supply: Lower six thoracic and lumbar nerves.

Action: Similar as external and internal oblique.

• Rectus Abdominis

The rectus abdominis is long strap muscle that arises from the front of the pubic crest and pubic symphysis. It is inserted into the fifth, sixth, and seventh costal cartilages and the xiphoid process. It is divided into three distinct segments by three transverse tendinous intersections: one at the level of xiphoid process, one at the level of the umbilicus and another halfway between these two. These intersections are strongly attached to the anterior wall of the rectus sheath.

Nerve supply: It is innervated by lower six thoracic nerves.

Action: It pulls the ribs and the pelvis in and curves back.

Posterior Abdominal Wall

The posterior abdominal wall consist of following muscles:

• Psoas Major

The psoas major arises from the transverse processes, bodies, and intervertebral discs of 12th thoracic to 5th lumbar vertebrae. Its fibers move downward laterally to be inserted into the lesser trochanter of the femur, It is enclosed in a fibrous sheath that is derived from the lumbar fascia, it forms medial arcuate ligament superiorly.

Nerve supply: It is innervated by the lumbar plexus.

Action: It flexes the thigh on the trunk and if thigh is fixed flexes trunk on the thigh.

• Quadratus lumborum

  It is quadrilateral shaped, flat muscle that lies obliquely with vertebral column. It arises from the iliolumbar ligament, which is the adjoining part of the iliac crest and the transverse process of the lower lumbar vertebrae. It moves upward medially to be embedded into the 12th rib and upper four lumbar vertebrae.

Nerve supply:  It is innervated by the lumbar plexus.

Action: It boosts or recessed the 12th rib for the duration of respiration and laterally flexes the vertebral column to the same side.

• Iliacus 

It is fan-shaped muscle which arises from the upper surface of the iliac fossa. The fibers of iliac fossa join the lateral side of the psoas tendon to be inserted into the lesser trochanter of the femur, which is commonly called iliopsoas muscles.

Nerve supply: This muscle is supplied by femoral nerve, a branch of the lumbar nerve.

Action: It flexes the thigh on the trunk at the hip joint and if thigh is fixed then flexes trunk on the thigh.

 

      

Necrosis and its Types

Necrosis is the type of cell injury, which results in premature death of cells in living tissue, in response to non-stop physiological stress by means of autolysis. It is far an unprogrammed cell loss of life and may be due to factors external to the cell or tissue, together with infection, toxins, or trauma which bring about the unregulated digestion of cell components.

Types of Necrosis

There are six types of necrosis:

• Coagulative Necrosis

It is an accidental cell death typically caused by ischemia or infarction, which is characterized by the formation of a gelatinous substance in dead tissue and can be observed by light microscope. During coagulation protein ( albumin ) transform into a firm and opaque state, which can be seen in hypoxic conditions. It occurs primarily in tissues such as kidney, adrenal glands, and heart. 

• Liquefactive Necrosis

It is a type of necrosis, during which the affected cell is completely digested by hydrolytic enzymes, resulting in soft, circumscribed lesion consisting of pus and fluid remains of necrotic tissue. The necrotic fluid is creamy yellowish in appearance, due to the presence of dead leukocytes and commonly known as pus.

• Gangrenous Necrosis

It is a not communicable disease, caused by a critically an insufficient blood supply.  Smoking and diabetes may increase the risk of gangrenous necrosis. Types of gangrene necrosis may differ in symptoms which include

1. Dry gangrene
2. Wet gangrene
3. Gas gangrene
4. Internal gangrene

• Caseous Necrosis

It can be considered a combination of a coagulative and liquefactive necrosis. Typically caused by bacteria, fungi, and some foreign substances. During caseous necrosis, dead cells disintegrate but not completely digested, and a tissue maintains a cheese- like an appearance. 

• Fat Necrosis

It is a benign condition which is characterized by action upon fat by fat digesting enzymes. During which lipases splits fat into glycerol and fatty acids. Which then combines with alkali metals to form soap, called saponification, which can cause critical conditions.

• Fibrinoid Necrosis

It is miles a form of necrosis, which is resulting from immune-mediated vascular damage. It's far marked by means of complexes of antigens and antibodies, on occasion known as ''immune complexes'' deposited inside arterial walls together with fibrin.

Cellular Changes during Necrosis

The cellular changes can be classified into following stages.

• Karyolysis

During which nucleus fades due to loss of DNA by degradation.

• Pyknosis

The nucleus shrinks and chromatin condensed.

• Karyorrhexis

The shrunken nucleus fragments to finish dispersal. 

The Pleura

The pleura is a thin membrane of connective tissue, lie on the either side of the mediastinum within the chest cavity. Each pleura has two layers parietal pleura and the cervical pleura.

Parietal pleura

The parietal pleura, which lines the thoracic wall, covers the thoracic layer of the diaphragm, and the lateral aspect of the mediastinum, and extends into the root of the neck to line the undersurface of the supra-pleural membrane at the thoracic outlet. 

Cervical pleura

The cervical layer of the mediastinum covers outer surfaces of the lungs and extends deep into the depths of the interlobar fissures.

The two layers of the pleura become continuous with each other forming cuff of the pleura, near to the hilum of the lung. The cuff of pleura hangs down to allow movement of the blood vessels and bronchi during respiration, this structure is referred to as pulmonary ligament.

Between these two layers, a small space is situated called pleural cavity. To avoid confusion with thorax cavity it is referred to as pleural space. Pleural space contains a fluid, usually 5 to 10ml in normal conditions. It acts as the lubricant between two layers. 

Nerve supply of the pleura

The pleura is innervated by both sensory nerves and autonomic nerves, depending on the surface which it covers.

The parietal pleura is sensitive to pain, temperature, touch and pressure and is supplied as follow:

The mediastinal pleura is supplied by the phrenic nerves.

The costal pleura is segmentally supplied with intercostal nerves.

The mediastinal pleura is supplied over the domes by the phrenic nerves and around the periphery by lower six intercostal nerves.

The cervical pleura is insensitive to the pain, touch, and pressure but is sensitive to the stretch. It receives autonomic nerve supply from the pulmonary plexus.

Pleural effusion

It is a condition during which the fluid in the pleural cavity increases abnormally due to any inflammation and malignancy or impairs the drainage of the fluid, resulting in decreased lung expansion, sound and dullness on percussion over the effusion. 

The presence of 300ml of fluid in the costodiaphragmatic recess in an adult is sufficient to enable its clinical detection.

Pleurisy

Inflammation of the pleura secondary to the inflammation of the lung results in the pleural surface becoming coated with inflammatory exudate, causing the surfaces to be roughened. This roughening produce friction, resulting in severe pain, this medical condition is referred to as pleurisy.    

Thoracic Cavity and its Structure

The thoracic cavity is the region between the root of neck and diaphragm, which separate it from the abdominal cavity. It is also known as chest cavity and thorax. It contains large nimber of body organs and its associated structures, which leads into the cavity through the oblique opening, situated anterior to the body of 1st thoracic vertebra and leaves by a large opening, which is situated inferior to the xiphoid process and anterior to the body of the 12th thoracic vertebra.

The Structure of Thoracic Wall

 Wall of the thoracic cavity, externally covered with skin and muscles which connect shoulder girdle to the trunk. The thoracic wall is formed posteriorly by the thoracic part of the vertebral column, anteriorly by the sternum and costal cartilages, laterally by the ribs and intercostal spaces, superiorly by the supra-pleural membrane and inferiorly by the diaphragm, which separates it from the abdominal cavity. In addition to these following are some of the main structures of the rib cage.

Sternum

It is a flat bone, situated in the midline of the anterior chest wall. In addition to supporting rib cage, it has a dominant role in the formation of red blood cells ( hematopoiesis ). Sternum has three main structures, which are given below.

• Manubrium

It is the superior structure of the sternum, which articulate with the body of sternum and forms manubriosternal joint with it, which lies anterior to the body of the 3rd thoracic vertebra. Manubrium provides a site for articulation to the clavicles, first rib and an upper portion of the 2nd rib.

• Body of the sternum

The body of the sternum articulates above with manubrium and below with xiphoid process, giving rise to the xiphisternal joint. It also provides a site for articulation to the ribs ranging from 2nd to 7th.

• Xiphoid Process

It is the inferior structure of the sternum, it articulates above with the body of sternum and forms xiphisternal joint ( cartilaginous joint ), which lies anterior to the body of the 12th thoracic vertebra.

Ribs

 In humans, chest cavity has 12 pairs of ribs, which articulates anteriorly with the lateral body of the sternum and posteriorly with the numerically corresponding vertebra of the thoracic part of the vertebral column. Ribs are of three types, true ribs, false ribs and floating ribs.

Sternum and Bone marrow Biopsy

Sternum provides support and protection to the internal organs, situated in the chest cavity. Since it contains red hemopoietic marrow throughout life, it is the common site for marrow biopsy. During red bone marrow biopsy, a wide, bore needle is introduced into the cavity through the anterior surface of the bone.

Thoracic Outlet

In humans, chest cavity communicates with the root of the neck through a small opening called thoracic outlet. This is the region through which most parts of the body organs and the other structures ( blood vessels and nerves ) leads to or away from thorax cavity, therefore it's named as an outlet. 

The upper opening is bounded posteriorly by the first thoracic vertebra, laterally by the medial parts of the first ribs and their costal cartilages. It is an anteriorly bounded with superior part of the sternum (manubrium). The opening is obliquely placed forward and upward. Because of the obliquity of the opening, the apices of the lung and pleurae project upward into the neck.

It communicates with the abdomen through the large opening, which is posteriorly bounded with the 12th thoracic vertebra, laterally by curving costal margins, and anteriorly by the xiphisternal joint.

Sternal angle

It is also known as the angle of Louis. Sternal angle is formed by the articulation between the manubrium and the body of the sternum. It lies at a level to the 2nd costal cartilage and anterior to the midsection between 3rd and 4th vertebra of the thoracic vertebral column. It is recognized by the presence of transverse ridge on the anterior surface of the sternum,        

         

   

How To Increase Bone Density Fast

Like liver and some other parts of your body, your bones are always in a state of flux, replacing old bone cells with new once. This process lasts for whole life, but that process does not stay in perfect balance if the conditions are not right and without your help. According to the research, the amount of bone turnover in the people's older than 50 is high than as compared to the amount of new bone production. Which results in the bone weakening, putting you at greater risk for fractures. In both males and females bone density peak at about age of 30, and it's all downhill from there.
As we know that time is not our friend when it comes to health and money. But no matter what your age, you can improve your bone health by changing some of your daily routines. There are a lot of strategies you could employ that work. They work whether you have already been diagnosed with osteoporosis or you have seen it run in your family and simply want to prevent the conditions from forming later on in life. So, these are some of the vital and workable tips to obtain hard and denser bones fast.

• Taking plenty of calcium

Our bones and teeth contain about 99% of calcium. Which shows that it plays a vital role in bone strengthing. Apart from this its concentration also regulates the hormonal secretion. Getting sufficient calcium will help you grow healthy bones and maintain bone density. We can get sufficient calcium from dairy products, such as milk, cheese, and yogurt. Vegetable sources rich in calcium include turnips and colored greens, Chinese cabbage, and broccoli. 

• Consuming plenty of vitamin D

Vitamin D helps our body to absorb calcium from the blood. It also plays a crucial role in bone rebuilding. Vitamin D is not present in most foods. Fatty fish, such as swordfish, tuna and salmon are best sources of vitamin D. Spending time the sunshine is another best way to get sufficient vitamin D. Beef liver, some mushrooms, and egg yolks contain a small amount of vitamin D.

• Stay away from caffeine and salt

Caffeine causes your body to excrete calcium more rapidly. So drink less regular coffee, tea, and caffeinated soft drinks. Like alcohol and caffeine, salty foods can cause you to lose calcium and can speed bone loss. Processed and canned foods tend to be high in salt, so limit your intake. 

• Medications

There are several medications available to increase bone density. Bisphosphonates are the common class of drugs used for that purpose. These include risedronate and alendronate. They did this by preventing normal resorption of special kind of bone cells called osteoclasts. According to research, on an endocrine web, calcitonin drugs also work by inhibiting the activity of osteoclasts and therefore resorption. Estrogen replacement therapy is also helpful in improving bone density.

• Keep your weight and insulin in check

If you are prone to osteoporosis, you may be shocked to discover that all the calcium in the world is not going to help you maintain your bones if your insulin level is high. In fact, most of that calcium will be eliminated through your urine, or even worse, from calcification in your arteries.
Recent research also revealed that one of the body's obesity-related hormone, insulin, is linked to osteoporosis, an increased risk of fractures, and reduced muscle strength and mass. Insulin signals secretion of a hormone that promotes glucose metabolism which increases chances of bone breaking.

Natural ways to control osteoporosis

Recent research on osteoporosis revealed that taking a diet enriched in vitamin D and calcium can reduce the symptoms of osteoporosis. Following are some of the surprising foods that keep bones strong and prevent osteoporosis.

• Grapefruit
• Olive oil
• Sardines
• Walnuts and Flaxseed oil

     

     

   

  

How To Know If a Person loves You

Nonverbal communication comprises much of our everyday interactions, so it is no wonder that lots of questions about meaning arise when it comes to our partners. The most confusing question that comes to mind: Do they love me? To find out if someone loves you can be tricky and difficult. If they have not said as much yet. If they said so, some people do not trust just the words until they figure out proof of love. If someone loves you or he/she is extremely interested in you then most probably he/she won't tell you directly until he/she becomes sure of your emotions towards him/her.
  If you would like to know if the person you love truly loves you back, then you have to pay attention to how the person acts, what they say, and what they do when you are together. In a real sense, this is a terrible idea. Do not do that. Instead, focus on your time with your partner and be present and in the moment. If you need more clues, to know whether someone loves you or not, you just need to open your eyes for following signs. If you saw many of them then make sure that the person likes you. Keep in mind that the presence of only one signal is not enough to determine whether someone loves you or not, and so you should look for more than one sign to conclude whether he/she truly loves you.

Signs that show that someone loves you

• How he/she act around you

Part of being love means being completely open to the other person. See if the person can act naturally around you, then that may be love. For instance, if your partner shares her/his deepest emotions with you and is comfortable with it, then that is love.

• The way he/she look at you

Actions can speak louder than words. Eye contact is the best way to deliver love message to your crush. A lot can be said in the eyes. does their eye look kind and sweet? Do you ever catch them looking at you when you are doing something else? These all are pretty ways of communicating love. 

• How he/she treat you

If his or her respect for you is inconsistent or only occurs sometimes, your relationship can't flourish.

In love, you can not pick and choose the place and time to kind, respectful, and considerate. Observe his behaviour, does he talk to you with affection, care, and respect? Your partner either is all of these things or he is not. It is really that simple.

• Smiles and phone calls

Observe her or his smile. A smile will not fade away quickly if the person was genuinely interested in you. Only fake smiles fade away quickly while true smiles stay a little longer before they disappear. If someone likes you then you will find him or her calling for trivial reasons. When the frequency of these calls increases then this usually indicates that there is something behind it.

• Notice what the person says

True commitment means seeing a forever with another person. If the person talks about the future and always includes you in it, then there is a good chance he loves you. And if he/she talks about what your kids will look like, then he/she may really love you. Signs of compromise and selflessness are also huge indicators that he/she is in love with you. 

          

How To Celebrate Holidays Alone

The holidays seem to have a special way of making you feel like crap if you are alone. Maybe you are nursing a recent breakup. Maybe you just started college and can not afford to fly back home. Whatever the scenario, if you are spending the holidays by yourself and it is getting you down, then you must know how to cope. Being alone for holidays does not have to mean being lonely. It can be relaxing and enjoyable. You can use your holiday to do all the things you never have time for in your everyday routine. Spending time alone is a way to recharge your mental batteries and regroup-everybody needs to do it. So get over your fear of missing out or your reservations about being seen somewhere solo, and embark on a mission to treat yourself with some awesome dates. Fill your time with activities you enjoy, as well as few things that benefit others, to make the season feel special and potentially even rewarding.

• Go out and do something new

Do not feel like you have to stay in your house because you are spending your holiday alone. If you do not want to a lot of money, take your time visiting stores, and treat yourself to something small that you have been wanting. Use your holidays as an opportunity to try something new like swing dances, swimming, and painting.

• Travel somewhere new

The holidays are supposed to be a happy time, so focus on what you can do to be happy now. In short: include yourself  a little. If you can afford it, that might mean taking a trip, even if it is just a short weekend trip to a nearby town. When you travel with other people, you always end up making compromises on what sites to see, and what activities to do. Travelling alone gives you the luxury of going at your own place.

• Focus on what makes you happy

Perhaps the most important tip of all: instead of focusing on what you do not have, and thinking about what makes you sad and depressed..... focus on what you love. What makes you happy? If you focus on that, that will be the reality.

• Think yourself as a free bird

Do not beat yourself up over feeling empty instead of full of the joy of the present moment. You are feeling empty because that is a part of the illness. It is not your fault, and you are not a bad person or a loser because of it. Always try to stay away from the alcohol. It may relieve the pain for a little while but you will probably end up feeling sad and maudlin.

• Express your creative side

Explore several of your creative pursuits as a way to turn the focus away from typical holiday activities. Paint a picture, get experimental in the kitchen. If you try out new recipes on your own and mess up the only hunger, a disappointed person you have to deal with it yourself. You can work on perfecting the dish until it is just right then serve up a flawless result the next time you are with friends, and act like it was your first try.        

    

How To Predict Boiling Points and Solubilities of Commpounds

Boiling Points

The boiling point of a substance is the temperature at which the vapour pressure of the liquid equals the pressure surrounding liquid and liquid changes into vapour. The boiling point of a liquid depends upon the bonding present in it, but it varies, as well as changed in surrounding environmental pressure. 

In general, compounds with ionic bonds have high normal boiling points, if they do not decompose before reaching such high temperature. Many metals have high boiling points, but not all. Very generally - with other factors being equal - in compounds with covalently bonded molecules, as the size of the molecule increases, the normal boiling point increases. Another factor that affects the normal boiling point of a compound is the polarity of its molecules. As the polarity of a compound's molecules increases, its normal boiling point increases, other factors being equal. In addition to these boiling points and vapour pressures of substance can be also affected by the presence of dissolved impurities ( solutes ) or other miscible compounds. The degree of effect depends on the concentration of impurities or other compounds. This effect is called boiling point elevation. For instance, salt water boils at a high temperature than pure water.

Solubility

Solubility is a chemical property of a substance called solute to dissolve in a solid, liquid, or gaseous solvent. Solubility, fundamentally depends on the physical and chemical properties of the solute or solvent as well as on temperature, pressure, and the pH of the solution. Solubility may also strongly depend on the presence of other species dissolved in the solvent, for example complex-forming anions ( ligands ) in liquids. All chemical substance are classified into miscible, immiscible, and partially miscible compounds, depending on their ability to get dissolve in a solvent molecule. The extent of solubility ranges widely, from infinitely soluble such as ethanol in water, to poorly soluble, such as silver chloride in water. The smaller particle is, the faster it dissolves in solvent. The solubility of a given solute in a given solvent may increase or decrease with increase in temperature depending on the nature of solute. For many solids dissolved in liquid water, the solubility increases with increase in temperature, while the solubility of ionic solutes tends to decrease due to the change of properties and structure of liquid water 

Predicting Trends in Boiling Points and Solubilities

Remember the following points when predicting trends in boiling points and water - solubilities of compounds:

• When considering boiling points of different types of organic compounds, first consider the type of intermolecular forces present in the molecule. For boiling points, the order is :

Ionic Compounds   >   Hydrogen Bonders   >   Dipole Dipole   >   Induced Dipole

Branching, etc, need not be considered. The non polar compound will have the lowest boiling point,

• In the absence of hydrogen bonding, boiling points increase with molecular weight. The higher the molecular weight, the higher is the boiling point.
• For compounds of similar molecular weights, boiling points increase with the degree of hydrogen bonding. The greater the degree of hydrogen bonding, the higher will be the boiling point.
• For alcohols of same molecular weights, branched-chain alcohols will have lower boiling points. This is because the decreased surface area leads to decreased Van der waals force.
• For alcohols of different molecular weight, the straight-chain alcohol containing the greater number of carbon atoms will have higher boiling point. This is because of increased van der waals force.
• Compounds capable of forming hydrogen bonds with water will be soluble in water.
• Degree of hydrogen bonding, chain-length ( molecular weight ), and branching will determine the extent of solubility.
• Compounds with shorter non-polar chain are most soluble in water.
• Among alcohols, the solubility in water depends mainly on the number of -OH groups. Greater the number of -OH groups, greater will be the solubility. 

    

How To Predict Acidities and Basicities of Compounds

Acidity
An acid is a molecule or ion capable of donating a hydrogen ( proton or hydrogen ion ), or, alternatively, capable of forming a covalent bond with an electron pair. This property of a molecule to donate proton is referred to as its acidity.
PREDICTING TRENDS IN ACIDITIES
Remember the following points when predicting acidities of compounds:

• Acids donate a proton. That is, they lose a proton.
• Acidity ( acid - strength ) depends on the ease with which they lose a proton.
• Aliphatic carboxylic acids are acidic and lose a proton readily. This is because the carboxylate ion formed by ionization or reaction with a base is stabilized by resonance.
• The acidity of substituted aliphatic carboxylic acids depends on the inductive effect and position of the substituents. Electron - releasing alkyl groups decreases the acidity. Electron - withdrawing substituents ( F, Cl, CN, COOH ) increases the acidity.
• Phenol is acidic. This is because the phenoxide ion formed by ionization or reaction with a base is stabilized by resonance.
• The acidity of phenols depends on the nature and position of the substituent. Electron - releasing alkyl groups decrease the acidity of phenols. Electron - withdrawing substituents ( Cl, CN ) increases the acidity of phenols.
• Phenols are much more acidic than alcohols. This is because alcohols give alkoxide ions on the loss of a proton. The alkoxide ions so formed are not resonance stabilized.
• p-Nitrophenol is almost 1000 times more acidic than phenol.
• Picric acid ( 2,4,6-Trinitrophenol ) is as strong as HCl.
• Alcohols are weaker acids than water.
• Thiols are more acidic than alcohols.
• Aromatic carboxylic acids are acidic and lose a proton readily. This is because the carboxylate ion formed by ionization or reaction with a base is stabilized by resonance.
• The acidity of substituted benzoic acids depends on the nature and position of the substituent. Electron - releasing substituents ( CH3, OCH3 ) decreases the acidity of a benzoic acid. Electron - withdrawing substituents increase the acidity of a benzoic acid.
• Almost all ortho substituents increase the acidity of a benzoic acid.
• The acidity of a compound may be expressed quantitatively in terms of its acidity constant, pKa. Stronger acids will have smaller pKa. Weaker acids will have larger pKa.

      Basicity

The ability of a chemical species to accept or attract proton is referred to as its basicity. Basicity of a molecule is normally expressed by the acidity of the conjugated acid ( conjugate acid - base pair ).

PREDICTING TRENDS IN BASICITIES

Remember the following points when predicting basicities of compounds:

• Amines are basic because they have a lone pair ( unshared pair ) of electrons on nitrogen. This lone pair of electrons is available for formation of a new bond with a proton or Lewis acids.
• Basicity ( base - strength ) depends on the degree of availability of the lone pair of electrons.
• Any factor which increases the availability of the lone pair of electrons on nitrogen for protonation, increase the basicity.
• Electron - releasing groups on the nitrogen atom of amines increase the basicity an electron - withdrawing groups decrease the basicity.
• Aliphatic amines are stronger bases than ammonia.
• Aromatic amines are less basic than aliphatic amines. This is because the lone pair of electrons on the nitrogen in aromatic amines is less available due to delocalization. 
• Electron - releasing groups increase the basicity of aromatic amines. Electron - withdrawing groups on the aromatic ring decrease the basicity.
• The basicity of a compound may be expressed quantitatively in terms of its basicity constant, pKb. Stronger bases will have larger pKb. Weaker bases will have smaller pKb.

How To Manufacture Synthetic Petrol

Fortunately, almost every country has built up its natural petroleum sources during few decades. However, the supply of motor fuel petrol or gasoline from all sources put together falls far short of the actual needs of a developing country. Therefore, the production of petrol by the synthetic method is engaging the attention of our organic chemists. The 'synthetic petrol' has been produced in Germany from coal, lignite, and other carbonaceous material. The chief methods used for preparing petrol from coal are:

• Fischer - Tropsch Process ( Reduction of Carbon monoxide )

This method was developed in 1923 by two German chemists, Franz Fischer and Hans Tropsch. Carbon monoxide needed in this process is made by passing steam over red-hot 'coke'. The water gas thus obtained is mixed with hydrogen and passed at a pressure of 5-10 atmospheres into a chamber containing a 'cobalt catalyst ' at 200-degree celsius. The product is a mixture consisting mainly of liquid hydrocarbons.

           nCO    +     ( 2n+1 ) H2              reaction                   Alkane    +    nH2O

                Reactants                                                                       Products 

The ' artificial petroleum ' so obtained is separated by fractional distillation, similar to the one used in Bergius process. The various fractions separated are petrol, kerosene oil, lubricating oil, diesel oil and paraffin wax.

• Bergius Process

In this method, finely powdered coal and a suitable catalyst is made into a paste with Heavy Oil produced in the process. The coal paste is then preheated and pumped to the converter. Here, the paste is heated to 450 degree Celsius and hydrogen bubbled through it at 250 atm pressure. The coal, which is really a mixture of high molecular complex organic compounds deficient in hydrogen, and elementary carbon, combines with hydrogen to form higher saturated compounds. These as a resulted of cracking and simultaneously hydrogenation yield a mixture of alkanes. Thus the vapours leaving the converter upon condensation yield ' Synthetic Petroleum ' or Crude Oil.This crude oil upon fractional distillation produces:

(1) Petrol; (2) Middle Oil; and (3) Heavy Oil. The Middle oil fraction is again hydrogenated in the vapour phase in contact with a solid catalyst to give more petrol. Actually, the second process yields four times the petrol obtained by the primary hydrogenation of coal.

The heavy oil obtained in the process is recirculated for making fresh coal paste. One ton of soft coal treated as above yields 140 gallons of petrol. The Bergius Process is at present the most promising of all methods so far invented for the production of synthetic motor fuel.       

  

How To Manufacture Ethyl Alcohol from Molasses

All over the world most of the ethyl alcohol is prepared from molasses. Molasses is the mother liquor left after the crystallization of cane sugar from concentrated juice. It is dark colored thick syrupy mass. Molasses contains about 60% fermentable sugars, mostly sucrose, glucose, and fructose. It forms an excellent cheap source of industrial ethyl alcohol. Molasses is converted into ethyl alcohol by the following steps:

• Dilution

Molasses is first diluted with water. One volume of molasses is mixed with five volumes of water.

• Addition of Ammonium Sulphate

Molasses usually contains enough nitrogenous matter to act as food for yeast during fermentation. If the nitrogen content of the molasses is poor, it may be fortified with ammonium sulphate or ammonium phosphate.

• Addition of Sulphuric Acid

The solution is then made acidic with a small amount of sulphuric acid. Acidity is favorable to the growth of yeast but unfavorable to most other bacteria. Care should be taken to avoid an excess of acid as the yeast may be killed.

• Addition of Yeast ( Fermentation )

The resulting solution is received in a large fermentation tank and yeast is added to it. The mixture is maintained at about 30-degree celsius for 2 or 3 days. During this period the enzymes invertase and zymase present in yeast bring about the conversion of sugars into ethyl alcohol. During the process, the liquor froths owing to the evolution of carbon dioxide. The fermented liquor is known as WASH.

• Fractional Distillation of Wash

The wash contains 15-18% ethyl alcohol. It is subjected to fractional distillation in a special column. The column is divided into a number of compartments by means of plates. These plates are provided with valves and dropping tubes. Wash is admitted near the top. As it travels down the column, it meets the up-coming current of steam, The steam converts ethyl alcohol into vapors. These vapors rise up and are fed into the condenser. The high boiling impurities travel down the column. The fractional distillation of the wash yields three fractions:

Fraction 1. Low boiling fraction is drawn from the head of the column. It consists of acetaldehyde.

Fraction 2. The main fraction is drawn near the top of the column. It consists of 95% ethyl alcohol. It is sold under the name Rectified Spirit or Commercial Alcohol.

Fraction 3. High boiling fraction ( 125-140 ) degree celsius drawn near the base of the column. It is called Fusel Oil. It consists mainly of amyl alcohol. 
  

How To Manufacture Ethyl Alcohol from Starch

The important raw materials containing starch are potatoes, rice, maize, and barley. Of these potatoes are commonly used for the manufacture of ethyl alcohol. The process involves following steps.

• Liberation of starch

Potatoes are cut into slices and crushed. The crushed mass is then steamed at 140-150 temperature degree centigrade under pressure. In this way, the cell walls containing starch particles are broken and starch brought into solution. The resulting solution is called MASH.

• Hydrolysis of Starch to Maltose

The enzyme diastase is needed to hydrolysed starch to maltose. It is present in small amounts in barley and can be developed considerably upon germination. For this purpose, barley is steeped in water at a temperature of 10-13 degree celsius for a couple of days. This is then taken out and allowed to germinate in dark at about 15 degrees C. Barely is then heated to 60-degree celsius to stop germination. The dried and germinated barley is known as MALT. 

To the MASH obtained from step ( 1 ) is now added MALT and the temperature are raised to 50-60 degree celsius. Within half an hour diastase present in the MALT converts the starch to maltose.

2( C6 H10 O5 )n + nH2 O               Diastase            nC12 H22 O11

      Starch                                                                       Maltose

• Fermentation of Maltose to Ethyl Alcohol

Yeast is next added to the Maltose solution. It furnishes the enzymes maltase and zymase, While the former converts maltose into glucose, the latter converts glucose into ethyl alcohol.

• Fractional Distillation of Wash

The fermented liquid or wash obtained above is then subjected to fractional distillation as describe before. The product is 95% ethyl alcohol ( Rectified Spirit ).

    Absolute Alcohol. Absolute ethyl alcohol is 100% pure ethyl alcohol. Commercial alcohol ( Rectified Spirit ) is a mixture of 95% ethyl alcohol and 5% water. This mixture can not be separated by further distillation. Such a solution is called Azeotropic Mixture or Azeotrope. 

How To Manufacture Sucrose from Sugar Cane

Sucrose is ordinary table sugar. It occurs chiefly in sugar cane and sugar beets. In smaller amount it is present in maple sap, honey, and several fruits.

Manufacture of Sucrose ( Table Sugar )

In Pakistan and other tropical countries, the main source of sucrose is sugar cane. The modern method for the manufacture of ' Direct Consumption ' sugar from cane consists of the following steps.

• Juice Extraction 

The crushed cane is passed through a roller mill to squeeze out juice. The partially exhausted ' cane mat ' emerging from the mill is passed on to a tank, called Diffuser, by a chain conveyor . Here the maximum extraction of sucrose is done by washing with hot water and dilute juice on counter-current principle. This technique gets sugar extraction up to 98 per cent. The cellulosic material discharged from the diffuser is called Bagasse and is used as fuel under boilers.

• Juice Purification 

The raw juice contains 14-25 per cent sucrose and much impurity such as organic acids, inorganic salts, proteins, and colouring matter. It is purified by the operations listed below:

            1)Defecation: The juice is heated with high pressure steam and treated with 2-3 percent lime in a steel tank. This operation called defecation throws out organic acids as insoluble calcium salts , coagulated protein and colouring matter. The precipitate is removed by filtration.

           2)Carbonation: Through the filtered juice is then passed carbon dioxide. This operation known as carbonation, removes the excess, of lime as calcium carbonate which entraps colouring matter, colloidals, and some inorganic salts. The ' mud ' that settles is separated by filtration.

           3)Decolorisation: In Pakistan, the clarified juice is decolorised by treating with sulphur dioxide. This operation called sulphitation while it bleaches the brown colour of the juice, completes the neutralisation of lime. The insoluble calcium sulphite is removed by filtration.

The brown colour juice is also decolorised by percolation through beds of adsorbents, for instance, bone char, granular carbon, and ion exchange resins.

• Concentration and Crystallisation

The clear solution is then concentrated by boiling under reduced pressure in Multiple Effect Evaporation. In these, the steam produced in the first evaporator is used to boil the juice in the second maintained at a lower pressure.

The concentrated juice is finally passed to the Vacuum Pan where further evaporation reduces the water content to 6-8 per cent. Here partial separation of crystals takes place, The mixture of syrup and crystals, known as Massecuit, is then discharged into a large tank, the Crystallising Tank, fitted with cooling pipes. The crystals grow and form a thick crop.

• Separation of Crystals by Centrifugation, and Drying

The massecuite is then sent to centrifuges whereby sugar crystals are separated from the syrup. The crystals are here sprinkled with a little water to wash any syrup sticking to the surface. The wet sugar is dried by passing down a rotating drum with steam of hot air flowing counter-current to it. The residual mother liquor, from which the crystals have been removed, is called Molasses.