Helianthus or sunflowers BEAUTY

Helianthus or sunflowers (from the Greek: ήλιος, Hēlios, "sun" and ανθός, anthos, "flower") L. /ˌhiːliˈænθəs/ is a genus of plants comprising about 70 species in the family Asteraceae, all of which are native to North America except three species in South America. The common name, "sunflower," also applies to the popular annual species Helianthus annuus, the common sunflower. This and other species, notably Jerusalem artichoke (H. tuberosus), are cultivated in temperate regions as food crops and ornamental plants.

The genus is one of many in the Asteraceae that are known as sunflowers. It is distinguished technically by the fact that the ray flowers, when present, are sterile, and by the presence on the disk flowers of a pappus that is of two awn-like scales that are caducous (that is, easily detached and falling at maturity). Some species also have additional shorter scales in the pappus, and there is one species that lacks a pappus entirely. Another technical feature that distinguishes the genus more reliably, but requires a microscope to see, is the presence of a prominent, multicellular appendage at the apex of the style. Sunflowers are especially well known for their symmetry based on Fibonacci numbers and the Golden angle.

There is quite a bit of variability among the perennial species that make up the bulk of the species in the genus. Some have most or all of the large leaves in a rosette at the base of the plant and produce a flowering stem that has leaves that are reduced in size. Most of the perennials have disk flowers that are entirely yellow, but a few have disk flowers with reddish lobes. One species, H. radula, lacks ray flowers altogether.

The domesticated sunflower, H. annuus, is the most familiar species. Perennial sunflower species are not as popular for gardens due to their tendency to spread rapidly and become invasive. Whorled sunflowers, H. verticillatus, were listed as an endangered species in 2014 when the U.S. Fish and Wildlife Service issued a final rule protecting it under the Endangered Species Act. The primary threats are industrial forestry and pine plantations in Alabama, Georgia, and Tennessee. They grow to six feet tall and are primarily found in woodlands, adjacent to creeks and moist, prairie-like areas.

Sunflowers are usually tall annuals, that grow to a height of 50–400 centimetres (20–157 in).

The rough and hairy stem is branched in the upper part in wild plants but is usually unbranched in domesticated cultivars. The petiolate leaves are dentate and often sticky. The lower leaves are opposite, ovate or often heart-shaped. The upper leaves are alternate and narrower.

They bear one or several to many wide, terminal capitula (flower heads), with bright yellow ray florets at the outside and yellow or maroon (also known as a brown/red) disc florets inside. Several ornamental cultivars have red-colored ray florets; all of them stem from a single original mutant.During growth, sunflowers tilt during the day to face the sun, but stop once they begin blooming. This tracking of the sun in young sunflower heads is called heliotropism. By the time they are mature, sunflowers generally face east.

Helianthus species are used as food plants by the larvae of many lepidopterans.

A vegetable.

PLANTS IN HOME VEGETABLE GARDEN

Myocardial infarction diagnosis

A diagnosis of myocardial infarction is created by integrating the history of the presenting illness and physical examination with electrocardiogram findings and cardiac markers (blood tests for heart muscle cell damage). A coronary angiogram allows visualization of narrowings or obstructions on the heart vessels, and therapeutic measures can follow immediately. At autopsy, a pathologist can diagnose a myocardial infarction based on anatomopathological findings.

A chest radiograph and routine blood tests may indicate complications or precipitating causes and are often performed upon arrival to an emergency department. New regional wall motion abnormalities on an echocardiogram are also suggestive of a myocardial infarction. Echo may be performed in equivocal cases by the on-call cardiologist.In stable patients whose symptoms have resolved by the time of evaluation, Technetium (99mTc) sestamibi (i.e. a "MIBI scan") or thallium-201 chloride can be used in nuclear medicine to visualize areas of reduced blood flow in conjunction with physiologic or pharmocologic stress.Thallium may also be used to determine viability of tissue, distinguishing whether non-functional myocardium is actually dead or merely in a state of hibernation or of being stunned.

According to the WHO criteria as revised in 2000, a cardiac troponin rise accompanied by either typical symptoms, pathological Q waves, ST elevation or depression or coronary intervention are diagnostic of MI.

Previous WHO criteria formulated in 1979 put less emphasis on cardiac biomarkers; according to these, a patient is diagnosed with myocardial infarction if two (probable) or three (definite) of the following criteria are satisfied:

Clinical history of ischaemic type chest pain lasting for more than 20 minutes

Changes in serial ECG tracings

Rise and fall of serum cardiac biomarkers such as creatine kinase-MB fraction and troponin.

The general appearance of patients may vary according to the experienced symptoms; the patient may be comfortable, or restless and in severe distress with an increased respiratory rate. A cool and pale skin is common and points to vasoconstriction. Some patients have low-grade fever (38–39 °C). Blood pressure may be elevated or decreased, and the pulse can become irregular.

If heart failure ensues, elevated jugular venous pressure and hepatojugular reflux, or swelling of the legs due to peripheral edema may be found on inspection. Rarely, a cardiac bulge with a pace different from the pulse rhythm can be felt on precordial examination. Various abnormalities can be found on auscultation, such as a third and fourth heart sound, systolic murmurs, paradoxical splitting of the second heart sound, a pericardial friction rub and rales over the lung.

The primary purpose of the electrocardiogram is to detect ischemia or acute coronary injury in broad, symptomatic emergency department populations. A serial ECG may be used to follow rapid changes in time. The standard 12 lead ECG does not directly examine the right ventricle, and is relatively poor at examining the posterior basal and lateral walls of the left ventricle. In particular, acute myocardial infarction in the distribution of the circumflex artery is likely to produce a nondiagnostic ECG. The use of additional ECG leads like right-sided leads V3R and V4R and posterior leads V7, V8, and V9 may improve sensitivity for right ventricular and posterior myocardial infarction.

The 12 lead ECG is used to classify patients into one of three groups:

those with ST segment elevation or new bundle branch block (suspicious for acute injury and a possible candidate for acute reperfusion therapy with thrombolytics or primary PCI),

those with ST segment depression or T wave inversion (suspicious for ischemia), and

those with a so-called non-diagnostic or normal ECG.

A normal ECG does not rule out acute myocardial infarction. Mistakes in interpretation are relatively common, and the failure to identify high risk features has a negative effect on the quality of patient care.

It should be determined if a person is at high risk for myocardial infarction before conducting imaging tests to make a diagnosis.People who have a normal ECG and who are able to exercise, for example, do not merit routine imaging. Imaging tests such as stress radionuclide myocardial perfusion imaging or stress echocardiography can confirm a diagnosis when a person's history, physical exam, ECG and cardiac biomarkers suggest the likelihood of a problem.

Cardiac markers or cardiac enzymes are proteins that leak out of injured myocardial cells through their damaged cell membranes into the bloodstream. Until the 1980s, the enzymes SGOT and LDH were used to assess cardiac injury. Now, the markers most widely used in detection of MI are MB subtype of the enzyme creatine kinase and cardiac troponins T and I as they are more specific for myocardial injury. The cardiac troponins T and I which are released within 4–6 hours of an attack of MI and remain elevated for up to 2 weeks, have nearly complete tissue specificity and are now the preferred markers for assessing myocardial damage. Heart-type fatty acid binding protein is another marker, used in some home test kits. Elevated troponins in the setting of chest pain may accurately predict a high likelihood of a myocardial infarction in the near future New markers such as glycogen phosphorylase isoenzyme BB are under investigation.

The diagnosis of myocardial infarction requires two out of three components (history, ECG, and enzymes). When damage to the heart occurs, levels of cardiac markers rise over time, which is why blood tests for them are taken over a 24-hour period. Because these enzyme levels are not elevated immediately following a heart attack, patients presenting with chest pain are generally treated with the assumption that a myocardial infarction has occurred and then evaluated for a more precise diagnosis