The electromagnetic spectrum covers electromagnetic waves with frequencies ranging from below one hertz to above 1025 hertz, corresponding to wavelengths from thousands of kilometers down to a fraction of the size of an atomic nucleus.
روش کیفی طیف وسیعی ازپژوهش ها را تشکیل میدهند که از نظر پارادایم نوع پرسشهای پژوهش و هم از نظر نحوه گردآوری داده و عمق پژوهش، باپوژهش های کمی تفاوت دارند.
این نوع پژوهش قصد تعمیم پژوهش نداشته و درصدد از جرایی وقوع پدیده ها است. با وجود این که شیوه انجام این نوع پژوهش از ساخت انجام پژوهش های کیفی برخوردار نیست، ولی در سال های اخیر بسیار موردتوجه پژوهشگران قرار گرفته و در کشورمان نیز از اقبال خوبی برخوردار شده است.
- کازمتیک - پیری و تئوری تلومراز- دکتر محمد بقایی داروساز Mohammad Baghaei
مدل پایه ای تلومر سلولی قدیمی ترین فرضیه سلولی است. تلومر ها توالی تکراری DNA در انتهای کروموزوم های خطی هستند. تلومراز نوعی آنزیم RNA وابسته به DNAپلیمراز می باشد( یک ترانس کریپتاز معکوس سلولی ) که قالب RNA را برای ساخت DNA حمل می کند بنا بر این تولومراز یک ریبو نوکلئوپروتئین است که به طویل سازی تولومر در سلولهایی که فعالیت می کنند کمک می نماید.
روش کیفی طیف وسیعی ازپژوهش ها را تشکیل میدهند که از نظر پارادایم نوع پرسشهای پژوهش و هم از نظر نحوه گردآوری داده و عمق پژوهش، باپوژهش های کمی تفاوت دارند.
این نوع پژوهش قصد تعمیم پژوهش نداشته و درصدد از جرایی وقوع پدیده ها است. با وجود این که شیوه انجام این نوع پژوهش از ساخت انجام پژوهش های کیفی برخوردار نیست، ولی در سال های اخیر بسیار موردتوجه پژوهشگران قرار گرفته و در کشورمان نیز از اقبال خوبی برخوردار شده است.
- کازمتیک - پیری و تئوری تلومراز- دکتر محمد بقایی داروساز Mohammad Baghaei
مدل پایه ای تلومر سلولی قدیمی ترین فرضیه سلولی است. تلومر ها توالی تکراری DNA در انتهای کروموزوم های خطی هستند. تلومراز نوعی آنزیم RNA وابسته به DNAپلیمراز می باشد( یک ترانس کریپتاز معکوس سلولی ) که قالب RNA را برای ساخت DNA حمل می کند بنا بر این تولومراز یک ریبو نوکلئوپروتئین است که به طویل سازی تولومر در سلولهایی که فعالیت می کنند کمک می نماید.
Diathermy is electrically induced heat or the use of high-frequency electromagnetic currents as a form of physical therapy and in surgical procedures. The field was pioneered in 1907 by German physician Karl Franz Nagelschmidt, who coined the term diathermy from the Greek words dia and therma, literally meaning "heating through.
Diathermy is commonly used for muscle relaxation, and to induce deep heating in tissue for therapeutic purposes in medicine. It is used in physical therapy to deliver moderate heat directly to pathologic lesions in the deeper tissues of the body.
Diathermy is produced by three techniques: ultrasound (ultrasonic diathermy), short-wave radio frequencies in the range 1–100 MHz (shortwave diathermy) or microwaves typically in the 915 MHz or 2.45 GHz bands (microwave diathermy), the methods differing mainly in their penetration capability. It exerts physical effects and elicits a spectrum of physiological responses.
The same techniques are also used to create higher tissue temperatures to destroy neoplasms (cancer and tumors), warts, and infected tissues; this is called hyperthermia treatment. In surgery diathermy is used to cauterize blood vessels to prevent excessive bleeding. The technique is particularly valuable in neurosurgery and surgery of the eye.
X-rays make up X-radiation, a form of electromagnetic radiation. Most X-rays have a wavelength ranging from 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3×1016 Hz to 3×1019 Hz) and energies in the range 100 eV to 100 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. In many languages, X-radiation is referred to with terms meaning Röntgen radiation, after the German scientist Wilhelm Röntgen who discovered these on November 8, 1895, who usually is credited as its discoverer, and who named it X-radiation to signify an unknown type of radiation.Spelling of X-ray(s) in the English language includes the variants x-ray(s), xray(s), and X ray(s).
Eyes are organs of the visual system. They provide organisms with vision, the ability to receive and process visual detail, as well as enabling several photo response functions that are independent of vision. Eyes detect light and convert it into electro-chemical impulses in neurons. In higher organisms, the eye is a complex optical system which collects light from the surrounding environment, regulates its intensity through a diaphragm, focuses it through an adjustable assembly of lenses to form an image, converts this image into a set of electrical signals, and transmits these signals to the brain through complex neural pathways that connect the eye via the optic nerve to the visual cortex and other areas of the brain. Eyes with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in molluscs, chordates and arthropods.
Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except in that humans cannot hear it. This limit varies from person to person and is approximately 20 kilohertz (20,000 hertz) in healthy young adults. Ultrasound devices operate with frequencies from 20 kHz up to several gigahertz.
Ultrasound is used in many different fields. Ultrasonic devices are used to detect objects and measure distances. Ultrasound imaging or sonography is often used in medicine. In the nondestructive testing of products and structures, ultrasound is used to detect invisible flaws. Industrially, ultrasound is used for cleaning, mixing, and to accelerate chemical processes. Animals such as bats and porpoises use ultrasound for locating prey and obstacles. Scientists are also studying ultrasound using graphene diaphragms as a method of communication.
Nuclear medicine is a medical specialty involving the application of radioactive substances in the diagnosis and treatment of disease. Nuclear medicine, in a sense, is "radiology done inside out" or "endoradiology" because it records radiation emitting from within the body rather than radiation that is generated by external sources like X-rays. In addition, nuclear medicine scans differ from radiology as the emphasis is not on imaging anatomy but the function and for such reason, it is called a physiological imaging modality. Single photon emission computed tomography (SPECT) and positron emission tomography (PET) scans are the two most common imaging modalities in nuclear medicine.
A positron emission tomography (PET) scan is an imaging test that allows your doctor to check for diseases in your body.
The scan uses a special dye containing radioactive tracers. These tracers are either swallowed, inhaled, or injected into a vein in your arm depending on what part of the body is being examined. Certain organs and tissues then absorb the tracer.
When detected by a PET scanner, the tracers help your doctor to see how well your organs and tissues are working.
The tracer will collect in areas of higher chemical activity, which is helpful because certain tissues of the body, and certain diseases, have a higher level of chemical activity. These areas of disease will show up as bright spots on the PET scan.
The PET scan can measure blood flow, oxygen use, how your body uses sugar, and much more.
A PET scan is typically an outpatient procedure. This means you can go about your day after the test is finished.
In the United States, around 2 million PET scans are performed each year.
Medical physics (also called biomedical physics, medical biophysics or applied physics in medicine) is, in general, the application of physics concepts, theories, and methods to medicine or healthcare. Medical physics departments may be found in hospitals or universities.
Symbiotic bacteria are bacteria living in symbiosis with another organism or each other. For example, Zoamastogopera, found in the stomach of termites, enable them to digest cellulose.
Environmental microbiology is the study of microbial processes in the environment, microbial communities and microbial interactions. This includes:
Structure and activities of microbial communities
Microbial interactions and interactions with macroorganisms
Population biology of microorganisms
Microbes and surfaces (adhesion and biofilm formation)
Microbial community genetics and evolutionary processes
(Global) element cycles and biogeochemical processes
Microbial life in extreme and unusual little-explored environments
Virus classification is the process of naming viruses and placing them into a taxonomic system. Similar to the classification systems used for cellular organisms, virus classification is the subject of ongoing debate and proposals. This is mainly due to the pseudo-living nature of viruses, which is to say they are non-living particles with some chemical characteristics similar to those of life. As such, they do not fit neatly into the established biological classification system in place for cellular organisms.
Viruses are mainly classified by phenotypic characteristics, such as morphology, nucleic acid type, mode of replication, host organisms, and the type of disease they cause. Currently, two main schemes are used for the classification of viruses: the International Committee on Taxonomy of Viruses (ICTV) system and Baltimore classification system, which places viruses into one of seven groups. Accompanying this broad method of classification are specific naming conventions and further classification guidelines set out by the ICTV.
Viral replication is the formation of biological viruses during the infection process in the target host cells. Viruses must first get into the cell before viral replication can occur. From the perspective of the virus, the purpose of viral replication is to allow production and survival of its kind. By generating abundant copies of its genome and packaging these copies into viruses, the virus is able to continue infecting new hosts. Replication between viruses is greatly varied and depends on the type of genes involved in them. Most DNA viruses assemble in the nucleus while most RNA viruses develop solely in cytoplasm
This document discusses protoplast isolation and cell culture. It begins by defining a protoplast as a plant cell without a cell wall that contains normal cell organelles. Protoplasts can be isolated from actively growing tissues using mechanical and enzymatic methods. The mechanical method involves plasmolysis and cutting of tissues, while the enzymatic method uses lytic enzymes to remove the cell wall. Cell culture methods are also discussed, including primary cell cultures derived directly from tissues that have a finite lifespan, and continuous cell lines derived from tumors that can divide indefinitely. Different cell types, culture media, and tissue culture techniques are described.
Virology is the study of viruses – submicroscopic, parasitic particles of genetic material contained in a protein coat and virus-like agents. It focuses on the following aspects of viruses: their structure, classification and evolution, their ways to infect and exploit host cells for reproduction, their interaction with host organism physiology and immunity, the diseases they cause, the techniques to isolate and culture them, and their use in research and therapy. Virology is considered to be a subfield of microbiology or of medicine.
Diathermy is electrically induced heat or the use of high-frequency electromagnetic currents as a form of physical therapy and in surgical procedures. The field was pioneered in 1907 by German physician Karl Franz Nagelschmidt, who coined the term diathermy from the Greek words dia and therma, literally meaning "heating through.
Diathermy is commonly used for muscle relaxation, and to induce deep heating in tissue for therapeutic purposes in medicine. It is used in physical therapy to deliver moderate heat directly to pathologic lesions in the deeper tissues of the body.
Diathermy is produced by three techniques: ultrasound (ultrasonic diathermy), short-wave radio frequencies in the range 1–100 MHz (shortwave diathermy) or microwaves typically in the 915 MHz or 2.45 GHz bands (microwave diathermy), the methods differing mainly in their penetration capability. It exerts physical effects and elicits a spectrum of physiological responses.
The same techniques are also used to create higher tissue temperatures to destroy neoplasms (cancer and tumors), warts, and infected tissues; this is called hyperthermia treatment. In surgery diathermy is used to cauterize blood vessels to prevent excessive bleeding. The technique is particularly valuable in neurosurgery and surgery of the eye.
X-rays make up X-radiation, a form of electromagnetic radiation. Most X-rays have a wavelength ranging from 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz (3×1016 Hz to 3×1019 Hz) and energies in the range 100 eV to 100 keV. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. In many languages, X-radiation is referred to with terms meaning Röntgen radiation, after the German scientist Wilhelm Röntgen who discovered these on November 8, 1895, who usually is credited as its discoverer, and who named it X-radiation to signify an unknown type of radiation.Spelling of X-ray(s) in the English language includes the variants x-ray(s), xray(s), and X ray(s).
Eyes are organs of the visual system. They provide organisms with vision, the ability to receive and process visual detail, as well as enabling several photo response functions that are independent of vision. Eyes detect light and convert it into electro-chemical impulses in neurons. In higher organisms, the eye is a complex optical system which collects light from the surrounding environment, regulates its intensity through a diaphragm, focuses it through an adjustable assembly of lenses to form an image, converts this image into a set of electrical signals, and transmits these signals to the brain through complex neural pathways that connect the eye via the optic nerve to the visual cortex and other areas of the brain. Eyes with resolving power have come in ten fundamentally different forms, and 96% of animal species possess a complex optical system. Image-resolving eyes are present in molluscs, chordates and arthropods.
Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing. Ultrasound is not different from "normal" (audible) sound in its physical properties, except in that humans cannot hear it. This limit varies from person to person and is approximately 20 kilohertz (20,000 hertz) in healthy young adults. Ultrasound devices operate with frequencies from 20 kHz up to several gigahertz.
Ultrasound is used in many different fields. Ultrasonic devices are used to detect objects and measure distances. Ultrasound imaging or sonography is often used in medicine. In the nondestructive testing of products and structures, ultrasound is used to detect invisible flaws. Industrially, ultrasound is used for cleaning, mixing, and to accelerate chemical processes. Animals such as bats and porpoises use ultrasound for locating prey and obstacles. Scientists are also studying ultrasound using graphene diaphragms as a method of communication.
Nuclear medicine is a medical specialty involving the application of radioactive substances in the diagnosis and treatment of disease. Nuclear medicine, in a sense, is "radiology done inside out" or "endoradiology" because it records radiation emitting from within the body rather than radiation that is generated by external sources like X-rays. In addition, nuclear medicine scans differ from radiology as the emphasis is not on imaging anatomy but the function and for such reason, it is called a physiological imaging modality. Single photon emission computed tomography (SPECT) and positron emission tomography (PET) scans are the two most common imaging modalities in nuclear medicine.
A positron emission tomography (PET) scan is an imaging test that allows your doctor to check for diseases in your body.
The scan uses a special dye containing radioactive tracers. These tracers are either swallowed, inhaled, or injected into a vein in your arm depending on what part of the body is being examined. Certain organs and tissues then absorb the tracer.
When detected by a PET scanner, the tracers help your doctor to see how well your organs and tissues are working.
The tracer will collect in areas of higher chemical activity, which is helpful because certain tissues of the body, and certain diseases, have a higher level of chemical activity. These areas of disease will show up as bright spots on the PET scan.
The PET scan can measure blood flow, oxygen use, how your body uses sugar, and much more.
A PET scan is typically an outpatient procedure. This means you can go about your day after the test is finished.
In the United States, around 2 million PET scans are performed each year.
Medical physics (also called biomedical physics, medical biophysics or applied physics in medicine) is, in general, the application of physics concepts, theories, and methods to medicine or healthcare. Medical physics departments may be found in hospitals or universities.
Symbiotic bacteria are bacteria living in symbiosis with another organism or each other. For example, Zoamastogopera, found in the stomach of termites, enable them to digest cellulose.
Environmental microbiology is the study of microbial processes in the environment, microbial communities and microbial interactions. This includes:
Structure and activities of microbial communities
Microbial interactions and interactions with macroorganisms
Population biology of microorganisms
Microbes and surfaces (adhesion and biofilm formation)
Microbial community genetics and evolutionary processes
(Global) element cycles and biogeochemical processes
Microbial life in extreme and unusual little-explored environments
Virus classification is the process of naming viruses and placing them into a taxonomic system. Similar to the classification systems used for cellular organisms, virus classification is the subject of ongoing debate and proposals. This is mainly due to the pseudo-living nature of viruses, which is to say they are non-living particles with some chemical characteristics similar to those of life. As such, they do not fit neatly into the established biological classification system in place for cellular organisms.
Viruses are mainly classified by phenotypic characteristics, such as morphology, nucleic acid type, mode of replication, host organisms, and the type of disease they cause. Currently, two main schemes are used for the classification of viruses: the International Committee on Taxonomy of Viruses (ICTV) system and Baltimore classification system, which places viruses into one of seven groups. Accompanying this broad method of classification are specific naming conventions and further classification guidelines set out by the ICTV.
Viral replication is the formation of biological viruses during the infection process in the target host cells. Viruses must first get into the cell before viral replication can occur. From the perspective of the virus, the purpose of viral replication is to allow production and survival of its kind. By generating abundant copies of its genome and packaging these copies into viruses, the virus is able to continue infecting new hosts. Replication between viruses is greatly varied and depends on the type of genes involved in them. Most DNA viruses assemble in the nucleus while most RNA viruses develop solely in cytoplasm
This document discusses protoplast isolation and cell culture. It begins by defining a protoplast as a plant cell without a cell wall that contains normal cell organelles. Protoplasts can be isolated from actively growing tissues using mechanical and enzymatic methods. The mechanical method involves plasmolysis and cutting of tissues, while the enzymatic method uses lytic enzymes to remove the cell wall. Cell culture methods are also discussed, including primary cell cultures derived directly from tissues that have a finite lifespan, and continuous cell lines derived from tumors that can divide indefinitely. Different cell types, culture media, and tissue culture techniques are described.
Virology is the study of viruses – submicroscopic, parasitic particles of genetic material contained in a protein coat and virus-like agents. It focuses on the following aspects of viruses: their structure, classification and evolution, their ways to infect and exploit host cells for reproduction, their interaction with host organism physiology and immunity, the diseases they cause, the techniques to isolate and culture them, and their use in research and therapy. Virology is considered to be a subfield of microbiology or of medicine.