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Topic Review
Blood Typing
Blood typing is a medical laboratory test used to identify the antigens on a person's red blood cells, which determine their blood type. Routine blood typing involves determining the ABO and RhD (Rh factor) type, and is performed before blood transfusions to ensure that the donor blood is compatible. It is also used to help diagnose hemolytic disease of the newborn, a condition caused by incompatibility between the blood types of a mother and her baby. ABO typing involves both identification of ABO antigens on red blood cells (forward grouping) and identification of ABO antibodies in the plasma (reverse grouping). Other blood group antigens, such as RhC/c and E/e or Kell, may be tested for in special situations. Blood typing is usually performed using serologic methods, which use reagents containing antibodies, called antisera, to identify blood group antigens. Serologic methods rely on the ability of antibodies to cause red blood cells to clump together when they bind to antigens on the cell surface, a phenomenon called agglutination. A number of serologic methods are available, ranging from manual blood typing using test tubes or slides to fully automated systems. Blood types can also be determined through genetic testing, which is used when conditions that interfere with serologic testing are present or when a high degree of accuracy in antigen identification is required. A number of conditions can cause false or inconclusive results in blood typing. When these issues affect ABO typing, they are called ABO discrepancies. ABO discrepancies must be investigated and resolved before the person's blood type is reported. There are different procedures for resolving ABO discrepancies depending on the underlying causes. Other sources of error in blood typing include the "weak D" phenomenon, in which people who are positive for the RhD antigen show weak or negative reactions when tested for RhD, and the presence of Immunoglobulin G antibodies on red blood cells, which interferes with typing for some blood group antigens.
  • 4.8K
  • 25 Oct 2022
Topic Review
Soft Gelatin Capsules
The development of soft gelatin capsules (SGCs) dosage forms has attracted a great deal of interest in the oral delivery of poorly water-soluble drugs. This is attributed to the increased number of poorly soluble drugs in the pipeline, and hence the challenges of finding innovative ways of developing bioavailable and stable dosage forms. Encapsulation of these drugs into SGCs is one of the approaches that is utilized to deliver the active ingredients to the systemic circulation to overcome certain formulation hurdles. Once formulated, encapsulated drugs in the form of SGCs require suitable in vitro dissolution test methods to ensure drug product quality and performance.
  • 4.8K
  • 04 Mar 2021
Topic Review
Applications of Nanocellulose/Nanocarbon Composites: Focus on Biotechnology and Medicine
Nanocellulose/nanocarbon composites are newly-emerging smart hybrid materials containing cellulose nanoparticles, such as nanofibrils and nanocrystals, and carbon nanoparticles, such as “classical” carbon allotropes (fullerenes, graphene, nanotubes and nanodiamonds), or other carbon nanostructures (carbon nanofibers, carbon quantum dots, activated carbon and carbon black). The nanocellulose component acts as a dispersing agent and homogeneously distribute the carbon nanoparticles in aqueous environment. Nanocellulose/nanocarbon composites can be prepared with many advantageous properties, such as high mechanical strength, flexibility, stretchability, tunable thermal and electrical conductivity, tunable optical transparency, photodynamic and photothermal activity, nanoporous character and high adsorption capacity. They are therefore promising for a wide range of industrial applications, such as energy generation, storage and conversion, water purification, food packaging, construction of fire retardants and shape memory devices. They also hold great promise for biomedical applications, such as radical scavenging, photodynamic and photothermal therapy of tumors and microbial infections, drug delivery, biosensorics, isolation of various biomolecules, electrical stimulation of damaged tissues (e.g. cardiac, neural), neural and bone tissue engineering, engineering of blood vessels and advanced wound dressing, e.g. with antimicrobial and antitumor activity. However, the potential cytotoxicity and immunogenicity of the composites and their components must also be taken into account.
  • 4.7K
  • 01 Nov 2020
Topic Review
Coping (Psychology)
In psychology, coping means to invest own conscious effort, to solve personal and interpersonal problems, in order to try to master, minimize or tolerate stress and conflict. The psychological coping mechanisms are commonly termed coping strategies or coping skills. The term coping generally refers to adaptive (constructive) coping strategies. That is strategies which reduce stress. In contrast, other coping strategies may be coined as maladaptive, if they increase stress. Maladaptive coping is therefore also described, when looking at the outcome, as non-coping. Furthermore, the term coping generally refers to reactive coping, i.e. the coping response which follows the stressor. This differs from proactive coping, in which a coping response aims to neutralize a future stressor. Subconscious or non-conscious strategies (e.g. defense mechanisms) are generally excluded from the area of coping. The effectiveness of the coping effort depends on the type of stress, the individual, and the circumstances. Coping responses are partly controlled by personality (habitual traits), but also partly by the social environment, particularly the nature of the stressful environment.
  • 4.7K
  • 17 Oct 2022
Topic Review
Death Anxiety (Psychology)
Death anxiety is anxiety caused by thoughts of one's own death; it is also referred to as thanatophobia (fear of death). Death anxiety is different from necrophobia, the latter is the fear of others who are dead or dying, whereas the former concerns one's own death or dying. Popular psychotherapist Robert Langs proposed 3 different causes of death anxiety: Predatory, predator, and existential. In addition to his research, many theorists such as Sigmund Freud, Erik Erikson, Ernest Becker, and others have contemplated death and death anxiety and how it relates to human psychology. Death anxiety has been found to affect people of differing demographic groups as well; such as men versus women, young versus old, etc.    Additionally, there is anxiety caused by death-recent thought-content, which might be classified within a clinical setting by a psychiatrist as morbid and/or abnormal. This classification pre-necessitates a degree of anxiety which is persistent and interferes with everyday functioning. Lower ego integrity, more physical problems and more psychological problems are predictive of higher levels of death anxiety in elderly people perceiving themselves close to death. Death anxiety can cause extreme timidness with a person's attitude towards discussing anything to do with death. Findings from one systematic review demonstrated that death anxiety features across several mental health conditions. One meta-analysis of psychological interventions targeting death anxiety showed that death anxiety can be reduced using cognitive behavior therapy.
  • 4.7K
  • 20 Oct 2022
Topic Review
Stress
Stress, either physiological, biological or psychological, is an organism's response to a stressor such as an environmental condition. Stress is the body's method of reacting to a condition such as a threat, challenge or physical and psychological barrier. There are two hormones that an individual produces during a stressful situation, these are well known as adrenaline and cortisol. Stimuli that alter an organism's environment are responded to by multiple systems in the body. In humans and most mammals, the autonomic nervous system and hypothalamic-pituitary-adrenal (HPA) axis are the two major systems that respond to stress. The sympathoadrenal medullary (SAM) axis may activate the fight-or-flight response through the sympathetic nervous system, which dedicates energy to more relevant bodily systems to acute adaptation to stress, while the parasympathetic nervous system returadrenaliney to homeostasis. The second major physiological stress-response center, the HPA axis, regulates the release of cortisol, which influences many bodily functions such as metabolic, psychological and immunological functions. The SAM and HPA axes are regulated by several brain regions, including the limbic system, prefrontal cortex, amygdala, hypothalamus, and stria terminalis. Through these mechanisms, stress can alter memory functions, reward, immune function, metabolism and susceptibility to diseases. Disease risk is particularly pertinent to mental illnesses, whereby chronic or severe stress remains a common risk factor for several mental illnesses. One system suggests there are five types of stress labeled "acute time-limited stressors", "brief naturalistic stressors", "stressful event sequences", "chronic stressors", and "distant stressors". An acute time-limited stressor involves a short-term challenge, while a brief natural stressor involves an event that is normal but nevertheless challenging. A stressful event sequence is a stressor that occurs, and then continues to yield stress into the immediate future. A chronic stressor involves exposure to a long-term stressor, and a distant stressor is a stressor that is not immediate.
  • 4.6K
  • 28 Oct 2022
Topic Review
Pulmonary Artery Catheter
Pulmonary artery catheterization (PAC), or right heart catheterization, is the insertion of a catheter into a pulmonary artery. Its purpose is diagnostic; it is used to detect heart failure or sepsis, monitor therapy, and evaluate the effects of drugs. The pulmonary artery catheter allows direct, simultaneous measurement of pressures in the right atrium, right ventricle, pulmonary artery, and the filling pressure ("wedge" pressure) of the left atrium. The pulmonary artery catheter is frequently referred to as a Swan-Ganz catheter, in honor of its inventors Jeremy Swan and William Ganz, from Cedars-Sinai Medical Center.
  • 4.5K
  • 24 Nov 2022
Topic Review
Mindfulness
Mindfulness is the psychological process of purposely bringing one's attention to experiences occurring in the present moment without judgment which one develops through the practice of meditation and through other training. Mindfulness derives from sati, a significant element of Buddhist traditions, and based on Zen, Vipassanā, and Tibetan meditation techniques. Though definitions and techniques of mindfulness are wide-ranging, Buddhist traditions explain what constitutes mindfulness such as how past, present and future moments arise and cease as momentary sense impressions and mental phenomena. Individuals who have contributed to the popularity of mindfulness in the modern Western context include Thích Nhất Hạnh (1926– ), Herbert Benson (1935– ), Jon Kabat-Zinn (1944– ), and Richard J. Davidson (1951– ). Clinical psychology and psychiatry since the 1970s have developed a number of therapeutic applications based on mindfulness for helping people experiencing a variety of psychological conditions. Mindfulness practice has been employed to reduce depression, to reduce stress, anxiety, and in the treatment of drug addiction. Programs based on mindfulness models have been adopted within schools, prisons, hospitals, veterans' centers, and other environments, and mindfulness programs have been applied for additional outcomes such as for healthy aging, weight management, athletic performance, helping children with special needs, and as an intervention during the perinatal period. Clinical studies have documented both physical- and mental-health benefits of mindfulness in different patient categories as well as in healthy adults and children. Research studies have shown a positive relationship between trait mindfulness (see below) and psychological health. The practice of mindfulness appears to provide therapeutic benefits to people with psychiatric disorders, including moderate benefits to those with psychosis. Studies also indicate that rumination and worry contribute to a variety of mental disorders, and that mindfulness-based interventions can reduce both rumination and worry. Further, the practice of mindfulness may be a preventive strategy to halt the development of mental-health problems. There is also evidence that suggest engaging in mindfulness meditation may influence physical health. For example, the psychological habit of repeatedly dwelling on stressful thoughts (i.e., rumination) appears to intensify the physiological effects of the stressor (as a result of the continual activation of the sympathetic nervous system and the hypothalamus-pituitary-adrenal axis) with the potential to lead to physical health related clinical manifestations. Studies indicate that mindfulness meditation, which brings about reductions in rumination, may alter these biological clinical pathways. Further, research indicates that mindfulness may favourably influence the immune system as well as inflammation,Cite error: Closing missing for tag
  • 4.5K
  • 12 Oct 2022
Topic Review
DESCRIPTION OF THE MITOCHONDRIAL PORIN VDAC1 AND ITS DISEASE RELEVANCE
Mitochondrial porins or voltage-dependent anionic channels (VDAC) are nonspecific channels that determine the permeability of the mitochondrial outer membrane (MEM). Its molecular mass oscillates around 28 to 36 kDa. These channels represent the most abundant proteins of the MEM. They are freely permeable to hydrophilic solutes and the limit of exclusion of metabolites is 3 to 6 kDa. These channels are the main route for the diffusion of ions such as pyruvate and ATP, among others. It has been proposed that the transport of these metabolites regulates the cellular energy supply. This review focus on some of the main aspects of the VDAC porins and its relevance in some physiological processes related with cancer and neurodegeneration diseases. 
  • 4.5K
  • 30 Oct 2020
Topic Review
Nonparametric Limits of Agreement
The assessment of agreement in method comparison and observer variability analysis of quantitative measurements is usually done by the Bland-Altman Limits of Agreement, where the paired differences are implicitly assumed to follow a normal distribution. Whenever this assumption does not hold, the 2.5% and 97.5% percentiles are obtained by quantile estimation. In the literature, empirical quantiles have been used for this purpose. In this simulation study, we applied both sample, subsampling, and kernel quantile estimators as well as other methods for quantile estimation to sample sizes between 30 and 150 and different distributions of the paired differences. The performance of 15 estimators in generating prediction intervals was measured by their respective coverage probability for one newly generated observation. Our results indicated that sample quantile estimators based on one or two order statistics outperformed all the other estimators and can be used for deriving nonparametric Limits of Agreement. For sample sizes exceeding 80 observations, more advanced quantile estimators, such as the Harrell-Davis and estimators of Sfakianakis-Verginis type, which use all the observed differences, performed likewise well, but may be considered intuitively more appealing than simple sample quantile estimators that are based on only two observations per quantile.
  • 4.4K
  • 27 Oct 2020
Topic Review
Health-Promoting Beverages
Tea, a beverage made from the processed leaves of the tea plant, Camellia sinensis, and herbal infusions, were primarily consumed to their pleasant taste. Nowadays, are also consumed due to the existence of nutraceutical compounds in the herbs used, such as polyphenols.
  • 4.4K
  • 30 Oct 2020
Topic Review
Generalizing the Local Average Treatment Effect
The local average treatment effect (LATE), also known as the complier average causal effect (CACE), refers to the treatment effect among compliers. The LATE may not be of the same value as the average treatment effect (ATE), so extrapolating the LATE directly should be done cautiously. In addition, the LATE retrieved from an experiment may not immediately be externally valid, especially when there is a case for treatment effect heterogeneity (i.e. the treatment effect varies across individuals).  However, generalizing the LATE through reweighting can be attempted, given certain key assumptions.
  • 4.3K
  • 30 Oct 2022
Topic Review
Immigrant Paradox
The immigrant paradox is that recent immigrants often outperform more established immigrants and non-immigrants on a number of health-, education-, and conduct- or crime-related outcomes, despite the numerous barriers they face to successful social integration. According to the UN, the number of first-generation immigrants worldwide is 244 million. These large-scale population changes worldwide have led many scholars, across fields, to study the acculturation and adjustment of immigrants to their new homes. Specifically, researchers have examined immigrant experiences as they pertain to educational attainment, mental and physical health, and conduct/crime. Researchers have tried to understand why later generations seem to perform less well than their forebears. They have found that it can be explained by non-optimal methodology and differences in the way generations are modified by the host culture.
  • 4.2K
  • 29 Nov 2022
Topic Review
Multi-Drug Resistance
Multidrug-resistance is a long debated term. Since 1980 it was used to imply the resistance of a microorganism to multiple pharmaceutical agents, without the number or types of antimicrobials being specified.Currently, the most widely accepted definition of multidrug-resistant (MDR) bacteria include a lack of susceptibility in three or more antimicrobial categories active against the isolated microorganism.
  • 4.2K
  • 27 Aug 2020
Topic Review
2014 Taiwan Food Scandal
The 2014 Taiwan food scandal refers to a series of food safety incidents in Taiwan that came to light in 2014. Adulteration of cooking oil with recycled waste oil and animal feed oil was discovered in September 2014. Despite coming to light only in 2014, mass food adulteration by Taiwanese food conglomerates, however, has been suppressed for decades, and the food safety crisis has been among the reasons for the electoral defeat of the Kuomintang in late 2014. At least 1,256 businesses were affected in the gutter oil scandal. In November 2014, it was found that dried tofu products (a.k.a. dougan 豆乾) have been adulterated with an industrial dye, methyl yellow (a.k.a. dimethyl), for some 20 years. In December 2014, it was furthermore found that even regular non-dyed tofu has been found contaminated with carcinogens, resulting in over 25,000 kg recalled.
  • 4.1K
  • 28 Nov 2022
Topic Review
Stuttering
Stuttering, also known as stammering, is a speech disorder in which the flow of speech is disrupted by involuntary repetitions and prolongations of sounds, syllables, words, or phrases as well as involuntary silent pauses or blocks in which the person who stutters is unable to produce sounds. The term stuttering is most commonly associated with involuntary sound repetition, but it also encompasses the abnormal hesitation or pausing before speech, referred to by people who stutter as blocks, and the prolongation of certain sounds, usually vowels or semivowels. According to Watkins et al., stuttering is a disorder of "selection, initiation, and execution of motor sequences necessary for fluent speech production". For many people who stutter, repetition is the main concern. The term "stuttering" covers a wide range of severity, from barely perceptible impediments that are largely cosmetic to severe symptoms that effectively prevent oral communication. Almost 70 million people worldwide stutter, about 1% of the world's population. The impact of stuttering on a person's functioning and emotional state can be severe. This may include fears of having to enunciate specific vowels or consonants, fears of being caught stuttering in social situations, self-imposed isolation, anxiety, stress, shame, low self-esteem, being a possible target of bullying (especially in children), having to use word substitution and rearrange words in a sentence to hide stuttering, or a feeling of "loss of control" during speech. Stuttering is sometimes popularly seen as a symptom of anxiety, but there is no direct correlation in that direction. Stuttering is generally not a problem with the physical production of speech sounds or putting thoughts into words. Acute nervousness and stress are not thought to cause stuttering, but they can trigger stuttering in people who have the speech disorder, and living with a stigmatized disability can result in anxiety and high allostatic stress load (chronic nervousness and stress) that reduce the amount of acute stress necessary to trigger stuttering in any given person who stutters, worsening the situation in the manner of a positive feedback system; the name 'stuttered speech syndrome' has been proposed for this condition. Neither acute nor chronic stress, however, itself creates any predisposition to stuttering. The disorder is also variable, which means that in certain situations, such as talking on the telephone or in a large group, the stuttering might be more severe or less, depending on whether or not the person who stutters is self-conscious about their stuttering. People who stutter often find that their stuttering fluctuates and that they have "good" days, "bad" days and "stutter-free" days. The times in which their stuttering fluctuates can be random. Although the exact etiology, or cause, of stuttering is unknown, both genetics and neurophysiology are thought to contribute. There are many treatments and speech therapy techniques available that may help decrease speech disfluency in some people who stutter to the point where an untrained ear cannot identify a problem; however, there is essentially no cure for the disorder at present. The severity of the person's stuttering would correspond to the amount of speech therapy needed to decrease disfluency. For severe stuttering, long-term therapy and hard work is required to decrease disfluency.
  • 4.0K
  • 23 Nov 2022
Topic Review
Self-Amplifying mRNA Vaccine
The core principle behind mRNA vaccines is to encode the antigen in the mRNA and then to deliver the transcript to the host cell cytoplasm using a non-viral delivery system, allowing antigen expression and induction of an antigen-specific immune response. Self-amplifying RNA (saRNA) is a type of mRNA that also encodes viral replicase, which enables the RNA to self-replicate upon delivery into the cell.
  • 4.0K
  • 13 Feb 2021
Topic Review
Point-Of-Care or Point-Of-Need Diagnostic Tests
In the recent years, the progress of international trade and travel has led to an increased risk of emerging infections. Around 75 percent of the pathogens causing these infections are of animal origin. Point-of-care tests (POCT) and point-of-need tests (PONT) have been established in order to directly provide accurate and rapid diagnostics at field level, the patient bed-side or at the site of outbreaks. These assays can help physicians and decision makers to take the right action without delay. Typically, POCT and PONT rely on genomic identification of pathogens or track their immunological fingerprint. Recently, protocols for metagenomic diagnostics in the field have been developed.
  • 4.0K
  • 20 Apr 2021
Topic Review
Religious Trauma Syndrome
Religious trauma syndrome (RTS) is recognized in psychology and psychotherapy as a set of symptoms, ranging in severity, experienced by those who have participated in and left behind authoritarian, dogmatic, and controlling religious groups and belief systems. Symptoms include cognitive, affective, functional, and social/cultural issues as well as developmental delays. RTS occurs in response to two-fold trauma: first the prolonged abuse of indoctrination from a controlling religious community, and secondly the act of leaving the controlling religious community. RTS has developed as its own heuristic collection of symptoms informed by psychological theories of trauma originating in PTSD, C-PTSD and betrayal trauma theory, taking relational and social context into account when approaching further research and treatment. The term religious trauma syndrome was coined in 2011 by psychologist Marlene Winell in an article for British Association for Behavioural and Cognitive Psychotherapies, though the phenomenon was recognized long before that. The term has circulated among psychotherapists, former fundamentalists, and others recovering from religious indoctrination. Winell explains the need for a label and the benefits of naming the symptoms encompassed by RTS as similar to naming anorexia as a disorder: the label can lessen shame and isolation for survivors while promoting diagnosis, treatment, and training for professionals who work with those suffering from the condition. Survivors report relief when they find out that RTS is “real.”
  • 4.0K
  • 22 Nov 2022
Topic Review
Implant–Abutment Connections
Different implant–abutment connections have been developed to reduce mechanical and biological failure. The most frequent complications are loss of preload, screw loosening, abutment or implant fracture, deformations at the different interfaces, and bacterial microleakage.  To review the evidence indicating whether the implant–abutment connection type is significant regarding the following issues: (1) maintenance of the preload in static and dynamic in vitro studies; (2) assessment of possible deformations at the implant–abutment interfaces, after repeated application of the tightening torque; (3) evaluation of the sealing capability of different implant connections against microleakage. 
  • 3.9K
  • 08 Dec 2020
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