Both a potent marine biotoxin and neurotoxin, saxitoxin (STX) is considered the active chemical responsible for deaths associated with the disease known as Paralytic Shellfish Poisoning (PSP). STX manifests as a Harmful Algal Bloom (HAB) due to significant algal cell proliferation in aquatic environments. Although its original detection was in 1957, the chemical currently lacks a detoxification pathway and detailed mechanism of action. Moreover, prediction and detection of STX is not fully understood, and frequency of saxitoxin blooms is on the rise. The physical and economic impact of saxitoxin on human and aquatic life continues to increase worldwide, stimulating a renewed interest and research into this chemical.
Psychological testing has been used in several industries since the 19th century. At this time, over 100,000 tests are being produced annually with no signs of slowing down. The Armed Services Vocation Aptitude Battery, or ASVAB, was produced by and promptly distributed by the Department of Defense (DOD) to promote career exploration. Currently, over one million men and women each year take this test to determine their career choice. The ASVAB is designed using the Item Response Theory (IRT) and can be taken by pencil and paper or on the computer. Scoring is calculated using a standard and weighted score. Research shows this examination to be highly reliable and valid, after previous errors had been corrected. Many recruiters say the ASVAB is a crucial tool for recruitment and would lose over half of their recruits if it was ever discontinued. Weaknesses of the exam include lack of parental consent, possible self-doubt, and elimination of postsecondary attendance. Further studies are needed to determine the exact negative repercussions. Errors notwithstanding, the ASVAB is a solid examination with proven successful track record. Future endeavors in this exam should only address the two issues previously stated.
Human immunodeficiency virus type 1 (HIV-1) has been shown to involve numerous cellular factors to aid in successful viral propagation. One of these host factors is Tat-specific factor 1 (Tat-SF1). This human protein contains two RNA recognition motifs, and serves as a transcription-splicing factor. During post-transcriptional modification of HIV-1 RNA, the primary viral transcript is spliced to produce three major size classes of mRNAs: singly spliced, fully spliced, and unspliced. The relative levels of each of these viral RNA size classes are important, as they can regulate the resulting levels of viral proteins and viral infectivity. To further investigate Tat-SF1’s role as a host factor for HIV-1, the levels of different HIV-1 RNA size classes were studied in human HeLa cells with overexpressed levels of Tat-SF1. Reverse transcription and real-time PCR were then used to quantify HIV-1 RNA levels. Comparative data analysis revealed a decrease in each HIV-1 RNA size class level with Tat-SF1 overexpression, with a dramatic decrease in the levels of singly spliced mRNAs. These results support the notion that Tat-SF1 does indeed plays a role in modulating HIV-1 RNA levels in human cells.
The World Health Organization deﬁnes stroke as ‘rapidly developing clinical signs of focal (or global) disturbance of cerebral function, with symptoms lasting 24 h or longer or leading to death, with no apparent cause other than that of vascular origin’(Armstead et al. 2010). Current therapies for ischemic strokes, while effective, have significant hemorrhagic risks to the patient and must be administered within a very narrow timeframe (Frendl et al. 2011; Alexandrov 2010). Therefore, there is a need to investigate novel therapeutic agents as well as improve drug administration techniques to acutely decrease the injury caused to the brain in the event of a stroke, while minimizing the potential for hemorrhages and reperfusion injuries.
Netgear® WGT634U 108-megabyte-per-second wireless storage routers mounted within environmental enclosures at outdoor and indoor locations across the Cambridge coverage area serve as signal repeater nodes for the network. Denton, Texas, is a promising site to deploy a wireless network similar to the one in Cambridge. However, the ambient outdoor conditions in Denton differ from those in Cambridge and may exceed the operating envelope of the repeater nodes if not mitigated by well-designed environmental enclosures. By instrumenting asample signal repeater with thermocouples and baking it in a furnace, we determined that the node’s built-in safety shut-off temperature is 130 ± 3 °C and that the temperature at which irreversible damage occurs is in the range of 135 °C to 145 °C.
Aging affects immune function, increasing an organism’s vulnerability to infectious and neoplastic diseases, however efforts in medical research have focused on adaptive immunity, leaving the role of innate immunity largely open for investigation. Echinoderms are an excellent model for studying innate immunity as invertebrates lacking adaptive immunity and as deuterosomes being more closely related to humans than any other invertebrate group. A survey of the immune gene repertoire encoded by the sea urchin genome reveals enormous and unprecedented complexity and it has been hypothesized that the robust innate immune system may play a role in both the longevity and resistance to disease that these animals exhibit.
It has been shown that inhaled particulate matter such as air pollution and asbestos are linked to a number of immune diseases such as asthma, and Systemic Lupus Erythematosus (SLE), respectively. This research may contribute to understanding the mechanisms of how asbestos and air pollution particulate (PM10) produce oxidative stress on macrophages, as well as how the macrophages will respond to the oxidative stressors. Using Flow Cytometry, DCFDA Fluorescence, Glutamate Transport, and Cytokine Bead Array assays, we have shown that exposure to asbestos and PM10 up-regulates system xc- in macrophages, which reduces oxidative stress for the macrophage by providing substrates for antioxidants. The results demonstrate that asbestos, but not PM10, induces both expression and activity of system xc-.
Microgreens are seven- to ten-day-old seedlings of various vegetable crops that are packaged as young shoots, including both cotyledons and hypocotyls. To improve the marketability of this highly perishable product, shelf life must be extended by controlling respiration rates. Little information is available describing the post-harvest characteristics of this high value specialty crop, and its respiration rates have not yet been carefully quantified. The present study aims to investigate the respiration rates and shelf life of microgreens.
Education relies on the ability to continually learn and has often been considered a social science rather than a physical science. Advances in neuroscience now allow us to approach learning and intelligence from a scientific standpoint. There is a persistent problem of unequal access to quality education as well as broad social issues that stem from not having a solid education to grow from. In order to provide a conceptually solid attempt to the solution, I work to apply our understanding of cognitive science to this social issue.
Hermit crab populations are limited by shell availability; therefore fights to gain a suitable shell are frequent. Although a large amount of research has studied hermit crab aggressive behavior, few have correlated this behavior with location. This study was carried out to investigate the influence of wave exposure on the behavior of the common hermit crab Pagarus bernhardus. Crabs from two sites on Isle of Cumbrae, with differing levels of wave exposure, were tested for their aggressive behavior in laboratory trails.
Due to the fear of Islam post 9/11, Muslim women, in particular, have been dehumanized and portrayed in the media as haunting and as a result have experienced symptoms of PTSD. This article seeks to explain the cause of such public disdain for Muslim women. This case study examines an MSNBC, CNN, and FOX news story in which Muslim women travelled to the amusement park “Rye Playland” in Rye, New York to celebrate a religious holiday but were banned from the rides when administrators cited the Islamic headgear to be a choking hazard.
Are all students equally likely to utilize websites like RateMyProfessor to determine the appropriate courses to take in college? Positive and negative professor reviews were examined to discover whether previous student feedback might influence future students’ perceptions of instructor attractiveness and anticipated academic effort. Two hypothetical professors, Professor X and A were created for this study. Each professor had either positive or negative commentary. Two hypotheses were formulated: (1) there would be a main effect between the low self-esteem individuals and the likelihood of choosing Professor X, with positive student commentary; and (2) students that are attracted to a professor review will anticipate more positive academic effort for the course
The growth in antibiotic resistance has resulted in a constant need for novel antimicrobials. To slow down the acquisition of resistance many pharmaceutical companies are now focusing on the development of novel, narrow-spectrum therapeutics with specificity, potency and decreased side effects. Antibiotic production is a feature of several soil microbes and may represent a survival mechanism whereby organisms can eliminate competition and colonize a niche. Since many of the original antibiotics were harvested from tropical soil Actinomycete species, we collected soil samples from Jamaica as the island’s soil microbiology is rich and poorly understood.
Previous studies exploring the potential of developing mangrove oyster fisheries in Ghana have suggested that this approach could provide both financial gain (Obodai and Yankson, 1999a) and nutritional value (Yankson 2004) to the Ghanaian people, supplementing a historically low-protein diet as well as augmenting local economies. However ,information on the basic ecology of the West African mangrove oyster (Crassostrea tulipa) is limited. This study aimed to build preliminary knowledge of this species by investigating the precise relationship between environmental salinity and filtration rates
Lateral Sclerosis (ALS) and Spinal Muscular Atrophy (SMA) are two poorly understood Motor neuron diseases. Both diseases eventually prove fatal and their complex pathogenesis makes them difficult to treat. We reviewed the current literature to produce a comprehensive but succinct guide to ALS and SMA for the undergraduate. We review the genetics, aetiology and pathogenesis to identify similarities and differences between the two diseases.
Numerous studies of forest fragmentation have found a negative relationship between density of Peromyscus leucopus and forest fragment size. This relationship may be caused by both more food, and more cover from predation in smaller fragments, which have more structurally complex understory vegetation than larger fragments. However, we do not know the extent to which the proximity of understory vegetation affects selection of nesting sites within fragments. We hypothesized that nest boxes in highly vegetated areas would be utilized more often by P. leucopus than nest boxes in sparsely vegetated areas.
High-stake decisions are based on neuropsychological test data, such as diagnosis of specific learning disabilities and mental retardation. Thus, it is crucial to understand how anxiety and stress affect test scores on the most popular and current IQ measure, Wechsler Adult Intelligence Scale – Fourth Edition (WAIS-IV). Previous studies have shown negative effects of self-reported anxiety on performance on various cognitive tasks; however, these studies either used a single measure of anxiety or tested a limited number of subtests from previous versions of the WAIS. The current study sought to examine the relationship of anxiety (as determined by self-report data), stress (as determined by physiological data), and performance on the WAIS-IV.
The most frequently used heat engines for transformation of heat into useful mechanical work are internal and external combustion engines. These engines work with high combustion temperatures and large temperature differences are necessary to achieve high efficiency. Harmful byproducts result from the combustion processes. In order to solve the environmental problem during the transformation of heat into mechanical work, new alternative fuels, alternative drives and new technologies are being investigated. This paper hypothesizes that it is possible to transform heat into work at low temperatures and at low temperature differences with less environmental pollution.