3,134 research outputs found
On factoring quartics (mod p)
AbstractWe present a simplified proof of a theorem of Skolem. This result describes the factorization of a fourth degree polynomial (mod p), p an odd prime, in terms of its discriminant and the nature of the roots of a related resolvent cubic polynomial
New Product Theorems for Z-Cyclic Whist Tournaments
AbstractThe aim of this note is to show how existing product constructions for cyclic and 1-rotational block designs can be adapted to provide a highly effective method of obtaining product theorems for whist tournaments
An assessment of high touch object cleaning thoroughness using a fluorescent marker in two Australian hospitals
An Unassigned Group, An Unassigned DepartmentFull Tex
The karabus affair speaks to larger issues for american academic and medical centers.
Finally, on March 12, 2013, a major American newspaper, The Wall Street Journal, reported on the plight of Dr. Cyril Karabus (1,2). Dr. Karabus is the 78 year old pediatric oncologist from Claremont, Capetown, South Africa who is well known as the retired head of the Oncology and Hematology Unit of the Red Cross Children’s Hospital, University of Cape Town, as well as for his devoted service to poor children in the apartheid era. In 2002, he cared for a three-year old Yemeni girl with acute myelogenous leukemia during a locum tenens in the United Arab Emirates (UAE)
Observation of Bernstein Waves Excited by Newborn Interstellar Pickup Ions in the Solar Wind
A recent examination of 1.9 s magnetic field data recorded by the Voyager 2 spacecraft in transit to Jupiter revealed several instances of strongly aliased spectra suggestive of unresolved high-frequency magnetic fluctuations at 4.4 AU. A closer examination of these intervals using the highest resolution data available revealed one clear instance of wave activity at spacecraft frame frequencies from 0.2 to 1 Hz. Using various analysis techniques, we have characterized these fluctuations as Bernstein mode waves excited by newborn interstellar pickup ions. We can find no other interpretation or source consistent with the observations, but this interpretation is not without questions. In this paper, we report a detailed analysis of the waves, including their frequency and polarization, that supports our interpretation
Impacts of Climate Change on indirect human exposure to pathogens and chemicals from agriculture
Objective: Climate change is likely to affect the nature of pathogens and chemicals in the environment and their fate and transport. Future risks of pathogens and chemicals could therefore be very different from those of today. In this review, we assess the implications of climate change for changes in human exposures to pathogens and chemicals in agricultural systems in the United Kingdom and discuss the subsequent effects on health impacts.
Data sources: In this review, we used expert input and considered literature on climate change ; health effects resulting from exposure to pathogens and chemicals arising from agriculture ; inputs of chemicals and pathogens to agricultural systems ; and human exposure pathways for pathogens and chemicals in agricultural systems.
Data synthesis: We established the current evidence base for health effects of chemicals and pathogens in the agricultural environment ; determined the potential implications of climate change on chemical and pathogen inputs in agricultural systems ; and explored the effects of climate change on environmental transport and fate of different contaminant types. We combined these data to assess the implications of climate change in terms of indirect human exposure to pathogens and chemicals in agricultural systems. We then developed recommendations on future research and policy changes to manage any adverse increases in risks.
Conclusions: Overall, climate change is likely to increase human exposures to agricultural contaminants. The magnitude of the increases will be highly dependent on the contaminant type. Risks from many pathogens and particulate and particle-associated contaminants could increase significantly. These increases in exposure can, however, be managed for the most part through targeted research and policy changes
Lactic Acid Bacteria: Review on the Potential Delivery System as an Effective Probiotic
Lactic acid bacteria are gram-positive microorganisms that are characterized by the production of lactic acid as a key fermentation product. LAB, specifically Lactobacillus delbrueckii subsp. bulgaricus, are essential dairy starter cultures for the manufacture of several fermented dairy products such as yogurt. Some LAB are useful microorganisms and are well known to have probiotic effects to provide foods with unique sensory qualities such as aroma and taste. Probiotic strains help to strengthen the human immune system, increasing the body’s resistance to diseases. Additionally, probiotics and postbiotics improve gut microbiome balance and prevent health issues. Postbiotics are substances that are produced by microbes’ metabolic activities and have a positive impact on diseases, either directly or indirectly. Extensive research has shown that postbiotics possess immunomodulatory and significant clinical effects. Their use has been found to enhance general health and alleviate symptoms of various disorders in healthy individuals. Furthermore, postbiotics exhibit anti-inflammatory, antioxidant, and anticancer properties. Therefore, this chapter presents an overview and the importance of LAB as a probiotic and its importance to human health, metabolic fermentation, and antioxidant potential. The review also discusses different biotechnological methods that improve the survival rate of probiotics during processing and GIT transit like microbial encapsulation
Archeological Testing and Data Recovery at 41ZV202, Zavala County, Texas
At the request of the Texas Department of Transportation, Environmental Affairs Division (TxDOT-ENV), the Center for Archaeological Research (CAR) of The University of Texas at San Antonio (UTSA) conducted archeological significance testing at 41ZV202, a prehistoric site located in northwestern Zavala County, in March of 2003. The work, conducted under Texas Antiquities Permit No. 3071 issued to Dr. Steven A. Tomka, was done in anticipation of the potential widening by TxDOT of FM 481. While materials dating to the Archaic were also present, the testing demonstrated the presence of significant Late Prehistoric (Austin Interval) deposits with good integrity within a portion of the TxDOT right-of-way (ROW). As TxDOT construction could not avoid these deposits, and as both the Texas Historical Commission (THC) and TxDOT concurred with CAR’s recommendations that the deposits were eligible for listing on the National Register of Historic Places (NRHP) under criterion d of 36CFR 60.4, data recovery investigations were initiated. CAR began that work in July and August of 2003. The testing permit was amended to include the data recovery efforts. Dr. Russell Greaves served as project archeologist for both the testing and data recovery effort at 41ZV202.
The testing and data recovery work consisted of the excavation of a 53-m-long Gradall trench, exposing and profiling a 75-m-long road cut, and the hand excavation of 52 1 x 1 meter units that removed approximately 34.6 m3 of soil. Testing identified two large, dark stained areas designated Features 4 and 5, an associated hearth (Feature 7), and a small cluster of FCR (Feature 6). Just over 1,000 chipped stone items were recovered, including several Scallorn points, one reworked dart point, several bifaces, and two flake tools. Eleven AMS radiocarbon dates were submitted from deposits, with eight clustering around 1000 BP. Data recovery efforts defined FCR features 8 through 13. In addition, 24 arrow points, several dart points, a variety of unifacial and bifacial tools, a small number of cores, roughly 6,000 pieces of debitage, and a variety of burned sandstone, were recovered. We also collected small quantities of bone and mussel shell along with about 14,350 gastropod shells, and a variety of soil samples. Finally, all calcium carbonate nodules were retained from the screens.
Following the completion of data recovery efforts, the CAR was directed by TxDOT to develop a research design for the analysis of the material from 41ZV202. TxDOT and THC accepted that research design in November of 2004, at which time the CAR began analysis and report production. Unfortunately, by 2005 project archeologist Russell Greaves had left the CAR. At that point, CAR assistant director Dr. Raymond Mauldin took over the project. The analysis of the 41ZV202 Late Prehistoric data outlined in this report is conducted in the context of a large-scale, theoretically driven model of adaptation for hunters and gatherers loosely based on aspects of Optimal Foraging Theory. In addition to 41ZV202, the approach relies on comparative data sets from Late Archaic and other Late Prehistoric sites from South and South-Central Texas to investigate shifts in subsistence, technology, and mobility across this broad region.
At this time, discard decisions have not been made. However, all artifacts and associated samples collected and retained during this project, along with all project-associated documentation, are to be permanently curated at the CAR according to Texas Historical Commission guidelines
Human Immune System Development and Rejection of Human Islet Allografts in Spontaneously Diabetic NOD-Rag1null IL2rγnull Ins2Akita Mice
OBJECTIVE: To create an immunodeficient mouse model that spontaneously develops hyperglycemia to serve as a diabetic host for human islets and stem cell-derived beta-cells in the absence or presence of a functional human immune system.
RESEARCH DESIGN AND METHODS: We backcrossed the Ins2(Akita) mutation onto the NOD-Rag1(null) IL2rgamma(null) strain and determined 1) the spontaneous development of hyperglycemia, 2) the ability of human islets, mouse islets, and dissociated mouse islet cells to restore euglycemia, 3) the generation of a human immune system following engraftment of human hematopoietic stem cells, and 4) the ability of the humanized mice to reject human islet allografts.
RESULTS: We confirmed the defects in innate and adaptive immunity and the spontaneous development of hyperglycemia conferred by the IL2rgamma(null), Rag1(null), and Ins2(Akita) genes in NOD-Rag1(null) IL2rgamma(null) Ins2(Akita) (NRG-Akita) mice. Mouse and human islets restored NRG-Akita mice to normoglycemia. Insulin-positive cells in dissociated mouse islets, required to restore euglycemia in chemically diabetic NOD-scid IL2rgamma(null) and spontaneously diabetic NRG-Akita mice, were quantified following transplantation via the intrapancreatic and subrenal routes. Engraftment of human hematopoietic stem cells in newborn NRG-Akita and NRG mice resulted in equivalent human immune system development in a normoglycemic or chronically hyperglycemic environment, with \u3e50% of engrafted NRG-Akita mice capable of rejecting human islet allografts.
CONCLUSIONS: NRG-Akita mice provide a model system for validation of the function of human islets and human adult stem cell, embryonic stem cell, or induced pluripotent stem cell-derived beta-cells in the absence or presence of an alloreactive human immune system
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