cssi/SciSciGPT-SciSciNet huggingface dataset:
Advances in the diagnosis and surveillance of Barrett’s esophagus (with videos)

Background and Aims Most patients diagnosed with esophageal adenocarcinoma do not carry a known diagnosis of Barrett's esophagus (BE), suggesting that an improved approach to screening may potentially be of benefit. The use of dysplasia as a biomarker and random biopsy protocols for its detection has limitations. In addition, detecting and appropriately classifying dysplasia in patients with known BE can be difficult. Methods This document reviews several technologies with a recently established or potential role in the diagnosis and/or surveillance of BE as well as risk stratification for progression to esophageal adenocarcinoma. Results Two technologies were reviewed for imaging or tissue sampling: (1) wide-area transepithelial sampling and (2) volumetric laser endomicroscopy. Four technologies were reviewed for molecular and biomarker technologies for diagnosis and risk stratification: (1) Cytosponge, (2) mutational load, (3) fluorescence in situ hybridization, and (4) immunohistochemistry. Conclusion Several technologies discussed in this document may improve dysplasia detection in BE in a wide-field manner. Moreover, the addition of different biomarkers may aid in enhanced risk stratification to optimize approaches to surveillance or treatment for patients with BE.
Field assessment of interreplicate variability from eight electromagnetic soil moisture sensors

Abstract Interreplicate variability—the spread in output values among units of the same sensor subjected to essentially the same condition—can be a major source of uncertainty in sensor data. To investigate the interreplicate variability among eight electromagnetic soil moisture sensors through a field study, eight units of TDR315, CS616, CS655, HydraProbe2, EC5, 5TE, and Teros12 were installed at a depth of 0.30 m within 3 m of each other, whereas three units of AquaSpy Vector Probe were installed within 3 m of each other. The magnitude of interreplicate variability in volumetric water content (θv) was generally similar between a static period near field capacity and a dynamic period of 85 consecutive days in the growing season. However, a wider range of variability was observed during the dynamic period primarily because interreplicate variability in θv increased sharply whenever infiltrated rainfall reached the sensor depth. Interreplicate variability for most sensors was thus smaller if comparing θv changes over several days that excluded this phenomenon than if comparing θv directly. Among the sensors that also reported temperature and/or apparent electrical conductivity, the sensors exhibiting the largest interreplicate variability in these outputs were characterized by units with consistently above or below average readings. Although manufacturers may continue to improve the technology in and the quality control of soil moisture sensors, users would still benefit from paying greater attention to interreplicate variability and adopting strategies to mitigate the consequences of interreplicate variability.
Assessing Insulin and Glucose Tolerance in the Aging Mouse

Basic preclinical research on the pathophysiology of aging-related and/or metabolic diseases, including type 2 diabetes, largely relies on animal models. Mice, the most commonly used species to study the biological processes that regulate aging and its associated functional decline, have helped researchers to identify pathways, mechanisms, and genes that regulate aging-related diseases and aging itself and thus are intervention targets. Changes in energy metabolism are a central component of the biological processes that undergo significant alterations with age. For example, the prevalence of type 2 diabetes and impaired glucose tolerance increases with aging. Not surprisingly, the characterization of these changes for metabolic phenotyping is commonly found in laboratories around the world. Glucose tolerance tests (GTT) and insulin tolerance tests (ITT) do not require surgery, are relatively easy to perform, and, most importantly, are minimally invasive and are thus the preferred method to evaluate glucose homeostasis in the aging animal. Both assays measure blood glucose following the bolus injection of either glucose (for GTT) or insulin (for ITT). Although they are standard procedures, the interpretation of both assays is strongly influenced by laboratory practices and variable experimental conditions. Here, we aim to provide simple guidelines that can be useful to standardize GTT and ITT in the aging mouse.
Spectral Prediction and Notching of RF Emitters for Cognitive Radar Coexistence

The increasing demand for radio frequency (RF) spectrum requires radars to coexist with interfering RF emitters. Innovations in waveform design paired with dynamic spectrum access techniques allow for efficient spectrum sharing for radar. This work evaluates a recently developed real-time implementation of spectrum sharing cognitive radar using commercial-of-the-shelf (COTS) hardware. Prediction of coexisting RF emitter frequencies informs the design of spectrally notched FM noise waveforms on transmit. Waveform notches are optimized on a pulse-to-pulse basis while accounting for the zero-order hold model inherent to lower fidelity digital-to-analog converters to ensure desired reconstruction. The radar system employs cognition to learn and predict RF emitter activity via a stochastic model-based approach. Initially, passive spectrum observations are used to estimate a stochastic model which is then exploited to predict the likelihood of future RF activity. The benefits and limitations of this sense-predict-and-notch (SPAN) approach are evaluated using a set of synthetic interference scenarios in real-time.
Food insecurity among graduate students: prevalence and association with depression, anxiety and stress.

Objective: The impact of food insecurity on mental health has not yet been examined in graduate students, a population widely considered at elevated risk for financial strain and negative mental health outcomes. This study aimed to derive initial prevalence estimates of food insecurity in a sample of current graduate students at a large state university and to elucidate the relationship between food insecurity and depression, anxiety and stress in this sample. Design: Cross-sectional online survey including the US Household Food Security Survey Module: Six-Item Short Form and the Depression, Anxiety, and Stress Scales (DASS-21). Setting: University in the northeastern region of the USA. Participants: Two hundred sixty-three graduate students. Results: In the present sample, 59·7 % of participants reported high/marginal food security, 18·5 % reported low food security and 21·8 % reported very low food security. Graduate students with very low food security reported significantly greater depression (η 2 = 0·09), anxiety (η 2 = 0·10) and stress (η 2 = 0·10), compared with those with low food security and high food security (all P’s < 0·001). Conclusions: Food insecurity occurred in nearly half of the graduate students surveyed, and very low food security was associated with elevated levels of depression, anxiety and stress. Findings highlight the need to address food insecurity and associated elevated mental health problems present among graduate students.
Evaluation of pyrrolizidine alkaloid-induced genotoxicity using metabolically competent TK6 cell lines.

Abstract Pyrrolizidine alkaloid (PA)-containing plants are among the most common poisonous plants affecting humans, livestock, and wildlife worldwide. A large number of PAs are known to induce genetic damage after metabolic activation. In the present study, using a battery of fourteen newly developed TK6 cell lines, each expressing a single human cytochrome P450 (CYP1A1, 1A2, 1B1, 2A6, 2B6, 2C8, 2C18, 2C9, 2C19, 2D6, 2E1, 3A4, 3A5, and 3A7), we identified specific CYPs responsible for bioactivating three PAs – lasiocarpine, riddelliine, and senkirkine. Among the fourteen cell lines, cells expressing CYP3A4 showed significant increases in PA-induced cytotoxicity, evidenced by decreased ATP production and cell viability, and increased caspase 3/7 activities. LC-MS/MS analysis revealed the formation of 1-hydroxymethyl-7-hydroxy-6,7-dihydropyrrolizine (DHP), the main reactive metabolite of PAs, in CYP3A4-expressing TK6 cells. DHP was also detected in CYP3A5- and 3A7-expressing cells after PA exposure, but to a much lesser extent. Subsequently, using a high-throughput micronucleus assay, we demonstrated that PAs induced concentration-dependent increases in micronuclei and G2/M phase cell cycle arrest in three CYP3A variant-expressing TK6 cell lines. Using Western blotting, we observed that PA-induced apoptosis, cell cycle changes, and DNA damage were primarily mediated by CYP3A4. Benchmark dose (BMD) modeling demonstrated that lasiocarpine, of the three PAs, was the most potent inducer of micronuclei, with a BMD100 of 0.036 μM. These results indicate that our TK6 cell system holds promise for genotoxicity screening of compounds requiring metabolic activation, identifying specific CYPs involved in bioactivation, and discriminating the genotoxic compounds that have different chemical structures.
Spatiotemporal changes in vegetation greenness across continental Ecuador: a Pacific-Andean-Amazonian gradient, 1982–2010

The tropics are greening, but little is known about greening patterns in the tropical Andes. Using Normalized Difference Vegetation Index (NDVI) data on monthly and annual bases, this research anal...
Family Composition and the Benefits of Participating in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC)

WIC is designed to promote the health and nutrient consumption of pregnant (or postpartum) women, infants, and young children. Food, however, is often a communal commodity shared by all household members; thus, a family’s composition may impact the health benefits received by a WIC participant. Using data from the 2010 wave of the National Health Interview Survey, this study finds that an only child who participates in WIC receives a health benefit from their participation while the benefits received by children with siblings are dependent on the age, gender, and number of siblings with whom they share a residence.
Incorporation of unnatural amino acid for the tagging of cannabinoid receptors 1 and 2 reveals receptor roles in regulating cAMP levels

Abstract The role of CB1/CB2 co-expression in cell signaling remains elusive. We established a simplified mammalian cell model system in which expression of CB1 or CB2 can be easily monitored under a confocal microscope. For this, we applied amber codon suppression in live cells to incorporate a single trans-cyclooctene (TCO) bearing amino acid in one of the extracellular loops of CB1 or CB2, followed by fluorescent labeling via click chemistry. We employed genetically encoded biosensors to measure the roles of CB1 and/or CB2 in regulating intracellular calcium ([Ca2+]i) and cAMP ([cAMP]i) levels. We show that the agonist-mediated activation of tagged-CB1 or -CB2 can transiently elevate [Ca2+]i levels. However, when the two receptors were co-expressed in the same cell, CB2 no longer signaled through calcium although CB1-mediated transient elevation of [Ca2+]i levels was unaffected. Because of the existence of crosstalk between calcium and cAMP signaling, we measured the effects of CB1 and/or CB2 in regulating adenylate cyclase activity. We found that the expression of CB1 increased forskolin-induced [cAMP]i levels compared to non-transfected cells. Conversely, CB2 expression decreased stimulated [cAMP]i levels under the same conditions. Finally, co-expressed CB1 and CB2 receptors showed additive yet opposing effects on stimulated [cAMP]i levels. These observations suggest that co-expressed CB1/CB2 act locally as a pair in regulating cell excitability by modulating stimulated [cAMP]i levels.
Mixed infection, risk projection, and misdirection: Interactions among pathogens alter links between host resources and disease

A growing body of literature links resources of hosts to their risk of infectious disease. Yet most hosts encounter multiple pathogens, and projections of disease risk based on resource availability could be fundamentally wrong if they do not account for interactions among pathogens within hosts. Here, we measured infection risk of grass hosts (Avena sativa) exposed to three naturally co‐occurring viruses either singly or jointly (barley and cereal yellow dwarf viruses [B/CYDVs]: CYDV‐RPV, BYDV‐PAV, and BYDV‐SGV) along experimental gradients of nitrogen and phosphorus supply. We asked whether disease risk (i.e., infection prevalence) differed in single versus co‐inoculations, and whether these differences varied with rates and ratios of nitrogen and phosphorus supply. In single inoculations, the viruses did not respond strongly to nitrogen or phosphorus. However, in co‐inoculations, we detected illustrative cases of 1) resource‐dependent antagonism (lower prevalence of RPV with increasing N; possibly due to competition), 2) resource‐dependent facilitation (higher prevalence of SGV with decreasing N:P; possibly due to immunosuppression), and 3) weak or no interactions within hosts (for PAV). Together, these within‐host interactions created emergent patterns for co‐inoculated hosts, with both infection prevalence and viral richness increasing with the combination of low nitrogen and high phosphorus supply. We demonstrate that knowledge of multiple pathogens is essential for predicting disease risk from host resources and that projections of risk that fail to acknowledge resource‐dependent interactions within hosts could be qualitatively wrong. Expansions of theory from community ecology theory may help anticipate such relationships by linking host resources to diverse pathogen communities.
A 32A 5V-Input, 94.2% Peak Efficiency High-Frequency Power Converter Module Featuring Package-Integrated Low-Voltage GaN NMOS Power Transistors

A 5V-input, high-frequency, high-density (9A/mm2) buck converter featuring a low-voltage GaN power transistor (with 5-10× better FoM than Si) with on-die gate clamps, integrated with a CMOS companion die in 4mm × 4mm package, achieves 94.2% peak efficiency for 5V in /1V out at 3MHz switching frequency with a 40nH inductor.
Engaging Pre-Service and In-Service Teachers in Online Mathematics Teaching and Learning: Problems and Possibilities

Many pre-service and in-service mathematics teachers have reflected vulnerabilities and unpreparedness for online teaching during the period of the COVID-19 pandemic. They searched for supports and resources to enhance their knowledge, skills, and dispositions relative to online teaching and learning. However, there is no clear path towards reaching these goals. This qualitative and interpretive research focuses on 48 pre-service and in-service teachers’ online teaching and learning experiences; while they were engaged in a semester-long mathematics-method course. The findings of this study suggest that factors, like interactions, communication, and peer support impact the pre-service and the in-service mathematics teachers’ beliefs and practices toward online teaching and learning. The findings also suggest that social and cultural factors, such as knowing and understanding students’ cultural background, access and equity in mathematics education, learners’ social and emotional development, and parents’ involvement influence mathematics teachers’ practices regarding online teaching and learning. The findings indicate that the transformation from in-person to online learning requires the enhancement of pre-service and in-service mathematics teachers’ online preparations, particularly in the areas of technology, pedagogy, communication skills, and classroom management. https://doi.org/10.26803/ijlter.20.11.6
How Should We Feel About Our Own Death

Sigmund Freud argued that people believe in God because they fear their own death. If there is a divine entity that takes a very positive personal interest in you, and has the power to keep your personality alive after your body has died, then death need not concern you because you will never undergo it. Hence, since death is unable to harm those God preserves, then fear and other feelings and emotions should alter accordingly. Fear, for instance, should be assuaged by the belief in this god, although in reality it might be simply repressed. In this chapter, I examine the morality of some of the most significant feelings and emotions we have toward our own deaths. Depending upon which view is adopted for understanding emotions and feelings—and I advocate for a pluralistic, pragmatic approach—we can not only have morally right/bad or wrong/bad emotional reactions and emotions, we can also have obligations to feel a certain way at a certain time.
Gastrointestinal Manometry: Tales of the Intrepid Transducer

An understanding of basic physiological principles allows the clinician to analyze and address patient problems. In this chapter, we will present cases and ask you to evaluate them. Feel free to discuss the questions with your classmates/colleagues or to utilize other sources to answer the questions. The key objectives include (1) describing the role of esophageal manometry for evaluating refractory GERD patients, (2) defining achalasia and delineating the role of esophageal manometry in making a diagnosis, (3) examining the importance of diffuse esophageal spasm as a cause of noncardiac chest pain and the role of esophageal manometry in management, (4) defining Hirschsprung’s disease and delineating the role of anorectal manometry in making the diagnosis, and (5) describing the role of anorectal manometry in the evaluation and management of fecal incontinence.
Experimental hyperglycemic states not primarily due to a lack of insulin.

Publisher Summary A variable number of abnormalities combine to make up the syndrome known as “diabetes mellitus.” The definition of exactly what constitutes the diabetic state is somewhat arbitrary and semantic, and is often viewed differently by the experimentalist and the clinician. Hyperglycemia is the one condition common to all definitions of diabetes. The most common clinical type of diabetes mellitus and the diabetic states, which have been most thoroughly investigated experimentally, are caused by a primary lack or absence of insulin. It is perhaps a useful coincidence that in English the word diabetes is spelled like a plural. Certainly it ought to be considered as a collective noun, representing a class of very different conditions presenting the common characteristic of high blood glucose levels. Even in this regard, differences exist between hyperglycemias as regards their degree and their dependence upon the nature and the amount of the diet concerned. The chapter describes those diabetic states occurring clinically and produced experimentally which are not due primarily to a lack of insulin. Some of these hyperglycemic states may subsequently depend upon a lack of insulin for their persistence, but their geneses depend upon other factors.
A Photochemically Active Particle Derived from Chloroplasts by the Action of the Detergent Triton X-100

Abstract Treatment of spinach chloroplasts with 4% Triton X-100 yields fragments which are separable by centrifugation. In the medium used (which is 4% in Triton X-100 and 0.5 m in sucrose) for the initial incubation particles sedimented by centrifugation at 144,000 x g for 1, 3, and 8 hours are relatively inactive in the partial photoreactions representative of photosynthesis. These particles contain an increased amount of chlorophyll b when compared with chloroplasts. These particles could represent Pigment System 2 which is involved in oxygen evolution in the intact chloroplast but is inactivated by the detergent treatment. The supernatant fluid from the centrifugation described above contains particles which are sedimented by 10 hours of centrifugation at 144,000 x g after diluting with an equal volume of water. These particles exhibit a high rate of nicotinamide adenine dinucleotide phosphate photoreduction, with rates as high as 1980 µmoles of NADP photoreduced per hr per mg of chlorophyll observed. This reaction requires the presence of spinach ferredoxin, ferredoxin-NADP reductase, and plastocyanin in addition to an electron donor system of ascorbate-2,6-dichloroindophenol (ascorbate alone is only moderately active) or ascorbate-N,N,N',N'-tetramethyl-p-phenylenediamine. This activity is heat-labile, being destroyed by heating to 40° for 5 min. Other photochemical reactions supported by this particle include methyl red reduction (supported by ascorbate-dichloroindophenol), ferrocytochrome c photooxidation (aerobic), and ferricytochrome c photoreduction (supported by reduced trimethylbenzoquinone). Methyl red photoreduction activity is also destroyed by heating, while ferricytochrome c photoreduction activity is only partially destroyed by heating to 70°. Methyl red photoreduction and ferrocytochrome c photooxidation also are stimulated by plastocyanin. The photoactive particles contain low amounts of chlorophyll b, show an unresolved cytochrome spectrum indicating the presence of cytochrome f and b6, exhibit an increased absorbance at 700 mµ, and show a greatly enhanced P700 absorption change and electron spin resonance spectrum upon illumination. The particle is only weakly fluorescent and does not emit any delayed light following illumination. All these properties indicate that this particle retains the photoactive Pigment System 1 which is responsible for NADP photoreduction in photosynthesis.
Studies in biomimetic alkaloid syntheses—10: The synthesis of a 19-oxosecodine and its cyclization to minovincine

Abstract The synthesis, isolation and characterization of 19-oxo Δ 20,21 secodine ( 2 ) is described. This compound is the first example of a stabilized, potentially reactive secodine intermediate in alkaloid synthesis. It cyclized to minovincine (1) in 77% yield in refluxing m -xylene.
Rho GTPases and Regulation of Hematopoietic Stem Cell Localization

Bone marrow engraftment in the context of hematopoietic stem cell and progenitor (HSC/P) transplantation is based on the ability of intravenously administered cells to lodge in the medullary cavity and be retained in the appropriate marrow space, a process referred to as homing. It is likely that homing is a multistep process, encompassing a sequence of highly regulated events that mimic the migration of leukocytes to inflammatory sites. In leukocyte biology, this process includes an initial phase of tethering and rolling of cells to the endothelium via E- and P-selectins, firm adhesion to the vessel wall via integrins that appear to be activated in an "inside-out" fashion, transendothelial migration, and chemotaxis through the extracellular matrix (ECM) to the inflammatory nidus. For HSC/P, the cells appear to migrate to the endosteal space of the bone marrow. A second phase of engraftment involves the subsequent interaction of specific HSC/P surface receptors, such as alpha(4)beta(1) integrin receptors with vascular cell-cell adhesion molecule-1 and fibronectin in the ECM, and interactions with growth factors that are soluble, membrane, or matrix bound. We have utilized knockout and conditional knockout mouse lines generated by gene targeting to study the role of Rac1 and Rac2 in blood cell development and function. We have determined that Rac is activated via stimulation of CXCR4 by SDF-1, by adhesion via beta(1) integrins, and via stimulation of c-kit by the stem cell factor-all of which involved in stem cell engraftment. Thus Rac proteins are key molecular switches of HSC/P engraftment and marrow retention. We have defined Rac proteins as key regulators of HSC/P cell function and delineated key unique and overlapping functions of these two highly related GTPases in a variety of primary hematopoietic cell lineages in vitro and in vivo. Further, we have begun to define the mechanisms by which each GTPase leads to specific functions in these cells. These studies have led to important new understanding of stem cell bone marrow retention and trafficking in the peripheral circulation and to the development of a novel small molecule inhibitor that can modulate stem cell functions, including adhesion, mobilization, and proliferation. This chapter describes the biochemical footprint of stem cell engraftment and marrow retention related to Rho GTPases. In addition, it reviews abnormalities of Rho GTPases implicated in human immunohematopoietic diseases and in leukemia/lymphoma.
Propulsion Simulation Test Technique for V/STOL Configurations

Ames Research Center is developing the technology for turbine-powered jet engine simulators so that airframe/propulsion system interactions on V/STOL fighter aircraft and other highly integrated configurations can be studied. This paper describes the status of the compact multimission aircraft propulsion simulator (CMAPS) technology. Three CMAPS units have accumulated a total of 340 hr during approximately 1-1/2 yr of static and wind-tunnel testing. A wind-tunnel test of a twin-engine CMAPS-equipped close-coupled canard-wing V/STOL model configuration with nonaxisymmetric nozzles was recently completed. During this test approximately 140 total hours were logged on two CMAPS units, indicating that the rotating machinery is reliable and that the CMAPS and associated control system provide a usable test tool. However, additional development is required to correct a drive manifold O-ring problem that limits the engine-pressure-ratio (EPR) to approximately 3.5.
Spider's Stratagem

"While we tend to conceive of the operations of the mind as uni fied and transparent, he [Daniel Dennett, author of Consciousness Explained] suggests that they are chaotic and opaque. There is no invisible 'boss' in the brain, no 'central meaner,' no unitary self in command of our activities and utterances. There is no internal spectator of a 'Cartesian theatre' in our heads to applaud the march of consciousness across its stage." (Adam Zeman)
High tenacity, high modulus conducting polyaniline composite fibers

High tenacity, high modulus electrically conducting Polyaniline (PAn) composite fibers are prepared from air-gap spinning of lyotropic PAn/poly(p-phenylene terephthalamide), PPD-T, sulfuric acid solutions. For example, tenacity and modulus are in the range of 16 gpd and 270 gpd, respectively for 30 w.% PAn composite fiber. PAn is finely dispersed around PPD-T domains and is oriented parallel to fiber axis. PAn is also sulfonated during the processing and does not require external doping to render the fibers conductive. Electrical conductivity of the fibers continue to turn on even at the concentration as low as below 5 w.% PAn. The fiber containing 30 w.% PAn has conductivity in the range of 0.1 S/cm.
Postresonance electromagnetic absorption by man and animals

A surface integral equation (SIE) method is used to calculate the specific absorption rate (SAR) in spherically capped cylindrical models irradiated by an axially incident electromagnetic plane wave (K polarization) in a frequency range for which calculations previously have not been available (80-400 MHz for man models). In the SIE method, the electromagnetic (EM) field relations are formulated in terms of electric and magnetic currents on the surface of the model. The average SAR is calculated from the far scattered EM fields by means of the forward scattering theorem. SAR data calculated by the SIE method agree with data calculated by the extended boundary condition method (EBCM) for frequencies up to 80 MHz (the upper frequency limit of the EBCM) for man models. For rat models exposed to 1-3 GHz radiation, reasonable agreement was also obtained with the limited experimental data available.
Effect of Biofeedback-Assisted Relaxation Training on Foot Ulcer Healing

A prospective, randomized study was conducted to determine the effect of biofeedback-assisted relaxation training on foot ulcer healing. For patients with chronic nonhealing foot ulcers, medical care was combined with a standardized biofeedback-assisted relaxation training program in the experimental group. The intervention was designed to increase peripheral perfusion, thereby promoting healing. A total of 32 patients with chronic nonhealing ulcers participated in the study. In the experimental group, 14 out of 16 ulcers (87.5%) healed, as compared with 7 out of 16 ulcers (43.8%) in the control group.
Affine representations of generalized quadrangles

Abstract It is shown that a general construction due to Tits of finite generalized quadrangles (4-gons) yields the “classical” examples and only these except when the characteristic of the underlying field is 2. In that case an affine representation of the quadrangles is used to obtain results concerning the self-duality and self-polarity of a “nice” class of quadrangles.
Rapid conversion of an IT degree program to online delivery: impact, problems, solutions and challenges

At our institution, online delivery was initially seen as a way to extend the geographic reach of a specialized upper-division degree program, the Bachelor of Science in Applied Sciences (BSAS), targeting holders of community college Associates in Science (AS) degrees, with the hoped-for impact of increasing enrollment. This program shared many required courses with our flagship program, the BS in Information Technology (BSIT), including the upper-division entry point for both programs, CGS3303 IT Concepts. Implementing this course in an asynchronous online mode resulted in an increase in enrollment from 17 (fall, 2007) to 70 (spring, 2008); most of these 70 students identified as BSIT, leading us to fast-track conversion to online modes for all of our core courses and electives. This accelerated pace of online development presented many challenges and difficulties, including ensuring the quality of our finished course product. Faculty buy-in, assisted by a stipend program for online development, was essential, as was the presence of quality instructional technology support. An NSF-funded infrastructure (SOFTICE) allowed the offering of problematic laboratory courses (Operating Systems, Networks) safely and securely in an online mode. A course quality review process was implemented as part of the stipend program, which also largely resolved intellectual property issues. Nonetheless, remaining are some issues and concerns, which are discussed in this paper. Recommendations, observations and suggested processes are included for those who may be considering transitioning an IT degree program to online delivery.
Hyperpolarized 129Xe NMR Investigation of Ammonia Borane in Mesoporous Silica

Hyperpolarized (HP) 129Xe NMR was used to probe the porosity of mesoporous silica (MCM) infused with ammonia borane (AB). Variable-temperature HP 129Xe NMR measurements have been systematically carried out on a series of MCM-41 materials with AB loading ranging from 33 to 75 wt % (1:2 to 3:1 AB:MCM). Three distinct types of pore environments are clearly evident: pristine mesopores, pores coated with AB inside the meso-channels, and interparticle spacing formed from AB aggregates outside the meso-channels. We found similarly uniform coating of AB on mesoporous silica channels with 1:2 and 1:1 AB:MCM loading (ratio of weight percent). When the loading of AB to MCM is greater than 1:1, AB starts to aggregate outside the meso-channels. Further increases in loading (≥3:1) result in the formation of partially blocked meso-channels as a result of excessive AB. The detailed information obtained from this study on how supported AB resides in nanoporous channels and how it evolves with the increase of AB loading is...
Effect of Extracellular Signal-regulated Kinase on p53 Accumulation in Response to Cisplatin

The p53 tumor suppressor protein is a transcription factor that plays a major role in the DNA damage response. After DNA damage, p53 levels increase due primarily to stabilization of the protein. The molecular mechanisms leading to stabilization of p53 after DNA damage have not been completely elucidated. Recently we reported that cisplatin treatment activated extracellular signal-regulated kinase 1 and 2 (ERK1/2) and that inhibition of ERK1/2 resulted in enhanced sensitivity to cisplatin. In the present study, we examined the potential role of ERK1/2 activation in regulation of the p53 response to cisplatin. In the ovarian carcinoma cell line A2780, inhibition of ERK1/2 activation with the mitogen-activated protein kinase/ERK kinase 1 (MEK1) inhibitor PD98059 resulted in decreased p53 protein half-life and diminished accumulation of p53 protein during exposure to cisplatin. We also demonstrated that p53 protein co-immunoprecipitated with ERK1/2 protein and was phosphorylated by activated recombinant murine ERK2 in vitro. Furthermore, PD98059 decreased the phosphorylation of p53 at serine 15 during cisplatin exposure, suggesting that ERK1/2 mediates in part phosphorylation of p53 during the cisplatin DNA response. These results strongly suggest that cisplatin-induced ERK activation is an up-stream regulator of the p53 response to DNA damage caused by cisplatin.
The ultrastructure of bacterial plaque attached to the gingiva of man.

Abstract The ultrastructure of bacterial plaque attached to human gingiva was studied by transmission electron microscopy using 6 per cent glutaraldehyde in buffered 70 per cent ethanol as a fixative, with uranium and lead staining or with ruthenium red-osmium tetroxide as a postfixative. In general, gingival plaque has a layered structure, in which various coccoid forms of bacteria are attached to the epithelial cells and the cocci themselves are overlain by a number of different rod-shaped or filamentous forms. The mosaic of microcolonies is held together by direct contact of cells and especially by an extracellular matrix of fibrillar material. This matrix varies in morphology and is associated particularly with the coccoid forms. In spite of the differences between their sites of attachment, the general structure of gingival plaque resembles that of dental plaque, although some variations are found. The similarity presumably eflects the dominance of the effect of the macro-environment of the mouth over the effect(s) of the micro-environment of the surfaces.
High risk of Kaposi's sarcoma and central nervous system lymphoma in the same individuals: A finding related to acquired immunodeficiency syndrome

Kaposi's sarcoma and central nervous system (CNS) lymphoma are the 2 most common malignancies related to HIV infection. To investigate the association between Kaposi's sarcoma and CNS lymphoma, a population-based retrospective cohort study was conducted. Using U.S. Surveillance, Epidemiology and End Results Program data, the gender-specific age- and calendar year-adjusted standardized incidence ratios were calculated for the pre-AIDS (1973-1980) and AIDS (1981-1990) eras, as an estimate of the relative risk (RR) of developing one condition following another. For the AIDS era in men, the RR of CNS lymphoma following Kaposi's sarcoma was 979.7 and that of Kaposi's sarcoma following CNS lymphoma was 231.1 There were no instances of the co-occurrence of these malignancies in women in either era or in men for the pre-AIDS era. The extremely high RRs for the co-occurrence of Kaposi's sarcoma and CNS lymphoma in men during the AIDS era suggests that the association of these malignancies occurs within the same HIV-infected individuals.
Genetic Studies of the Macushi and Wapishana Indians I. Rare Genetic Variants and a "Private Polymorphism" of Esterase A

Blood samples from 509 Macushi and 623 Wapishana Amerindians of Northern Brazil and Southern Guyana have been analyzed with reference to the occurrence of rare variants and genetic polymorphisms of the following 25 systems: (i) Erythrocyte enzymes: acid phosphatase-1, adenosine deaminase, adenylate kinase-k, carbonic anhydrase-1, carbonic anhydrase-2, esterase A1,2,3, esterase D, galactose-1-phosphate uridyltransferase, isocitrate dehydrogenase, lactate dehydrogenase, malate dehydrogenase, nucleoside phosphorylase, peptidase A, peptidase B, phosphoglucomutase 1, phosphoglucomutase 2, phosphogluconate dehydrogenase, phosphohexoseisomerase, triosephosphate isomerase and (ii) Serum proteins: albumin, ceruloplasmin, haptoglobin, hemoglobin A, hemoglobin A2 and transferrin. Fifteen different rare variants were detected, involving 11 of these systems. In addition, a previously undescribed variant of ESA1,2,3 which achieves polymorphic proportions in both these tribes is described. Excluding this variant, the frequency of rare variants is 1.1/1000 in 12510 determinations in the Macushi and 4.7/1000 in 15 396 determinations in the Wapishana. The ESA1,2,3, polymorphism was not observed in 382 Makiritare, 232 Yanomama, 146 Piaroa, 404 Cayapo, 190 Kraho and 112 Moro. Irregularities in the intratribal distribution of this polymorphism in the Macushi and Wapishana render a decision as to the tribe of origin impossible at present. Gene frequencies are also given for previosly described polymorphisms of 5 systems: haptoglobin, phosphoglucomutase 1, erythrocyte acid phosphatase, esterase D, and galactose-1-phosphate-uridyl-transferase.
An Animal Model to Investigate Effectiveness and Safety of Conducted Energy Weapons (Including TASER® Devices)*

Conducted energy weapons (CEWs) are used by law-enforcement personnel to incapacitate individuals quickly and effectively, without causing lethality. CEWs have been deployed for relatively long or repeated exposures during law-enforcement operations. The purpose of this technical note is to describe, in detail, some aspects of an anesthetized swine model used in our laboratory and to answer specific questions related to the model. In particular, tiletamine/zolazepam-induced, propofol-maintained anesthesia appears to be a useful technique for studying effects of CEW applications on muscle contraction and blood factors such as muscle enzymes. Because effects of CEWs on breathing have not been fully elucidated, a spontaneously breathing model is preferable to one in which mechanical ventilation is supplied. Placement of the swine in a supine position may facilitate measurement of muscle contractions, without compromising other physiological parameters.
Signal-detection models for multidimensional stimuli: probability distributions and combination rules

Abstract Probabilistic independence among multiple random variables (e.g., among the outputs of multiple spatial-frequency channels) has been invoked to explain two effects found with many kinds of stimuli: increments in detection performance due to “probability summation” and decrements in detection and identification performance due to “extrinsic uncertainty.” Quantitative predictions of such effects, however, depend on the precise assumptions. Here we calculate predictions from multidimensional signal-detection theory assuming any of several different probability distributions characterizing the random variables (including two-state, Gaussian, exponential, and double-exponential distributions) and either of two rules for combining the multiple random variables into a single decision variable (taking the maximum or summing them). In general, the probability distributions predicting shallower ROC curves predict greater increments due to summation but smaller decrements due to extrinsic uncertainty. Some probability distributions yield steep-enough ROC curves to actually predict decrements due to summation in blocked-summation experiments. Probability distribution matters much less for intermixed-summation than for blocked-summation predictions. Of the two combination rules, the sum-of-outputs rule usually predicts both greater increments due to summation and greater decrements due to extrinsic uncertainty. Put another way, of the two combination rules, the sum-of-outputs rule usually predicts better performance on the compound stimulus under any condition but worse performance on simple stimuli under intermixed conditions.
MODTRAN cloud and multiple scattering upgrades with application to AVIRIS

Abstract Recent upgrades to the MODTRAN atmospheric radiation code improve the accuracy of its radiance predictions, especially in the presence of clouds and thick aerosols, and for multiple scattering in regions of strong molecular line absorption. The current public-released version of MODTRAN (MODTRAN3.7) features a generalized specification of cloud properties, while the current research version of MODTRAN (MODTRAN4) implements a correlated-k (CK) approach for more accurate calculation of multiply scattered radiance. Comparisons to cloud measurements demonstrate the viability of the CK approach. The impact of these upgrades on predictions for AVIRIS viewing scenarios is discussed for both clear and clouded skies; the CK approach provides refined predictions for AVIRIS nadir and near-nadir viewing.
Total inhibition of 1O2-induced oxidative damage to guanine bases of DNA/RNA by turmeric extracts

Abstract The guanine base of nucleic acids is known to be very reactive towards degradation by 1O2-induced oxidative stress. Oxidative reactions of DNA are linked to many human diseases including cancer. Among the various forms of reactive O2 species ( OH, 1O2 or O 2 - ), the oxidative stress caused by 1O2 is of particular physiologic importance because of its selectively long life in aqueous medium and its ability to diffuse through a cell membrane. In this study we investigated the degradation of a model compound guanosine (Guo) by 1O2, which was generated by riboflavin-induced photosensitization and by molybdate ion catalyzed disproportionation of H2O2. We observed the remarkable ability of an aqueous and alcoholic extracts of Turmeric (Curcuma longa) as an extraordinary scavenger of 1O2 to completely inhibit the degradation of Guo. The alcoholic extracts were more effective in their antioxidant activity than the corresponding water extract. This naturally occurring antioxidant offers a most economical supplement to protect biologically significant molecules from the oxidative stress induced by 1O2.
Pre-Oxidation Anneal Kinetics: Interface Degradation of Thin SIO2 Films on Silicon

Abstract : The high temperature anneal of hydrogen terminated silicon has been shown to etch and roughen its surface. We attempt to describe the degree of this roughness and the time scale on which it occurs using several electrical measurements: excess direct tunneling currents, dielectric breakdown and the oscillations in the Fowler-Nordheim tunneling currents. From these results we draw conclusions on the time and water content dependence of pre-oxidation annealing on the microroughness of the Si/SiO2 interface.
Control of ventilation in Ondine's curse

O N D I N E' S C U R S E, or central alveolar hypoventilation, is a rare condition characterized by marked depression of respiratory drive during sleep. This disorder is believed to result from failure of central chemoreceptors, thought to be located normally in the ventrolateral area of the medulla.' Although there have been numerous reports of CH since the initial well-studied case in 1955, 2 few have concerned patients whose symptoms were present since birth. ~ ~ We report here an evaluation of ventilatory control during sleep in a child with congenital CH.
Optimal Rangeland Stocking Decisions Under Stochastic and Climate-Impacted Weather

A Stochastic Dynamic Programming (SDP) model is developed to analyze optimal stocking rates in the face of weather uncertainty and potential climate change projections. The model extends previous work modeling grazing as a predator-prey relationship. Attention is given to profit maximizing decisions when growing season precipitation is unknown. Comparisons are made across results from a model that utilizes constant growing season precipitation in all years. Results suggest that optimal stocking rates and profitability decrease in climate change scenarios with increased precipitation variability as compared to the historical stochastic weather scenario.
Why Is Enacted Social Support Associated With Increased Distress? Using Simulation to Test Two Possible Sources of Spuriousness

Although perceiving that social support is available is often associated with psychological benefits in times of stress, there is evidence that actually receiving support is associated with increased distress. To assess whether this latter association could be spurious, the authors conducted computer simulation studies to examine two theoretical models that could give rise to it. Study 1 examined a process whereby distress leads to provision of support rather than the reverse. Study 2 examined a process whereby an adverse event increases both support and distress. In both cases, substantial spurious associations were produced only when parameter values were markedly unrealistic. It was concluded that these possible sources of spuriousness are insufficient to explain the association between support and distress found in naturalistic studies.
HEALTH SCREENING: I

L. G. is a 37-year-old black female, first seen in the Nephrology Clinic in May 1987 with a serum creatinine of 3.7 mg/dl. Ultrasound studies revealed bilaterally contracted kidneys. Over the next 18 months, the patient's renal function continued to deteriorate and she was started on hemodialysis. She stayed on hemodialysis for about one year but finally changed to continuous ambulatory peritoneal dialysis (CAPD) because of multiple vascular access problems. Over the next two and a half years the patient did well on CAPD. Then on a routine breast self-examination, she discovered a firm, approximately 1.5 cm mass below the right nipple. A mammogram was done which revealed the lesion to be suspicious for malignancy. Biopsy of the lesion revealed a poorly differentiated mammary carcinoma. The patient subsequently underwent a right mastectomy without complication. Past medical history includes cholecystectomy which was done about seven years previously, and an abnormal Tiberoxime Stress Test, but a normal coronary angiogram done as part of her renal transplant evaluation. About four years ago, the patient complained of swelling in the right breast. She was seen by a surgeon and had a mammogram performed which was normal. She had a follow-up mammogram in 1991 which was again normal.
Growing Cholesterol‐Dependent NS0 Myeloma Cell Line in the Wave Bioreactor System: Overcoming Cholesterol‐Polymer Interaction by Using Pretreated Polymer or Inert Fluorinated Ethylene Propylene

Difficulty in growing cholesterol-dependent NS0 cells in the Wave bioreactor using the original low-density polypropylene (LDPE) bags has been encountered. It has been shown that in these bags chemically defined cholesterol is depleted from solution and therefore unavailable for the cells. Our data suggest that the cause of the depletion is not chemical but is due to the physical structure of the polymer. It is proposed that polymer structures with inkbottle pores retain cholesterol, whereas structures with V-shaped pores adsorb cholesterol reversibly. Ultra-low-density polyethylene (ULDPE) bags can support cell growth but need to be pretreated with excess cholesterol. Another material, fluorinated ethylene propylene (FEP) does not need to be pretreated and is found to be superior (negligible cholesterol adsorption) as a result of its inert characteristics.