cssi/SciSciGPT-SciSciNet huggingface dataset:
Physiological Reactivity to Graded Levels of Cognitive Workload across Three Age Groups: An On-Road Evaluation:

This study examined the sensitivity of two physiological measures to the demand of structured cognitive tasks representing low, moderate and relatively high levels of secondary cognitive workload during actual highway driving. In a sample of 108 relatively healthy drivers, balanced by gender, and drawn from three age groups (20–29, 40–49, and 60–69), both heart rate and skin conductance were found to increase in a statistically significant and relatively linear fashion across 4 levels of workload. Issues associated with the study of sensitivity, task engagement and age are considered.
Gas transport resulting from plasma-scalpel surgery

The extent of absorption and the intravascular itinerary of plasma-scalpel operating gas have been investigated by monitoring the intravascular and exhaled argon partial pressures during canine hepatic surgery. The blood-gas analysis was performed continuously, using a mass spectrometer to measure dissolved argon, and, periodically, using a gas chromatograph to quantify all argon ingested, including emboli. To quantify the amount of argon lost through the pulmonary circulation, monitoring took place in the right atrium and the aorta. Experimental results show that the amount of argon absorbed at the incision site and transported through the bloodstream may increase the dissolved argon concentration in the right atrium by as much as 150%. The results also indicate that argon may be present as emboli in the bloodstream, but that argon storage in the tissues is insignificant. The argon concentration in the aorta does not noticeably increase; hence the excess argon is exhaled within one circulation through the pulmonary circuit. These observations were substantiated by the use of an ultrasonic Doppler flowmeter to check for the presence of gas emboli at various locations.
High performance & low latency in solid-state drives through redundancy

Solid-state drives are becoming increasingly popular in enterprise storage systems, playing the role of large caches and permanent storage. Although SSDs provide faster random access than hard-drives, their performance under read/write workloads is highly variable often exceeding that of hard-drives (e.g., taking 100ms for a single read). Many systems with mixed workloads have low latency requirements, or require predictable performance and guarantees. In such cases, the performance variance of SSDs becomes a problem for both predictability and raw performance.In this paper, we propose a design based on redundancy, which provides high performance and low latency for reads under read/write workloads by physically separating reads from writes. More specifically, reads achieve read-only performance while writes perform at least as good as before. We evaluate our design using micro-benchmarks and real traces, illustrating the performance benefits of read/write separation in solid-state drives.
Low back pain and myalgias in acute and relapsed mast cell leukemia: a case report.

Mast cell leukemia is a rare, severe disease that may manifest through an array of clinical presentations, including vasomotor flushing and hypotension. Leukemic infiltrate of muscle and bone may rarely occur, resulting in nonspecific myalgias, bony pain, and neuropathic pain secondary to compression of nerves by bone. Mast cell leukemia as a clinical entity has not been well described. We present the case of a 25-year-old man with a remote medical history of germ cell tumor who was initially diagnosed with mast cell leukemia after presenting with low back pain. One and a half years later, the patient presented with a chief complaint of back pain and myalgias and was found to have relapsed mast cell leukemia. Medical management and, specifically, rehabilitation of these patients can be extremely difficult. This report shows the complex management of patients with mast cell leukemia.
Actinide abundances in ordinary chondrites.

Measurements of ^(244)Pu fission Xe, U, Th, and light REE (LREE) abundances, along with modal petrographic determinations of phosphate abundances, were carried out on equilibrated ordinary chondrites in order to define better the solar system Pu abundance and to determine the degree of variation of actinide and LREE abundances. Our data permit comparison of the directly measured Pu/U ratio with that determined indirectly as (Pu/Nd) × (Nd/U) assuming that Pu behaves chemically as a LREE. Except for Guarena, and perhaps H chondrites in general, Pu concentrations are similar to that determined previously for St. Severin, although less precise because of higher trapped Xe contents. Trapped ^(130Xe)/_(136Xe) ratios appear to vary from meteorite to meteorite, but, relative to AVCC, all are similar in the sense of having less of the interstellar heavy Xe found in carbonaceous chondrite acid residues. The Pu/U and Pu/Nd ratios are consistent with previous data for St. Severin, but both tend to be slightly higher than those inferred from previous data on Angra dos Reis. Although significant variations exist, the distribution of our Th/U ratios, along with other precise isotope dilution data for ordinary chondrites, is rather symmetric about the CI chondrite value; however, actinide/(LREE) ratios are systematically lower than the CI value. Variations in actinide or LREE absolute and relative abundances are interpreted as reflecting differences in the proportions and/or compositions of more primitive components (chondrules and CAI materials?) incorporated into different regions of the ordinary chondrite parent bodies. The observed variations of Th/U, Nd/U, or Ce/U suggest that measurements of Pu/U on any single equilibrated ordinary chondrite specimen, such as St. Severin, should statistically be within ±20–30% of the average solar system value, although it is also clear that anomalous samples exist.
Streptomycinoid Antibiotics: Synergism by Puromycin

Puromycin synergizes the lethal action of streptomycin and related antibiotics. This is interpreted to mean that puromycin action uncovers a sensitive site (or sites) on the 30S ribosome. The streptomycinoid antibiotics can then associate more readily with the ribosome and inhibit further synthesis of valid protein.
Collection and Expansion of Single Cells and Colonies Released from a Micropallet Array

The ability to selectively grow out individual cells possessing unique characteristics from within a mixed population is of widespread importance for biomedical investigations. Generation of genetically engineered cell lines, transformation studies, cell-based assays, and stem cell studies are examples where single-cell cloning is of immense value. The vast majority of mammalian cells grow adherent to a surface; therefore, positive selection followed by cloning of cells while the cells remain adherent to their growth surface is an important goal. We recently demonstrated a microfabricated cell array combined with laser-based release of individual array elements for positive selection of single cells. In the current work, a strategy to collect single cells for clonal expansion is described. The system enabled cloning of individual cells with 80−90% efficiency. Single cells were selected and cloned from small populations of fewer than 10 000 cells. Strategies used by cells to migrate from the pallets to for...
A Transluminally Created Abdominal Aortic Aneurysm Model

Purpose To develop a stable, transluminally created abdominal aortic aneurysm (AAA) within a live animal model. Materials and Methods Eight mongrel dogs were utilized to evaluate a new, catheter-based technique for the creation of an AAA. With use of a standard angioplasty balloon and a balloon-expandable intravascular metallic stent, the infrarenal abdominal aorta was overdilated to twice its measured diameter into a fusiform shape AAA in eight dogs. At 30 days, aortography was performed, the dogs were killed, and the aorta was resected and evaluated for histopathology. Results Seven of the eight dogs that underwent transluminal AAA creation survived the initial procedure. A stable, fusiform AAA was successfully created in these seven dogs. At 30 days, repeat angiography and histologic examination confirmed that the seven AAAs were still twice the diameter of the normal aorta (a four-fold increase in luminal area), that the branch arteries remained patent, and that the lumen was endothelialized. One of the eight dogs was killed 9 hours after the procedure because of inability to awaken from anesthesia. Gross and histopathologic results in this one dog also demonstrated an intact aorta containing an AAA. Conclusions A stable, infrarenal AAA model can be successfully created in the canine species with use of standard catheter-based techniques and equipment. This model can be used to test emerging endovascular treatments of AAA.
A method of analyzing individual cortical responses to auditory stimuli

Abstract A method is proposed which quantifies the degree to which a specified response is present in each single acoustic stimulus. The specified response is described by a second order linear differential equation. This wave form is preset in a function generator. The EEG and this template are multiplid in an analog computer. The second integral of these products is read out on an EEG oscillograph as the degree to which the specified response is present. The variables involved in this analysis are discussed.
Model-based predictive control strategy for a solid oxide fuel cell system integrated with a turbocharger

This paper describes a model-based control design for a solid oxide fuel cell and gas turbine (SOFC/GT) combined cycle system. One-step ahead predictive control is formulated to (1) meet the power demand effectively, (2) handle the multiple constraints of the hybrid system, and (3) minimize the fuel consumption. An SOFC/GT control strategy with two sequential optimization loops is proposed. The primary controller is designed to achieve the system net power, the targeted fuel utilization, and high fuel economy by manipulating the fuel cell current and the anode fuel flow rate. The secondary controller minimizes the fuel cell temperature variation during transients by adjusting the generator load. Simulation results show that the control strategy is capable of achieving fast load transitions while maintaining the fuel utilization within the feasible range. The one-step ahead prediction control is shown to provide the benefits of on-line optimization without incurring large computation burden.
Obesity, Physical Activity, and Sedentary Behavior of Youth With Learning Disabilities and ADHD

Obesity, physical activity, and sedentary behavior in childhood are important indicators of present and future health and are associated with school-related outcomes such as academic achievement, behavior, peer relationships, and self-esteem. Using logistic regression models that controlled for gender, age, ethnicity/race, and socioeconomic status, we investigated the likelihood that youth with learning disabilities (LD) and attention-deficit/hyperactivity disorder (ADHD) are obese, physically active, and sedentary using a nationally representative sample of 45,897 youth in the United States from 10 to 17 years of age. Results indicated that youth with comorbid LD/ADHD were significantly more likely than peers without LD or ADHD to be obese; that youth with LD only, ADHD only, and comorbid LD/ADHD were significantly less likely to meet recommended levels of physical activity; and that youth with LD only were significantly more likely to exceed recommended levels of sedentary behavior. Medication status mediated outcomes for youth with ADHD. We offer school-based recommendations for improving health-related outcomes for students with LD and ADHD.
Investigation of conceptual and numerical approaches for evaluating moisture, gas, chemical, and heat transport in fractured unsaturated rock

Abstract We investigate the utility and appropriateness of various conceptual and numerical approaches for modeling several flow and transport processes in the unsaturated zone (UZ) at Yucca Mountain, NV, using a one-dimensional (1-D) column extracted from a three-dimensional (3-D) UZ site-scale model. Simulations of steady-state and transient moisture flow, transient gas flow, tracer transport, and thermal loading scenarios are performed, using a variety of numerical approaches to treat fracture–matrix (F–M) interactions, including an effective continuum model (ECM) and several varieties of dual-continua models. For the dual-continua models, we investigate the effect of varying the number of matrix gridblocks per fracture gridblock, the formulation applied for calculating F–M interface area, and whether or not global matrix-to-matrix flow occurs (dual-permeability vs. dual-porosity models). The key findings of the work based on a 1-D column are as follows. For steady-state moisture flow, most of the numerical and conceptual models provide similar results for saturation and fracture flow profiles. The ECM adequately models the steady-state processes because the system is not too far away from F–M equilibrium. For both transient moisture flow and transient transport in a steady flow field, the ECM is not adequate in general. Within the dual-continua models, the formulation for F–M interface area can have a major effect on the hydrodynamic response to an infiltration pulse and tracer arrival at various horizons, with fracture responses becoming earlier as F–M interface area decreases. The number of matrix blocks also has a significant effect on response time, with the more accurate multi-matrix-gridblock models yielding slower fracture response times. For transient gas flow arising from barometric pressure variations, the ECM adequately models the process, because F–M gas flow occurs rapidly compared to the time scale of the barometric pressure variations. For thermal loading, preliminary studies indicate that the ECM does not capture all the significant physical processes, because rapid fluid and heat flow can occur in the fractures before the matrix has a chance to equilibrate.
Genotype effects on the antioxidant enzymes activity and mRNA expression in liver and kidney tissues of autoimmune-prone MRL/McJ-lpr/lpr mice

Congeneic pairs of MKL/lpr and MRL/ + +(+ / +) mice differ in incidence of autoantibodies, lymphoproliferative disease and survival, characteristics that are linked to immunological abnormalities. MRL/lpr mice have a significantly shorter life span compared to +/+ mice. Because a weak antioxidant defense and an increased generation of free radicals are generally implicated in the severity of many autoimmune diseases, the present study was undertaken to compare the influence of genotype on lipid composition, lipid peroxidation and expression of mRNA, and activity of antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GSH-Px) and Superoxide dismutase (SOD) in the livers and kidneys of these mice. The expression of SOD, GSH-Px and CAT mRNAs was significantly higher (P < 0.05) in the livers of + / + mice, while in the kidneys only SOD expression was found significantly higher in + / + mice when compared to MRL/lpr mice. Further, the activity of cytosolic SOD and GSH-Px was also found significantly higher (P < 0.001) in the livers of + / + mice. Both livers and kidneys of MRL/lpr mice exhibited significantly higher levels of arachidonic acid (20:4(n − 6)), significantly higher generation of thiobarbituric acid reactive substances (TBARS) and higher estimated peroxidation index than the + / + mice. In addition, the MRL/lpr mice had higher levels of serum anti-cardiolipin antibodies. In summary, the results from the present study indicate that besides several immune-related abnormalities, the MRL/lpr mice may exhibit their inability to cope with oxidative stress due to a poor antioxidant defense system. This weak defense system is revealed by lower mRNA expression of antioxidant enzymes, weak SOD and GSH-Px enzyme activities, and an increased level of 20:4(n − 6) in liver lipids, which in turn may increase generation of free radicals in the livers and kidneys, thus making the MRL/lpr mice more susceptible to autoimmune disease than the + / + mice.
Postmortem molecular analysis of SCN5A defects in sudden infant death syndrome.

Context Fatal arrhythmias from occult long QT syndrome may be responsible for some cases of sudden infant death syndrome (SIDS). Because patients who have long QT syndrome with sodium channel gene (SCN5A) defects have an increased frequency of cardiac events during sleep, and a recent case is reported of a sporadic SCN5Amutation in an infant with near SIDS, SCN5A has emerged as the leading candidate ion channel gene for SIDS. Objective To determine the prevalence and functional properties of SCN5A mutations in SIDS. Design, Setting, and Subjects Postmortem molecular analysis of 93 cases of SIDS or undetermined infant death identified by the Medical Examiner's Office of the Arkansas State Crime Laboratory between September 1997 and August 1999. GenomicDNA was extracted from frozen myocardium and subjected to SCN5A mutational analyses. Missense mutations were incorporated into the human heart sodium channel α subunit by mutagenesis, transiently transfected into human embryonic kidney cells, and characterized electrophysiologically. Main Outcome Measures Molecular and functional characterization of SCN5A defects. Results Two of the 93 cases of SIDS possessed SCN5A mutations: a 6-week-old white male with an A997S missense mutation in exon 17 and a 1-month old white male with an R1826H mutation in exon 28. These 2 distinct mutations occurred in highly conserved regions of the sodium channel and were absent in 400 control patients (800 alleles). Functionally, the A997S and R1826H mutant channels expressed a sodium current characterized by slower decay and a 2- to 3-fold increase in late sodium current. Conclusion Approximately 2% of this prospective, population-based cohort of SIDS cases had an identifiable SCN5A channel defect, suggesting that mutations in cardiac ion channels may provide a lethal arrhythmogenic substrate in some infants at risk for SIDS.
Pneumocystis carinii thyroiditis

A 38-year-old black man with a history of acquired immunodeficiency syndrome associated with intravenous drug abuse presented with two weeks of left-sided neck swelling. Results of thyroid function tests were within normal limits. Thyroid scan demonstrated nonvisualization of the left lobe. Fine-needle aspiration of the thyroid revealed the presence of Pneumocystis carinii organisms in the thyroid tissue. Although chest radiography and computerized tomography of the chest detected several nodules and cavitary lesions, the results of bronchoalveolar lavage and transbronchial biopsy were negative for P. carinii. The patient showed a response to treatment with trimethoprim/sulfamethoxazole. Thyroidal involvement with P. carinii has previously been documented only in the setting of overwhelming, fatal pulmonary infection. The current case expands the clinical spectrum of extrapulmonary pneumocystosis and documents its successful treatment.
Further exploration in primitives of meaning

Semantic mismatch between systems is due, in part, to the grouping together of terms who have representations of meaning in different levels of granularity (from different perspectives), and which are composed together into distinct groupings by their own systems of origin. It has been proposed that by referencing these representations when decomposed into elemental concepts (referred to here as primitives of meaning) can assist in interoperability. Insofar as systems describing similar referents are operating within a similar community, the underlying concepts are near-universal (within that community) enough to accommodate this.By decomposing a system's groups of composed terms into primitives of meaning, the building blocks that can be reassembled into the compositions required by another group (of another system, for instance) can be made apparent. While such a de-composition could serve as the basis for an interoperability enabler, having the decomposition available as a common descriptor to highlight areas of semantic misalignment should prove in itself useful.Taking doctrinal statements for US small unit infantry actions as one semantic system, we show how the elemental ideas that are grouped together into commands can be identified and isolated for reconstruction into other groupings. This is the first research step towards relying on primitives of meaning for interoperability.
Output Power Smoothing for Wind Turbine Permanent Magnet Synchronous Generators Using Rotor Inertia

Abstract Due to wind speed variations, the output power of wind turbines fluctuates. This power fluctuation can cause frequency deviations and power outage, particularly when wind power penetration is significant. Energy storage devices, such as batteries, ultracapacitors, super inductors, and flywheels can be utilized in a hybrid system to solve this problem. These methods are effective, but they impose a significant additional cost to the system. This article presents a novel control method to mitigate the power fluctuations using the rotor inertia as an energy storage component. Therefore, the additional energy storage system is not required. The proposed method is also modified to obtain better energy capturing efficiency. The efficiency of the algorithm is evaluated based on developed equations. The energy extracting capability using this method is comparable to other methods such as the maximum power extraction algorithm. Simulation studies for various cases are performed on a permanent magnet synch...
A TRPC6-Dependent Pathway for Myofibroblast Transdifferentiation and Wound Healing In Vivo

After injury or cytokine stimulation, fibroblasts transdifferentiate into myofibroblasts, contractile cells that secrete extracellular matrix for wound healing and tissue remodeling. Here, a genome-wide screen identified TRPC6, a Ca(2+) channel necessary and sufficient for myofibroblast transformation. TRPC6 overexpression fully activated myofibroblast transformation, while fibroblasts lacking Trpc6 were refractory to transforming growth factor β (TGF-β) and angiotensin II-induced transdifferentiation. Trpc6 gene-deleted mice showed impaired dermal and cardiac wound healing after injury. The profibrotic ligands TGF-β and angiotensin II induced TRPC6 expression through p38 mitogen-activated protein kinase (MAPK) serum response factor (SRF) signaling via the TRPC6 promoter. Once induced, TRPC6 activates the Ca(2+)-responsive protein phosphatase calcineurin, which itself induced myofibroblast transdifferentiation. Moreover, inhibition of calcineurin prevented TRPC6-dependent transdifferentiation and dermal wound healing. These results demonstrate an obligate function for TRPC6 and calcineurin in promoting myofibroblast differentiation, suggesting a comprehensive pathway for myofibroblast formation in conjunction with TGF-β, p38 MAPK, and SRF.
Influence of Bisolute Competition on the Desorption Kinetics of Polycyclic Aromatic Hydrocarbons in Soil

The dual-mode (partition/hole-filling) model of soil organic matter (SOM) as a heterogeneous polymerlike sorbent of hydrophobic compounds predicts that a competing solute will accelerate diffusion of the primary solute by blocking the holes, allowing the principal solute to move faster through the SOM matrix. We tested this hypothesis with phenanthrene as the primary solute and pyrene as the competing solute in two sterile soils of widely different organic carbon content (1.4 and 43.9%). Two- and 33-d isotherms of phenanthrene in both soils were nonlinear, indicating a heterogeneous distribution of sites. Pyrene suppressed phenanthrene sorption and increased the linearity of its isotherm. Uptake (adsorption) rates were measured in batch systems after preincubating with pyrene. Desorption was measured by the sequential dilution technique at constant pyrene concentration in the supernatant. The design of the experiment precluded comparison of adsorption rates, but desorption rates increased significantly (b...
Reliable and efficient reprogramming in sensor networks

Retasking and remote programming of sensor networks is an essential functionality to make these networks practical and effective. As the availability of more capable sensor nodes increases and new functional implementations continue to be proposed, these large collections of wireless nodes will need the ability to update and upgrade the software packages they are running. In order to do this, the new binary file must be distributed to all nodes in the network. Making a physical connection with each individual node is impractical in large wireless networks. Standard flooding mechanisms are too energy-costly and computationally expensive and they may interfere with the network's current tasks. A reliable method for distributing new code or binary files to every node in a wireless sensor network is needed. We propose a reprogramming/retasking framework for sensor networks that is energy efficient, responsive, and reliable, while maintaining a stable network.
Thermal Transient Characteristics of Flip Chip High Power Light Emitting Diodes

The die-attached quality and the thermal transient characteristics of high power flip chip light emitting diodes (LEDs) are investigated using thermal transient tester. Various die-attached materials were utilized to compare the difference in their thermal resistances and long term performance. By applying accelerated aging stress, the deterioration rates at the die-attached layers were obtained. Numerical simulation provided further understanding of LED device temperature distribution and also revealed that the thermal variance at the die-attached interface can be recognized within only few milliseconds for the flip chip structure. The effects of bump arrangement and material were analyzed to achieve high temperature uniformity and low thermal resistance for high power LEDs.
Autologous transfusion in cardiac surgery: a case report of a patient with a rare antibody.

Open heart operations are sometimes performed without donor blood because of religious beliefs of the patient. A medical reason for performing surgery without donor blood occurs when the patient has an antibody to which no available donor blood is compatible. In the case reported, two units of blood were removed from the patient during a 48-hour period prior to an aortic valve replacement. These were transfused to him postoperatively with good results.
Statistics of gamma-ray bursts - Homogeneous spherical models

Early reports from the BATSE experiment seem to suggest that the observed gamma-ray bursts occur in a highly flattened region of space. This inference, however, is contradicted by the apparent isotropy of the bursts. Here, it is demonstrated that this apparent dilemma can be resolved in a straightforward manner if bursts occur in a bounded spherical volume centered about the observer. Such a geometrical distribution of the bursts can be consistent with the apparent isotropy of the bursts. Two different models in which the burst population is uniformly distributed in a bounded spherical region of space are considered.
Cotton benzoquinone reductase: up-regulation during early fiber development and heterologous expression and characterization in Pichia pastoris.

Abstract Benzoquinone reductase (BR; EC 1.6.5.7) is an enzyme which catalyzes the bivalent redox reactions of quinones without the production of free radical intermediates. Using 2D-PAGE comparisons, two proteins were found to be up-regulated in wild-type cotton ovules during the fiber initiation stage but not in the fiberless line SL 1-7-1. These proteins were excised from the gel, partially sequenced and identified to be BR isoforms. PCR was used to amplify both full length coding regions of 609 bp and once cloned, the restriction enzyme HindIII was used to distinguish the clones encoding the BR1 (one site) and BR2 (two sites) isoforms. Both deduced protein sequences had 203 residues which differed at 14 residues. The molecular mass and pIs were similar between the measured protein (2D-PAGE) and the theoretical protein (deduced). Heterologous proteins BR1 and BR2 were produced for further study by ligating the BR1 and BR2 clones in frame into the α-factor secretion sequence in pPICZαA vector and expressed with Pichia pastoris. Both BR1 and BR2 were approximately 26.5 kDa and did enzymatically reduce 2,6-dimethoxybenzoquinone similar to the fungal BR.
Serotonin sensitive adenylate cyclase activity in monkey anterior limbic cortex: antagonism by molindone and other antipsychotic drugs.

Abstract Serotonin (5-HT) sensitive adenylate cyclase in monkey anterior limbic cortex homogenates was further characterized and the effects of antipsychotic drugs and 5-HT anatagonists investigated. Differences in time course for stimulation by agonists and in responsiveness to receptor anatagonists of 5-HT-and dopamine (DA)-stimulated activities, were observed. Also there was an additivity of 5-HT and DA at maximally effective concentrations. Classical 5-HT antagonists blocked the 5-HT sensitive adenylate cyclase with a rank order of potency: methiothepin > cyproheptadine > methysergide. These 5-HT antagonists also effectively inhibited DA sensitive adenylate cyclase. Most antipsychotic drugs tested antagonized 5-HT stimulated activity although these drugs exhibited greater efficacies in blocking DA stimulated activity. Exceptions were molindone which failed to antagonize DA sensitive adenylate cyclase but effectively blocked 5-HT sensitive cyclase and pipamperone which was inactive in both cyclase systems. Haloperidol was a more selective antagonist of the DA sensitive adenylate cyclase than were the other antipsychotic drugs tested.
Initiation and resolution of mucosal inflammation

Antigens entering the body through the mucosal surface are screened by a highly developed immune system comprised not only of traditional lymphoid cells but also epithelial cells, fibroblasts, and antigen-presenting cells (APCs). For example, in the intestinal tract, gut-associated lymphoid tissue (GALT) is tolerant to the approx 400 separate commensal strains residing mainly in the colon, but also retains the capacity to detect and remove virulent bacteria before they infect systemically. This review summarizes recent work characterizing the molecular mechanisms involved in acute and chronic intestinal inflammation. We will also describe a natural murine pathogen, Citrobacter rodentium, which is being used to explore the host response to enteric pathogens and the resulting immunopathology.
On sums of $\mathit{SL}(3,\mathbb{Z})$ Kloosterman sums

We show that sums of the $\mathit{SL}(3,\mathbb{Z})$ long element Kloosterman sum against a smooth weight function have cancelation due to the variation in argument of the Kloosterman sums, when each modulus is at least the square root of the other. Our main tool is Li’s generalization of the Kuznetsov formula on $\mathit{SL}(3,\mathbb{R})$ , which has to date been prohibitively difficult to apply. We first obtain analytic expressions for the weight functions on the Kloosterman sum side by converting them to Mellin–Barnes integral form. This allows us to relax the conditions on the test function and to produce a partial inversion formula suitable for studying sums of the long-element $\mathit{SL}(3,\mathbb{Z})$ Kloosterman sums.
Causes and Consequences of Invasive Plants in Wetlands: Opportunities, Opportunists, and Outcomes

Wetlands seem to be especially vulnerable to invasions. Even though ≤6% of the earth's land mass is wetland, 24% (8 of 33) of the world's most invasive plants are wetland species. Furthermore, many wetland invaders form monotypes, which alter habitat structure, lower biodiversity (both number and “quality” of species), change nutrient cycling and productivity (often increasing it), and modify food webs. Wetlands are landscape sinks, which accumulate debris, sediments, water, and nutrients, all of which facilitate invasions by creating canopy gaps or accelerating the growth of opportunistic plant species. These and other disturbances to wetlands, such as propagule influx, salt influx, and hydroperiod alteration, create opportunities that are well matched by wetland opportunists. No single hypothesis or plant attribute explains all wetland invasions, but the propensity for wetlands to become dominated by invasive monotypes is arguably an effect of the cumulative impacts associated with landscape sinks, incl...
On free alternative rings

Abstract An example is presented that ansevers in the negative the question of whether the square of every commutator need always lie in the nucleus. Also, we show the existence of specific nilpotent elements in the free alternative ring on four or more generators, and prove abstractly the existence of an ideal I≠0, and I2=0.
Calcium physiology in smooth muscle

Abstract The intracellular Ca ++ concentration in smooth muscle is maintained at a concentration lower than 10 −7 M via active extrusion against an electrochemical gradient across an essentially impermeable plasma membrane. With receptor activation and/or membrane depolarization, the Ca ++ permeability of the membrane is increased, and Ca ++ flows into the cell. Additionally, Ca ++ is relased from intracellular stores, further contributing to the increase in the cytoplasmic Ca ++ concentration. As the intracellular Ca ++ concentration rises above 10 −6 M , Ca ++ binds to calmodulin, which then forms a complex with myosin kinase. This enzyme complex phosphorylates the 20,000 MW light chain of myosin, activating the myosin and allowing myosin and actin to cyclically hydrolyze ATP. As a result of their intracellular arrangement, the actin and myosin filaments slide past each other, causing contraction. Relaxation occurs as the cytoplasmic Ca ++ concentration is again lowered through a combination processes including: (1) membrane repolarization with resultant closure of calcium channels and unopposed extracellular extrusion of Ca ++ ; and (2) intracellular sequestration of Ca ++ by the sarcoplasmic reticulum and possibly mitochondria. This latter process may also be stimulated by increases in intracellular cyclic AMP levels as well as by direct and receptor mediated effects of other pharmacologic agents. The Ca ++ which is taken up by the sarcoplasmic reticulum may be subsequently released into the extracellular fluid via couplings between the sarcosplasmic reticulum and the plasma membrane. The fall in the cytoplasmic Ca ++ concentration allows Ca ++ -independent dephosphorylation of myosin to proceed unopposed, leading in turn to inactivation of the myosin, decreased actin-myosin interaction, and relaxation. The mechanisms by which the cytoplasmic Ca ++ concentration is raised or lowered are represented diagramatically in Figs. 7 and 8.
Measurements of outflow from the base of solar coronal holes

New evidence is presented that EUV emission lines formed at the levels of the base of the corona and the transition region are systematically shifted to shorter wavelengths within coronal holes relative to the rest of the solar disk, and that moreover this shift increases with height in the atmosphere. Measurements were made with a rocket-borne EUV spectrometer having high spectroscopic resolution and stability flown on July 15, 1980. Repeated measurements were made along a chord of the solar disk that crossed a compact coronal hole near sun center identified on gamma 10830 He I spectroheliograms. The maximum measured shift corresponded to a velocity of 12 km/sec in gamma 625 Mg X and 7 km/sec in gamma 629 O V. If these velocities correspond to a true mass flux, they provide important data on the acceleration of coronal plasma in open magnetic field regions. These observed Doppler displacements are a strong and significant signature of coronal holes, now measured on three rocket flights.
The thermodynamics of synergistic solvent extraction of zinc(II)

Abstract The thermodynamics of the synergistic solvent extraction of zinc(II) by HTTA-TBP mixtures were studied using radiochemical techniques. The thermodynamic values of the extraction equations indicate that the mechanism of adduct formation by TBP with the Zn(TTA) 2 chelate involves expansion of the coordination number of the central metal ion from 4 to 5. The extraction of zinc(II) by HDEHP-TBP mixtures was also studied but no synergistic effect was seen in this extraction system.
Cuba en la comunidad internacional en los noventa : soberanía, derechos humanos y democracia

Luego de gobernar Cuba por mas de un tercio de siglo, en los primeros anos del decenio de 1990 el principal logro de Castro que aun permanece es haber construido la soberania de Cuba. Su aseveracion de que mantuvo la bandera de la nacion en . alto en actitud digna y desafiante contra todas las dificultades sigue siendo la base de su fuerza y atractivo politicos. Es el instrumento mediante el cual espera unir a los cubanos para que apoyen a su gobierno en el momento de mayor peligro. Perdidas entre los escombros del derrumbe de la Union Sovietica se encuentran otras reivindicaciones de trascendencia que Castro podria haber realizado a mediados del decenio de 1980. Los economistas cubanos han calculado que el Producto Social Global (PSG) de la nacion -la medida mas amplia del desempeno de la economia cubanacayo un tanto durante la segunda mitad de los anos ochenta y luego bajo en forma catastrofica a comienzos de los anos noventa. En especial, Julio Carranza ha estimado que en 1990 el PSG de Cuba disminuyo 3.6%, en terminos reales, 24% en 1991, y alrededor de 15% en 1992.1 Como resultado de esta desmedrada situacion economica, los logros mas preciados del gobierno cubano -sus realizaciones en materia de salud y educacionse vieron empanados hasta hacerse irreconocibles. Comenzaron a escasear los libros de texto y los medicamentos se volvieron insuficientes; en 1993, sobrevino una grave epidemia que afectaba los ojos y las extremidades de las personas. La nacion confia en que todo esto terminara y espera un milagro. No obstante, a comienzos de los anos noventa, la construccion de la soberania de Cuba siguio siendo un logro de especial significado para los adultos de entre aproximadamente 40 y 70 anos. Algunos de
Limitations of an oscillometricambulatory blood pressure monitor in physically active children

Objective : To determine the limitations of an oscillometric device for measuring ambulatory blood pressure in physically active children. Design : Observational descriptive. Subjects : Sixty-one children 4.3 to 18.7 years of age. Interventions : Twenty-two high school students wore an ambulatory blood pressure monitor (Spacelabs model 90202) for 24 hours. A subject-kept activity diary facilitated data interpretation. In 39 additional subjects, measurements were recorded during strenuous exercise, at rest, and after ambulation. Before and after the students wore the unit, oscillometric and auscuitatory blood pressure measurements were simultaneously taken to callbrate the ambulatory blood pressure monltor, evaluate its accuracy, and assess deterioration in the calibration of the unit with use. Results : During 24-hour ambulatory monitoring, 29% of the readings were edited-because of error codes, primarily because of vibratory interference. At the end of the 24-hour monitoring period, simultaneous pressures by oscillometric and auscultatory techniques agreed within 6 mm Hg in 17 of 18 cases for both systolic and diastolic blood pressures. During exercise, 88.4% of the systolic and diastolic blood pressure readings agreed within 8 mm Hg. In 20 other ambulatory subjects with 80 simultaneous oscillometric and auscultatory measurements, all systolic and 88.5% of the diastolic values agreed within 10%. Conclusions : These results Indicate that the SpaceLabs model 90202 unitprovides a reasonably accurate assessment of ambulatory blood pressures in mildly active and inactive children and that blood pressure can be monitored with time.
Visual-spatial abilities relate to mathematics achievement in children with heavy prenatal alcohol exposure.

Objective The current study examined the relationship between mathematics and attention, working memory, and visual memory in children with heavy prenatal alcohol exposure and controls. Method Subjects were 56 children (29 AE, 27 CON) who were administered measures of global mathematics achievement (WRAT-3 Arithmetic & WISC-III Written Arithmetic), attention, (WISC-III Digit Span forward and Spatial Span forward), working memory (WISC-III Digit Span backward and Spatial Span backward), and visual memory (CANTAB Spatial Recognition Memory and Pattern Recognition Memory). The contribution of cognitive domains to mathematics achievement was analyzed using linear regression techniques. Attention, working memory, and visual memory data were entered together on Step 1 followed by group on Step 2, and the interaction terms on Step 3. Results Model 1 accounted for a significant amount of variance in both mathematics achievement measures; however, model fit improved with the addition of group on Step 2. Significant predictors of mathematics achievement were Spatial Span forward and backward and Spatial Recognition Memory. Conclusions These findings suggest that deficits in spatial processing may be related to math impairments seen in FASD. In addition, prenatal alcohol exposure was associated with deficits in mathematics achievement, above and beyond the contribution of general cognitive abilities.
Mesh Network Applications in First Respond Service, Case Study: Policy Simulation

The advantages of mesh network provide huge potential for its application in transportation network security and first response service. The application of mesh network in transportation security will not only improve emergency response, but also help the coordination and integration across agencies, regions, and public safety and transportation disciplines. The goal of this paper is to explore the potential applications of mesh network in emergency response service and to analyze the performance of various emergency dispatching policies using simulations. The case study shows that with help of mesh network and integrated management, promising savings in average response time and reduction in the percentage of long response times can be achieved.
Positive and negative liquid secondary ion mass spectrometry of chloro- and nitrophenylglucuronides

Mass spectra of a series of chloro- and nitrophenylglucuronides by liquid secondary ion (LSI) mass spectrometry were obtained. In the positive ion mode class characteristic fragmentations and adduct ions are observed only in the presence of alkali salt additives. No additives were necessary in the negative ion mode to see abundant class characteristic [M-H]- and aglycone fragment ions. Cluster ion formation was found to be prominent but only in the negative ion mode.
Inhibition of Alzheimer's Amyloidosis by Peptides That Prevent β-Sheet Conformation

Abstract Amyloid β-peptide (Aβ) is a major fibrillar component of neuritic plaques in Alzheimer's disease (AD) brains and is related to the pathogenesis of the disease. We hypothesized that amyloid formation could be inhibited by peptides homologous to Aβ (position 17-21) with a similar degree of hydrophobicity, but with a very low propensity to adopt a β-sheet conformation by incorporating proline residues (anti-β-sheet peptides or β-sheet inhibitors). An 11-residue peptide with these characteristics binds to Aβ, inhibits Aβ fibril formation and partially disaggregates preformed fibrils in vitro. Shorter anti-β-sheet peptides and analogs containing D-amino acids are also able to inhibit Aβ fibrillogenesis. The latter are more resistant to proteolytic degradation and may serve as a starting point to design more efficient peptides derivatives to inhibit amyloidogenesis in vivo.
Exploring unexplained variation

In a 1974 commencement address, Richard Feynman described scientific integrity as a kind of utter honesty, a kind of leaning over backwards to tell the whole truth. We argue that investigators could tell more of the truth and increase the value of their papers by highlighting and discussing unexplained variation, a major source of which is individual differences. An argument that unexplained individual differences must have many sources is presented, and means of representing that variation are illustrated. We believe that such a change in reporting of research results is likely to advance the progress of scientific psychology, but perhaps the most compelling argument for what we propose is simply that telling the whole story as fully as possible is good scientific practice. The Appendix provides two examples of what we are urging, taken from recent psychological literature.
Henry's law and synergism in dilute near‐critical solutions: Theory and simulation

An asymptotic analysis based on Taylor series expansions is used for first-order correction terms to the Henry's law approximation to describe solvation phenomena in multiple solute-multiple solvent systems. The magnitude of these correction terms in solvent systems very near their critical points is of particular concern, as shown in model fluid calculations with the aid of integral equation theory. The results clearly demonstrate that close proximity to the critical point in pure and mixed solvent systems causes the Henry's law approximation to show large errors in predicting solubilities, especially near the critical azeotrope of a mixed solvent system. Theoretical results also show that cross solubility enhancements in a two solutesupercritical solvent system cause cooperative synergism (both solute solubilities are increased relative to the corresponding single solute situations) or reverse synergism (both depressed relative to the single solute situation). It appears to be consistent with the available data. In computer simulations, the solute's infinitely dilute reference state is often used as a basis for describing solute thermodynamic behavior. These simulations are best achieved in the canonical ensemble because of the weak composition dependence of free energies in terms of characteristic variables of this ensemble.