cssi/SciSciGPT-SciSciNet huggingface dataset:
Effect of Loading Rate and Surface Conditions on the Flexural Strength of Borosilicate Glass

This study evaluates the loading rate and surface condition dependence of the flexural strength of a borosilicate glass. The glass specimens are subjected to three different surface treatments before four-point bending tests to study the effect of surface flaws. Quasistatic (Material Test System 810) and dynamic (Kolsky bar) experiments are performed at loading rates ranging from 0.7 to 4 x 10{sup 6} MPa/s. The results show that the flexural strength of the borosilicate glass has a strong dependence on the loading rate. A chemically etched surface produces an enhanced flexural strength by about an order of magnitude. Scanning electron microscopy images on fracture surfaces indicate that the failure is governed by different types of flaws under different surface treatment conditions. Edge failure is also identified for samples possessing high flexural strength.
Full-length Ebola glycoprotein accumulates in the endoplasmic reticulum

The Filoviridae family comprises of Ebola and Marburg viruses, which are known to cause lethal hemorrhagic fever. However, there is no effective anti-viral therapy or licensed vaccines currently available for these human pathogens. The envelope glycoprotein (GP) of Ebola virus, which mediates entry into target cells, is cytotoxic and this effect maps to a highly glycosylated mucin-like region in the surface subunit of GP (GP1). However, the mechanism underlying this cytotoxic property of GP is unknown. To gain insight into the basis of this GP-induced cytotoxicity, HEK293T cells were transiently transfected with full-length and mucin-deleted (Δmucin) Ebola GP plasmids and GP localization was examined relative to the nucleus, endoplasmic reticulum (ER), Golgi, early and late endosomes using deconvolution fluorescent microscopy. Full-length Ebola GP was observed to accumulate in the ER. In contrast, GPΔmucin was uniformly expressed throughout the cell and did not localize in the ER. The Ebola major matrix protein VP40 was also co-expressed with GP to investigate its influence on GP localization. GP and VP40 co-expression did not alter GP localization to the ER. Also, when VP40 was co-expressed with the nucleoprotein (NP), it localized to the plasma membrane while NP accumulated in distinct cytoplasmic structures lined with vimentin. These latter structures are consistent with aggresomes and may serve as assembly sites for filoviral nucleocapsids. Collectively, these data suggest that full-length GP, but not GPΔmucin, accumulates in the ER in close proximity to the nuclear membrane, which may underscore its cytotoxic property.
Induced magnetization density in the 5f system UAl2

Using a polarized‐neutron diffractometer we have studied the induced magnetization density in the unit cell of the 5f system UAl2. Measurements have been made on single crystals at 4.2 K with an applied magnetic field of 42.5 kOe (induced magnetic moment 0.0344 μB per mole). Neutron wavelengths of 1.067 and 0.785 A and different crystal thicknesses have been used to correct for and eliminate any effects from extinction. The major part of the magnetization density appears as a contribution localized at the U site, exhibiting a form factor similar to that of the f3 free ion, and extrapolating in the forward direction to the value given by the bulk susceptibility. However, there are two interesting aspects of the density. First, the form factor points differs significantly from a smooth curve. This indicates asphericity in the 5f electron distribution arising from the crystalline environment of the U atoms. Second, and more unusual, finite magnetic scattering amplitudes have been observed for a series of reflections to which the centrosymmetric density at the U site cannot contribute. We consider this as strong evidence of noncentrosymmetric bonding involving the 5f–6d electrons.
The Spatial and Temporal Evolution of a Cluster of SOFAR Floats in the POLYMODE Local Dynamics Experiment (LDE)

Abstract Up to forty neutrally buoyant floats (20 at 700 m, 20 at 1300 m) were used in the POLYMODE Local Dynamics Experiment (LDE) to provide a quasi-Lagrangian description of the structure and evolution of the mesoscale eddy field in a limited region characterized by higher kinetic energy levels than those obtained in MODE. This paper is an overview and summary of the data collected. The temporal development of the two-level float array is presented in a sequence of maps, each spanning five days. In these one readily notices an “oscillation” of floats at 1300 m in a NE-SW direction before the cluster breaks apart. At 700 m the float cluster subdivides much more rapidly. The first setting of 700-m floats drifts to the west; the second group, launched two months later, goes far to the east. Ensemble averages as a function of time of the floats at 1300 m reveal great sensitivity to the “oscillatory” velocity field while the array is “tight” or coherent the corresponding 700-in averages, although noisy, sho...
Half-Heusler phases and nanocomposites as emerging high-ZT thermoelectric materials

Half-Heusler (HH) phases, a versatile class of alloys with promising functional properties, have recently gained attention as emerging thermoelectric materials. These materials are investigated from the perspective of thermal and electronic transport properties for enhancing the dimensionless figure of merit (ZT) at 800–1000 K. The electronic origin of thermopower enhancement is reviewed. Grain refinement and embedment of nanoparticles in HH alloy hosts were used to produce fine-grained as well as nanocomposites and monolithic nanostructured materials. Present experiments indicated that n-type Hf0.6Zr0.4NiSn0.995Sb0.005 HH alloys and p-type Hf0.3Zr0.7CoSn0.3Sb0.7/nano-ZrO2 composites can attain ZT = 1.05 and 0.8 near 900–1000 K, respectively. The observed ZT enhancements could be attributed to multiple origins; in particular, the electronic origin was identified. The prospect for higher ZT was investigated in light of a recently developed nanostructure model of lattice thermal conductivity. Tests performed on p–n couple devices from the newly developed HH materials showed good power generation efficiencies—achieving 8.7% efficiency for hot-side temperatures of about 700 °C.
Effective Multi-Model Motion Tracking using Action Models

We consider tasks where robots act on the target that is visually tracked, such as kicking a ball or pushing an object. We introduce a principled approach to incorporate models of the robot-object interaction into the tracking algorithm to effectively improve the performance of the tracker. We first present the integration of a single robot behavioral model with multiple actions into our dynamic Bayesian probabilistic tracking algorithm. We then extend to multiple motion tracking models corresponding to known multi-robot coordination plans or from multi-robot communication. We evaluate our resulting informed-tracking approach empirically in simulation and using a setup Segway robot soccer task. The input of the multiple single and multi-robot behavioral models allows a robot to visually track mobile targets with dynamic trajectories more effectively.
Heat and mass transfer in wood during drying

Abstract A model for heat and mass transport in softwood is developed. The model includes liquid transport via capillary action as well as diffusion. The model is unique in that transport properties which in some cases are both not available in the literature and difficult to measure are developed from knowledge of wood structure. Calculated results compared favorably with those determined experimentally. The experimental results represent the first of their kind in that moisture profiles are measured during the drying process using gamma attenuation.
Geochemical Comparison of Ground Water in Areas of New England, New York, and Pennsylvania

The ground-water geochemistry of glacial drift and bedrock of selected areas of New England, New York, and Pennsylvania differs considerably among the areas as a result of differences in bedrock geology. The New England study area is underlain primarily by feldspathic rock, large areas of New York are underlain primarily by carbonate and terrigenous sedimentary rock and some evaporite deposits, and glaciated areas of Pennsylvania are underlain primarily by clastic sedimentary rock with minor carbonate rocks. Mean concentrations of most solutes are greatest in the New York area and least in the New England area. In New England, the ground-water geochemistry results mainly from the reaction of CO2-charged water with feldspar and other primary silicates. Water in the New England bedrock is more highly evolved geochemically than water in the drift, presumably as a result of its longer residence time. In the New York area, the geochemistry of water in both types of aquifers results mainly from carbonate- mineral dissolution. Water in most glacial drift and bedrock is saturated with respect to calcite. In some parts of New York, the dissolution of evaporite minerals has a marked effect on the water chemistry of the bedrock. In most of the Pennsylvania area, the geochemistry of water in both types of aquifers indicates that, although carbonate minerals are the principal reactants, their influence on water chemistry is less than in New York. In parts of Pennsylvania, chemical differences between ground water from drift and ground water from bedrock are attributed to a higher proportion of reactive minerals in the drift than in the local bedrock as a result of glacial transport.
Volatile memristive devices as short-term memory in a neuromorphic learning architecture

Image classification with feed-forward neural networks typically assumes the application of input images as single column vectors, which leads to a large number of required input neurons as well as large synaptic arrays connecting individual neural layers. In this paper we show how a class of memristive devices can be used as non-linear, leaky integrators that extend regular feed-forward neural networks with short-term memory. By trading space for time, our novel architecture allows to reduce the number of neurons by a factor of 3 and the number of synapses up to 15 times on the MNIST data set compared to previously reported results. Furthermore, the results indicate that less neurons and synapses also leads to a reduced learning complexity. With memristive devices functioning as dynamic processing elements, our findings advocate for a diverse use of memristive devices that would allow to build more area-efficient hardware by exploiting more than just their non-volatile memory property.
Inhibition of UV-induced DNA strand breakage in Dictyostelium discoideum by 2,4-dinitrophenol.

— In UV-irradiated vegetative cultures of the cellular slime mold Dictyostelium discoideum NC-4, single strand breaks appeared in the DNA very rapidly and at low temperatures (0–4°C). However, when these cells were incubated, prior to UV irradiation, in the presence of 2 mM 2,4-dinitrophenol (DNP), an uncoupler of oxidative phosphorylation, breaks did not appear in the DNA. Extracts prepared from cells that had been incubated either in the presence or absence of DNP were tested for endonucleolytic activities on a UV-irradiated exogenous DNA template (φX-174 RF I). Results suggested that DNP might mediate its effect by interfering with the action of a UV-specific endonuclease.
Formation, transport, and storage of ribonucleic acid containing structures in oocytes of Acheta domesticus (Orthoptera).

Oocyte development of Acheta domesticus was investigated morphologically and cytochemically. The studies demonstrated a size decrease and final disappearance of a large extrachromosomal DNA body in the nuclei as the cells proceeded through the diplotene stage of meiosis. The body was surrounded by fascicles of RNA containing material. This material remained within the nuclei in individual packets after the DNA body was no longer detectable. An active nucleo-cytoplasmic migration of RNA was seen prior to the disappearance of the DNA body. After the disappearance of the body very little migration was detected. Evidence was presented to demonstrate the ribosomal nature of this migratory RNA. The RNA packets remaining in nuclei of cells arrested in the diplotene stage of oogenesis functioned as storage depots for ribosomal RNA.
How many pixels make an image

The human visual system is remarkably tolerant to degradation in image resolution: human performance in scene categorization remains high no matter whether low-resolution images or multimegapixel images are used. This observation raises the question of how many pixels are required to form a meaningful representation of an image and identify the objects it contains. In this article, we show that very small thumbnail images at the spatial resolution of 32 × 32 color pixels provide enough information to identify the semantic category of real-world scenes. Most strikingly, this low resolution permits observers to report, with 80% accuracy, four to five of the objects that the scene contains, despite the fact that some of these objects are unrecognizable in isolation. The robustness of the information available at very low resolution for describing semantic content of natural images could be an important asset to explain the speed and efficiently at which the human brain comprehends the gist of visual scenes.
Is Oxidant Stress a Connection Between Obesity and Atherosclerosis

The marked increase in the incidence of overweight and obese persons is recognized as one of the most serious public health issues in the United States. It is estimated that currently >60% of American adults are overweight and 20% are obese.1 Overweight and obesity are associated with a significantly increased mortality from atherosclerotic cardiovascular disease and other causes.2–4⇓⇓ Although obesity itself appears to augment the incidence of cardiovascular events, it is also associated with major risk factors for atherosclerosis including hyperlipidemia, diabetes mellitus, hypertension, and the metabolic syndrome.1,5⇓ How obesity and each of these risk factors are involved mechanistically in atherosclerosis have been areas of intense research but are poorly understood. A panel of experts assembled by the National Institutes of Health recently concluded that the study of mechanisms by which obesity contributes to atherosclerosis should be a high priority.1 The report by Keaney et al6 in this issue of Arteriosclerosis, Thrombosis, and Vascular Biology provides evidence that increased systemic oxidant stress may be an important mechanism by which obesity increases the incidence of atherosclerotic cardiovascular disease. See pages 365 and 434 Enhanced oxidant stress, occurring either locally in the arterial wall or systemically, is one hypothesis to explain the development and progression of atherosclerosis in humans.7–9⇓⇓ In particular, oxidative modification of the lipid components of LDL has been hypothesized as causative. LDL is deposited in the vascular wall early in the course of atherosclerotic lesion development where it is oxidized.10 There is evidence both in vitro and in animal models of human atherosclerosis that oxidized lipids derived from LDL contribute to many of the stages …
A fully monolithic 260-/spl mu/W, 1-GHz subthreshold low noise amplifier

A micro-power complementary metal oxide semiconductor (CMOS) low-noise amplifier (LNA) is presented based on subthreshold MOS operation in the GHz range. The LNA is fabricated in an 0.18-/spl mu/m CMOS process and has a gain of 13.6 dB at 1 GHz while drawing 260 /spl mu/A from a 1-V supply. An unrestrained bias technique, that automatically increases bias currents at high input power levels, is used to raise the input P1dB to -0.2 dBm. The LNA has a measured noise figure of 4.6 dB and an IIP3 of 7.2 dBm.
AFTRA and contract negotiations

Probably the most widespread of the unions representing the employees, of broadcasting stations is AFTRA, which serves the interests of announcers, actors, and other on‐mike and on‐camera performers in thousands of stations and other production units. The following article details the complicated process of negotiating contracts between union and employer groups as practiced by AFTRA. It should be of special interest to the management of radio and television stations, particularly those stations employing AFTRA members.
Pharmacokinetics and Short-Term Safety of 873140, a Novel CCR5 Antagonist, in Healthy Adult Subjects

873140 is a novel CCR5 antagonist with potent in vitro anti-human immunodeficiency virus (HIV) activity. This study was a double-blind, randomized, placebo-controlled, single- and repeat-dose escalation investigation of the safety, pharmacokinetics, and food effect of 873140 in 70 adult subjects. During single-dose escalation, three cohorts (each composed of 10 subjects, with 8 subjects receiving the active drug and 2 subjects receiving the placebo [8 active and 2 placebo]) received doses of 50, 200, 400, 800, and 1,200 mg after an overnight fast, or 400 mg plus a standard high-fat breakfast in an alternating panel design. During repeat-dose escalation, four cohorts (each with 8 active and 2 placebo) received doses of 200, 400, 600, or 800 mg every 12 h (BID) for 8 days. Laboratory safety tests, vital signs, and electrocardiograms (ECGs) were performed at regular intervals, and blood samples were obtained for pharmacokinetics. Single and repeat doses of 50 mg to 800 mg were well tolerated, with no serious adverse events and no grade 3 or 4 adverse events. The mild-tomoderate side effects were primarily gastrointestinal and included abdominal cramping, nausea, and diarrhea. No specific trends in laboratory parameters or clinically significant ECG changes were noted. Plasma 873140 concentrations increased rapidly; the median time to maximum concentration of drug in serum was 1.75 to 5 h. The median area under the plasma concentration-time profile (AUC) and the maximum concentration of drug in serum (Cmax) ranged from 127 ng · h/ml and 24 ng/ml at 200 mg BID to 329 ng · h/ml and 100 ng/ml at 800 mg BID, respectively. Food consumption increased the AUC and Cmax by a mean of 1.7- and 2.2-fold, respectively. The pharmacokinetic and safety profile supports the continued investigation of 873140 with HIV-infected subjects. Despite an improvement in morbidity and mortality attributable to highly active antiretroviral therapy (HAART), the emergence of multiclass drug-resistant strains and the problematic toxicities associated with HAART warrant the development of new classes of therapies for human immunodeficiency virus (HIV) infection. Most of the currently approved antiretroviral drugs are targeted toward the inhibition of viral enzymes. The identification of the HIV coreceptors CC chemokine receptor 5 (CCR5) and CXC chemokine receptor 4 (CXCR4) on the cell surface has resulted in an improved understanding of viral entry and fusion. These discoveries have led to promising new targets for drug development (7).
Small molecule inhibitors of the annexin A2 heterotetramer prevent human papillomavirus type 16 infection

Objectives High-risk human papillomavirus (HPV) infection leads to the development of several human cancers that cause significant morbidity and mortality worldwide. HPV type 16 (HPV16) is the most common of the cancer-causing genotypes and gains entry to the basal cells of the epithelium through a non-canonical endocytic pathway that involves the annexin A2/S100A10 heterotetramer (A2t). A2t is composed of two annexin A2 monomers bound to an S100A10 dimer and this interaction is a potential target to block HPV16 infection. Here, recently identified small molecule inhibitors of A2t (A2ti) were investigated for their ability to prevent HPV16 infection in vitro.
Limitations of regulated "buffer zones" for the conservation of marbled salamanders

Most amphibians that breed in seasonal wetlands are predominantly terrestrial animals that require “upland” habitats for the majority of their life cycles. However, wetland regulations aimed partially at protecting wildlife values are often limited to the wetland basins and small terrestrial “buffer zones” that typically extend 30 m or less from the wetland edge. In this study, we assessed whether a common buffer zone (i.e., 30 m) is sufficient for the conservation of marbled salamanders (Ambystoma opacum). We installed and monitored two concentric and continuous drift fence arrays (3 m and 30 m from the pond margin) around each of three seasonal ponds in western Massachusetts, USA. We quantified the numbers and percentages of breeding adults and emerging juvenile salamanders that immigrated from and/or emigrated beyond the 30-m fences. In addition, we recorded incidental year-of-emergence captures of juveniles at more distant drift fences that were in place for a broader study. Of the breeding adults captured immigrating to the basins at 3-m fences, 84–96% were first captured at 30-m fences, and corrections for capture probabilities suggested that nearly 100% of these individuals originated beyond 30 m from their breeding sites. Of the newly emerging juveniles captured emigrating from the basins at 3-m fences, 58–85% were subsequently captured at 30-m fences and 284 juvenile captures were recorded at distances between 111 and 1,230 m (median = 269.2 m) from natal ponds. Our findings highlight the dramatic limitations of existing wetland regulations with regard to upland habitat use by mole salamanders (family Ambystomatidae) and the need to approach conservation of these animals both at broader scales and with more comprehensive and innovative strategies.
Severe Opportunistic Infections In AIDS Patients With Late-Stage Disease

BACKGROUND Clinicians caring for patients who have acquired immunodeficiency syndrome (AIDS) need to be aware of the wide variety of infectious diseases that can occur. Although Pneumocystis carinii pneumonia (PCP) is the most common AIDS-defining infection, other opportunistic infections associated with advanced immunodeficiency can develop after an initial diagnosis. METHODS To ascertain AIDS-defining opportunistic infections that developed at the time of or after an AIDS diagnosis, and intensive chart review was conducted for 45 homosexual men with AIDS who died from 1990 through 1992. Time to death after first occurrence of these infections was also determined. RESULTS The most common opportunistic infection occurring as the initial AIDS-defining illness was PCP (31 percent). The most common opportunistic infection occurring as a secondary disease was cytomegalovirus (CMV) disease (40 percent), followed by disseminated Mycobacterium avium complex (33 percent) and invasive candidiasis (31 percent). Each of these latter infections was associated with a poor prognosis (median time to death < or = 8 months). CONCLUSIONS Diseases caused by CMV, disseminated M. avium complex, and invasive candidiasis were uncommon presenting manifestations of AIDS but were common secondary diseases that tended to be associated with limited survival. With increasing survival and a declining incidence of PCP as a result of medical therapy, other severe opportunistic infections might become increasingly recognized.
Modeling and Analysis of Probabilistic Timed Systems

Probabilistic models are useful for analyzing systems which operate under the presence of uncertainty. In this paper, we present a technique for verifying safety and liveness properties for probabilistic timed automata. The proposed technique is an extension of a technique used to verify stochastic hybrid automata using an approximation with Markov Decision Processes. A case study for CSMA/CD protocol has been used to show case the methodology used in our technique.
BLACKER: security for the DDN examples of A1 security engineering trades

BLACKER is the name given by the US Department of Defense (DoD) to a long-term project to build an integrated suite of devices to secure the US Defense Data Network (DDN). There are four devices which together provide a secure system applique to DDN designed to achieve A1 security certification. The issues reported fall into two groups: A1 security techniques and A1 program management. The first group looks at engineering techniques to gain certification. The issues deal with INFOSEC, the combination of COMSEC and (communications security) and COMPUSEC (computer security), techniques, that were successfully integrated in BLACKER. The second group looks at some key programmatic issues of success. The lessons learned and the technology obtained can be applied in other programs. >
Feature-aided localization and tracking of ground vehicles using passive acoustic sensor networks

Tracking of a moving ground target using acoustic signals obtained from a passive sensor network is a difficult problem as the signals are contaminated by wind noise and are hampered by road conditions, terrain and multipath, etc., and are not deterministic. Multiple target tracking becomes even more challenging, especially when some of the vehicles are light (wheeled) and some are heavy (e.g., tracked vehicles like tanks). In such cases the stronger acoustic signals from the heavy vehicles can mask those from the light vehicles, leading to poor detection of such targets. Acoustic passive sensor arrays obtain direction of arrival (DoA) angle estimates of such emitters from the received signals. The full position estimates of targets, obtained following the association of the DoA angle estimates from least three sensor arrays, are used for target tracking. However, because of the particular challenges encountered in multiple ground vehicle tracking, this association is not always reliable and thus, target tracking using such full position measurements only is difficult and it can lead to lost tracks. In this paper we propose a new feature-aided tracking (FAT) algorithm to augment the existing target tracking algorithms which use only kinematic measurements, in order to improve the tracking performance. We present a novel DoA detection technique followed by frequency domain feature extraction from real data. The techniques are developed based on real data sets and tested on real data based on a field experiment.
EAD and PEBD: Two Energy-Aware Duplication Scheduling Algorithms for Parallel Tasks on Homogeneous Clusters

High-performance clusters have been widely deployed to solve challenging and rigorous scientific and engineering tasks. On one hand, high performance is certainly an important consideration in designing clusters to run parallel applications. On the other hand, the ever increasing energy cost requires us to effectively conserve energy in clusters. To achieve the goal of optimizing both performance and energy efficiency in clusters, in this paper, we propose two energy-efficient duplication-based scheduling algorithms-Energy-Aware Duplication (EAD) scheduling and Performance-Energy Balanced Duplication (PEBD) scheduling. Existing duplication-based scheduling algorithms replicate all possible tasks to shorten schedule length without reducing energy consumption caused by duplication. Our algorithms, in contrast, strive to balance schedule lengths and energy savings by judiciously replicating predecessors of a task if the duplication can aid in performance without degrading energy efficiency. To illustrate the effectiveness of EAD and PEBD, we compare them with a nonduplication algorithm, a traditional duplication-based algorithm, and the dynamic voltage scaling (DVS) algorithm. Extensive experimental results using both synthetic benchmarks and real-world applications demonstrate that our algorithms can effectively save energy with marginal performance degradation.
A randomized study of a pregnancy and disease prevention intervention for Hispanic couples.

CONTEXT: Many Hispanic women are at elevated risk for HIV infection because of the sexual behavior of their male partner. Yet, couple-based risk-reduction interventions for this population have not been developed and scientifically evaluated. METHODS: A sample of 146 Hispanic couples who received either a risk reduction intervention or the community educational standard of care were followed up at three months (men and women) and six months (women only) to measure the consistency of both condom use and effective contraceptive use, and the frequency of unprotected vaginal sex. Analyses were conducted to identify differences between the two groups at baseline and follow-up interviews, and changes over time. RESULTS: At follow-up, the two groups did not differ on any risk-related outcomes; over time, both groups increased the reported consistency of condom use and of use of effective contraceptive methods, and reduced their frequency of unprotected sex. CONCLUSIONS: If further research confirms that simply bringing couples together for a single-session, culturally appropriate risk reduction intervention helps them adopt protective behaviors, more intensive (and costly) interventions may not be necessary.
A radiographic evaluation of elasticity ın idiopathic scoliotic curves: are lateral bending films reliable enough to estimate curve elasticity?

Results Measurements taken from lateral bending radiographs provided more reliable estimates of the postoperative correction compared to radiographs using manual wrist to ankle traction. Lateral bending was a more effective method to assess lumbar and thoracolumbar curves. The two tests were simiIar in ability to evaluate the elasticity of thoracic curves. A lack of patient cooperation in movement was attributed to inadequate assessment of curve elasticity seen in some of the lateral bending radiographs. Conclusion The lateral bending test usually is superior to manual traction method. Both methods for estimation of curve elasticity may be recommended because of the frequent, lack of patient cooperation in the lateral bending test. This compliance issue may result in an underestimation of the actual achieved correction.
Calibration of In-flight Maneuver Performance for the THEMIS and ARTEMIS Mission Spacecraft

We describe the development and details of in-flight calibration techniques used to obtain the required degree of accuracy for mission-required, small-scale trajectory adjustments. Using the dynamics data gathered from dozens of orbital-adjustment maneuvers previously conducted on the ARTEMIS and THEMIS spacecraft, the Space Sciences Laboratory (SSL) Flight Dynamics group has systematized a calibration process employing hill-climbing and grid searches for single segment and multi-segment maneuvers, respectively. This effort has resulted in the characterization of a nonlinear function of thruster performance scale factors and offsets to use in NASA Goddard’s GMAN software package for maneuver planning and reconstruction. To date, use of these factors has greatly reduced deviations between predicted and observed orbital state vector solutions and spinrate changes following a sequence of orbit-raising maneuvers intended to result in a lunar gravitational capture of the ARTEMIS probes in early 2010.
Survey of toxic algal (microcystin) distribution in Florida lakes

Abstract A survey of microcystin in 187 Florida lakes was completed from Jan to Dec 2006. Annual average microcystin concentrations of the 187 Florida lakes ranged from nondetectable (< 0.1 μ g/L) to 12 μ g/L, with concentrations in individual water samples (N = 862) ranging from nondetectable to 32 μ g/L. Only 7% of all the individual samples exceeded the World Health Organization (WHO) drinking guidance value of 1 μ g/L. Three individual water samples collected from two lakes (0.3%) exceeded the WHO recreational guidance value of 20 μ g/L. Using chlorophyll concentrations and Secchi depth measurements, tables were constructed to predict the probability that microcystin concentrations exceeded the WHO guidance values in Florida lakes. Additionally, six hypereutrophic lakes (Harris Chain of Lakes, Lake County, FL) were studied from Sep 2006 to Aug 2007 and 40% of the samples exceeded 1 μ g/L but none exceeded 20 μ g/L. This study also provides baseline information and relations between trophic status, sea...
The CSSP implementation plan for space plasma physics programs

The Committee on Solar and Space Physics (CSSP) has provided NASA with guidance in the areas of solar, heliospheric, magnetospheric, and upper atmospheric research. The budgetary sitation confronted by NASA has called for a prioritized plane for the implementation of solar and space plasma physics programs. CSSP has developed the following recommendations: (1) continue implementation of both the Upper Atmosphere Research Satellite and Solar Optical Telescope programs; (2) initiate the International Solar Terrestrial Physics program; (3) plan for later major free-flying missions and carry out the technology development they require; (4) launch an average of one solar and space physics Explorer per yr beginning in 1990; (5) enhance current Shuttle/Spacelab programs; (6) develop facility-class instrumentation; (7) augment the solar terrestrial theory program by FY 1990; (8) support a compute modeling program; (9) strengthen the research and analysis program; and (10) maintain a stable suborbital program for flexible science objectives in upper atmosphere and space plasma physics.
Evaluation and improvement of an autonomous access technique for a digital cordless telephone system

The author discusses the performance of an access technique in a digital cordless telephone system, often known as CT2 or telepoint. A telepoint system environment is simulated assuming typical fading statistics, and factors affecting access performance are examined. Due to contention among base stations, overall performance with spatially random access attempts is found to be very poor. Two modified access approaches, that can be used (while maintaining independence of ports' response) individually or in combination to significantly improve performance, are proposed. The first approach is to allow the ports to select random time windows (or preassign the ports in time windows); the second is to retry access in case of a failed attempt. Using the two in combination virtually assures capture in no more than two access attempts for any reasonable number of ports. Hence, the inclusion of time windows in the system design may be a necessary option. >
Traumatic Stress among Homeless Young Adults: Challenges and Treatment Issues

Traumatic Stress among Homeless Young Adults: Challenges and Treatment Issues Homeless emerging adults are one of this nation’s most underserved populations and are particularly vulnerable to the detrimental effects of trauma exposure, including developing PTSD. These young people typically reside in unstable and often abusive situations marked by violence and danger. They survive on the street through engaging in high risk behaviors, such as dumpsterdiving for food, panhandling/begging for money, and selling drugs or sex for money or shelter. These conditions result in a significant risk for serious health and mental health problems, including malnutrition, sexually transmitted diseases, depressive symptoms, posttraumatic stress, drug overdose and increased potential for selfharm and suicidal ideation.
Reconstruction of the flagellar apparatus in Ploeotia costata (Euglenozoa) and its relationship to other euglenoid flagellar apparatuses.

Abstract The flagellar apparatus of Ploeotia costata Farmer and Triemer was reconstructed using serial sectioning and TEM. The flagellar apparatus is similar to other euglenoids having two flagella arising from basal bodies connected by a striated fiber, and three asymmetrically arranged roots. The flagella emerge subapically from between the two ventral pellicle strips. The dorsal flagellum is 1/2 the body length and actively pulls the cell, while the ventral flagellum is twice the body length and drags along the substrate surface. The ventral and dorsal roots are on the opposite sides of their respective basal bodies, while the intermediate root is associated with the ventral flagellum on the side closest to the dorsal basal body. The dorsal root lines the dorsal side of the reservoir and after giving rise to the dorsal band lines the right side of the reservoir/canal. The ventral and intermediate roots join at the reservoir forming the intermediate-ventral root, which lines the left and ventral sides o...
The acetyl-CoA pathway of autotrophic growth

The most direct conceivable route for synthesis of multicarbon compounds from CO2 is to join two molecules of CO2 together to make a 2-carbon compound and then polymerize the 2-carbon compound or add CO2 successively to the 2-carbon compound to make multicarbon compounds. Recently, it has been demonstrated that the bacterium, Clostridium thermoaceticum, grows autotrophically by such a process. The mechanism involves the reduction of one molecule of CO2 to a methyl group and then its combination with a second molecule of CO2 and CoA to form acetyl-CoA. We have designated this autotrophic pathway the acetyl-CoA pathway [1]. Evidence is accumulating that this pathway is utilized by other bacteria that grow with CO2 and H2 as the source of carbon and energy. This group includes bacteria which, like C. thermoaceticum, produce acetate as a major end product and are called acetogens or acetogenic bacteria. It also includes the methane-producing bacteria and sulfate-reducing bacteria. The purpose of this review is to examine critically the evidence that the acetyl-CoA pathway occurs in other bacteria by a mechanism that is the same or similar to that found in C. thermoaceticum. For this purpose, the mechanism of the acetyl-CoA pathway, as found in C. thermoaceticum, is described and hypothetical mechanisms for other organisms are presented based on the acetyl-CoA pathway of C. thermoaceticum. The available data have been reviewed to determine if the hypothetical schemes are in accord with presently known facts. We conclude that the formation of acetyl-CoA by other acetogens, the methanogens and sulphate-reducing bacteria occurs by a mechanism very similar to that of C. thermoaceticum.
Approximate analysis and design of rectangular-lattice photonic crystals

We present a theoretical analysis of wave propagation in rectangular- and square-lattice photonic crystals by approximating the arbitrary refractive-index function with a staircase profile. This profile has a number of tunable parameters that allow one to fit the band structures of the staircase and the desired structure over a large frequency range. The staircase profile is such that its corresponding two-dimensional wave equation decomposes into two one-dimensional equations by means of a constant decoupling parameter. We show that basic features of the band structure and Bloch waves in photonic crystals can be analyzed theoretically through this simple approximation.
A sparse grid representation for dynamic three-dimensional worlds

Grid representations offer many advantages for path planning. Lookups in grids are fast, due to the uniform memory layout, and it is easy to modify grids. But, grids often have significant memory requirements, they cannot directly represent more complex surfaces, and path planning is slower due to their high granularity representation of the world. The speed of path planning on grids has been addressed using abstract representations, such as has been documented in work on Dragon Age: Origins. The abstract representation used in this game was compact, preventing permanent changes to the grid. In this paper we introduce a sparse grid representation, where grid cells are only stored where necessary. From this sparse representation we incrementally build an abstract graph which represents possible movement in the world at a high-level of granularity. This sparse representation also allows the representation of three-dimensional worlds. This representation allows the world to be incrementally changed in under a millisecond, reducing the maximum memory required to store a map and abstraction from Dragon Age: Origins by nearly one megabyte. Fundamentally, the representation allows previously allocated but unused memory to be used in ways that result in higher-quality planning and more intelligent agents.
Sexual Harassment of Females by Males in the Workplace: Small Business Contrasted with Large Businesses

Sexual harassment continues to be an important topic, receiving the attention of small and large businesses. Formal claims regarding unlawful, social-sexual behavior in the workplace doubled during the J 990's. Some small business owners believe that sexual harassment is not a crucial concern, compared with their counterparts in large businesses. Some small business owners possess the misconception that sexual harassment, regarding federal and state law, apply primarily to large businesses. Sexualization in the workplace occurs when sexual jokes, comments, innuendos, and sexual or seductive dress are tolerated, or encouraged, as well as the more blatant offense of improperly touching another employee. The membership of the Society for Human Resource Management was the database for this study. A random sample from small businesses of fewer than 500 employees and large businesses with more than 500 employees was selected Important findings indicate that sexual harassment was more of a problem for large firms as there is more male-female interaction and social pressure. This is true even though more training takes place in larger, rather than smaller, businesses. The findings may also indicate more of a reluctance by females in smaller firms to report such incidences. Respondents believe more formal training, education and behavior modeling, especially in small businesses, are needed to maximize the effectiveness of written policies.
More questions than answers.

To the Editor: I just completed reviewing the October issue of Physical Therapy and find myself both excited and frustrated. How exciting that the Philadelphia Panel has released these important data on the evidence of the efficacy of our most common treatments for very common musculoskeletal problems. How frustrating to learn that so few of the modalities that we have come to believe in actually show evidence of efficacy in controlled trials. I am left with more questions than answers, and I expect I am not alone. In our attempt to show evidence of efficacy, could we be too narrow in defining what constitutes evidence? Are we too narrow in measuring our outcomes? How much of what we observe as evidence when our patients improve might be due to a placebo effect? And how detrimental is the randomized controlled trial in identifying a placebo effect? Dr Anne Harrington of the Department of the History of Science at Harvard University suggested that only when our research began to measure very real physical effects of placebo did placebo come to be seen as a confounding variable in research.1 I contend that some cultures (eg, certain Asian cultures) tend to view nonspecific benefits as being part of the individuality of the healing process. I also would argue that some cultures do not even try to control for variables or to separate the physical from the metaphysical. Perhaps they are not driven by showing cause and effect in health care. The National Institutes of Health is currently funding studies that are looking at the placebo effect.2 According to the Web site for the National Center for Complementary and Alternative Medicine of the National Institutes of Health (http://nccam.nih.gov/fi/concepts/rfa) there are 2 program announcements inviting applications addressing different aspects of placebo. Data have shown …
Coupling spatial segregation with synthetic circuits to control bacterial survival

Engineered bacteria have great potential for medical and environmental applications. Fulfilling this potential requires controllability over engineered behaviors and scalability of the engineered systems. Here, we present a platform technology, microbial swarmbot, which employs spatial arrangement to control the growth dynamics of engineered bacteria. As a proof of principle, we demonstrated a safeguard strategy to prevent unintended bacterial proliferation. In particular, we adopted several synthetic gene circuits to program collective survival in Escherichia coli: the engineered bacteria could only survive when present at sufficiently high population densities. When encapsulated by permeable membranes, these bacteria can sense the local environment and respond accordingly. The cells inside the microbial swarmbot capsules will survive due to their high densities. Those escaping from a capsule, however, will be killed due to a decrease in their densities. We demonstrate that this design concept is modular and readily generalizable. Our work lays the foundation for engineering integrated and programmable control of hybrid biological-material systems for diverse applications.
Precision Atom Interferometry

While the current generation of atom interferometric force sensors perform at levels which compete favorably with the existing state-of-the-art, the full potential of these sensors has yet to be realized. Advances in the quality of the atom optics used to manipulate atomic de Broglie waves, the brightness of the atomic sources, and attaining full control over the quantum many-body wavefunction of the ensemble of interfering particles all promise to bring the performance levels of these sensors to levels of precision which may have dramatic future scientific and technological impact.
Organizational Effectiveness: An Alternative Perspective

A paradigm is proposed that views effectiveness as the ability of an organization to account successfully for its outputs and operations lo its various infernal and external constituencies. This framework can he used to assess effectiveness by examining organizational outputs and processes in a critical and holistic way. A review of (he existing literatures on organizational effectiveness and a case example are used to develop the proposed framework.
Energy barriers, entropy barriers, and non-Arrhenius behavior in a minimal glassy model

We study glassy dynamics using a simulation of three soft Brownian particles confined to a two-dimensional circular region. If the circular region is large, the disks freely rearrange, but rearrangements are rarer for smaller system sizes. We directly measure a one-dimensional free-energy landscape characterizing the dynamics. This landscape has two local minima corresponding to the two distinct disk configurations, separated by a free-energy barrier that governs the rearrangement rate. We study several different interaction potentials and demonstrate that the free-energy barrier is composed of a potential-energy barrier and an entropic barrier. The heights of both of these barriers depend on temperature and system size, demonstrating how non-Arrhenius behavior can arise close to the glass transition.
Discussion on Directly Measuring Method of Acoustic Properties for Sea Bottom Sediments in Laboratory

Besides measuring the acoustic properties of seafloor sediments in situ,it is also a method to measure the acoustic properties of seafloor sediments in laboratory.As a basic research,it's important to establish the geo-acoustics model by the application of sound wave parameters instrument which can be used to determine the sound velocity and attenuation of seafloor sediments.In this article,some questions are discussed in the process of measurement,which are meaningful in practice to acquire the accurate properties of seafloor sediments in laboratory.