cssi/SciSciGPT-SciSciNet huggingface dataset:
Alkaline Earth Organometallics

Abstract For over 100 years, the well-known and synthetically important Grignard reagents (RMgX) have dominated research in organoalkaline earth chemistry. Nevertheless, both the smallest (Be) and largest (Ca–Ba) members of the Group 2 metals have distinctive organometallic compounds with structures and reactivity that have no counterparts in the organomagnesium halides. The Group 2 metals are divalent, and their isolated compounds almost always display the + 2 oxidation state. They also feature strongly polar bonding in their compounds. The change in size from Be2 + to Ba2 + is nearly sixfold, however, and a correspondingly large range of coordination numbers (from 2 to 9) and structural types (from monomers to coordination polymers) are found in organoalkaline earth complexes. In recent years, sterically bulky ligands have been used increasingly to form complexes that have lower coordination numbers, greater solubility, and altered reactivity compared with compounds containing less bulky ligands. Computational investigations have also played a progressively more important role in describing the metal–ligand interactions in organoalkaline earth chemistry, and have been used to elucidate bonding arrangements (including fluxional processes) and mechanisms of catalysis. Although a large part of non-magnesium Group 2 chemistry has focused on cyclopentadienyl derivatives, non-cyclopentadienyl species (e.g., alkyls, acetylides, allyls, dienes, and other π-bound species) are now well represented with the heavier alkaline earth elements. Organoalkaline earth complexes have expanded from their traditional role in organic synthesis (the Grignard reagents and dialkylmagnesiums) to include applications in materials science such as the chemical vapor deposition of metals and metal oxides and the polymerization of polar monomers.
Thinking Critically about Critical Thinking: Assessing Critical Thinking of Business Students Using Multiple Measures.

Critical thinking is a skill that potential employers expect all graduates to possess. Hence, most business management programs consider critical thinking as an important student learning goal. Unf...
Evidence-Based Reasoning and Applications

This special CiSE issue features recent work on the theory and applications of evidence-based reasoning. Different approaches to this type of reasoning, including interactive and automatic ones, are discussed and illustrated in intelligence analysis, medicine, and cybersecurity.
Potential efficiency gains in payment programs from resolving spatial and temporal heterogeneity in the cost of supplying forest carbon

Abstract The environmental benefits and costs of conservation policies often vary over space and through time. Accounting for this spatial and temporal heterogeneity has important implications for the potential cost effectiveness of different payment program designs. In this study, we examine the cost efficiency gain from spatial and temporal targeting in payment designs for forest carbon storage in the Central and Southern Appalachian Mountains in the Eastern United States. We run a forest land change model and a carbon simulation model utilizing a panel data on forest land and its competing uses, economic returns, and spatial characteristics for each 1 km2 grid cells in 1992, 2001, 2006 and 2011. A time- and space-specific carbon cost for each individual 1 km2 grid cell is calculated that captures the spatial and temporal heterogeneity in carbon cost efficiency. From there, we compare carbon cost efficiency levels of various payment designs that allow for different degrees of spatial and temporal flexibility. We find that 1) spatial targeting improves carbon cost efficiency, and this efficiency gain is larger as payments become more narrowly targeted, 2) this carbon efficiency gain is present in all market conditions, but is largest in a moderately growing market and smallest in a downturn market, 3) accounting for temporal heterogeneity results in even larger carbon efficiency gains, almost double those from spatial targeting. Just as policies that enable spatial targeting (e.g., auctions) increase cost efficiency savings, so too will policy mechanisms that emphasize budget flexibility through time. These could include utilizing loans or flexible conservation financing, or allowing movement across budgeting categories within a given time period.
Using High Performance Computing for Parameter Sweep of S3D Applications

Electric ship design and simulation software can be used to identify design defects early in the design and significantly reduce the cost compared to later discovery. Depending on the complexity of the design and desired details, the simulation may take minutes to hours to run. Running many variations of a simulation for tradespace exploration or set-based design can take hours to days. This paper describes efforts to bring high performance computing (HPC) capabilities to one early stage ship design tool, S3D, as part of the Electric Ship Research and Development Consortium (ESRDC). Past and present HPC examples are presented.
Students connected to foster care: An overview of high school experiences

Abstract Youth in foster care aspire to attend college but enrollment and graduation rates remain low. High school experiences such as academic difficulties, low participation in college readiness courses, and residential or academic instability may impact youth’s postsecondary enrollment and success. This study examines the path from high school to college among a sample of 500 youth in care enrolled at a large, urban Northeastern public university system, focusing on residential and academic stability and academic outcomes. Univariable analyses were conducted to describe student data on number of Zip Code changes, high school transfers, SAT scores, AP exams, dual enrollment program participation, and on-time high school graduation. A one-sample Wilcoxon Signed-Ranks Test was used to determine if students in this sample spent significantly more time in high school than the anticipated four-year high school tenure. State and city averages were used as descriptive comparisons where applicable. Youth in the sample were slightly less mobile than they were in previous studies, with at least one ZIP Code change and one high school change. Compared to the city average, youth in the sample faced academic challenges in important college admissions predictors such as SAT scores, AP course and exam participation and performance, and four-year graduation rates credentials/diploma types. These findings reflect the instability experienced by youth in foster care as well as their subsequent under-preparedness for college-level work, and highlight the need for measures to understand the relationship between psychosocial factors, such as motivation, self-efficacy, supportive relationships, and postsecondary access and success.
CT-based pancreatic multi-organ segmentation by a 3D deep attention U-net network

Pancreatic cancer continues showing poor prognosis with a 5-year overall survival (OS) of 9% [1]. Stereotactic body radiotherapy (SBRT) has been increasingly adopted as the treatment option for locally advanced pancreatic cancer (LAPC). Accurate and robust segmentation of the abdominal organs on CT is essential to minimize excessive doses to organs-at-risk (OARs) such as stomach and duodenum. However, this task is tedious and time-consuming. In this work, we aimed to develop a 3D deep attention U-Net based network to automatically segment the pancreatic SBRT OARs that can significantly expedite the treatment planning process, while maintain high segmentation accuracy comparable to the ones manually contoured by the experienced physicians. 30 patients previously treated with pancreatic SBRT were included. Their CT and OAR contours including small bowel, large bowel, liver, stomach, spinal cord, left kidney, right kidney and duodenum were used as the training dataset. Attention gates (AGs) were incorporated in the U-net based network to effectively differentiate the organ boundaries. The mean Dice similarity coefficient (DSC) for large bowel, small bowel, duodenum, left kidney, right kidney, liver, spinal cord, and stomach were 0.89±0.05, 0.86±0.04, 0.79±0.04,0.86±0.04, 0.87±0.06, 0.86±0.02, 0.75±0.04 and 0.88±0.06, respectively.
Solar/Photovoltaic DC Systems: Basics and Safety

Solar photovoltaic (PV) systems are common and growing, with 42.4 GW of installed capacity currently in the United States and nearly 15 GW added in 2016. This paper will help electrical workers and firefighters understand some basic operating principles and hazards of PV DC arrays. We briefly discuss the effects of solar radiation and temperature on power output; PV module testing standards; methods for calculating the number of modules in a PV string; some National Electrical Code guidelines that are aimed toward improving array safety; DC array commissioning, periodic maintenance, and testing; arc flash hazard potential; ways firefighters can and do work safely around PV arrays; potential risk posed by moonlight and other light sources; and some unique DC-system hazards. We also present some statistics on PV DC array electrical incidents and injuries.
Joint Spatio-temporal Neural Source Reconstruction Using Electroencephalography and Near-infrared Spectroscopy

Electroencephalography (EEG) and near-infrared spectroscopy (NIRS) are commonly used for neural source reconstruction, but have limited spatial or temporal resolution. Using NIRS reconstruction as a spatial prior for EEG reconstruction, neural sources are spatio-temporally reconstructed.
Household Spending Patterns: A Comparison of Four Census Regions

This paper reviews the expenditures made by households in selected areas of the United States as defined by the Consumer Price Index (CPI) and classified into four regional areas. Following a model previously devised and published in the Monthly Labor Review, it then attempts to break down these aggregate expenditures into five categories of change which can impact total expenditures. These categories, or components of change in total expenditures, are population growth within a geographic region, the effects of changes in population concentrations between local areas within a geographic region, allowances for any changes in the definitions of goods and services as collected and priced by the CPI, price changes, and quantity changes. Some of the largest impacts in each region for each component are discussed. Comparisons of results are made between regions for selected goods and services in each of the eight major groups of commodities and services used by the CPI.
IN SEARCH OF PERMANENCY

President Clinton signed the Adoption and Safe Families Act (ASFA) into law on November 19, 1997. ASFA is designed to prevent children in foster care from being returned to unsafe homes and to find safe homes for children who are not able to return to their families. Some critics say that ASFA is too extensive and intrusive; others feel it does not go far enough. The author focuses on the practical issues of what ASFA has done so far and how various communities can still use it to ameliorate some of their child welfare problems. She begins with the history of child welfare in the United States, followed by an extensive discussion of ASFA's provisions. The author then addresses criticisms of some of ASFA's key components. A discussion of the ways the states have implemented ASFA follows. The author concludes that ASFA could be a powerful and important tool in aiding the child welfare system.
Data-Oriented distributed computing for science: reality and possibilities

As is becoming commonly known, there is an explosion happening in the amount of scientific data that is publicly available One challenge is how to make productive use of this data This talk will discuss some parallel and distributed computing projects, centered around virtual astronomy, but also including other scientific data-oriented realms It will look at some specific projects from the past, including Montage, Grist, OurOcean, and SCOOP, and will discuss the distributed computing, Grid, and Web-service technologies that have successfully been used in these projects.
Complexity upper bounds for classical locally random reductions using a quantum computational argument

We use a quantum computational argument to prove, for any integer k ≥ 2, a complexity upper bound for nonadaptive k-query classical locally random reductions (LRRs) that allow bounded-errors. Extending and improving a recent result of Pavan and Vinodchandran [PV], we prove that if a set L has a nonadaptive 2-query classical LRR to functions g and h, where both g and h can output O(log n) bits, such that the reduction succeeds with probability at least 1/2 + 1/poly(n), then L ∈ PPNP/poly. Previous complexity upper bound for nonadaptive 2-query classical LRRs was known only for much restricted LRRs: LRRs in which the target functions can only take values in {0, 1, 2} and the error probability is zero [PV]. For k > 2, we prove that if a set L has a nonadaptive k-query classical LRR to boolean functions g1, g2, ..., gk such that the reduction succeeds with probability at least 2/3 and the distribution on (k/2+ √k)-element subsets of queries depends only on the input length, then L ∈ PPNP/poly. Previously, for no constant k > 2, a complexity upper bound for nonadaptive k-query classical LRRs was known even for LRRs that do not make errors. Our proofs follow a two stage argument: (1) simulate a nonadaptive k-query classical LRR by a 1-query quantum weak LRR, and (2) upper bound the complexity of this quantum weak LRR. To carry out the two stages, we formally define nonadaptive quantum weak LRRs, and prove that if a set L has a 1-query quantum weak LRR to a function g, where g can output polynomial number of bits, such that the reduction succeeds with probability at least 1/2 + 1/poly(n), then L ∈ PPNP/poly.
MVPE: visual design of parallel simulation models

Simulation is an increasingly important aspect of network development, and parallelization of these simulations can result in tremendous time/performance improvements. However, tools for developing and parallelizing simulations are sadly lacking. The paper describes MVPE*, a visual programming environment for parallel simulation design.
A supramolecular triarm star polymer from a homotritopic tris(crown ether) host and a complementary monotopic paraquat-terminated polystyrene guest by a supramolecular coupling method.

The first supramolecular star polymer based on pseudorotaxane host−guest complexation was prepared from statistical complexation of a homotritopic tris(crown ether) host and monotopic paraquat-terminated polystyrene guest in solution. The formation of this supramolecular star polymer was confirmed by proton NMR characterization and viscosity studies.
Waterfowl toxicology: a review

Waterfowl populations may serve as sentinel species for natural and anthropogenic toxicologic problems in the environment. Unfortunately, many toxins cause nonspecific clinical signs, acute mortality, and subtle or no pathologic changes, making toxicologic investigations extremely difficult. The purpose of this article is to review important waterfowl toxins, including heavy metals, pesticides, botulism, mycotoxins, algal toxins, and petroleum oil. When applicable, clinical signs, diagnosis, pathologic findings, and treatment are discussed. Although most of the information in the literature is based on wild waterfowl populations or experimental toxicologic investigations, the information is also applicable to captive waterfowl populations.
Age of onset of social anxiety disorder in depressed outpatients

Onset of social anxiety disorder (SAD) often precedes that of major depressive disorder (MDD) in patients with this comorbidity pattern. The current study examined the association between three SAD onset groups (childhood, adolescent, adulthood) and clinical characteristics of 412 psychiatric outpatients diagnosed with MDD and SAD based on a semi-structured diagnostic interview. Childhood and adolescent SAD onset groups were more likely to report an onset of MDD prior to age 18 and have made at least one prior suicide attempt compared to the adulthood onset group. The childhood SAD onset group also was more likely to have chronic MDD, poorer past social functioning, and an increased hazard of MDD onset compared to the adulthood onset group. Findings suggest that patients with an onset of SAD in childhood or adolescence may be particularly at risk for a more severe and chronic course of depressive illness.
Matrix Isolation Infrared and ab Initio Study of the 1:1 Complexes of Bromocyclopropane with NH3 and (CH3)3N: Evidence for a Novel C−H···N Hydrogen Bond

Hydrogen-bonded complexes of bromocyclopropane with the strong bases ammonia and trimethylamine have been isolated and characterized for the first time in argon matrices at 16 K. Coordination of the proton adjacent to the Br substituent on the cyclopropane ring to the nitrogen of the base was evidenced by distinct blue shifts of the C−H(Br) bending modes in the infrared spectrum. These shifts (∼12 cm-1 for the in-plane bend and ∼6 cm-1 for the out-of-plane bend) are much smaller than those observed for alkenes and alkynes, suggesting a distinct but extremely weak interaction. Ab initio calculations yield an essentially linear BrC−H···NH3 hydrogen bond with a C−H···N distance of 2.301 A and a hydrogen bond energy of 2.35 kcal/mol, thus supporting that this hydrogen bond is one of the weakest observed thus far in a matrix. This study represents the first example of a (substituted) cyclopropane acting as a proton donor and only the second example of an alkane taking part in a C−H···N hydrogen bond.
Two Rating Indicators of Excellence in Teaching in Lecture-Format Courses:

Stepwise multiple regression analysis was used to predict two criterion measures of teaching excellence. Findings partially support Lowman's two-dimensional model of “masterful teaching.”
Optically Stimulated Luminescent Dosimetry for High Dose Rate Brachytherapy

Purpose: The objective was to determine whether optically stimulated luminescent dosimeters (OSLDs) were appropriate for in vivo measurements in high dose rate brachytherapy. In order to make this distinction, three dosimetric characteristics were tested: dose linearity, dose rate dependence, and angular dependence. The Landauer nanoDotTM OSLDs were chosen due to their popularity and their availability commercially. Methods: To test the dose linearity, each OSLD was placed at a constant location and the dwell time was varied. Next, in order to test the dose rate dependence, each OSLD was placed at different OLSD-to-source distances and the dwell time was held constant. A curved geometry was created using a circular Accuboost® applicator in order to test angular dependence. Results: The OSLD response remained linear for high doses and was independent of dose rate. For doses up to 600 cGy, the linear coefficient of determination was 0.9988 with a response of 725 counts per cGy. The angular dependence was significant only in “edge-on” scenarios. Conclusions: OSLDs are conveniently read out using commercially available readers. OSLDs can be re-read and serve as a permanent record for clinical records or be annealed using conventional fluorescent light. Lastly, OSLDs are produced commercially for $5 each. Due to these convenient features, in conjunction with the dosimetric performance, OSLDs should be considered a clinically feasible and attractive tool for in vivo HDR brachytherapy measurements.
Transport pathways for arsenic and selenium: A minireview

Arsenic and selenium are metalloids found in the environment. Arsenic is considered to pose the most significant potential threat to human health based on frequency of occurrence, toxicity and human exposure. Selenium, on the other hand, ranks only 147th in toxicity but, in contrast to arsenic, is a required micronutrient. Whether a toxin or micronutrient, their metabolism requires that cells to accumulate these metalloids. In this review we discuss the membrane proteins that transport arsenic and selenium into cells, from bacteria to humans, as well as some of the efflux proteins involved in detoxification.
Regulation of the Proinflammatory Effects of Fas Ligand (CD95L)

Fas ligand (CD95L) inhibits T cell function in immune-privileged organs such as the eye and testis, yet in most tissues CD95L expression induces potent inflammatory responses. With a stably transfected colon carcinoma cell line, CT26-CD95L, the molecular basis for these divergent responses was defined. When injected subcutaneously, rejection of CT26-CD95L was caused by neutrophils activated by CD95L. CT26-CD95L survived in the intraocular space because of the presence of transforming growth factor-beta (TGF-beta), which inhibited neutrophil activation. Providing TGF-beta to subcutaneous sites protected against tumor rejection. Thus, these cytokines together generate a microenvironment that promotes immunologic tolerance, which may aid in the amelioration of allograft rejection.
Bombardment of Metal Surfaces by Slow-Moving Electrons

Secondary Electrons Produced by Electronic Bombardment of Nickel.---The main features of the apparatus used are: an equi-potential nitrate-coated Pt cathode heated by radiation from a tungsten spiral filament; a series of insulated diaphragms to limit the beam of primary rays and for use in determining their velocity; and a long Faraday cylinder in front of which the nickel target could be alternately interposed and withdrawn. By baking out the tube and using liquid air traps an extremely low vacuum corresponding to less than ${10}^{\ensuremath{-}7}$ mm. was attained. The secondary current was determined from the difference between the current to the Faraday cylinder and that to the interposed target. (I) Ratio of the secondary (emergent) to the primary (incident) electron current was found to be independent of the roughness of the surface, but to vary with the treatment. After heating the target red-hot by high frequency induction for some minutes, a limiting curve was reached which probably represents the characteristics of nickel itself, free from surface contamination. In this case the secondary electrons begin when the primary velocity is as low as 0.2 volt; the ratio to primary current then increases rapidly with primary velocity to about 4 volts, remains constant to about 9 volts, then again increases reaching a value of unity for a primary velocity corresponding to about 260 volts. The effect of exposure to air or hydrogen is to increase very considerably the secondary current and to round out the flat part of the curve between 4 and 9 volts. (2) Velocity distribution curves of the secondary electrons indicate that for primary electrons of less than 9 volts velocity, most of the secondary electrons have velocities nearly equal to the primary velocity, while for primary velocities above 9 volts, the percentage of secondary electrons having small velocities increases with the primary velocity, although a small proportion have velocities nearly equal to the primary velocity up to at least 110 volts.Reflection and Emission of Electrons from a Nickel Surface Bombarded with Electrons of Velocity 0 to 260 Volts.---It is suggested by the above results, that reflection occurs for all the primary velocities investigated, and that emission or ionization begins at about 9 volts and increases with the primary velocity.Contact difference of potential between a gas-free nickel surface and an ordinary baked nickel surface was found to be 0.8 volt.Method of making a gas-tight glass joint for high vacuum work by soldering with Wood's metal, the platinized and copper-coated surfaces of a ground joint, is described.
Transmission and infectivity studies on Nosema kingi in Drosophila willistoni and other drosophilids

Diagnostic studies on the relationship between Drosophila willistoni and Nosema kingi revealed that adult D. willistoni can acquire the microsporidian via the oral route from fecal contamination and transovarially. At least 50% of the flies exposed to fecal material from infected flies contained the parasite when examined two or three weeks later. 50–81% of the offspring which emerged from eggs laid by parasitized females were infected with N. kingi 14–21 days later. Infectivity experiments using other drosophilids indicated N. kingi infections can be transmitted to D. sturtevanti Duda, D. melanogaster Meigen, D. persimilis Dobzhansky and Epling, D. pseudoobscura Frolowa, D. virilis Sturtevant, D. simulans Sturtevant, and D. ananassae Doleshall without morphological changes occurring in the stages of the parasite and without changes of behavioural patterns in these experimental hosts.
Transmission of a turbulent boundary layer wall pressure field through an elastomeric coating

Abstract The wall pressure fluctuations beneath a turbulent boundary layer introduce flow-induced noise and vibration which limits the performance of acoustic arrays. One method for mechanically filtering this energy is to separate the acoustic sensors from the fluid–solid interface with an elastomeric coating. Long wavelength acoustic energy is transmitted across the coating, and shorter wavelength energy from convected turbulence is attenuated. Experiments were conducted in an acoustically quiet water tunnel to measure the wall pressure fluctuations under 0.635 mm and 1.27 mm thick elastomeric coatings. Autospectra, magnitude and phase of the coherence, and convection velocities are presented for the range of Reynolds numbers 7540 θ Blake (1984) is shown to accurately predict the attenuations in the autospectra. The cross-spectral model given by Corcos (1963) is shown to be valid for measurements of the wall pressure coherence beneath the coatings.
Controlling the Interface Dynamics at Au Nanoparticle–Oxide Interfaces

With interface sizes rapidly reducing to the nanometer scale, it has become vital to understand how size and structure can affect transport behavior between materials in order to tune the energy barrier for various applications. In this study, the fabrication of Schottky barriers between 20 nm Au nanoparticles and Nb-doped SrTiO3 substrates is reported. The calculated barrier height and ideality factors are compared for dopant concentrations ranging over three orders of magnitude. The results show that the lowest doped substrates exhibit transport characteristics dominated by thermionic emission while the highest doped substrates are dominated by tunneling and the transition is best described by classical theory with the addition of edge effects to account for nonideal behavior.
Diagnostic Procedures for Detecting Nonlinear Relationships between Latent Variables.

Structural equation models are commonly used to estimate relationships between latent variables. Almost universally, the fitted models specify that these relationships are linear in form. This assumption is rarely checked empirically, largely for lack of appropriate diagnostic techniques. This article presents and evaluates two procedures that can be used to visualize and detect nonlinear relationships between latent variables. The first procedure involves fitting a linear structural equation model and then inspecting plots of factor score estimates for evidence of nonlinearity. The second procedure is to use a mixture of linear structural equation models to approximate the underlying, potentially nonlinear function. Targeted simulations indicate that the first procedure is more efficient, but that the second procedure is less biased. The mixture modeling approach is recommended, particularly with medium to large samples.
A methodology for the calculation of stress migration in die-level interconnects

Abstract An analytic methodology is presented for the examination of stress migration in the built up interconnect structures on integrated circuit die. The methodology uses finite element analysis combined with a presumed diffusion mechanism to define a vacancy accumulation site and to characterize the flux of vacancies. This physics-based approach accounts for the effects of time, temperature, material systems and interconnect geometry on stress migration. The method should be generally applicable to a wide range of interconnect structures and will find utility in the design of stress migration tolerant designs as well as in failure analysis. Through examples, stress migration within copper lines and vias with low- k and SiO 2 dielectrics is examined. The methodology predicts increased vacancy fluxes with increases in exposure time, line width and temperatures within the range studied. A fundamental mechanism suggesting heightened vacancy fluxes with a low- k dielectric over a SiO 2 dielectric is described. Finally, the methodology is exercised to demonstrate that the apparent activation energy obtained through stress migration testing of built up interconnect structures may not correspond with the governing diffusion mechanism.
An overview of NASA efforts on zero boiloff storage of cryogenic propellants

Future mission planning within NASA has increasingly motivated consideration of cryogenic propellant storage durations on the order of years as opposed to a few weeks or months. Furthermore, the advancement of cryocooler and passive insulation technologies in recent years has substantially improved the prospects for zero boiloff storage of cryogenics. Accordingly, a cooperative effort by NASA's Ames Research Center (ARC), Glenn Research Center (GRC), and Marshall Space Flight Center (MSFC) has been implemented to develop and demonstrate "zero boiloff" concepts for in-space storage of cryogenic propellants, particularly liquid hydrogen and oxygen. ARC is leading the development of flight-type cryocoolers, GRC the subsystem development and small scale testing, and MSFC the large scale and integrated system level testing. Thermal and fluid modeling involves a combined effort by the three Centers. Recent accomplishments include: 1) development of "zero boiloff" analytical modeling techniques for sizing the storage tankage, passive insulation, cryocooler, power source mass, and radiators; 2) an early subscale demonstration with liquid hydrogen 3) procurement of a flight-type 10 watt, 95 K pulse tube cryocooler for liquid oxygen storage and 4) assembly of a large-scale test article for an early demonstration of the integrated operation of passive insulation, destratification/pressure control, and cryocooler (commercial unit) subsystems to achieve zero boiloff storage of liquid hydrogen. Near term plans include the large-scale integrated system demonstration testing this summer, subsystem testing of the flight-type pulse-tube cryocooler with liquid nitrogen (oxygen simulant), and continued development of a flight-type liquid hydrogen pulse tube cryocooler.
Synthesis and characterization of acrylonitrile methyl acrylate statistical copolymers as melt processable carbon fiber precursors

Abstract Statistical (random) copolymers of acrylonitrile (AN) and methyl acrylate (MA) have been synthesized by free radical homogeneous (solution) and heterogeneous (suspension) methods. Selected compositions can be fabricated by environment friendly, solvent-free melt spinning and are of interest as precursors for carbon fibers. The dynamic and steady state melt viscosities of these copolymers were studied as a function of molecular weight and copolymer composition. Melt processability at 200–220 °C depends on the copolymer composition, and also on the molecular weight, which was controlled by chain transfer agent concentration and reaction temperature. Copolymers of controlled molecular weight containing 10 or more mol[percnt] of methyl acrylate show good melt processability, which can be further enhanced by stabilizers. This thermoplastic behavior is supported by a significant increase in temperature by the cyclization exotherm. Thermal analysis (differential scanning calorimetry, dynamic mechanical analysis) further illustrates that the comonomers retarded the cyclization, which permits thermoplastic processing.
Optical encryption and multiplexing of personal identification information using orthogonal code

A new technique is proposed for optical encryption and multiplexing of binary characters and images used for personal identification information. Different binary images can first be encrypted using orthogonal code and then multiplexed together in the spatial domain. The resulting encrypted single image provides security as well as makes efficient use of storage and/or transmission capacity. The image can finally be decrypted and the individual input images can be decoded employing the same orthogonal code set. Because of the orthogonal nature of the code used, the encryption and decryption processes do not deteriorate the quality of the images employed. Also, the proposed technique involves a very simple architecture, as it does not require any mathematical transformation.
Risk of Dysphagia and Speech and Language Delay in PHACE Syndrome

PHACE (posterior fossa, hemangioma, arterial lesions, cardiac, and eye) syndrome consists of infantile hemangiomas of the head and neck along with a spectrum of noncutaneous anomalies. Neurodevelopmental abnormalities have also been noted. Here we describe the association between PHACE syndrome and abnormalities in oropharyngeal development and coordination manifesting as dysphagia or speech and language delay. A retrospective chart review was conducted of 34 patients with PHACE syndrome. Data were collected from prior clinical notes and radiographic studies and the results of a comprehensive questionnaire that those who attended the July 2012 PHACE Syndrome Family Conference completed. Seventeen of 34 patients with PHACE syndrome and signs or symptoms of dysphagia or speech or language problems were included for analysis. Nine had dysphagia, seven had a history of cardiac surgery, four had a posterior fossa malformation, and seven had lip or oropharynx hemangiomas. Speech or language delay was noted in 16; posterior fossa abnormalities and lip or oropharynx hemangiomas were the most commonly seen associated finding in this group. There was considerable overlap between subset populations with dysphagia, speech delay, and language delay. A subset of individuals with PHACE syndrome experience dysphagia, speech delay, or language delay. This risk seems to be greater in certain subsets of patients, including those with posterior fossa malformations or lip or oropharynx hemangiomas and those with a history of cardiac surgery. Although this descriptive study was not comprehensive enough to examine prevalence, the high incidence of dysphagia and speech and language delay seen in our cohort warrants future prospective studies to further investigate the association.
The role of gastric mucosal blood flow and H+ back-diffusion in the pathogenesis of acute gastric erosions.

Abstract To evaluate the relationship between ischemia and disruption of the gastric permeability barrier in the pathogenesis of acute gastric erosions, we studied the effect of (1) hemorrhagic shock, (2) topical application of p -chloromercuribenzene sulfonate (PCMBS), and (3) shock plus PCMBS on total and mucosal blood flow, H + back-diffusion, and mucosal injury in 14 dogs. The fractional distribution of blood flow through the layers of gastric tissue remained unchanged during control, shock, and reinfusion periods. Exposure of the mucosa to PCMBS resulted in a significant increase in H + back-diffusion, which was accompanied by a rise in mucosal blood flow. Hemorrhagic shock alone caused a marked mucosal ischemia without disruption of the permeability barrier. The severest mucosal injury occurs only under experimental conditions where ischemia and increased H + back-diffusion are induced simultaneously. These results suggest that: (1) A cause-effect relationship does not exist between ischemia and barrier disruption in the pathogenesis of acute ulcerations. (2) Mucosal blood flow may play an important role in the disposal of H + permeating the mucosa. (3) The ratio of mucosal blood flow to back-diffusion of H + may determine the degree of mucosal injury.
Order types of free subsets

We give for ordinals α a lower bound for the least ordinal α(β) such that Frordℵξ(α(β),β) and show that given enough measurable cardinals there are forcing extensions where the given bounds are sharp.
Limitations in qualitative point of care hCG tests for detecting early pregnancy.

Abstract Background Detection of early pregnancy in the healthcare setting is important for proper patient management. Qualitative point-of-care (POC) human chorionic gonadotropin (hCG) testing is often used. There is a gap in the literature for evaluating patient samples with low ( Methods Specimens (urine, n = 289; serum, n = 269) with hCG concentrations between 2 and > 5000 IU/l were evaluated by hCG POC testing. Approximately half of these had an hCG concentration Results The OSOM and QuickVue + devices were able to detect hCG in 53% (OSOM) and 78% (QuickVue +) of urine samples with an hCG concentration range between 20 and 300 IU/l. Serum samples with an hCG concentration range between 10 and 300 IU/l gave positive results in 79 and 91% of samples tested using the OSOM and QuickVue +, respectively. False negative results could not be attributed to the high-dose hook effect, the hCG variant effect, or the interpreters' evaluation. The mean gestational age for specimens corresponding to the false negative results was 4 weeks. Conclusions The sensitivity of 2 commonly used hCG POC devices is insufficient for detecting very early pregnancy.
Building large scale mosiacs from Landsat data

This paper describes the process and tools used for creating a full resolution seamless Landsat mosaic of the continental U.S. at 30 meters per pixel. The 6-band, 150GB image was built from 428 individual Landsat scenes of the Multi-Resolution Land Characteristics (MRLC) dataset. Custom designed software based on SGI ImageVision framework was developed on JPL supercomputers to accomplish this task as a single step operation, with minimal operator input. Novel techniques were used to deal with data storage and access issues. Various color matching algorithms can be used to generate a parameter set, which in turn controls all the details of building the mosaic. Some of the tested algorithms and their results will also be discussed.
Combined heterozygosity of factor V leiden and the G20210A prothrombin gene mutation in a patient with cerebral cortical vein thrombosis.

Cerebral venous thrombosis (CVT) is a rare type of stroke with a variety of causes. Several reports have suggested that either factor V Leiden or G20210A prothrombin gene mutation is associated with an increased risk of CVT. The genetic thrombophilias are typically associated with other predisposing factors. We report a unique case of CVT in a patient with both the factor V Leiden and the G20210A prothrombin gene mutations without other identifiable precipitating factors in a 28-year-old white male in good health. MRI and cerebral arterial angiography showed cerebral cortical venous thrombosis. This case suggests that combined heterozygous individuals may be particularly prone to spontaneous thrombosis, like CVT.
A simple method of making an implant-level impression when presented with limited space, unfavorable implant positions, or problematic implant angulations

Making an implant-level impression for the purpose of abutment selection when implants are placed in limited space, unfavorable positions, or compromising angulations can be a time-consuming procedure. An impression procedure is presented that makes use of either prefabricated screw-retained titanium implant index copings or plastic snap-on implant index copings to help resolve problematic implant placement. Both the titanium and plastic implant index copings are easy to modify and therefore make impression procedures more predictable.
Mutagenesis at the ad-3A and ad-3B loci in haploid UV-sensitive strains of Neurospora crassa IV. Comparison of dose—response curves for MNNG, 4NQO and ICR-170 induced inactivation and the mutation-induction

Abstract The genetic effects of MNNG, 4NQO and ICR-170 have been compared on 5 different UV-sensitive strains and a standard wild-type strain of Neurospora crassa with regard to inactivation and the induction of forward-mutations at the ad-3A and ad-3B loci. Whereas all UV-sensitive strains ( upr -1, uvs -2, uvs -3, uvs -5 and uvs-6 ) are more sensitive to inactivation by MNNG and ICR-170 than wild-type, only uvs-5 shows survival comparable to wild-type after 4NQO treatment, all other strains are more sensitive to 4NQO. In contrast to the effects on inactivation, a wide variety of effects were found for the induction of ad-3A and ad-3B mutations: higher forward-mutation frequencies than were found in wild-type were obtained after treatment with MNNG or 4NQO for upr-1 and uvs-2 , no significant increase over the spontaneous mutation frequency was found with uvs-3 after MNNG, 4NQO or ICR-170 treatment; mutation frequencies comparable to the found in wild-type were obtained with uvs-6 after MNNG, 4NQO or ICR-170 treatment and with upr-1 after ICR-170 treatment. Lower forward-mutation frequencies than were found in wild-type were obtained with uvs-2 after ICR-170 treatment and with uvs-5 after MNNG, 4NQO or ICR-170 treatment. These data clearly show that the process of forward-mutation at the ad-3A and ad-3B loci is under genetic control by mutations at other loci (e.g. upr-1, uvs-2, uvs-3, uvs-5 and uvs-6 ) and that the effect is markedly mutagen-dependent.
Student designed laboratory experiments in biomedical instrumentation

The laboratory portion of a graduate course in biomedical instrumentation is described. The experiments were not developed by the teacher, but rather by the students. Each student selected a topic, did outside reading, developed the experiment, and wrote up the procedure. During the second half of the semester each student ran all experiments developed by the other students, thus ensuring a commonality of experience. The brief description of the experiments given here may suggest ideas for other teachers in this specialty. There are advantages to student designed experiments. The teacher's work load is reduced during both the development and the write-up of the experiment. The student's interest is heightened by the design aspects of this open-ended situation. His output is examined by his peers, as well as by his teacher; thus increasing motivation. The format of student designed laboratory experiments may be useful in other courses where we desire to change the student's experience from passive following directions to more active participation in design.
Dosimetric comparison of three different involved nodal irradiation techniques for stage II Hodgkin's lymphoma patients: conventional radiotherapy, intensity-modulated radiotherapy, and three-dimensional proton radiotherapy.

Purpose To compare the dose distribution to targeted and nontargeted tissues in Hodgkin's lymphoma patients using conventional radiotherapy (CRT), intensity-modulated RT (IMRT), and three-dimensional proton RT (3D-PRT). Methods and Materials CRT, IMRT, and 3D-PRT treatment plans delivering 30 cobalt Gray equivalent (CGE)/Gy to an involved nodal field were created for 9 Stage II Hodgkin's lymphoma patients ( n = 27 plans). The dosimetric endpoints were compared. Results The planning target volume was adequately treated using all three techniques. The IMRT plan produced the most conformal high-dose distribution; however, the 3D-PRT plan delivered the lowest mean dose to nontarget tissues, including the breast, lung, and total body. The relative reduction in the absolute lung volume receiving doses of 4–16 CGE/Gy for 3D-PRT compared with CRT ranged from 26% to 37% ( p p p p = .03). The mean dose to the breast was significantly less for 3D-PRT than for either IMRT or CRT ( p = .03) The mean dose and absolute volume receiving 4–30 CGE/Gy for the heart, thyroid, and salivary glands were similar for the three modalities. Conclusion In this favorable subset of Hodgkin's lymphoma patients without disease in or below the hila, 3D-PRT significantly reduced the dose to the breast, lung, and total body. These observed dosimetric advantages might improve the clinical outcomes of Hodgkin's lymphoma patients by reducing the risk of late radiation effects related to low-to-moderate doses in nontargeted tissues.
Minority perceptions of the police: a state-of-the-art review

Purpose – The purpose of this paper is to provide a comprehensive literature review of empirical studies that have examined perceptions and attitudes of the police across various racial and ethnic groups. The specific focus aimed to highlight if minorities perceive the police differently compared to their white counterparts. Design/methodology/approach – A systematic literature search of various academic databases (Criminal Justice Abstracts, EBSCO Host, Web of Science, etc.) was conducted. Searches on Google Scholar were also conducted to locate empirical articles that are presently forthcoming in academic journals. Findings – The meta-review identified 92 studies that matched the selection criteria. The majority of the studies focussed on black/white, non-white/white, and black/Hispanic/white comparisons. Overall, individuals who identified themselves as black, non-white, or minority were more likely to hold negative perceptions and attitudes toward the police compared to whites. This finding held regar...
Ethnic Residential Concentrations with Above-Average Incomes

Are residents of ethnic concentrations necessarily poor? We tested this notion with Census 2000 data for Asian and Latino households in the New York, Los Angeles, and San Francisco CMSAs. Ethnic concentrations included all census tracts in which the group comprised over 40% of the population. While many residential concentrations had low incomes, 11% of concentrated Latinos and 57% of concentrated Asians had incomes above their metropolitan medians for all households. Moreover, 18% of concentrated Asians lived in tracts with incomes at least 50% higher than the metropolitan medians. Higher-income residents within concentrations were more likely to be U.S.-born and proficient in English. Thus scholars need to revise the widespread view that people living in ethnic concentrations are poor. Many Asians and Latinos who can afford homes in mostly White neighborhoods prefer to live where both Whites and their group are well represented.
Do rat hepatic microsomes contain multiple NADPH-supported fatty acid chain elongation pathways or a single pathway?

Abstract [2- 14 C]- trans -2-hexadecenoyl CoA (16:1) and [2- 14 C]- trans -2-cis-8,11,14-eicosatetraenoyl CoA (20:4) were chemically synthesized and employed as competitive substrates for the liver microsomal trans -2-enoyl CoA reductase component of the fatty acid chain elongation system. Both 7.5 μM and 15 μM 20:4 competitively inhibited the reduction of 16:1 CoA to palmitoyl CoA. In addition, the reduction of both substrates was identically inhibited to the same extent by the acetylenic derivative, dec-2-ynoyl CoA. Furthermore, trypsin, chymotrypsin and subtilisin inhibited trans -2-enoyl CoA reductase activity when three different substrates were employed—16:1, 20:4 and trans -2-cis-11-octadecadienoyl CoA (18:2). These results are consistent with the hypothesis of multiple condensing enzymes connected to a single elongation pathway.
Volatility of ten priority pollutants from fortified avian toxicity test diets

With a few important exceptions, most pesticides have low volatility. However, a significant number of the industrial chemicals under the jurisdiction of TSCA have sufficient volatility to affect availability in fortified test diets and consequently the test results. Although extremely volatile chemicals might evaportate from test diets, there is insufficient data to indicate what levels of volatility are of concern. Volatility may be only one of a variety of factors influencing the fate of organic chemicals in test diets. Other mechanisms such as hydrolysis, adsorption, and photolysis should also be considered, but for many chemicals having significant vapor pressures, volatility is likely to be the major source of loss.