cssi/SciSciGPT-SciSciNet huggingface dataset:
Struggling for a Diverse but Fair Policy: Policy Challenges to Implementing English at the Primary School Level in Japan

After many false starts, the Japanese government has mandated the teaching of English as an academic subject at the 5th- and 6th-grade levels, beginning in 2020. This means that English is part of the accountability system from the 5th grade until college in Japan. Compared with neighboring Asian countries, the Japanese government has taken slow steps to implement English at the primary-school level, with the process reflecting complicated domestic issues as well as global forces underlying policy decision. This chapter situates primary-school English education policies in the larger societal context in Japan and discusses the challenges to their implementation. There exists a serious mismatch between the policy assumption that English proficiency is a global competency and the realities of day-to-day life in much of Japan. In the context of growing concerns about the nation’s decline in its economic and political presence in the world as well as increasing social-economic disparities within Japanese society, centralizing the diverse local practices in primary English education may promote unfairness as long as practical English skills are viewed as representative of global competence and are granted a significant role in the exam-based educational accountability system in Japan.
Machine Learning Analysis of 2×1 VCSEL Array Coherence and Imaginary Coupling Coefficient

Machine learning is used to estimate the coherent-coupling power enhancement from 2 × 1 VCSEL arrays and serves to identify coherent non-Hermitian operation.
Monoxygenases. VII. Camphor ketolactonase I and the role of three protein components.

The ketolactonase I system in Pseudomonas putida described by Conrad, Lieb, and Gunsalus (J. Biol. Chem., 240, 4029 (1965)), as a monoxygenase with the stoichiometry DPNH + O2 + ketone → DPN + H2O + lactone is separated into three types of protein components, and a specific function is assigned to each.
Ischemic cardiomyopathy: the myopathy of coronary artery disease. Natural history and results of medical versus surgical treatment.

Abstract Clinical, hemodynamic and angiographic data were analyzed in 66 patients with coronary artery disease and severe generalized left ventricular dysfunction (ischemic cardiomyopathy) in order to determine their prognosis and examine the results of medical and surgical management. Seventy-six percent of patients had angina, 85 percent a history of one or more myocardial infarctions, 73 percent cardiomegaly, 38 percent mitral regurgitation, 98 percent severe stenosis of two or three major coronary arteries, and 100 percent a left ventricular ejection fraction of 25 percent or less. Forty-two patients were managed medically, and 24 surgically with aortocoronary bypass grafts or ventricular plication, or both. The clinical and hemodynamic findings in both groups were nearly identical. In a follow-up period of 12 months, the mortality rate was 31 percent in the medical group and 50 percent in the surgical group, with 83 percent of the surgical deaths occurring within 1 month of operation. There was no significant difference in the functional status of medical and surgical survivors. Regardless of therapy, patients with mitral regurgitation or a left ventricular end-diastolic pressure of 24 mm Hg or greater had a significantly higher mortality rate than patients without these findings. This study indicates that patients with ischemic cardiomyopathy have a poor prognosis, and surgical intervention with current available techniques has a high operative mortality rate without significantly altering the symptoms in the survivors.
Successful Replacement of Artemia salina nauplii with Marine Rotifers (Brachionus plicatilis) in the Diet of Preadult Zebrafish (Danio rerio).

Abstract Previously established rearing protocols for zebrafish begin feeding with marine rotifers (Brachionus plicatilis), followed by Artemia nauplii until the fish reach subadult stage, the developmental time point at which they can be most easily transitioned onto a processed diet. However, the inclusion of Artemia is less than ideal, given its fluctuating availability and high costs. We tested whether or not we could replace Artemia with rotifers during our normal rearing sequence and still meet published performance standards for (i) weaning fish onto a processed diet by 25 days postfertilization (dpf) and (ii) successful breeding by 60 dpf. Here, we present the results of trials where wild-type and casper zebrafish were fed exclusively with rotifers (R) or rotifers followed by Artemia (RA) for the first 25 dpf after which point all fish were transitioned to a processed diet (Gemma Micro 300). We measured growth and survival at days 25 and 60, and tested for reproductive capability at 60 dpf. While ...
Accelerating machine-learning kernels in hadoop using FPGAs

Big data applications share inherent characteristics that are fundamentally different from traditional desktop CPU, parallel and web service applications. They rely on deep machine learning and data mining applications. A recent trend for big data analytics is to provide heterogeneous architectures to allow support for hardware specialization to construct the right processing engine for analytics applications. However, these specialized heterogeneous architectures require extensive exploration of design aspects to find the optimal architecture in terms of performance and cost. % Considering the time dedicated to create such specialized architectures, a model that estimates the potential speedup achievable through offloading various parts of the algorithm to specialized hardware would be necessary. This paper analyzes how offloading computational intensive kernels of machine learning algorithms to a heterogeneous CPU+FPGA platform enhances the performance. We use the latest Xilinx Signboards for implementation and result analysis. Furthermore, we perform a comprehensive analysis of communication and computation overheads such as data I/O movements, and calling several standard libraries that can not be offloaded to the accelerator to understand how the speedup of each application will contribute to its overall execution in an end-to-end Hadoop MapReduce environment.
MOAR: a multi-channel opportunistic auto-rate media access protocol for ad hoc networks

The IEEE 802.11 wireless media standard supports multiple frequency channels as well as multiple data rates at the physical (PHY) layer. In this paper, we introduce the multi-channel opportunistic auto rate (MOAR), an enhanced MAC protocol for multi-channel and multi-rate IEEE 802.11 enabled wireless ad hoc networks to opportunistically exploit the presence of frequency diversity (in the form of multiple frequency channels). The key mechanism of MOAR is that if the signal to noise ratio on the current channel is not favorable, mobile nodes can opportunistically skip to better quality frequency channels enabling data transmission at a higher rate. As channel separation for IEEE 802.11 is greater than the coherence bandwidth, different channels experience independent fading and hence there is a high probability that the skipping nodes will find better channel conditions on one of the other frequency channels. Each skip comes at the cost of resources spent in channel measurement since channel quality of different channels is not known a priori. Consequently, we devise an optimal skipping rule for MOAR which maps the channel conditions at the PHY layer to a MAC rule which allows each node to determine its optimum number of skips based on average channel conditions. Finally, we perform an extensive set of ns-2 simulations to evaluate the performance of MOAR and the impact of such factors as location distribution, channel conditions and error in channel measurements on the throughput gains offered by MOAR.
The Use of Tributylphosphine and 4-(Aminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole in the Study of Protein Sulfhydryls and Disulfides

Abstract The use of the reagent tributyl phosphine (Bu 3 P) to reduce disulfides (Ruegg, U. T., and Rudinger, J., Methods Enzymol. 47, 111-116, 1977) and of 4-(aminosulfonyl)-7-fluoro-2, 1 ,3-benzoxadiazole (ABD-F) to block free sulhydryl groups (Toyo′oka, T., and Imai, K. Anal. Chem. 56, 2461-2464, 1984) is well established in the literature. Since the two reagents apparently do not react with each other, their combination offers a convenient and quite general method for the complete characterization of free Cys (SH) and crosslinked Cys (S-S) in proteins (Kirley, T. L., J. Biol. Chem. 264, 7185-7192, 1989). We review some of the characteristics of the reaction of these reagents with Cys in peptides and proteins and some of the properties of the ABD-Cys derivatives. The review includes reactions with model compounds (e.g., Cys and glutathione), proteins such as enolase from yeast and rabbit muscle, containing only free Cys, a protein, fetuin, containing only crosslinked Cys, and a protein, superoxide dismutase, containing both free and crosslinked Cys. In all cases the direct comparison of the tryptic or chymotryptic peptides derived from the products of parallel reactions of the protein with ABD-F alone and with ADB-F together with Bu 3 P permitted the determination of both free and total Cys in the protein. Sequencing the fluorescent ABD-peptides established the position of the Cys residues in the primary sequence. To determine the pairing of Cys residues in disulfide bonds, the individual peptides from a nonreduced protein sample, separated and collected by IIPLC, were treated simultaneously with ADB-F and Bu 3 P, and the resulting single or paired fluorescent peptides, separated and collected after rechromatography, were identified by sequencing. The ability to reduce disulfides and block the resulting thiols simultaneously in a single reaction, the stability of ABD-Cys to acid hydrolysis, and the recovery, albeit in low yield, of PTH-(ABD-)Cys on sequencing, along with the characteristic fluorescence of ABD-thiol derivatives, are all very favorable features of this methodology. The apparently strong effect of environmental factors on the relative fluorescence intensity of ABD-Cys peptides represents a minor disadvantage; Cys-containing peptides with very low fluorescence may be encountered and must be anticipated in the analysis of unknown proteins.
A study of antibiosis between wind-borne molds and insect larvae from wind-borne eggs

Abstract 1.1. D. melanogaster eggs are wind borne, and they develop larvae that will prevent, destroy, or retard the growth of certain species of molds on a culture medium. 2.2. The larvae prevent mold growth on a culture medium if they are present on the medium at the time of exposure in the outside atmosphere. 3.3. If egg deposits are made in the culture dishes immediately following exposure in the outside atmosphere, mold colonies will develop very slowly. However, they will disappear soon after the larvae make their appearance. 4.4. The larvae are capable of destroying some mold colonies 4 days old. 5.5. There are variations in the resisting powers of the different molds studied. Some prevent development of larvae completely. 6.6. Several of the molds have definite effects on the life span of the mature flies. Some kill the flies as early as the fourth day. 7.7. The larvae, molds, and larvae-mold growths cause changes in the hydrogen-ion concentration of the medium.
Seasonal reversals of upland‐riparian diversity gradients in the Sonoran Desert

Flood disturbance and water resource availability vary sharply over time and space along arid-region rivers and can interact in complex fashion to shape diversity patterns. Plant diversity showed spatial patterning along a topogradient from the floodplain of the San Pedro River (Arizona, USA) to the arid upland, but the patterns shifted temporally as the suite of limiting factors changed. During two of three sampling times, spatial diversity patterns were shaped primarily by gradients of water availability, the regional limiting factor. In the summer dry season, microscale diversity (species richness per 1 m 2 ) and mesoscale diversity (cumulative species and functional types in 20, 1-m 2 plots) of herbaceous plants decreased along the topogradient from floodplain to upland, reflecting the greater water availability on the low surfaces. During a summer wet season with moderate rains and flooding, diversity increased in all hydrogeomorphic zones (floodplain, terrace, upland), but the spatial pattern along the topogradient persisted. Following a very wet winter, patterns along the topogradient reversed: scour from large floods limited diversity on the floodplain and competitive exclusion limited the diversity on undisturbed river terrace, while abundant rains allowed for high microscale diversity in the upland. Disturbance and resource availability thus interacted to influence plant species diversity in a fashion consistent with the dynamic-equilibrium model of species diversity. In contrast to the microscale patterns, mesoscale diversity of species and functional types remained high in the floodplain during all sampling times, with 58% more plant species and 90% more functional types sampled in low floodplain than arid upland for the year as a whole. Species with a wide range of moisture and temperature affinities were present in the floodplain, and seasonal turnover of species was high in this zone. The floodplain zone of a perennial to intermittent-flow river thus had greater plant diversity than arid Sonoran Desert upland, as measured at temporal scales that capture seasonal variance in resource and disturbance pulses and at spatial scales that capture the environmental heterogeneity of floodplains. Although periodically limited by intense flood disturbance, diversity remains high in the floodplain because of the combination of moderate resource levels (groundwater, seasonal flood water) and persistent effects of flood disturbance (high spatial heterogeneity, absence of competitive exclusion), in concert with the same climatic factors that produce seasonally high diversity in the region (temporally variable pulses of rainfall).
A multiscale finite element formulation for axisymmetric elastoplasticity with volumetric locking

Similar to plane strain, axisymmetric stress problem is also highly kinematics constrained. Standard displacement-based finite element exhibits volumetric locking issue in simulating nearly/fully incompressible material or isochoric plasticity under axisymmetric loading conditions, which severely underestimates the deformation and overestimates the bearing capacity for structural/geotechnical engineering problems. The aim of this paper is to apply variational multiscale method to produce a stabilized mixed displacement–pressure formulation, which can effectively alleviate the volumetric locking issue for axisymmetric stress problem. Both nearly incompressible elasticity and isochoric J2 elastoplasticity are investigated. First-order 3-node triangular and 4-node quadrilateral elements are tested for locking issues. Several representative simulations are provided to demonstrate the performance of the linear elements, which include the convergence study and comparison with closed-form solutions. A comparative study with pressure Laplacian stabilized formulation is also presented. Copyright © 2009 John Wiley & Sons, Ltd.
Measurement of small angle fiber misalignments in continuous fiber composites

Abstract In aligned, continuous fiber composites the fibers actually wander with small angular misalignments about the mean direction. These misalignments are suspected of having a significant influence on several mechanical properties, such as longitudinal compression strength and tensile modulus. A technique is presented for measuring the volume fraction distribution of fiber misalignment angle in the range of ±10° , with an estimated resolution of ±0·25° . The method can provide a full bivariate distribution, which includes both in-plane and out-of-plane misalignments. Data from a carbon fiber composite, APC-2, are given as an illustration. Misalignment distributions for prepreg, a 0/90 laminate, and a unidirectional laminate are given. It is found that the distribution in the prepreg is axially symmetric, but changes upon laminations, the changes depending on stacking sequence. In this particular material most of the fibers are found to lie within ±3° of the mean fiber direction. Distribution standard deviations range from 0·693 to 1·936 degrees.
Clinical Trials from Close Up

Between Bench and Bedside. Science, Healing, and Interleukin-2 in a Cancer Ward. ILANA LOWY. Harvard University Press, Cambridge, MA, 1996. vi, 370 pp., illus. $39.95 or £26.50. ISBN 0-674-06809-2.
Depolarization and emittance degradation effects associated with charge transfer in a magnetic field

Abstract The effects on beam emittance and polarization which result from charge-transfer collisions within a magnetic field region are quantitatively discussed. The minimum magnetic field strength required to prevent depolarization under various circumstances is given. It is concluded that the Lamb-shift type of polarized-ion source has significant advantages over conventional polarized-ion sources if negative ions are required.
Neurogenic responses to amyloid-beta plaques in the brain of Alzheimer's disease-like transgenic (pPDGF-APPSw,Ind) mice

Formation and accumulation of amyloid-beta (A beta) plaques are associated with declined memory and other neurocognitive function in Alzheimer's disease (AD) patients. However, the effects of A beta plaques on neural progenitor cells (NPCs) and neurogenesis from NPCs remain largely unknown. The existing data on neurogenesis in AD patients and AD-like animal models remain controversial. For this reason, we utilized the nestin second-intron enhancer controlled LacZ (pNes-LacZ) reporter transgenic mice (pNes-Tg) and Bi-transgenic mice (Bi-Tg) containing both pPDGF-APPSw,Ind and pNes-LacZ transgenes to investigate the effects of A beta plaques on neurogenesis in the hippocampus and other brain regions of the AD-like mice. We chose transgenic mice at 2, 8 and 12 months of age, corresponding to the stages of A beta plaque free, plaque onset and plaque progression to analyze the effects of A beta plaques on the distribution and de novo neurogenesis of (from) NPCs. We demonstrated a slight increase in the number of NPCs in the hippocampal regions at the A beta plaque free stage, while a significant decrease in the number of NPCs at A beta plaque onset and progression stages. On the other hand, we showed that A beta plaques increase neurogenesis, but not gliogenesis from post-mitotic NPCs in the hippocampus of Bi-Tg mice compared with age-matched control pNes-Tg mice. The neurogenic responses of NPCs to A beta plaques suggest that experimental approaches to promote de novo neurogenesis may potentially improve neurocognitive function and provide an effective therapy for AD.
Reality is broken to be rebuilt: how a gamer’s mindset can show science educators new ways of contribution to science and world?

This paper presents a review of Jane McGonigal’s book, “Reality is broken” (Reality is broken: why games make us better and how they can change the world. Penguin Press, New York, 2011). As the book subtitle suggests it is a book about “why games make us better and how they can change the world”, written by a specialist in computer game design. I will try to show the relevance this book might have to science educators through emphasizing the points that the author offers as the fixes to rebuild reality on the image of gaming world. Using cultural-historical activity theory, I will explore how taking up a gamer mindset can challenge one to consider shortcomings in current approaches to the activity of teaching–learning science and how using this mindset can open our minds to think of new ways of engaging in the activity of doing science. I hope this review will encourage educators to explore the worldview presented in the book and use it to transform our thinking about science education.
Dipole stabilized a-amino carbanions. III. Metalation-alkylation of indolines, tetrahydroquinolines and n-methylanilines.

Abstract Metalation of the 2-position in indolines and tetrahydroquinolines is feasible via their fomamidine derivatives using tert -butyllithium. The N-methyl group in N-methylanilines is also metalated using this base.
DEVELOPMENT OF THE YOUNG WHEAT SPIKE: A SEM STUDY OF CHINESE SPRING WHEAT

The number of leaves on the main culm was correlated with morphological changes in the wheat spike during development, up to the terminal spikelet stage. The developmental changes were divided into nine stages, which were compared with stages described by other investigators. Several environmental conditions were utilized to determine the consistency of morphological correlations. Although the different environments did influence the length of time required to reach the various stages, the relationship between leaf number and stage of spike development was consistent. Regardless of environmental conditions, all stages were evident. Vernalization period affected the number of spikelets. Plants vernalized 6 wk produced 17-19 spikelets7 compared to 21-24 spikelets on plants vernalized 3 wk. There were three major morphological events dunng spike development: 1) the change from vegetative to reproductive growth, 2) lateral spikelet development, and 3) the initiation and development of the terminal spikelet.
Temperature and duration effects on microstructure evolution during copper wafer bonding

Interfacial morphologies during Cu wafer bonding at bonding temperatures of 300–400°C for 30 min followed by an optional 30-min or 60-min nitrogen anneal were investigated by means of transmission electron microscopy (TEM). Results showed that increased bonding temperature or increased annealing duration improved the bonding quality. Wafers bonded at 400°C for 30 min followed by nitrogen annealing at 400°C for 30 min, and wafers bonded at 350°C for 30 min followed by nitrogen annealing at 350°C for 60 min achieve the same excellent bonding quality.
The Promise of Micro-Enterprise: Understanding Individual and Organizational Impacts

With the current state of American politics polarized into red and blue states, policy agreement between Republicans and Democrats, or conservatives and liberals seems difficult to imagine. Yet in the 1990s, policies for micro-enterprise and micro-credit were heralded by both conservatives and liberals as "silver bullets" for addressing poverty and promoting economic development in low-income communities. Inspired by success in developing countries, such as the widely publicized Grameen Bank in Bangladesh, micro-enterprise programs (MEPs) were started in the U.S. to assist low-income entrepreneurs in starting a micro-enterprise. MEPs use tools like micro-credit (small business loans) and technical support to foster micro-enterprises-very small businesses, typically soleproprietorships, small partnerships, or family businesses with fewer than five employees and annual sales of $250,000 or less (Self-Employment Learning Project 1994; Walker and Blair 2002). MEPs certainly appear to offer a novel approach to old problems. At the macro-level, MEPs offer a new organizational approach to economic development. At the micro-level, MEPs are an innovative means to poverty alleviation in low-income households by offering individuals access to loans to start businesses that can provide income. MEPs appeal to conservatives by encouraging self-reliance, individual responsibility, and support for the private sector through business-ownership. In contrast, they appeal to liberals for providing economic resources directly to poor individuals. In the mid to late 1990s, it appeared that MEPs were the bipartisan answer to economic development in depressed areas. MEPs have received much attention from developmental economists who evaluate their impact in developing countries (e.g., Stiglitz 1990; Besley and Coate 1995; Yunus 1999). Fewer systematic studies of micro-enterprise in the United States exist, however, where unlike developing countries, very small and informal businesses are much less likely to produce economic returns great enough to support individuals and families. Two recent books on micro-enterprise begin to fill this gap. Kitchen Capitalism by Sherraden, Sanders, and Sherraden (SSS) uses primarily qualitative interview data, but also longitudinal quantitative data, to analyze the impact of micro-enterprise in low-income households. At the macro-level, Taub analyzes the history and impact of the Southern Development Bancorporation (Southern), an MEP operating in southern Arkansas, one of the poorest regions of one of the poorest states in the United States.
Catalytic conversion of nitrogen to ammonia by an iron model complex

Threefold symmetric Fe phosphine complexes have been used to model the structural and functional aspects of biological N2 fixation by nitrogenases. Low-valent bridging Fe-S-Fe complexes in the formal oxidation states Fe(II)Fe(II), Fe(II)/Fe(I), and Fe(I)/Fe(I) have been synthesized which display rich spectroscopic and magnetic behavior. A series of cationic tris-phosphine borane (TPB) ligated Fe complexes have been synthesized and been shown to bind a variety of nitrogenous ligands including N2H4, NH3, and NH2 - . These complexes are all high spin S = 3/2 and display EPR and magnetic characteristics typical of this spin state. Furthermore, a sequential protonation and reduction sequence of a terminal amide results in loss of NH3 and uptake of N2. These stoichiometric transformations represent the final steps in potential N2 fixation schemes. Treatment of an anionic FeN2 complex with excess acid also results in the formation of some NH3, suggesting the possibility of a catalytic cycle for the conversion of N2 to NH3 mediated by Fe. Indeed, use of excess acid and reductant results in the formation of seven equivalents of NH3 per Fe center, demonstrating Fe mediated catalytic N2 fixation with acids and protons for the first time. Numerous control experiments indicate that this catalysis is likely being mediated by a molecular species. A number of other phosphine ligated Fe complexes have also been tested for catalysis and suggest that a hemi-labile Fe-B interaction may be critical for catalysis. Additionally, various conditions for the catalysis have been investigated. These studies further support the assignment of a molecular species and delineate some of the conditions required for catalysis. Finally, combined spectroscopic studies have been performed on a putative intermediate for catalysis. These studies converge on an assignment of this new species as a hydrazido(2-) complex. Such species have been known on group 6 metals for some time, but this represents the first characterization of this ligand on Fe. Further spectroscopic studies suggest that this species is present in catalytic mixtures, which suggests that the first steps of a distal mechanism for N2 fixation are feasible in this system.
Therapeutic Temperature Modulation for Fever After Intracerebral Hemorrhage

Background We sought to determine whether therapeutic temperature modulation (TTM) to treat fever after intracerebral hemorrhage (ICH) is associated with improved hospital complications and discharge outcomes.
New insights for self-assembled monolayers of organothiols on Au(111) revealed by scanning tunneling microscopy

In the past decade, scanning tunneling microscopy (STM) has revealed new information regarding self-assembled monolayers (SAMs) of organothiols on Au(111) at the molecular level. The periodicity, defects, morphology, and various phases during the self-assembly process have been visualized with unprecedented detail. Using STM under ultrahigh vacuum, new insights regarding SAMs have been revealed from the perspective of potential applications in molecular devices. This article focuses on a molecular-level understanding of the formation of adatom and vacancy islands and reveals how the structure is impacted by introducing aromatic termini. The thermal stability and thermally induced structural evolution of SAMs are monitored in situ. The behavior of alkanethiol molecules under local electric field and tunneling current are studied with molecular resolution. Molecular-level insight regarding negative differential resistance of SAMs is also discussed.
Radial glia in the human fetal cerebrum: a combined Golgi, immunofluorescent and electron microscopic study.

Abstract Golgi techniques, immunofluorescence for glial fibrillary acidic (GFA) protein, and electron microscopy (EM) were used to determine the nature of radial glia in the cerebrum of human fetuses ranging from 7 to 20 weeks of ovulation age. Successful Golgi impregnation of radial fibers was achieved in fetuses 12 weeks of age and older. These fibers spanned the entire thickness of the hemisphere. At the pial surface many of them branched and terminated in pyramidal end feet expansions. Indirect immunofluorescent preparations utilizing antiserum to GFA protein, a protein specific for astrocytes, demonstrated numerous radially oriented nearly parallel fluorescent fibres between the ventricular zone and pia mater. GFA protein-positive fibers were demonstrated in all fetal specimens examined with this technique (10 weeks of age and older). Along the outer border of the marginal zone they formed a horizontal GFA protein-containing subpial membrane. By EM there were numerous linear electron lucent astrocytic processes containing 8–9 nm filaments and occasional glycogen granules at all levels of the cerebrum. They were interspersed among smaller and darker neuronal processes containing 20–25 nm neurotubules, and were demonstrable at all fetal ages between 7 and 18 weeks. They formed pericapillary investments and subpial terminal expansions closely abutting basal lamina of pia mater in every specimen examined. On the basis of these combined analyses, we conclude that radial glial fibers in early human fetal cerebrum represent processes of immature astrocytes. Although subsequently undergoing further maturation, radial glia already possess fundamental immunocytochemical and morphological characteristics indicative of astrocytic differentiation. A significant implication of our findings is that the development of astrocytes in the human fetal brain occurs much earlier than formerly believed.
Structure and gene-polypeptide relationships of the region encoding glycerol diffusion facilitator (glpF) and glycerol kinase (glpK) of Pseudomonas aeruginosa.

The glycerol facilitator is one of the few known examples of bacterial solute transport proteins that catalyse facilitated diffusion across the cytoplasmic membrane. A second protein, glycerol kinase, is involved in entry of external glycerol into cellular metabolism by trapping glycerol in the cytoplasm as sn-glycerol 3-phosphate. Evidence is presented that glycerol transport in Pseudomonas aeruginosa is mediated by a similar transport system. The genes encoding the glycerol facilitator, glpF, and glycerol kinase, glpK, were isolated on a 4.5 kb EcoRI fragment from a chromosomal mini-library by functional complementation of an Escherichia coli glpK mutant after establishing a map of the chromosomal glpFK region with the help of a PCR-amplified glpK segment. The nucleotide sequence revealed that glpF is the promoter-proximal gene of the glpFK operon. The glycerol facilitator and glycerol kinase were identified in a T7 expression system as proteins with apparent molecular masses of 25 and 56 kDa, respectively. The identities of the glycerol facilitator and glycerol kinase amino acid sequences with their counterparts from Escherichia coli were 70 and 81%, respectively; this similarity extended to two homologues in the genome sequence of Haemophilus influenzae. A chromosomal δglpFK mutant was isolated by gene replacement. This mutant no longer transported glycerol and could no longer utilize it as sole carbon and energy source. Two ORFs, orfX and orfY, encoding a putative regulatory protein and a carbohydrate kinase of unknown function, were located upstream of the glpFK operon.
Nucleotide sequence of the Staphylococcus aureus signal peptidase II (lsp) gene

The lsp gene encoding prolipoprotein signal peptidase (signal peptidase II) of Staphylococcus aureus was cloned by screening a genomic library for plasmid clones capable of complementing a conditionally lethal lsp allele of Escherichia coli, E. coli cells carrying one of five overlapping clones exhibited increased resistance to globomycin. The nucleotide sequence of the S. aureus lsp gene was determined. The deduced amino acid sequence of the signal peptidase II of S. aureus suggests that this enzyme has a hydropathy profile very similar to those of E. coli, Enterobacter aerogenes and Pseudomonas fluorescens. Comparison of the primary structures of this enzyme from these four distinct bacterial species reveals three highly conserved domains in proteins which have a low degree of overall sequence homology. Unlike the lsp genes from the Gram-negative bacteria, the lsp gene in S. aureus is not flanked by x-ileS and orf149-orf316 as found in E. coli, Ent. aerogenes, and P. fluorescens.
Mineralizable soil nitrogen and labile soil organic matter in diverse long-term cropping systems

Sustainable soil fertility management depends on long-term integrated strategies that build and maintain soil organic matter and mineralizable soil N levels. These strategies increase the portion of crop N needs met by soil N and reduce dependence on external N inputs required for crop production. To better understand the impact of management on soil N dynamics, we conducted field and laboratory research on five diverse management systems at a long-term study in Maryland, the USDA- Agricultural Research Service Beltsville Farming Systems Project (FSP). The FSP is comprised of a conventional no-till corn (Zea mays L.)–soybean (Glycine max L.)–wheat (Triticum aestivum L.)/double-crop soybean rotation (NT), a conventional chisel-till corn–soybean–wheat/soybean rotation (CT), a 2 year organic corn–soybean rotation (Org2), a 3 year organic corn–soybean–wheat rotation (Org3), and a 6 year organic corn–soybean–wheat–alfalfa (Medicago sativa L.) (3 years) rotation (Org6). We found that total potentially mineralizable N in organic systems (average 315 kg N ha−1) was significantly greater than the conventional systems (average 235 kg N ha−1). Particulate organic matter (POM)–C and –N also tended to be greater in organic than conventional cropping systems. Average corn yield and N uptake from unamended (minus N) field microplots were 40 and 48%, respectively, greater in organic than conventional grain cropping systems. Among the three organic systems, all measures of N availability tended to increase with increasing frequency of manure application and crop rotation length (Org2 < Org3 ≤ Org6) while most measures were similar between NT and CT. Our results demonstrate that organic soil fertility management increases soil N availability by increasing labile soil organic matter. Relatively high levels of mineralizable soil N must be considered when developing soil fertility management plans for organic systems.
Estrogen target cells in the pituitary of platyfish, Xiphophorus maculatus.

The distribution of estradiol-concentrating cells in the pituitary of the platyfish, Xiphophorus maculatus, is studied after the injection of 3H estradiol-17β by thaw-mount autoradiography. Autoradiograms prepared 2–8 h after the injection show nuclear concentration of radioactivity in certain cells of the proximal pars distalis, while no nuclear labeling is found in cells of the rostral pars distalis, pars intermedia and pars nervosa. Radioactively labeled cells are identified as gonadotropes by a combined technique of thaw-mount autoradiography and immunoperoxidase staining with antiserum to ovine LH. Approximately 80% of the immunoreactive LH cells show a concentration of radioactivity in their nuclei. These observations indicate that in teleosts, as in mammals, estradiol has a direct effect on pituitary gonadotropes.
Oxidative metabolism of Euglena.

Abstract The metabolic behavior of intact and disrupted Euglena cells is consistent with the hypothesis that oxidative metabolism of Euglena occurs via the Krebs cycle, and that impermeability of the Euglena cell membrane to many organic acid anions limits the availability of such compounds as carbon and energy sources for intact Euglena .
Mutagenicity of the triazine herbicides atrazine, cyanazine, and simazine in Drosophila melanogaster.

Assays for dominant lethal mutations, sex‐linked recessive lethal mutations, and chromosomal breakage, nondisjunction and loss were performed on Drosophila melanogaster males treated by injection or by larval feeding of the herbicides atrazine (2‐chloro‐4‐ethylamino‐6‐isopropylamino‐1,3,5‐triazine), cyanazine [2‐chloro‐4‐(1‐cyano‐1‐methylethylamino)‐6‐ethylamino‐1,3,5‐triazine], or simazine [2‐chloro‐4,6‐bis‐(ethylamino)‐1,3,5‐triazine]. The three herbicides significantly increased the rate of apparent dominant lethals, but this reduction in egg hatch was probably due to physiologic toxicity to sperm. Atrazine significantly increased X‐linked recessive lethals and X or Y loss after treatment by larval feeding. Injection of simazine elevated X‐linked lethals, whereas treatment by larval feeding did not. None of these herbicides significantly increased partial loss of the Y chromosome nor sex chromosome nondisjunction. Much larger experiments are needed to determine with confidence the mutagenic potential o...
Room temperature oxidation rate constants of ultra- thin (discontinuous) molybdenum films

Abstract Following the method developed by Fehlner, an attempt is made to determine the room temperature oxidation rate constants of ultra-thin (discontinuous) molybdenum films. Thin films of molybdenum of thickness less than 100 A, corresponding to resistance of 0.55–12.0 Mω, were deposited onto glass substrates at pressures of less than 10−8 Torr and were exposed to oxygen pressures of 10−7−10−5 Torr at room temperature. The oxidation rate constants were calculated from the slope of log Rdcversus log t plots using the electron tunneling conduction model of Neugebauer and Webb. Values of the logarithmic oxidation rate constants obtained ((0.05−0.18) × 10−9 cm) are compared with those for various refractory metal films and agree fairly well with those published in the literature for discontinuous metal films.
The disintegration of the state model in the English speaking Caribbean: Restructuring and redefining public service broadcasting

Public service broadcasting evolved in the small states of the English speaking Caribbean as state broadcasting. As such, state broadcasting has been forced to change to compete with private broadc...
Dynamics of surface thermal expansion and diffusivity using two-color reflection transient gratings

We report ultrafast measurements of the dynamic thermal expansion of a surface and the temperature dependent surface thermal diffusivity using a two-color reflection transient grating technique. Studies were performed on p-type, n-type, and undoped GaAs(100) samples at several temperatures. Using a 75 fs ultraviolet probe with visible excitation beams, the electronic effects that dominate single color experiments become negligible; thus surface expansion due to heating and the subsequent contraction caused by cooling provide the dominant influence on the diffracted probe. The diffracted signal was composed of two components, thermal expansion of the surface and heat flow away from the surface, allowing the determination of the rate of expansion as well as the surface thermal diffusivity. At room temperature a signal rise due to thermal expansion was observed, corresponding to a maximum average displacement of approximately equals 1 angstroms at 32 ps. Large fringe spacings were used, thus the dominant contributions to the signal were expansion and diffusion perpendicular to the surface. Values for the surface thermal diffusivity of GaAs were measured and found to be in reasonable agreement with bulk values above 50 degree(s)K. Below 50 degree(s)K, the diffusivity at the surface was more than an order of magnitude slower than in the bulk due to increased phonon boundary scattering. Comparison of the results with a straightforward thermal model yields good agreement over a range of temperatures (12 - 300 degree(s)K). The applicability and advantages of the transient grating technique for studying photothermal and photoacoustic phenomena are discussed.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Barriers to internal rotation, vibrational assignment, and ab initio calculations for chloroacetyl chloride

Abstract The infrared spectra (3600–30 cm −1 ) of gas and solid chloroacetyl chloride, ClCH 2 C(O)Cl, and the Raman spectra (3600–10 cm −1 ) of the gas, liquid with qualitative depolarization, and solid have been recorded. From studies of the Raman spectra at variable temperatures the energy difference between the low-energy trans and high-energy gauche conformers has been found to be 501 ± 145 cm −1 (1.43 ± 0.4 kcal/mol) and 655 ± 29 cm −1 (1.87 ± 0.08 kcal/mol) for the gaseous and liquid phases, respectively. The potential function governing internal rotation of the asymmetric top has been determined from the observed torsional transitions in the far infrared spectrum and the potential constants are: V 1 = 438 ± 16, V 2 = 278 ± 8, V 3 = 557 ± 1, V 4 = 67 ± 2 and V 6 = 6 ±cm −1 . The trans to gauche, gauche to gauche, and gauche to trans barriers are 944, 408, and 357 cm −1 respectively. This potential function is consistent with an enthalpy difference of 587 ± 25 cm −1 (1.68 ± 0.1 kcal/mol) and a torsional dihedral angle for the gauche conformer of 118°. The asymmetric potential function, conformational energy difference, and optimized geometries of both conformers have also been obtained from ab initio calculations at both the 3-21G* and 6-31G* basis set levels. A normal coordinate analysis has also been performed with a force field determined from the 3-21G* basis set level calculation. These results are compared to corresponding quantities for some similar molecules.
Microstructural evaluation of optical materials and devices using a combination of focused ion beam sputtering and transmission electron microscopy

Abstract I describe how the application of focused ion beam (FIB) sputtering can substantially enhance the role of transmission electron microscopy (TEM) in microstructural study of optical materials and devices. The primary new capabilities of the FIB-TEM combination are site-specific selection with nanoscale positional accuracy, simultaneous thinning of materials with very different sputtering rates, deconvolution of nanoscale stress fields, and nanoscale dopant mapping in InP-based structures.
A Fully-Compliant, In-Plane Rotary, Bistable Micromechanism

A fully compliant bistable micromechanism (hereafter identified as an in-plane rotary bistable micromechanism or IPRBM) is designed to accomplish in-plane rotary motion with two stable positions. The micromechanism consists of four individually bistable mechanisms arranged in a cyclically symmetric geometry about a central proof mass. This class of bistable mechanism can be used in gate valve, optical shutter, and other switching applications. Two classes of IPRBMs are investigated in this paper. The bistable micromechanism size is less than 1 mm and fabricated by electroplating a soft magnetic material — Permalloy (80% Ni, 20% Fe) in a positive photoresist mold. Minimum feature size in the IPRBM, which corresponds to the width of flexible linkages, is 4 μm. The fabricated IPRBMs have been tested for their force-deflection response using an image based force sensing method. The test results were then compared with the simulated results obtained from a finite element model of the IPRBM. The IPRBM are shown to reversibly undergo 10 to 20 degrees of in-plane rotation and required a maximum torque of 1 to 2 μNm depending on the design. The experimental results showed good overall agreement with the design. A comparison within and between the two classes of IPRBM have been completed for three different design cases between which the tether width and aspect ratio was varied. The study showed a relative advantage of slender tethers with high aspect ratio in minimizing out-of-plane deflection. Also, the radial separation of the individual bistable mechanisms is important.Copyright © 2005 by ASME
Multiple brain tumor nodule resections under direct visualization of a neuronavigated endoscope.

Background With neuronavigation-assistance, endoscopic neurosurgery has a variety of advantages for brain tumor resection. However, intraoperative neuronavigation has to be operated by frequently alternating a neuronavigation wand and moving the microscope back-and-forth on the surgical field while the microscope is being used for surgery, except when using stereo overlays in the operating microscope aligned to the operative scene. In our practice, our surgical endoscope was used as a sole optical device and was also calibrated as a virtual wand targeting to tumor nodules while the operation was being performed under its simultaneous visualization. This paper gives a brief description and technical report of applications of image-guided endoscopy in two cases with multiple tumor nodules. Methods A 0-degree, 4-mm rigid endoscopes (DCI; Storz and Co., Tuttlingen, Germany) and Voyager SX navigation system by Z-KAT (Marconi, USA) were used for both cases, a 32-year-old woman with multiple hemangioblastomas and a 46-year-old man with two recurrent astrocytomas. The endoscope has a digital video output, which was registered with reference calibration for rendered image-guided stereoscopic views. The neuronavigation screen was formatted to provide axial, coronal, and sagittal magnetic resonance (MR) images demonstrating the location and trajectory of the endoscope's tip. Endoscope angles of 0 degrees and 30 degrees were used interchangeably during surgery. For both posterior fossa tumors, an entry point on the skull was identified using "virtual endoscopy" to visualize the intracranial anatomy and lesions. Results A 3-cm linear skin incision for both cases was made at the entry point guided by the endoscope's video output and a 3-dimensional (3-D) rendered image on the navigation system. Three tumor nodules in the first patient, and two nodules in the second, were removed directly under navigated-endoscopic visualization on one monitor with 3D imaging-guidance images on the other side-by-side. Conclusion The neuronavigated endoscope coordinates of the tip of endoscope, and the trajectory of targets, provide both 3D orientation and direct endoscopic visualization simultaneously, and present with the unique feature for solely endoscopic minimally invasive procedures, especially for multiple intracranial lesions.