cssi/SciSciGPT-SciSciNet huggingface dataset:
Semiconductor to topological insulator transition induced by stress propagation in metal dichalcogenide core-shell lateral heterostructures.

Polymorphic phase transitions are an important route for engineering the properties of two-dimensional materials. Heterostructure construction, on the other hand, not only allows the integration of different functionalities for device applications, but also enables the exploration of new physics arising from proximity coupling. Yet, implementing a design that incorporates the advantages of both remains underexplored. Here, based on comprehensive experimental and theoretical studies of the WSe2/SnSe2 core–shell lateral heterostructure, we demonstrate an unexpected H to T′ phase transition in transition metal dichalcogenides (TMDs), correlating with a change of the material properties from a semiconductor to a topological insulator (TI), and propose a novel shell-to-core stress propagation mechanism. This finding offers new insights into TMD phase transitions empowered by the rational design of heterostructures. Owing to the superconducting properties of SnSe2 at low temperatures, the unique TI/superconductor core–shell template is expected to add to the arsenal in the ongoing search for Majorana fermions in condensed matter systems.
A Dynamic Hyperbolic Surface Model for Responsive Data Mining

Abstract Data management systems impose structure on data via a static representation schema or data structure. Information from the data is extracted by executing queries based on predefined operators. This paradigm restricts the searchability of the data to concepts and relationships that are known or assumed to exist among the objects. While this is an effective and efficient means of retrieving simple information, we propose that such a structure severely limits the ability to derive breakthrough knowledge that exists in data under the guise of “unknown unknowns.” A dynamic system will alleviate this dependence, allowing theoretically infinite projections of the data to reveal discoverable relationships that are hidden by traditional use case-driven, static query systems. In this paper, we propose a framework for a data-responsive query algebra based on a dynamic hyperbolic surface model. Such a model could provide more intuitive access to analytics and insights from massive, aggregated datasets than existing methods. This model will significantly alter the means of addressing the underlying data by representing it as an arrangement on a dynamic, hyperbolic plane. Consequently, querying the data can be viewed as a process similar to quantum annealing, in terms of characterizing data representation as an energy minimization problem with numerous minima.
Open questions on physical chemistry of crystal growth from congruent melts

Crystallization is observed in both nature and in the lab, and is critical to diverse areas of science and technology. Here, the author summarizes the theories that have been proposed to explain crystal growth from melts, and raises some open questions that remain. Crystallization is observed in both nature and in the lab, and is critical to diverse areas of science and technology. Here, the author summarizes the theories that have been proposed to explain crystal growth from melts, and raises some open questions that remain.
Developmental biology: A 5'Hoxd-Gli3 balance in tetrapod axial polarity

Almost all living tetrapods exhibit postaxial dominance in digit formation, apart from urodele amphibians, which show preaxial dominance. Recent work shines light on the genetic differences between the two modes of limb development, suggesting that differences in 5'Hoxd expression, mediated by Gli3, may explain the switch in axial polarity.
Onate's Expedition To the Southern Plains: Routes, Destinations, and Implications for Late Prehistoric Cultural Adaptations

This article reassesses the route and destination of Onate’s 1601 expedition to the Southern Plains. It also reconsiders a recent discussion of a map drawn by an indian who was captured during the ...
The Asparagine Synthetase of Escherichia coli I. BIOSYNTHETIC ROLE OF THE ENZYME, PURIFICATION, AND CHARACTERIZATION OF THE REACTION PRODUCTS

Abstract Synthesis of l-asparagine was detected in extracts of Escherichia coli K-12 only under conditions where either the amount of asparaginase II was greatly lowered or else its activity was inhibited by 5-diazo-4-oxo-l-norvaline (DONV). Asparagine synthetase, the enzyme responsible for the formation of the amino acid, was lacking in extracts of an auxotrophic mutant which required asparagine. Asparagine repressed the formation of the synthetase, but at a rather high concentration, possibly because asparagine is not readily concentrated by the bacterial cell. A genetic locus for the production of asparagine synthetase (for which we propose the name asn) was found to be between the 73rd and 74th min of the E. coli chromosome by conjugation and transduction experiments. Asparagine synthetase was purified 370-fold from a mutant of E. coli impaired in its ability to form asparaginase II. In order to diminish the amount of residual asparaginase further, extracts were made of this mutant after it was osmotically shocked. The synthetase had a molecular weight of about 80,000; it was stabilized by 2-mercaptoethanol and by 10% glycerol. The synthesis of asparagine required aspartate, ATP-Mg2+, and ammonia, and resulted in the stoichiometric production of pyrophosphate and AMP. Glutamine did not serve as a source of amide nitrogen. The pH optimum was 8.4. The enzyme preparation, shown to be free of aspartyl transfer RNA synthetase, in the absence of added ammonia also catalyzed an aspartate-dependent pyrophosphate exchange with ATP, which was inhibited by asparagine. β-Aspartyl hydroxamate was formed in incubations with hydroxylamine.
A PLAUSIBLE HISTORY AND EXPLORATION OF STEVENSON’S DEFINITION OF ENTREPRENEURSHIP

Entrepreneurship scholarship, with opportunity as its defining characteristic, would benefit from an appraisal of Howard Stevenson’s (1983) definition that “Entrepreneurship is the process by which individuals pursue opportunities without regard to the resources they currently control.” We analyze three stories from Allen (2001) to generate insights into Stevenson’s view that opportunities require both desirability and feasibility and we provide a theoretical framework for how individuals go about generating resources to pursue opportunity, and vice versa. We point out situations where resources, at hand, lead to opportunities, and where imagination reconfigures both resources and opportunities into viable businesses.
A Mathematical Model of Ethanol Fermentation from Cheese Whey

The cybernetic approach to modeling of microbial kinetics in a mixed-substrate environment has been used in this work for the fermentative production of ethanol from cheese whey. In this system, the cells grow on multiple substrates and generate metabolic energy during product for­mation. This article deals with the development of a mathematical model in which the concept of cell maintenance was modified in light of the spe­cific nature of product formation. Continuous culture data for anaerobic production of ethanol by Kluyveromyces marxianus CBS 397 on glucose and lactose were used to estimate the kinetic parameters for subsequent use in predicting the behavior of microbial growth and product forma­tion in new situations.
Convergence of regularized, renormalized perturbation series for super-renormalizable field theories

It is shown for the two-dimensional scalar Yukawa interaction, that the renormalized perturbation series has at least a finite radius of convergencewhen regularized (cut-off in space-time and momentum space). This is accomplished by writing down the explicit renormalized series, studying some of its associated combinatorics, and applying Caianiello’s standard arguments on the unrenormalized series (16). The result extends to any super-renormalizable theory of the\(\varphi \bar \psi \psi \) form.
On the application of 4-hydroxybenzoic acid as a trapping agent to study hydroxyl radical generation during cerebral ischemia and reperfusion

Aromatic hydroxylation from the reaction between hydroxyl radical and salicylate or its related compounds has been often utilized as a marker for the generation of hydroxyl radicals. We have investigated several technical aspects of applying this method to study hydroxyl radical production during cerebral ischemia and reperfusion using the hydroxylation of 4-hydroxybenzoic acid (4-HBA) to form 3,4-dihydroxybenzoic acid (3,4-DHBA). 4-HBA was administered to rats either through intravenous infusion, or by way of an in vivo microdialysis probe implanted in the brain. Dialysate containing 3,4-DHBA was collected and analyzed by HPLC with electrochemical detection. An endogenous compound was found to co-elute with 3,4 -DHBA but could be separated by varying the chromatographic conditions. Because of interrupted blood flow during cerebral ischemia and reperfusion, delivery of 4-HBA through the microdialysis probe is a preferred method to systemic administration such as intravenous infusion. It is concluded that the oxidation of 4-HBA to 3,4-DHBA can be a reliable and accurate indicator for the formation of hydroxyl radical in vivo if the experiments are well designed to avoid potential pitfalls associated with technical difficulties of the method.
The processing graph method tool (PGMT)

To acquire stare-of-the-art hardware at reduced cost, the U.S. Navy is committed to buying commercial off the shelf (COTS) computer hardware. In this rapidly changing technological world, today's hardware will be obsolete tomorrow. The Navy's complex problems often require more computational power than can be delivered by a single serial processor. The solution lies in distributed processing. However, distributed processors tend to have architecture specific languages, requiring an expensive and time-consuming manual rewrite of application software as new technology and new machines become available. The processing graph method (PGM), developed at the Naval Research Laboratory (NRL) in Washington, DC, is an architecture independent method for specifying application software for distributed architectures. Its model of computation is reconfigurable dynamic data flow: dynamic because the amount of data consumed and produced by an actor may vary from one firing to another; and reconfigurable, because a graph may be disassembled and reassembled. PGM was implemented on the Navy Standard Signal Processor (AN/UYS-2), and on VAX and Sun workstations. The PGMT project at NRL is developing a tool set that will facilitate the implementation of PGM on a given distributed architecture at relatively low cost. We describe the major features PGM and discuss the PGMT project.
A Method for Proving Lower Bounds for Certain Geometric Problems

We prove lower bounds for a number of geometric problems. Our results show that certain types of additional input information cannot possibly permit faster solutions for these problems. The main idea in all our lower bound proofs is the use of the index of a point as an additional coordinate.
Oxidized low density lipoproteins alter macrophage lipid uptake, apoptosis, viability and nitric oxide synthesis.

Uptake of oxidized low density lipoproteins (LDL) by monocyte macrophages to form "foam" cells occurs during formation of atherosclerotic lesions. Inducible nitric oxide synthase (iNOS) has been identified in foam cells. To investigate interactions between oxidized LDL, monocyte macrophage viability and iNOS, studies were performed with J774.Al macrophages. iNOS mRNA, protein and enzyme activity were induced in J774.Al macrophages by IFN-gamma lipopolysaccharide (LPS). Neither iNOS induction nor inhibition of nitric oxide (NO) formation was associated with significant alterations in the binding, uptake or degradation of native or oxidized LDL. Nontoxic doses of native LDL or of oxidized LDL did not influence iNOS mRNA or protein in macrophages. However, oxidized LDL, but not native LDL or acetyl LDL, inhibited NO production by macrophages in a dose- and time-dependent fashion. Inhibition of iNOS was not correlated with cholesteryl ester formation but with the degree of LDL oxidation. Inhibition of iNOS did not require the scavenger receptor or directed endocytosis and exhibited noncompetitive kinetics. Inhibition of iNOS activity in J774.Al macrophages was produced by lipid from oxidized LDL but not by lipid from native LDL and by PC vesicles containing LPC but not by PC vesicles alone. Inhibition of NO formation diminished apoptosis of the activated macrophages. The data suggest NO production by iNOS and inhibition of the enzyme by oxidized LDL lipid may influence cell viability, cell-cell interactions and vasomotor tone during atherogenesis.
Importance of Soil Fertility, Soil Sampling, and Fertilizer Recommendations in the Inland Pacific Northwest

This study documents the importance of soil fertility in the dryland farming areas of Idaho, Oregon, and Washington. Mail-based surveys conducted in 1981, 1996, and 2011 were used to document the importance placed on soil fertility by farmers. The significant findings of the 2011 survey were (1) more than 62% of the growers attributed more than 50% of their annual crop yield to soil fertility; (2) soil samples were collected at least once in a crop rotation on 91.6% of farms; (3) 31.8% of growers took their own soil samples, whereas fertilizer dealers took 62.8% of the samples; and (4) 54% of growers made their own fertilizer recommendations. Compared to the 1981 survey results, in 2011 farmers were more likely to (1) attribute more of their yields to soil fertility; (2) have their fields soil sampled; (3) collect their own soil samples; and (4) make their own fertilizer recommendations.
Transcriptome analysis of chlamydial growth during IFN-γ-mediated persistence and reactivation

Chlamydia trachomatis is an obligatory intracellular prokaryotic parasite that causes a spectrum of clinically important chronic inflammatory diseases of humans. Persistent infection may play a role in the pathophysiology of chlamydial disease. Here we describe the chlamydial transcriptome in an in vitro model of IFN-γ-mediated persistence and reactivation from persistence. Tryptophan utilization, DNA repair and recombination, phospholipid utilization, protein translation, and general stress genes were up-regulated during persistence. Down-regulated genes included chlamydial late genes and genes involved in proteolysis, peptide transport, and cell division. Persistence was characterized by altered but active biosynthetic processes and continued replication of the chromosome. On removal of IFN-γ, chlamydiae rapidly reentered the normal developmental cycle and reversed transcriptional changes associated with cytokine treatment. The coordinated transcriptional response to IFN-γ implies that a chlamydial response stimulon has evolved to control the transition between acute and persistent growth of the pathogen. In contrast to the paradigm of persistence as a general stress response, our findings suggest that persistence is an alternative life cycle used by chlamydiae to avoid the host immune response.
Robertschochia, a New Name for the Paleocene Mammal Schochia Lucas and Williamson, 1993

IN 1993, Lucas and Williamson coined the name Schochia for a Paleocene mammal (taeniodont) from New Mexico. Michael Oliver has informed me recently that the name Schochia Brunner von Wattenwyl, 1895, is the name of an extant South American grasshopper (Orthoptera: Tettigoniidae). Therefore, in accordance with the International Code of Zoological Nomenclature, to resolve this homonymy, Robertschochia (type species Schochia sullivani Lucas and Williamson, 1993) is here proposed as a replacement name for Schochia. Robertschochia is named for taeniodont expert Robert Schoch.
Theodosius Dobzhansky: A man for all seasons

In 1972, Theodosius Dobzhansky addressed the convention of the National Association of Biology Teachers on the theme “Nothing in biology makes sense except in the light of evolution”. The title of that address (published in The American Biology Teacher, Vol. 35, pp. 125-129) might serve as an epigram of Dobzhansky’s worldview and life, although it is limited in scope, for Dobzhansky believed and propounded that the implications of biological evolution reach much beyond biology into philosophy, sociology, and even socio-political issues. The place of biological evolution in human thought was, according to Dobzhansky, best expressed in a passage that he often quoted from Pierre Teilhard de Chardin: “(Evolution) is a general postulate to which all theories, all hypotheses, all systems must hence forward bow and which they must satisfy in order to be thinkable and true. Evolution is a light which illuminates all facts, a trajectory which all lines of thought must follow – this is what evolution is”.
Phenomenological theory of the rounding of the resistive transition of superconductors

Abstract The effect of fluctuations on conductivity above and near the normal-superconducting transition is calculated by means of the time dependent Ginzburg-Landau equation. The result for films agrees with experiment and microscopic calculation.
Ultrahigh-intensity KrF* laser system.

The operational characteristics of an ultrahigh-intensity subpicosecond large-aperture KrF* laser system are described. Measurements show the achievement of a focal spot diameter of less than 1.7 μm. Combined with measurements of the pulse width and pulse energy, this yields an average intensity of ~2 × 1019 W/cm2, a value corresponding to a peak electric field of ~24 (e/a02). Light sources of this nature will find application in a broad range of studies of the nonlinear properties of matter in the strong-field regime.
Ultraviolet emission from praseodymium doped fibers

Optical spectra of Pr 3+ doped fiber was recorded under dye laser and Ar + laser excitation. Fluorescence was observed from 1 D 2 and 3 P 0 levels. In addition to that emission was also observed at 280 to 300 nm due to cooperative emission.
Using default options within the electronic health record to increase the prescribing of generic-equivalent medications: a quasi-experimental study.

BACKGROUND Low-value services, such as prescribing brand-name medications that have existing generic equivalents, contribute to unnecessary health care spending. OBJECTIVE To evaluate the association of an intervention by using the electronic health record with provider prescription of generic-equivalent medications. DESIGN Quasi-experimental study. SETTING General internal medicine (IM) (n = 2) and family medicine (FM) (n = 2) clinics at the University of Pennsylvania from June 2011 to September 2012. PARTICIPANTS Attending physicians (IM, n = 38; FM, n = 17) and residents (IM, n = 166; FM, n = 34). INTERVENTION In January 2012, the default in the electronic health record was changed for IM providers from displaying brand and generic medications to displaying initially only generics, with the ability to opt out. MEASUREMENTS Monthly prescriptions of brand-name and generic-equivalent β-blockers, statins, and proton-pump inhibitors. RESULTS During the preintervention period, FM providers had slightly higher rates of generic medication prescribing (range, 80.8% to 85.5%) than did IM providers (range, 75.4% to 79.6%), but both groups had similar trends. In the postintervention period relative to the preintervention period, IM providers had an increase in generic prescribing compared with FM providers for all 3 medications combined (5.4 percentage points [95% CI, 2.2 to 8.7 percentage points]; P < 0.001), β-blockers (10.5 percentage points [CI, 5.8 to 15.2 percentage points]; P < 0.001), and statins (4.0 percentage points [CI, 0.4 to 7.6 percentage points]; P = 0.002). Results for proton-pump inhibitors (2.1 percentage points [CI, -3.7 to 8.0 percentage points]; P = 0.47) were not significant. Subset analyses revealed similar findings for attending physicians. Among residents, however, results were imprecise, with wide CIs. LIMITATION Observational single-center evaluation, comparison groups that represented different specialties, and a small subset of medication classes studied. CONCLUSION The use of default options was an effective method to increase the odds of prescribing generic medication equivalents for β-blockers and statins. PRIMARY FUNDING SOURCE U.S. Department of Veterans Affairs and Robert Wood Johnson Foundation.
Effect of Heating Rate on Shortening of Prerigor Chicken Breast Muscle

Abstract Experiments were conducted to evaluate the effects of various heating rates on prerigor chicken breast muscle (Pectoralis major). Heating rates from 2 C per 6 min to 2 C per 18 min (Experiment 1) gave similar results in percentages of myofibrillar, cooking, and total shortening. Myofibrillar shortening began at approximately 39 C and completed at 46 to 50 C, and cooking shortening began at 65 to 66 C, regardless of heating rate. Heat absorbed per gram of muscle sample to onset and completion of myofibrillar shortening, or to onset of cooking shortening, was not different for the various heating rates. A higher muscle temperature at both onset and completion of myofibrillar shortening was observed at the 2 C per 2 min heating rate than at the 2 C per 12 min heating rate (Experiment 2). At 2 C per 2 min, myofibrillar shortening was more extensive, occurred faster, and was coincident to the absorption of more heat per gram of muscle to onset and completion as compared to 2 C per 12 min. The results support the view that rapid heating (≥2 C per 2 min) of prerigor muscle elicits extensive shortening caused by an active contraction.
Phylogenetic distribution of a 24,000 dalton human leukemia-associated antigen on platelets and kidney cells.

The distribution of a 24,000-dalton human leukemia-associated antigen, p24, was examined using the BA-2 and DU-ALL-1 monoclonal antibodies. BA-2 and DU-ALL-1 bound to human, gorilla, orangutan, macaque, and rabbit platelets but did not bind to mouse, rat, guinea pig, dog, horse, sheep, or goat platelets. Orangutan platelets demonstrated a decreased level of binding with BA-2 and DU-ALL-1. In addition, BA-2, but not DU-ALL-1, bound to chimpanzee platelets suggesting that the chimpanzee has lost the epitope of p24 detected by DU-ALL-1. Immunoperoxidase analysis of kidney tissue with BA-2 and DU-ALL-1 revealed staining of distal tubules and glomeruli, which occurred in a similar phylogenetic distribution to that of p24 on platelets. A monoclonal antibody to the high molecular weight common ALL antigen, J-5, reacted with glomeruli and proximal tubules from human, chimpanzee, orangutan, mangaby , rhesus, and rabbit kidneys but failed to react with rat or mouse kidney.
Electron microscopy in end stage renal disease: a case of Fabry's disease.

Fabry's disease is an X-linked error of metabolism with deficiency of the enzyme α-glycosidase A, and glycosphingolipid accumulation in multiple tissues. Patients may be asymptomatic and present with advanced disease. We report a case of a 38 year old white male who presented with end stage renal disease of unknown etiology. He received a living-related donor kidney transplant (mother), but lost the graft after 10 years to multiple episodes of rejection. Review of the native renal biopsy with added ultrastructural studies established the diagnosis of Fabry's disease. Evaluation of renal biopsies showing advanced chronic injury should include electron microscopic studies, which may reveal characteristic diagnostic features, as seen in this case of Fabry's disease. Identification of hereditary disorders involving the kidney is important for appropriate treatment and prevention of disease recurrence. Potential living related donors should be screened for genetic involvement.
Asynchronous Service Analysis of Cloud DVR DataCenter

Currently, the primary legal interpretation approving cloud DVR in cablevision decision relies on individual copies for each video recorded. This means every recorded video in the cloud needs its own copy in the data center. With totally 20 billions of videos available to around 50 millions subscribers, how to manage and store the big data efficiently is required for the datacenter. In this paper, an asynchronous service system with categorizing users by cloud DVR usage is proposed for this purpose. In this system, cloud DVRs with similar requests are constructed in one cluster. The cloud recording service on this cluster becomes idle after a while of no requests. New arriving requests are buffered when the service wakes up. Cloud DVRs accept two requests: cable video recording and Internet video recording. Besides proposing the architecture, we also present the challenges that have to be solved before this strategies could be applied in industries.
Synthesis of β-cyclodextrin conjugated superparamagnetic iron oxide nanoparticles for selective binding and detection of cholesterol crystals

Water-soluble, β-cyclodextrin conjugated superparamagnetic nanoparticles have been constructed. These particles showed selective binding to cholesterol crystals, which opens the door for the detection of cholesterol crystal-related diseases such as atherosclerosis by magnetic resonance imaging (MRI).
α‐Arylation of Esters Catalyzed by the Pd(I) Dimer [P(t‐Bu)3Pd(μ‐Br)]2

Dicyclohexylamine n-Butyllithium Methyl isobutyrate 3-Bromoanisole Di-μ -bromobis(tri-tert-butylphosphine)dipalladium Methyl 2-(3-methoxyphenyl)-2-methylpropanoate Keywords: palladium-catalyzed coupling; α-aryl carboxylic acid derivatives; tri-tert-butylphosphine; palladium (I) dimer; α-arylation of esters; aryl bromides
Identification of Human Genes Related to Olfactory-Specific CYP2G1☆

CYP2G1, which is uniquely expressed in the olfactory mucosa of rats and rabbits, may have functions important for the olfactory chemosensory system. The aim of the present study is to determine whether CYP2G genes are present in the human genome. Several gene fragments were obtained by PCR amplification of human genomic DNA. One fragment, termed E7, which contained an open reading frame for 44 amino acids, is highly homologous in deduced amino acid sequence to residues 322-375 in rabbit or rat CYP2G1. Three other gene fragment, termed E7-8, H2Gp1 and H2Gp2, respectively, were also obtained and found to have structural homology with coding sequences in the rat CYP2G1 gene. RNA-PCR analysis of human nasal RNA indicated that at least one CYP2G gene is transcribed. Southern blot analysis of human genomic DNA with use of cloned E7 or E7-8 as the probe indicated that more than one CYP2G-related gene may be present in the human genome. These results provide a basis for further characterization of the structure and function of the human CYP2G genes.
Immortalized Osteoblast Cell Systems (New Human Fetal Osteoblast Systems)

Scientists are placing increasing emphasis on developing immortalized cells in culture in order to achieve rapidly proliferating, cell systems with extended lifetimes (e.g., increased population doublings) and normal phenotypic characteristics. As shown in Figure 1, cells undergo a differentiation process, function in the differentiated state for a period of time, then undergo an aging process (senescence) and cell death. Cell senescence can be defined as the failure of cells to maintain appropriate functions for life including cell replication, often resulting in programmed cell death (apoptosis) [1, 2]. Cell fusion studies suggest that there are processes in senescent cell nuclei that block DNA replication, maintaining cells in the late G1 stage of the cell cycle, whereas normal cell nuclei stop at the early G1 stage. Current methods to immortalize cells can delay but not prevent senescence (see Fig. 1) [1, 2]. Immortalization appears to be an intermediate step in cell transformation, the latter resulting in loss of many cell properties and a more permanent immortalization.
Energy-efficient power allocation for delay-sensitive traffic over wireless systems

Energy-efficient communication becomes increasingly important for wireless communication systems partially due to the fact that the improvement in battery technology is much slower than the increase for processing power and energy consumption of electronic devices. On the other hand, the telecommunication industry predicts that the mobile data traffic will double almost every year for the next five years with more than two thirds of the future traffic being video. Since many of the video applications are delay-sensitive, it is extremely important to consider energy-efficient design for delay-sensitive traffics over wireless systems. This paper addresses resource allocation for maximizing the energy-efficiency of a wireless link under statistical quality of service (QoS) constraints. In the energy-efficiency analysis, both circuit power and transmission power of a communication system are taken into account. The joint impact of statistical QoS constraints, transmission power, and spectral bandwidth are considered. The unique globally optimal power allocation scheme is characterized. The intuition of the optimal strategy is obtained by looking at both low signal-to-noise ratio (SNR) regime and high SNR regime.
Plasma-assisted oxidation, anodization, and nitridation of silicon

Plasma-assisted oxidation, anodization, and nitridation of silicon have been performed in microwave, rf, and dc plasmas with a variety of reactor configurations and a range of plasma densities. Compared to thermal processes at equivalent substrate temperatures, film growth rates are accelerated by the plasma-enhanced generation of reactive chemical species or by the presence of electric fields to aid charged-particle transport during plasma processes. Oxidation, anodization, and nitridation kinetics, mechanisms, and film properties attainable with plasma enhancement are discussed for crystalline, polycrystalline, and amorphous silicon layers and for silicon-germanium alloys. The use of these plasma methods for surface and interface modification of silicon-based materials and devices is described.
A Comparison of Emission Taxes and Permit Markets for Controlling Correlated Externalities

This paper provides an answer to the question: Are emission taxes an efficient and self-enforcing mechanism to control correlated externality problems? By “correlated externalities” we mean multiple pollutants that are jointly produced by a single source but cause differentiated regional and global externalities. By “self-enforcing” we mean a mechanism that accounts for the endogeneity that exists between competing jurisdictions in the setting of environmental policy within a federation of regions. This mechanism incorporates sequential decision making among the jurisdictions and therefore determines an equilibrium based on the concept of subgame perfection. We find that, unlike joint domestic and international tradable permit markets, joint emission taxes and a hybrid scheme of permits and taxes are neither efficient nor self-enforcing.
The aerobic capacity of tunas: Adaptation for multiple metabolic demands

Abstract Tunas are pelagic, continuous swimmers, with numerous specializations for achieving a high aerobic scope. Tunas must maintain a high rate of energy turnover, and therefore require elevated levels of aerobic performance in multiple physiological functions simultaneously. Based on a model of oxygen demand and delivery to the swimming musculature, the yellowfin's total oxygen consumption at the predicted maximum sustainable (aerobic) swimming velocity is well below estimates of its maximum oxygen consumption. This suggests that the high aerobic scope of tunas may be a specialization that permits continuous swimming in addition to supplying oxygen to other metabolic functions. Estimates of the metabolic costs of oxygen-debt repayment, growth, and specific dynamic action have been combined with this model of aerobic swimming performance to evaluate the total energy budget in relation to the aerobic scope of the yellowfin tuna. Repayment of the oxygen debt incurred during burst swimming is potentially a large component of tuna respiratory metabolism and the relatively high aerobic capacity of tuna white muscle may be a specialization for rapid lactate clearance.
Reduced neuronal size and dendritic length in the medial superior olivary nucleus of albino rabbits.

Abstract We have previously demonstrated that circumscribed structural and functional abnormalities exist in the brainstem auditory system of albino cats. Anomalies in the auditory brainstem evoked response of albino cats were correlated with anatomical defects in the medial superior olivary nucleus (MSO) of the same animals. To examine whether a similar syndrome is present in other albino mammals, we studied the MSO of albino and pigmented rabbits using both Nissl-stained and Golgi-impregnated material. Neurons in the MSO of the albinos were significantly smaller (24%) than those in the pigmented rabbits and there was no overlap in the size distributions between the two groups. Neurons in the abducens nucleus of the albinos were also 14% smaller than in the pigmented rabbits, but this difference was not statistically reliable. The broad overlap in the distributions of neuronal size in the abducens nucleus between groups indicated that not all cells in the albino brainstem are significantly smaller than normal. In the Golgi-impregnated material, the mean total dendritic length for the ‘marginal’ cell type in the MSO was 39% shorter in albinos than in the pigmented animals. The branching density of dendrites was also significantly reduced in the albinos. Mean total dendritic length for cerebellar granule cells was a statistically insignificant 6% longer in the albinos, demonstrating that dendritic structure is not uniformly affected in all regions of the albino brain. The demonstration of similar anatomical differences in albino rabbits and cats indicates that whatever process produces these effects is not species-specific and may be common to the albinos of other mammalian species. The evidence that the amount of cochlear melanin may be related to differences in auditory function further suggests that the differences in the MSO of the albinos may ultimately be related to absence of inner ear pigmentation and not to other gene effects.
Alcohol abuse prevention among Latino adolescents: A strategy for intervention.

In spite of what is known about adolescent alcohol use and the need to prevent alcohol abuse, there is a scarcity of information on alcohol use and alcohol abuse among Latino youth. This paper describes the results of a unique prevention program funded by the National Institute of Alcohol Abuse and Alcoholism in 1978 for Latino youth (12–17 years of age) in East Harlem. Existing literature on Latino youth and alcohol use is reviewed, followed by a description of the program, its setting, and its evaluative methodology. The methodological strategy entailed in-depth interviews with 80 program participants and interviews with staff. The results clearly demonstrate changes in alcohol knowledge, attitudes, and behavior among consistent participants, who constituted about one-third of the 752 participants. The changes were most attributable to the intervention strategies used, namely workshops and cultural materials, as well as outreach to parents and role modeling by staff. The most enlightening results were in terms of reasons for participation and attrition. The final section describes the need for the development of creative educational methods and materials, and difficulties in the use of traditional educational curriculum and evaluation materials with low-income Latino youth.
Structure and function of the conserved 690 hairpin in Escherichia coli 16 S ribosomal RNA. II. NMR solution structure.

The solution structure of the conserved 690 hairpin from Escherichia coli 16 S rRNA was determined by NMR spectroscopy. The 690 loop is located at the surface of the 30 S subunit in the platform region and has been implicated in interactions with P-site bound tRNA, E-site mRNA, S11 binding, IF3 binding, and in RNA-RNA interactions with the 790 loop of 16 S rRNA and domain IV of 23 S rRNA. The structure reveals a novel sheared type G690.U697 base-pair with a single hydrogen bond from the G690 amino to U697-04. G691 and A696 also form a sheared pair and U692 forms a U-turn with an H-bond to the A695 non-bridging phosphate oxygen. The sheared pairs and U-turn result in the continuous single-stranded stacking of five residues from 6693 to U697 with their Watson-Crick functional groups exposed in the minor groove. The overall fold of the 690 hairpin is similar to the anticodon loop of tRNA. The structure provides an explanation for chemical protection patterns in the loop upon interaction with tRNA, the 50 S subunit, and S11. In vivo genetic studies demonstrate the functional importance of the motifs observed in the solution structure of the 690 hairpin.
Unique patterns of comorbidity in posttraumatic stress disorder from different sources of trauma

While there are many studies of comorbidity in combat veterans with posttraumatic stress disorder (PTSD), studies of PTSD from other sources of trauma (e.g., disasters, crimes, and civil violence) are just beginning to emerge. This is the first formal review comparing patterns of comorbidity in PTSD from different sources of trauma. Specific attention is given to the relative frequencies of substance abuse, depression, generalized anxiety, phobic, panic, somatization, psychotic, and personality disorders. The findings reveal that although similarities exist, the comorbidity profiles differ according to the type of trauma experienced and the population studied. Additionally, the evidence suggests that the associated psychiatric disorders are not truly comorbid, but are interwoven with the PTSD.
Lactational Efficiency Complex of Rats: Provisional Model for Interpretation of Energy Balance Data

In experiments to determine maintenance requirements and partial efficiencies of conversion of diet and body tissue to milk, correlations between independent variables interfered with multiple regression procedures usually used in analyzing nutritional energetic data. Therefore, an alternative of a largely deterministic model of energy transformations in lactating rats was developed. Food intake, initial and final body weights, and diet composition were inputs to the model. These inputs were partitioned among the several metabolic functions of lactating rats within the model, and estimates of milk energy, heat increment of production, energy used for maintenance, and heat increment of maintenance were computed. The model was validated with rats and diets not used in model development. Inferences were: (a) average efficiency of body energy conversion to milk is 83%; (b) average gross and net efficiencies of milk production on balanced rations are 57 and 80%; and, (c) maintenance requirements vary as a function of food intake. A logistic function relating maintenance to food intake was developed based on the postulate that changes in intake of food cause changes in weights of several vital organs changing the maintenance requirement. This postulate explains, in part, changes in maintenance requirements during long food restriction and during gestation and lactation.
BIAXIAL TENSION FATIGUE RESPONSE OF CONCRETE

Abstract Concrete structures such as rigid airport pavements are subjected to repeated high-amplitude loads resulting from passing aircraft. The resulting stress-state in concrete is a biaxial combination of compression and tension. It is of interest to understand the response of plain concrete to such loading conditions, which will enable development of realistic material models for implementation in mechanistic pavement design procedures. The objective of this work is to characterize the quasi-static and low-cycle fatigue response of concrete subjected to biaxial stresses in the biaxial tension region, where the principal tensile stress is larger than or equal in magnitude when compared with the principal compressive stress. An experimental investigation of material behavior in the biaxial tension region is conducted. The experimental setup consists of the following test configurations: (a) notched concrete beams tested in three-point bend configuration, and (b) hollow concrete cylinders subjected to torsion. Failure of concrete in the biaxial tension region is shown to be a local phenomenon under quasi-static and fatigue loading, wherein the specimen fails owing to a single crack. The crack propagation is studied using the equivalent elastic crack concept. It is observed that the crack growth rate in constant amplitude fatigue loading exhibits a two-phase process: a deceleration phase followed by an acceleration stage. The crack growth in the acceleration stage is shown to follow Paris law. The model parameters obtained from uniaxial fatigue tests are shown to be sufficient for predicting the considered biaxial fatigue response.
Romantic attraction and happiness.

. Summary.-The hypothesis, suggested by both E. Fromm and T. Reik, that level of unhappiness prior to meeting a love partner should be related to current intensity of love experienced was tested for 61 college dating couples. The results showed that current happiness but nor retrospective report of prior unhappiness was related to romantic love. Fromm (1956) and Reik (1957) suggest that a person's level of unhappiness prior to meeting a love partner should be positively related.. to current intensity of love. Walster (1965) provides indirect support for this hypothesis with respect to liking for a stranger of the opposite sex. The present investigation tests the hypothesis more directly for a sample of naturally occurring dating relationships. Sixty-one dating couples were recruited as paid volunteers from a large midwestern university. Members of each couple were separated and asked to indicate how happy they were at the time just before they started dating their partners. Subjects used a five-point scale with the labels: unhappy, not very happy, fairly happy, happy, and very happy. Then subjects rated their happiness at the present time on the same scale. Subjects then completed Rubin's (1973) dating love scale and Driscoll, et al.'s (1972) measure of general love, along with other personality and demographic measures (see Critelli, 1975). The means and standard deviations for the experimental variables follows, with data for males presented first and for females second for each variable. Previous unhappiness: M = 3.31, SD = .91; M = 3.20, SD = 1.09. Present happiness: M = 4.17, SD = .86; M = 4.44, SD = .70. Here a score of one indicates "unhappy" and a score of five indicates "very happy." Dating love for males M = 36.87, SD = 5.17; for females M = 37.54, SD = 5.93. General love for males M = 16.69, SD = 2.95; for females M = 17.66, SD = 2.40. Most subjects had been dating at least G mo., indicating that these were relatively serious relationships. For females previous happiness correlated .27 (9 < .05) with present happiness, and the two love scales were correlated .70 (p < .001). Previous happiness correlated only -.I6 with each love scale. Current happiness, however, was correlated with dating love .38 (p < .01) and with general love .30
Adaptive local regularization methods for the inverse ECG problem

Abstract One of the fundamental problems in theoretical electrocardiography can be characterized by an inverse problem. We present new methods for achieving better estimates of heart surface potential distributions in terms of torso potentials through an inverse procedure. First, we outline an automatic adaptive refinement algorithm that minimizes the spatial discretization error in the transfer matrix, increasing the accuracy of the inverse solution. Second, we introduce a new local regularization procedure, which works by partitioning the global transfer matrix into sub-matrices, allowing for varying amounts of smoothing. Each submatrix represents a region within the underlying geometric model in which regularization can be specifically `tuned' using an a priori scheme based on the L-curve method. This local regularization method can provide a substantial increase in accuracy compared to global regularization schemes. Within this context of local regularization, we show that a generalized version of the singular value decomposition (GSVD) can further improve the accuracy of ECG inverse solutions compared to standard SVD and Tikhonov approaches. We conclude with specific examples of these techniques using geometric models of the human thorax derived from MRI data.
Not Just Scenery: Viewing Nature Pictures Improves Executive Attention in Older Adults

Background/Study Context: Attention Restoration Theory (Kaplan, 1995, Journal of Environmental Psychology, 15, 169–182) suggests that exposure to nature improves attention. Berman, Jonides, and Kaplan (2008, Psychological Science, 19, 1207–1212) showed that simply viewing nature pictures improves executive attention in young adults. The present study is the first to investigate this Nature Effect in older adults. The authors investigated whether executive attention could be improved in healthy older adults following brief exposure to nature pictures.Methods: Thirty healthy older adults (64–79 years old) and 26 young university students (18–25 years old) participated. They completed the Attention Network Test before and after 6 min of viewing either nature or urban pictures, with random assignment into a picture type. Attention immediately before (most fatigued) and after (most restored) picture viewing was measured, and change in attention was compared between age groups and picture types.Results: Results...
Modeling contention of sparse-matrix-vector multiplication (SMV) in three parallel programming paradigms

We makes use of the LoPC model, which is inspired by both the LogP/PG and BSP models but accounts for contention for message processing resources in parallel programming models to derive a general estimate of execution cost. We carry out this cost estimate analysis for three dominate programming models: message passing, shared memory and distributed shared memory. We analyze a typical application SMV multiplication written in these programming models with irregular receiver-initiated synchronous communication. The LoPC estimate for this application is shown to be reasonably accurate when compared against measured values of runtime of actual empirical computations on an SGI O2000 multiprocessor machine.
#10 Race differences in mammography and colorectal cancer screening among older u.s. women, behavioral risk factor surveillance system (Brfss), 1999

Abstract PURPOSE: National guidelines recommend that persons aged ⩾50 years at average risk for colorectal cancer should have regular screening tests. Breast cancer detection guidelines suggest yearly mammography for all women ⩾40 years of age. This research examines current screening practices for these cancers among US women by age group and by race/ethnicity. METHODS: Data come from the 1999 BRFSS, a state-specific, population-based, random telephone survey of health-related behaviors and preventive practices (n = 58,127 women ⩾ 40; 38,280 ⩾ 50). Data were aggregated across states and weighted prevalence estimates were calculated for receipt of mammography or sigmoidoscopy/colonoscopy. RESULTS: Overall, over 70% of women ⩾40 years had a mammogram within the past two years. There was little variation by race/ethnicity in receipt of recent mammogram, and a curvilinear effect by age group, with the percentage of women having been recently screened dipping under 70% in the youngest (40–44) and oldest (80+) age groups. Conversely, only 42.8% of women ⩾50 years reported having ever received a sigmoidoscopy/colonoscopy. Variation by age group and race/ethnicity was observed among those screened for colorectal cancer. For example, white women (42.8%, 95%CI = 41.9–43.7) were significantly more likely than black (37.6%, CI = 34.7–40.5), Hispanic (33.3%, CI = 37.9–57.6), or Asian (28.2%, CI = 20.0–36.4) women ⩾50 years to have ever had a sigmoidoscopy/colonoscopy. CONCLUSION: Our findings suggest that most women follow the recommended guidelines for mammography screening, however, the majority are not screened for colorectal cancer, which also varies by age and race/ethnicity. Implications of the findings for early detection and cancer prevention will be discussed.