cssi/SciSciGPT-SciSciNet huggingface dataset:
Social Media Use and Depressive Symptoms Among United States Adolescents.

Abstract Purpose Depression is increasingly common among US adolescents; the extent to which social media exposure contributes to this increase remains controversial. Methods We used Monitoring the Future data from 8th and 10th grade students (n = 74,472), 2009–2017, to assess the relationship between daily social media use and depressive symptoms. Self-reported depressive symptom score (range: 4–20) was assessed continuously using a log-transformed outcome and at varying cut scores with logistic regression analyses. First, these outcomes were examined overall, comparing adolescents using social media daily to adolescents who were not. We then estimated predicted depressive symptom scores using 26 predictors in order to establish underlying depression risk. We partitioned students into depression risk quintiles to control for confounding due to underlying depression risk and examine heterogeneity in the association between social media use and depressive symptoms. Sensitivity analyses were used to test the robustness of results with different configurations of the predicted score model, and overall associations were examined in two-year groups to identify differences in effects. Results For girls, in adjusted risk-stratified analysis, daily social media use was not associated with high (vs. low) depressive symptoms. For boys, results were inconsistent, suggesting a protective effect of daily social media use at some cut scores. Results were consistent across sensitivity analyses, and any potential harmful effects appear to be limited to 2009–2010, limiting the evidence supporting social media as a current risk factor for depressive symptoms. Conclusions Among US adolescents, daily social media use is not a strong or consistent risk factor for depressive symptoms.
Sex differences in endocannabinoid modulation of rat CA1 dendritic neurotransmission.

Endocannabinoid sex differences are present in the rat hippocampus. Specifically, at perisomatic GABAergic synapses, tonic anandamide (AEA) and estrogenic-AEA signaling are active in females but not males. Furthermore, in males, hippocampal eCB function varies along the CA1 pyramidal somatodendritic axis. Constitutive CB1 and tonic 2-AG activity are present at perisomatic GABAergic synapses and lacking at dendritic GABAergic synapses. It is unknown if these eCB somatodendritic differences occur at female GABAergic synapses. Moreover, it is unclear whether eCB sex differences occur at hippocampal glutamatergic synapses. In vitro, field potential (fEPSP) recordings were performed to assess eCB sex differences at rat CA3-CA1 dendritic synapses. At female GABAergic synapses, we observed: 1) constitutive CB1 function, 2) tonic AEA, 3) tonic 2-AG and 3) estrogen (ERα)-driven 2-AG activity. In contrast, only constitutive CB1 and tonic 2-AG activity was observed in males. Sex differences in eCB/CB1 signaling at dendritic synapses appear to shift the basal excitatory/inhibitory balance towards excitation in females and towards inhibition in males. Chronic Mild Stress (CMS) exposure (21 days) in female rats reverses CB1constitutive function and impairs both tonic and ERα-driven eCB signaling. Endocannabinoid sex differences under both normal and stress conditions may contribute to sexual disparities in stress-related neurobehavioral disorders.
Assessing the performance of the bootstrap in simulated assemblage networks

Abstract Archaeologists are increasingly interested in networks constructed from site assemblage data, in which weighted network ties reflect sites’ assemblage similarity. Equivalent networks would arise in other scientific fields where actors’ similarity is assessed by comparing distributions of observed counts, so the assemblages studied here can represent other kinds of distributions in other domains. One concern with such work is that sampling variability in the assemblage network and, in turn, sampling variability in measures calculated from the network must be recognized in any comprehensive analysis. In this study, we investigated the use of the bootstrap as a means of estimating sampling variability in measures of assemblage networks. We evaluated the performance of the bootstrap in simulated assemblage networks, using a probability structure based on the actual distribution of sherds of ceramic wares in a region with 25 archaeological sites. Results indicated that the bootstrap was successful in estimating the true sampling variability of eigenvector centrality for the 25 sites. This held both for centrality scores and for centrality ranks, as well as the ratio of first to second eigenvalues of the network (similarity) matrix. Findings encourage the use of the bootstrap as a tool in analyses of network data derived from counts.
Place-Based Redistribution in Simple Location-Choice Models

We study the planning problem of a standard location-choice model to discuss why a planner might optimally redistribute output across locations. In this model, ex-ante identical households value consumption and housing and choose a location in which to live, where locations vary in productivity, amenities, and the quantity of housing. Two features of this model lead the planner to redistribute output. First, the supply of housing is fixed in each location and subject to a congestion externality. Second, households randomly and unobservably vary in their "attachment"' to any given location, affecting both household location choice and utility. We demonstrate that researcher choice in modeling attachment critically affects the size and direction of optimal transfers of output across locations. This is a key problem as the location-choice data do not discipline this facet of the model: A plethora of frameworks may be observationally equivalent, but predicted optimal transfers can vary greatly across approaches. We propose a simple adjustment to the planning problem that removes the influence of the attachment-modeling choice on predicted optimal policy but preserves the planner's incentives to redistribute across locations in response to housing congestion and/or other externalities.
Strategies of improving accuracy in micro-EDM

Abstract Presently, the application of microelectro-discharge machining (micro-EDM) has been extended to various industries including automotive, biomedical, and semiconductor industries. The accuracy and the process repeatability are two important performance parameters to consider in micro-EDM. Some of the sources of inaccuracy during micro-EDM are stochastic nature of process itself, difficulty in handling very small electrodes, vibration of the tool electrode due to flushing jet, challenges in positioning and changing the electrodes, unpredictable tool wear, and so on. In this chapter, the sources of inaccuracy as well as the solutions to improve the accuracy during various forms of micro-EDM process will be discussed in detail. The current research developments as well as future research focus on the areas of accuracy and repeatability during micro-EDM will also be discussed in the chapter.
Alicyclobacillus mali sp. nov., Alicyclobacillus suci sp. nov. and Alicyclobacillus fructus sp. nov., thermoacidophilic sporeforming bacteria isolated from fruit beverages.

Six thermo-acidophilic, spore-forming strains were isolated from a variety of juice products and were characterized genetically and phenotypically. According to 16S rRNA and rpoB gene phylogenetic analyses and average nucleotide identity comparisons against the species demarcation cutoff at <95 %, these six strains were determined to represent three novel species of Alicyclobacillus. The isolates were designated FSL-W10-0018T, FSL-W10-0037, FSL-W10-0048, VF-FSL-W10-0049T, FSL-W10-0057 and FSL-W10-0059T. All six isolates were Gram-positive, motile, rod shaped, contained menaquinone 7 as the major respiratory quinone and had ω-cyclohexane C17 : 0 as a major fatty acid. They were all able to grow aerobically in a range of acidic and moderate thermal conditions. Only isolates FSL-W10-0048 and VF-FSL-W10-0049T were able to produce guaiacol. The following names are proposed for the three new species: Alicyclobacillus mali sp. nov. (type strain FSL-W10-0018T =DSM 112016T=NCIMB 15266T); Alicyclobacillus suci sp. nov (VF-FSL-W10-0049T=DSM 112017T=NCIMB 15265T); and Alicyclobacillus fructus sp. nov. (FSL-W10-0059T=DSM 112018T=NCIMB 15264T).
Introduction to the Old Testament

This volume introduces ancient Israel's Scriptures, or the Hebrew Bible, commonly called the Old Testament. It also traces the legacy of monotheism first found in the pages of the Old Testament. Where pertinent to the message of the Old Testament, the book explores issues of history, comparative religions, and sociology, while striking a balance among these topics by focusing primarily on literary features of the text. In addition, frequent sidebar discussions introduce the reader to contemporary scholarship, especially the results of historical-critical research and archaeology. Along the way, the book explores how the Old Testament conceptualized and gave rise to monotheism, one of the most significant developments in history, giving this study a currency for twenty-first-century readers.
Studies in spectral line formation: III. Non-linear multi-level atom problems

Spectral line formation in nonlinear multilevel atom line transfer problems, considering radiation transfer through plane parallel atmospheres of H and Mg atoms
User-Level Checkpointing for LinuxThreads Programs

Multiple threads running in a single, shared address space is a simple model for writing parallel programs for symmetric multiprocessor (SMP) machines and for overlapping I/O and computation in programs run on either SMP or single processor machines. Often a long running program’s user would like the program to save its state periodically in a checkpoint from which it can recover in case of a failure. This paper introduces the first system to provide checkpointing support for multithreaded programs that use LinuxThreads, the POSIX based threads library for Linux. The checkpointing library is simple to use, automatically takes checkpoint, is flexible, and efficient. Virtually all of the overhead of the checkpointing system comes from saving the checkpoint to disk. The checkpointing library added no measurable overhead to tested application programs when they took no checkpoints. Checkpoint file size is approximately the same size as the checkpointed process’s address space. On the current implementation WATER-SPATIAL from the SPLASH2 benchmark suite saved a 2.8 MB checkpoint in about 0.18 seconds for local disk or about 21.55 seconds for an NFS mounted disk. The overhead of saving state to disk can be minimized through various techniques including varying the checkpoint interval and excluding regions of the address space from checkpoints.
Using training regimens to teach expanding function approximators

In complex real-world environments, traditional (tabular) techniques for solving Reinforcement Learning (RL) do not scale. Function approximation is needed, but unfortunately, existing approaches generally have poor convergence and optimality guarantees. Additionally, for the case of human environments, it is valuable to be able to leverage human input. In this paper we introduce Expanding Value Function Approximation (EVFA), a function approximation algorithm that returns the optimal value function given sufficient rounds. To leverage human input, we introduce a new human-agent interaction scheme, training regimens, which allow humans to interact with and improve agent learning in the setting of a machine learning game. In experiments, we show EVFA compares favorably to standard value approximation approaches. We also show that training regimens enable humans to further improve EVFA performance. In our user study, we find that non-experts are able to provide effective regimens and that they found the game fun.
TIME-DEPENDENT REACTOR PHYSICS IN THE FFTF UNPROTECTED LOSS-OF-FLOW ACCIDENT

Four reactivity models, including the SAS3A reactivity model and the adiabatic reactivity model, are compared for different states in the FFTF unprotected loss-of-flow accident. The SAS3A reactivity for this particular accident is shown to be greater than the adiabatic reactivity and sufficiently different to alter the course of the accident. Separation of the adiabatic reactivity into material and spatial components is shown to permit time-dependent reactivity worth tables which can approximate the adiabatic reactivity for use in the SAS3A point kinetics routine. It is also noted that several reactivity effects are currently ignored in SAS3A.
Effect of receiving diets containing alfalfa and certain feed additives on performance of feeder pigs transported long distances.

Three experiments were conducted to determine the effect of receiving diets containing alfalfa meal and certain feed additives on performance of comingled feeder pigs transported 900 to 1,100 km. In Exp. 1, the inclusion of 9.4% dehydrated alfalfa meal in receiving diets for 2 wk resulted in no difference (P greater than .1) in gain or feed conversion from purchase to market compared with pigs fed a basal corn-soybean meal (CS) diet or a diet containing 20% ground whole oats (O). In Exp. 2, pigs fed receiving diets containing 10% dehydrated alfalfa meal had no improvement (P greater than .1) in gain (.60 vs .61 kg/d) or conversion (3.25 vs 3.17) compared with CS-fed pigs. In Exp. 3, pigs fed a receiving diet for 2 wk containing 10% mid-bloom alfalfa ate more (P less than .002) feed daily for 2 wk (.82 vs .76 kg) and overall (P less than .04; 1.92 vs 1.85 kg) and had an improved (P less than .03) daily gain from purchase to market (.61 vs .59 kg) compared with CS-fed pigs. In Exp. 2, pigs fed diets containing 44 mg/kg tylosin (T) gained similar to pigs fed no additive (O) and slower (P less than .01) than pigs fed 110 mg/kg chlortetracycline (CTC; .59, .60 and .63 kg/d), with no significant differences in feed to gain conversion (3.12, 3.23 and 3.18).(ABSTRACT TRUNCATED AT 250 WORDS)
Protein Kinase C and A3 Adenosine Receptor Activation Inhibit Presynaptic Metabotropic Glutamate Receptor (mGluR) Function and Uncouple mGluRs from GTP-Binding Proteins

One of the most prominent roles of metabotropic glutamate receptors (mGluRs) in the CNS is to serve as presynaptic receptors that inhibit transmission at glutamatergic synapses. Previous reports suggest that the presynaptic effect of group II mGluRs at corticostriatal synapses can be inhibited by activators of protein kinase C (PKC). We now report that activation of PKC inhibits the ability of group II and group III mGluRs to regulate transmission at three major synapses in the hippocampal formation. Thus, this effect may be a widespread phenomenon that occurs at glutamatergic synapses throughout the CNS. We also report that this response is not limited to PKC-activating phorbol esters but that activation of A3 adenosine receptors induces a PKC-dependent inhibition of group III mGluR function at the Schaffer collateral-CA1 synapse. In addition to inhibiting mGluR modulation of excitatory synaptic transmission, we found that activation of PKC reduces inhibition of forskolin-stimulated cAMP accumulation by group II and group III mGluRs, suggesting that the effect of PKC on mGluR signaling is not specific to their effects on neurotransmitter release. This led us to test the hypothesis that PKC acts upstream from effector proteins regulated by mGluRs and acts at the level of the receptor or GTP-binding protein. Interestingly, we found that PKC inhibited mGluR-induced increases in [35S]-GTPgammaS binding in cortical synaptosomes. These data suggest that PKC-induced inhibition of mGluR signaling may be mediated by the inhibition of coupling of mGluRs to GTP-binding proteins.
Human bocavirus: a newly discovered human parvovirus.

Respiratory tract infections are a leading cause of morbidity and mortality worldwide. New respiratory viruses include human metapneumovirus, the coronaviruses severe acute respiratory syndrome-associated coronavirus, NL63, and HKU1, at least one new human rhinovirus, two novel human polyomaviruses, the "giant" mimivirus, and the human bocavirus (HBoV), the subject of this chapter. Characteristics of the viral life cycle inevitably dictate the types of disease parvoviruses are able to induce. In most studies, HBoV is detected in a small («8%) though significant percentage of respiratory specimens. The initial identification of HBoV in respiratory secretions encouraged many investigators to screen for the virus in individuals with respiratory tract disease. In a population-based surveillance study of pneumonia in Thailand, 4.5% of 1,168 individuals with pneumonia tested positive for HBoV. Respiratory specimens in this study were screened for a variety of viral pathogens, in addition to HBoV, and of those in which HBoV was detected, a copathogen was frequently present. HBoV is frequently detected with other respiratory viral pathogens. Detection of HBoV DNA in serum is also a provocative finding. HBoV was detected in serum of children with wheezing. Two closely related genotypes of HBoV were identified in the initial description of HBoV, differing at 26 of the 5,217 base positions in the single-stranded DNA genome. The seroepidemiology of HBoV has been explored using recombinant proteins. Well-designed studies and the development of techniques to propagate and to detect HBoV virions will allow steps forward in investigating the biology of the new parvovirus.
THE TOTAL NEGATION OF A TOPOLOGICAL PROPERTY

The central theme in this paper is the uniform generation of new topological properties from old. Two of the best known properties obtained in this way are total disconnectedness (deriving from connectedness) and scatteredness (deriving from perfectness, i.e. having no isolated points). A third property, lesser known but interesting in its own right, is pseudofiniteness (the cf-spaces studied in [8], [9], [10], [12]) or the class of spaces whose compact subsets are finite. This last-mentioned property derives from compactness in the manner we will explore here. In general, given a class K of topological spaces (K is closed under homeomorphism) we define the class Anti (K) in such a way that "totally disconnected" is co-extensive with "Anti (connected)" and so on. The "anti-property" of most interest to us here is pseudofiniteness which we henceforth relabel "anticompactness". We will also be interested in related anti-properties (Anti (sequentially compact), Anti (LindelSf), etc.) but they will recieve secondary emphasis. The general behavior of the operation Anti (.) itself will occupy some of our attention. However at this stage there are many more questions than answers, so our general treatment will be sketchy, serving mainly to tie together ideas which otherwise may appear to be unrelated. Our set-theoretic conventions are as follows: (i) o denotes the ath infinite initial ordinal, where a is any ordinal. Since we assume the Axiom of Choice throughout, we identify % with the cardinal I. o o0. (ii) An ordinal a is the set of its predecessors. Greek letters near the beginning of the alphabet will usually denote ordinals, while the letters K, A, t will be reserved for cardinals. (iii) The ordinal successor of a is a + 1 a tO {a}, the cardinal successor of K is /. (iv) IfA is any set P(A) denotes the power set of A. (v) B A is the set of all maps f: A --* B. The cardinality of A is written IAI. (vi) If is a cardinal then exp()=12Kl=lP()l, exp(o)is usually denoted by c. (vii) The cartesian product of a family (Ai: i I) of sets is denoted 1-I Ai. If Ai A for all i I then the set A will also at times be denoted 1-I (A). Further notations will be introduced as they arise in the discussion. The referee’s kind suggestions regarding exposition are gratefully acknowledged.
PIC-circuit hybrid model for coupled cavity traveling wave tubes

Summary form only given, as follows. A small/large signal couple-cavity traveling-wave tube (C-CTWT) PIC hybrid model is developed. The code is to determine the interaction between the electron beam and cavity both in the linear and nonlinear regime. A small signal multi-frequency TWT code can provide a description of the power spectrum produced by a low frequency modulated beam. A large signal multi-frequency TWT code is required to study the nonlinear mechanism responsible for mixing the low frequency modulation, for example, from ion noise with the high microwave frequency carrier signal. As the first step, the electron beam is modeled to be one-dimensional electrostatic with the radial behavior modeled using a space charge reduction factor. The electric field within the beam has components from both the space charge and the cavity field. The space charge field is solved by the method used in PDP1. The reduction due to the metallic boundary is also employed. The cavity field is calculated through the cavity equivalent circuit model (R, L, C mutual elements). Each cavity is modeled as a three-port equivalent Curnow circuit. Besides the input and output ports of the circuit, the circuit is coupled to the beam via a gap, the so-called beam port. The voltage across the beam port and the current through it are solved self-consistently.
SQCK: a declarative file system checker

The lowly state of the art for file system checking and repair does not match what is needed to keep important data available for users. Current file system checkers, such as e2fsck, are complex pieces of imperfect code written in low-level languages. We introduce SQCK, a file system checker based on a declarative query language; declarative queries are a natural match for the cross-checking that must be performed across the many structures of a file system image. We show that SQCK is able to perform the same functionality as e2fsck with surprisingly elegant and compact queries. We also show that SQCK can easily perform more useful repairs than e2fsck by combining information available across the file system. Finally, our prototype implementation of SQCK achieves this improved functionality with comparable performance to e2fsck.
The Impact of Transvenous Cardiac Devices on Vascular Access Patency in Hemodialysis Patients

Creating a vascular access in the presence of a cardiovascular implantable electronic device (CIED) in a patient with or approaching end-stage renal disease can be challenging. In this study, we aimed to evaluate the impact of a CIED on the outcomes of vascular access creation in hemodialysis patients and determine their effects on vascular access patency. This is a single-center retrospective review of hemodialysis patients who underwent vascular access creation after CIED placement. Outcomes of vascular access creation and need for endovascular interventions were compared between patients with vascular access created ipsilateral and contralateral to the site of CIED. Comparing patients with arteriovenous (AV) access created ipsilateral to CIED placement (n=19) versus the contralateral side (n=17), the primary failure rate was 78.9% versus 35.3% (p=0.02). For AV accesses that were matured, the median primary patency durations for AV accesses created ipsilateral to the CIED was 11.2 months compared to 7.8 months for AV accesses created contralateral to the CIED (p=1.00). AV accesses created ipsilateral to a CIED have a higher primary failure rate compared with the contralateral arm and should be avoided as much as possible.
Gain-enhanced hyperbolic metamaterials at telecommunication frequencies (Presentation Recording)

Using effective medium theory (EMT), Bloch’s theorem (BT), and the transfer matrix method (TMM), we analyze the possibility of gain-enhanced transmission in metamaterials with hyperbolic dispersion at telecommunication frequencies. We compare different combinations of dissipative metals and active dielectrics, including noble metals, transparent conducting oxides (TCO), III-V compounds, and solid-state dopants. We find that both indium gallium arsenide phosphide (InGaAsP) and erbium-doped silica (Er:SiO2), when combined with silver, show promise as a platform for demonstration of pump-dependent transmission. On the other hand, when these active dielectrics are combined with aluminum-doped zinc oxide (AZO), a low-loss TCO, gain-enhanced transmission is negligible. Results based on EMT are compared to the more accurate BT and TMM. When losses are ignored, quantitative agreement between these analytical techniques is observed near the center of the first Brillouin zone of a one-dimensional periodic structure. Including realistic levels of loss and gain, however, EMT predictions become overly optimistic compared to BT and TMM. We also discuss the limitations to assumptions inherent to EMT, BT, and TMM, and suggest avenues for future analysis.
GRAIN BOUNDARIES IN POLYPHASE CERAMICS

The majority of polyphase ceramics contain a residual glass phase at their grain boundaries. The stability of these phases, particularly at the two-grain boundaries, is of significance since they affect the properties of the material as a whole. Drawing analogies with soap films, the stability of a continuous intergranular phase is considered in terms of the balance between the capillarity and disjoining pressures. The individual components to the disjoining pressures are discussed. It is argued that a large structural component to the disjoining pressure is responsible for the observed constancy of the thickness of its intergranular phase in polyphase silicon nitride ceramics. Mechanisms for the de-wetting of a grain boundary containing an intergranular glass phase are also discussed.
The electrochemical aspects of some biochemical systems—IX. The anomalous behaviour of E. coli with mixed substrates☆

Abstract In a previous study the metabolism of mixed substrates by E. coli harvested in the stationary phase of their growth cycle after being grown in a broth containing glucose was investigated using the “coulokinetic” technique. It was found with the mixtures of glucose and pyruvate, fructose and pyruvate, and glucose and fructose, that glucose, pyruvate, and glucose respectively was consumed more rapidly by the micro-organisms. The present investigation was conducted using E. coli harvested after growth in a fructose medium. With a mixture of glucose and pyruvate the micro-organisms reversed their previously observed behaviour and demonstrated a preference for the utilization of pyruvate. These E. coli showed no pronounced difference in their utilization of the mixture of fructose and pyruvate. The bacteria grown on fructose still utilized glucose more rapidly in the mixture of glucose and fructose. However in this instance both substrates were utilized simultaneously rather than consecutively.
The Maxc Systems

The development odfthis timesharing led to insights on micrporogrammable organization, instruction sets, reliabiilty, and software and firmware development tools.
Arrhythmia Prophylaxis Using Propranolol after Coronary Artery Surgery

Sixty patients undergoing coronary artery bypass grafting operations with cold potassium cardioplegia as the method of myocardial preservation either received low-dose oral propranolol (10 mg every 6 hours; 28 patients) or served as controls (32 patients). The study period began after extubation and ended at the time of hospital discharge. On the fourth postoperative day, 24-hour Holter monitoring was performed to assess additional subtle differences in arrhythmias. The overall incidence of symptomatic postoperative arrhythmias was 31% in the control group: 6 patients (19%) had atrial fibrillation or flutter and 4 patients (12%), ventricular arrhythmias. By contrast, 1 patient (4%) in the propranolol group had atrial fibrillation, and no patient had ventricular arrhythmias. The difference in overall arrhythmia rates between the two groups is significant (p less than 0.025). Twenty-four-hour Holter monitoring demonstrated no additional differences in the frequency of simple or complex atrial or ventricular ectopy between the two groups. We conclude that the incidence of postoperative arrhythmias following coronary artery bypass operation is diminished by the oral administration of prophylactic low-dose propranolol. When compared with our previous study [1], in which the method of myocardial preservation was intermittent aortic cross-clamping and moderate hypothermia, there is no difference in the overall incidence of postoperative arrhythmias.
The relationship between depressive symptoms and nonfatal overdose among a sample of drug users in Baltimore, Maryland

Nonfatal drug overdoses are common among heroin users. While several factors that increase risk of overdose have been identified, there is little research on the role of mental health status. The purpose of this study was to examine the association between depressive symptoms and history of overdose. A sample of 729 opiate and cocaine users completed a cross-sectional survey. Of the sample, 65% reported never having overdosed, 31% had overdosed longer than 12 months before the interview, and 4% had overdosed within the past 12 months. Results indicate that a high score on the Center for Epidemiological Studies Depression Scale (CES-D), a measure of depressive symptoms, was associated with having overdosed within the past 12 months (relative risk ratio [RRR]=3.06; 95% confidence interval [CI], 1.33 to 7.05) after adjusting for age, gender, injection frequency, and physical health impairment. These results suggest that drug users with depressive symptoms should be targeted for overdose prevention programs.
The Texas echelon cross echelle spectrograph

A new mid-IR spectrograph, the Texas Echelon Cross Echelle Spectrograph (TEXES) is under construction. The primary motivation for TEXES is to observe interstellar molecules at very high resolution. TEXES will operate at 7-25 micrometers wavelength with three spectrographic modes: a high resolution cross-dispersed mode, with R approximately equals 100,000, a mid-resolution long-slit mode, with R approximately equals 14,000, and a low resolution long-slit mode, with R approximately equals 2000. In hi-res mode, the primary disperser is a 36 inch long, R10 grating with a 7 mm groove spacing. The echelon is cross-dispersed with a 7 in long R2 echelle. In mid-res mode, the echelon is by-passed with an Offner relay, and the echelle is used by itself. In lo-res mode, a first-order grating is inserted over the echelle. For initial test, TEXES will use a Hughes Aircraft 20 X 64 pixel Si:As impurity-band array, which covers only two echelon orders. It will later be replaced with a 256 X 256 pixel array, which will Nyquist sample approximately 10 orders. The spectrograph has been assembled and tested with a partially complete echelon, demonstrating the soundness of the design. When we began this project, we were unable to find a vendor capable of machining or ruling a diffraction grating with the very coarse ruling required. Consequently, we attempted to hand-fabricate the echelon. We have not succeeded in assembling the echelon with the required precision, missing by about a factor of two. Fortunately, Hyperfine, Inc. is now capable of diamond machining the echelon. We are purchasing a machined echelon, and hope to complete the spectrograph by the end of summer 1998.
Impulse dynamics of coupled synchronous neurons

Synchronization of neurons remains a topic of great interest due in part to practical implications of relevance to desirable as well as to undesirable states. Neural synchrony can be related, for instance, to healthy activity as in the case of the various stages of sleep [1], but can also be related to pathological processes as in the case of Parkinson’s disease [2]. Even though the enormous scientific and technological advances we have been witnessing over the past years helping us understand better the mechanisms behind neurological activities, there is still much to learn, in a context where mathematical models are potentially capable of making important contributions. This presentation comprises two parts. Part 1 describes a set of neuron model equations based on the Huber-Braun (HB) work which was originally intended for studying temperature sensitive neurons [3]. However, the HB equations have been proven to be applicable to a wide range of situations, including studies aimed at clarifying the mechanisms controlling the different neural firing regimes and transitions between them [4] as illustrated in Fig. ​Fig.1,1, as well as neuropsychiatric disorders [5], to name a few. Part 2 details how these neurons can get in synchrony and shows patterns of synchronous behaviors associated with a variety of coupling values and with the firing regimes the neurons were at before being coupled. The argument will be made regarding neuropathologies such as deep depression, for example, in relation of pharmacological treatments capable of altering neuronal firing rates, therefore affecting their synchronization capability. Figure. 1 Conductivity gsrvs. synaptic current Isr color map with the corresponding firing patterns on the right-hand side.
Magnetic and crystallographic structure of Ho6Mn23D22

Abstract Powder neutron diffraction data of Ho 6 Mn 23 D 22 were analyzed by a modified Rietveld technique. At 298 K the space group is Fm3m; at 9 K, P4/mmm. At 298 K the deuteriums occupy the a, f 3 , j and k sites. At 9 K, a noncollinear antiferromagnetic structure is found with Ho moments of ≈ 3.5 μ B /atom on all sites.
Arrayed carbon nanotube infrared properties and potential applications

Carbon nanotubes are found to have versatile properties ranging from exceptional mechanical strength to semiconductor behavior with varying band gap, ranging from 0 eV to ~1 eV. In this work, we have explored the applicability of the carbon nanotubes for optical and IR sensing. Our platform is a vertical integration of highly uniform carbon nanotube arrays with silicon, forming a heterojunction structure. The heterojunction structure exhibits very good current rectification, voltage dependent capacitance and photocurrent response, all suggestive of an electronic diode function. However, we found, that the photogeneration in the first generation test devices is so far dominated by the silicon part of the heterojunction. Of the possible reasons for the elusive mid-IR photocurrent expected in the carbon nanotube is the presence of a thin barrier layer at the heterojunction. Further optimization of the devices is possible by modifying the technology to avoid the barrier layer formation and by improving the quality of the aluminum oxide matrix.
Thermal energy storage technologies and systems for concentrating solar power plants

Abstract This paper presents a review of thermal energy storage system design methodologies and the factors to be considered at different hierarchical levels for concentrating solar power (CSP) plants. Thermal energy storage forms a key component of a power plant for improvement of its dispatchability. Though there have been many reviews of storage media, there are not many that focus on storage system design along with its integration into the power plant. This paper discusses the thermal energy storage system designs presented in the literature along with thermal and exergy efficiency analyses of various thermal energy storage systems integrated into the power plant. Economic aspects of these systems and the relevant publications in literature are also summarized in this effort.
HOW WELL DOES THE CHEMICLAVE STERILIZE HANDPIECES

Using the Food and Drug Administration's protocol for testing health care sterilizers, the author investigated the ability of chemical vapor and steam to sterilize handpieces. Five internal sites of six high-speed handpiece models and four internal positions of one low-speed handpiece model were each inoculated with 10(6) Bacillus stearothermophilus spores. Half-cycle challenges were conducted with Chemiclave models EC 5500 and 8000 (Barnstead/Thermolyne) and with two autoclaves, Tuttnauer 2540M (large chamber) (Tuttnauer USA Co., Ltd.) and Statim Cassette (SciCan USA). Experiments with spores either openly exposed or partially enclosed prove that chemical vapor is an excellent lethal agent, but strongly suggest penetration weakness [corrected].
Interaction of learned relaxation and aversion.

Stimulus controlled elicitation of aversive and relaxation responses was used in a compound stimulus transfer paradigm to examine counterconditioning of autonomic responses. During a single session, experimental and control groups of 18 subjects each received aversive conditioning and relaxation training to criteria. For experimental subjects, both learning experiences involved signal stimuli, whereas control subjects received no contingencies between training and cues. Test trials were presented prior to aversive conditioning and after training was completed. On each test trial subjects received presentations of the aversive cue alone, a compound of the aversive cue with an untrained cue, and a compound of the aversive cue with the relaxation cue. During the preconditioning test trials there were no differences among skin conductance and digital pulse volume responses to the test stimuli. On the test trials after training, responding was significantly reduced to the compound of aversive cue and relaxation cue, as compared to the aversive cue alone or the compound of aversive cue and untrained cue for the experimental group. Control group responses did not differ.
Solid particle erosion resistance of thermally sprayed functionally graded coatings for polymer matrix composites

Abstract Thermally sprayed functionally graded coatings based on a polyimide matrix filled with varying volume fractions of WC–Co have been investigated to improve the erosion and oxidation resistance of polymer matrix composites. A study of the coatings' effectiveness as erosion barriers was accomplished through a statistical analysis of the results of solid particle erosion testing of coated and uncoated polymer matrix composite (PMC) samples using a design of experiments (DoE) approach. Two coating systems and a control sample were evaluated in a randomized test matrix. The coatings were tested at room temperature and 250 °C, using an alumina erodent impacting the coatings at a speed of 100 m/s at angles of 20° and 90°. In general, as the angle of incidence of the eroding material increased from 20° to 90° the volume loss increased. Erosion volume loss at 250 °C was approximately twice that at room temperature.
Operant strain-rate sensitivity during tensile necking

Precisely machined tensile specimens of aluminum-killed steel sheet were used to measure the continuous strain-rate sensitivity,m c, in a series of isothermal tests at different crosshead speeds.m cwas found to be independent of strain and strain rate, in contrast with the “jump” test instantaneous strain sensitivity, mi, which was found to vary strongly with strain rate. A series of matched tensile specimens was also photogridded and deformed at three rates and terminated at four elongations. The strain distributions obtained from these tests were compared with Finite Element Modeling (FEM)—calculated ones based on several strain-rate sensitivity formulations. Comparison of calculations with experiments revealed that the operant rate sensitivity during tensile localization,m t, was intermediate betweenm candm iat each rate and elongation. Once the effective rate sensitivity was established, detailed predictions of strain distributions and failure elongations agreed very well with experiment. A qualitative model of strain-based stress transients was proposed for both strain-rate and strain-state path changes.
STATIONARITY AND CONTROL OF A TANDEM FLUID NETWORK WITH FRACTIONAL BROWNIAN MOTION INPUT

We consider a stochastic control model for a queueing system driven by a two-dimensional fractional Brownian motion with Hurst parameter 0 H H > ½, this model serves to approximate a controlled two-station tandem queueing model with heavy-tailed ON/OFF sources in heavy traffic. We establish the weak convergence results for the distribution of the state process and construct an explicit stationary state process associated with given controls. Based on suitable coupling arguments, we show that each state process couples with its stationary counterpart and we use it to represent the long-run average cost functional in terms of the stationary process. Finally, we establish the existence result of an optimal control, which turns out to be independent of the initial data.
Iron-containing mixed-oxide composites as oxygen carriers for Chemical Looping with Oxygen Uncoupling (CLOU)

Abstract Chemical Looping with Oxygen Uncoupling (CLOU) offers a potentially effective approach for converting solid carbonaceous fuels with inherent carbon dioxide capture. It utilizes oxygen carriers that allow facile and reversible exchange of their lattice oxygen with external environment under varying oxygen partial pressures. The varying and often tunable thermodynamic properties of mixed oxides of first row transition metals make them potentially viable for CLOU applications. In this study, mixed iron–cobalt and iron–manganese oxides are synthesized and evaluated in terms of their ability to uncouple oxygen. The effects of adding a secondary perovskite phase on the uncoupling properties of these primary transition metal oxides are also investigated. The experimental results indicate that different cation compositions exhibit different oxygen uncoupling properties. The initial decomposition temperature of the oxygen carrier sample is found to generally decrease with increasing amount of Co or Mn. Addition of a secondary perovskite phase is found to significantly affect oxygen donation properties of the primary mixed metal oxides. For instance, CLOU properties of mixed Fe–Co oxides are enhanced by perovskite addition. In contrast, oxygen carrying capacity of mixed Fe–Mn oxides under an isothermal condition is negatively affected by perovskite addition. Redistribution of the transition metal cations between the primary and secondary oxide phases is likely to be responsible for such changes in their redox properties.
A new descriptor selection scheme for SVM in unbalanced class problem: a case study using skin sensitisation dataset.

A novel descriptor selection scheme for Support Vector Machine (SVM) classification method has been proposed and its utility demonstrated using a skin sensitisation dataset as an example. A backward elimination procedure, guided by mean accuracy (the average of specificity and sensitivity) of a leave-one-out cross validation, is devised for the SVM. Subsets of descriptors were first selected using a sequential t-test filter or a Random Forest filter, before backward elimination was applied. Different kernels for SVM were compared using this descriptor selection scheme. The Radial Basis Function (RBF) kernel worked best when a sequential t-test filter was adopted. The highest mean accuracy, 84.9%, was obtained using SVM with 23 descriptors. The sensitivity and the specificity were as high as 93.1% and 76.6%, respectively. A linear kernel was found to be optimal when a Random Forest filter was used. The performance using 24 descriptors was comparable with a RBF kernel with a sequential t-test filter. As a c...
Dynorphin-immunoreactive neurons in the rat nucleus accumbens: ultrastructure and synaptic input from terminals containing substance P and/or dynorphin.

The endogenous opioid peptide dynorphin is enriched in neurons in the nucleus accumbens, for which coexistence and synaptic interactions with substance P have been postulated. We examined the immunogold-silver localization of dynorphin and immunoperoxidase labeling for substance P in single coronal sections through the core subregion of the nucleus accumbens of acrolein-fixed rat brain tissue. Dynorphin-immunoreactive somata were more prevalent than substance P-containing neurons throughout the region sampled for ultrastructural analysis. Dynorphin-labeled cells were spherical, contained unindented nuclei, and were closely apposed to other somata and dendrites, some of which also contained dynorphin immunoreactivity. The appositions were characterized by the absence of glial processes and contiguous contacts between the plasma membranes. Smooth endoplasmic reticulum and coated vesicles could also be identified in the cytoplasms on either side of the somatic or dendritic appositions. The dynorphin somata and dendrites received synaptic input from numerous unlabeled as well as dynorphin-and/or substance P-labeled axon terminals. Both types of terminals were morphologically similar in their content of small and large dense core vesicles and their formation of mainly symmetric synaptic specializations. In addition to dynorphin-immunoreactive targets, numerous dynorphin-and substance P-labeled terminals also formed synapses with unlabeled somata and dendrites. In some cases, terminals separately labeled for dynorphin and substance P converged on common targets with or without detectable dynorphin immunoreactivity. Terminals colocalizing both peptides were also found to synapse on unlabeled or dynorphin-labeled somata and dendrites. Additionally, presynaptic interactions were suggested by close appositions between dynorphin-and/or substance P-labeled terminals and other terminals that were unlabeled, dynorphin labeled, or substance P labeled. These results provide morphological data suggesting nonsynaptic communication between dynorphin-immunoreactive neurons and other neurons possibly mediated through receptive sites or second messengers associated with smooth endoplasmic reticulum in the nucleus accumbens. They also indicate that, in this region, 1) the activity of dynorphin neurons may be dependent on activation of autoreceptors for dynorphin as well as substance P and 2) additional neurons lacking dynorphin immunoreactivity are most likely inhibited (symmetric junctions) by terminals containing either one or both peptides. The findings may have implications for motor and analgesic responses to aversive tonic pain transmitted through dynorphin and substance P pathways within the nucleus accumbens. © 1995 Willy-Liss, Inc.
A Comparison of the Model and Full Scale Transom Wave of the R/V Athena

Over the past few years the U.S. Office of Naval Research has sponsored a series of measurements of the transom wave of the R/V Athena and of a 1/8.25-scale model (NSWCCD Model 5365) of the ship. The objectives of the testing were to characterize the free surface wave behind the ship’s transom at both model and full scale for use in identifying hydrodynamic features and for developing and validating numerical simulation tools. The focus of this paper is the comparison of these full scale and model scale measurements, specifically a comparison of the time-averaged free-surface stern wave profiles and the dominant hydrodynamic features, the rooster tail for example. Both the field measurements and the model scale tow tank measurements were made in as calm as possible ambient conditions. Full scale data was collected in the relatively protected waters of St. Andrews Bay, Florida. The winds, which typically build as the day progresses, were minimal, and it was a new moon during the test period, so tidal excursions were also minimized. While measurements were obtained for ship speeds ranging from 3.1 to 6.2 m/s (6 to 12 knots), equivalent to Froude number range based on length (47 m) of 0.14 to 0.29, respectively, the focus of the comparison is for the 0.24 Froude number (10.5 knots full scale) case. Measurements of the full scale stern wave were made by a scanning laser altimeter, while measurements at model scale were made using a traversing set of conductivity finger probes.Copyright © 2010 by ASME