cssi/SciSciGPT-SciSciNet huggingface dataset:
Mitochondrial adaptations to utilize hydrogen sulfide for energy and signaling

Sulfur is a versatile molecule with oxidation states ranging from −2 to +6. From the beginning, sulfur has been inexorably entwined with the evolution of organisms. Reduced sulfur, prevalent in the prebiotic Earth and supplied from interstellar sources, was an integral component of early life as it could provide energy through oxidization, even in a weakly oxidizing environment, and it spontaneously reacted with iron to form iron–sulfur clusters that became the earliest biological catalysts and structural components of cells. The ability to cycle sulfur between reduced and oxidized states may have been key in the great endosymbiotic event that incorporated a sulfide-oxidizing α-protobacteria into a host sulfide-reducing Archea, resulting in the eukaryotic cell. As eukaryotes slowly adapted from a sulfidic and anoxic (euxinic) world to one that was highly oxidizing, numerous mechanisms developed to deal with increasing oxidants; namely, oxygen, and decreasing sulfide. Because there is rarely any reduced sulfur in the present-day environment, sulfur was historically ignored by biologists, except for an occasional report of sulfide toxicity. Twenty-five years ago, it became evident that the organisms in sulfide-rich environments could synthesize ATP from sulfide, 10 years later came the realization that animals might use sulfide as a signaling molecule, and only within the last 4 years did it become apparent that even mammals could derive energy from sulfide generated in the gastrointestinal tract. It has also become evident that, even in the present-day oxic environment, cells can exploit the redox chemistry of sulfide, most notably as a physiological transducer of oxygen availability. This review will examine how the legacy of sulfide metabolism has shaped natural selection and how some of these ancient biochemical pathways are still employed by modern-day eukaryotes.
Mean-field theory of spin-liquid states with finite energy gap and topological orders

The mean-field theory of a T- and P-symmetric spin-liquid state is developed. The quasiparticle excitations in the spin-liquid state are shown to be spin-1/2 neutral fermions (the spinons) and charge e spinless bosons (the holons). The spin-liquid state is shown to be characterized by a nontrivial topological order. Although our discussions are based on the mean-field theory, the concept of the topological order and the associated universal properties (e.g., the quantum number of the quasiparticles) are expected to be valid beyond the mean-field theory. We also discuss the dynamical stability of the mean-field theory.
GRAVITY MODEL APPLICATIONS IN HEALTH PLANNING: ANALYSIS OF AN URBAN HOSPITAL MARKET*

ABSTRACT. In this paper a gravity model is formulated to model a hospital patient flow system. Both spatial and nonspatial measures of separation are used to estimate the model. Travel time was found to provide improved fits over linear distance in modeling patient flow behavior. Transformations of travel time (square root and log) were found to improve model performance further. Model diagnostics suggested additional spatial separation measurw, separation measure parameters demonstrated stability over time. The model is used to forecast the effects of health care financing reform and hospital closure on patient flows in an urban hospital market. Universal health coverage was found to dramatically improve access to hospital services for lower income patient populations. Hospitals at risk for closure were forecast to receive increased patient flows. Medical school hospitals are expected to lose patients after implementation of health reform, with important implications for graduate medical education. Hospital closures were shown to have negative effects on access to services in poor neighborhoods, but relatively little effect on access in the system as a whole.
An automatic gain control circuit with TiO2 memristor variable gain amplifier

An automatic gain control (AGC) topology with a variable gain amplifier utilizing a titanium dioxide (TiO2) memristor is described. A system analysis technique is developed based on the published physical charge-controlled memristor models and unique properties of this passive device. A linearized feedback loop amplitude model is used to design the AGC, and a design tradeoff analysis based on distortion performance is developed. The analysis results are verified with SPICE simulation including a TiO2 memristor SPICE model.
Microcontact Printing of Palladium Colloids: Micron-Scale Patterning by Electroless Deposition of Copper

This paper describes a new method for forming micron- and submicron-scale patterns of copper on surfaces. This method uses microcontact printing (μCP) to deposit colloids that serve as catalysts for the selective electroless deposition of copper. A patterned elastomeric stamp fabricated from poly(dimethylsiloxane) was used to deliver the catalystpalladium colloids stabilized with tetraalkylammonium bromidesto the substrate surface. The electroless deposition of the copper on the sample occurred only where palladium colloid was transferred to the substrate. Electroless deposition catalyzed by the colloids resulted in the formation of metal structures with features having submicron dimensions, with an edge resolution in the range of 100 nm. This technique of activating substrates for electroless metalization was successfully used to pattern glass, (Si/SiO2), and polymers; both flat and curved substrates were used. Microcontact printing of colloids was also used to fabricate metal structures whose thicknesse...
Lectin-biotin assay for slime present in in situ biofilm produced by Staphylococcus epidermidis using transmission electron microscopy (TEM).

A lectin-biotin assay was developed for use in the specific detection of slime produced byStaphylococcus epidermidis RP62A and M187sp11 grown in a chemically defined medium. Mature biofilm was formed on polyvinylchloride (PVC) disks using a combined chemostat-modified Robbins device (MRD) model system. Specimens fixedin situ were: 1) stained with ruthenium red; 2) reacted overnight with biotin-labeled lectins (WGA, succinyl-WGA, Con A, or APA) followed by treatment with gold-labeled extravidin; or 3) reacted with antibodies againstS. epidermidis RP62A capsular polysaccharide/adhesin (PS/A) using an immunogold procedure. WGA and succinyl-WGA (S-WGA), which specifically bindN-acetylglucosamine, were shown by TEM to react only with slime, both cell-associated and exocellular. In contrast, Con A, APA and anti-PS/A reacted with the bacterial cell surface but did not react with slime. These results indicate the usefulness of WGA lectin as a specific marker for detection of the presence and distribution of slime matrix material inS. epidermidis biofilm.
Toward a Critical Theory of Sport

A single, dominant ideology informs both bourgeois and socialist theories of contemporary sport. The gist of this ideology, I argue, is that sport is essentially an instrument of the social order whose central function is to further the economic and political interests of the various nation-states. I restrict my critical attention here to the New Left's perpetuation of this reductionist ideology. My intent in doing so, however, is not to discredit Neo-Marxist sport theory. On the contrary, what I attempt to show is that the New Left's recent advocacy of this ideology vitiates the major tenets of Neo-Marxist thought. My criticism is geared, then, to a resuscitation of the genuine critical thread underlying Neo-Marxist theory. I thus conclude that Neo-Marxist theory, free of ideological distortions, represents one of the most promising critical approaches to understanding the complexities and subtleties of modern sport.
Karl Barth's Christology as a Resource for a Reformed Version of Kenoticism

: This article starts by examining the ‘shift’ in thinking on kenosis from the sixteenth-century doctrine established by Lutheran orthodoxy to the nineteenth-century understanding developed by Gottfried Thomasius. Karl Barth's understanding of ‘kenotic Christology’ was largely controlled by the nineteenth-century definition and, as a result, he rejected it. However, Barth's later treatment of the incarnation in CD IV/I provides resources for taking up the language of kenosis in a positive way that would be thoroughly ‘Reformed’ in character. There are considerable theological gains to be made by such an approach.
Lattice dynamics studies of grain boundary structures. II. Thermodynamic functions

Abstract The change in the atomic vibrational frequency spectrum of an fcc crystal due to the presence of a grain boundary is obtained by lattice dynamics methods. The grain boundary is a 36.9° 〈100〉 symmetric tilt coincidence boundary. An orthorhombic computational cell of 58 atoms containing two such boundaries of opposite rotational sense is employed. The atomic interactions are simulated by a Morse potential developed by Cotterill and Doyama to fit aluminum. From the changes in frequency spectrum the excess thermodynamic functions of the grain boundary are calculated and compared with results from both experiment and the Einstein model. The general shift of frequencies toward lower values is probably due to the weaker binding of many atoms near the boundary, while there are some higher frequency states associated with a few more tightly bound atoms.
High-resolution mapping of D16led-1, Gart, Gas-4, Cbr, Pcp-4, and Erg on distal mouse chromosome 16.

Abstract More than 500 backcross progeny from four intersubspecific backcrosses were typed for six markers on distal mouse chromosome 16. Five of these represented genes that mapped within the Sod-1 to Ets-2 interval, which was shown previously to contain the weaver (wv) gene. The map order, including previously mapped reference markers, is (cen)-D16H21S16-D16Led-1-App-Sod-1-Gart-Gas-4-Cbr-wv-Pcp-4-Erg-Ets-2. This gene order recapitulates the order of the genes on human chromosome 21 where known. Two of these markers further define the region containing the weaver gene to a 3.9-cM segment between Cbr and Pcp-4. In addition, Pcp-4 was localized to human chromosome 21 by the presence of a human-specific restriction fragment in WAV-17, a mouse-human somatic cell hybrid with human chromosome 21 as the only human contribution.
Wi-Fi fingerprinting through active learning using smartphones

Indoor positioning is one of the key components enabling retail-related services such as location-based product recommendations or in-store navigation. In the recent years, active research has shown that indoor positioning systems based on Wi-Fi fingerprints can achieve a high positioning accuracy. However, the main barrier of broad adoption is the labor-intensive process of collecting labeled fingerprints. In this work, we propose an approach for reducing the amount of labeled data instances required for training a Wi-Fi fingerprint model. The reduction of the labeling effort is achieved by leveraging dead reckoning and an active learning-based approach for selecting data instances for labeling. We demonstrate through experiments that we can construct a Wi-Fi fingerprint database with significantly less labels while achieving a high positioning accuracy.
Evidence for the importance of N-dealkylation in opioid pharmacology☆

Abstract The N-dealkylated metabolites of opioids show one of four pharmacologic patterns: (1) morphine-like activity without significant non-morphinelike activity (e.g. noracetylmethadol and di-noracetylmethadol); (2) limited morphine-like activity with conspicuous non-morphine-like activity (e.g. normeperidine); (3) little or no activity, either like or unlike morphine (e.g. normethadone); and (4) definite morphine-likeplus non-morphine-like activities (e.g. normorphine, norlevorphanol, norcodeine, and mono- and di-nor-propoxyphene). Thus, the activity of the normetabolites influences the total pharmacology of these opioids in different ways. Variables which may influence this total opioid pharmacology include: (1) the extent to which opioids are N-demethylated; (2) the relative half-life of the opioid and its normetabolite(s); (3) the extent to which the opioid or its normetabolite(s) exist in the free form; (4) the duration of opioid administration, and (5) the route of opioid administration. Drugs which impair N-demethylation (SKF 525-A and desipramine) influence the pharmacology of methadone, acetylmethadol and meperidine in different, but understandable, ways. Future study of opioid metabolism should incorporate simultaneous measures of the presence of specific metabolites, and measures of pharmacologic activity.
Migration-selection balance at multiple Loci and selection on dominance and recombination.

A steady influx of a single deleterious multilocus genotype will impose genetic load on the resident population and leave multiple descendants carrying various numbers of the foreign alleles. Provided that the foreign types are rare at equilibrium, and all immigrant genes are eventually eliminated by selection, the population structure can be inferred explicitly from the branching process taking place within a single immigrant lineage. Unless the migration and recombination rates were high, this novel method gives a close approximation to the simulation with all possible multilocus genotypes considered. Once the load and the foreign genotypes frequencies are known, it becomes possible to estimate selection acting on the invading modifiers of (i) dominance and (ii) recombination rate on the foreign gene block. We found that the modifiers of the (i) type are able to invade faster than the type (ii) modifier, however, this result only applies in the strong selection/low migration/low recombination scenario. Varying the number of genes in the immigrant genotype can have a non-monotonic effect on the migration load and the modifier’s invasion rate: although blocks carrying more genes can give rise to longer lineages, they also experience stronger selection pressure. The heaviest load is therefore imposed by the genotypes carrying moderate numbers of genes.
Trichuris suis excretory secretory products (ESP) elicit interleukin-6 (IL-6) and IL-10 secretion from intestinal epithelial cells (IPEC-1)

Abstract Immune responses to gastrointestinal helminth infections have received increasing attention due to similarities to allergen-induced responses. In fact, the whipworm parasite of swine, Trichuris suis , has been used in beginning clinical trials as an antidote to inflammatory bowel disease. This strategy was based on this similarity and the recognition that other worms have been documented to induce anti-inflammatory responses in the host. In an effort to understand the basis for this response, we hypothesized that the proteins and peptides secreted by T. suis stimulate local intestinal epithelial cells to produce anti-inflammatory cytokines. To test this hypothesis in a correlate system of the natural swine host, T. suis excretory secretory products (ESP) were used to treat both differentiated and undifferentiated intestinal pig epithelial cells (IPEC-1) in vitro as a model for the effect on villus tip and crypt epithelial cells in the vicinity of the worms. IPEC-1 were exposed to low-level doses (0.3 mg/ml) of T. suis ESP, and IL-4, IL-6 and IL-10 cytokine responses were measured by an enzyme-linked immunosorbant assay (ELISA). IL-6 was the predominant cytokine produced, accompanied by moderate IL-10 secretion from both differentiated and undifferentiated cells. As expected, IL-4 was not produced by IPEC-1. Additionally, IL-6 and IL-10 cytokines were produced within 24 h, suggesting that these two cytokines form part of the primary host response to T. suis infections. These data suggest that T. suis ESP could enhance host immune responses and modulation through the induction of enteric IL-6 and IL-10.
High-Throughput Drug Screen Identifies Chelerythrine as a Selective Inducer of Death in a TSC2-null Setting

Tuberous sclerosis complex (TSC) is an autosomal dominant syndrome associated with tumors of the brain, heart, kidney, and lung. The TSC protein complex inhibits the mammalian or mechanistic target of rapamycin complex 1 (mTORC1). Inhibitors of mTORC1, including rapamycin, induce a cytostatic response in TSC tumors, resulting in temporary disease stabilization and prompt regrowth when treatment is stopped. The lack ofTSC-specificcytotoxictherapiesrepresentsanimportantunmet clinical need. Using a high-throughput chemical screen in TSC2deficient, patient-derived cells, we identified a series of molecules antagonized by rapamycin and therefore selective for cells with mTORC1 hyperactivity. In particular, the cell-permeable alkaloid chelerythrineinducedreactiveoxygenspecies(ROS)anddepleted glutathione (GSH) selectively in TSC2-null cells based on metabolic profiling. N-acetylcysteine or GSH cotreatment protected TSC2-null cells from chelerythrine's effects, indicating that chelerythrine-induced cell death is ROS dependent. Induction of heme-oxygenase-1 (HMOX1/HO-1) with hemin also blocked chelerythrine-induced cell death. In vivo, chelerythrine inhibited the growth of TSC2-null xenograft tumors with no evidence of systemic toxicity with daily treatment over an extended period of time. This study reports the results of a bioactive compound screen and the identification of a potential lead candidate that acts via a novel oxidative stress–dependent mechanism to selectively induce necroptosis in TSC2-deficient tumors. Implications: This study demonstrates that TSC2-deficient tumor cells are hypersensitive to oxidative stress–dependent cell death, and provide critical proof of concept that TSC2deficient cells can be therapeutically targeted without the use of a rapalog to induce a cell death response. Mol Cancer Res; 13(1); 50–62. � 2014 AACR.
Tumour necrosis factor-α single nucleotide polymorphisms are not independent of HLA class I in UK Caucasians with adult onset idiopathic inflammatory myopathies

Objective. To investigate haplotype tagging single nucleotide polymorphisms (SNPs) in the tumour necrosis factor alpha (TNF-alpha) gene, in UK Caucasian idiopathic inflammatory myopathy (IIM) patients. Methods. A cross-sectional, case-control study of four TNF-alpha SNPs was undertaken, comparing cases of polymyositis (PM) (n = 121), dermatomyositis (DM) (n = 109) and myositis overlapping with other connective tissue diseases (CTD-overlap) (n = 73) with normal subjects (n = 177). Subgroup analyses were undertaken after stratifying for myositis specific/associated antibodies. Results. The TNF-308A allele demonstrated a strong association with each myositis disease subgroup vs controls [PM, odds ratio (OR) 2.8, 95% confidence interval 1.9-4.3; DM, OR 2.5, 1.6-3.8; CTD-overlap, OR 3.3, 2.1-5.1]. The TNF-308GA/AA genotype frequency was significantly increased vs controls (PM, OR 3.7, 2.1-6.3; DM, OR 3.2, 1.8-5.5; CTD-overlap, OR 5.0, 2.6-9.6) suggesting a dominant model. The association was strongest in patients possessing anti-aminoacyl transfer RNA synthetase (anti-synthetase) (OR 5.1, 3.3-8.0) or -PM-Scl (OR 5.0, 2.7-8.9) antibodies. The -1031T allele was also a significant risk factor in DM (OR 2.2, 1.4-3.6), anti-synthetase (OR 2.9, 1.6-5.3) and -PM-Scl (OR 5.6, 1.9-6.4) antibody positive patients. The TNF-308A association was lost after adjusting for HLA-B*08, but remained independent of HLA-DQB1*02 (both are alleles forming part of the common ancestral haplotype). The HLA-B*08/TNF-308A/DRB1*03/DQA1*05/DQB1*02 haplotype was a risk factor in all myositis subgroups vs controls (OR 3.0, 1.8-5.3). Conclusions. TNF-308A and -1031T alleles are significant risk factors in the IIMs. In the IIMs, the TNF-308A allele is part of the common ancestral haplotype, but is not independent of HLA-B*08
Management of hot flashes in breast-cancer survivors

Summary Hot flashes can be a major problem for patients with a history of breast cancer. Although oestrogen can alleviate hot flashes to a large extent in most patients, there has been debate about the safety of oestrogen use in survivors of breast cancer. The decrease in hot flashes achieved with progestational agents is similar to that seen with oestrogen therapy but, again, there is some debate about the safety of progestational agents in patients with a history of breast cancer. Several alternative substances have therefore been investigated. These include a belladonna alkaloid preparation, clonidine, soy phyto-oestrogens, vitamin E, gabapentin, and several of the newer anti-depressants, with venlafaxine being the best studied to date. Several studies in progress may provide better non-hormonal means of treating hot flashes in the future.
Energy metabolism defects in Huntington's disease and effects of coenzyme Q10

We investigated whether the Huntington's desease (HD) gene mutation may produce either primary or secondary effects on energy metalbolism. 31P magnetic resonance spectroscopy demonstrated a significant decrease in the phosphocreatine to inorganic phosphate ratio in resting muscle of 8 patients as compared with 8 control subjects. The cerebrospinal fluid lactate-pyruvate ratio was significantly increased in 15 patients as compared with 13 control subjects. Lactate concentrations assessed using 1H magnetic resonance spectroscopy are increased in Huntington's disease cerebral cortex. Treatment with coenzyme Q10, an essential cofactor of the electron transport chain, resulted in significant decreases in cortical lactate concentrations in 18 patients, which reversed following withdrawal of therapy. These findings provide evidence for a generalized energy defect in Huntington's disease, and suggest a possible therapy.
The vitamin D receptor is present in caveolae-enriched plasma membranes and binds 1 alpha,25(OH)2-vitamin D3 in vivo and in vitro

The steroid hormone 1 alpha,25(OH)(2)-vitamin D(3) (1,25D) regulates gene transcription through a nuclear receptor [vitamin D receptor (VDR)] and initiation of rapid cellular responses through a putative plasma membrane-associated receptor (VDR(mem)). This study characterized the VDR(mem) present in a caveolae-enriched membrane fraction (CMF), a site of accumulation of signal transduction agents. Saturable and specific [(3)H]-1,25D binding in vitro was found in CMF of chick, rat, and mouse intestine; mouse lung and kidney; and human NB4 leukemia and rat ROS 17/2.8 osteoblast-like cells; in all cases the 1,25D K(D) binding dissociation constant = 1-3 nM. Our data collectively support the classical VDR being the VDR(mem) in caveolae: 1) VDR antibody immunoreactivity was detected in CMF of all tissues tested; 2) competitive binding of [(3)H]-1,25D by eight analogs of 1,25D was significantly correlated between nuclei and CMF (r(2) = 0.95) but not between vitamin D binding protein (has a different ligand binding specificity) and CMF; 3) confocal immunofluorescence microscopy of ROS 17/2.8 cells showed VDR in close association with the caveolae marker protein, caveolin-1, in the plasma membrane region; 4) in vivo 1,25D pretreatment reduced in vitro [(3)H]-1,25D binding by 30% in chick and rat intestinal CMF demonstrating in vivo occupancy of the CMF receptor by 1,25D; and 5) comparison of [(3)H]-1,25D binding in VDR KO and WT mouse kidney tissue showed 85% reduction in VDR KO CMF and 95% reduction in VDR KO nuclear fraction. This study supports the presence of VDR as the 1,25D-binding protein associated with plasma membrane caveolae.
Analysis of the rate-limiting step of an anaerobic biotrickling filter removing TCE vapors

A detailed analysis of a biotrickling filter treating trichloroethene (TCE) vapors anaerobically is presented and discussed. The biotrickling filter relies on mixed cultures containing bacteria from the genus Dehalococcoides that reductively dechlorinate TCE to ethene. After about 200 days of steady operation, as biomass in the packed bed increased, a partial loss in treatment performance was observed which prompted the present investigations. Analysis of TCE and of its degradation metabolites in the gas phase and in the trickling liquid combined with the calculation of global effectiveness factors revealed that significant mass transfer limitations existed. Depending on the conditions, either the gas film or the liquid film limited the removal of TCE. These findings were confirmed by the determination of gas and liquid films mass transfer coefficients. In all cases, removal of TCE was greater without trickling of liquid. The most plausible reason for the onset of mass transfer limitations was the decrease in the specific interfacial area brought by important biomass growth over time. Overall, this study illustrates how complex kinetic and transport limitations can vary with the operating conditions in biotrickling filters.
BACI debugger: a GUI debugger for the BACI system

Due to the increasing importance of concurrent programming and distributed computing systems, possessing a good understanding of concurrency and its impact on process synchronization is essential. Since concurrency introduces design and execution issues not found in sequential programming, to learn about concurrency issues, it is important that students gain hands on experience actually doing concurrent programming. The best way to get this experience is by using a system developed specifically for teaching concurrent programming. The Ben-Ari Concurrent Interpreter (BACI) is such a system. Unfortunately, when errors are encountered in BACI programs, they are cumbersome to debug. The purpose of this paper is to introduce and describe a Java-based graphical user interface debugger for the BACI language.
Generalization of spatially variant apodization to noninteger Nyquist sampling rates

Spatially variant apodization (SVA) is reformulated for use on synthetic aperture radar imagery with an arbitrary sampling rate. The algorithm is implemented as a spatially varying three-point finite impulse response filter, and constraints on the filter parameters are developed from physically motivated concepts. By varying the parameters of the filter, the sidelobe energy is reduced with no effective loss of resolution. The procedure produces an output comparable to that of the integer Nyquist version of SVA, and effectively eliminates sidelobe artifacts with no loss of mainlobe resolution.
Unified hypothesis for early biochemical sequence of events in steroid hormone action.

Abstract Recent studies using the chick oviduct, a tissue in which progesterone induces synthesis of the protein avidin, have led us to formulate the following sequence of events in progesterone action: steroid permeation of the cell membrane, binding of progesterone to a specific cytoplasmic receptor, transfer of this steroid-receptor complex to the nucleus, binding of the steroid-receptor complex to specific “acceptor sites” on the nuclear chromatin, synthesis of new RNA specific in composition, and synthesis of avidin. These results are discussed in light of evolving experimental information which can now allow us to consider this sequence of events as applicable to the mechanism of action of all steroid hormones.
Abnormal Sweat Electrolytes in a Case of Celiac Disease and a Case of Psychosocial Failure to Thrive Review of Other Reported Causes

Sweat electrolytes were initially elevated in a child who was diagnosed as having celiac disease and also in one with psychosocial failure to thrive. Subsequent sweat tests were normal after nutritional status of the patients had improved with therapy. The reports of elevated sweat electrolytes in conditions other than cystic fibrosis are discussed. It is emphasized that sweat test methods other than the quantitative pilocarpine iontophoresis method are not reliable. The occurrence of false-positive sweat tests demonstrates the need for care in the interpretation of elevated sweat electrolytes and the necessity of performing repeat quantitative pilocarpine iontophoresis for the establishment of the diagnosis of CF. Celiac disease and malnutrition from other causes may cause sweat electrolytes to be elevated.
Effects of species richness and elevated carbon dioxide on biomass accumulation: a synthesis using meta-analysis

Magnitude of growth enhancement by elevated CO2 in a plant assemblage is dependent on a number of biotic and abiotic factors, including species richness. In this meta-analysis, we examined effects of elevated CO2 on plant biomass accumulation in single- (populations) and multi-species (communities) assemblages. The primary objectives were to statistically synthesize the voluminous CO2 studies conducted so far and to assess the collective response of plant growth to elevated CO2 as affected by species richness. Our analysis showed that biomass enhancement by higher CO2 was consistently lower in communities than in populations. For example, total plant biomass (WT) increased only 13% in communities compared to 30% in populations in response to elevated CO2 across all studies included in this synthesis. Above- and below-ground biomass responded similarly as WT to elevated CO2 and species richness. Smaller growth enhancement by CO2 was found in communities consisting of species of different growth forms (woody vs. herbaceous species) or functional groups (legumes vs. non-legumes). This pattern was consistent across three major classes of facilities (closed, semi-open and open systems) used to manipulate CO2 concentrations. An analysis of free-air CO2 enrichment studies revealed that the population–community difference in growth enhancement by higher CO2 was also dependent on the rate of N addition. Populations responded more than communities only when soil was amended with N. From the CO2 studies synthesized in this meta-analysis, it is obvious that the collective growth responsiveness to elevated CO2 will be lower in communities than in populations. We hypothesize that resource usurpation, i.e., competitive compartmentation of growth-limiting resources by less responsive species, may be important in determining growth response to elevated CO2 in a community and is one of the reasons responsible for the lower biomass enhancement by elevated CO2 in communities, as found in this synthesis.
Metabolism in the Caenorhabditis elegans Mit mutants

In many eukaryotes oxidative phosphorylation via the mitochondrial electron transport chain provides the major means of ATP production. Complete removal of this capacity often results in premature death. Recent studies using the nematode Caenorhabditis elegans are surprising because they have revealed that disruption of many of the key components of the normal mitochondrial energy-generating machinery do not result in death, rather they result in adult life span extension. Such mutants have been collectively termed Mit mutants. In this short review, the potential use of alternate metabolic pathways for energy generation by Mit mutants will be considered. The effects of using such pathways on residual mitochondrial functionality, reactive radical species production, and longevity will also be explored.
Caregiver burden and psychological distress in partners of veterans with chronic posttraumatic stress disorder

Caregiver burden and psychological distress were examined in a sample of 71 partners of Vietnam War combat veterans. Partners of patients (n = 51) diagnosed with posttraumatic stress disorder (PTSD) experienced more caregiver burden and had poorer psychological adjustment than did partners of veterans without PTSD (n = 20). Among PTSD caregivers, patient PTSD symptom severity and level of interpersonal violence were associated with increased caregiver burden. When accounting for patient PTSD symptom severity, hostility, presence of major depression, level of interpersonal violence, and health complaints, only PTSD severity was uniquely associated with caregiver burden. Caregiver sociodemographic factors including age, race, education, and the availability of social support, did not moderate the relationship between PTSD symptom severity and caregiver burden. Caregiver burden was strongly related to spouse psychological adjustment.
Regression time warping for similarity measure of sequence

In the paper, we propose regression time warping (RTW), a similarity measure for sequence or time series matching. RTW fuses the linear regression analysis, which controls the shifting and scaling factors between sequences (Lei and Govindaraju, 2004), and the principles of dynamic time warping (DTW), which provides robustness with elastic matching. RTW has complexity as low as O(n), while the complexity of DTW is O(n/sup 2/). Experimental results show the accuracy of RTW in classification is comparable to DTW, and much faster than DTW in term of running time.
Determination of Keratin Protein in a Tape-stripped Skin Sample from Jet Fuel Exposed Skin

Chemical contaminants or their metabolites may bind to and react with keratin proteins in the stratum corneum of the skin. Here, we present a tape-stripping method for the removal and quantification of keratin from the stratum corneum for normalization of extracted concentrations of naphthalene (as a marker for jet fuel exposure) from 12 human volunteers before and after exposure to jet fuel (JP-8). Due to the potential for removal of variable amounts of squamous tissue from each tape-strip sample, keratin was extracted and quantified using a modified Bradford method. Confirmation of the extraction of keratin was verified by western blotting using a monoclonal mouse anti-human cytokeratin antibody. Naphthalene was quantified in the sequential tape strips collected from the skin between 10 and 25 min after a single dose of JP-8 was initially applied. The penetration of jet fuel into the stratum corneum was demonstrated by the fact that the average mass of naphthalene recovered by a tape strip decreased with increased exposure time and subsequent tape strips and that the evaporation of naphthalene was observed to be negligible. There were no significant differences in the amount of keratin or naphthalene removed by tape strips between males and females, between age groups, races or degrees of skin pigmentation. We conclude that (i) the amount of keratin removed with tape strips was not affected by up to a 25 min exposure to JP-8 and (ii) there was a substantial decrease in the amount of keratin removed with consecutive tape strips from the same site, thus, adjusting the amount of naphthalene by the amount of keratin measured in a tape-strip sample should improve the interpretation of the amount of this analyte using this sampling approach. Although we found that normalization of the naphthalene to the amount of keratin in the tape-strip samples did not affect the ability of this method to quantify the dermal exposure to JP-8 under these laboratory conditions, the actual concentration of naphthalene (as a marker for JP-8 exposure) per unit of keratin in a tape-strip sample can be determined using this method and may prove to be required when measuring occupational exposures under field conditions.
Performance analysis of STBC-OFDM transmit diversity with phase noise and imperfect channel estimation

In this paper, we investigate the effects of RF impairments and imperfect channel estimation (ICE) on the performance of quadrature amplitude modulation (QAM) for orthogonal frequency division multiplexing (OFDM) systems employing transmit diversity with two transmit antennas and one receive antenna in a Rayleigh fading environment. We derive the bit error rate (BER) expressions of space-time block codes (STBC)-OFDM system using the Alamouti code. Although the analysis is presented for 16-QAM, it can be easily extended to higher order square QAM constellations. Simulation results are also presented to illustrate the extent of the effects on system performance degradation, with emphasis given to the IEEE 802.16e standard.
Therapeutic Basis of Clinical Pain Modulation

Pain is a hallmark of almost all bodily ailments and can be modulated by agents, including analgesics and anesthetics that suppress pain signals in the central nervous system. Defects in the modulatory systems, including the endogenous pain-inhibitory pathways, are a major factor in the initiation and chronicity of pain. Thus, pain modulation is particularly applicable to the practice of medicine. This review summarizes the existing literature on pain modulation. Here, we critically reviewed the literature from PubMed on pain modulation published primarily within the past 5 years in high impact journals. Specifically, we have discussed important anatomical landmarks of pain modulation and outlined the endogenous networks and underlying mechanisms of clinically relevant pain modulatory methods. The Gate Control Theory is briefly presented with discussion on the capacity of pain modulation to cause both hyper- and hypoalgesia. An emphasis has been given to highlight key areas in pain research that, because of unanswered questions or therapeutic potential, merit additional scientific scrutiny. The information presented in this paper would be helpful in developing novel therapies, metrics, and interventions for improved patient management.
Continuously tuned external cavity semiconductor laser

Continuous tuning (no mode hops) of a grating-tuned external-cavity semiconductor laser by rotation of the grating about a carefully selected point is analyzed and demonstrated using a laser containing a prism beam expander. The analysis predicts the continuous tuning range as a function of pivot-point position and is used to select the point for maximum continuous tuning range. Because dispersive optical elements in the cavity were found to limit the continuous tuning range, the model was modified to include dispersion to first order. The dispersion correction improved the maximum observed tuning range of the 1300-nm-wavelength laser from 600 GHz to nearly 3000 GHz. Details of the cavity and mechanical design as well as pivot-point tolerances are also included. >
Expanding the Use of the Ethical Genogram: Incorporating the Ethical Principles to Help Clarify Counselors’ Ethical Decision-Making Styles

Although it was originally conceived to tap into the intuitive-level of the ethical decision-making process, as outlined by Kitchener, the ethical genogram developed by Peluso (2003) can also illum...
The Mommy Track and Partnership: Temporary Delay or Dead End?

Using unique data from University of Michigan Law School graduates, the authors examine sex differences in promotion to partnership among lawyers. The authors investigate three steps in the partnership process: (1) the decision to attrite early from private practice, (2) the attainment of partnership among those who do not attrite, and (3) determinants of partners’ earnings. Results show that men are less likely than women to leave private practice and more likely than women to become partners, even after controlling for a number of individual characteristics. Among partners, men earn significantly more than women. There is no evidence of a direct marriage or parenthood penalty, but lawyers who have taken time out of the labor force to attend to child care responsibilities are less likely to become partners and earn less if they do become partners. These findings provide strong indirect evidence that women lawyers face multiple glass ceilings in the workplace.
Molecular Approaches to Nerve Regeneration

Current research into regeneration of the nervous system has focused on defining the molecular events that occur during regeneration. One well-characterized system for studying nerve regeneration is the sciatic nerve of rat. Numerous studies have characterized the sequence of events that occur after a crush injury to the sciatic nerve (Cajal 1928; Hall 1989). These events include axon and myelin breakdown, changes in the permeability of the blood vessels, proliferation of Schwann cells, invasion of macrophages, and the phagocytosis of myelin fragments by Schwann cells and macrophages. The distal segment of the injured sciatic nerve provides a supportive environment for the regeneration of the nerve fibres (Cajal 1928; David & Aguayo 1981). Within a period of weeks, the injured sciatic nerve is able to regrow and successfully reinnervate the appropriate targets. Some of the molecules that provide trophic support for the regrowing nerve fibres have been identified, including nerve growth factor (NGF) (Heumann et al. 1987) and glial maturation factor beta (Bosch et al. 1989). Another class of molecules show changes in their rates of synthesis during regeneration, including both proteins (Skene & Shooter 1983; Muller et al. 1986) and mRNA species (Trapp et al. 1988; Meier et al. 1989). To better understand nerve regeneration, we have taken two, parallel molecular approaches to study the events associated with regeneration. The first of these is to study in detail the mechanism of action of a molecule that has been implicated in the regeneration process, nerve growth factor. The second approach is to identify novel gene sequences which are regulated during regeneration. Once the genes are isolated, it will be possible to test for functional roles of the encoded proteins during regeneration. Results from the two approaches are presented in this paper.
Spatial autocorrelation with RUM (Remote Underwater Manipulator): vertical and horizontal structure of a bathyal benthic community☆

Abstract The RUM/ORB unmanned submersible system (Marine Physical Laboratory, Scripps Institution of Oceanography) was used at 1220-m depth to collect precisely located samples separated by distances from 0.1 to 500 m in the San Diego Trough, Southern California continental borderland. Newly developed spatial autocorrelation procedures from the field of quantitative geography were used on this irregularly spaced network of samples to test the statistical significance of the calculated autocorrelations. Scales less than 200 m showed little spatial autocorrelation in total numbers of macrofaunal individuals per sample. Density of Polyophthalamus sp. (Polychaeta, Opheliidae), however, displayed a complex autocorrelative pattern; ‘patches’ of individuals of similar size were observed. Ceratocephale pacifica (Polychaeta, Nereidae), on the other hand, showed negative spatial autocorrelation at the smallest inter-sample distance, perhaps indicative of territoriality. Vertical segregation among confamilial and congeneric species was observed in vertically sectioned subsamples. The majority (82%) of polychaetes, however, appear regularly to inhabit the uppermost centimeter of sediments, suggesting a refinement of current bioturbation models.
Determinants of Bargaining Outcome in Single-family Housing Transactions: An Empirical Examination

Using a hedonic regression model, this paper examines determinants of bargaining outcome in single-family housing transactions. It divides potential factors into three broad categories: dwelling attributes, site amenities, and seller's and buyer's characteristics. Results with use of 1990 data for the Reno-Sparks area in Nevada show that bargaining outcome is determined by seller's asking price, buyer's household income, and some of the dwelling attributes and site amenities. This paper concludes that factors affecting housing price do not necessarily affect bargaining outcome, and first-time home buyers do not statistically bargain less than repeat home buyers.
A new method for computing Moore-Penrose inverse through Gauss-Jordan elimination

Performing elementary row operations on [ A | I ] , we can calculate matrices whose columns form bases for N ( A ) and N ( A � ) easily. These matrices are then used to construct a bordered matrix through which the Moore-Penrose inverse A � of a general matrix A can be obtained through further elementary row operations. Our method is reduced to the classical Gauss-Jordan elimination procedure for the regular inverse when applied to a nonsingular matrix. An example is included to illustrate the new method.
Functional, metal-based crosslinkers for α-helix induction in short peptides.

Many protein–protein interactions that play a central role in cellular processes involve α-helical domains. Consequently, there has been great interest in developing strategies for stabilizing short peptides in α-helical conformations toward the inhibition and interrogation of protein–protein interactions. Here, we show that tridentate hybrid coordination motifs (HCMs), which consist of a natural (histidine, His) and an unnatural (8-hydroxyquinoline, Quin) metal binding functionality, can bind divalent metal ions with high affinity and thereby induce/stabilize an α-helical configuration in short peptide sequences. The Quin functionality is readily introduced onto peptide platforms both during or after solid-state peptide synthesis, demonstrating the preparative versatility of HCMs. A systematic study involving a series of HCM-bearing peptides has revealed the critical importance of the length of the linkage between the Quin moiety and the peptide backbone as well as the metal coordination geometry in determining the extent of α-helix induction. Through ZnII coordination or modification with ReI(Quin)(CO)3, the HCM-bearing peptides can be rendered luminescent in the visible region, thus showing that HCMs can be exploited to simultaneously introduce structure and functionality into short peptides.
Quantitative mass spectrometry of urinary biomarkers

The effectiveness of treatment of renal diseases is limited because the lack of diagnostic, prognostic and therapeutic markers. Despite the more than a decade of intensive investigation of urinary biomarkers, no new clinical biomarkers were approved. This is in part because the early expectations toward proteomics in biomarkers discovery were significantly higher than the capability of technology at the time. However, during the last decade, proteomic technology has made dramatic progress in both the hardware and software methods. In this review we are discussing modern quantitative methods of mass-spectrometry and providing several examples of their applications for discovery and validation of renal disease biomarkers. We are optimistic about future prospects for the development of novel of specific clinical urinary biomarkers.
Rethinking Suicide Surveillance: Google Search Data and Self-Reported Suicidality Differentially Estimate Completed Suicide Risk

Google search data have become an increasingly relied-on source of health information with a dual function as both a facilitative and a preventative resource. We tested the power of Google to predi...
A neural model for straight line detection in the human visual cortex

Building a computational model for how the visual cortex identifies objects is a problem that has attracted much attention over the years. Generally, the interest has been in creating models that are translation, rotation, and luminance invariant. In this paper, we utilize the philosophy of Hough Transform to create a model for detecting straight lines under conditions of discontinuity and noise. A neural network that can learn to perform a Hough Transform-like computation in an unsupervised manner is the main takeaway from this work. Performance of the network when presented with straight lines is compared with that of human subjects. Optical illusions like the Poggendorff illusion could potentially find an explanation in the framework of our model.
A Day by Day Measure of Legislator Ideology: Non-Parametric Smoothing of Legislator Ideal Points with Optimal Classification

This paper presents a method of adapting Poole’s Optimal Classification to smooth ideal points by recovering legislator estimates from localized subsets of the data. Each legislator trend consists of a series of localized kernel estimates, one for each roll call on which the legislator casts a vote. In contrast to the only widely used estimation technique that allows for inter-temporal movement of ideal points, McCarty, Poole, and Rosenthal's DW-NOMINATE, the method presented measures time by the exact date of the roll call rather than by a single integer value for each two-year Congress. The method also does not constrain inter-temporal movement to polynomial functions of time. The result is a set of LOESS-like trends that describe legislator movement through time, thus marking the first roll-call scaling method capable of summarizing legislator movement within and across legislative periods. I illustrate with scalings of the US Senate and the French Fourth Republic.