cssi/SciSciGPT-SciSciNet huggingface dataset:
Defective platelet aggregation in uremia is transiently worsened by hemodialysis

Bleeding is a prominent feature of uremia and remains a significant cause of morbidity in hemodialysis (HD)-dependent patients. To measure the impact of the HD procedure, we performed a prospective cross-over study in eight patients placed consecutively for 2-week periods each on low-flux biocompatible polymethylmethacrylate, low-flux complement-activating cuprophane, and high-flux biocompatible polysulfone membranes. The primary measure of platelet function studied was shear-induced platelet aggregation (SIPA), which has been shown to be a physiologically relevant marker of platelet function and involves the interaction of von Willebrand factor (vWf) with platelet membrane glycoproteins (GP) Ib and IIb-IIIa. Flow-cytometric analysis of the surface expression of platelet membrane GP Ib and GP IIb-IIIa was performed using fluorescein isothiocyanate (FITC)-conjugated monoclonal antibodies CD42b and CD41a, respectively. Multivariate analysis did not demonstrate a statistically significant effect of the type of dialysis membrane on platelet aggregation, calcium flux, or thromboxane B2 production. There was a marked decrease of SIPA in HD patients (pre-HD, mean +/- SEM, 19% +/- 3%) compared with normal controls (43% +/- 3%, P < 0.001), with a further decrease after the HD procedure (post-HD, 12% +/- 2%, P = 0.015 compared with pre-HD). This intradialytic decrease in SIPA correlated with a decrease in GP Ib (pre-HD, 385 +/- 21 mean fluorescence intensity [MFI]; post-HD, 285 +/- 21 MFI, P = 0.0001). GP IIb-IIIa was also significantly decreased post-HD (pre-HD, 1,022 +/- 70 MFI; post-HD, 881 +/- 64 MFI, P = 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)
Using Per gene expression to search for photoperiodic oscillators in the hamster suprachiasmatic nucleus

Abstract The circadian pacemaker in the suprachiasmatic nucleus (SCN) is also believed to underlie photoperiodic (seasonal) timekeeping in mammals. This clock has been modeled as a complex pacemaker composed of two coupled circadian oscillators; variability in their mutual phase relationship could account for the ability to measure daylength, with putative morning and evening oscillators synchronized to dawn and dusk, respectively. Recently, several genes have been identified that are believed to be part of the clock's core oscillatory mechanism. Here, we investigate how such molecular oscillations are altered as a function of photoperiod by analyzing Period (Per1, Per2, and Per3) gene expression at the mRNA level using SCN tissue sections and in situ hybridization. Golden hamsters were entrained to complete 24-h light–dark (LD) cycles with either a long (16 h) or a short (8 h) photophase, or they were entrained to the long complete photoperiod and then allowed to free-run in constant darkness. The results show large photoperiod-dependent changes in the duration of high daytime SCN Per1 and Per2 mRNA levels and small changes in the phase difference between their rhythms.
Synchronous neural afterdischarges in rat hippocampal slices without active chemical synapses

Extracellular field potential and intracellular recordings from neurons in rat hippocampus show that, even with synaptic transmission blocked, antidromic electrical stimuli can trigger afterdischarges of up to 9 seconds duration; during these discharges action potentials of a single neuron were synchronized with extracellularly recorded population spikes. Apparently mechanisms other than recurrent chemical synapses can synchronize and recruit epileptiform events. Measurements of transmembrane potential indicate that transient extracellular electrical fields (ephaptic interactions) contribute to the observed synchrony; electrotonic coupling and changes in the concentration of extracellular ions may also contribute.
The interrelationship between blood pressure, intramuscular pressure, and isometric endurance in fast and slow twitch skeletal muscle in the cat

Two series of experiments were performed to examine the interrelationships between blood pressure, intramuscular pressure, muscle blood flow, and the endurance for isometric exercise in a fast (medial gastrocnemius) and a slow (soleus) twitch muscle of the cat. In the first series of experiments, the relationship between tension and intramuscular pressure was examined. It was found that intramuscular pressure was linearly related to tension in both muscles. However, at any proportion of the muscles maximum tension, the intramuscular pressure of the medial gastrocnemius muscle (the stronger of the muscles) was about twice that of the soleus. A second series of experiments was conducted in which blood pressure was increased above intramuscular pressure and the effect of blood pressure on isometric endurance was measured. The pressure of the perfusing blood of the cat's hind limb was adjusted to either 13.3, 26.6, or 39.9 kPa. It was found that increased perfusion of the muscle resulted in a dramatic increase in the endurance for contractions sustained at isometric tensions below 60% of the muscle's initial strength. In contrast, for contractions above this tension, the effect of increased perfusion was much less pronounced.
Presynaptic input regulates development of β-adrenergic control of rat brain ornithine decarboxylase: Effects of 6-hydroxydopamine or propranolol

Abstract β-Adrenergic control of ornithine decarboxylase (ODC) activity is exerted only during a critical period in central nervous system development, playing an important role in neurotransmitter modulation of cell replication and differentiation. The current study examines the effects of lesions caused by 6-hydroxydopamine administration to neonatal rats, or of gestational exposure to propranolol, on the subsequent development of the ODC response to β-adrenergic stimulation elicited by an acute intracisternal challenge with isoproterenol. 6-Hydroxydopamine treatment severely attenuated the ability of isoproterenol to stimulate ODC in the cerebellum, a tissue that shows a postnatal peak of ODC reactivity. In contrast, much smaller effects were seen in the cerebral cortex, which has an earlier (pre/perinatal) peak of ODC, despite the fact that norepinephrine depletion was more persistent in the cortex. On the other hand, blockade of fetal β-receptors by maternal propranolol infusions resulted in immediate postnatal attenuation of the ODC response in cerebral cortex, but not cerebellum. These data suggest that early exposure of β-receptors to norepinephrine “programs” the subsequent efficiency of the receptor linkage to ODC during a critical ontogenetic period that occurs prenatally in the cerebral cortex and postnatally in the cerebellum.
Inhibition of Bacteriophages of Amino Acid Producing Bacteria by N-Acylamino Acids

The screening of phage inhibitors from various N-acylamino acids in the industrial amino acid fermentation was carried out, using the Brevibacterium lactofermentum No. 2256-L1 phage system. Of the seventy-six chemicals tested, the N-acyl derivative of glutamic acid having 16 or 18 carbon atoms in N-acyl residue showed the selective inhibition for phage infection at the concentration of 20 μg/ml without affecting bacterial growth and fermentation. They were effective also on the other kinds of bacterium-phage systems. With N-palmitoyl-L-glutamic acid, its inhibitory action for phage infection was investigated. The results indicated that the chemical at the concentration of 20 μg/ml did not inhibit the phage adsorption, but diminished the number of infective center at the latent period and suppressed the number of the released phage progenies.
Giant-dipole-resonance absorption and radiative strength function of 196Pt

Abstract The value of the radiative strength function observed in (n, γ) reactions at the neutron binding energy is compatible with the value deduced from the inverse (γ, n) reaction with the help of the hydrodynamical model. An analysis of the observed energy dependence of the radiative strength function suggests that the family of displaced resonance-absorption curves based on the various excited states of 196 Pt have roughly similar shapes in the excitation energy range from 6.3 to 7.9 MeV. More generally, it is made plausible that the value of a certain mean energy should be displaced by an amount precisely equal to the energy displacement of the initial state.
Genetic determinants of on-clopidogrel high platelet reactivity.

Clopidogrel has been used (alone or in association with aspirin) to prevent vascular complications in atherothrombotic patients, to prevent stent thrombosis (ST) in patients undergoing percutaneous coronary intervention (PCI) and as a long-term prevention of cardiovascular and cerebrovascular events. Unfortunately, it is important to note that there are a number of patients who, during clopidogrel therapy, show and maintain a high platelet reactivity (PR), similar to that observed before the start of antiplatelet therapy. Clopidogrel pro-drug is absorbed in the intestine and this process is influenced by P-glycoprotein-1 (P-GP). Its conversion into 2-oxo clopidogrel is regulated by cytochromes (CYP) called CYP2C19, CYP2B6 and CYP1A2. Whereas, the final transformation into the active metabolite is regulated by CYP called CYP2C19, CYP2C9, CYP2B6, CYP3A4, CYP3A5 and, as recently emerged, by the glycoprotein paraoxonase-1 (PON1). The genes encoding these enzymes are characterized by several polymorphisms. Som...
Resonance Raman and infrared spectra of azidoiron(III) and azidomanganese(III) porphyrins

Abstract Infrared and resonance Raman (RR) frequencies of ligand modes have been measured for a series of five-coordinate azidoiron(III) and azidomanganese (III) porphyrins and their 15N3,15N14N2 (Fe, Mn) and 54Fe (Fe) isotopically-substituted analogues. The RR spectra of Fe porphyrins are dominated by the ν(Fe-N3) stretching mode (≈420 cm−1) when excitation is made in resonance with porphyrin π−π* transitions (406.7−514.5 nm). In contrast, the λ(N3) bending (≈630 cm−1) and νas (N3) asymmetric stretching (≈2040 cm−1) modes are the only ligand vibrations which occur in the RR spectra of azido-Mn porphyrins. These two modes are enhanced with visible excitations between a split Soret band, suggesting the presence of a new charge-transfer transition in this region that involves azide π electrons. The polarized nature of these bands (ϱ=0.25) implies that the effective symmetry of the bound N3 ligand is Cs. A band at 349 cm−1 in the IR spectrum of N3Mn(III) TMP (TMP=tetramesitylporphyrin), which shifts to 344 cm−1 upon 15NN2-substitution, is assigned to ν(Mn−N3). This frequency is much lower than ν (Fe−N3), indicating a substantially weaker Mn(III)−N3 bond. A nearly complete set of the azido-bound vibrational frequencies afforded by RR spectra of thin films of N3Fe(III)OEP (OEP=octaethylporphyrin) at 30 K has permitted accurate band assignments based on the observed isotope shifts and the results of normal coordinate analysis carried out on a Fe N N N fragment. This analysis has also shown that the mixed isotope splitting 15N14N2) of the asymmetric intra-azide stretch is due to a non-equivalence in bonding within the azide molecule.
Optical Fourier processing using photoinduced dichroism in a bacteriorhodopsin film

The photoinduced dichroism in bacteriorhodopsin films has been investigated in view of its application for optical Fourier processing. A simple optical system for Fourier processing is demonstrated that does not require precise alignment and vibration isolation. The basic principle of operation relies on the intensity dependence of photoinduced dichroism in a bacteriorhodopsin film. Experimental results with Fourier processing are shown for edge enhancement.
Effects of sodium valproate on corticotropin-releasing factor systems in rat brain.

We hypothesized that divalproex sodium, an anticonvulsant effective in the acute treatment of mania, may act upon neuropeptide systems that utilize corticotropin-releasing factor (CRF). Pharmacokinetic studies demonstrated that valproate has an apparent elimination half life of 17 minutes in rats after acute administration and that there is a nonlinear relationship between chronic dose and serum drug concentration. Acute valproate treatment neither altered plasma adrenocorticotropic hormone (ACTH) or corticosterone concentrations nor produced changes in CRF concentration in any of 10 brain regions examined. Subchronic treatment via SC-implanted osmotic minipumps (875 mg/kg/day × 7 days) resulted in decreased CRF concentrations in the median eminence and raphe nuclei. Moreover, CRF mRNA expression was decreased in the central nucleus of the amygdala (CeA) and paraventricular nucleus (PVN) of the hypothalamus. The benzodiazepine alprazolam, also a positive modulator of GABAergic function, similarly decreases CRF mRNA expression in the CeA. These results suggest that the mood stabilizing effects of valproic acid may be mediated in part by alterations in CRF neuronal activity.
Thin film platinum–palladium thermocouples for gas turbine engine applications

Abstract Thin film platinum:palladium thermocouples were fabricated on alumina and mullite surfaces using radio frequency sputtering and characterized after high temperature exposure to oxidizing environments. The thermoelectric output, hysteresis, and drift of these sensors were measured at temperatures up to 1100 °C. Auger electron spectroscopy was used to follow the extent of oxidation in each thermocouple leg and interdiffusion at the metallurgical junction. Minimal oxidation of the platinum and palladium thermoelements was observed after high temperature exposure, but considerable dewetting and faceting of the films were observed in scanning electron microscopy. An Arrhenius temperature dependence on the drift rate was observed and later attributed to microstructural changes during thermal cycling. The thin film thermocouples, however, did exhibit excellent stability at 1000 °C with drift rates comparable to commercial type-K wire thermocouples. Based on these results, platinum:palladium thin film thermocouples have considerable potential for use in the hot sections of gas turbine engines.
Cross-cultural determinants of occupational affect

The present study is a cross-cultural investigation of the determinants of occupational affect. Data used were from Osgood et al.'s (1975) occupational category in the Atlas of Affective Meaning. Cross-culturally common concepts were rated on functionally equivalent semantic differential scales by high school students in 30 cultures. Using the Tzeng-Osgood (1976) model for validating componential analyses, standardized ratings of 24 occupational concepts on three affective dimensions (Evaluation, Potency, and Activity) were predicted from cross-cultural denotative components. Results indicated that, for almost all cultures, Skill and Morality components were the most important determinants of occupational affect and Sex displayed high variability. Comparisons of data from black and white American samples are also discussed.
Radiation exposure in emergency physicians working in an urban ED: a prospective cohort study

Abstract Objective The National Council on Radiation Protection (NCRP) limits health care–associated occupational exposures to radiation to 5000 mrem/y. Previous studies suggested that emergency physicians were not exposed over this limit. Their relevance to contemporary practice is unknown. We hypothesized that emergency physicians are currently exposed to radiation levels above the NCRP limits. Methods This prospective cohort study was conducted at an urban, academic, level I trauma center emergency department (ED). Thermoluminescent dosimeter radiation badges were placed on the torso and ring finger of all physicians staffing the ED during May 2008. Thermoluminescent dosimeter badges were affixed to 8 portable phones that are carried by physicians in the ED 24 hours a day. At the end of the study period, exposure dose for each subject was estimated. Results Seventy-five physicians enrolled in the study; 41 residents worked a median of 94 hours and 34 attendings worked a median of 54 hours. Compliance for physician badge wearing was 99%, ring wearing was 98%, and phone wearing was 100%. Two subjects had detectable levels of radiation on their torso thermoluminescent dosimeters of 4 and 1 mrem, respectively. One phone badge had a detectable level of 1 mrem. The annual extrapolated exposure for the subject with the highest radiation level would have been 50 mrem, below the 5000 mrem exposure limit for health care workers. Conclusion Emergency physicians working in an urban, academic, level I trauma center ED do not appear to be at risk of exceeding the NCRP dose limits for ionizing radiation exposure to their torso or extremities.
A 108/98 pJ/b 1Gbps Fully Integrated Interference Tolerant Frequency Channelized UWB Transmitter/Receiver

A pulse-based UWB transceiver operating in the 3.25-4.75 GHz band is implemented in 0.18 mum CMOS technology. At 1 Gbps data rate, it dissipates 98mW (98pJ/b) in the receive-mode and 108mW (108pJ/b) in the transmit-mode while achieving a combined Tx/Rx EVM of -32dB. The receiver provides maximum gain of 82dB, 4.5-5.4dB NF, -5 to -10dBm IIP3, and 47dB channel to channel isolation. The transmitter delivers output swing of 800mVpp to 50-ohm load at rates as high as 1.5Gsps.
An investigation of the shrinkage behavior of oriented PVC in a hot air tunnel

The behavior of PVC shrink films in a hot-air tunnel oven was analyzed. The films were found to undergo two modes of shrinkage. Primary shrinkage, which corresponded to macroscopic dimensional changes to conform to the container surface, occurred rapidly once the film was heated above its relaxation temperature. Secondary shrinkage, which corresponded to the elimination of wrinkles and bubbles in the shrunk film, was a much slower process that occurred only when the film was heated above 70°C. The film temperature could be reasonably estimated from a Nusselt analysis of heat transfer between turbulent air and a cylinder.
Stigma and flagellar swelling in relation to light and carotenoids in Euglena gracilis var. bacillaris

Wild-type Euglena gracilis var. bacillaris, W3BUL (a mutant having lower amounts and a different mix of carotenoids), and W10BSmL (in which colored carotenoids are undetectable) were grown in light and darkness and were serially sectioned to ascertain the form and relations of stigma and flagellar swelling by electron microscopy. The length and width of the flagellar swelling in all organisms in light and darkness was the same within experimental error, and this structure showed the characteristic fine reticulate substructure in all cases. The stigma is absent or is reduced to a few tiny vesicles in W10 and show less staining in W3 compared with wild type. In dark-grown resting wild type and W3 the stigma is rather amorphous and only becomes a group of spheres after prolonged exposure to light. Three-dimensional reconstructions of the reservoir region showing the relations of organelles including the stigma and flagellar swelling have been made. Comparing wild-type B and its mutants, the presence of a normal flagellar swelling is not correlated with the ability to form colored carotenoids. This conclusion is supported by experiments with (4-chloro-5-(methylamino)-2-(α,α,α-trifluoro-m-tolyl)-3(2H) pyridazinone) (SAN 9789) a specific inhibitor of carotenoid biosynthesis in Euglena at the phytoene stage. Growing cells of dark-grown wild type or W3 treated with SAN show a very great reduction in the stigma, but the flagellar swelling is unaffected. We conclude that ability to form stigma material does correlate with the ability to make colored carotenoids but light is required to organize this material into the individual spheres characteristic of the normal stigma.
Regional procarbazine delivery reduces testicular toxicity.

Abstract Procarbazine has been implicated as a cause of infertility. Regionalization of drug delivery is a potential method to avoid this problem. We investigated the protective effect of testicular circulatory isolation (TCI) on gonadal toxicity during procarbazine administration in the Sprague-Dawley rat. Four groups ( n = 10/group) were used. Animals in group 1 received no treatment. Rats in groups 2 and 3 were anaesthetized and received TCI of the left testis by clamping of the spermatic cord and gubernaculum immediately before a bolus of intravenous procarbazine (400 mg kg −1 ). The clamping was maintained for 15 min after procarbazine administration in group 2 and for 45 min in group 3. Rats in group 4 received sham surgery immediately before procarbazine administration. On day 70, all rats were killed and necropsied. Testicular toxicity was evaluated qualitatively by histology and quantitatively by measurements of testicular weight, sperm head count, repopulation index, and epididymal index. The results indicated that 15 min of TCI did not mitigate testicular toxicity; 45 min of TCI provided moderate protection against procarbazine-induced testicular toxicity.
Pharmacokinetics of digoxin in the turkey and comparison with other species

Digoxin was administered by bolus intravenous injection to seven broad-breasted white turkey poults at doses of 0.1, 0.15, or 0.2 mg/kg. Plasma digoxin concentrations were measured by a 125 I radioimmunoassay at selected times over the subsequent 24 hr. The data were fitted to a two compartment open pharmacokinetic model. Overall mean values for kinetic variables were: distribution halflife, 38.96 min; elimination halflife, 11.03 hr; volume of distribution in the central compartment, 1.54 liters/kg; total body clearance, 5.81 ml/min/kg. Different doses did not appear to have a significant effect on the identifiable pharmacokinetic variables, suggesting that digoxin disposition is dose independent in the turkey. The results obtained in turkeys were compared with data reported for rats, cats, dogs, and humans. The value for total body clearance of digoxin in the turkey was similar to values found in man, dogs, and cats but considerably less than values reported for rats. The value for elimination halflife in turkeys was somewhat less than values reported for infants and dogs; however, it was considerably different than values reported for rats and cats.
Predicting residue contacts using pragmatic correlated mutations method: reducing the false positives

Predicting residues' contacts using primary amino acid sequence alone is an important task that can guide 3D structure modeling and can verify the quality of the predicted 3D structures. The correlated mutations (CM) method serves as the most promising approach and it has been used to predict amino acids pairs that are distant in the primary sequence but form contacts in the native 3D structure of homologous proteins. Here we report a new implementation of the CM method with an added set of selection rules (filters). The parameters of the algorithm were optimized against fifteen high resolution crystal structures with optimization criterion that maximized the confidentiality of the predictions. The optimization resulted in a true positive ratio (TPR) of 0.08 for the CM without filters and a TPR of 0.14 for the CM with filters. The protocol was further benchmarked against 65 high resolution structures that were not included in the optimization test. The benchmarking resulted in a TPR of 0.07 for the CM without filters and to a TPR of 0.09 for the CM with filters. Thus, the inclusion of selection rules resulted to an overall improvement of 30%. In addition, the pair-wise comparison of TPR for each protein without and with filters resulted in an average improvement of 1.7. The methodology was implemented into a web server http://www.ces.clemson.edu/compbio/recon that is freely available to the public. The purpose of this implementation is to provide the 3D structure predictors with a tool that can help with ranking alternative models by satisfying the largest number of predicted contacts, as well as it can provide a confidence score for contacts in cases where structure is known.
Multiplexed DNA quantification by spectroscopic shift of two microsphere cavities.

We have developed a novel, spectroscopic technique for high-sensitivity, label-free DNA quantification. We demonstrate that an optical resonance (whispering gallery mode) excited in a micron-sized silica sphere can be used to detect and measure nucleic acids. The surface of the silica sphere is chemically modified with oligonucleotides. We show that hybridization to the target DNA leads to a red shift of the optical resonance wavelength. The sensitivity of this resonant technique is measured as 6 pg/mm 2 mass loading, higher as compared to most optical single-pass devices such as surface plasmon resonance biosensors. Furthermore, we show that each microsphere can be identified by its unique resonance wavelength. Specific, multiplexed DNA detection is demonstrated by using two microspheres. The multiplexed signal from two microspheres allows us to discriminate a single nucleotide mismatch in an 11-mer oligonucleotide with a high signal-to-noise ratio of 54. This all-photonic whispering gallery mode biosensor can be integrated on a semiconductor chip that makes it an easy to manufacture, analytic component for a portable, robust lab-on-a-chip device.
Predicting responses to sunitinib using single nucleotide polymorphisms: Progress and recommendations for future trials

Targeted therapy with tyrosine kinase inhibitors has led to a substantial improvement in the standard of care for patients with advanced or metastatic clear cell renal cell carcinoma. Because the mechanism of action, metabolism and transport of tyrosine kinase inhibitors can affect outcome and toxicity, several investigators have pursued the identification of single nucleotide polymorphisms (SNPs) in genes associated with these actions. We discuss SNPs associated with outcome and toxicity following sunitinib therapy and provide recommendations for future trials to facilitate the use of SNPs in personalized therapy for this disease.
Genes@Work: an efficient algorithm for pattern discovery and multivariate feature selection in gene expression data

Motivation: Despite the growing literature devoted to finding differentially expressed genes in assays probing different tissues types, little attention has been paid to the combinatorial nature of feature selection inherent to large, high-dimensional gene expression datasets. New flexible data analysis approaches capable of searching relevant subgroups of genes and experiments are needed to understand multivariate associations of gene expression patterns with observed phenotypes. Results: We present in detail a deterministic algorithm to discover patterns of multivariate gene associations in gene expression data. The patterns discovered are differential with respect to a control dataset. The algorithm is exhaustive and efficient, reporting all existent patterns that fit a given input parameter set while avoiding enumeration of the entire pattern space. The value of the pattern discovery approach is demonstrated by finding a set of genes that differentiate between two types of lymphoma. Moreover, these genes are found to behave consistently in an independent dataset produced in a different laboratory using different arrays, thus validating the genes selected using our algorithm. We show that the genes deemed significant in terms of their multivariate statistics will be missed using other methods. Availability: Our set of pattern discovery algorithms including a user interface is distributed as a package called Genes@Work. This package is freely available to non-commercial users and can be downloaded from our website (http://www.research.ibm.com/FunGen).
Diagnosis of reversible causes of coma

Summary Because coma has many causes, physicians must develop a structured, algorithmic approach to diagnose and treat reversible causes rapidly. The three main mechanisms of coma are structural brain lesions, diffuse neuronal dysfunction, and, rarely, psychiatric causes. The first priority is to stabilise the patient by treatment of life-threatening conditions, then to use the history, physical examination, and laboratory findings to identify structural causes and diagnose treatable disorders. Some patients have a clear diagnosis. In those who do not, the first decision is whether brain imaging is needed. Imaging should be done in post-traumatic coma or when structural brain lesions are probable or possible causes. Patients who do not undergo imaging should be reassessed regularly. If CT is non-diagnostic, a checklist should be used use to indicate whether advanced imaging is needed or evidence is present of a treatable poisoning or infection, seizures including non-convulsive status epilepticus, endocrinopathy, or thiamine deficiency.
Terminal pair reliability of tree-type computer communication networks

An analysis is presented for computing the terminal pair reliabilities of the two-centered tree (2CT), the X-tree (XT), and the ring-tree (RT). A building block is identified in the 2CT, from which a decomposition algorithm is formulated. Another building block is identified for the XT and RT from which a truss-transformation method and a computational algorithm are obtained. By comparison, it is shown that an XT is a good candidate for applications such as high bandwidth networks with high link reliability. >
Changes in Producers’ Perceptions of Within-Field Yield Variability after Adoption of Cotton Yield Monitors

This article investigates how information from cotton yield monitors influences the perceptions of within-field yield variability of cotton producers. Using yield distribution modeling techniques and survey data from cotton producers in 11 southeastern states, we find that cotton farmers who responded to the survey tend to underestimate within-field yield variability (by approximately 5-18%) when not using site-specific yield monitor information. Results further indicate that surveyed cotton farmers who responded to a specific question about yield monitors place a value of approximately $20/acre/year (on average) on the additional information about within-field yield variability that the yield monitor technology provides.
Antenatal Diagnosis of Subependymal Heterotopia

Subependymal heterotopia consist of gray matter nodules along the lateral ventricular walls and are associated with epilepsy and other cerebral malformations. Some cases have an X-linked inheritance, and early antenatal diagnosis of affected fetuses is important for appropriate management. We present a case of heterotopia diagnosed by sonography and MR imaging at 23 weeks' gestation and discuss the differential diagnosis, reviewing the evolution and imaging appearances of the germinal matrix and its implications for detection of heterotopia.
Identifying collective modes through impurity pinning in cuprate superconductors

We propose a scanning tunneling spectroscopy experiment to identify the nature and relative strength of collective modes in the high-temperature superconductors HTSCs. To this end, we show that the pinning of diverse collective modes by impurities leads to qualitatively different fingerprints in the local density of states. These fingerprints directly reflect the modes’ magnetic or nonmagnetic character, as well as their wave vectors and correlation lengths. These results provide an alternative method for identifying collective modes not only in the HTSCs but also in other correlated electron systems.
Overall Effectiveness and Flowfield Measurements for an Endwall With Nonaxisymmetric Contouring

Endwall contouring is a technique used to reduce the strength and development of three-dimensional secondary flows in a turbine vane or blade passage in a gas turbine. The secondary flows locally affect the external heat transfer, particularly on the endwall surface. The combination of external and internal convective heat transfer along with solid conduction determines component temperatures, which affect the service life of turbine components. A conjugate heat transfer model is used to measure the non-dimensional external surface temperature, known as overall effectiveness, of an endwall with non-axisymmetric contouring. The endwall cooling methods include internal impingement cooling and external film cooling. Measured values of overall effectiveness show that endwall contouring reduces the impingement effectiveness alone, but increases the effectiveness of film cooling alone. Given the combined case of both impingement and film cooling, the laterally averaged overall effectiveness is not significantly changed between the flat and contoured endwall. Flowfield measurements indicate that the size and location of the passage vortex changes as film cooling is added and as the blowing ratio increases. Because endwall contouring can produce local effects on internal cooling and film cooling performance, the implications for heat transfer should be considered in endwall contour designs.© 2015 ASME
Biopsy specimen acquisition in patients with newly diagnosed peptic ulcer disease as determined from a national endoscopic database.

Abstract Background Eradication of Helicobacter pylori infection decreases peptic ulcer recurrence. Therefore, assessment of Helicobacter pylori status is recommended for patients with newly diagnosed peptic ulcer disease. Methods Data obtained from the Clinical Outcomes Research Initiative's national endoscopic database were analyzed to characterize the acquisition of biopsy specimens in patients with a non-bleeding gastric or duodenal ulcer newly diagnosed by EGD. Results Between January 2000 and June 2003, 8299 patients underwent EGD with identification of non-bleeding peptic ulcer disease in the stomach (5390) or the duodenum (2909). Overall, biopsy specimens were obtained from the gastric or duodenal ulcer in 5578 (67%) of these patients. Multivariate analysis identified male gender (odds ratio [OR] 0.75, 95% confidence interval (CI) [0.66-0.85] vs. female), age greater than 75 years (OR 0.67, 95% CI [0.57-0.77] vs. age p Conclusions The findings of this study suggest that there is variation in the rates of biopsy specimen acquisition among patients with ulcers who may be at risk for Helicobacter pylori infection. Given the established benefit of Helicobacter pylori eradication, further study is needed to determine whether physicians are diagnosing and treating Helicobacter pylori infection adequately in patients with peptic ulcer.
Pricing differentiated Internet services

One of the critical challenges facing the networking industry today is to increase the profitability of Internet services. One well-known method in economics for increasing the revenues of a service is to segment its market through differentiation. However, special characteristics of Internet services, such as congestion externality, may complicate the design and provisioning of such offerings. In this paper, we study how a provider should price its services differentially based on their characteristics. By using a game-theoretic approach, we show that even with a simple two-class differentiated service model, if prices are not properly matched with service qualities, then the system may settle into an undesirable equilibrium similar to that in the classical "prisoner's dilemma" game. In addition, there may not even be a stable equilibrium under certain conditions. We then show that dynamic pricing approaches, in which prices are chosen according to users' relative preferences over different service classes, may be used to avoid such types of problems.
Sorting of the Alzheimer's disease amyloid precursor protein mediated by the AP-4 complex.

Adaptor protein 4 (AP-4) is the most recently discovered and least well-characterized member of the family of heterotetrameric adaptor protein (AP) complexes that mediate sorting of transmembrane cargo in post-Golgi compartments. Herein, we report the interaction of an YKFFE sequence from the cytosolic tail of the Alzheimer's disease amyloid precursor protein (APP) with the μ4 subunit of AP-4. Biochemical and X-ray crystallographic analyses reveal that the properties of the APP sequence and the location of the binding site on μ4 are distinct from those of other signal-adaptor interactions. Disruption of the APP-AP-4 interaction decreases localization of APP to endosomes and enhances γ-secretase-catalyzed cleavage of APP to the pathogenic amyloid-β peptide. These findings demonstrate that APP and AP-4 engage in a distinct type of signal-adaptor interaction that mediates transport of APP from the trans-Golgi network (TGN) to endosomes, thereby reducing amyloidogenic processing of the protein.
Trends in abundance and current status of harbor seals in oregon : 1977-2003

The distribution and abundance of harbor seals (Phoca vitulina richardii) in Oregon were monitored from 1977 to 2003 by aerial photographic surveys. Harbor seals on shore were counted each year during the reproductive period. Mean annual counts of non-pups (adults and subadults) were used as an index of population size and the trend in the counts was modeled using exponential (density-independent) and generalized logistic (density-dependent) growth models. Models were fit using maximum likelihood and evaluated using Akaike's Information Criterion. The population dynamics of harbor seals in Oregon were best described by the generalized logistic model. The population grew following protection under the Marine Mammal Protection Act of 1972 until stabilizing in the early 1990s. The estimated absolute abundance of harbor seals (all age classes) during the 2002 reproductive period was 10,087 individuals (95% confidence interval was 8,445-12,046 individuals). The current predicted population size for harbor seals in Oregon is above its estimated maximum net productivity level and hence within its optimum sustainable population range. We speculate that recent increases in ocean productivity in the eastern Pacific Ocean may lead to an increase in carrying capacity and renewed growth in Oregon's harbor seal population.
The Benefits of Reciprocated Friendships for Treatment-seeking Obese Youth

Objective The current study examined the attributes of the reciprocated friends (RF) of a group of clinically referred obese children and the impact of these friendships on emotional well-being. Methods Classroom visits for 87 obese youth [body mass index (BMI) >95th percentile; 8- to 16-years old) were completed to obtain peer reports of social functioning, including reciprocated friendships, and to identify a demographically similar non-overweight comparison peer (CPO, n ¼ 76). Subsequently, data regarding self-reported emotional well-being were collected from 84 obese children and 74 CPOs. Results Most obese children (68%) had at least one RF in their classroom. RFs were similar socially to CPOs and functioned more adaptively in the peer environment relative to obese children. Among obese youth, having at least one reciprocated friendship moderated the effect of sensitive-isolated behavior on loneliness. Conclusion Friendships may be a source of support for better psychosocial outcomes for obese youth.
Beyond PCBM: Understanding the Photovoltaic Performance of Blends of Indene‐C60 Multiadducts with Poly(3‐hexylthiophene)

The effect of functionalization of the C60 cage with multiple indene groups in relation to the dynamics of photogenerated species in blends with poly(3-hexylthiophene) (P3HT) and the performance of P3HT:indene-C60 photovoltaic devices is reported. Despite the systematic decrease of the electron affinity of the acceptor with the number of additions, exciton dissociation is efficient in blends of P3HT with all three indene-C60 derivatives. By replacing the prototypical acceptor [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) with mono-indene-C60 (ICMA) or a sample of a mixture of bis-indene-C60 regioisomers (ICBA) the power conversion efficiency is enhanced, predominantly due to an increase in the open-circuit voltage that originates from the lower electron affinity of the indene-C60 acceptor. The use of an acceptor sample that represents a mixture of tris-indene-C60 (ICTA) regioisomers results in a reduction of the short-circuit current density, fill factor, and open-circuit voltage of the photovoltaic device. The electron mobility in ICTA domains is ca. a factor 10 lower than in ICMA and ICBA. Density functional theory calculations of the LUMO energies in ICTA isomers demonstrate that energetic disorder caused by the presence of regioisomers is unlikely to be responsible for the low electron mobility in ICTA. The observed deterioration in device performance is attributed to the formation of small ICTA clusters “coated” in insulating indene units that reduce electronic coupling between the molecules and cause the low electron mobility in ICTA domains. These findings indicate that while multiple additions to a fullerene cage provide a facile methodology for controlling the energy levels, they may have limited success in improving OPV device performance.
Mapping the MRI voxel volume in which thermal noise matches physiological noise--implications for fMRI.

This work addresses the choice of the imaging voxel volume in blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI). Noise of physiological origin that is present in the voxel time course is a prohibitive factor in the detection of small activation-induced BOLD signal changes. If the physiological noise contribution dominates over the temporal fluctuation contribution in the imaging voxel, further increases in the voxel signal-to-noise ratio (SNR) will have diminished corresponding increases in temporal signal-to-noise (TSNR), resulting in reduced corresponding increases in the ability to detect activation induced signal changes. On the other hand, if the thermal and system noise dominate (suggesting a relatively low SNR) further decreases in SNR can prohibit detection of activation-induced signal changes. Here we have proposed and called the “suggested” voxel volume for fMRI the volume where thermal plus system-related and physiological noise variances are equal. Based on this condition we have created maps of fMRI suggested voxel volume from our experimental data at 3T, since this value will spatially vary depending on the contribution of physiologic noise in each voxel. Based on our fast EPI segmentation technique we have found that for gray matter (GM), white matter (WM), and cerebral spinal fluid (CSF) brain compartments the mean suggested cubical voxel volume is: (1.8 mm)3, (2.1 mm)3 and (1.4 mm)3, respectively. Serendipitously, (1.8 mm)3 cubical voxel volume for GM approximately matches the cortical thickness, thus optimizing BOLD contrast by minimizing partial volume averaging. The introduced suggested fMRI voxel volume can be a useful parameter for choice of imaging volume for functional studies.
Error Mechanisms in Indoor Positioning Systems without Support from GNSS

There exist various applications for indoor positioning, amongst which indoor positioning and tracking in urban environments has gained significant attention. Some user communities, like fire fighters, ideally require indoor accuracy of less than one metre, with accuracies of less than six metres acceptable by some other user communities. Achieving this level of accuracy requires a detailed profiling of error sources so that they can be better understood so that, in turn, indoor positioning accuracy in the presence of these errors can be further improved. Some well known error sources like multipath, NLOS (non line of sight), oscillator drift, dilution of precision and others have been studied and can be found in the literature. A less well known error source that can substantially affect indoor positioning accuracy are the effects of the dielectric properties of building materials on propagation delay. Various RF and non-RF based prototypes that claim to be suitable for indoor positioning can be found in the literature. Most of the existing literature discusses algorithms and summarizes the positioning results that were achieved during field tests using a prototype system or, more commonly, simulations. Little of this existing literature provides a breakdown of the total navigation system errors observed with the objective of analyzing the contribution of each error source independently. The paper will first provide a brief overview of the precision personnel locator system developed at the Worcester Polytechnic Institute. The field tests and observed indoor positioning results using this RF prototype will then be summarized and used to provide a baseline to establish a system error budget. The total observed error will be broken down and a detailed analysis of each of the error sources will be presented based on actual measured data in a variety of indoor environments. This leads to a better understanding of how each error source affects indoor positioning accuracy. Each of the error sources can then be independently optimized to minimize the observed errors. Specifically, the interplay between the dielectric properties and multipath profiles will be highlighted. This paper will conclude by presenting an error budget which can be used as a practical lower bound when designing precise indoor positioning systems.
Assessing life cycle environmental implications of polymer nanocomposites

Research into the holistic evaluation of emerging nanotechnologies using systems analysis is pivotal for guiding their safe and sustainable development. This work presents the first energetic life cycle assessment of polymer nanocomposites (PNCs) that evaluates both thermoplastic and thermoset resins. Both simple carbon nanofiber (CNF) and carbon nanofiber-glass fiber (CNF-GF) hybrid nanocomposites are evaluated and compared with steel. The issue of life cycle inventory is tackled based on published literature and best available engineering information. A cradle-to-gate comparison reveals that CNF reinforced PNCs are 1.3-10 times more energy intensive than steel and thus the product use phase is likely to govern whether any net savings in life cycle energy consumption can be realized for PNC based products. A case study involving the use of CNF and CNF-GF reinforced PNCs in the body panels of automobiles is further presented and highlights that the use of PNCs with lower CNF loading ratios may result in net life cycle fossil energy savings relative to steel. Other factors such as cost, toxicity impact of CNF, and end-of-life issues specific to CNFs need to be considered to evaluate the final economic and environmental performance of CNF reinforced PNC materials. The results of this study can easily be used for evaluating other CNF based PNC applications.
Robust control of a class of nonlinear uncertain systems

Robust control of a general class of uncertain nonlinear systems is investigated. The class of nonlinear systems includes many physical systems as special cases and has an important feature that the uncertainties in the system do not satisfy the matching conditions. Several robust control laws are proposed to make the system stable in the sense of either asymptotic stability or uniformly ultimately bounded stability. The results require no knowledge about the structure of the uncertainties. Although the uncertainties are assumed to be bounded in the Euclidean norm by a polynomial-type bounding function, there is no size restriction imposed on the bounding functions of the uncertainties. The extension to the trajectory tracking problem is also discussed. >