cssi/SciSciGPT-SciSciNet huggingface dataset:
Low complexity multi-user rate region maximization for frequency-selective interference channel

Multi-user rate region maximization for the interference channel has attracted great attention recently. However, close to optimal performance algorithms have high complexity, while the fast and distributed algorithms such as the iterative waterfilling algorithm suffer from poor performances, especially when the interferences are severe. Moreover, a lot of works deal with the case when the number of sub-channels L is equal to one, or perform well with a large number L (i.e. asymptotic case). Few works investigate the optimality under the small and finite L. For networks like cognitive radios, the secondary users can only sense a limited number of available sub-channels. As a result, rate region maximization for finite number of sub-channels becomes an issue of vital importance. In this paper, we propose a heuristic solution for the rate region maximization with low complexity and high performance. The basic idea is to select a limited set of combinations of subchannel assignments which most likely achieve the boundary of the rate region, and then construct the convex hull based on the iterative distributed solution. The complexity of the proposed algorithm is O(N2L2 log L) (without multilevel searches in the Optimal Spectrum Balancing (OSB) algorithm), where N is the number of users. Simulation results show that the proposed scheme can achieve performances comparable to those of a full search solution and OSB solution, and significantly better than the iterative waterfilling scheme in the high interference case.
Mucosal protection through active intestinal secretion: neural and paracrine modulation by 5-hydroxytryptamine

5-Hydroxytryptamine (5-HT) is widely distributed within enteroendocrine cells and neurons of the digestive tract. It stimulates active anion secretion in the intestinal epithelium, an effect which promotes the dilution and elimination of luminal pathogens. The intestinal secretory effects of 5-HT appear to be mediated in part by epithelial 5-HT2 like receptors that are linked to phosphatidylinositol turnover. In addition, 5-HT appears to interact with 5-HT3 or 5-HT4 receptors on submucosal neurons to elicit neuronal depolarization and an associated increase in intestinal secretion. Although the precise cellular mechanisms by which 5-HT modulates mucosal ion transport are incompletely understood, it is clear that 5-HT plays an important role as a intestinal secretagogue in certain diarrheal states, in laxation, and in intestinal hypersensitivity reactions.
Analysis of TGF-β1 and TGF-β3 as regulators of encephalitogenic Th17 cells: Implications for multiple sclerosis.

The phenotype of the CD4+ T cells that mediate the CNS pathology in multiple sclerosis is still unclear, and yet a vital question for developing therapies. One of the conundrums is the role of TGF-β in the development of encephalitogenic Th17 cells. In the present study, TGF-β1 and TGF-β3 were directly compared in their capacity to promote the differentiation of myelin-specific Th17 cells that could induce experimental autoimmune encephalomyelitis (EAE). Myelin-specific CD4+ T cell receptor transgenic cells differentiated with antigen in the presence of IL-6+TGF-β1 or IL-6+TGF-β3 generated T cells that produced robust amounts of IL-17, but were incapable of inducing EAE when transferred into mice. Further analysis of these non-encephalitogenic Th17 cells found that they expressed lower amounts of GM-CSF or IL-23R, both molecules necessary for encephalitogenicity. Thus, TGF-β, irrespective of isoform, negatively regulates the differentiation of encephalitogenic Th17 cells.
Progesterone modulation of transmembrane helix-helix interactions between the α-subunit of Na/K-ATPase and phospholipid N-methyltransferase in the oocyte plasma membrane

Background Progesterone binding to the surface of the amphibian oocyte initiates the meiotic divisions. Our previous studies with Rana pipiens oocytes indicate that progesterone binds to a plasma membrane site within the external loop between the M1 and M2 helices of the α-subunit of Na/K-ATPase, triggering a cascade of lipid second messengers and the release of the block at meiotic prophase. We have characterized this site, using a low affinity ouabain binding isoform of the α1-subunit.
A Dynamic Organic Structuring-Directing Agent for Pure-Silica-Zeolite AST and LTA Syntheses

Pure-silica-zeolite (PSZ) AST and LTA are synthesized successfully by using the same structure-directing agent (SDA) molecule, but at different concentrations. A dynamic organic SDA is proposed to discuss the mechanism of phase discrimination between AST and LTA. Data suggest that the SDA molecules can self-assemble into dimer or trimer complexes at different concentrations by π-π interactions, and these differences can be taken advantage of to selectively synthesize either PSZ AST or LTA. These deviations from the Liebau's rules indicate that small changes in SDA chemistry, structure, and order in solution can have a great impact on the structure selectivity of the zeolite synthesis.
Fiber-lattice accumulator design considerations for optical ΣΔ analog-to-digital converters

Integrated optical sigma-delta (??) analog-to-digital converters (ADCs) use a pulsed laser to oversample an input signal at two Mach-Zehnder interferometers. A fiber-lattice accumulator is embedded within a feedback loop around a single-bit quantizer to spectrally shape the quantization noise to fall outside the signal band of interest. Decimation filtering is applied to the quantizer output to construct the input signal with high resolution. Applications of integrated optical ?? ADCs include digitizing wideband radio-frequency signals directly at an antenna (digital antenna). In this paper, a novel fiber-lattice accumulator design is presented, and a coherent simulation of an integrated optical first-order, single-bit ?? ADC is reported. The accumulator leakage resulting from a mismatch in the optical circuit parameters is quantified. A time-domain analysis is presented, and the simulation results from an all-electronic ?? ADC are presented for comparison. A frequency-domain analysis of a ten times oversampling (n = 4 bits) simulation is used to compare the dynamic performance parameters, including the spurious-free dynamic range, signal-to-noise-plus-distortion ratio, and effective number of bits. The formation of image frequencies when the accumulator is overloaded (i.e., the optical amplifier gain is too large) is also investigated.
Intra-reader reliability of FDG PET volumetric tumor parameters: effects of primary tumor size and segmentation methods.

To establish the effects of size and segmentation methods on intra-reader reliability of primary tumor metabolic tumor volume (MTV) and total glycolytic activity (TGA) in human solid tumors. This is a retrospective study of 121 patients who had a baseline FDG PET/CT scan for oncologic staging. Volumetric parameter readings were performed in random order on two separate occasions, 12 weeks apart, by the same reader. The MTV and TGA were segmented using gradient and fixed maximum standardized uptake value (SUVmax) threshold methods. Intra-reader reliability was established by the intraclass correlation coefficient (ICC) and Bland–Altman analysis. The biases for MTV were 2.95, 14.76 and 11.13 % for gradient segmentation, 38 and 50 % SUVmax fixed threshold segmentations, respectively (p < 0.0001). For TGA, the corresponding biases were 0.76, 10.36 and 7.46 % (p < 0.0001). There were no statistically significant differences in the biases between the first and second reads for MTV segmented for small and large volume tumors by the gradient method (p < 0.34) or 50 % SUVmax threshold segmentation (p < 0.08). However, there were statistically significant differences in the corresponding biases for the 38 % SUVmax threshold segmentation (p < 0.04). There were no statistically significant differences in the biases between the first and second reads for TGA segmented for small and large volume tumors (p < 0.98). Intra-reader reliability for primary tumor FDG MTV and TGA is affected by the tumor size and segmentation methods. The segmentation bias was smaller for gradient method than percentage fixed threshold method for MTV. The segmentation biases were smaller for TGA than MTV.
MINIMIZING SURGICAL PROBLEMS OF PERITONEAL DIALYSIS IN CHILDREN

We review our experience with peritoneal dialysis catheter placement in children. The most common surgical problems after peritoneal dialysis catheter placement are inguinal hernias, catheter obstruction and dialysate leakage. We describe specific techniques to minimize the development of these problems.
Designing and developing an automatic interactive keyphrase extraction system with Unified Modeling Language (UML)

Designing and developing a system that assists the users in digesting and understanding information available has been a difficult challenge. In this paper, we discuss the design and development of an automatic interactive keyphrase extraction system, called KPSpotter, which is capable of processing various formats of data such as XML, HTML, and plain text through Internet. KPSpotter combines Information Gain data mining measure and several Natural Language Processing (NLP) techniques, such as Part of Speech (POS) technique and First Occurrence of Term. To improve extraction accuracy, WordNet is incorporated into KPSpotter. In designing and developing KPSpotter we utilized Unified Modeling Language (UML). UML modeling helps in the formalization of the preliminary analysis model and accomplishes iterative system design and development. We also conducted experiments for system performance testing by comparing keyphrases extracted by KPSPotter and KEA, a well-known naive Baysiean-based keyphrase extraction system. The experiments show that KPSpotter outperforms KEA in most test cases.
Prophylaxis and treatment of influenza.

IT has been over 20 years since there has been a severe influenza pandemic. Nevertheless, influenza remains an important epidemic viral infection with the potential to return to its former magnitude.1 2 3 4 The Centers for Disease Control documented 10,000 or more excess deaths in the United States in each of 19 epidemics from 1957 to 1986, and more than 40,000 deaths in several of them.5 The major causes of death are pneumonia and the exacerbation of cardiopulmonary and other conditions,6 7 8 9 10 and 80 to 90 percent of those who die are 65 years of age or older. In addition, substantial morbidity occurs . . .
Processor-Controlled Microdensitometry

A new scheme of densitometric data collection is described which comprises a digital filtering technique and process control program. A 6502-based PET 2001/32K microcomputer and an Elscan model 2500 specular microdensitometer are interfaced through the standard 6522 VIA port chip. An Analog Devices ADC80/12 monolithic A/D converter is used to digitize the analog output of the light photometering system. Additionally, control of the optical scanner assembly is provided through processor-driven 4-phase TTL logic circuitry. The technique applies to any analog signal of interest, either for filtering purposes or for recording directly into memory for later waveform or transient analysis. The maximum data gathering rate is 40 kHz, limited by the A/D conversion time of 25 μs.
Evolutionary Origins for Social Vocalization in a Vertebrate Hindbrain–Spinal Compartment

The macroevolutionary events leading to neural innovations for social communication, such as vocalization, are essentially unexplored. Many fish vocalize during female courtship and territorial defense, as do amphibians, birds, and mammals. Here, we map the neural circuitry for vocalization in larval fish and show that the vocal network develops in a segment-like region across the most caudal hindbrain and rostral spinal cord. Taxonomic analysis demonstrates a highly conserved pattern between fish and all major lineages of vocal tetrapods. We propose that the vocal basis for acoustic communication among vertebrates evolved from an ancestrally shared developmental compartment already present in the early fishes.
Chromatic capacity and graph operations

The chromatic [email protected]"c"a"p(G) of a graph G is the largest k for which there exists a k-coloring of the edges of G such that, for every coloring of the vertices of G with the same colors, some edge is colored the same as both its vertices. We prove that there is an unbounded function f:N->N such that @g"c"a"p(G)>=f(@g(G)) for almost every graph G, where @g denotes the chromatic number. We show that for any positive integers n and k with k=~, where K"n^r is the complete n-partite graph with r vertices in each part. Finally, for any positive integers p and q we construct a graph G with @g"c"a"p(G)[email protected](G)=p that contains no odd cycles of length less than q.
Historical land use and soil analysis guiding corridor landscape design

Changing land use from forested environments to agricultural and/or urban spaces dramatically alters soil chemical, physical, and biological properties and thereby influences the survivability of landscape plants installed in these areas. This site analysis was conducted along New Hope Road, in Pickens County, SC, to develop a sustainable landscape design for the greenway corridor to buffer future cuttings of pines and offer a variety of recreational and educational opportunities for the community. Using a “design with nature” framework, an interdisciplinary team collaborated on a thorough observation and analysis of the inherent qualities of the site, historical documents and aerial photographs to describe the land use history of the site. The dominant soil series found on the site were Cecil clay loam, Cecil sandy loam, and Pacolet clay loam. Surface soil chemistry tests were conducted to examine soil and buffer pH; organic carbon and nitrogen contents; nitrate–nitrogen; extractable phosphorus, potassium, calcium, magnesium, zinc, manganese, copper, boron, and sodium; lime requirements and recommendations; cation exchange capacity; acidity; and percent base saturation. Analysis of site history, aerial photographs, and soil testing revealed that a history of intensive agricultural land use and managed forestry on the site has noticeably altered the soil quality. Severe soil erosion and compaction brought about by a combination of anthropogenic and natural causes have left much of the site with infertile soils lacking a true topsoil layer and characterized by low pH. These qualities present numerous challenges when attempting to modify and install vegetation. Based on historical land use, soil analysis, and plant species characteristics, a final landscape design was created that addressed the environmental opportunities, constraints of the site and provided site- and plant-specific fertilizer recommendations for successful establishment and maintenance of this greenway corridor.
Site-specific twelve-lead ECG features to identify an epicardial origin for left ventricular tachycardia in the absence of myocardial infarction.

Background Identification of an epicardial origin for left ventricular tachycardia (LV-VT) based on electrocardiogram (ECG) criteria facilitates the approach to catheter ablation. Reported criteria, although helpful, may not apply uniformly to all LV regions. Objective We hypothesized that unique region-specific ECG patterns identify epicardial LV-VTs in patients without myocardial infarction. Methods The QRS morphologies during pace mapping from 402 epicardial and 234 comparable endocardial sites and 19 epicardial VTs were analyzed in 15 patients with respect to morphology and duration of all and components of the QRS. Results Basal superior (N = 244) and apical superior (N = 141) pace mapping sites showed Q wave in lead I more commonly from epicardial vs corresponding endocardial sites (90% vs 16%, 88% vs 26% respectively; P P = .002. Basal inferior (N = 140) and apical inferior (N = 76) epicardial sites showed Q wave in leads II-III-aVF (81% vs 37%, 92% vs 33%, P P Conclusion ECG features distinguishing epicardial LV-VT are site specific, including the presence or absence of a Q wave in leads that reflect local ventricular activation.
Temporal and spatial distributions of sediment mercury at salt pond wetland restoration sites, San Francisco Bay, CA, USA.

Abstract Decommissioned agricultural salt ponds within south San Francisco Bay, California, are in the process of being converted to habitat for the benefit of wildlife as well as water management needs and recreation. Little is known of baseline levels of contaminants in these ponds, particularly mercury (Hg), which has a well established legacy in the Bay. In this study we described spatial and short-term temporal variations in sediment Hg species concentrations within and among the Alviso and Eden Landing salt ponds in the southern region of San Francisco Bay. We determined total Hg (Hg t ) and methylmercury (MeHg) in the top 5 cm of sediment of most ponds in order to establish baseline conditions prior to restoration, sediment Hg t concentrations in a subset of these ponds after commencement of restoration, and variation in MeHg concentrations relative to sediment Hg t , pH, and total Fe concentrations and water depth and salinity in the subset of Alviso ponds. Inter-pond differences were greatest within the Alviso pond complex, where sediment Hg t concentrations averaged (arithmetic mean) 0.74 μg/g pre and 1.03 μg/g post-restoration activity compared to 0.11 μg/g pre and post at Eden Landing ponds. Sediment Hg t levels at Alviso were fairly stable temporally and spatially, whereas MeHg levels were variable relative to restoration activities across time and space. Mean (arithmetic) sediment MeHg concentrations increased (2.58 to 3.03 ng/g) in Alviso and decreased (2.20 to 1.03 ng/g) in Eden Landing restoration ponds during the study. Differences in MeHg levels were related to water depth and pH, but these relationships were not consistent between years or among ponds and were viewed with caution. Factors affecting MeHg levels in these ponds (and in general) are highly complex and require in-depth study to understand.
Re-measuring left–right: A comparison of SEM and Bayesian measurement models for extracting left–right party placements

Abstract This paper demonstrates the relative strengths and weaknesses of SEM and Bayesian approaches to combining different sources of data when estimating latent variables. Data on party left–right positioning collected from party manifestos and surveys of party experts, MPs and voters are used to illustrate the two techniques. Although widely used and accepted, the SEM approach is less useful than the Bayesian approach, particularly when using the latent variable in subsequent predictive estimations.
SSD: Smooth Signed Distance Surface Reconstruction

We introduce a new variational formulation for the problem of reconstructing a watertight surface defined by an implicit equation, from a finite set of oriented points; a problem which has attracted a lot of attention for more than two decades. As in the Poisson Surface Reconstruction approach, discretizations of the continuous formulation reduce to the solution of sparse linear systems of equations. But rather than forcing the implicit function to approximate the indicator function of the volume bounded by the implicit surface, in our formulation the implicit function is forced to be a smooth approximation of the signed distance function to the surface. Since an indicator function is discontinuous, its gradient does not exist exactly where it needs to be compared with the normal vector data. The smooth signed distance has approximate unit slope in the neighborhood of the data points. As a result, the normal vector data can be incorporated directly into the energy function without implicit function smoothing. In addition, rather than first extending the oriented points to a vector field within the bounding volume, and then approximating the vector field by a gradient field in the least squares sense, here the vector field is constrained to be the gradient of the implicit function, and a single variational problem is solved directly in one step. The formulation allows for a number of different efficient discretizations, reduces to a finite least squares problem for all linearly parameterized families of functions, and does not require boundary conditions. The resulting algorithms are significantly simpler and easier to implement, and produce results of quality comparable with state-of-the-art algorithms. An efficient implementation based on a primal-graph octree-based hybrid finite element-finite difference discretization, and the Dual Marching Cubes isosurface extraction algorithm, is shown to produce high quality crack-free adaptive manifold polygon meshes.
Low infusion rate digital subtraction angiography to predict regional perfusion in hepatic arterial chemotherapy.

Digital substraction angiography (DSA) with a low injection rate of contrast (0.5 ml/sec) was studied as a means of predicting the regional perfusion of percutaneously placed catheters for hepatic arterial chemotherapy. In 64 hepatic artery catheter placements, conventional injection rate angiography (3–5 ml/sec) and low infusion rate DSA exams were compared to conventional radionuclide perfusion studies performed with Tc-99m-MAA. In 58 of 64 cases (90.6%) the conventional arteriogram correctly predicted the extent of hepatic perfusion, whereas in 63 of 64 cases (98%), the low flow DSA exam correctly predicted hepatic perfusion. The conventional arteriogram correctly predicted the extent of extrahepatic perfusion in 32 cases (50%), with a sensitivity of 100%, but a specificity of only 39.6%. The DSA exam was correct in defining the presence or absence of extrahepatic perfusion in 57 of 64 cases for a sensitivity of 82% and a specificity of 91%. Despite the quantitative difference between the low infusion rate DSA study and the chemotherapy infusion (10 ml/hr), it is a useful tool to assist in the correct positioning of temporary catheters for hepatic arterial chemotherapy.
ADENOTONSILLAR HEMORRHAGE CAUSED BY ALTERATION OF PERIPHEROVASCULAR DYNAMICS DUE TO PARTIAL AIRWAY OBSTRUCTION.

Abstract An interesting case of the management of near fatal hemorrhage after adenotonsillectomy is presented. The factor of partial airway obstruction has been implicated and is open to debate. Investigation reveals that increases in intrapulmonary pressures and small changes in peripherovascular pressures can produce undesirable manifestations pointing up the continued need for careful monitoring of the airway both during and after oral surgery. Tracheostomy with pressure packing of the posterior nasopharynx must be considered an important part in control of severe adenotonsillar hemorrhage.
A case series of transformation of teratoma to primitive neuroectodermal tumor: evolving management of a rare malignancy.

Primitive neuroectodermal tumor (PNET) is a pathologic diagnosis that encompasses several different tumor types, including central nervous system tumors and Ewing’s sarcomas. Teratoma, a common element of germ cell tumor (GCT), has the ability to transform to malignant PNET in a small number of patients. Making a definitive diagnosis of PNET is difficult given its deviation from elements of GCT and its non-specific pathologic findings. Establishing the diagnosis is crucial as PNETs respond poorly to standard platinum-based chemotherapy used for treatment of GCT. Primary treatment for PNET is surgical, though this is often not feasible in many patients due to extensive disease at diagnosis. As an alternative, chemotherapy regimens traditionally used for Ewing’s sarcoma, such as vincristine, doxorubicin and cyclophosphamide alternating with ifosfamide and etoposide, have shown limited efficacy in the neoadjuvant, adjuvant, and palliative settings. Future research should delineate the genetic underpinnings of PNET and develop therapeutic options accordingly.
Hippocampal synaptic plasticity as a biological substrate underlying episodic psychosis

Structural change in the hippocampal formation has become popular as a proposed neurobiological substrate for schizophrenic disorders. It is postulated that behavioral plasticity in the form of long-term potentiation of hippocampal synaptic transmission is an attractive putative mechanism for the mediation of transient psychosis. Moreover, the disturbed hippocampal neuroarchitecture found in schizophrenic brain may be susceptible to potentiation and dysfunctional to the degree that delusions and hallucinations develop. Partial and selective blockade of the receptors mediating potentiation may prove to be an efficient means of preventing psychotic episodes and avoiding further damage to the involved network. Basic research, utilizing experimental models such as intraventricular kainic acid injection, may help to clarify the anatomical and physiological substrate of psychosis.
Firm growth patterns: examining the associations with firm size and internationalization.

Abstract Understanding the growth patterns of an industry is essential for establishing sustainable growth strategies. However, until recently little had been known about restaurant firm growth patterns. Thus, this study examined the growth patterns of restaurant firms in association with firm size class and internationalization, after controlling for total and long-term debt leverage, retained earnings, and growth opportunity. Overall, the results of this study showed that small restaurant firms grow faster than large restaurant firms but the growth rate decreases as firm size increases. Furthermore, the growth rate of large firms decreased more slowly than small firms. In terms of internationalization, this study found that as firm size increases, the growth rate of small international firms decreases more rapidly than that of small domestic firms. However, the growth rate of large international firms decreases more slowly than that of large domestic firms. These findings indicate the appropriateness of internationalization strategies for large restaurant firms but the inappropriateness of these strategies for small firms. More detailed results and discussion are also provided.
Quantitative Assessment of Infrared Analysis of Concrete Admixtures

This study investigates quantitative methods for assessment of infrared analysis of concrete admixtures using correlation coefficients by performing IR scans following the ASTM C494/C494M-11 specifications. In order to achieve this goal, numerous IR scans were performed on specimens supplied by the manufacturer from different batches to ensure uniformity and equivalency. These scans were then analyzed to create correlation coefficients for each admixture. The correlation coefficients were used to quantitatively evaluate and interpret IR Scans of job samples. The study focused on 23 most commonly used concrete admixtures by the New Jersey Department of Transportation (NJDOT). They include air-entrainers, accelerators, retarders, water reducers, and other combinations of these admixtures. Their correlation coefficients were established by analyzing a total of 12 scans of each admixture from three different batches supplied by the manufacturer at different time intervals. In order to validate the obtained correlation coefficients and establish a target correlation, job samples were tested and compared to the obtained correlations. The study also evaluated the effects of drying time and using different types of KBr on correlation coefficients.
Native Plants and Native Peoples: A Community Workshop at the Sam Noble Museum

This project report describes a workshop—Native Plants and Native Peoples—held on August 8, 2014 at the Sam Noble Museum, University of Oklahoma.
Mesoscale Gravity Wave Variances from AMSU-A Radiances

A variance analysis technique is developed here to extract gravity wave (GW) induced temperature fluctuations from NOAA AMSU-A (Advanced Microwave Sounding Unit-A) radiance measurements. By carefully removing the instrument/measurement noise, the algorithm can produce reliable GW variances with the minimum detectable value as small as 0.1 K2. Preliminary analyses with AMSU-A data show GW variance maps in the stratosphere have very similar distributions to those found with the UARS MLS (Upper Atmosphere Research Satellite Microwave Limb Sounder). However, the AMSU-A offers better horizontal and temporal resolution for observing regional GW variability, such as activity over sub-Antarctic islands.
Discrete Nebulization for Sample Introduction of High Salt Solutions in Flame Atomic Absorption Spectrometry

Abstract The detection of copper in high salt solutions using flame atomic absorption spectrometry with discrete nebulization of microliter volumes compared to conventional continuous nebulization for sample introduction was investigated. Using continuous nebulization, a decrease in absorbance signal and uptake rate with increasing salt concentration, a detection limit of 0.02 μg/mL for copper, and precision deteriorating with increasing salt concentration in the 1–3% range was found. Discrete nebulization showed similar trends with decreasing absorbance signal with increasing salt concentration, but had the advantage that the microliter volumes used prevented clogging of the burner. At low microliter volumes and high salt concentrations, the precision deteriorated to around 10% and detection limit to 0.3 pg/mL. The technique was rapid, simple and did not produce memory effects.
Water balance and kidney function in the least shrew (Cryptotis parva)

We assessed renal function in least shrews (Cryptotis parva, body mass 4.7 g) within the context of overall water balance. The glomerular filtration rate (GFR) of shrews with unlimited food and water was 2.4 ml/h, about 60% of the rate predicted from body mass. Of this, about 3% (0.075 ml/h) was excreted as urine with an osmolality of 1944 mmol/kg, 5.5 times plasma osmolality. Shrews had a total water turnover (5 ml/day) two to three times higher than expected from allometry for a small mammal of this size. Water influx was partitioned among preformed water from food (65%), drinking (16%), and metabolic water (20%). Water efflux was divided among urine flow (35%), fecal water loss (estimated as 23%), and evaporation (by difference, 42%). Least shrews had a high water turnover rate and relatively high urine flow rate (UFR); this likely reflects a combination of factors, including high metabolism, active lifestyle, and wet diet.
Preservation and detection of microstructural and taxonomic correlations in the carbon isotopic compositions of individual Precambrian microfossils

Abstract Here we present techniques for, and new data from, in situ carbon isotope (δ13C) analysis of Precambrian permineralized microscopic fossils with a reproducibility of 1–2‰ using secondary ion mass spectrometry (SIMS). Individual microfossils, selected for their excellent preservation, were analyzed in petrographic thin sections of stromatolitic cherts from the Proterozoic Gunflint (∼1880 Ma), Bitter Springs (∼830 Ma), Min’yar (∼740 Ma), and Chichkan (∼775 Ma) Formations. The range of δ13C values (−34.6‰ to −22.1‰ VPDB) among the 46 individuals analyzed falls within that expected for photoautotrophic carbon fixation by ribulose bisphosphate carboxylase (RuBisCO), consistent with morphology-based taxonomic assignments for these specimens. Microfossils classified as cyanobacteria from the Gunflint, Bitter Springs, and Min’yar Formations (for which published carbonate carbon isotope data can be used to estimate the δ13C of the original dissolved inorganic carbon substrate) exhibit a consistent ∼19‰ total fractionation (δ13C of dissolved inorganic carbon − δ13C of biomass) similar to that observed in living cyanobacteria, over a wide range of δ13Ccarb values (−2.9‰ to 3.4‰). In stromatolitic chert of the Min’yar Formation, morphologically diverse microfossils preserved in a ∼1 mm2 part of a microbial mat exhibit systematic isotopic differences among and within taxa that correlate with their morphologically inferred biological affinities and suggest that isotopic signatures of their original biosynthetic processes (e.g., lipid and peptidoglycan synthesis) are preserved. Isotopic offsets consistent with the different RuBisCO-based fractionations typical of cyanobacteria and photosynthetic eukaryotes are documented by the differing δ13C values of a colonial cyanobacterium (−22.6 ± 0.5‰) and a phytoplanktonic protistan acritarch (−28.9 ± 1.0‰) situated
Catalyzing Investment for Domestic Impact: The Impact Investing Initiative of the U.S. Small Business Administration

In January 2011, the U.S. Small Business Administration (SBA) announced its one billion dollar Impact Investment Initiative, which will match private capital raised by investment funds that focus explicitly on making impact-oriented investments in small businesses. Reaction to the announcement has been a combination of excitement and skepticism, and it has raised myriad questions: What brings SBA to the impact investing space? Why now? How is it going to work? How does SBA fit into this space? This essay aims to answer those questions. We start by recognizing that SBA is a relative newcomer to the impact investing space and that it approaches this new investment realm from a very different starting point than the organizations that have been studying and investing in this space for years. SBA has broad experience with entrepreneurs and small businesses, and with investment funds and capital markets. This experience has led to three key conclusions: • There are meaningful opportunities and untapped potential in domestic impact investing. These opportunities exist over and above traditional areas of impact investing, such as microfinance or community development finance— that is, in the private equity industry. • The current economic environment creates both a great need for more impact investment and a formidable set of challenges to making it happen. • Finally, public-private partnerships can play a critical role in catalyzing investment, but creating these partnerships will require entrepreneurial and innovative approaches to how we attempt to stimulate more entrepreneurship and innovation.
Residues in Colostrum Following Antibiotic Dry Cow Therapy

Abstract Cows from five dairy herds were used to determine persistence of antibiotic residues in colostrum and milk following dry cow therapy. Cows were treated in all quarters at drying off with antibiotics approved for use for nonlactating cows. Antibiotics procaine penicillin G plus dihydrostreptomycin, novobiocin, cloxacillin, or cephapirin were compared with no treatment. Composite colostrum samples were collected from each cow at first milking after parturition. Samples were screened for residues by Delvotest P. Colostrum samples positive by Delvotest also were tested by Bacillus stearothermopbilus disc assay. Four of 186 colostrum samples from cows treated with antibiotics at drying off were positive for residues by Delvotest. Only one was confirmed positive by disc assay following heat treatment. All colostrum samples from 48 cows not treated were negative. Samples of first marketable milk also were collected. Over 96% of milk samples from cows treated at drying off and 100% of milk samples from cows not treated were negative for residues by Delvotest. If manufacturer's recommendations are followed, antibiotic residues in colostrum and milk following dry cow therapy with products in our study should not be a significant problem.
EFFECT OF EJACULATION ON SERUM TOTAL AND FREE PROSTATE-SPECIFIC ANTIGEN CONCENTRATIONS

Abstract Objectives Measurement of total serum prostate-specific antigen (PSA) is widely used as an aid to early detection of prostate cancer. Measurement of the ratio of free to total PSA may increase the specificity of PSA testing. To improve specificity further, other factors that may cause transient increases in PSA, such as ejaculation, have been identified. We prospectively studied the effect of ejaculation on total and free PSA levels and examined whether changes induced by ejaculation would affect recommendations for performing prostatic biopsy. Methods We measured the baseline total and free serum PSA levels and obtained measurements 1, 6, and 24 hours after ejaculation in 20 volunteers (mean age 59 years). All men had baseline PSA levels less than 4.0 ng/mL We used repeated-measures analysis of variance to test for changes in total, free, and percent free PSA after ejaculation. We also calculated the proportion of men with PSA levels greater than the expected biologic variability at each timepoint. Results The mean total, free, and percent free serum PSA increased 1 hour after ejaculation. Mean total PSA levels remained significantly increased 6 and 24 hours after ejaculation. Mean free PSA decreased to baseline levels by 6 hours after ejaculation, and percent free PSA returned to baseline by 6 hours after ejaculation and then decreased below baseline by 24 hours. When normal biologic variation was accounted for, 40% of men, at 24 hours after ejaculation, had total PSA levels above the baseline level. Similarly, 24 hours after ejaculation, the percent free PSA remained above baseline level in 10% and below baseline level in 35% of the men. Conclusions Both total and free PSA increase immediately after ejaculation, with differing rates of return to baseline levels. PSA testing within 24 hours after ejaculation may lead to an erroneous interpretation of the results of both total and percent free PSA measurements in a small proportion of men.
Toxicity of coal gasifier solid waste to the aquatic plants Selenastrum capricornutum and Spirodela oligorhiza.

Classical assessment of aquatic toxicity has focused on fish and invertebrates primarily due to their economic importance. However, increased awareness of the role of aquatic vegetation as primary producers in aquatic systems has stimulated their use in aquatic hazards evaluations. This paper presents the results of solid waste leaching tests using a procedure which was designed to mimic landfilling of solid waste. Results are reported for leachate analysis of the ash agglomerate and the relative toxicity of this leachate to Selenastrum capricornutum (a unicellular green alga) and Spirodela oligorhiza (a floating aquatic vascular plant).
Kinetics of methanol-steam reformation in an internal reforming fuel cell

Abstract A study of the kinetics of the methanol-steam reformation reaction within an idealized tube reactor and within a non-ideal internal reforming fuel cell (IRFC) was performed. Kinetic expressions were calculated from the reaction rate data obtained from the tube reactor by least squares fitting to general power law model, as well as to a mechanism-based model put forth by Peppley et al. [Appl. Catal. A 179 (1999) 21; Appl. Catal. A 179 (1999) 31] assuming isothermal plug flow behavior. Reaction rate data obtained from an IRFC with and without an H 3 PO 4 containing membrane electrode assembly (MEA) was compared to the reaction rates predicted by the kinetic model. It was found that methanol conversion rates in the IRFC were significantly less than would be for an ideal plug flow reactor (PFR) with an equal amount of catalyst due to the non-ideal flow through the reactor bed. However, despite the non-ideal flow caused by the design compromises inherent in an IRFC and the resulting drop in effective catalyst activity, it was projected that for fuel cell systems with a current density greater than 400 mA cm −2 , the IRFC would require less catalyst mass than a traditional system with external reformer. This is the result of an experimentally verified accelerated methanol conversion rate in the IRFC caused by the extraction of H 2 from the reforming reactor bed. Long-term stability of the IRFC due to acid leaching still needs to be addressed. Additionally, the extraction of H 2 from the reformer bed, which occurs in the IRFC, introduces concerns of failure due to coking.
Syndrome of congenital absence of the spleen with associated cardiovascular and gastroenteric anomalies.

Survey of 27 cases in the literature and the authors' 3 cases reveals a characteristic syndrome of congenital absence of the spleen with certain cardiovascular and gastrointestinal abnormalities. The hematologic and other findings permit a presumptive antemortem diagnosis. More accurate prognosis is made possible and valuable information is afforded the cardiac surgeon, since the cardiac anomalies often follow a predictable pattern.
Fisheries self-governance: corporate or cooperative structures?

Abstract The concept of self-governance of fisheries resources has implicitly assumed that self-governance would be democratic in structure. This concept of self-governance is a patterned on the democratic governance of cooperatives. The present analysis argues for a corporate concept of fisheries self-governance. A corporate governance structure provides a vehicle for effective joint decision-making by producers, but avoids the inefficient longrun incentives created by a cooperative governance structure.
Cholera and Other Vibrioses in the United States

CHOLERA is no stranger to the United States. Cases were identified in this country during four of the seven worldwide cholera pandemics that have occurred since 1817: over 150,000 Americans died in 1832 and 1849 when the protracted second cholera pandemic twice visited the United States; 50,000 died in 1866 during the fourth pandemic; and cases were reported in New York and Massachusetts in 1911, during the sixth pandemic.1 2 3 Within the past decade cases have again been reported in the United States,4 5 6 7 and cholera is now apparently endemic along the U.S. Gulf Coast.6 Vibrio species other than Vibrio cholerae have . . .
Why do contagion effects vary among bank failures

Abstract Many of the previous studies on contagion effects in the banking industry focused on the failure of a large bank to determine whether the adverse effects spread to other banks. Yet, little is known whether other publicized bank failures cause contagion effects, and why the effects may vary among bank failures. Given the changes in the banking environment over time, contagion effects could be conditioned on the characteristics of the failing bank and of the banking environment at that time. We assess 99 publicized bank failures over the 1980–1996 period, and find that contagion effects exist in general for the surviving rivals of the failed bank. The degree of contagion effects varies over time (among bank failures), and is stronger when the failed bank is a multibank holding company, when the failed bank is publicly held, when the failed bank is relatively large, when the rivals are relatively small, and when the rivals have relatively low capital levels. The contagion effects are less pronounced in the period following the passage of FIRREA. Furthermore, the total risk-shifts of surviving rival banks in response to the announcement of a failed bank are inversely related to their capital level, and total risk-shifts of rival banks are less pronounced for failures occurring just after the passage of FIRREA. The results suggest that a bank’s exposure to possible contagion effects due to a bank failure can be partially controlled by a bank’s managerial policies and by regulatory policies.
Regulation of Akt Signaling by Sirtuins Its Implication in Cardiac Hypertrophy and Aging

Cardiac hypertrophy is a multifactorial disease characterized by multiple molecular alterations. One of these alterations is change in the activity of Akt, which plays a central role in regulating a variety of cellular processes ranging from cell survival to aging. Akt activation is mainly achieved by its binding to phosphatidylinositol (3,4,5)-triphosphate. This results in a conformational change that exposes the kinase domain of Akt for phosphorylation and activation by its upstream kinase, 3-phosphoinositide-dependent protein kinase 1, in the cell membrane. Recent studies have shown that sirtuin isoforms, silent information regulator (SIRT) 1, SIRT3, and SIRT6, play an essential role in the regulation of Akt activation. Although SIRT1 deacetylates Akt to promote phosphatidylinositol (3,4,5)-triphosphate binding and activation, SIRT3 controls reactive oxygen species-mediated Akt activation, and SIRT6 transcriptionally represses Akt at the level of chromatin. In the first part of this review, we discuss the mechanisms by which sirtuins regulate Akt activation and how they influence other post-translational modifications of Akt. In the latter part of the review, we summarize the implications of sirtuin-dependent regulation of Akt signaling in the control of major cellular processes such as cellular growth, angiogenesis, apoptosis, autophagy, and aging, which are involved in the initiation and progression of several diseases.
Patología quirúrgica de la glándula tiroides

Introduccion: Debido a la gran diversidad de patologia quirurgica de la glandula tiroides y su alta frecuencia en nuestro medio, creemos conveniente presentar nuestra experiencia en esta patologia. Objetivos: Conocer la incidencia de la patologia quirurgica de la glandula tiroides, segun diagnostico anatomopatologico, en pacientes operados. Diseno: Estudio retrospectivo, observacional y descriptivo. Lugar: Servicio de cirugia de cabeza y cuello, Hospital Dos de Mayo, Lima, Peru, hospital de ensenanza medica. Participantes: Pacientes operados de la glandula tiroides. Intervenciones: Se reviso las historias clinicas de pacientes operados de la glandula tiroides, desde enero de 1997 hasta diciembre de 2006. Principales medidas de resultados: Resultados anatomopatologicos en los especimenes de glandula tiroides. Resultados: Hubo 274 casos operados, de los cuales 81,4% del total correspondio al sexo femenino; 56,9% de los casos provenia de fuera de Lima y Callao, con edades que fluctuaban desde los 30 y 59 anos. El tumor fue el signo predominante en 97,8% de los casos. La operacion realizada mas frecuente fue la tiroidectomia total (39,8%). La patologia benigna represento 58% de los casos, con el adenoma folicular como principal patologia benigna (23%); dentro de las neoplasias malignas (42% del total), 23,7% era carcinoma papilar. Conclusiones: La patologia tumoral tiroidea presento un marcado predominio en el sexo femenino, principalmente en los grupos etareos de la 4a, 5a y 6a decadas. La patologia glandular tiroidea fue en su mayoria benigna, y de la maligna, el carcinoma papilar. Con alto valor de especificidad (97,7%) y valor predictivo positivo (95,4%), la biopsia de aspiracion por aguja fina de tiroides continua siendo el examen auxiliar mas importante en el estudio del paciente con patologia tumoral tiroidea.