cssi/SciSciGPT-SciSciNet huggingface dataset:
Role of endoscopy in gallstone pancreatitis

Early identification of those patients presenting with acute pancreatitis due to gallstone disease is important since emergency intervention may prevent the development of local and systemic complications. Urgent biliary surgery carries unacceptably high morbidity and mortality rates, but endoscopic retrograde cholangiopancreatography in experienced centers appears to be safe and is the optimal method for the diagnosis of bile duct stones. Two randomized controlled prospective trials have shown an advantage for endoscopic sphincterotomy and bile duct clearance compared with supportive therapy when performed within 24 to 72 hours of admission in those patients whose symptoms are considered severe according to prognostic scoring systems.
Detection of functional groups and antibodies on microfabricated surfaces by confocal microscopy.

Fluorescence confocal microscopy was used to characterize micron-sized microfabricated silicon particles and planar oxide surfaces after silanization and immobilization of IgG antibody. Surfaces treated with amino- and mercaptosilanes were tested for the presence of amine and sulfhydryl groups by labeling with specific fluorescein probes. In addition, human antibody (IgG) was immobilized to the thiol-coated microparticles using the heterobifunctional crosslinker succinimidyl 4-(N-maleimidolmethyl)-cyclohexane-1-carboxylate. Estimates of the surface density of IgG were consistent with 8.3% of a monolayer of covalently-bound antibody. Confocal images confirmed uniform layers of both silanes and antibodies on the microparticles. The sensitivity limit for the confocal measurements was determined to be as low as 1.5 x 10 -5 fluors per nm 2 . © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 60: 137-146, 1998.
Predictors of early recurrence of benign esophageal strictures

Abstract Objective In the era of liberal proton pump inhibitor (PPI) use, benign esophageal strictures remain a significant management problem, with 30–40% of patients experiencing symptomatic recurrence within 1 yr of successful dilation. We therefore sought to examine predictors of early recurrence of benign esophageal strictures after endoscopic dilation. Methods Predictors for stricture recurrence were examined in 87 consecutive outpatients undergoing initial dilation over a 1-yr period. Patients with symptomatic recurrence of dysphagia requiring repeat dilation within 1 yr of initial successful dilation (cases) were compared to patients who did not require redilation (controls). Predictors were assessed by univariate and multivariate analysis. Kaplan-Meier analysis of significant predictors using time to first redilation was also performed. Results Of the patients, 36 required repeat dilation within 1 yr, whereas 51 did not (median follow-up, 33 months). Of all strictures, 67 (77%) were peptic, with the remainder caused by radiation, drug-related injury, or congenital stenosis, among other causes. In multivariate analysis, nonpeptic strictures were significant predictors for early recurrence, as was a narrower stricture diameter. For peptic strictures, the persistence of heartburn after dilation and the presence of a hiatal hernia were significant predictors. Of all peptic strictures, 84% of patients were on PPIs after dilation, with no difference between cases and controls. Of all patients with persistent heartburn after dilation, 90% were on PPIs. Conclusions The persistence of heartburn after dilation is a strong predictor for early symptomatic recurrence of benign esophageal peptic strictures, despite a high rate of PPI use. This may suggest persistent acid reflux requiring optimization of acid reduction therapy. Alternatively, combined acid and alkaline reflux may account for progressive injury despite PPI therapy. Esophageal pH studies may be invaluable in making the distinction between acid and non-acidic (alkaline) reflux. Nonpeptic strictures are also more likely to have early recurrences and are therefore more difficult to manage.
Discipline, Accountability, and Legislative Voting in Latin America

What information do citizens have about what goes on inside legislatures, and what difference does it make to the sort of representation provided? These questions are increasingly important as students of comparative politics evaluate the performance of institutions established in new, or renewed, democracies during the last decades of the twentieth century. In Latin America, where the capacity of the legislative branch relative to the executive is of perennial concern to political reformers and academics alike, there is substantial interest in the relationships among parties, legislators, the executive, and citizens. This article examines the internal dynamics of parties across a number of Latin American legislatures, assessing the responsiveness of legislators to competing pressures from party leaders and other actors. Latin America illustrates the frequent tension between partisan and individual accountability among legislators, but this tension is manifest to varying degrees within legislatures generally. By accountability, I mean that representatives communicate to voters what they will do if elected, that information about actions once in office is available to constituents, that representatives are responsive to the preferences and demands of constituents, and that they are punished for lack of responsiveness. In a recent landmark study, Stokes articulates a related notion of accountability of executives and parties as the embodiments of national government but focuses mainly on the first and last elements of my definition, campaign promises and electoral punishment.1 My conception of accountability encompasses transparency and responsiveness as well, in order to direct attention to the perspective of legislators, who are often subject to competing demands from national parties and more narrow electoral constituencies and whose individual roles in the policymaking process are often obscured from public scrutiny. Changes on both these fronts, in representatives' ties to constituencies and in the information about legislators' actions, increase the premium on individual accountability among representatives. Recent institutional reforms in many Latin American countries have altered the balance of resources that induce party discipline. Drawing on interview data with party leaders, legislators, and staff, surveys of legislators, and records of debates and votes, I illustrate how political elites regard these reforms, outline the strain they perceive between loyalty to party and responsiveness to constituents, and discuss the connection between these matters and the normative concept of democratic account-
Structure−Activity Relationship Studies of Ethyl 2-Amino-6-bromo-4-(1-cyano-2-ethoxy-2-oxoethyl)-4H-chromene-3-carboxylate (HA 14-1), an Antagonist for Antiapoptotic Bcl-2 Proteins To Overcome Drug Resistance in Cancer

The structure-activity relationship studies of ethyl 2-amino-6-cyclopentyl-4-(1-cyano-2-ethoxy-2-oxoethyl)-4H-chromene-3-carboxylate (1, HA 14-1), an antagonist of the antiapoptotic Bcl-2 proteins, are reported. A series of analogues of 1 with varied functional groups at the 6-position of the chromene ring were synthesized. These candidates were evaluated for their binding interactions with three antiapoptotic proteins: Bcl-2, Bcl-XL, and Bcl-w. They were also assayed for their in vitro cytotoxicities against a set of Jurkat cells with varied levels of Bcl-2 and Bcl-XL proteins and a non-small-cell lung carcinoma cell line (NCI-H460). It was found that the 6-bromo of 1 was not essential for its bioactivity and the 6-position can accommodate a variety of alkyl groups. 1 and its analogues bind to all of the three antiapoptotic Bcl-2 proteins tested. Positive correlations were observed between the binding affinities of these candidates to the antiapoptotic Bcl-2 proteins and their in vitro cytotoxicities, suggesting that the antiapoptotic Bcl-2 proteins are likely to be the cellular targets of 1 and its analogues. (In this study, the binding interactions of the small molecules to antiapoptotic Bcl-2 proteins were studied by assaying their abilities to compete against a Bak peptide binding to the antiapoptotic Bcl-2 proteins. Inhibitory constants, instead of dissociation constants, were obtained in such assays. The term "binding affinity" is used in this article for simplicity.) The most active compound, 3g, had a >3-fold increase of binding affinity to the antiapoptotic Bcl-2 proteins and a >13-fold increase of in vitro cytotoxicity over 1. Though Jurkat cells with transgenic overexpression of Bcl-2 or Bcl-XL protein can develop resistance to standard cancer therapies, such cells failed to develop resistance to 1 based candidates. 1 also sensitizes Jurkat cells to cisplatin. These studies provide further support that 1 and its analogues function as antagonists for antiapoptotic Bcl-2 proteins and that they have the potential, either as a single agent or as a combination therapy with other anticancer agents, to treat cancers with the overexpression of antiapoptotic Bcl-2 proteins.
Observation of quantized motion of Rb atoms in an optical field.

We observe transitions of laser-cooled Rb between vibrational levels in subwavelength-sized optical potential wells, using high-resolution spectroscopy of resonance fluorescence. We measure the spacing of the levels and the population distribution, and find the atoms to be localized to 1/15 of the optical wavelength. We find up to 60% of the population of trapped atoms in the vibrational ground state. The dependence of the spectrum on the parameters of the optical field provides detailed information about the dynamics of laser-cooled atoms.
RESPONSE TO COMMENT ON "How the Horned Lizard Got Its Horns"

Agosta and Dunham ([ 1 ][1]) argue that our study ([ 2 ][2]) did not consider the phylogenetic definition of adaptation and therefore cannot reveal the origin of horns in the larger group of horned lizards. Because we neither presented phylogenetic evidence nor made claims about the historical
The Routledge History of Social Protest in Popular Music

I was very excited when I first received Jonathan C. Friedman’s Routledge History of Social Protest in Popular Music. The collection of 28 essays is designed to “analyze the trends, musical formats...
Pharmacokinetics and tissue distribution of inositol hexaphosphate in C.B17 SCID mice bearing human breast cancer xenografts

Inositol hexaphosphate (IP(6)) is effective in preclinical cancer prevention and chemotherapy. In addition to cancer, IP(6) has many other beneficial effects for human health, such as reduction in risk of developing cardiovascular disease and diabetes and inhibition of kidney stone formation. Studies presented here describe the pharmacokinetics, tissue distribution, and metabolism of IP(6) following intravenous (IV) or per os (PO) administration to mice. SCID mice bearing MDA-MB-231 xenografts were treated with 20 mg/kg IP(6) (3 μCi per mouse [(14)C]-uniformly ring-labeled IP(6)) and euthanized at various times after IP(6) treatment. Plasma and tissues were analyzed for [(14)C]-IP(6) and metabolites by high-performance liquid chromatography with radioactivity detection. Following IV administration of IP(6), plasma IP(6) concentrations peaked at 5 minutes and were detectable until 45 minutes. Liver IP(6) concentrations were more than 10-fold higher than plasma concentrations, whereas other normal tissue concentrations were similar to plasma. Only inositol was detected in xenografts. After PO administration, IP(6) was detected in liver; but only inositol was detectable in other tissues. After both IV and PO administration, exogenous IP(6) was rapidly dephosphorylated to inositol; however, alterations in endogenous IPs were not examined.
Predictive Utility of Brief Alcohol Use Disorders Identification Test (AUDIT) for Human Immunodeficiency Virus Antiretroviral Medication Nonadherence

Alcohol use negatively affects adherence to antiretroviral therapy (ART), thus human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) care providers need accurate, efficient assessments of alcohol use. Using existing data from an efficacy trial of 2 cognitive-behavioral ART adherence interventions, the authors sought to determine if results on 2 common alcohol screening tests (Alcohol Use Disorders Identification Test--Consumption [AUDIT-C] and its binge-related question [AUDIT-3]) predict ART nonadherence. Twenty-seven percent of the sample (n = 308) were positive on the AUDIT-C and 34% were positive on the AUDIT-3. In multivariate analyses, AUDIT-C-positive status predicted ART nonadherence after controlling for race, age, conscientiousness, and self-efficacy (P = .036). Although AUDIT-3-positive status was associated with ART nonadherence in unadjusted analyses, this relationship was not maintained in the final multivariate model. The AUDIT-C shows potential as an indirect screening tool for both at-risk drinking and ART nonadherence, underscoring the relationship between alcohol and chronic disease management.
Recent developments in VUV femtosecond pulse generation: proposal for a higher efficiency F2 (157-nm) laser

The efficiency of the four-wave mixing (2 (omega) 1 - (omega) 2), VUV femtosecond source described by us last year (SPIE Vol. 1861) inherently relies upon a two-photon resonance enhancement occurring (in Xe gas) when (lambda) 1 approximately equals 248.5 nm. However, it also depends upon the spatial and temporal coherence properties of the input pulses. Development of a new source for producing beams at (omega) 1 with greatly improved coherence properties is reported here. Performance of the four-wave mixing source with these (omega) 1 pulses is described. Femtosecond VUV pulses with energies as high as approximately 60 (mu) J are generated. As a separate topic, we propose the use of a pulsed (nanosecond) infrared laser to deplete the terminal state of an F2 (157-nm) laser in order to greatly enhance its performance.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
All stability multipliers for repeated MIMO nonlinearities

For block structured monotone or incrementally positive n-dimensional nonlinearities, the largest class of convolution operators (stability multipliers) that preserve positivity is derived. These multipliers can be used in conjunction with positivity and IQC stability criteria to evaluate stability and robustness of MIMO feedback systems.
CETP polymorphisms associated with HDL cholesterol may differ from those associated with cardiovascular disease.

Abstract To better understand the role of cholesteryl ester transfer protein (CETP) in cardiovascular disease, nine polymorphisms spanning the gene from the upstream promoter region to beyond the 3′UTR were genotyped in 2553 individuals from multiple ethnic groups and with different cardiovascular disease profiles. The frequency of four of these SNPs varied by 40–300% between Caucasians and African Americans. SNPs in each ethnic group fell into two haploblocks with significant linkage disequilibrium within each block. SNPs in the 5′ haploblock were significantly associated with HDL cholesterol while SNPs in the 3′ haploblock were, at best, only weakly associated with HDL-C. One SNP in the 3′ haploblock (rs1800774 in intron 12) was highly associated with history of myocardial infarction even though it was not associated with HDL-C. This association was driven by the effect in Caucasian women where 11.9% of the women with no history of MI are homozygous for the less common allele while 23.7% of those with a history of MI share this genotype. In addition, this SNP was highly associated with BMI among Caucasians ( p
Gas resources and gas markets: a global view

Abstract Although natural gas constitutes 42% of the energy content of world hydrocarbon resources, it accounts for only about 8% of total international oil and gas trade. Gas-trade projects are costly and require large scale “anchors” at each end: a substantial market in the importing region and a significant gas reserve in the exporting country. Due to the small size of many gas deposits, and for other reasons, many of the world's gas reserves are not well-suited as a basis for international trade. They will be used increasingly to support local economic development or will remain in the ground until markets emerge. Gas reserves may be classified according to their degree of accessibility to local and international markets. Countries facing gas-development decisions must consider such questions as how best to encourage gas exploration, what volume of gas to set aside for future domestic consumption and, if reserves are sufficient to justify an export project, how to determine the value of gas in the markets of importing countries.
Targeting the insulin growth factor receptor 1

The IGF axis is a tightly controlled endocrine system that regulates cell growth and development, known to have an important function in cancer biology. IGF1 and IGF2 can promote cancer growth in a GH-independent manner both through paracrine and autocrine secretion and can also confer resistance to chemotherapy and radiation. Many alterations of this system have been found in neoplasias, including increased expression of ligands and receptors, loss of heterozygosity of the IGF2 locus and increased IGF1R gene copy number. The IGF1 network is an attractive candidate for targeted therapy, including receptor blockade with monoclonal antibodies and small molecule inhibitors of receptor downstream signaling. This article reviews the role of the IGF axis in the initiation and progression of cancer, and describes the recent advances in IGF inhibition as a therapeutic tool.
A Technoeconomic Analysis of the Potential for Portable Pyrolysis in Northern New Mexico Forests

Biomass pyrolysis systems can be designed to yield significant quantities of liquid. The liquids have approximately half the heating value of transportation fuels, depending strongly on the water content in the liquids. They are acidic, and tend to change with time, becoming more viscous and higher in molecular weight. However the process required to generate them is simple, and they hold promise to be a renewable source of liquid fuel if they can be produced in a way that is cost-effective. Northern New Mexico forests are mostly characterized by small diameter (less than or equal to 10 cm) conifer trees. For mitigation of fire risk, land owners are required to periodically thin their lands. This generates significant waste product with little or no commercial value. The most widely used current practice is to accumulate and burn the cut wood, or to leave it to rot. Seeking a more effective and ecologically friendly use of the waste, a scaled experimental pyrolysis system was developed using design principles focused on the portable model. The data from this test unit and historical data are used to evaluate the break-even costs of performing pyrolysis. The char co-product is found to have a slight beneficial effect on the economics of the analysis. Labor is a significant fraction of the cost. Economies of scale are important, so the largest system that can be transported will make the most economic sense. On a price per unit energy, this model may be competitive with liquid transportation fuels and fuel oil. However pyrolysis oils will have difficulty competing with natural gas at current regional prices. Other regions may show a more positive comparison, especially in parts of the world where labor is much less expensive.Copyright © 2012 by ASME
Evaluating the accuracy of theoretical transition data

As theory produces more and more transition probabilities for which experimental values are not available, an independent assessment of accuracy is needed. Factors affecting accuracy of theoretical results are discussed. It is shown how the accuracy of the transition energy and the discrepancy in the length and velocity form of the line strength, in a general way, can determine which of two ab initio sets of results are the more accurate. Some methods of estimating absolute accuracy are proposed and compared with the online Atomic Spectra Database assessments.
Endocrinological screening of embryo donors and embryo transfer recipients: A review of research with cattle

Abstract Fertility of cattle inseminated at a natural estrus is related to the endocrine profile before and after insemination. Highest fertility is associated with: 1) high concentrations of progesterone (P) during the luteal phase of the estrous cycle preceding insemination, 2) precipitous, rather than gradual, decline in P during luteolysis, 3) close synchrony between the onset of estrus and the preovulatory surge of luteinizing hormone (LH), 4) low but detectable levels of P from 2 d before until 3 to 4 d after onset of estrus, and 5) a robust increase in P during the subsequent luteal phase when the corpus luteum is becoming fully functional. In superovulated donors, the number of transferrable embryos is: 1) related negatively to stimulation of P secretion by the treatment for induction of superovulation, 2) greater when the surge of LH occurs at the onset of estrus and when the LH surge is of a greater magnitude and longer duration, 3) related negatively to elevated levels of P during and for 2 to 3 d after estrus, and 4) related positively with the concentration of P during days 3 to 7 after estrus. In embryo transfer recipients, survival of embryos is higest when concentrations of P on the day of transfer are moderate. Blood samples must be collected several times daily for accurate determination of LH, follicle stimulating hormone (FSH) and estradiol (E), because the peaks of these hormones near estrus are short-lived. Progesterone and E can be measured in milk and the levels in milk reflect the average level in blood between milkings. Measurement of P in milk or blood is useful for reducing errors in detection of estrus of both donors and recipients and for eliminating potential donors that are not at the correct stage of an estrous cycle for superovulation. The absolute tolerance levels for acceptable or unacceptable levels of hormones in blood vary depending on assay procedures and how samples are handled.
Designing Species Translocation Strategies When Population Growth and Future Funding Are Uncertain

When translocating individuals to found new populations, managers must allocate limited funds among release and monitoring activities that differ in method, cost, and probable result. In addition, managers are increasingly expected to justify the funding decisions they have made. Within the framework of decision analysis, we used robust optimization to formulate and solve different translocation problems in which both population growth and future funding were uncertain. Performance criteria included maximizing mean population size and minimizing the risk of undesirable population-size outcomes. Robust optimization provided several insights into the design of translocation strategies: (1) risk reduction is obtained at the expense of mean population size; (2) as survival of released animals becomes more important, funds should be allocated to release methods with lower risks of failure, regardless of costs; (3) the performance gain from monitoring drops as the proportion of a fixed budget required to pay for monitoring increases; and (4) as the likelihood of obtaining future funding increases, more of the existing budget should be spent on building release capacity rather than saved for future operating costs. These relationships highlight the importance of performance criteria and economic costs in determining optimal release and monitoring strategies.
Prone positioning for ARDS: defining the target.

Although variation of position is innate to healthy subjects, practitioners usually orient critically ill patients in a supine, semirecumbent posture for days to weeks, with only periodic, side-to-side repositioning through a relatively shallow 30–60° arc. Experimental data [1] and clinical observations [2–4] demonstrate physiologic benefit from prone positioning during acute lung injury (ALI), but recent large clinical trials have been unable to confirm survival benefit in diverse populations of patients labeled as having ALI/acute respiratory distress syndrome (ARDS) [5–7]. However, posttrial subgroup analyses hint that certain patient subgroups may indeed benefit from prone orientation. Severely ill patients, those experiencing improved CO2 exchange, and those ventilated with large tidal volumes appear more likely to benefit than other members of the general cohort [5]. A superb meta-analysis of pooled data appears in this issue, focusing on those relative few with the worst oxygen exchange [8]. This analysis shows convincingly that, while proning cannot be recommended for all patients with acute lung injury, it does hold therapeutic value for some.
Environmental lead exposure and urate excretion in the general population.

Abstract Purpose Chronic occupational exposure to lead is related to low urate excretion and a high incidence of gout in lead workers. However, whether chronic low-level environmental lead exposure influences urate excretion in the general population remains unknown. Subjects and methods We studied 111 healthy subjects with normal renal function (serum creatinine level ≤1.4 mg/dL) and no previous lead exposure or systemic diseases. All subjects had their blood lead levels measured, received ethylenediaminetetraacetic acid mobilization tests to assess their body lead burdens, and were investigated for renal function and urate excretion to assess the relation between lead and urate excretion. We studied urate excretion before and after lead chelation therapy in 24 subjects with high-normal body lead burden (>78 mg and Results Healthy subjects with gout (n = 27) manifested a higher body lead burden (84 ± 42 mg vs. 45 ± 30 mg, P 2 vs. 6.0 ± 2.8 mL/min/1.73 m 2 , P P = 0.03), and body lead burdens were related to all indices of urate excretion (serum urate: β coefficient=0.023 ± 0.005, P P = 0.0002; urate clearance: β coefficient=−0.030 ± 0.006, P P 2 vs. 4.9 ± 1.4 mL/min/1.73 m 2 , P Conclusion Chronic low-level environmental lead exposure may inhibit urate excretion in the general population, and lead chelation therapy reduces this inhibition. These findings support efforts to reduce sources of environmental lead exposure and suggest alternative approaches to hyperuricemia and gout in the general population.
Distinct and Opposite Activities of Human Terminal Deoxynucleotidyltransferase Splice Variants

Evidence for potential human TdT (hTdT) isoforms derived from hTdT genomic sequences led us to identify the short isoform (hTdTS), as well as mature long transcripts containing exon XII (hTdTL1) and another including exon VII (hTdTL2) in lymphoid cells. Normal B and T lymphocytes express exclusively hTdTS and hTdTL2, whereas hTdTL1 expression appears to be restricted to transformed lymphoid cell lines. In in vitro recombination and primer assays, both long isoforms were shown to have 3'-->5' exonuclease activity. Overexpression of hTdTS or hTdTL2 greatly reduced the efficiency of recombination, which was reverted to normal levels by the simultaneous expression of both enzymes. Therefore, alternative splicing may prevent the adverse effects of unchecked elongation or diminution of coding ends during V(D)J recombination, thus affecting the survival of a B or T cell precursor during receptor gene rearrangements. Finally, the newly discovered hTdT isoforms should be considered in future screening of human leukemias.
Ovine smoke/burn ARDS model: a new ventilator-controlled smoke delivery system.

Background Our current ovine smoke/burn acute respiratory distress syndrome (ARDS) model utilizes a manual bee smoker. This smoke delivery system lacks standardization and reproducibility, with 20% of sheep failing to meet ARDS criteria. Time to reach ARDS criteria and survival time are also variable. The mild volutrauma (15 mL/kg) applied after smoke/burn injury may also fail to induce ARDS within 24 h. We hypothesized that these inconsistencies were associated with the bee smoker and the mild volutrauma. In the current study, we addressed these problems to improve the consistency of the smoke/burn ARDS model. Methods Adult female sheep (n = 10) were given a 40% total body surface area third degree cutaneous burn and 48 breaths (4 × 12) of cotton smoke under general anesthesia. A modified ventilator was then used to deliver a precise and consistent smoke volume (tidal volume) to the sheep. Additional barotrauma was induced by pressure control ventilation (40 cm H20). When ARDS criteria (PaO2/FiO2 < 200) were met, the ARDS Network low tidal volume ventilation protocol (6–8 mL/kg ideal body weight) was used. Results Carboxyhemoglobin levels were 81.4% ± 5.6% immediately following smoke injury. All sheep met ARDS criteria within 24 h (12.5 ± 4.9 h). Mean survival time post-injury was 62.1 ± 26.4 h. White blood cells and granulocytes were significantly elevated at 24 h post-smoke/burn injury. Lung tissue at necropsy was consistent with ARDS. Conclusions The refinements made to the original ovine smoke/burn ARDS model produce a more reliable time to ARDS onset, injury severity, and time of death.
Intrinsic physiology of identified neurons in the prepositus hypoglossi and medial vestibular nuclei.

Signal processing in the vestibular system is influenced by the intrinsic physiological properties of neurons that differ in neurotransmitters and circuit connections. Do membrane and firing properties differ across functionally distinct cell types? This study examines the intrinsic physiology of neurons in the medial vestibular nucleus (MVN) and nucleus prepositus hypoglossi (NPH) which express different neurotransmitters and have distinct axonal projections. NPH neurons expressing fluorescent proteins in glutamatergic, glycinergic, or GABAergic neurons were targeted for whole cell patch recordings in brainstem slices obtained from transgenic mouse lines (YFP-16, GlyT2, and GIN). Recordings from MVN neurons projecting to the spinal cord, reticular formation, or oculomotor nucleus were obtained by targeting fluorescent neurons retrogradely labeled from tracer injections. Intrinsic physiological properties of identified neurons exhibited continuous variations but tended to differ between functionally defined cell types. Within the NPH, YFP-16 neurons had the narrowest action potentials and highest evoked firing rates and expressed high levels of Kv3.3 proteins, which speed repolarization. MVN neurons projecting to the spinal cord and oculomotor nucleus had similar action potential waveforms, but oculomotor-projecting neurons had higher intrinsic gains than those projecting to the spinal cord. These results indicate that intrinsic membrane properties are differentially tuned in MVN and NPH neurons subserving different functions.
Communications to the Editor---Competitive Bidding with Disparate Information

This paper analyses competitive bidding via sealed tenders for the case in which the bidders have different sources and amounts of information available about the value of the prize. The equilibrium pure strategies are characterized and computational methods are derived. A simple example is solved completely.
Core RNA Polymerase from E. coli Induces a Major Change in the Domain Arrangement of the σ70 Subunit

Luminescence resonance energy transfer measurements were used to show that binding of E. coli core RNA polymerase induced major changes in interdomain distances in the sigma 70 subunit. The simplest model describing core-induced changes in sigma 70 involves a movement of the conserved region 1 by approximately 20 A and the conserved region 4.2 by approximately 15 A with respect to conserved region 2. The core-induced movement of region 1 (autoinhibition domain) and region 4.2 (DNA-binding domain) provides structural rationale for allosteric regulation of sigma 70 DNA binding properties by the core and suggests that this regulation may not only involve directly the autoinhibition domain of sigma 70 but also could involve a modulation of spacing between DNA-binding domains of sigma 70 induced by binding of core RNAP.
Flexible Dermal Armor in Nature

Many animals possess dermal armor, which acts primarily as protection against predators. We illustrate this through examples from both our research and the literature: alligator, fish (alligator gar, arapaima, and Senegal bichir), armadillo, leatherback turtle, and a lizard, the Gila monster. The dermal armor in these animals is flexible and has a hierarchical structure with collagen fibers joining mineralized units (scales, tiles, or plates). This combination significantly increases the strength and flexibility in comparison with a simple monolithic mineral composite or rigid dermal armor. This dermal armor is being studied for future bioinspired armor applications providing increased mobility.
The Cardiovascular Pharmacology of COX-2 Inhibition

Selective inhibitors of cyclooxygenase (COX)-2, the coxibs, were developed to inhibit inflammatory prostaglandins derived from COX-2, while sparing gastroprotective prostaglandins primarily formed by COX-1. However, COX-2-derived prostaglandins mediate not only pain and inflammation but also affect vascular function, the regulation of hemostasis/ thrombosis, and blood pressure control. All coxibs depress COX-2-dependent prostacyclin (PGI(2)) biosynthesis without effective suppression of platelet COX-1-derived thromboxane (Tx) A(2), unlike aspirin or traditional nonsteroidal anti-inflammatory drugs, which inhibit both COX-1 and COX-2. The actions of PGI(2) oppose mediators, which stimulate platelets, elevate blood pressure, and accelerate atherogenesis, including TxA(2). Indeed, structurally distinct inhibitors of COX-2 have increased the likelihood of hypertension, myocardial infarction and stroke in controlled clinical trials. The detection of these events in patients is related to the duration of exposure and to their baseline risk of cardiovascular disease. Thus, coxibs should be withheld from patients with preexisting cardiovascular risk factors, and exposed patients at low cardiovascular baseline risk should be monitored for changes in their risk factor profile, such as increases in arterial blood pressure.
Lys6-modified ubiquitin inhibits ubiquitin-dependent protein degradation.

Ubiquitin plays essential roles in various cellular processes; therefore, it is of keen interest to study the structure-function relationship of ubiquitin itself. We investigated the modification of Lys6 of ubiquitin and its physiological consequences. Mass spectrometry-based peptide mapping and N-terminal sequencing demonstrated that, of the 7 Lys residues in ubiquitin, Lys6 was the most readily labeled with sulfosuccinimidobiotin. Lys6-biotinylated ubiquitin was incorporated into high molecular mass ubiquitin conjugates as efficiently as unmodified ubiquitin. However, Lys6-biotinylated ubiquitin inhibited ubiquitin-dependent proteolysis, as conjugates formed with Lys6-biotinylated ubiquitin were resistant to proteasomal degradation. Ubiquitins with a mutation of Lys6 had similar phenotypes as Lys6-biotinylated ubiquitin. Lys6 mutant ubiquitins (K6A, K6R, and K6W) also inhibited ATP-dependent proteolysis and caused accumulation of ubiquitin conjugates. Conjugates formed with K6W mutant ubiquitin were also resistant to proteasomal degradation. The dominant-negative effect of Lys6-modified ubiquitin was further demonstrated in intact cells. Overexpression of K6W mutant ubiquitin resulted in accumulation of intracellular ubiquitin conjugates, stabilization of typical substrates for ubiquitin-dependent proteolysis, and enhanced susceptibility to oxidative stress. Taken together, these results show that Lys6-modified ubiquitin is a potent and specific inhibitor of ubiquitin-mediated protein degradation.
Assessment of systemic corticosteroid activity

The potency of the inhaled corticosteroid, dose, duration of treatment, and the study subject receiving treatment all play a role in the effects observed on the HPA axis. At low/medium doses of inhaled corticosteroids, where there is minimal/modest HPA axis suppression, there should be no risk of adrenal crisis even under stressful conditions (6). Thus, the risk of acute adrenal insufficiency, culminating in adrenal crisis, in patients taking inhaled steroids is extremely unlikely.
Constraints on braneworld gravity models from a kinematic limit on the age of the black hole XTE J1118 + 480

In braneworld gravity models with a finite anti-de Sitter space (AdS) curvature in the extra dimension, the AdS/conformal field theory correspondence leads to a prediction for the lifetime of astrophysical black holes that is significantly smaller than the Hubble time, for asymptotic curvatures that are consistent with current experiments. Using the recent measurements of the position, three-dimensional spatial velocity, and mass of the black hole XTE J1118+480, I calculate a lower limit on its kinematic age of > or =11 Myr (95% confidence). This translates into an upper limit for the asymptotic AdS curvature in the extra dimensions of <0.08 mm, which significantly improves the limit obtained by table top experiments of sub mm gravity.
Seven years of carbon dioxide enrichment, nitrogen fertilization and plant diversity influence arbuscular mycorrhizal fungi in a grassland ecosystem.

Summary • We tested the prediction that the abundance and diversity of arbuscular mycorrhizal (AM) fungi are influenced by resource availability and plant community composition by examining the joint effects of carbon dioxide (CO2) enrichment, nitrogen (N) fertilization and plant diversity on AM fungi. • We quantified AM fungal spores and extramatrical hyphae in 176 plots after 7 yr of treatment with all combinations of ambient or elevated CO2 (368 or 560 ppm), with or without N fertilization (0 or 4 g N m )2 ), and one (monoculture) or 16 host plant species (polyculture) in the BioCON field experiment at Cedar Creek Ecosystem Science Reserve, Minnesota, USA. • Extramatrical hyphal lengths were increased by CO2 enrichment, whereas AM spore abundance decreased with N fertilization. Spore abundance, morphotype richness and extramatrical hyphal lengths were all greater in monoculture plots. A structural equation model showed AM fungal biovolume was most influenced by CO2 enrichment, plant community composition and plant richness, whereas spore richness was most influenced by fungal biovolume, plant community composition and plant richness. • Arbuscular mycorrhizal fungi responded to differences in host community and resource availability, suggesting that mycorrhizal functions, such as carbon sequestration and soil stability, will be affected by global change.
How Host Population Dynamics Translate into Time-Lagged Prevalence: An Investigation of Sin Nombre Virus in Deer Mice

Human cases of hantavirus pulmonary syndrome caused by Sin Nombre virus are the endpoint of complex ecological cascade from weather conditions, population dynamics of deer mice, to prevalence of SNV in deer mice. Using population trajectories from the literature and mathematical modeling, we analyze the time lag between deer mouse population peaks and peaks in SNV antibody prevalence in deer mice. Because the virus is not transmitted vertically, rapid population growth can lead initially to reduced prevalence, but the resulting higher population size may later increase contact rates and generate increased prevalence. Incorporating these factors, the predicted time lag ranges from 0 to 18 months, and takes on larger values when host population size varies with a longer period or higher amplitude, when mean prevalence is low and when transmission is frequency-dependent. Population size variation due to variation in birth rates rather than death rates also increases the lag. Predicting future human outbreaks of hantavirus pulmonary syndrome may require taking these effects into account.
BARIUM AND NEODYMIUM ISOTOPIC ANOMALIES IN THE ALLENDE METEORITE

Isotopic anomalies have been found for Ba and N d in two inclusions from the Allende meteorite. These inclusions are typical Ca-Al-rich objects associated with early condensates from the solar nebula but have distinctive 0 and Mg isotopic anomalies of the FUN type. Sample C1 shows a depletion only in ^(135)Ba of 2 parts in 10^4 and normal Nd. Sample EK1-4-1 shows large positive excesses in the unshielded isotopes ^(135)Ba and ^(137)Ba of 13.4 and 12.3 parts in 10^4, respectively. The Nd isotopic composition in EK1-4-1 is highly aberrant in at least five isotopes. Both the Ba and Nd anomalies can be explained by a model of r-process addition. These anomalies are found to be uniform between coexisting mineral phases. These observations show the existence of substantial isotopic anomalies in refractory elements in the neighborhood of Xe and extend the range of elements showing isotopic effects to 0, Ne, Mg, Ca, Kr, Xe, Ba, and Nd. The observations, in conjunction with the presence of ^(26)Al (r_(1/2) = 7 X 10^5 years), are interpreted as the result of a nearby supernova explosion which produced elements over a wide mass range and injected them into the early solar nebula shortly before condensation.
Luminescent solar concentrators: effects of shape on efficiency.

The effects of shape and photovoltaic cell placement on efficiency are studied for luminescent solar concentrators. The mean path length of light rays is found to be a poor measure of performance. Simple arguments based on a method of images show that the efficiency grows linearly with detector size h, saturating at h ≈ πA/λ, where A is the captation area of the collector, and λ is the attenuation length of radiation in the medium. Monte Carlo simulations confirm that efficiency is relatively independent of collector geometry.
Local Density in Graphs with Forbidden Subgraphs

A celebrated theorem of Turan asserts that every graph on n vertices with more than $\frac{r\,{-}\,1}{2r}n^2$ edges contains a copy of a complete graph $K_r+1$. In this paper we consider the following more general question. Let G be a $K_r+1-free graph of order n and let α be a constant, 0<α≤1. How dense can every induced subgraph of G on αn vertices be? We prove the following local density extension of Turan's theorem.For every integer $r\geq 2$ there exists a constant $c_r < 1$ such that, if $c_r < \alpha < 1$ and every αn vertices of G span more than\[ \frac{r\,{-}\,1}{2r}(2\alpha -1)n^2\vspace*{7pt} \]edges, then G contains a copy of $K_r+1$. This result is clearly best possible and answers a question of Erdos, Faudree, Rousseau and Schelp [5].In addition, we prove that the only $K_r+1-free graph of order n, in which every αn vertices span at least $\frac{r\,{-}\,1}{2r}(2\alpha -1)n^2$ edges, is a Turan graph. We also obtain the local density version of the Erdos–Stone theorem.
Mechanics of Pipes Conveying Fluids—Part II: Applications and Fluidelastic Problems

This paper is the second part of the two-part review article presenting an overview of mechanics of pipes conveying fluid and related problems such as the fluid-elastic instability under conditions of turbulence in nuclear power plants. In the first part, different types of modeling, dynamic analysis and stability regimes of pipes conveying fluid restrained by elastic or inelastic barriers were described. The dynamic and stability behaviors of pinnedpinned, clamped-clamped, and cantilevered pipes conveying fluid together with curved and articulated pipes were discussed. Other problems such as pipes made of viscoelastic materials and active control of severe pipe vibrations were considered. The first part was closed by conclusions highlighting resolved and nonresolved controversies reported in the literature. The second part will address the problem of fluidelastic instability in single- and twophase flows and fretting wear in process equipment, such as heat exchangers and steam generators. Connors critical velocity will be discussed as a measure of initiating fluidelastic instability. Vibro-impact of heat exchanger tubes and the random excitation by the cross-flow can produce a progressive damage at the supports through fretting wear or fatigue. Antivibration bar supports used to limit pipe vibrations are described. An assessment of analytical, numerical, and experimental techniques of fretting-wear problem of pipes in heat exchangers will be given. Other topics related to this part include remote impact analysis and parameter identification, pipe damage-induced by pressure elastic waves, the dynamic response and stability of long pipes, marine risers together with pipes aspirating fluid, and carbon nanotubes conveying fluid. DOI: 10.1115/1.4001270
The muscular network of the sheep right atrium and frequency‐dependent breakdown of wave propagation

The complex branching structure of the right atrium (RA) muscular network may provide the substrate for complex patterns of propagation during atrial fibrillation (AF). As AF results in some cases from stable sources in the left atrium (LA) with fibrillatory conduction toward the RA, we hypothesize that periodic input to the RA at an exceedingly high frequency results in disorganized wave propagation associated with the complex structure of the RA. Optical mapping was performed in isolated coronary-perfused sheep RA. Rhythmic pacing of Bachmann's bundle allowed well-controlled and realistic conditions for LA-driven RA. Pacing at increasingly higher frequencies led to increasing delays in activation distal to major branching sites of the Crista terminalis and pectinate bundles, culminating in spatially distributed intermittent blockade at and above approximately 6.5 Hz. At this breakdown frequency, the dominant frequencies of the RA response activity became spatially nonuniform. Such frequency-dependent changes were independent of action potential duration. Rather, the spatial boundaries between proximal and distal frequencies correlated well with branch sites of the pectinate musculature. Thus, there exists a breakdown frequency in the sheep RA below which activity is periodic throughout the atrium and above which it is fibrillation-like, consistent with the ideas that during AF, high-frequency activation initiated in the LA undergoes fibrillatory conduction toward the RA, and that sink-to-source mismatch effect at branch points of the Crista terminalis and pectinate muscles is important in determining the complexity of the arrhythmia.
Effects of conjugated estrogen on the calcitriol response to parathyroid hormone in postmenopausal women.

We evaluated the effects of estrogen on the calcitriol response to the active peptide, human PTH(1-34), in postmenopausal women. Fifteen women were studied before and again after at least 1 month of treatment with conjugated equine estrogens, 1.25 mg/day. Six women received two series of four graded peptide infusions, each with the sequence 200, 400, 800, and 1600 USP U hPTH(1-34). Nine women received only one dose of peptide, either 200 or 800 U, before and while taking estrogen. Baseline values and the incremental and percent changes in circulating calcitriol 24 h after the 20-min infusions were evaluated. Estrogen treatment resulted in significant reductions in blood levels of calcium (2.26 +/- 0.03 mmol/L vs. 2.16 +/- 0.02, P less than 0.05) and phosphorus (1.23 +/- .05 mmol/L vs. 1.14 +/- 0.03, P less than 0.005), a rise in serum calcitriol concentrations (42.2 +/- 3.9 pg/mL vs. 28.6 +/- 3.1, P less than 0.005), and no change in circulating PTH. The rise in calcitriol after 200 U hPTH(1-34) was signi...
Frequency-domain bit-flipping equalizer for wideband MIMO channels

We propose a low-complexity equalizer whose performance approaches that of the optimal maximum-likelihood estimators in wideband multiple-input multiple-output (MIMO) channels. The proposed algorithm makes use of a bit-flipping refinement procedure preceded by a frequency-domain equalizer and is based on local-optima searching algorithms. Through performance evaluations, it is demonstrated that the proposed equalizer can perform well when a large number of diversity branches are available in severely dispersive fading channels.