cssi/SciSciGPT-SciSciNet huggingface dataset:
Conformation and self-association of the peptide hormone substance P: Fourier-transform infrared spectroscopic study.

Fourier-transform i.r. (f.t.i.r.) spectroscopy has been applied to the study of the conformational properties of substance P in aqueous solution. Spectra were obtained in the presence of lipid membranes and Ca2+ to assess the role of these factors in induction of the active conformation of the peptide. In aqueous solution substance P was found to be predominantly unstructured at physiological p2H, where the lack of long-range order is probably related to charge repulsion along the peptide chain. However, substance P aggregated in aqueous solution at p2H > 10.0. Little or no induction of secondary structure was seen on addition of the peptide to negatively charged bilayers, suggesting that interaction with a membrane surface does not play an important role in the stabilization of the active conformation of the peptide. In fact, substance P was found to aggregate in the presence of charged lipids, which would tend to hinder rather than enhance interaction with the receptor. We propose a model for the aggregation of substance P at the bilayer surface, based on our studies of the effect of p2H and lipid/peptide ratio on spectra. Addition of Ca2+ had no effect upon the secondary structure of the peptide or on its interactions with membranes.
Removal and Recovery of Heavy Metal Ions by Two-dimensional MoS2 Nanosheets: Performance and Mechanisms

We investigated the removal of heavy metals from water by two-dimensional MoS2 nanosheets suspended in aqueous solution, and restacked as thin film membranes, respectively. From these studies we elucidated a new heavy metal ion removal mechanism that involves a reduction–oxidation (redox) reaction between heavy metal ions and MoS2 nanosheets. Ag+ was used as a model species and MoS2 nanosheets were prepared via chemical exfoliation of bulk powder. We found that the Ag+ removal capacity of suspended MoS2 nanosheets was as high as ∼4000 mg/g and adsorption accounted for less than 20% of removal, suggesting the reduction of Ag+ to metallic silver as a dominant removal mechanism. Furthermore, we demonstrated that MoS2 membranes were able to retain a similar high removal capacity, and attribute this capability to the formation of a conductive, permeable multilayer MoS2 structure, which enables a corrosion-type reaction involving electron transfer from a MoS2 site inside the membrane (anode) to another site on ...
Tenofovir Diphosphate in Dried Blood Spots Is Strongly Associated With Viral Suppression in Individuals With Human Immunodeficiency Virus Infections.

BACKGROUND Although tenofovir diphosphate (TFV-DP) in dried blood spots (DBS) is a predictor of adherence and pre-exposure prophylaxis efficacy, its utility in human immunodeficiency virus (HIV) treatment remains unknown. METHODS DBS for TFV-DP were collected up to 3 times over 48 weeks in persons living with HIV (PLWH) who were receiving TFV disoproxil fumarate (TDF)-based therapy. Log-transformed baseline TFV-DP was compared using t-tests or analyses of variance; generalized estimating equations were used to estimate the adjusted odds ratio (aOR) of viral suppression (<20 copies/mL) based on the TFV-DP concentration at the study visit. RESULTS We analyzed 1199 DBS from 532 participants (76 female; 101 Black, 101 Hispanic). Among the virologically-suppressed participants at baseline (n = 347), TFV-DP was lower in Blacks (geometric mean 1453, 95% confidence interval [CI] 1291-1635) vs Whites (1793, 95% CI 1678-1916; P = .002) and Hispanics (1760, 95% CI 1563-1982; P = .025); in non-boosted (1610, 95% CI 1505-1723) vs. boosted (1888, 95% CI 1749-2037; P = .002) regimens; and in non-nucleoside reverse transcription inhibitor-based (1563, 95% CI 1432-1707) vs. boosted protease inhibitor-based (1890, 95% CI 1704-2095; P = .006) and multiclass-based (1927, 95% CI 1650-2252; P = .022) regimens. The aOR of virologic suppression, after adjusting for age, gender, race, body mass index, estimated glomerular filtration rate, CD4+ T-cell count, antiretroviral drug class and duration of therapy, was 73.5 (95% CI 25.7-210.5; P < .0001) for a TFV-DP concentration ≥1850 fmol/punch compared to <350 fmol/punch. CONCLUSIONS TFV-DP in DBS is strongly associated with virologic suppression in PLWH on TDF-based therapy and is associated with certain participant characteristics. Further research is required to evaluate this drug adherence and exposure measure in clinical practice. CLINICAL TRIALS REGISTRATION NCT02012621.
Generic chemoprevention of hepatocellular carcinoma

Chronic fibrotic liver disease caused by viral or metabolic etiologies is a high-risk condition for developing hepatocellular carcinoma (HCC). Even after curative treatment of early-stage HCC tumor, the carcinogenic microenvironment persists in the remnant diseased liver and supports the development of de novo HCC tumors (de novo HCC recurrence). Therefore, prevention of HCC development in patients at risk of not only first-primary but also second-primary HCC tumors is theoretically the most impactful strategy to improve patient prognosis. However, no such therapy has been established to date. One major challenge is the identification of clinically relevant targets that can be achieved by utilizing the reverse-engineering strategy of chemoprevention discovery, which integrates omics information from clinical cohorts with completed follow-up for cancer development. Clinical and experimental studies have suggested etiology-specific and generic candidate HCC chemoprevention strategies, including statins, antidiabetic drugs, selective molecular targeted agents, and dietary and nutritional substances. Clinical testing of the candidate compounds can be cost-effectively performed by combining it with HCC risk biomarker evaluation to specify the target patient population most likely to benefit from the therapy. Nontoxic, generic agents will have broad clinical applicability across the diverse HCC etiologies and clinical contexts and are expected to substantially improve the still dismal prognosis of HCC.
Catalytic radical difluoromethoxylation of arenes and heteroarenes

Intermolecular C-H difluoromethoxylation of (hetero)arenes remains a long-standing and unsolved problem in organic synthesis. Herein, we report the first catalytic protocol employing a redox-active difluoromethoxylating reagent 1a and photoredox catalysts for the direct C-H difluoromethoxylation of (hetero)arenes. Our approach is operationally simple, proceeds at room temperature, and uses bench-stable reagents. Its synthetic utility is highlighted by mild reaction conditions that tolerate a wide variety of functional groups and biorelevant molecules. Experimental and computational studies suggest single electron transfer (SET) from excited photoredox catalysts to 1a forming a neutral radical intermediate that liberates the OCF2H radical exclusively. Addition of this radical to (hetero)arenes gives difluoromethoxylated cyclohexadienyl radicals that are oxidized and deprotonated to afford the products of difluoromethoxylation.
Effect of Testosterone on Natriuretic Peptide Levels.

AbstractBackground: Circulating natriuretic peptide (NP) levels are markedly lower in healthy men than women. A relative NP deficiency in men could contribute to their higher risk of hypertension a...
Magnetic and tunable dielectric properties of DyCrO3 thin films

DyCrO3 (DCO) belongs to the family of rare-earth chromites, some members of which exhibit magnetoelectric multiferroic properties. This work characterizes the dielectric tunability in DCO, which is typically, for conventional ferroelectrics, found to maximize near the ferroelectric to paraelectric transition. Two films of DCO were fabricated via a hybrid solution synthesis route on different substrates: one on single crystalline (001) LaAlO3 (LAO) and the other on (001) LAO coated with a conducting LaNiO3 (LNO) layer. The synthesis method resulted in films with both out-of-plane and in-plane texture in the DCO. The lattice mismatch strain between film and substrate caused a slight increase in the Neel temperature of the DCO film on LAO. Transmission electron microscopy images of the DCO film on the LNO/LAO revealed the epitaxial relationship between these phases. The temperature dependence of the relative permittivity showed diffused transition and a frequency dispersion similar to what is observed in typical relaxor ferroelectrics. Isothermal dielectric constant versus dc electric field measurements showed an electric field tunable relative permittivity (i.e., tunability). This tunability reached a broad plateau near the Neel temperature. Such maxima in dielectric tunability are typically observed near a ferroelectric–paraelectric transition, and its proximity to the magnetic ordering temperature in DCO indicates magnetically driven ferroelectricity in this material.
Emerging market startups engage Silicon Valley: Cases from Central and Eastern Europe

This article examines the challenges and opportunities of innovation-driven growth in Central and Eastern Europe. Drawing on firm-level survey research, we analyze the experiences of early stage Polish companies in Silicon Valley. We focus on the Polish Silicon Bridge, an international bridge organization that differs from conventional business incubators and accelerators by embedding emerging market startup companies in foreign innovation hubs. We situate the analysis in the context of the “Polish Paradox”. While Poland ranks as one of the European Union’s fastest growing economies over the past two decades, it is one of the EU’s weakest performers measured by innovation. The Silicon Bridge program aims to expand Poland’s innovation capacity by placing promising local startups in the world-class ecosystem of the San Francisco Bay Area. Our empirical study demonstrates that international bridge organizations generate significant benefits–knowledge acquisition, mentoring, networking with prospective investors and strategic partners–for young emerging market companies seeking to enter the global market. The article thus augments the scholarly literature on global innovation ecosystems, entrepreneurial internationalization, and emerging market startups.
Chapter 14 – Chemotherapeutics

Chemotherapeutics are chemical entities used to treat or cure cancers. These agents target critical processes for cell division in rapidly growing cancer cells. Most cancer drugs are derived from natural sources such as plants and bacteria, other are derived from synthetic or semisynthetic processes. Cancers can arise in virtually all tissues of the body, but the frequency of incidences varies depending on genetic influence, diet, lifestyle and environmental exposures. The most common cancers worldwide are lung, breast and prostate cancers which have had increased survival due to improvements in diagnoses and treatment options. Naturally derived agents have been the mainstay of cancer therapy and the potential to uncover endemic compounds that may exhibit potent anticancer properties has driven research for novel anticancer agents. A number of active agents or extracts from plants extracts have been studied for their anti-cancer properties, some of these will be discussed herein.
Cybersecurity: a predictive analytical model for software vulnerability discovery process

A software vulnerability is defined as a flaw that exists in computer resources or control that can be exploited by one or more threats. Vulnerabilities are discovered throughout the entire life cy...
The detection of pentobarbital in euthanized domestic dogs

This preliminary study examined the postmortem distribution of pentobarbital in the remains of three domestic dogs (Canis lupus familiaris) after intravenous administration of pentobarbital sodium to determine optimal sampling practices for veterinary forensic casework. It was thought that pentobarbital would be absent in many traditional toxicological samples, such as bile and urine, because of the brief period between administration and death. However, all samples tested via gas chromatography, coupled with a nitrogen–phosphorus detector, contained quantifiable levels of pentobarbital. These initial results suggest that when the Florida Animal Control Association’s recommended method of euthanasia is used in healthy individuals, pentobarbital extensively distributes throughout the body.
Data-driven Cyberattack Detection for Photovoltaic (PV) Systems through Analyzing Micro-PMU Data

With increasing exposure to software-based sensing and control, Photovoltaic (PV) systems are facing higher risks of cyber attacks. To ensure the system stability and minimize potential economic losses, it is imperative to monitor operating states and detect attacks at the early stage. To meet this demand, Micro-Phasor Measurement Units (µPMU) are increasingly popular in monitoring distribution networks. However, due to the relatively low sampling rate, µPMU has not yet been used to detect and classify cyber-attacks in power electronics enabled smart grid. To our knowledge, this is one of the first attempts to use µPMU to detect cyber attacks that degrade the performance of power electronics systems. We propose to apply data-driven methods on micro-PMU data to implement attack detection. We have evaluated data-driven methods, including decision tree (DT), K-nearest neighbor (KNN), support vector machine (SVM), artificial neural network (ANN), long short-term memory (LSTM) and convolutional neural network (CNN). The proposed CNN model achieves the required performances with the highest 99.23% accuracy and 0.9963 F 1 score.
U.S. facts-available antidumping decisions: An empirical analysis

Abstract This paper analyzes U.S. implementation of one aspect of antidumping reform agreed to in the Uruguay Round. In particular, evidence is consistent with the view that administrators have not fundamentally improved the application of “facts-available” techniques, which is an important contributor to high antidumping margins on U.S. imports. The results suggest that the U.S. has lived up to the letter but not the spirit of one important antidumping reform in the Uruguay Round.
Belonging in STEM: Growth Mindset as a Filter of Contextual Cues

Undergraduate students in science, technology, engineering, and mathematics (STEM) programs face unique challenges to their psychological well-being, including their sense of belonging. Recent evidence suggests that beliefs about the malleability of intelligence (growth mindsets) support STEM students’ belongingness, though the mechanisms of this relationship are unclear. We propose and test a model in which students’ personal growth mindset beliefs relate to their sense of belonging by operating as a filter of environmental cues, especially those signaling instructors’ mindsets, peers’ mindsets, and the school’s trustworthiness. Across more than 3000 students in two diverse STEM contexts, we found general support for this model (mean RMSEA = 0.041; mean R2 = 39%). Perceived environmental cues fully mediated (Study 1) and partially mediated (Study 2) the total effect of personal growth mindset on belonging. In addition to model generalizability, there was meaningful heterogeneity in the results observed across contexts. These results suggest a novel filtering function of growth mindsets for belonging. Discussion centers on the factors that may account for model variability, as well as theoretical and practical implications of the findings.
Stereotypically gay- and straight-sounding auditory cues change adolescent music students’ perceptions of men’s teaching effectiveness:

The purpose of this study was to explore the effects of a stereotypically gay-sounding voice on middle- and high-schooler’s perceptions of teaching effectiveness. Participants (N = 273) listened to...
Ovarian cancer arising from the proximal fallopian tube in a patient with a BRCA2 mutation

Abstract Patients with BRCA mutations are at high risk of high grade serous ovarian cancer. A paradigm shift has resulted in the current understanding that many cases of ovarian cancer actually arise from the fimbriated fallopian tube. The case presented here involves fallopian tube carcinoma arising from the cornua of the uterus in a BRCA2 carrier. This case suggests that pathologic analysis of risk-reducing bilateral salpingo-oophorectomy (RRBSO) specimens via serial sectioning and extensively examining the fimbriated end (SEE-FIM) may be insufficient to diagnose all occult lesions of interest. This case also provides a new consideration in the ongoing debate over the role of concurrent hysterectomy at time of RRBSO in BRCA carriers.
Bridging M/EEG Source Imaging and Independent Component Analysis Frameworks Using Biologically Inspired Sparsity Priors

Electromagnetic source imaging (ESI) and independent component analysis (ICA) are two popular and apparently dissimilar frameworks for M/EEG analysis. This letter shows that the two frameworks can be linked by choosing biologically inspired source sparsity priors. We demonstrate that ESI carried out by the sparse Bayesian learning (SBL) algorithm yields source configurations composed of a few active regions that are also maximally independent from one another. In addition, we extend the standard SBL approach to source imaging in two important directions. First, we augment the generative model of M/EEG to include artifactual sources. Second, we modify SBL to allow for efficient model inversion with sequential data. We refer to this new algorithm as recursive SBL (RSBL), a source estimation filter with potential for online and offline imaging applications. We use simulated data to verify that RSBL can accurately estimate and demix cortical and artifactual sources under different noise conditions. Finally, we show that on real error-related EEG data, RSBL can yield single-trial source estimates in agreement with the experimental literature. Overall, by demonstrating that ESI can produce maximally independent sources while simultaneously localizing them in cortical space, we bridge the gap between the ESI and ICA frameworks for M/EEG analysis.
Theoretical constraints: Science, caretaking, and the creation of normative ideals.

OBJECTIVES This review explores the dualism in evolutionary anthropology that both acknowledges a broad range of familial caretaking strategies, while also remaining tethered to theories scaffolded around notions of selfish genes that constrain our understanding of who provides adequate kin care. I examine the process of norm creation in the sciences by investigating how theory may limit which data are collected and how those data are interpreted. METHODS This paper serves as a literature review and critique of prominent biological, evolutionary, and psychological conceptualizations of parental investment and caretaking in humans, and how these studies shape what is considered normal behavior in scientific literature. RESULTS Quantification, assessment, and theory building in evolutionary anthropology, and an oversampling of WEIRD communities in other disciplines, have limited our understanding of what constitutes both evolutionarily adaptive behaviors, and culturally specific human behaviors. CONCLUSIONS A synthetic theoretical model of behavioral norms in childrearing must account for an exchange of psycho-social and cultural resources and skills, the transfer of energetic reserves via gestation and lactation, and the indirect benefits of genetic inheritance. The emphasis on tailoring data collection to fit evolutionary theories of the family has limited our ability to understand the diverse proximate mechanisms that humans employ in taking care of kin as biocultural reproducers.
From Photobook to Digital Book: Curating Weimar Germany’s New Visual Literacy Online

This contribution focuses on the digital curation of Weimar Germany’s new visual literacy, using Kurt Tucholsky and John Heartfield’s photobook Deutschland, Deutschland uber Alles as a case study t...
Targeting the mTOR Pathway in Hurthle Cell Carcinoma Results in Potent Anti-Tumor Activity.

Hurthle cell carcinomas (HCC) are refractory to radioactive iodine and unresponsive to chemotherapeutic agents, with a fatality rate that is the highest among all types of thyroid cancer after anaplastic thyroid cancer. Our previous study on the genomic landscape of HCCs identified a high incidence of disruptions of mTOR pathway effectors. Here, we report a detailed analysis of mTOR signaling in cell line and patient-derived xenograft (PDX) mouse models of HCCs. We show that mTOR signaling is upregulated and that targeting mTOR signaling using mTOR inhibitors suppresses tumor growth in primary tumors and distant metastasis. Mechanistically, ablation of mTOR signaling impaired the expression of p-S6 and cyclin A2, resulting in the decrease of S phase and blocking of cancer cell proliferation. Strikingly, mTOR inhibitor treatment significantly reduced lung metastatic lesions, with the decreased expression of Snail in xenograft tumors. Our data demonstrates that mTOR pathway blockade represents a novel treatment strategy for HCC.
The Role of Nonassociative Algebra in Projective Geometry

There is a particular fascination when two apparently disjoint areas of mathematics turn out to have a meaningful connection to each other. The main goal of this book is to provide a largely self-contained, in-depth account of the linkage between nonassociative algebra and projective planes, with particular emphasis on octonion planes. There are several new results and many, if not most, of the proofs are new. The development should be accessible to most graduate students and should give them introductions to two areas which are often referenced but not often taught. On the geometric side, the book introduces coordinates in projective planes, relates coordinate properties to transitivity properties of certain automorphisms and to configuration conditions. It also classifies higher-dimensional geometries and determines their automorphisms. The exceptional octonion plane is studied in detail in a geometric context that allows nondivision coordinates. An axiomatic version of that context is also provided. Finally, some connections of nonassociative algebra to other geometries, including buildings, are outlined. On the algebraic side, basic properties of alternative algebras are derived, including the classification of alternative division rings. As tools for the study of the geometries, an axiomatic development of dimension, the basics of quadratic forms, a treatment of homogeneous maps and their polarizations, and a study of norm forms on hermitian matrices over composition algebras are included.
Innovation, Technology and Decision Making: A Perspective for Strategic Action in Firms

Innovation, technology, and the making of decisions are tightly intertwined in what can generally be called, strategic decision making. Although true for all firms, it is especially true in innovative, high technology firms that operate in a turbulent, fast moving environment where strategic decisions must be made accurately and quickly to survive. This paper looks at some factors reported in the literature that affect how and why the strategic decision process is so important, especially in companies in fast-moving, competitive environments. The work of several prominent authors who looked critically at past theory and research, and the current state of knowledge and practice, provides a perspective of how firms make strategic decisions.
The Shower Bath

(1930). The Shower Bath. The Journal of Health and Physical Education: Vol. 1, No. 5, pp. 6-8.
Measurement of TFT/LCD Flicker for ISO Compliance

Abstract Flicker is one of the major concerns in the design of computer display, and there have been many research reports on measuring and predicting flicker in order to provide users with flicker-free displays. Most of the previous studies, however, have been based on CRT displays. In this study, flicker on a thin-film transistor liquid crystal display (TFT/LCD) was measured by using a subjective evaluation method. The purpose of the study was to ascertain whether the TFT/LCD conform to ISO standards on flicker, and to determine the main factors affecting flicker on the TFT/LCD. The results indicate that the TFT/LCD used in the study met the ISO standards at frame frequency as low as 35 Hz when all-pixels-on patterns were displayed. It was found that the common voltage (Vcom) is one of the most important factors affecting flicker on the TFT/LCD, and that the Vcom should be well-balanced to make the TFT/LCD flicker-free. It was also found that the analytic method proposed in ISO/CD 13406-2 was not always appropriate for predicting flicker on the TFT/LCD.
Design of optimal motion for flight simulators

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1983.
Growth of T-Strain Mycoplasmas in Medium Without Added Urea: Effect of Trace Amounts of Urea and of a Urease Inhibitor

Urea is currently considered to be a requirement for the propagation of T-strain mycoplasmas. We report here the replication of T-strain 960 (ATCC 25023) in media prepared from dialyzed components with added putrescine and allantoin but without added urea, or in dialyzed medium containing small amounts of added urea. The least amount of urea which allowed growth in the medium without allantoin was above 10 μg/ml. The amount of urea estimated to contaminate the added allantoin or putrescine was 5 μg/ml or less, which is insufficient to support T-strain replication. T-strain 960 was grown in the presence of urea and the urease inhibitor acetohydroxamic acid AHA where the organisms multiplied at a slower rate in the presence of AHA than in its absence. Urea hydrolysis occurred with concomitant ammonia accumulation and pH increase in cultures with AHA added.
Overexpression of PTEN/MMAC1 and Decreased Activation of Akt in Human Papillomavirus-infected Laryngeal Papillomas

Laryngeal papillomas are benign, human papillomavirus-induced hyperplastic tumors of the respiratory tract. They are characterized by overexpression of the epidermal growth factor receptor, constitutive activation of mitogen-activated protein kinase, a low proliferative rate, and defects in differentiation. We have now found that phosphoinositol 3-kinase (PI 3-K) activity is significantly increased in papilloma tissue. However, phosphorylated Akt (also known as protein kinase B), a downstream effector of PI 3-K, is reduced when compared with normal tissue. The ratio of activated Akt to total Akt is much lower in papillomas than in normal laryngeal tissue, suggesting decreased Akt activation. PTEN/MMAC1 is a tumor suppressor that dephosphorylates phosphatidylinositol 3,4,5-triphosphate, an intermediate in the PI 3-K/Akt signaling pathway. We have found that PTEN protein is overexpressed in laryngeal papillomas when compared with normal laryngeal tissues. On the basis of reverse transcription-PCR analysis, PTEN mRNA is more abundant in papillomas, suggesting transcriptional up-regulation. We postulate that negative regulation of the PI 3-K/Akt pathway by PTEN may modulate the effects of the hyperactive epidermal growth factor receptor/mitogen-activated protein kinase pathway, contributing to the low proliferation and dysfunctional differentiation of laryngeal papillomas.
Informational Speculative Attacks: Good News is No News

The behavior of capital flows during the onset of a currency crisis has been an important question in recent economic literature. The apparent overreaction of financial markets has been pointed out, by several economists, as one of the major factors contributing to the magnification of the crises. This paper develops a simple model in which investors face uncertainty about the underlying fundamentals of the economy and the learning process is affected by the agents' actions. Three characteristics of recent speculative attacks are captured by the model: the excess volatility in capital flows, why these types of problems are more likely to occur in developing countries, and why the attacks tend to be concentrated in time and regions.
Spin flipping with an rf dipole and a full Siberian snake

We recently used an rf dipole magnet to study the spin flipping of a 120 MeV horizontally polarized proton beam stored in the presence of a nearly full Siberian snake in the Indiana University Cyclotron Facility Cooler Ring. We flipped the spin by ramping the rf dipole's frequency through an rf-induced depolarizing resonance. After optimizing the frequency ramp parameters, we used multiple spin flips to measure a spin-flip efficiency of $86.5\ifmmode\pm\else\textpm\fi{}0.5%$. The spin-flip efficiency was apparently limited by the field strength in the rf dipole. This result indicates that spin flipping a stored polarized proton beam should be possible in high energy rings such as the Brookhaven Relativistic Heavy Ion Collider and HERA where Siberian snakes are certainly needed and only dipole rf-flipper magnets are practical.
Dynamical probes of thermal and electronic effects in laser etching of silicon

Band gap illumination of a semiconductor surface produces elevated populations of charge carriers which can directly influence surface reactions as well as recombine to generate heat. Previous studies have established that when light intensities are low, i.e., heating is minimal, photogenerated charge carriers can enhance the rate of reaction between silicon and XeF2.1,2 The mechanism for this has been proposed to involve trapping of electrons and holes at the surface, thereby increasing the relative reactivity of precursors to the etch products. These data, obtained at low levels of illumination, are not directly applicable to the more complicated situation of laser-induced etching under high-power-density conditions, where surface heating and substrate phase changes are important.
Restoration Benefits to Natural Springs in the Lake Mary Watershed

Abstract Hoxworth Springs are one of several natural spring systems located within the Lake Mary Watershed in northern Arizona. The springs serve as critical water resources and contribute to the overall water budget for Lake Mary. Lake Mary is an artificial reservoir that supplies municipal drinking water for Flagstaff, Arizona, and surrounding communities. This area is therefore important to overall water security in the region and necessitates prioritization of its natural integrity. Springs that feed into the greater Lake Mary watershed form wetlands in the immediate area, which provides wetland habitat in an otherwise arid ecosystem matrix. Wetlands provide numerous benefits and ecosystem services including water purification, increased biodiversity and ecosystem health. However, these important wetlands and spring systems are in danger of disappearing due to increased demand for groundwater and mismanagement of land surrounding these streams. Activities that lead to changes in land use include fire ...
Normal Serum Calcium Levels by Atomic Absorption Spectroscopy

Normal adult calcium levels were established with the atomic absorption spectrophotometric technic of Zettner and Seligson ( 1 ). Significant differences in calcium concentration were shown to exist between the sexes. Three commonly employed serum treatment technics were compared; two gave equivalent results.
Sodium and Silicon as Nutrients for the Tomato Plant.

The possible essentiality of sodium, silicon, and aluminum in the nutrition of higher plants has been the subject of controversy for many years. The fact that these elements are almost ubiquitous has made the problem of ascertaining their status extremely difficult. This study was undertaken to determine at what level any one of these three elements might be needed by the tomato plant, if it were essential for the growth and development of this plant. Most techniques for critically investigating essentiality of nutrient elements involve the extensive use of Pyrex laboratory glassware in all phases of the investigations. That this glassware is soluble to a certain extent is well known. Wichers, Finn, and Clabaugh (8) gave figures for the solubility of Pyrex glass #774 in hot distilled water. Further, it has been the experience in this laboratory that at least part of the boron requirement of plants could be obtained from Pyrex beakers in which the plants were cultured. In view of this fact and from a consideration of the composition of Pyrex (8), it would seem possible that plants might obtain significant amounts of ? a, Si, and Al from such containers. Fortunately, the increasing availability of polyethylene ware, coupled with the increasing purity of the salts available from the chemical supply houses, has provided means by which the study of the possible essentiality of these three elements has been made practical. Al was added as a treatment in these experiments because this element is one which could probably be supplied by Pyrex glassware, but no Al analyses were made.
Mechanisms and management of proarrhythmia

Abstract It is now well recognized that therapy with antiarrhythmic drugs can not only suppress cardiac arrhythmias, but also may increase their frequency or provoke new ones. Specific proarrhythmia syndromes, each with a distinct underlying mechanism and approach to therapy, have been described. The best-recognized examples are digitalis intoxication, proarrhythmia associated with sodium-channel block, and torsade de pointes occurring during QT-prolonging therapies. In the case of sodium-channel blockers, 2 forms of proarrhythmia are commonly recognized: slow atrial flutter with 1 : 1 atrioventricular conduction, and frequent ventricular tachycardia ([VT], most often found in patients with pre-existing VT reentrant circuits). In all cases, the best approach to therapy is to identify patients at risk (and thereby avoid therapy entirely), to recognize proarrhythmia when it occurs, to withdraw offending agent(s), and to use specific corrective therapies when available. Although most recognized episodes of proarrhythmia are thought to occur early in drug therapy, the increased mortality during chronic antiarrhythmic therapy demonstrated in large randomized trials suggests this phenomenon can also develop during long-term drug treatment. The recognition of proarrhythmia and the delineation of its underlying mechanisms should not only improve therapy with available drugs, but may also direct development of newer agents devoid of this potential.
The Management of Treatment-Experienced HIV-Infected Patients: New Drugs and Drug Combinations

The recent availability of new antiretroviral agents for the treatment of human immunodeficiency virus (HIV) infection has increased treatment options and has improved the durability, tolerability, and long-term efficacy of antiretroviral therapy, even among patients with extensive treatment experience and high levels of drug resistance. This expansion of therapeutic options has led to a revision of current treatment guidelines, which now state that the goal of antiretroviral therapy in all patients is suppression of the plasma HIV RNA level to <50 copies/mL. Successful management of infection for treatment-experienced patients with the new agents requires an understanding of their pharmacology and resistance patterns and the appropriate use of laboratory testing to optimize regimen selection. This review discusses the use of recently approved antiretroviral agents in the management of HIV infection in treatment-experienced patients.
Effects of the Low Frequency Electromagnetic Field on the Centerline Macrosegregation of 7075 Aluminum Ingots

The effects of the low frequency electromagnetic field on the macrosegregation of the 7075 aluminum ingots were investigated. The 7075 aluminum ingots with the diameter of 200 mm were prepared by the conventional direct chill casting and the low frequency electromagnetic field casting (LFEC) processes, respectively. The temperature during casting at steady state was measured, and the mushy region was observed from the temperature contour. The concentrations of the alloying elements were measured by the spectrograph. It was found that the transition region was broadened, but the mushy zone became narrower with presence of the low frequency electromagnetic field. The centerline macrosegregation of the ingots was alleviated by the low frequency electromagnetic casting process.
Ecological strategies in California chaparral: interacting effects of soils, climate, and fire on specific leaf area

Background: High values of specific leaf area (SLA) are generally associated with high maximal growth rates in resource-rich conditions, such as mesic climates and fertile soils. However, fire may complicate this relationship since its frequency varies with both climate and soil fertility, and fire frequency selects for regeneration strategies (resprouting versus seeding) that are not independent of resource-acquisition strategies. Shared ancestry is also expected to affect the distribution of resource-use and regeneration traits. Aims: We examined climate, soil, and fire as drivers of community-level variation in a key functional trait, SLA, in chaparral in California. Methods: We quantified the phylogenetic, functional, and environmental non-independence of key traits for 87 species in 115 plots. Results: Among species, SLA was higher in resprouters than seeders, although not after phylogeny correction. Among communities, mean SLA was lower in harsh interior climates, but in these climates it was higher...
Synthesis of multi‐unit protein hetero‐complexes in the gas phase via ion–ion chemistry

The synthesis of protein hetero-complex ions via ion–ion reactions in the gas phase is demonstrated in a quadrupole ion trap. Bovine cytochrome c cations and bovine ubiquitin anions are used as reactant species in the stepwise construction of complexes containing as many as six protein sub-units. For any set of reactants, a series of competitive and consecutive reactions is possible. The yield of complex ions for any given sequence of reactions is primarily limited by the presence of competitive reactions. Proton transfer represents the most important competitive reaction that adversely affects protein complex synthesis. In the present data, proton transfer takes place most extensively in the first step of complex synthesis, when single protein sub-units are subjected to reaction with one another. Proton transfer is found to be less extensive when one of the reactants is a protein complex. The generation of hexameric hetero-complexes containing two cytochrome c molecules and four ubiquitin molecules is demonstrated with two different synthesis approaches. The first involved the initial reaction of several charge states of cytochrome c and several charges states of ubiquitin. The sequence of reactions in this example illustrates the array of possible competitive and consecutive reactions associated with even a relatively simple set of multiply charged reactants. The second approach involved the initial reaction of the 9+ charge state of cytochrome c and the 5− charge state of ubiquitin. The latter approach highlights the utility of the multi-stage mass spectrometric (MSn) capabilities of the ion trap in defining reactant ion identities (i.e. charge states and polarities) so that synthesis reactions can be directed along a particular set of pathways. Copyright © 2004 John Wiley & Sons, Ltd.
Pivotal Steps Towards Quantification of Molecular Diffusion Coefficients by NMR

Using nuclear magnetic resonance (NMR) spectroscopy with a pair of pulsed field gradients (PFGs), Stajeskal and Tanner successfully measured molecular diffusion coefficients in solution in 1965. This method has since been used extensively in various applications, especially after the PFG was implemented in commercial NMR probes. Due to the nonuniformity of the PFG and radio frequency (RF) fields, molecules distributed throughout the sample experience different PFG and RF fields and contribute unevenly to the measured diffusion coefficients, resulting in considerable errors in conventional NMR diffusion experiments. By selective excitation of a central sample region with an offset-independent adiabatic inversion pulse and a PFG, a uniform RF field can be assumed, and the PFG can be represented as a linear approximation. Under these conditions, the molecules diffuse as if they were all experiencing the same effective gradient g(e), leading to a Gaussian signal decay as a function of the PFG strength. Quantitative measurement of molecular diffusion coefficients is therefore made possible. From the diffusion coefficient of a 90 % H(2)O/10 % D(2)O sample, it is convenient to calibrate g(e) with a Java program. In a similar way the nonlinearity of the PFG can be corrected.
Aggressive organ donor management significantly increases the number of organs available for transplantation.

Background:The shortage of transplantable organs has become a national crisis. Despite various attempts to expand the donor pool, the difference between organ supply and organ demand continues to widen. With no foreseeable increase in the number of donors, it is necessary to maximize the utilization
Experimental and Analytical Sonic Nozzle Discharge Coefficients for Reynolds Numbers up to 8×106

Sonic discharge coefficients are presented for two different geometry flow nozzles using nitrogen gas at high pressures where real-gas corrections are significant. Throat Reynolds number range extended up to 8,000,000. Experimentally obtained coefficients for a nozzle with a continuous and finite radius of curvature agreed with those obtained analytically to within 0.2 per cent. Experimental coefficients for a long-radius ASME nozzle agreed to within 0.25 per cent to an empirical equation representing the most probable subsonic discharge coefficient.
Naturalistic, self-assignment comparative trial of bupropion SR, a nicotine patch, or both for smoking cessation treatment in primary care

The effectiveness of bupropion SR, a nicotine patch, or both, when co-administered with cognitive-behavioral therapy, on smoking cessation was evaluated under treatment-as-usual conditions in a primary care smoking cessation clinic. Consecutive consenting patients (n = 189) assigned themselves to one of three treatments according to personal preference: nicotine patch (NTP; n = 27), bupropion SR (B; n = 101), and bupropion SR plus nicotine patch (B + NTP; n = 61). Six-month self-reported abstinence rates were 14.8%, 27.7%, and 34.4%, respectively. Odds ratios for 6-month abstinence, with NTP as reference, were 2.2 (CI = 0.7-5.9; p = .19) for B, and 3.0 (CI = 0.9-9.9; p = .07) for B + NTP. Resemblance of abstinence pattern and magnitude between this naturalistic study and randomized clinical trials of bupropion SR may support tentative inferences of stability and generalizability of clinical trial efficacy findings.
On the anticorrelation of the electric field and peak electron energy within an auroral arc

The present investigation is concerned with an example of a strongly anticorrelated electric field and particle precipitation, taking into account an application of an extended version of the model of Evans et al. (1977) to the data. A striking feature of the data reported is the high degree of anticorrelation between electric field strength and peak precipitating electron energy. A simple model consisting of a constant current traversing a region in which the conductivities increase in proportion to ionospheric energy deposition provides a qualitative explanation of the observations. However, when the effects of neutral winds, ionization transport, Hall currents, and arc motion, and the nonlinearity of the relationship between peak precipitating electron energy and equilibrium are considered, the conclusions become less clear.
The Risk of Nursing Home Placement and Subsequent Death Among Older Adults

This article examines the effects of the characteristics specified in the behavioral model of health services utilization and measured at baseline on the subsequent risk of nursing home placement and death within four years. Analyses of the 5,151 respondents in the Longitudinal Study on Aging indicate that the risk for nursing home placement is greater for older adults, Whites, those who lived alone, persons with telephones, those with fewer nonkin social supports, those who did not feel that they had much control over their future health, those with more household ADL or lower body limitations, and those who had been in the hospital during the year prior to baseline, or in a nursing home at any time before baseline. Among the 549 respondents placed in nursing homes, the risk of dying there was greater for older adults, men, those who had not lived in multigenerational households, persons who did not worry about their health, individuals with more upper body limitations, and respondents having a history of valvular heart disease or cancer. The odds of dying were 2.74 times greater among the 549 respondents placed in nursing homes than among the 4,602 respondents who remained in the community.
Evaluation of Children With Palpitations

Palpitations are a common symptom in children and adolescents presenting to the emergency department. The differential diagnosis can range from benign etiologies to life-threatening dysrhythmias. Although the most common causes of palpitations in pediatric patients are benign, the emergency department physician is charged with determining which patients would require immediate management, workup, and referral to a cardiologist. This article will specifically address the symptom of palpitations in pediatric patients, isolating it from the more frequently reviewed subject of chest pain.
Reevaluation of toluidine blue application as a diagnostic adjunct in the detection of asymptomatic oral squamous carcinoma: a continuing prospective study of oral cancer III.

This study was initiated to evaluate toluidine blue application as a worthwhile and simple diagnostic adjunct to clinical impressions. In an attempt to decrease false positives, a 10--14 day waiting period was initiated to allow inflammatory lesions to resolve before application of stain. Using toluidine blue applications with 235 prospectively documented persistent lesions (105 carcinomas and 130 nonmalignant lesions) resulted in a false negative rate (underdiagnosis) of 6.7% and false positive rate (overdiagnosis) of 8.5%. Using clinical criteria alone resulted in a false negative rate of 4.8% but with a tendency to overdiagnose--28.5% false positives. Combining both diagnostic modalities reduced the false negative rate to 1.9%, i.e., only two of the 105 cancers were not considered significant by toluidine blue stain or clinical impression. This staining technique appears to offer a feasible diagnostic "control" over the subjective impression of the clilnician. Persistent lesions that stain with toluidine blue should be considered carcinoma unless proven otherwise by biopsy.