cssi/SciSciGPT-SciSciNet huggingface dataset:
Congenitally absent superior mesenteric artery in an asymptomatic adult

Abstract Congenitally absent superior mesenteric artery is an extremely rare anatomic anomaly with only one other case reported in an adult. We have described an elderly patient who presented with complete absence of the superior mesenteric artery found incidentally on computed tomography imaging. The patient had no abdominal pain, nausea, or other gastrointestinal symptoms. An abnormally enlarged inferior mesenteric artery provided collateral circulation to the midgut. No intervention was performed at the time given the patient's adequate circulation and lack of symptoms. The present case highlights consideration of anatomic mesenteric vascular anomalies before procedures involving inferior mesenteric artery ligation or coverage.
The Impact of a Mentor: The Course of a Life: The High Impact of Undergraduate Research and Mentoring

The trajectory of my life changed in the most mundane of ways. It was on the first day of classes during my junior year in college. While seated at a desk in a classroom in the Armory at the University of Illinois, I awaited eagerly for what would be my first upper-division history course: Professor Robert McColley’s course on Early National America, which covered the period roughly from the 1780s to the 1820s. After introducing the class, the professor handed out a list of topics and assigned one of them to each of us. My topic was William Blount (1749-1800). Who was William Blount, I wondered. The assignment was to write a research paper that would be due at the end of the semester.
Novel Semi-parametric Tobit Additive Regression Models

Regression method has been widely used to explore relationship between dependent and independent variables. In practice, data issues such as censoring and missing data often exist. When the response variable is (fixed) censored, Tobit regression models have been widely employed to explore the relationship between the response variable and covariates. In this paper, we extend conventional parametric Tobit models to a novel semi-parametric regression model by replacing the linear components in Tobit models with nonparametric additive components, which we refer as Tobit additive models, and propose a likelihood based estimation method for Tobit additive models. %The proposed estimation method is computational efficient and easy to implement. Numerical experiments are conducted to evaluate the finite sample performance. The estimation method works well in finite sample experiments, even when sample size is relative small.
Gifted for whom? Individualism, dyadism, and collectivism in the definition of giftedness:

Gifts can be individually, dyadically, or collectively chosen and oriented. Society, in its identification of the gifted, has chosen to focus on individual and sometimes dyadic goods. This practice...
Jitk: a trustworthy in-kernel interpreter infrastructure

Modern operating systems run multiple interpreters in the kernel, which enable user-space applications to add new functionality or specialize system policies. The correctness of such interpreters is critical to the overall system security: bugs in interpreters could allow adversaries to compromise user-space applications and even the kernel.Jitk is a new infrastructure for building in-kernel interpreters that guarantee functional correctness as they compile user-space policies down to native instructions for execution in the kernel. To demonstrate Jitk, we implement two interpreters in the Linux kernel, BPF and INET-DIAG, which are used for network and system call filtering and socket monitoring, respectively. To help application developers write correct filters, we introduce a high-level rule language, along with a proof that Jitk correctly translates high-level rules all the way to native machine code, and demonstrate that this language can be integrated into OpenSSH with tens of lines of code. We built a prototype of Jitk on top of the CompCert verified compiler and integrated it into the Linux kernel. Experimental results show that Jitk is practical, fast, and trustworthy.
Book Review: Paul Outka's "Race and Nature from Transcendentalism to the Harlem Renaissance"

Reviews Paul Outka's _Race and Nature from Transcendentalism to the Harlem Renaissance_ (2008).
Recent and dramatic changes in Pacific storm trajectories recorded in δ18O from Bristlecone Pine tree ring cellulose

[1] A 300-year stratigraphy of annual cellulosic δ18OVSMOW is presented for the long-lived Bristlecone Pine (Pinus longaeva) from the White Mountains of California. The δ18OVSMOW stratigraphy exhibits two distinctive characteristics: a bidecadal oscillation during the 20th century with peak excursions of 4‰ and a dramatic 9‰ shift in mean δ18O values in the mid-19th century. The bidecadal δ18O variability during the 20th century does not correlate well with the bidecadal pattern of drought recurrence as reflected in the Palmer Drought Severity Index. Geochemical modeling of the cellulose δ18OVSMOW indicates local climate conditions, particularly humidity and rainfall amount, should have been important influences on the cellulose δ18O variability, but these influences cannot explain the larger bidecadal excursions or the shift in values during the mid-19th century. The large isotope variations must reflect sustained shifts in the frequency of subtropical versus polar storms that affect the isotopic composition of rainfall at the site. The mid-19th century isotopic shift correlates with the major climate shift across the northern hemisphere as documented in a wide range of proxy records. We hypothesize that the large isotopic shift in the 19th century represents the hydrologic response to a regime shift in mean wintertime atmospheric circulation that changed storm trajectories brought about by a more southerly position of the midlatitude jet, increased trade wind strength, and a change in the frequency of the Pacific Decadal Oscillation. The extent to which the hydrologic changes influenced the growth behavior of the high-altitude Bristlecone Pine in the White Mountains remains an important unanswered question.
Impediments of educational bureaucrats on teacher education in Nigeria

This paper set out to discuss the impediments of educational bureaucrats on teacher education in Nigeria and to examine the person of the education bureaucrat, their functions in Nigeria context, their management behaviors and why they failed in the country. It was expected that at the end of the day stakeholders in teacher education would be able to have a positive orientation and understanding of the place of educational bureaucrats in the success of the country’s educational enterprise in teacher education. Nigeria has not been so lucky with good educational bureaucrats in all her endeavors in general and in schools in particular. For this reason, this paper toiled with the future of children with compulsory miseducation in a context of schooling without education – a rebirth of the diploma disease. Therefore, it is recommended that the education bureaucrats should involve teachers, non-teaching staff and students as well as the community through Parent Teachers Association to enhance teacher education in the country.
The Hubbard model: Some Rigorous Results and Open Problems

The Hubbard model of interacting electrons, like the Ising model of spin-spin interactions, is the simplest possible model displaying many “real world” features, but it is much more difficult to analyze qualitatively than the Ising model. After a third of a century of research, we are still not sure about many of its basic properties. This mini-review will explore what is known rigorously about the model and it will attempt to describe some open problems that are possibly within the range of rigorous mathematical analysis.
Decomposing the Yield Curve

We construct an affine model that incorporates bond risk premia. By understanding risk premia, we are able to use a lot of information from well-measured risk-neutral dynamics to characterize real expectations. We use the model to decompose the yield curve into expected interest rate and risk premium components. We characterize the interesting term structure of risk premia -- a forward rate reflects expected excess returns many years into the future, and current slope and curvature factors forecast future expected returns even though they do not forecast current returns.
CHAPTER 3 - Qualitative Properties of Solutions to Elliptic Problems

Qualitative properties of solutions to elliptic equations can be interpreted in an extremely broad sense to include virtually every property of solutions. This chapter discusses concrete and/or geometric properties of solutions. In particular, it emphasizes the two properties of solutions: the shape of solutions and the stability of solutions. Boundary conditions clearly play important roles in the qualitative behavior of solutions. One feature of this survey is the inclusion of comparisons of the different, sometimes opposite effects of Dirichlet and Neumann boundary conditions, whenever possible. Qualitative properties of solutions are closely related to the existence of solution. In fact, existence of solutions provides the basis for the study of qualitative properties. On the other hand, searching for solutions with particular properties in mind could provide clues for existence.
Supernovae and Quasars

We attempt to show how the evolution of galactic nucleus of the special mass 108 M⊙’s leads preferentially to the radiation phenomena of quasars. Radiation flow greater than the Eddington limit leads to the correct mass flow and lifetime. The evolution of the stellar system leads to collision and massive stars; rapid supernovae give canonical neutron stars which in turn make much larger supernovae - brand X supernovae - when a small cold neutron star coalesces with a massive star. The high energy of ejected matter, 10 Mev per nucleon, and 4 × 1053ergs controls the matter density of the nebula of gas to thickness of ≃ 3 Compton mean free paths and electron temperatures of ≃ 1/2; mec2. These conditions are ideal for plasma wave photon emission at 2νp 108 Hz and effective plasma wave temperature of 1012 to 1013 mec2. A competition between heating these photons by plasma waves and cooling by electrons (stimulated Comton scattering) produces a steep photon density spectrum ∝ ν−3that is taken over by normal inverse Compton scattering at νcrit ≃ 1.5 × 1011 Hz. The change of slope produced at this frequency is characteristic of observations and fundamental to the theory. The large infrared emission comes from these photons further heated, times 100, by inverse Compton scattering before escaping from the nebula. Bremsstrahlung and inverse Compton scattering produce an equal X-ray luminoscity. The peculair properties of plasmon-photon scattering and stimulated Compton scattering produce a radio flux ∝ ν−1 and a possible explanation of the rapid apparent expansion v ≫ c of compact radio sources.
Bispectral index (BIS) and burst suppression : Revealing a part of the BIS algorithm

Objective. The bispectral index (BIS) is a complex EEG parameter which integrates several disparate descriptors of the EEG into a single variable. One of the subparameters incorporated in the BIS is the suppression ratio, quantifying the percentage of suppression during burst suppression pattern. The exact algorithm used to synthetize the information to the BIS value is unpublished and still unknown. This study provides insight into the integration of the suppression ratio into the BIS algorithm. Methods. EEG data of 10 healthy volunteers during propofol infusion were analyzed. Propofol concentrations were ramped up to 4 predetermined concentrations (1, 2, 3, 4, 6, 8, 9, or 12 µg/ml) using a computer controlled infusion pump (STANPUMP). EEG recordings were performed with an Aspect A-1000 EEG monitor (Version 3.22). The relationship of the processed EEG variables bispectral index and suppression ratio, calculated by the Aspect A-1000 monitor, was analyzed. Results. Up to 40% suppression ratio the average BIS values remained constant regardless of suppression ratios (r= 0.13). Beyond a suppression ratio of 40%, BIS and suppression ratio were invariably linearly correlated (r= −1). At a suppression ratio ≥ 40% the BIS value could be calculated as BIS = 50 – suppression ratio/2. Conclusions. Suppression ratio values > 40% are linearly correlated with BIS values from 30 to 0. An increasing anesthetic drug effect resulting in an increase of the duration of suppression to a suppression ratio up to 40% is not adequately reflected by the BIS value.
Studies on the galactic density wave

For spiral galaxies, investigations have been made as to the behaviour of density waves at the critical regions of the Lindblad and co-rotation resonances and in particular as to their role in the maintenance and generation of these waves. We shall also discuss the conditions under which an inner resonance ring may be formed. Furthermore, we find that the co-rotation region acts as a wave-amplifier.
Role of Inflammation in Cardiovascular Disease: How to Use C‐Reactive Protein in Clinical Practice

Acute coronary syndromes, stroke, and sudden death are common complications of a disrupted atherosclerotic plaque. Unstable plaque is a result of multiple factors but is commonly characterized by an infiltrate of inflammatory cells. Medical research strongly supports a role for inflammation in the pathogenesis, progression, and disruption of atherosclerotic plaque. Medical science also has improved our understanding of the complex interactions between our environment and our immune, coagulation, and cardiovascular systems. Clinical studies have demonstrated systemic markers of inflammation to be strong predictors of clinical events, and specific treatments of atherosclerosis and its risk factors have been associated with reductions in inflammatory markers. The authors review the current understanding of the role of inflammation in the pathogenesis of atherosclerosis, the common inflammatory markers, and potential anti-inflammatory therapy. Among several potential circulating markers of vascular inflammation, high sensitivity C-reactive protein is best validated and standardized as a marker for cardiovascular risk assessment. Nevertheless, there remain many uncertainties in utilizing C-reactive protein in clinical practice. Here, the authors describe the central role of C-reactive protein in atherosclerosis, review the studies demonstrating predictive value of C-reactive protein, describe the factors requiring consideration when utilizing C-reactive protein, discuss clinical scenarios in which measurement of C-reactive protein may be helpful, and suggest ways to interpret and treat elevated C-reactive protein levels. Finally, the authors summarize future expectations for assessing and modulating the vascular inflammation to inhibit initiation and progression of the atherosclerotic process.
Form Equivalence of the Selective Auditory Attention Test Administered to 6-Year-Old Children

The form equivalence of the Selective Auditory Attention Test (SAAT) was examined. Forty normal-hearing 6-year-old boys and girls were assigned randomly in equal numbers to one of two groups. Each ...
Clinical and Regulatory Features of Drugs Not Initially Approved by the FDA

US Food and Drug Administration (FDA) denials of New Drug Applications (NDAs) are often controversial, yet little is known about the basis and characteristics of these decisions. We reviewed new drugs and biologics evaluated by FDA advisory committees between 2007 and 2009 and found that half (27/52, 52%) were unapproved in the first cycle. By 2013, 63% had been approved. Products with initial safety concerns (62%) were much more likely to be approved eventually than drugs with efficacy concerns (8%).
A simple technique for determining joint losses on a coaxial line from swept-frequency reflection data

A need to separate connector loss from swept-frequency automatic network analyzer (ANA) measurements to check an attenuation calculation for a low-loss coaxial line has led to a simple graphical technique for determining joint losses. Measurements show that in addition to the connector loss, it is also possible to determine joint losses around center conductor bead supports on the line itself. Preliminary results indicate that losses in the millidecibel range can be determined to a precision of a few tenths of a millidecibel or better, even though the data are obscured by considerable connector loss and calibration error. Results were checked by independent measurements and show excellent agreement.
The association of echogenic fetal lungs with trisomy 21.

Objective To evaluate the association between echogenic appearing lungs on ultrasonographic examination of the fetus and aneuploidy. Methods Cases in which echogenic lungs were prospectively identified on ultrasonographic examination were collected. Other abnormal ultrasonographic findings were documented, as were patient data pertinent to the risk of aneuploidy, such as maternal age and results of serum screening. The chromosomal complement of each identified case is reported. Results Five fetuses were identified with diffusely echogenic lungs on ultrasound examination over a two-year period. In three of the five cases, there were other ultrasound abnormalities, although in only one of these was a major congenital abnormality detected. In all three of these cases, the fetal chromosomal complement showed trisomy 21. In 1 of the 2 cases in which the echogenic lungs were an isolated finding, the fetus also was found to have trisomy 21. Conclusions Bilateral and diffusely echogenic lungs appear to have an association with fetal trisomy 21. Copyright © 2005 John Wiley & Sons, Ltd.
Elective and emergency cardiac surgery on a patient with hemophilia B

The patient was an 80-year-old man with a history of factor IX deficiency and exertional chest pain. His factor IX deficiency was diagnosed 9 years ago when, at the age of 71 years, he was admitted to the hospital for treatment of a large hematoma of his right hip, sustained from a fall while working on his farm. His first significant bleeding episode was a syncopal event 53 years ago from a bleeding gastric ulcer, which resulted in a partial gastrectomy with a 26-unit blood transfusion. He had a 2-day bleeding episode 19 years ago after a tooth extraction and a left leg hematoma resulting from a fall 14 years ago. Two of his male cousins died of bleeding complications from tonsillectomies. During the evaluation of the hip hematoma 9 years ago, his prothrombin time was 11.7 seconds (normal values for the laboratory, 11.5 to 15.4 seconds), partial thromboplastin time was 38.5 seconds (normal values, 20 to 34 seconds), and platelet count was 250,000/pL. His factor IX level was 8% of normal at that time, and hemophilia B was diagnosed. He has had no evidence of a factor IX inhibitor. His present complaint of exertional chest pain prompted a cardiac evaluation. An exercise treadmill test was positive for ischemia, and subsequent coronary angiography showed an 80% occlusion of the proximal left anterior descending coronary artery, 90% occlusion of the first diagonal, 99% occlusion of the distal right coronary artery, and mild mitral valve regurgitation. His other medical problems included atrial fibrillation of a 10-year duration and benign prostatic hyperplasia. He was scheduled for elective coronary bypass surgery. At his preoperative evaluation, physical examination showed a I/VI systolic murmur near the apex consistent with mild mitral regurgitation and an irregularly irregular pulse at 72 to 80 beats/rain. Preoperative medications were digoxin and propranolol, mad his electrocardiogram showed atrial fibrillation.
The law of surrogate motherhood in the United States

The law of surrogate motherhood in the United States is in a state of flux and confusion. States have widely differing laws, some enforc ing surrogacy contracts, some banning them entirely, and some allowing them under certain circumstances. Many states have no laws regarding surrogacy contracts at all. No single statutory regime has won widespread acceptance. As a result, courts are often left to decide parenthood disputes arising from these contracts, and employ a range of theories by which to do so: intent, contract, genetics, gestation and, rarely, best interests of the child.
The Dinitramide Anion, N(NO2)2- ∇

The infrared and Raman spectra of the NH(4)(+), K(+), and Cs(+) salts of N(NO(2))(2)(-) in the solid state and in solution have been measured and are assigned with the help of ab initio calculations at the HF/6-31G and MP2/6-31+G levels of theory. In agreement with the variations observed in the crystal structures, the vibrational spectra of the N(NO(2))(2)(-) anion are also strongly influenced by the counterions and the physical state. Whereas the ab initio calculations for the free N(NO(2))(2)(-) ion indicate a minimum energy structure of C(2) symmetry, Raman polarization measurements on solutions of the N(NO(2))(2)(-) anion suggest point group C(1) (i.e., no symmetry). This is attributed to the very small (<3 kcal/mol) N-NO(2) rotational barrier in N(NO(2))(2)(-) which allows for easy deformation.
Cocrystals of Caffeine and Hydroxybenzoic Acids Composed of Multiple Supramolecular Heterosynthons: Screening via Solution-Mediated Phase Transformation and Structural Characterization

Caffeine, a pharmaceutical model compound, generally forms cocrystals with carboxylic acids that involve an O−H···N hydrogen bond between the carboxylic acid group of the acid and the caffeine imidazole moiety. Such solids are typically based on a single heterosynthon. To examine the facility of introducing additional supramolecular heterosynthons to the caffeine-carboxylic-acid cocrystal system, structural isomers of aromatic carboxylic acids (i.e., hydroxy- and dihydroxybenzoic acids) with additional hydrogen-bonding functional groups (i.e., hydroxy group) were screened for cocrystal formation. For this purpose, a highly efficient screening method based on thermodynamically driven solution-mediated phase transformation was utilized. This method enabled the rapid discovery of nine new solid phases involving caffeine. These caffeine phases were identified using single-crystal X-ray diffraction and FT-IR spectroscopy as cocrystals based on 2-, 3-, 4-hydroxybenzoic- and 2,3-, 2,4-, 2,5-, 3,4-, and 3,5-dihyd...
A fixed point for quantum gravity

Using the 1/N expansion a fixed point of the renormalization group is found for quantized gravitational theories which is non-trivial in all dimensions, d, including four. Using the fixed point it is shown how Einstein's theory can be renormalized for 3<d<4. In four dimensions the pure Einstein theory does not exist, but the R + Cμναβ2 theory does. It is shown how gravitational theories whose quantum lagrangians are scale invariant may be renormalized such that the scale invariance is broken only by the choice of the critical renormalization group trajectory. A comparison is made with the renormalization of four-fermion and Yukawa theories in 4−ϵ dimensions which suggests that quantum gravity might exist in four dimensions even if those theories do not.
Replication algorithms in a remote caching architecture

Studies the cache performance in a remote caching architecture. The authors develop a set of distributed object replication policies that are designed to implement different optimization goals. Each site is responsible for local cache decisions, and modifies cache contents in response to decisions made by other sites. The authors use the optimal and greedy policies as upper and lower bounds, respectively, for performance in this environment. Critical system parameters are identified, and their effect on system performance studied. Performance of the distributed algorithms is found to be close to optimal, while that of the greedy algorithms is far from optimal. >
Quantitative analysis of conjunctival goblet cells after chronic application of topical drops.

Introduction Chronic topical glaucoma therapy has been reported to cause deleterious changes to the ocular surface epithelial layers. We compare changes in the number of goblet cells after chronic exposure to latanoprost preserved with 0.02% benzalkonium chloride (BAK) eye drops (Xalatan®; Pfizer, NY, USA), travoprost preserved with sofZia® eye drops (Travatan Z®; Alcon, Fort Worth, TX, USA), or preservative-free artificial tears (Refresh Plus®; Allergan, Irvine, CA, USA).
Detection of speech tokens in noise using adaptive spectrotemporal receptive fields

Neurophysiological studies of sound encoding at the level of auditory cortex paint a picture of an intricate filterbank that encodes detailed spectral and temporal modulations in the sensory input. Furthermore, these filters exhibit adaptive qualities called neural plasticity that shape their tuning parameters in line with behavioral goals of interest. In this work, we explore qualitative principles about how this neuronal reshaping can aid in an enhanced representation of target sounds. Here, we employ a set of parameterized two-dimensional Gabor filters as basis functions that tile the space of neurophysiological spectrotemporal modulations. We examine mechanisms for judiciously retuning parameters of the Gabor filterbank in order to enhance the representation of target sounds of interest. We test the efficacy of this scheme in enhancing representation of sound tokens in adverse noisy backgrounds.
INTRODUCING TAYLOR POLYNOMIAL APPROXIMATIONS IN INTRODUCTORY CALCULUS

ABSTRACT The many advantages of presenting Taylor polynomial approximations as an immediate application of the derivative in Calculus I are discussed. A variety of student insights based on these notions are presented and a wide variety of applications and specific examples are shown.
Decreased estrogen binding in hormone-dependent mammary carcinoma following ovariectomy or dibutyryl cyclic amp treatment

Summary 7,12-Dimethylbenz( α )anthracene (DMBA)-induced mammary carcinomas regress after ovariectomy of the host or stop growing after treatment with N 6 , O 2 ′-dibutyryl-cyclic adenosine 3′,5′-monophosphate (DBcAMP). Six days after either treatment, estrogen binding of the tumor cytosol decreases to 50% of the growing control tumor cytosols. Neither the sedimentation profiles of the binding components seen on sucrose gradients nor the apparent binding affinity to estrogen ( K d ) is changed with the decrease of estrogen binding produced by either ovariectomy or DBcAMP treatment. These findings suggest that DBcAMP treatment mimics estrogen deprivation in the growth control of a hormone-dependent mammary tumor.
Evidence for Selective Differences between Cells with an Active Horse X Chromosome and Cells with an Active Donkey X Chromosome in the Female Mule

THE glucose-6-phosphate dehydrogenase (G6PD) locus is known to be X-linked in the horse and donkey1,2. The female mule, an interspecific hybrid of these two species, is an obligatory heterozygote for two electrophoretically distinguishable G6PD alleles1,2.
Highly conductive and transparent carbon nanotube composite thin films deposited on polyethylene terephthalate solution dipping

Abstract In this letter we present highly conductive and transparent thin films of single-walled carbon nanotubes (SWCNT) and conductive polymer composite deposited on polyethylene terephthalate film substrates by solution dipping. The initial results show that 66 Ω/⁪ sheet resistance can be achieved with 80% transmission at the wavelength of 550 nm. This result is much superior to the performances of the pure SWCNT thin films deposited using the same technique. The improvement is attributed to the increase of effective electric conductive tube–tube junctions in the CNT network.
Real-Time Dopamine Measurement in Awake Monkeys

Fast-scan cyclic voltammetry (FSCV) is often used to measure real-time dopamine (DA) concentrations in awake, behaving rodents. Extending this technique to work in monkeys would provide a platform for advanced behavioral studies and a primate model for preclinical research. The present study demonstrates the feasibility of DA recordings in two awake monkeys (Macaca mulatta) using a mixture of techniques adapted from rodent, primate and brain slice work. We developed a long carbon fiber electrode to operate in the larger primate brain. This electrode was lowered into the striatum each day using a recording chamber and a detachable micromanipulator system. A manipulator also moved one or more tungsten stimulating electrodes into either the nearby striatum or the ventral tegmental area/substantia nigra pars compacta (VTA/SNc). We developed an electrical stimulation controller to reduce artifacts during electrical stimulation. We also introduce a stimulation-based methodology for estimating distances between electrodes in the brain. Dopamine responses within the striatum were evoked by either stimulation of the striatum near the FSCV electrode, or stimulation within the VTA/SNc. Unexpected juice rewards also evoked dopamine responses in the ventral striatum. Thus, we demonstrate that robust dopamine responses can be recorded from awake, behaving primates with FSCV. In addition, we describe how a stimulation technique borrowed from the neuroprosthetics field can activate the distributed monkey midbrain dopamine system in a way that mimics rodent VTA stimulation.
Sufficient optimality conditions in continuous-time nonlinear programming

Abstract Various first-order sufficient optimality criteria for continuous-time nonlinear programming problems with nonlinear equality and inequality constraints are established under generalized convexity assumptions, and applications of these criteria to optimal control and continuous-time fractional programming problems are briefly discussed.
Effect of drug metabolism inducer and inhibitor on O,O,S-trimethyl phosphorothioate-induced delayed toxicity in rats

Abstract Oral administration of O,O,S-trimethyl phosphorothioate (OOS), an impurity present in widely used organophosphorus insecticides, causes delayed toxicity in rats, i.e., death occurring as late as 28 days after the treatment. The signs of toxicity include body weight loss (maximum on day 3), red staining around the nose, mouth and eyes, and an increased level of lactate dehydrogenase (LDH) in bronchopulmonary lavage fluid accompanied by morphological alteration of non-ciliated bronchiolar epithelial Clara cells. Pretreatment with phenobarbital, piperonyl butoxide (2 h), SKF 525-A, or small multiple doses of OOS protected against the OOS-induced elevated level of bronchopulmonary lavage LDH, and the other signs of delayed toxicity including morphological alteration of Clara cells. These studies support the view that OOS-induced delayed toxicity is mediated by the cytochrome P-450 dependent metabolism of OOS, and the lung may be the major target organ of delayed toxicity produced by OOS.
A microsystem for sensing and patterning oxidative microgradients during cell culture

We present the design, modeling, fabrication and testing of a microsystem for the electrolytic patterning and sensing of oxidative microgradients within 1 × 1 mm2 area during cell culture. The system employs an array of microfabricated electrodes (3–40 µm in width) embedded in gas-permeable microchannels to generate precise doses of dissolved oxygen (ranging from 10 fmol O2 mm−2 s−1 to 100 nmol O2 mm−2 s−1) via electrolysis. The microgradients generated by different microelectrodes in the array can be superimposed to pattern multi-dimensional oxygen profiles not possible with other methods. We demonstrate the patterning, sensing and quantification of dissolved oxygen microgradients in the 0 to 40% dO2 range using this microsystem. Reactive oxygen species generation and dosing is also quantified. Lastly, we demonstrate how the microtechnology enables new types of experiments in three different cell culture models: localized hyperoxia-induced apoptosis in C2C12 myoblasts, dynamic aerotaxis assays of Bacillus subtilis, and studies of calcium release in an ischemia/re-oxygenation myoblast model.
Exposure of human proximal tubule cells to cytotoxic levels of CdCl2 induces the additional expression of metallothionein 1A mRNA

Humans, in contrast to animals, have a complex expression of metallothionein (MT) genes which involves many MT isoforms encoded by a family of genes containing an upper limit of 12 possible functional genes. It is unknown if these human isoforms of MT have distinct functions or if they simply represent a non-essential duplication of gene function. In the present study, MT protein and mRNA for the MT-2A, MT-1A, B, E, F, and G genes was determined for 3 isolates of human proximal tubule (HPT) cells having distinct sensitivities to cadmium. For all 3 HPT isolates, the expression of MT protein and mRNA for the MT-2A, MT-1E, MT-1F and MT-1G isoforms was similar among the isolates and demonstrated no correlation to lethality. However, each isoform mRNA was expressed at different levels when compared to one another. In contrast, the expression of MT-1A mRNA differed in expression and correlated with the differing lethalities displayed by each isolate. The finding of different profiles of mRNA expression provides evidence that the MT isoforms may have unique functions and that mRNA for the MT-1A gene could be a potential marker for heavy metal exposure and/or toxicity.
Absolute-reaction-rate theory of vacancy diffusion and of interface reaction in face-centered cubic solid solutions

Abstract The absolute-reaction-rate theory has been made more useful for treating diffusion in metals by applying it to a single configuration of the atom-vacancy pair involved in the jumping process. The configuration in question is that of the first coordination shell surrounding the atom and the one surround ing the vacancy also. The application to tracer diffusion in a pure component is illustrated. Before treating interface reactions by a similar theory, it is shown how vacancies can be considered to be the particles of a “void component” and how the “void phase” can be made thermodynamically unstable. A configurational theory is then presented for the simple case of the interface reaction that occurs as part of the total transport process of diffusion and interface reaction in a two-phase system.
Control of a combined GTO/IGBT drive system for low torque ripple in a large permanent magnet synchronous motor

A control method is developed for a drive system, built of a parallel interconnection of a high-power GTO and a low-power fast-switching IGBT, feeding a large permanent magnet synchronous motor (PMSM) where torque ripple attenuation is a primary concern. The GTO is the main power supply and the IGBT is used for attenuating the current ripple due to the GTOs low switching frequency. The proposed controller combines a hierarchical, passivity-based dynamic feedback compensator, guaranteeing global exponential stability, as a well as a space vector PWM (SVM) strategy, that prevents stray, zero-sequence currents. The prevention of substantial stray currents between inverters is essential for the successful implementation of the proposed topology and is addressed by the combination of the master-slave compensator structure with the matching SVM strategy.
Calcium, magnesium and the control of PTH secretion

Abstract Critical to the regulation of mineral ion homeostasis is the inverse relationship bewtween the extracellular calcium (Ca2+) concentration and PTH secretion (Fig. 1). Early studies in vivo [1] and in vitro [2] demonstrated that high magnesium (Mg2+) concentrations also inhibit PTH release. At low concentrations, on the other hand, the effects of Ca2+ and Mg2+ on PTH secretion differ: while hormonal secretion persists for an hour or more even at vanishingly low Ca2+ concentrations [3,4], Connie Anast and his co-workers were the first to demonstrate that low Mg2+ concentrations inhibit PTH secretion [5]. In these classical studies, Dr Anast was able to use detailed clinical observations in a single patient to draw important pathophysiological conclusions. Indeed, in the ensuing years, only limited progress has been made in extending these observations to elucidate the cellular mechanisms underlying the inhibition of PTH release at low Mg2+. Considerable advances, on the other hand, have been made in understanding the control of PTH release by high Ca2+ and Mg2+ concentrations. These studies will be reviewed here and provide, in turn, a conceptual framework within which to consider the effects of low Mg2+ on PTH secretion.
Libya and American war powers: war-making decisions in the United States

During the United States' military strikes in Libya in 2011, the debate over the authority to use force reached levels not experienced in recent American history. Many members of Congress, both Democrat and Republican, expressed concern over what they viewed as a usurpation of Congress's constitutional war powers. These concerns were exacerbated when the Obama administration maintained that it was not engaged in ‘hostilities’ and that the War Powers Resolution, which was intended to limit the president's war authority, did not apply to this use of force. Yet despite the strong levels of bipartisan constitutional pressure waged against the commander in chief, these efforts were generally discouraged, co-opted or simply opposed by the House and Senate leadership. This research examines the role of Congress's institutional and party leaders, specifically Speaker of the House John Boehner (R-OH), and Senators John Kerry (D-MA) and John McCain (R-AZ), and finds that their leadership was instrumental in keeping...
dSarm-ing Axon Degeneration

Plucked from the tree, a leaf withers. Such a loss of vitality upon removal from the whole appears so natural that one may take it for granted as a passive and unstoppable process. But is it? Although cell death was long thought to be a passive process, we now know that at least one form of cell death, apoptosis (from Greek “falling away”), is an active process that can be blocked by inhibiting a specific signaling pathway ( 1 ). On page 481 of this issue, Osterloh et al. ( 2 ) find that the death of a portion of a nerve cell, the axon, after it is severed from the cell body, can be dramatically slowed by the inactivation of just one gene. The discovery has important implications for understanding the molecular mechanisms of axon degeneration, as well as for developing drugs against neurodegenerative diseases.
Reactions of ruthenium(II) tris(pyrazolyl)borate and tris(pyrazolyl)methane complexes with diphenylvinylphosphine and 3,4-dimethyl-1-phenylphosphole

Abstract Several new ruthenium(II) tris(pyrazolyl)borate and tris(pyrazolyl)methane complexes containing diphenylvinylphosphine (DPVP), 3,4-dimethyl-1-phenylphosphole (DMPP) and 1,2-bis (diphenylphosphino) ethane (dppe), namely: (Tp)Ru (DPVP) (CH3CN)Cl; (Tp)Ru (DPVP)2Cl; (Tp)Ru (DPVP) (DMPP) [4+2]Cl; [(Tp)Ru (DPVP)2 (CH3CN)]PF6; (Tp)Ru (DMPP)2 [4+2]Cl; [(Tpm)Ru (DPVP)2 Cl]PF6; [(Tpm)Ru(dppe)Cl]PF6; [(Tpm)Ru(DMPP)2 [4+2]Cl]PF6 and [(Tp)Ru (dppe) (Me2CO)]PF6 have been prepared, characterized and their reaction chemistry studied. Characterization includes infrared spectroscopy, 1H-, 13C{1H}- and 31P{1H}-NMR spectroscopy and in several cases X-ray crystallography.
Total Synthesis of 3,6‐Dimethoxy‐17β‐Acetyl‐1,3,5(10),6,8‐Estrapentaene

A Friedel-Crafts reaction of 2,8-dimethoxynaphthalene with β-methyltricarballylic acid anhydride (I) gave the ketoacid (IId), which upon catalytic hydrogenation and cyclization with hydrogen fluoride afforded the tricyclic ketone (V). Addition of methyl acrylate yielded the tetracyclic ester (VI), which was dehydrated and then decarboxylated at carbon 15. The reactions could be controlled to produce either the 17α- or the 17β epimers (IX) and (X). Their hydrogenation furnished the 14β, 17α- and 14α, 17β isomers (XII) and (XIb), respectively. The latter was transformed into the 17β-acetyl derivative (XIe).
Family Transitions In Young Adulthood

Using the first (1995) and third (2001–2002) waves of the Add Health survey, we examine women’s family transitions up to age 24. Only a third of all women marry, and a fifth of those marriages dissolve before age 24. Three out of eight women have a first birth, with a substantial majority of those births outside of marriage: 66% for whites, 96% for blacks, and 72% for Mexican Americans. Cohabitation is the predominant union form; 59% of women cohabit at least once by age 24. Most cohabitations are short lived, with approximately one in five resulting in a marriage. We summarize the family and relationship experience of women up to age 24 in terms of four categories, each accounting for roughly a quarter of all women. Category 1 has the women who remain single nonparents. Category 2 has the early marriers, women whose marriage is not preceded by a first birth. Category 3 has those who become single parents. Category 4 has the women who cohabit at least once, but who do not marry or have a birth by age 24. The strictly ordered transitions of the 1950s are long gone and have been replaced by a variety of paths to adulthood.
An evaluation of monitoring methods for the endangered giant kangaroo rat

Accurate, reliable, and efficient monitoring methods for detecting changes in the distribution and abundance of wildlife populations are the cornerstone of effective management. Aerial surveys of active burrow sites and ground counts of open burrows have been used to estimate distribution and abundance, respectively, of a number of rodent species. We compared the efficacy of these and other methods for estimating distribution, abundance, and population growth of the endangered giant kangaroo rat (Dipodomys ingens) to determine the best practices for monitoring. Specifically, we compared aerial surveys, rapid expert assessments, and live-trapping for estimating giant kangaroo rat range, and burrow counts and live-trapping for estimating abundance and growth. We carried out the study in the Carrizo Plain National Monument, California, USA, from 2007 to 2011. Expert rapid assessment of sites performed nearly as well as trapping in determining range extent, while aerial surveys provided estimates of total range extent but with less precision. Active burrow counts were adequate to determine relative abundance averaged over multiple years, but were not reliable as an estimate of annual population size or growth. © 2012 The Wildlife Society.
Totally nonnegative moment matrices

Abstract The finite dimensional moment matrices of distributions which are either concentrated on the nonnegative half line or symmetric around zero are similar to totally nonnegative matrices. An analogous result holds true for Schur complements in these moment matrices. As a consequence, in the former case the nonzero eigenvalues of these matrices have multiplicity one, and in the latter at most two. This is a key result for finding E -optimal polynomial regression designs in Heiligers (1992); see also Pukelsheim and Studden (1993).
Chemical, quasi‐chemical and perturbation theories for associating fluids

Pure fluids and mixtures of species that hydrogen bond behave differently from systems that interact only through dispersion forces. The deviations from classical behavior often are sufficiently large that conventional equations of state and activity models cannot be used without the introduction of large, condition-dependent empirical parameters. Consequently, three different classes of theories have been developed specifically to treat hydrogen-bonding systems. The first is based on the assumption that when molecules hydrogen-bond, they react to form new species and consequently is referred to as “chemical” theory. The second is based on lattice-fluid theory that is used to describe different types of specific interactions and is known as “quasi-chemical” theory. The last is based on the solution of integral equations using a potential function that mimics that of a hydrogen bond. It is shown here that these three approaches give essentially equivalent results. This allows one to relate the parameters in the perturbation theory to the equilibrium constant and hence greatly improves its utility for real systems. All three theories are compared with simulation data.
Development and evaluation of a 24 well microtitre plate method for isolation of Listeria spp. or Listeria monocytogenes from foods

A rapid and simple method (24M) using 24 well microtitre plates was developed to determine the presence of Listeria monocytogenes or Listeria spp. in food samples. The 24M was composed of two 24 well microtitre plates connected with a yellow tip. The 24M was evaluated with pathogen cocktails and ground beef samples and compared with the conventional method for presumptive identification of Listeria spp. Only food-borne pathogen cocktails and ground beef samples containing L. monocytogenes or Listeria spp. showed a positive reaction in 24M after 24 h incubation at 35 degrees C. Test results were the same with the conventional method and the 24M method and showed high efficiency for recovery of Listeria spp. from foods. This new, convenient and economical method can isolate Listeria spp. simultaneously from 24 different food samples.
On the cooling of ascending andesitic magma.

In ascending through the lithosphere, andesitic magma probably cools by about 300 K. Since the ascent velocity and dynamics of ascent are unknown, several different phenomenological cooling models are considered to account for this temperature decrease. These results are compared to the phase relations of andesitic magma in order to estimate an ascent velocity which can be used to investigate a dynamic model of ascent. The cooling models approximate an initially crystal-free magma ascending by elastic crack propagation (plate model), viscous blobs (spherical model), and by flow up a pipe. It is shown that heat transfer is predominantly by convection and conduction, and that an adiabatic ascent is unlikely. The calculated cooling curves have the general shape of the geotherm and are concave to the liquidus and solidus of the magma. Hence the magma is likely to become superheated over much of its ascent which precludes crystal fractionation, and the petrology of the lavas seems to support this. For a viscous sphere of magma the ascent velocity must be greater than about 10$^{-7}$ m s$^{-1}$, but for a crack of the same volume, because of its large surface area, ascent is at least 10$^{-3}$ m s$^{-1}$. Because of the paucity of mantle xenoliths in andesitic lavas, this latter ascent velocity seems unlikely.