cssi/SciSciGPT-SciSciNet huggingface dataset:
A Mathematical Theory of the Functional Dynamics of Cortical and Thalamic Nervous Tissue

It is proposed that distinct anatomical regions of cerebral cortex and of thalamic nuclei are functionally two-dimensional. On this view, the third (radial) dimension of cortical and thalamic structures is associated with a redundancy of circuits and functions so that reliable signal processing obtains in the presence of noisy or ambiguous stimuli. A mathematical model of simple cortical and thalamic nervous tissue is consequently developed, comprising two types of neurons (excitatory and inhibitory), homogeneously distributed in planar sheets, and interacting by way of recurrent lateral connexions. Following a discussion of certain anatomical and physiological restrictions on such interactions, numerical solutions of the relevant non-linear integro-differential equations are obtained. The results fall conveniently into three categories, each of which is postulated to correspond to a distinct type of tissue: sensory neo-cortex, archior prefrontal cortex, and thalamus. The different categories of solution are referred to as dynamical modes. The mode appropriate to thalamus involves a variety of non-linear oscillatory phenomena. That appropriate to archior prefrontal cortex is defined by the existence of spatially inhomogeneous stable steady states which retain contour information about prior stimuli. Finally, the mode appropriate to sensory neo-cortex involves active transient responses. It is shown that this particular mode reproduces some of the phenomenology of visual psychophysics, including spatial modulation transfer function determinations, certain metacontrast effects, and the spatial hysteresis phenomenon found in stereopsis.
A tale of three genomes: the kinetoplastids have arrived

July 2005 marked a milestone in kinetoplastid biology research. A tour de force effort led by the Tri-Trypanosomatidae ‘Tritryp' genome consortium yielded the publication of three prominent kinetoplastid parasite genome sequences: Trypanosoma brucei , Trypanosoma cruzi and Leishmania major . The individual and combined comparative analyses of these three genome sequences, combined with proteomic analyses, have yielded insights into topics ranging from genome evolution and horizontal gene transfer to potential new therapeutic and vaccine targets.
Computational study on the effects of annealing on the mechanical properties of polycrystalline graphene

The feasibility of mass production of polycrystalline graphene (polygraphene) has motivated intensive efforts to boost its promising applications in electronics, energy storage, composites and biomedicine. As the grain boundaries in graphene-related 2D materials can strongly affect their material properties and the performance of graphene-based devices, it is highly desirable to better understand the effects of grain boundaries and make them as stable as possible. Here we employ molecular dynamics simulation to explore the annealing process of polygraphene and compare mechanical properties of annealed and unannealed polygraphene to pristine graphene under the same conditions, with a focus on the stability and energy of the grain boundaries. It is shown that the annealing process has a strong effect on the strength and stiffness of polygraphene due to the rearrangement and stabilization of the grain boundaries. However, our results show that irrespective of grain size, the annealing process makes polygraphene both tougher and stiffer, with a higher Young’s modulus, strength, and ultimate strain under a tensile test compared to the same samples prior to the annealing process.
List Discrimination in Associative Recognition and Implications for Representation.

Four experiments tested the predictions made by the model outlined in A. H. Criss and R. M. Shiffrin (2004b). Participants studied 2 successive lists of pairs followed by a recognition memory test for the most recent list. Some items and some pairs were repeated across the 2 lists. Critically, a given item could be repeated in the same or different type of pair. For associative recognition, performance was only affected by repetitions in the same pair type. However, in single-item recognition confusions occurred for both types of repetitions. The results are as predicted and confirm the assumption that different associative representations were stored even when the same token repeated in different pair types, whereas similar item representations were used regardless of pair type.
Understanding And Misunderstanding In Cross-Cultural Practice: Further Conversations With Suwanrang

Understanding is an essential clinical practice skill, one which draws upon cognitive and affective, conscious and unconscious abilities. This paper explores the challenges posed by cross-cultural understanding. Using concepts from anthropology and data from anthropological field work and clinical practice, it examines cultural differences in the experience and communication of affect. Clinical examples from Northern Thailand are used to illustrate the ways these subtle and complex differences in clients’ affective worlds challenge our capacity to understand those who are culturally different. Implications for cross-cultural social work practice are addressed.
Effect of Lead on Hepatic δ‐Aminolaevulinic Acid Synthetase Activity in the Rat: A Model for Drug Sensitivity in Intermittent Acute Porphyria*

The hereditary hepatic porphyrias are disorders of porphyrin and haem synthesis characterized by a marked idiosyncrasy towards a variety of lipid soluble drugs. Most of these agents are inducers of the haemoprotein cytochrome P450, the terminal oxidase in drug metabolism. The primary genetic defect in intermittent acute porphyria is a partial deficiency of uroporphyrinogen I synthetase, which may result in a secondary derepression of delta-aminoaevulinic acid synthetase, the rate-limiting enzyme in the haem pathway. Analogous defects at more distant sites may explain the other hereditary hepatic porphyrias. As drug sensitivity may be related to the defect in haem synthesis, we investigated the effects of experimental partial blocks in haem synthesis produced by lead in rats. Drug effects on delta-aminolaevulinic acid synthetase, cytochrome P450, And drug metabolism were studied. Our findings indicate: a) While partial impairment of haem biosynthesis has only minor effects on delta-aminolaevulinic acid synthetase activity, it greatly enhances the sensitivity of delta-aminolaevulinic acid synthetase to induction by drugs and steroids, which when given alone, have little or no inducing effect on the enzyme. b) The experimental partial block in haem synthesis delays and impairs drug-mediated induction cytochrome P450 and drug metabolism in vitro. The findings may explain why a large number of structurally unrelated compounds with little effect on normal liver can precipitate "aucte porphyria".
A radioisotope generator of indium-113m

Abstract A method is presented for making a generator system for routinely eluting the 1.7 hr half-life nuclide indium-113 m from its 118 day half-life parent tin-113. This utilizes the ion exchange properties of hydrous zirconium oxide crystals. The tin is loaded on the column in 0.3–0.5 N HCl solution and indium activity is eluted out with 0.1 N HNO 3 or 0.1 N HCl. Leakage of tin-113 when eluted every day for a period of 45 days was found to be always of the order of 10 −5 to 10 −6 times the original activity and the yield of indium-113m ranged from 70–80 percent of residual tin activity. The radiochemical impurities antimony-125 and tellurium-125 m present in tin-113 preparations are also removed by this method. Indium-113 m obtained by this method should find numerous applications in nuclear medicine.
Tipping the Scale Heart Failure, Body Mass Index, and Prognosis

Obesity has reached endemic proportions. The World Health Organization has estimated that >1 billion adults are overweight worldwide, and 300 million of them are clinically obese.1 In the general population up to 60 to 65 years of age, a higher body mass index (BMI) is associated with an increased risk for cardiovascular events and new-onset heart failure (HF). An increasing number of patients with chronic illness are obese. Of patients with chronic HF, >50% are in the overweight or obese categories.2 Although it was presumed that obesity would further increase mortality risk in patients with established HF, a number of recent studies have indicated that BMI is actually inversely associated with long-term mortality in chronic HF, the so-called obesity paradox.3 Article p 627 In this issue of Circulation , a retrospective analysis of the Candesartan in Heart Failure: Assessment of Reduction in Mortality and Morbidity (CHARM) trial program by Kenchaiah et al4 on the relationship between BMI and survival and other important clinical end points is reported. The authors analyzed data from all 7599 patients with symptomatic chronic HF who received candesartan (n=3803) or placebo (n=3796) and who were either angiotensin-converting enzyme inhibitor naive or already treated with such a drug. Patients were in New York Heart Association classes II through IV, and their left ventricular ejection fractions were distributed across a wide range, with a mean value of 39%. All subjects were followed up for a median of 37.7 months. Kenchaiah et al subgrouped the patients according to different BMI categories, with those with a BMI between 30.0 and 34.9 kg/m2 serving as the reference group because these patients had the overall lowest mortality. This is an important qualitative difference from most other articles on the …
Geographic and temporal development of plagues

ALTHOUGH deterministic and stochastic descriptions of localised epidemics abound in the literature of epidemiology and quantitative biology1,2, the geographic spread of epidemics has not been analyzed in such detail. (Although in ref. 2, page 205, Bailey gives equations similar in spirit to my equation (1) they seem to lack physical significance.) Realistic mathematical models of the geotemporal development of plagues could be useful in the study of epizootics (that is, in ecology, wildlife management or veterinary medicine), of social phenomena (such as the spread of drug abuse or fads), and of history. Needless to say, such models should also be applicable to public health questions.
Damped-driven granular chains: an ideal playground for dark breathers and multibreathers.

By applying an out-of-phase actuation at the boundaries of a uniform chain of granular particles, we demonstrate experimentally that time-periodic and spatially localized structures with a nonzero background (so-called dark breathers) emerge for a wide range of parameter values and initial conditions. We demonstrate a remarkable control over the number of breathers within the multibreather pattern that can be “dialed in” by varying the frequency or amplitude of the actuation. The values of the frequency (or amplitude) where the transition between different multibreather states occurs are predicted accurately by the proposed theoretical model, which is numerically shown to support exact dark breather and multibreather solutions. Moreover, we visualize detailed temporal and spatial profiles of breathers and, especially, of multibreathers using a full-field probing technology and enable a systematic favorable comparison among theory, computation, and experiments. A detailed bifurcation analysis reveals that the dark and multibreather families are connected in a “snaking” pattern, providing a roadmap for the identification of such fundamental states and their bistability in the laboratory.
Current-voltage behavior of 2D granular NbN films

Abstract We have measured the I–V characteristics of 2D granular NbN near the superconducting topological transition temperature, T 2D . Characteristic changes in the I–V curves occur at T 2D and the shape of the I–V curve at T 2D is consistent with theoretical predictions. These results lend additional support to the vortex-antivortex model for the 2D topological transition, but suggest refinements in the theory to incorporate the granular nature of the films will be needed for quantitative agreement.
Delayed Clamping of the Umbilical Cord: A Review With Implications for Practice

S.N., a healthy 22-year-old gravida 2 para 1 at 38 2/7 weeks’ gestation, was admitted to the hospital in active labor. Her history and prenatal course were uncomplicated. Contractions began 10 hours before her arrival at the hospital. Her vaginal examination on arrival was 5 cm dilatation, 50% effaced, and –2 station of the vertex, with intact membranes. Her contractions were occurring every 3 to 5 minutes. Shortly after hospital admission, epidural analgesia was initiated at the patient’s request. Four hours later, the frequency of her contractions was every 4 to 6 minutes, and a pelvic examination revealed minimal progress at 6 cm dilatation, 80% effacement, and –1 station. In an attempt to increase the frequency of her contractions, an amniotomy was performed and oxytocin augmentation was initiated. An hour later, her contractions were occurring every 3 to 4 minutes, lasting 60 to 90 seconds. Three hours later, she was fully dilated and the baby’s head was at +1 station in an occiput anterior position. At this point, she was instructed to begin pushing with each contraction. Twenty minutes later, S.N. gave birth via normal spontaneous vaginal delivery to a healthy baby boy. The umbilical cord was clamped within 30 seconds of birth, which is routine practice at this hospital, and the baby was brought directly to the warmer. There was no previous discussion with S.N. concerning the timing of the umbilical cord clamping. The placenta spontaneously delivered 5 minutes later, at which point routine oxytocin infusion was initiated via intravenous infusion. The baby boy weighed 3075 g and had Apgar scores of 9 and 9, at 1 and 5 minutes, respectively. There were no labial or perineal lacerations, nor excessive bleeding. The mother’s blood type was Rh-positive. Breastfeeding was not attempted in the immediate postpartum period because of maternal exhaustion. Postpartum day one, the baby was both bottle-feeding with formula and breastfeeding. The baby’s newborn examination and laboratory values were within normal limits. The family left the hospital on the second postpartum day, satisfied and doing well.
AC Dielectric Performance of Helium Impregnated Multi-Layer Plastic Film Insulation

Several types of thin polymer film insulation are being evaluated for possible use in superconducting underground transmission cables. Measurements are reported on the partial discharge inception voltages of threelayer disc samples of 102-?m polyethylene and 61-?m polycarbonate for temperatures and pressures of the helium impregnant ranging from 5.0 K and 0.3 MPa to 11.5 K and 1.5 MPa. Butt gaps are simulated by punching 1 mm diameter holes in some of the layers. The effect of aluminized shielding around the holes is discussed. The observed inception voltages vary strongly with the helium conditions, increasing rapidly as the density increases. The results suggest that the voltage is capacitively divided between the polymer layers and helium-filled gaps, with partial discharge occurring when the breakdown strength of the helium is exceeded.
Late Presentation of Cryptorchidism: The Etiology of Testicular Re-Ascent

AbstractPurpose: We reviewed the records of 21 boys who had 23 previously documented descended testes that reascended and who underwent orchiopexy during a 2-year period.Materials and Methods: We retrospectively reviewed a 2-year experience in 103 boys (115 undescended testes) who underwent orchiopexy in 1988 and 1989.Results: In our 2-year experience 21 of the 103 boys with undescended testes had multiple recorded confirmations of testicular descent in the past. Of the boys 40% had previously been examined in the office or with general anesthesia by a pediatric urologist or pediatric surgeon for another reason, and 40% had a nurse or physician parent. Surgery was performed at ages 5 to 14 years, an average of 2 years after the initial presentation with reascent. Human chorionic gonadotropin was unsuccessful in causing testicular descent. There was no correlation with a patent processus vaginalis and no association with adhesions. The testis was located in the superficial inguinal pouch in the majority of...
Late Holocene hydrous mafic magmatism at the Paint Pot Crater and Callahan flows, Medicine Lake Volcano, N. California and the influence of H2O in the generation of silicic magmas

This paper characterizes late Holocene basalts and basaltic andesites at Medicine Lake volcano that contain high pre-eruptive H2O contents inherited from a subduction related hydrous component in the mantle. The basaltic andesite of Paint Pot Crater and the compositionally zoned basaltic to andesitic lavas of the Callahan flow erupted approximately 1000 14C years Before Present (14C years b.p.). Petrologic, geochemical and isotopic evidence indicates that this late Holocene mafic magmatism was characterized by H2O contents of 3 to 6 wt% H2O and elevated abundances of large ion lithophile elements (LILE). These hydrous mafic inputs contrast with the preceding episodes of mafic magmatism (from 10,600 to ∼3000 14C years b.p.) that was characterized by the eruption of primitive high alumina olivine tholeiite (HAOT) with low H2O (<0.2 wt%), lower LILE abundance and different isotopic characteristics. Thus, the mantle-derived inputs into the Medicine Lake system have not always been low H2O, primitive HAOT, but have alternated between HAOT and hydrous subduction related, calc-alkaline basalt. This influx of hydrous mafic magma coincides temporally and spatially with rhyolite eruption at Glass Mountain and Little Glass Mountain. The rhyolites contain quenched magmatic inclusions similar in character to the mafic lavas at Callahan and Paint Pot Crater. The influence of H2O on fractional crystallization of hydrous mafic magma and melting of pre-existing granite crust beneath the volcano combined to produce the rhyolite. Fractionation under hydrous conditions at upper crustal pressures leads to the early crystallization of Fe-Mg silicates and the suppression of plagioclase as an early crystallizing phase. In addition, H2O lowers the saturation temperature of Fe and Mg silicates, and brings the temperature of oxide crystallization closer to the liquidus. These combined effects generate SiO2-enrichment that leads to rhyodacitic differentiated lavas. In contrast, low H2O HAOT magmas at Medicine Lake differentiate to iron-rich basaltic liquids. When these Fe-enriched basalts mix with melted granitic crust, the result is an andesitic magma. Since mid-Holocene time, mafic volcanism has been dominated primarily by hydrous basaltic andesite and andesite at Medicine Lake Volcano. However, during the late Holocene, H2O-poor mafic magmas continued to be erupted along with hydrous mafic magmas, although in significantly smaller volumes.
THE GODDESS AND THE NATION: Mapping Mother India. By Sumathi Ramaswamy

(2012). The Goddess And The Nation: Mapping Mother India. By Sumathi Ramaswamy. Geographical Review: Vol. 102, No. 1, pp. 135-137.
Autodigestion and RecA-dependent cleavage of Ind- mutant LexA proteins.

The LexA repressor of Escherichia coli undergoes a specific cleavage reaction in vivo, an event that leads to derepression of the SOS regulon and requires an activated form of RecA protein. In vitro, cleavage requires RecA at neutral pH; at alkaline pH, a spontaneous cleavage reaction termed autodigestion takes place. Both autodigestion and RecA-mediated cleavage cut the same bond, and are observed for the same set of substrates, suggesting that RecA acts indirectly to stimulate LexA self-cleavage at neutral pH, perhaps binding to LexA and acting as an allosteric effector. We previously isolated a set of lexA(Ind−) mutants that are deficient in in vivo RecA-mediated cleavage but retain significant repressor function. Here, we describe the in vitro cleavage of purified mutant proteins. All of those tested were deficient in both cleavage reactions. Although most of them were equally deficient in both reactions, some were more deficient in one reaction than the other. Several mutant proteins appeared to have defects in binding to RecA. Autodigestion of all but one of the poorly cleavable mutant proteins reached a maximum rate at pH around 10, as does wild-type LexA. The exception was KR156, which changed Lys156, a residue previously implicated in the mechanism of cleavage, to Arg, another basic residue; for this protein, the rate of autodigestion increased with pH at values above 11. RecA-mediated cleavage of KR156 was 1% the wild-type rate at pH 7, but increased with increasing pH to a plateau at pH 9.5, where the rate was 40% the wild-type rate. In contrast, an essentially constant rate was observed for wild-type LexA over the pH range 6 to 11. We suggest, first, that deprotonation of Arg156 and, by inference, Lys156 in the wild-type protein, is required for both autodigestion and RecA-mediated cleavage; and second, that RecA acts to reduce the pKa of Lys156, allowing efficient cleavage of wild-type repressor under physiological conditions.
THE REMOVAL OF CARTILAGE MATRIX, IN VIVO, BY PAPAIN : IDENTIFICATION OF CRYSTALLINE PAPAIN PROTEASE AS THE CAUSE OF THE PHENOMENON

The intravenous injection of crystalline papain into young rabbits results in depletion of cartilage matrix throughout the body, with loss of rigidity and collapse of the ears, provided the enzyme is inactivated by oxidation or sulfhydryl blocking agents prior to administration. Cysteine-activated crystalline papain, when injected intravenously, produces little or no change in cartilage. The changes which occur in cartilage following an injection of inactivated crystalline papain are indistinguishable from those produced by crude papain. Activation of crude papain by cysteine prior to injection results in loss of its capacity to produce in vivo changes in cartilage. The progressive changes which take place in cartilage in vivo also occur in vitro in isolated rabbit ears removed shortly after an injection of crude papain or inactivated crystalline papain. In vitro ear collapse occurs rapidly at 37°C. and does not occur at 4°C. Collapse is enhanced by exposing the cartilage to cysteine and prevented by exposure to iodoacetamide or p-chloromercuribenzoate. The direct action of crystalline papain on plates of normal cartilage, in vitro, results in the same gross and histological changes which were observed in vivo. The direct action is accelerated by cysteine and inhibited by iodoacetamide or p-chloromercuribenzoate. The intravenous injection of iodoacetamide-treated bromelin produces the same in vivo changes in cartilage as papain. Untreated bromelin has no demonstrable effect on cartilage. It is suggested that the reason for the failure of activated papain to enter cartilage, after being injected intravenously, is that it probably reacts with a substrate or substrates in the blood. Oxidized or otherwise inactivated papain, in contrast, is readily taken up by cartilage and there converted to its active form.
Hyperspectral Aquatic Radiative Transfer Modeling Using a High-Performance Cluster Computing-Based Approach

For aquatic studies, radiative transfer (RT) modeling can be used to compute hyperspectral above-surface remote sensing reflectance that can be utilized for inverse model development. Inverse models can provide bathymetry and inherent-and bottom-optical property estimation. Because measured oceanic field/organic datasets are often spatio-temporally sparse, synthetic data generation is useful in yielding sufficiently large datasets for inversion model development; however, these forward-modeled data are computationally expensive and time-consuming to generate. This study establishes the magnitude of wall-clock-time savings achieved for performing large, aquatic RT batch-runs using parallel computing versus a sequential approach. Given 2,600 simulations and identical compute-node characteristics, sequential architecture required ~100 hours until termination, whereas a parallel approach required only ~2.5 hours (42 compute nodes)—a 40x speed-up. Tools developed for this parallel execution are discussed.
Preparation, functional characterization, and NMR studies of human KCNE1, a voltage-gated potassium channel accessory subunit associated with deafness and long QT syndrome.

KCNE1, also known as minK, is a member of the KCNE family of membrane proteins that modulate the function of KCNQ1 and certain other voltage-gated potassium channels (KV). Mutations in human KCNE1 cause congenital deafness and congenital long QT syndrome, an inherited predisposition to potentially life-threatening cardiac arrhythmias. Although its modulation of KCNQ1 function has been extensively characterized, many questions remain regarding KCNE1's structure and location within the channel complex. In this study, KCNE1 was overexpressed in Escherichia coli and purified. Micellar solutions of the protein were then microinjected into Xenopus oocytes expressing KCNQ1 channels, followed by electrophysiological recordings aimed at testing whether recombinant KCNE1 can co-assemble with the channel. Nativelike modulation of channel properties was observed following injection of KCNE1 in lyso-myristoylphosphatidylglycerol (LMPG) micelles, indicating that KCNE1 is not irreversibly misfolded and that LMPG is able...
Identification of a pathogenicity island required for Salmonella enteropathogenicity.

Summary Salmonella spp. interact with ileal mucosa and disrupt normal intestinal function, which results in an acute inflammatory cell influx, fluid secretion and enteritis. We have recently characterized SopB, a novel secreted effector protein of Salmonella dublin, and presented evidence that SopB is translocated into eukaryotic cells via a sip-dependent pathway to promote fluid secretion and inflammatory responses. Here, we show that sopB is located on a large DNA fragment unique to the Salmonella chromosome. This locus is conserved in Salmonella and maps at approximately 20 centisome of the S. typhimurium chromosome. Sequence analysis revealed that this Salmonella-specific DNA fragment is flanked by DNA sequences with significant sequence similarity to the Escherichia coli K-12 genes, tRNA1 Ser (serT ) on one side and copS/copR on the other. Thus, this Salmonella-specific DNA fragment has features characteristic of ‘pathogenicity islands’ and, therefore, it was denoted SPI-5 (Salmonella pathogenicity island-5). SPI-5 was sequenced and was found to contain five novel genes, pipA, pipB, pipC, pipD (pathogenicity island-encoded proteins) and orfX, in addition to sopB. The effect of mutations in pipA, pipB and pipD on the induction of fluid secretion and an acute inflammatory cell influx was assessed in bovine ligated ileal loops. The effect of mutations in SPI-5-encoded genes on systemic salmonellosis was assessed in mice. The results of these experiments suggest that SPI-5-encoded genes contribute to enteric but not to systemic salmonellosis.
Pharmacokinetics of Cephradine Suspension in Infants and Children

The pharmacokinetics of cephradine suspension were studied in 16 infants and children who were 13 months to 8 years and 3 months of age (means age, 3.5 years). Mean peak concentrations of 21.3 and 9.9 μg/ml were achieved at 30 min after administration of 60-mg/kg doses to fasting and nonfasting patients. The area under the serum concentration-time curve was 26% larger in fasting than in fed subjects. The half-life of cephradine in serum was 0.8 and 1.0 h in fasting and fed groups, respectively. Antimicrobial activity was detected in 49% of all salivary samples; in 75% of specimens, the concentrations were less than the 50% minimum inhibitory concentration for most pneumococci and group A streptococci. Urinary concentrations of cephradine ranged from 28 to 8,760 μg/ml and were independent of feeding status.
Comparison of eleven external fixators for treatment of unstable wrist fractures

Abstract We compared 11 external fixators for treatment of wrist fractures on the basis of rigidity, weight, cost, design characteristics, and provision for allowing wrist motion, and found important differences between them such as rigidity varying as much as 11 times. The Roger Anderson, Hanson Baylor Mini Hoffman, Rectangular Mini Hoffman, and Ace Colles external fixators are lightweight and have low rigidity. The C-series Hoffman unilateral frame and the A.O. have intermediate rigidity. The newly developed methylmethacrylate fixator, the regular Hoffman, the C-series Hoffman bilateral frame, and the Clyburn are more rigid. Althogh both the Clyburn and the Orthofix allow wrist flexion and extension, the Clyburn is lightweight and the Orthofix has the highest rigidity. These factors are analyzed and reported in a format that will guide the surgeon in the selection of an appropriate fixator for his patient with an unstable wrist fracture.
Long-Distance Radical Cation Migration through A/T Base Pairs in DNA: An Experimental Test of Theory

It is widely accepted that radical cations (holes) can migrate long distances in duplex DNA by a series of relatively short-range steps (hops). The mechanism for the short-range migration is not clearly understood. At one extreme, the radical cation is localized on guanines (G) and undergoes a unistep migration to a distant G by superexchange through a bridge of intervening A/T base pairs. Alternatively, the radical cation can reside on the bases of the A/T bridge, even though this appears to be prohibited by differences in oxidation potentials measured for the isolated DNA bases. We report experiments on DNA oligonucleotides in which GG steps are separated by (A/T)n bridges (n = 2−5) and a radical cation is introduced by irradiation of a covalently linked anthraquinone derivative. Quantitative assessment of the distance dependence of radical cation migration efficiency shows that it is incompatible with a mechanism that requires hole hopping exclusively by superexchange.
Letter detection in very familiar texts

In the present study, we investigated whether patterns of letter detection for function and content words in texts are affected by the familiarity of the material being read. In Experiment 1, subjects searched for target letters in sentences that had been rehearsed prior to performing the letter detection on them as well as on unfamiliar sentences. In Experiment 2, subjects searched for target letters in highly familiar verses (e.g., nursery rhymes) and in unfamiliar sentences that were matched to the familiar verses. A disadvantage in letter detection for function as compared with content words consistently found with unfamiliar passages was reduced significantly with the familiar material in both experiments. Specifically, letter detection for content words grew worse in familiar text, but letter detection for function words showed a contrasting modest, though nonsignificant, improvement. The results are consistent with the proposition that in very familiar texts, parafoveal analysis permits the identification of generally less familiar content words. Simultaneously, the normal pattern of weighing the structure and content elements of text changes so that more fixations on function words occur than when one is reading unfamiliar texts.
Data compatibility in the addiction sciences: An examination of measure commonality

The need for comprehensive analysis to compare and combine data across multiple studies in order to validate and extend results is widely recognized. This paper aims to assess the extent of data compatibility in the substance abuse and addiction (SAA) sciences through an examination of measure commonality, defined as the use of similar measures, across grants funded by the National Institute on Drug Abuse (NIDA) and the National Institute on Alcohol Abuse and Alcoholism (NIAAA). Data were extracted from applications of funded, active grants involving human-subjects research in four scientific areas (epidemiology, prevention, services, and treatment) and six frequently assessed scientific domains. A total of 548 distinct measures were cited across 141 randomly sampled applications. Commonality, as assessed by density (range of 0–1) of shared measurement, was examined. Results showed that commonality was low and varied by domain/area. Commonality was most prominent for (1) diagnostic interviews (structured and semi-structured) for substance use disorders and psychopathology (density of 0.88), followed by (2) scales to assess dimensions of substance use problems and disorders (0.70), (3) scales to assess dimensions of affect and psychopathology (0.69), (4) measures of substance use quantity and frequency (0.62), (5) measures of personality traits (0.40), and (6) assessments of cognitive/neurologic ability (0.22). The areas of prevention (density of 0.41) and treatment (0.42) had greater commonality than epidemiology (0.36) and services (0.32). To address the lack of measure commonality, NIDA and its scientific partners recommend and provide common measures for SAA researchers within the PhenX Toolkit.
Class conflict and class collaboration in regional rebellions, 1500 to 1700

I argue that distinctive regional modes of production entailed divergent configurations of interests and differing degrees of mutual dependence between peasants and landlords. Class-collaborative rebellions correlate highly with a mode of production that makes for cooperative interests and interclass dependence, while class-conflict rebellions correlate highly with a mode of production that makes for antagonistic interests and interclass independence. But class-collaboration was unlikely without a target, which the state provided. Yet the state became the target in subsistence regions where the lack of markets made the raising of tax revenues particularly difficult and where subsistence classes were not dependent on the state for markets and, therefore, had little incentive to cooperate with the state. On the other hand, in regions with a commercial mode of production, raising tax revenues was less burdensome and classes tended to be dependent on the state for markets and, therefore, less likely to engage in antistate collective action.
The electrochemical fluorination of N-containing carboxylic acids (Part 4). Fluorination of methyl 3-dialkylamino-isobutyrates and methyl 3-dialkylamino-n-butyrates

Abstract Several methyl esters of 3-dialkylamino-substituted n- and isobutyric acids have been subjected to electrochemical fluorination to give the corresponding perfluoroacid fluorides. Dimethyl, diethyl, pyrrolidino, morpholino, piperidino and N -methylpiperazino groups were investigated as dialkylamino substituents. The structure/yield relationship was evaluated both in terms of the structure of the acid and the kind of amino group, respectively. Better yields of perfluoroacid fluorides were obtained from methyl esters having isobutyric acid skeletons than those having n-butyric acid groups, and from the acids containing cyclic amino groups than those containing acyclic ones.
Carbodiimide metathesis catalyzed by vanadium oxo and imido complexes via imido transfer

Abstract Vanadium oxo and imido complexes: V(NC 6 H 4 Me)(O t Bu) 3 ( 1 ), V(NC 6 H 4 Me)Cl 3 ( 2 ), V(O)(O t Bu) 3 ( 3 ), V(O)(O i Pr) 3 ( 4 ), V(O)(acac) 2 ( 5 ), are catalysts for the metathesis of symmetrical carbodiimides (RNCNR, where R=cyclohexyl, isopropyl, and p -tolyl). At 138°C in p -xylene using 5 mol% of complexes 1 – 5 , the above carbodiimides are metathesized to the asymmetrical carbodiimides: N -cyclohexyl, N ′- p -tolylcarbodiimide ( 6 ), N -isopropyl, N ′- p -tolylcarbodiimide ( 7 ), N -cyclohexyl, N ′-isopropylcarbodiimide ( 8 ). An equilibrium mixture of carbodiimides is reached within minutes to hours depending on the catalyst employed. Yields obtained from gas chromatography range from 32 to 70%. Complex 2 is the most efficient catalyst with a turnover frequency greater than 100 h −1 . The oxo complexes ( 3 – 5 ) appear to be precatalysts. A mechanism is proposed for initiation with oxo complexes and a subsequent catalytic cycle involving imido complexes.
The Association of Acculturation and Health Literacy, Numeracy and Health-Related Skills in Spanish-speaking Caregivers of Young Children

Little is known about the relationship among acculturation, literacy, and health skills in Latino caregivers of young children. Latino caregivers of children < 30 months seeking primary care at four medical centers were administered measures of acculturation (SASH), functional health literacy (STOFHLA), numeracy (WRAT-3) and health-related skills (PHLAT Spanish). Child anthropomorphics and immunization status were ascertained by chart review. Caregivers (N = 184) with a median age of 27 years (IQR: 23-32) participated; 89.1% were mothers, and 97.1% had low acculturation. Lower SASH scores were significantly correlated (P < 0.01) with lower STOFHLA (ρ = 0.21), WRAT-3 (ρ = 0.25), and PHLAT Spanish scores (ρ = 0.34). SASH scores predicted PHLAT Spanish scores in a multivariable linear regression model that adjusted for the age of child, the age and gender of the caregiver, number of children in the family, the type of health insurance of the caregiver, and study site (adjusted β: 0.84, 95% CI 0.26-1.42, P = 0.005). This association was attenuated by the addition of literacy (adjusted β: 0.66, 95% CI 0.11-1.21, P = 0.02) or numeracy (adjusted β: 0.50, 95% CI -0.04-1.04, P = 0.07) into the model. There was no significant association between acculturation and up-to-date child immunizations or a weight status of overweight/obese. Lower acculturation was associated with worse health literacy and diminished ability to perform child health-related skills. Literacy and numeracy skills attenuated the association between acculturation and child health skills. These associations may help to explain some child health disparities in Latino communities.
NCAM 180 Acting via a Conserved C-Terminal Domain and MLCK Is Essential for Effective Transmission with Repetitive Stimulation

NCAM 180 isoform null neuromuscular junctions are unable to effectively mobilize and exocytose synaptic vesicles and thus exhibit periods of total transmission failure during high-frequency repetitive stimulation. We have identified a highly conserved C-terminal (KENESKA) domain on NCAM that is required to maintain effective transmission and demonstrate that it acts via a pathway involving MLCK and probably myosin light chain (MLC) and myosin II. By perfecting a method of introducing peptides into adult NMJs, we tested the hypothesized role of proteins in this pathway by competitive disruption of protein-protein interactions. The effects of KENESKA and other peptides on MLCK and MLC activation and on failures in both wild-type and NCAM 180 null junctions supported this pathway, and serine phosphorylation of KENESKA was critical. We propose that this pathway is required to replenish synaptic vesicles utilized during high levels of exocytosis by facilitating myosin-driven delivery of synaptic vesicles to active zones or their subsequent exocytosis.
Two‐Year Changes in L ipids and Lipoproteins Associated with the Maintenance of a 5 % to 10% Reduction in Initial Weight: Some Findings and Some Questions

WADDEN, THOMAS A., DREW A. ANDERSON, AND GARY D. FOSTER. Two-year changes in lipids and lipoproteins associated with the maintenance of a 5% to 10% reduction in initial weight: some findings and some questions. Obes Res. Objective This study assessed whether a 5% to 10% reduction in initial weight would be associated with as favorable long-term (i.e., 100 weeks) changes in lipids and lipoproteins, as have been observed on a short-term basis (i.e., 8 weeks). Research Methods and Procedures This was a prospective evaluation of 25 obese women, each of whom had lost ≥5% of initial weight during 48 weeks of treatment and had maintained a weight loss of this magnitude at 1-year follow-up (week 100). Lipids and lipoproteins were obtained at baseline and at weeks 8, 24, 48, and 100. All participants had a baseline total cholesterol ≥5.17 mmol/L (200 mg/dL). Results At the end of the first 8 weeks, weight fell an average of 11.7±2.8%, total cholesterol 20.6±7.5%, low-density-lipoprotein (LDL) cholesterol 23.0±18.1%, and triglycerides 26.0±20.1%. At week 48, weight had fallen to 20.1±7.0% below baseline, but total cholesterol and LDL cholesterol were reduced only 11.5±10.4% and 12.0±14.0% below baseline, respectively. These latter reductions were significantly (p 10% of initial weight had significantly greater reductions in total and LDL cholesterol values than did patients who maintained losses of only 5% to 10% of initial weight. Discussion Results of this study underscore the importance of assessing long-term changes in weight-related health complications when patients have lost weight but are no longer dieting (and exercising) as aggressively as they did during the initial months of treatment.
Preferential inclusion of extrachromosomal genetic elements in yeast meiotic spores

During meiosis and sporulation in the yeast Saccharomyces cerevisiae, extrachromosomal traits are efficiently transmitted to haploid spores. Although the pattern of inheritance of chromosomal traits reflects the mechanism of regular chromosomal segregation in meiosis, it is not known what processes are reflected by the efficient inheritance of extrachromosomal traits. Because extrachromosomal genetic elements in yeast are present in multiple copies, perpetuation of an extrachromosomal trait could occur by the passive envelopment of a subset of copies or by an active sequestering of all or a subset of copies within the four spores. We show that only subsets of the four extrachromosomal nucleic acids commonly found in yeast are transmitted through meiosis--55% of mitochondrial DNA copies, 82% of the 2-micron DNA plasmids, and about 70% of the L and M double-stranded RNAs. However, electron micrographs of serial sections through yeast asci indicate that the four spore enclose only 30% of the total ascus material. Thus these extrachromosomal elements are preferentially included within the spores, indicating that their inheritance is not a random process. Transmission of mitochondrial DNA can be accounted for by the observed enclosure of 52% of the mitochondrial volume within the spores. The high transmission frequencies of the double-stranded RNAs (which exist as virus-like particles in the cytoplasm) and 2-micron DNA must indicate that either these nucleic acids are actively recruited from the cytoplasm by some mechanism or they are associated in some way with the nucleus during meiosis.
Characterization of new transgenic Big Blue® mouse and rat primary fibroblast cell strains for use in molecular toxicology studies†

We have established and characterized primary mouse and rat cell strains for studies designed to complement in vivo gene mutation assays using the Big Blue(R) mouse or rat. Primary fibroblast cell strains, designated BBM1 and BBR1, were derived from a transgenic male Big Blue(R) B6C3F1 mouse and from a male Big Blue(R) Fischer-344 rat, respectively. Both BBM1 and BBR1 are genetically stable and mostly diploid. Both cell strains have low spontaneous frequencies of mutation at the lacI and cII loci as well as low frequencies of sister chromatid exchange and micronuclei formation. In addition, N-ethyl-N-nitrosourea (ENU) induces mutations at the cII locus in both BBM1 and BBR1 cells. These new primary Big Blue(R) mouse (BBM1) and rat (BBR1) fibroblast cell strains represent useful new models for molecular toxicology studies. Environ. Mol. Mutagen. 34:90-96, 1999 Published 1999 Wiley-Liss, Inc.
Phase-formation diagram for precursors to epitaxial growth of NiSi2 on Si(111).

Using reflection high-energy electron diffraction and Auger microanalysis in a custom-built ultrahigh vacuum scanning electron microscope we have identified six ordered structures that precede epitaxial ${\mathrm{NiSi}}_{2}$ during the annealing of nickel overlayers on Si(111). A novel technique of depositing through holes in a mask positioned near the sample allows us to obtain the complete coverage dependence of these structures in a single annealing cycle. The role of these structures in relation to the ${\mathrm{NiSi}}_{2}$ (B) (twinned) and ${\mathrm{NiSi}}_{2}$ (A) (nontwinned) structures is described.
Exploring space-time models for West Nile virus mosquito abundance data

Abstract This paper explores variant space-time models for log-transformed West Nile virus (WNv) mosquito data, which explicitly account for both local environmental conditions and complex dependent structures. Four space-time models take various forms to accommodate correlated structure in space and time, nested data, and nonstationarity. The average WNv mosquito abundance is captured by a global trend across all four models, but different model assumptions are imposed on the stochastic component of the proposed models: a simple multivariate linear regression model with independent and identical errors, a site-specific linear mixed model with temporally correlated errors, a week-specific linear mixed model with spatially correlated errors, and a local space-time kriging model. In a case study, the predictive performance of the four models was assessed using data collected in 2007 and 2008 for the Greater Toronto Area by the mosquito surveillance program of Ontario Ministry of Health and Long-term Care: the local space-time kriging model outperforms others, but closely followed by a site-specific linear mixed model with temporal correlation. Our findings suggest that the predictive accuracy of space-time WNv mosquito abundance models can be enhanced by explicitly taking into account spatiotemporal correlation, nonstationarity, and the data collection procedure, such as surveillance design, based on sound understanding of mosquito behavior and population dynamics.
Microfluidic enzyme-linked immunosorbent assay in a region of finite length

Abstract The current article presents a mathematical description of the distribution of the enzyme reaction product around an enzyme-linked immunosorbent assay (ELISA) region of finite length created within a microfluidic channel. An analytical expression has been derived for this diffusion-reaction system relating the measured signal to the various operating parameters in the limit of slow diffusion across the assay segments. The predictions of this model have been shown to agree well with the recent experimental reports by Yanagisawa et al. [18] on such a device. The current analysis also shows that quantitating ELISAs based on measurements made in the interfacial region between two assay segments is prone to error. However, such errors can be practically eliminated if the assay signal is collected from a region where this quantity deviates from its asymptotic limit far away from the interface by less than 5%. Moreover, the mathematical analysis suggests that the axial extent of an assay region (L) in these devices may be reduced to about 3 mm before signal cross-talk with its neighboring segments begins to affect the quantitation process. The reported value for L corresponds to a sample volume requirement of 3 nL per assayed analyte in a 10 μm deep and 100 μm wide microfluidic channel, which is nearly 3 orders of magnitude smaller than that required on microarray based platforms.
A new approximation for slotted buffered Aloha

Few models in wireless communications have been addressed as thoroughly as slotted Aloha, and most important questions regarding its performance have been answered (e.g., stability). Although slotted time finite user Aloha with infinite backlog (no queueing analysis) and fixed (common) contention probability is trivial, incorporating queueing significantly increases the complexity of the problem, with a corresponding major impact on the resulting performance. The stability region of this model is known, as are many other performance aspects, but a review of the literature yields no explicit performance expressions in terms of the fundamental model parameters. This paper approximates the performance of the K coupled queues with K uncoupled geom/geom/1 queues, where the queue parameters are selected to reflect the actual coupling as closely as possible. The throughput match is excellent, and the service delay match is good. The approach can be extended to queue-specific contention probabilities in a straightforward manner.