cssi/SciSciGPT-SciSciNet huggingface dataset:
The effect of grain orientation on nanoindentation behavior of model austenitic alloy Fe-20Cr-25Ni

Abstract Instrumented nanoindentation was used to investigate the hardness, elastic modulus, and creep behavior of an austenitic Fe-20Cr-25Ni model alloy at room temperature, with the indented grain orientation being the variant. The samples indented close to the {111} surfaces exhibited the highest hardness and modulus. However, nanoindentation creep tests showed the greatest tendency for creep in the {111} indented samples, compared with the samples indented close to the {001} and {101} surfaces. Scanning electron microscopy and cross-sectional transmission electron microscopy revealed slip bands and dislocations in all samples. The slip band patterns on the indented surfaces were influenced by the grain orientations. Deformation twinning was observed only under the {001} indented surfaces. Microstructural analysis and molecular dynamics modeling correlated the anisotropic nanoindentation-creep behavior with the different dislocation substructures formed during indentation, which resulted from the dislocation reactions of certain active slip systems that are determined by the indented grain orientations.
Using regional scale flow–ecology modeling to identify catchments where fish assemblages are most vulnerable to changes in water availability

Streamflow is essential for maintaining healthy aquatic ecosystems and for supporting human water supply needs. Changes in climate, land use and water use practices may alter water availability. Understanding the potential effect of these changes on aquatic ecosystems is critical for long-term water management to maintain a balance between water for human consumption and ecosystem needs. Fish species data and streamflow estimates from a rainfall-runoff and flow routing model were used to develop boosted regression tree models to predict the relationship between streamflow and fish species richness (FSR) under plausible scenarios of (1) water withdrawal, (2) climate change and (3) increases in impervious surfaces in the Piedmont ecoregion of North Carolina, U.S.A. Maximum monthly flow, the fraction of total flow originating from impervious surface runoff, coefficient of monthly streamflow variability, and the specific river basin accounted for 50% of the variability in FSR. This model was used to predict FSR values for all twelve-digit Hydrological Unit Code catchments (HUC-12s) in the North Carolina Piedmont under current flow conditions and under water withdrawal, climate change and impervious surface scenarios. Flow–ecology modeling results indicate that predicted FSR declined significantly with increased water withdrawals. However, the magnitude of decline varied geographically. A “hot-spot” analysis was conducted based on predicted changes in FSR under each scenario to understand which HUC-12s were most likely to be affected by changes in water withdrawals, climate and impervious surfaces. Under the 20% withdrawal increase scenario, 413 of 886 (47%) HUC-12s in the study area were predicted to lose one or more species. HUC-12s in the Broad, Catawba, Yadkin and Cape Fear river basins were most susceptible to species loss. These findings may help decision making efforts by identifying catchments most vulnerable to changing water availability. Additionally, FSR-discharge modeling results can assist resource agencies, water managers and stakeholders in assessing the effect of water withdrawals in catchments to better support the protection and long-term conservation of species.
Global cities and urban theory, by Donald McNeill: London, Sage, 2017

One could wonder about the value-added of an additional book on global cities, because there has been an exponential growth of publications on the topic. Nonetheless, Donald McNeill’s Global Cities...
Insomnia Caused by Medical Disorders

Virtually any medical condition can cause sleep disruption. The incidence of insomnia increases with age as medical problems increasingly occur, and patients with chronic insomnia are more likely to develop adverse health outcomes due to medical disease. There are multiple ways in which insomnia may be caused or aggravated by medical illness or bodily injury. Unpleasant stimuli can directly impede initiation of sleep, or they may cause frequent arousals or awakenings. Changes in basic systemic physiology (such as disorders of ventilation) may produce similar disruption in sleep continuity. There may be humoral changes that have direct neurochemical or neurophysiological effects, augmenting vigilance and lowering the threshold to arousal from sleep. The effects of acute and subacute sleep disruption can lead to chronic psychophysiological insomnia by creating the anticipation of disturbed sleep and by altering circadian entrainment, further accentuating the disruptive effects of the underlying medical condition. Difficulties with insomnia may persist long after the causative medical condition has been effectively managed.
Focal traumatic rupture of a dermoid cyst in a pediatric patient: case report and literature review

Dermoid cysts are rare congenital teratomas that can occasionally rupture and cause chemical meningitis, neurological deficit, or hydrocephalus. Rarely, dermoid cysts in the pediatric population can rupture spontaneously and even more rarely rupture due to trauma. To date, there are only five documented cases of traumatic rupture of a dermoid cyst. A 2-year-old male presented with 5 days of left eye ptosis and ophthalmoplegia after suffering a fall and was found to have a ruptured left anterior clinoid dermoid cyst that was surgically resected. The patient had significant improvement postoperatively. To the authors’ knowledge, this is the first reported case in the literature of a ruptured dermoid cyst after trauma in a pediatric patient and the first case of a traumatically ruptured dermoid cyst presenting with neurological deficit.
Inland impacts of atmospheric river and tropical cyclone extremes on nitrate transport and stable isotope measurements

Atmospheric rivers and tropical cyclones originate in the tropics and can transport high rainfall amounts to inland temperate regions. The purpose of this study was to investigate the response of nitrate (NO3−) pathways, concentration peaks, and stable isotope (δ15NNO3, δ18ONO3, δ2HH2O, δ18OH2O, and δ13CDIC) measurements to these extreme events. A tropical cyclone and atmospheric river produced the number one and four ranked events in 2017, respectively, at a Kentucky USA watershed characterized by mature karst topography. Hydrologic responses from the two events were different due to rainfall characteristics with the tropical cyclone producing a steeper rising limb of the spring hydrograph and greater runoff generation to the surface stream compared to the atmospheric river. Local minima and maxima of specific conductance, δ2HH2O, δ18OH2O, and δ13CDIC coincided with hydrograph peaks for both events. Minima and maxima of NO3−, δ15NNO3, δ18ONO3, and temperature lagged behind the hydrograph peak for both events, and the values continued to be impacted by diffuse recharge during hydrograph recession. Quick-flow pathways accounted for less than 20% of the total NO3− yield, while intermediate (30%) and slow-flow (50%) pathways composed the remaining load. However, hydrograph separation into quick-, intermediate-, and slow-flow pathways was not able to predict the timing of NO3− concentration peaks. Rather, the intermediate-flow pathway is conceptualized to experience a shift in porosity, associated with a change from epikarst macropores and fissures to soil micropores, with the arrival of water from the latter component likely causing peak NO3− concentration at the spring. Our results suggest that a more discretized conceptual model of pathways may be needed to predict peak nutrient concentration in rivers draining karst topography.
Who, When, How, and Why Bystanders Intervene in Physical and Psychological Teen Dating Violence:

Teen dating violence victimization is associated with a host of adverse mental and physical health problems. A number of bystander-focused interventions have been developed to mitigate the occurrence of abuse but with varying effectiveness. There remains a need to understand more about bystander behaviors used by adolescents to ensure that existing intervention components match with bystanders' attitudes and behaviors about intervening. The current study is a scoping review of existing literature on adolescents' use of bystander behaviors to determine who, when, how, and why adolescents intervene. Seventeen articles met inclusion criteria, the majority of which used qualitative or observational survey designs. Adolescents who either feel a sense of responsibility and confidence to intervene or are directly involved with or know the individuals involved in the dating violence are more likely to intervene. Adolescents intervene when they are able to define an act as dating violence and tend to intervene when the victim is female and when they have a supportive relationship with at least one teacher in their school. The various ways how bystander intervention is engaged in ranges from verbally or physically confronting the abuser, distracting the abuser, seeking support from an adult, to passively accepting the abuse. Reasons why adolescents intervene include believing the abuse is wrong and that intervening will diffuse the situation and help the victim. A number of barriers to bystander intervention emerged from analysis including individual attitudes and school climate factors. Implications for strengthening bystander intervention programs are discussed.
Excitatory/Inhibitory Imbalance in Anterior Lateral Occipital Complex Can Impair Hippocampal Mnemonic Discrimination.

Koolschijn et al. (2019) explore the influence of the release of cortical inhibition on neural mnemonic representations in the hippocampus and subsequent memory performance by evaluating neural activity via functional MRI, both before and after the application of tDCS aimed at increasing GABA in the anterior lateral occipital cortex.
Timothy R. Pauketat, An Archaeology of the Cosmos: Rethinking Agency and Religion in Ancient America

Timothy R. Pauketat, An Archaeology of the Cosmos: Rethinking Agency and Religion in Ancient America. London and New York: Routledge, 2013. Paperback (edition reviewed), 230 pp. inc. 85 illus., 8 tables. ISBN 9780415521291. £27.99. Hardback, 256 pages. ISBN 9780415521284. £95.00. eBook. ISBN 978020308518-9. £25.19.
Water availability drives population divergence and sex-specific responses in a dioecious plant.

PREMISE Water availability is an important abiotic factor, resulting in differences between plant species growing in xeric and mesic habitats. Species with populations occurring in both habitat types allow examination of whether water availability has acted as a selective force at the intraspecific level. Investigating responses to water availability with a dioecious species allows determination of whether males and females, which often have different physiologies and life histories, respond differently. METHODS An experiment varying water availability was performed under an outdoor rain-out shelter using plants from two mesic and two xeric populations of the dioecious plant Silene latifolia. Early growth rate, flowering propensity, flower size, and specific leaf area were measured. At the end of the season, the plants were harvested, aboveground and root biomass were measured, and the total number of flowers and fruit produced were counted. RESULTS Compared to the two mesic populations, plants from the two xeric populations grew more slowly, were less likely to flower, took longer to flower, had thicker leaves, invested less in aboveground biomass and more in root biomass, produced fewer flowers and fruit, but were more likely to live. Many traits exhibited significant habitat type × treatment interactions. Compared to the xeric populations, males-but not females-from mesic populations had less root biomass and greatly reduced their flower production in response to low water availability. CONCLUSIONS Mesic and xeric populations responded in ways congruent with water availability being a selective force for among-population divergence, especially for males.
Association of Atrial Fibrillation Without Cardiovascular Comorbidities and Stroke Risk: From the REGARDS Study.

Background Atrial fibrillation (AF) is associated with a 5‐fold increased stroke risk. While most patients with AF warrant anticoagulation, optimal treatment remains uncertain for patients with AF ...
Technology Acceptance Model: Investigating Students' Intentions toward Adoption of Immersive 360° Videos for Public Speaking Rehearsals.

Given the opportunities new technologies afford students and instructors, this mixed methods, longitudinal study examined factors impacting college students’ behavioral intentions for adopting virt...
Metalated isocyanides: formation, structure, and reactivity

Metalated isocyanides are highly versatile organometallics. Central to the reactivity of metalated isocyanides is the presence of two orthogonally reactive carbons, a highly nucleophilic “carbanion” inductively stabilized by a carbene-like isocyanide carbon. The two reactivities are harnessed in the attack of metalated isocyanides on π-electrophiles where an initial nucleophilic attack leads to an electron pair that cyclizes onto the terminal isocyanide carbon in a rapid route to diverse, nitrogenous heterocycles. Harnessing the potent nucleophilicity of metalated isocyanides while preventing electrophilic attack on the terminal isocyanide carbon has largely been driven by empirical heuristics. This review provides a foundational understanding by surveying the formation, structure, and properties of metalated isocyanides. The focus on the interplay between the structure and reactivity of metalated isocyanides is anticipated to facilitate the development and deployment of these exceptional nucleophiles in complex bond constructions.
Laser-etched grooves for rapid fluid delivery for a paper-based chemiresistive biosensor

Abstract Paper-based microfluidic devices are an attractive option for developing low-cost, point-of-care diagnostic tools. To incorporate more complex assays into paper, these devices must become more sophisticated, through the sequential delivery of different liquids or reagents without user intervention. Many flow control strategies focus on slowing the fluid down. However, this can lead to increased assay times and sample loss due to evaporation. We report the use of a CO2 laser to create etched grooves on paper to accelerate wicking speeds in paper-based microfluidic devices. We explored different laser settings to determine the optimal configuration. Our findings showed that simply cutting a slit into the paper created the fastest wicking channels. The slit acted as a macro capillary, allowing fluid to bypass the paper and speed it up. Further studies determined an ideal groove pitch of 0.75 mm (spacing in between grooves) for a paper channel. Additional experiments documented how sealing grooved channels with different adhesives can influence wicking. Overall, sealing the channels with tape made them wick faster. However, sealing methods such as lamination had a negative effect on wicking. Laser-etched grooves were successfully used to design a fluid-handling architecture for a chemiresistive paper-based biosensor. The grooves facilitated rapid, sequential delivery of sample and wash buffer. Human serum albumin spiked in phosphate buffer, artificial urine, and artificial saliva was successfully detected at as low as 15 pM. Etching grooves in paper is a simple process that requires no additional materials or chemicals, allowing single-step fabrication of paper-based microfluidic channels.
Trials in progress: A phase 1, open-label, dose-escalation, pharmacokinetic, safety and tolerability study of the selective TAM kinase inhibitor PF-07265807 in patients with advanced or metastatic solid tumors.

TPS2671Background: MERTK is a receptor tyrosine kinase from the tumor-associated macrophage kinase (TAMK) family that regulates key aspects of immune homeostasis and responses to infection. MERTK i...
The concept of vulnerability and resilience in electric power systems

The electric power system is one of the most vital infrastructures, and its security is necessary for the proper functioning of society. The main goal for the electric power system has traditionall...
Germ Cell Tumors

Germ cell tumors (GCTs) are a rare group of pediatric brain tumors that occur in the midline and often present with endocrinopathies including central diabetes insipidus (DI) or anterior pituitary deficiencies. Symptoms of central DI may be present in patients for months to years prior to definitive diagnosis. Patients may require long-term serial imaging and monitoring of tumor markers to ensure appropriate diagnosis and treatment. Germ cell tumors are subdivided into germinomas and nongerminomatous germ cell tumors (NGGCT) based on histology and tumor markers. Germinomas are quite radiosensitive, and historically have been treated with radiation therapy alone. NGGCTs are less responsive to radiation and require a more aggressive treatment approach with the addition of chemotherapy and sometimes surgery. Due to the complexities of diagnosis and management, these patients require a multidisciplinary approach to management including endocrinology, neurosurgery, neuro-oncology, radiation oncology, and neuro-ophthalmology.
Steric control of mesocate and helicate formation: Bulky pyrrol-2-yl Schiff base complexes of Zn2+

Abstract Regioisomerism about a phenyl spacer alters the number of nuclei which participate in self-assembly with pyrrole/schiff base ditopic ligands. The bulky benzyl ester substituents favor formation of di- and tetranuclear (but not trinuclear) complexes. The resulting unusual tetranuclear zinc molecular square is characterized and helicate versus mesocate formation is discussed.
Human Rhinovirus Infection of the Respiratory Tract Affects Sphingolipid Synthesis.

The 17q21 asthma susceptibility locus includes asthma risk alleles associated with decreased sphingolipid synthesis, likely resulting from increased expression of ORMDL3. ORMDL3 inhibits serine-palmitoyl transferase (SPT), the rate limiting enzyme of de novo sphingolipid synthesis. There is evidence that decreased sphingolipid synthesis is critical to asthma pathogenesis. Children with asthma and 17q21 asthma risk alleles display decreased sphingolipid synthesis in blood cells. Reduced SPT activity results in airway hyperreactivity, a hallmark feature of asthma. 17q21 asthma risk alleles are also linked to childhood infections with human rhinovirus (RV). This study evaluates the interaction of RV with the de novo sphingolipid synthesis pathway, and the alterative effects of concurrent SPT inhibition in SPT-deficient mice and human airway epithelial cells. In mice, RV infection shifted lung sphingolipid synthesis gene expression to a pattern that resembles genetic SPT deficiency, including decreased expression of Sptssa, a small SPT subunit. This pattern was pronounced in lung EpCAM+ epithelial cells and reproduced in human bronchial epithelial cells. RV did not affect Sptssa expression in lung CD45+ immune cells. RV increased sphingolipids unique to the de novo synthesis pathway in mouse lung and human airway epithelial cells. Interestingly, these de novo sphingolipid species were reduced in the blood of RV infected, wild-type mice. RV exacerbated SPT-deficiency-associated airway hyperreactivity. Airway inflammation was similar in RV-infected wild-type and SPT deficient mice. This study reveals the effects of RV infection on the de novo sphingolipid synthesis pathway, elucidating a potential mechanistic link between 17q21 asthma risk alleles and rhinoviral infection.
Utilizing Rapid Diagnostics for Detection of Candida Species

Rapid diagnostic tests are now available to aid in the detection of invasive candidiasis (IC) and promise significant advantages to conventional detection and identification methods. The most progress has been made on rapid species identification when blood culture bottles turn positive and/or when isolated pure colonies are available, while the diagnosis of IC directly from a clinical specimen (e.g., the patient’s blood) remains problematic. For the latter, nucleic acid-based tests (PCR, PCR/electrospray ionization-mass spectrometry (PCR/ESI-MS), and T2 magnetic resonance) and immunologic tests [1,3-β-D-glucan (BG) and Candida antigen and antibody tests] are promising but each contains certain limitations which have restricted their impact on clinical practice. In-house PCR assays are not standardized, and commercially available PCR tests are limited by minimal clinical data and a long turnaround time. The PCR/ESI-MS and T2 magnetic resonance platforms both require substantial up-front resources, and further clinical experience is required to understand their role in the clinical laboratory. Also, the BG and Candida antigen and antibody tests may be useful in certain scenarios (e.g., a negative BG may help rule out IC) but require significant clinical correlation and interpretation of results. On the other hand, PNA FISH and FilmArray Blood Culture ID Panel can substantially reduce the time-to-identification from a positive blood culture, impact clinical practice, and are quite reasonable to implement in the clinical laboratory. While the clear advantages for MALDI-TOF MS are speed, versatility, and excellent accuracy for identification of organisms from culture plates (which is its primary use in the clinical laboratory), further optimization is required before it can reliably be used for organism identification directly from blood culture bottles and its cost is currently prohibitively expensive for a small clinical laboratory. MALDI-TOF MS is very appealing, however, for rapid identification of organisms in a large clinical laboratory. All of these rapid diagnostic methods complement but do not replace the culture, however, as having the organism itself is still critical for susceptibility testing and strain typing
Using Bright Light and Melatonin to Adjust to Night Work

Publisher Summary Using bright light and melatonin to adjust to night work is indicated for people who want to work on a later schedule. This use of bright light and melatonin is specifically indicated for people who are working at least 2 consecutive weeks of night shifts, and particularly for workers engaged in high-risk work, such as nuclear power plant operators and health care workers. The circadian systems of night workers do not usually adjust to working at night and sleeping during the day. Instead, the circadian clock continues to promote sleep at night and wakefulness during the day. Thus, night shift work is associated with poor performance and excessive sleepiness during the night shift and poor daytime sleep at home. While hypnotics may pharmacologically induce daytime sleep, and stimulants (caffeine, modafinil) may reduce excessive sleepiness during the night shift, studies show that circadian-induced sleepiness during night shifts remains high. The health effects of the long-term use of these medications are unknown. Shift workers also have an increased risk for accidents, and for reproductive, cardiovascular, and gastrointestinal disorders and cancer. Many of these negative results are likely due in part to the chronic circadian misalignment that is characteristic of night work.
Caco-2 cell permeability vs human gastrointestinal absorption: QSPR analysis.

The aim of this study is to elucidate quantitative structure-permeability relationship (QSPR) of various organic molecules through Caco-2 cells, and to ascertain the relationship between gastrointestinal (GI) absorption in humans and Caco-2 cell permeability. Caco-2 cell permeability and human GI absorption data were obtained from the literature. The maximum hydrogen bond-forming capacity corrected for intra-molecular H-bonding (H b c ) and Lien’s QSAR model were used in this study. The latest CQSAR software was utilized in calculating the logarithm of partition coefficient in octanol/water (Clog P) and in deriving all regression equations. For 51 compounds, a significant correlation was obtained between Caco-2 cell permeability (log Pcaco-2)and Hbc, octanol/PBS (phosphate buffered saline, pH 7.4) distribution coefficient (log Doct), log MW and an indicator variable (I) for the charge, with a correlation coefficient of 0.797. When these compounds were divided into three subgroups, namely neutral, cationic and anionic compounds, much better correlations (r = 0.968, 0.915 and 0.931, respectively) were obtained using different combinations of various physicochemical parameters. A plot of human GI absorption vs. Caco-2 cell permeability obtained from different laboratories reveals that Caco-2 cell permeability cannot be used to precisely predict human GI absorption for compounds with Pcaco-2 below 5 x 10-6cm/s, due to interlaboratory and experimental variabilities, and the lack of a simple correlation between human GI absorption and Caco-2 cell permeability. Caco-2 cell permeability may be estimated from the structures of drug molecules using the above-mentioned physicochemical parameters. In general, for compounds with Pcaco-2)above 5 x 10-6cm/s, human GI absorption ranges from 50 to 100%. This is generally acceptable for development into oral dosage form. For the compounds with Pcaco-2)below 5 x 10-6cm/s, careful interpretation of caco- 2 cell permeability and use of internal standard for comparison are recommended. Otherwise, good drug candidates may be excluded due to incorrectly predicted poor absorption.
tert-butyl hydroperoxide-dependent microsomal release of iron and lipid peroxidation. II. Evidence for the involvement of nonheme, nonferritin iron in lipid peroxidation.

Abstract In a previous study tert -butyl hydroperoxide ( t -BOOH) was found to promote reductive release of nonheme, nonferritin iron from rat liver microsomes. The reaction was catalyzed by cytochrome P450 and was strictly contingent on the availability of ADP. In this study, t -BOOH was also found to promote microsomal lipid peroxidation, as evidenced by formation of malondialdehyde. t -BOOH-dependent lipid peroxidation was stimulated by ADP, and four lines of evidence suggested that such stimulation was mediated by reductive release and subsequent redox cycling of nonheme, nonferritin iron. First, lipid peroxidation was stimulated by the same concentration of ADP that promoted iron release. Second, depletion of nonheme, nonferritin iron by pretreatment of rats with phenobarbital decreased the stimulation of lipid peroxidation by ADP. Third, the effect of ADP was maximal when the concentration of t -BOOH was adjusted to values that yielded maximum iron release. Fourth, the effect of ADP was abolished by bathophenan-throline, which is known to chelate ferrous iron in a redox inactive form. These results suggest that the reductive release of nonheme, nonferritin iron exacerbates the deleterious effects of t -BOOH on microsomal lipids.
WHAS Radio and the Development of Broadcasting in Kentucky, 1922-1942

In the early 1920s, America was introduced to a new medium which would ultimately reach into virtually every home and affect every individual. The broadcast of election results on the evening of November 2, 1920, by radio station KDKA, Pitts burgh, awakened the country to the almost unlimited possibil ities of radio.1 While only KDKA was licensed to broadcast by the federal government in that first year, it was joined by twenty eight additional stations in 1921. By July 1922, over five hundred stations were licensed to operate in the United States.2 Compar ing it with the Oklahoma Land Boom or the California Gold Rush, Eric Barnouw has aptly described the radio craze during this era as a "Tower of Babel."J The rush to radio was so overwhelming that by June 1, 1922, California boasted of fifty stations, while New York re ported eighteen. Only seven states of the Union remained with out at least one radio station. Kentucky held that dubious dis tinction along with Delaware, Idaho, Mississippi, New Hamp shire, South Carolina, and Wyoming.4 Yet only six weeks later Kentucky entered the era of modern communications. At 7:30 p.m. on the warm evening of July 18, 1922, Credo Fitch Harris announced to all who cared or were able to listen: "This is
Central non-Pur.Pyr sequences in oligo(dG.dC) tracts and metal ions influence the formation of intramolecular DNA triplex isomers

The effect of the central non-Pur.Pyr sequences in oligo(dG.dC) inserts on determining the type of intramolecular DNA triplex isomers formed in negatively supercoiled plasmids was investigated. Different triplex types (H-r3, H-r5, and H-y3), revealed by a combination of chemical probing and Maxam-Gilbert sequencing reactions, were adopted by the oligo(dG.dC) tracts depending on the length and composition of the central non-Pur.Pyr sequences (0, 3, or 5 base pairs) and the kind of metal ions. The H-r3 triplex conformer, one isomer of a Pur.Pur.Pyr structure, was formed in the (C)20 and (C)10GCG(C)10 inserts in plasmids in the presence of certain metal ions. Interestingly, H-r5, the other isomer of the Pur.Pur-Pyr triplex which had not been detected previously, was formed in a (C)9GAATT(C)9 insert in the presence of either Mg2+ or Ca2+. Alternatively, H-y3, one isomer of a Pyr.Pur.Pyr triplex, was formed in the (C)9GAATT(C)9 insert in the absence of metal ions. Thus, central non-Pur.Pyr sequences and metal ions play a role as determinants of the types of intramolecular triplexes formed; they also reduce the requirement of longer Pur.Pyr repeat sequences to form intramolecular triplexes. Furthermore, the effects of MgCl2 concentration and pH on the formation of triplex isomers were examined. The Pur.Pur.Pyr conformations (H-r3 and H-r5) may be the favored conformations in the cellular milieu, since they are stable at physiological pH and metal ion concentration.
A Diffusion Equation with a Nonmonotone Constitutive Function

We discuss the well-posedness of the model problem ut = o(ux)x on [0,1] x [0,T], T > 0, subject to given Neumann or Dirichlet boundary conditions at x = 0 and x = 1, and to the initial condition u(x,0) = f(x); the given functions f: [0,1] → R, o: R → R are assumed to be smooth, o(0) = 0, o satisfies the coercivity assumption Ęo(Ę) > cĘ2, for some constant c > 0 and for Ę Є R, and o is assumed to be decreasing on an interval (a,b) with a > 0. We present a recent nonuniqueness result in the special case when o is piecewise linear and study a related convexified problem.
Gabor Function Based Medical Image Compression

Compression methods based on Gabor functions are implemented for simulated nuclear medicine liver images with and without lesions. The performance of the compression schemes is assessed objectively by comparing the original images to the compressed/reconstructed images through calculation of the Hotelling trace, an index that has been shown to correlate well with performance for images from this imaging modality. Gabor-based compression has not previously been implemented on medical images, nor has any rigorous task-based measure of quality been used to assess the compression. For compression based on thresholding the complex Gabor coefficients, a better than 2∶1 compression is obtained without appreciable reduction in image quality, which when combined with gains expected from bit reduction schemes, corresponds to an overall approximate 8∶1 compression. A large number of nuclear medicine liver images with and without space-occupying lesions were simulated. Then a compression scheme based on transformation of the images into the “information space” proposed by Gabor [1] was implemented. Two tasks were examined: 1) determination of the presence or absence of the lesion in a given location, and 2) determination of the presence or absence of the lesion in one of several locations. The task-based performance using the compressed/reconstructed images is compared to that using the original images according to the Hotelling trace criterion.
Static compaction for two-pattern test sets

We propose a static compaction procedure to reduce the size of a test set comprised of two-pattern tests. The procedure reorders the tests in the test set to maximize the number of faults detected by adjacent patterns, thus allowing some of the tests to be dropped. In addition, the procedure removes redundant tests and redundant patterns, that can be omitted without reducing the fault coverage. Experimental results are presented to evaluate the effectiveness of the compaction procedure.
Measuring the in situ Kd of a genetically encoded Ca2+ sensor.

The use of genetically-encoded Ca2+ sensors (GECIs) for long-term monitoring of intracellular Ca2+ has become increasingly common in the last decade. Emission-ratiometric GECIs, such as those in the yellow cameleon family, are capable of making quantitative measurements, meaning that their fluorescence signals can be converted to free Ca2+ concentrations ([Ca2+]free). This conversion is only as accurate as the sensor’s apparent dissociation constant for Ca2+ (Kd’), which depends on temperature, pH, and salt concentration. This protocol describes a method for performing a titration, in living cells (in situ), of cytosolic, nuclear, or mitochondrial sensors. An excellent example of calibration of an ER-targeted sensor is presented elsewhere (Rudolf et al. 2006).
Near-zero linking difference upon transcription factor IID binding to promoter DNA.

Abstract Binding of yeast transcription factor IID (TFIID) to the adenoviral major late promoter in circular DNA molecules caused a linking number change of less than 0.1. TFIID on its own therefore fails to unwind DNA appreciably, or else it causes both unwinding and compensatory writhing. Highly purified, recombinant yeast TFIID relaxed supercoiled DNA, because of a contaminant of bacterial topoisomerase I. Relaxing activity of topoisomerase I was enhanced by the adenoviral major late promoter, suggesting an instability of the TATA sequence or a destabilizing effect on flanking DNA.
Mammographic Image Quality

Production of good quality radiographic images of the breast that are of diagnostic value place severe restrictions on the entire imaging system and, in particular, the recording media. A parallel clinical and physical investigation is in progress to evaluate the diagnostic capabilities of the three types of recording media presently in mammography. These will be described and initial results of the evaluation program given.
Increasing eye contact by head-holding

Abstract This study assessed the effectiveness of a head-holding procedure for establishing eye contact with a developmentally delayed child who had not acquired the response via positive reinforcement techniques. A multiple baseline across four behaviors demonstrated that the head-holding procedure substantially increased eye contact for each treated behavior. The head-holding procedure offers one alternative to the clinician who has demonstrated the ineffectiveness of positive procedures in establishing eye contact with a particular child.
Mechanical twinning in small quartz crystals

Quartz is known to be ferrobielastic; that is, quartz crystals have domain states (Dauphine twins) which differ in their elastic compliance values and which can be switched by an appropriately oriented stress. Polycrystalline quartz has also been reported (Tullis 1970) to show preferential orientation of these domains following application of large uniaxial stresses.
A multi-agent design for sense and respond logistics simulation

Sense and Respond Logistics (SARL) is a highly flexible, agile, and adaptive methodology for managing logistics resources in a network-centric and information rich environment. Designing and developing the software for simulating a system with such complexity presents challenges that stem from the role of heterogeneous communication channels and decision choices that produce non-deterministic outcomes. We describe the use of multi-agent approaches for simulating SARL applications. We also argue for the use of formal methods and aspect-oriented techniques in the design of these simulations, to assist in supporting model validation and verification. Features of an aspect-oriented, multi-agent, architectural description languages are also presented as a mechanism for reasoning about cross-cutting concerns.
Cellulose derivatives with low DS. II. Analysis of alkanoates

The determination of the degree of substitution (DS) of cellulose alkanoates representing a wide range of ester types (acetate (C-2), to stearate (C-18), with a DS of 0 to 3) was performed by 1H-NMR spectroscopy and aminolysis/gas chromatography. Poor solubility combined with complex substituent signals preclude proton NMR spectroscopy as a method of analysis when the DS of alkanoates falls below one. This is true for all ester-derivative types, especially for the derivatives with bulky substituent groups. By contrast, the aminolysis/gas chromatography method is independent of both solubility and DS, and thus represents the method of choice for cellulose esters which have low degrees of substitution and bulky substituent groups.
VELOCITY ANALYSIS FOR WIDE APERTURE SEISMIC DATA

Common midpoint data are now being collected with ever increasing source-receiver offsets. For wide aperture seismic data classical methods of interpretation fail, since velocity analyses and signal-to-noise enhancement methods based on hyperbolic traveltime curves are no longer appropriate. Therefore, the goals of increased velocity resolution and signal enhancement, which motivate the increase in offset, are not achieved. Approximate methods, involving higher order traveltime curves or extrapolations, have been developed for velocity analysis but these are ineffective in the presence of refracted arrivals, and lack a physical basis. These problems can be minimized by transforming the observational data to the domain of intercept or vertical delay time τ and horizontal ray parameter p . In this domain headwave refractions are collapsed into points and both near vertical and wide angle reflections can be analyzed simultaneously to derive velocity-depth information, even in the presence of velocity gradients or low velocity zones.
Tumor metabolism: cancer cells give and take lactate

Tumors contain well-oxygenated (aerobic) and poorly oxygenated (hypoxic) regions, which were thought to utilize glucose for oxidative and glycolytic metabolism, respectively. In this issue of the JCI, Sonveaux et al. show that human cancer cells cultured under hypoxic conditions convert glucose to lactate and extrude it, whereas aerobic cancer cells take up lactate via monocarboxylate transporter 1 (MCT1) and utilize it for oxidative phosphorylation (see the related article beginning on page 3930). When MCT1 is inhibited, aerobic cancer cells take up glucose rather than lactate, and hypoxic cancer cells die due to glucose deprivation. Treatment of tumor-bearing mice with an inhibitor of MCT1 retarded tumor growth. MCT1 expression was detected exclusively in nonhypoxic regions of human cancer biopsy samples, and in combination, these data suggest that MCT1 inhibition holds potential as a novel cancer therapy.
The Effect of Texture Shape on the Load-Carrying Capacity of Gas-Lubricated Parallel Slider Bearings

Surface texturing is used to increase hydrodynamic pressure and reduce friction and wear between gas-lubricated parallel sliding surfaces. The shape, geometry, and density of the patterned microtexture features (“dimples”) play a key role in the tribological performance of the textured slider bearings. The objective of this paper is to compare the load-carrying capacity of commonly used dimple shapes for gas-lubricated textured parallel slider bearings. Six different texture shapes are considered, including spherical, ellipsoidal, circular, elliptical, triangular, and chevron-shaped dimples. The pressure distribution and load-carrying capacity generated by different texture shapes are simulated using the compressible Reynolds equation over a domain containing a column of ten dimples. The texture geometry and density are optimized in terms of maximum load-carrying capacity for each individual dimple shape, as a function of operating parameters such as relative velocity and spacing between the two sliding surfaces. The maximum load-carrying capacity of each individual texture shape—with optimized geometry and density—is then compared relative to each other. It is concluded that the ellipsoidal shape results in the highest load-carrying capacity, and the optimal geometry and density are found to be almost independent of the operating conditions.
Neurochemical and physiological correlates of a critical period of respiratory development in the rat.

Despite its vital importance to life, respiration is not mature at birth in mammals, but rather, it undergoes a great deal of growth, refinement, and adjustments postnatally. Many adjustments do not follow smooth paths, but assume abrupt changes during certain postnatal periods that may render the animal less capable of responding to respiratory stressors. The present review focuses on neurochemical and physiological correlates of a critical period of respiratory development in the rat. In addition to an imbalanced expression of reduced excitatory and enhanced inhibitory neurotransmitters, a switch in the expressions of gamma-aminobutyric acid (GABA)A receptor subunits from alpha3 to alpha1 occurs around postnatal day (P)12 in the pre-Botzinger nucleus and the ventrolateral subnucleus of the solitary tract nucleus. Possible subunit switches in a number of other neurotransmitter receptors are discussed. These neurochemical changes are paralleled by ventilatory adjustments at the end of the second postnatal week. At P13 and under normoxia, respiratory frequency reaches its peak before assuming a gradual fall, and both tidal volume and minute ventilation exhibit a significant rise prior to a plateau or a gradual decline until P21. The response to acute hypoxia is markedly reduced between P12 and P16, being lowest at P13. Thus, the end of the second postnatal week can be considered as a critical period of respiratory development, during which multiple neurochemical and physiological adjustments and switches are orchestrated at the same time, rendering the system extremely dynamic but, at the same time, vulnerable to externally imposed perturbations and insults. The critical period embodies a time of multi-system, multifaceted growth and adjustments. It is a plastic, transitional period that is also a part of the normal development of the respiratory system.
Threshold voltage models of the narrow-gate effect in micron and submicron MOSFETs

Abstract Modeling of the narrow gate effect on the threshold voltage shift (ΔVT) and the effective channel width (WCE) by Ji and Sah, based on the solution of the Poisson equation for the two-dimensional (2-D) potential distribution using the depletion approximation, has been improved by removing the depletion approximation. A simple two-parameter analytical formula for predicting the threshold voltage shift of a narrow gate MOSFET with gate width (WG) in the micron and submicron ranges, was proposed and tested against 2-D numerical results, showing good accuracy. Both parameters can be extracted easily from the theoretical 2-D computed or experimental drain conductance-gate voltage characteristics. Moreover, the new model shows that the threshold voltage shift of any given MOSFET with a known WCE can be determined based only on one test device. Therefore, in applications, computation time can be reduced considerably by using the proposed analytical formula to compute the threshold voltage of any given MOSFET. The new analysis and model show smaller threshold voltage shift than the Ji-Sah's depletion approximation model as the gate narrows due to the loss of gate induced charge to fringe fields at the gate edges. Comparison of the threshold voltage shift between the new model and Acker's model shows that the inverse relationship between ΔVT and WCE instead of WG accounts for the inaccuracy of the simple charge control model when the gate width is reduced to the submicron range.
Binding of pigment epithelium-derived factor (PEDF) to retinoblastoma cells and cerebellar granule neurons. Evidence for a PEDF receptor

Pigment epithelium-derived factor (PEDF) has neuronal differentiation and survival activity on retinoblastoma and cerebellar granule (CG) cells. Here, we investigated the presence of PEDF receptors on retinoblastoma Y-79 and CG cells. PEDF radiolabeled with (l25)I remained biologically active and was used for radioligand binding analysis. The binding was saturable and specific to a single class of receptors on both cells and with similar affinities (K(d) = 1.7-3.6 nM, B(max) = 0.5-2.7 x 10(5) sites/Y-79 cell; and K(d) = 3.2 nM, B(max) = 1.1 x 10(3) sites/CG cell). A polyclonal antiserum to PEDF, previously shown to block the PEDF neurotrophic activity, prevented the (125)I-PEDF binding. We designed two peptides from a region previously shown to confer the neurotrophic property to human PEDF, synthetic peptides 34-mer (positions 44-77) and 44-mer (positions 78-121). Only peptide 44-mer competed for the binding to Y-79 cell receptors (EC(50) = 5 nM) and exhibited neuronal differentiating activity. PEDF affinity column chromatography of membrane proteins from both cell types revealed a PEDF-binding protein of approximately 80 kDa. These results are the first demonstration of a PEDF-binding protein with characteristics of a PEDF receptor and suggest that the region comprising amino acid positions 78-121 of PEDF might be involved in ligand-receptor interactions.
An Essay In The Aid Of Writing History: Fictions Of Historiography

In what follows I explore the question of fictionality in history writing. First, I venture into the unfamiliar genre of ego-histoire and make my own professional training in the tenets of positivist or realist historiography an object of theoretical reflection and critical analysis. Then as a way of dealing with the literary dimension of written history, I make a canonical work in history of education an object of rhetorical analysis. Finally, as another way of coming to terms with the “fictions of historiography,” I revisit one of my own productions and make it an object of metacritical consideration. My central theme is that historiographical realism alone will not suffice , that historians are as dependant upon literary invention as upon documents, that history cannot be written without the aid of the “fictions of historiography,” and that the difference between the historian and the novelist is narrower than we may have been accustomed to think. I further argue that attention to the literary or rhetorical dimension of history is long overdue in history of education, where it flourishes unacknowledged. I conclude that historical writing is not just a literary pastime and the issue remains: how to come to grips with fictionalizing and the truth claims of historiography.
Rectal misoprostol versus intravenous oxytocin for the prevention of postpartum hemorrhage after vaginal delivery.

Abstract Objective: To compare rectally administered misoprostol to intravenously administered oxytocin for the management of third-stage labor. Study Design: Subjects were randomized to receive two, 200-μg misoprostol tablets rectally (study medication) plus 2 mL saline in Ringer's lactate intravenously or two lactose tablets rectally plus 20 units oxytocin in Ringer's lactate intravenously (control medication). Blood loss was determined by estimation, measurement, and change in hematocrit values from admission to postpartum day 1. Subjects were excluded if cesarean delivery was required. Results: A total of 325 women underwent analysis. By estimation, 21% of subjects and 15% of controls had postpartum hemorrhage ( P =.17). By using measured blood loss, we determined that 70 of 154 (46%) study subjects and 61 of 161 (38%) control subjects had postpartum hemorrhage ( P =.17). For 36 (23%) misoprostol subjects and 18 (11%) oxytocin subjects at least one additional agent was required to control bleeding ( P =.004). Conclusion: Rectal misoprostol (400 μg) was no more effective than intravenous oxytocin in preventing postpartum hemorrhage. (Am J Obstet Gynecol 2001;185: 878-82.)