cssi/SciSciGPT-SciSciNet huggingface dataset:
Retrieval conditions and false recognition: Testing the distinctiveness heuristic.

High levels of false recognition are observed after people study lists of semantic associates that all converge on a nonpresented lure word. In previous experiments, we have found that orienting participants to encode distinctive information about study list items by presenting them as pictures as opposed to words produces marked reductions in false recognition. We have suggested that these reductions reflect the operation of a distinctiveness heuristic: Participants demand access to detailed pictorial information in order to support a positive recognition decision. The present experiments provide additional evidence on this point and allow us to distinguish between the distinctiveness heuristic account and an alternative account based on the impoverished encoding of relational information that occurs when one is studying pictures. In Experiment 1, even when only half of the items in a study list were presented as pictures, a general suppression of false recognition was observed that could be attributable to impoverished encoding of relational information. Experiment 2 provided a critical test of the distinctiveness heuristic account: We manipulated test instructions and found that differences in false recognition rates between picture and word encoding were attenuated in a retrieval condition that did not encourage reliance on a distinctiveness heuristic.
Amino acid incorporation into rat spinal cord and brain after simultaneous and interval sciatic nerve lesions

The incorporation of [3H]lysine into the trichloracetic acid (TCA) precipitable protein and soluble fractions of brain and spinal cord of rats subjected to immediate transection distal and crush proximal or transection distal, two week interval, and crush proximal of the left sciatic nerve has been studied at 5, 11, and 18 days postoperative. In addition, the regeneration of the nerve fibers was measured. A greater rate of (P 18 day group > 5 day group. However, no significant differences in uptake into protein in spinal cord and brain were seen between the simultaneous lesion sciatic animals over postoperative days. In brain, differences between the [3H]lysine incorporation into protein of the left (L) and right (R) cortical hemispheres was noted. The incorporation into somatomotor cortex showed a L > R difference which was most pronounced after simultaneous sciatic nerve lesion. Interestingly, the largest R > L difference was in occipital cortex after interval lesions of sciatic nerve. In spinal cord, the protein radioactivity of the L5–6 and S1–4 segments which include most of the affected neurons was greater on the right (unlesioned) side than on the left (sciatic crush) side over all lesioned animals. This effect was most pronounced after interval sciatic lesion. The alteration of central nervous system incorporation of lysine after peripheral nerve (sciatic) lesion and regeneration are discussed.
E-prints and the Open Archives Initiative.

The Open Archives Initiative (OAI) was created as a practical way to promote interoperability between e‐print repositories. Although the scope of the OAI has been broadened, e‐print repositories still represent a significant fraction of OAI data providers. This article presents a brief survey of OAI e‐print repositories, and of services using metadata harvested from e‐print repositories using the OAI protocol for metadata harvesting (OAI‐PMH). It then discusses several situations where metadata harvesting may be used to further improve the utility of e‐print archives as a component of the scholarly communication infrastructure.
Identification of causative foods in children with eosinophilic esophagitis treated with an elimination diet

Background Eosinophilic esophagitis (EoE) is a chronic inflammatory disease with isolated eosinophils in the esophagus predominantly triggered by foods. The optimal testing to identify inciting foods remains unclear. Objectives We sought to determine the effectiveness of allergy testing-directed diets in patients with EoE. Methods A retrospective analysis of all children with EoE seen at the Children's Hospital of Philadelphia between 2000 and 2011 identified 941 patients with EoE. Skin prick tests (SPTs) and atopy patch tests (APTs) were conducted, and predictive values were calculated. IgE-mediated food reactions were also identified. A food was considered to cause EoE if its elimination led to resolution of esophageal eosinophilia or reintroduction led to reoccurrence of EoE. The effectiveness of the various elimination diets was compared with targeted food antigen elimination. Results Definitive foods causing EoE were identified, with milk, egg, wheat, and soy as the most common foods in 319 patients. IgE-mediated reactions (urticaria and anaphylaxis) were seen in 15%. The negative predictive value for the combination of SPTs and APTs averaged 92%, with the exception of milk at 44%, and the positive predictive value averaged 44%. An empiric 6-food elimination diet or removal of positive foods on allergy testing (SPTs/APTs) both had a histologic success rate of 53%. Removal of foods identified on SPTs/APTs plus empiric elimination of milk leads to resolution in 77% of patients. Conclusion An elimination diet based on SPT/APT results leads to resolution of esophageal eosinophilia in a similar proportion of patients as empiric removal of foods but required that fewer foods be removed. These observations suggest that both methods are acceptable options.
Synthesis of 4-methyldienoates using a vinylogous Horner-Wadsworth-Emmons reagent. Application to the synthesis of trichostatic acid.

The utility of the unsaturated phosphonate 1 as a vinylogous Horner−Wadsworth−Emmons reagent was explored in reactions with aldehydes affording 4-methyldienoate esters. Factors that affect E/Z selectivity were studied. A simplified synthesis of trichostatic acid 3 was accomplished to demonstrate utility of this reagent.
Genetics and taxonomy of ribbed mussels (Geukensia spp.)

Ribbed mussels (232 in all) representing the nominal species Geukensia demissa (Dillwyn, 1817) were collected at nine coastal North American locations (two Pacific, four Atlantic and three Gulf Coast locations) between January 1990 and September 1991, and examined for nine shell characters and for variation at 18 allozyme loci. Two genetically-differentiated groups were identified and called demissa-type and granosissima-type mussles, based on similarity of geographic range to previously recognized subspecies of G. demissa. There was very little genetic differentiation of populations over moderate to large (3000 km) distances along the Atlantic coast (for demissa-type mussels), along the Gulf Coast (for granosissima-type mussels), or between Pacific and Atlantic populations of demissa-type mussles. The two types of mussels were differentiated genetically (Nei's unbiased genetic distance =0.55±0.20) at a level characteristic of separate species in other molluscan taxa, and to a lesser extent were differentiated morphologically. We recommend that the two types of mussels be treated as separate species within the genus Geukensia: G. demissa (Dillwyn, 1817) and G. granosissima (Sowerby, 1914).
Web‐enabled product ID system as a tool in pharmaceutical marketing

Purpose – The purpose of this paper is to explore how a web‐enabled product ID system can be applied to pharmaceutical marketing and consumer relationship management.Design/methodology/approach – As a technical paper, it first introduces and describes the product ID system and then explores various marketing applications of this interactive communication tool in the pharmaceutical industry. Finally, it concludes with managerial implications and caveats.Findings – The web‐based product ID system is able to provide a means for product validation and database marketing, facilitate interactive marketing communication and viral marketing, and collect customer information and feedback for research activities.Research limitations/implications – The perceived lack of security of public networks and customer confidence about drug sourcing are always concerns when applied to online technology in pharmaceutical marketing. Caveats about building such a system of coded ID product are discussed.Practical implications –...
Effects of antimony additions on the fracture of nickel at 600°C

Abstract Antimony additions (~1 wt%) are found to drastically lower tensile ductility and induce extensive intergranular cracking in nickel at 600°C. This effect is most pronounced at lower strain rates. These results are contrasted to results for pure nickel where ductility is high and failure occurs via plastic instability. Scanning electron microscopy revealed faceting of crack and cavity surfaces in the antimony doped nickel. Auger electron spectroscopy revealed segregation of antimony and (residual) sulfur to both grain boundaries and to the internal free surfaces of cracks and cavities. Inert ion sputter profiling showed that most of the antimony and sulfur enrichment on these surfaces is confined within a few atom layers of the interface. The embrittling influence of antimony is discussed in terms of the observed antimony and sulfur segregation to internal interfaces. Possible connections between the segregation and the observed embrittlement involve segregation effects on grain boundary sliding, grain boundary and surface diffusivities and interfacial energetics.
Do HRM practices influence the desire for unionization? Evidence across workers, workplaces, and co-workers for Great Britain

We investigate the desire of nonunion workers in Great Britain to become represented by unions. Comparing our results to those from the United States, we find that workers in Great Britain are less likely to desire unionization and express lower dissatisfaction with their influence at work. The determinants of the desire for unionization are estimated controlling for a wide variety of individual and workplace variables. The roles of human resource management and employee involvement are isolated. We identify direct work-place and worker-level effects of these practices in reducing the desire for unionization and an indirect effect operating through the influence of employee relations, a major determinant of the desire for unionization. Also, we identify characteristics of co-workers that are associated with desire for unionization and examine the role information revelation may play in managerial strategies to forestall unions.
Over‐promising and under‐delivering? Ambitions and risks in US defence strategy

Recent changes to US defence strategy, plans and forces have placed the United States at greater risk of over-promising and under-delivering on its global security ambitions. In 2012, the Obama administration released a new defence strategic guidance document to adapt to a shifting security environment and defence budget cuts. The guidance upholds the two long-standing American goals of global pre-eminence and global reach, but seeks to apply this military power by using new planning and regional concepts. It revises the Department of Defense's force planning construct, an important tool used to size US military forces, and identifies the Asia–Pacific and the greater Middle East as the two regions where the US military should focus its attention and resources. There are three major risks facing this revised US strategy: emerging security threats, the role of US allies and partners, and domestic constraints in the United States. Included in these risks are the proliferation of advanced military technologies, the US response to the rise of China, the continued prevalence of state instability and failure, the capability and commitment of NATO and other US allies, additional US budget cuts, political polarization in the United States, and interservice competition within the US military. In light of these risks, the United States faces a future in which it will continue to struggle to direct its military power towards its most important geopolitical priorities, such as rebalancing towards the Asia–Pacific, as opposed simply to respond to the many security surprises that are certain to arise. If the past is any guide, American political leaders will respond to the aforementioned risks in the worst way possible: by maintaining the current US defence strategy while slashing the resources to support it.
Feeding supplemental fat and undegraded intake protein to early lactation dairy cows.

Abstract Forty-eight Holstein cows (16 primiparous) were fed alfalfa silage-based TMR containing 18% CP with 33 or 36% of the CP as undegraded intake protein and with 0 or 2.8% supplemental fat (DM basis). Expeller soybean meal replaced solvent soybean meal to vary undegraded intake protein, and sodium alginatetreated tallow was used as the fat source. A standard diet containing solvent soybean meal without fat was fed during the first 21 d postpartum for covariate adjustment of milk production. A continuous lactation design with 2 × 2 factorial arrangement of treatments was used with supplemental fat and undegraded intake protein as main effects. Feeding supplemental fat increased actual milk (32.9 vs. 31.7 kg/d) but decreased milk protein concentration. Cows fed supplemental fat also had higher BW, and weight gain was significant with time. Increasing undegraded intake protein did not affect milk yield, composition, or component yield. There were no significant interactions between supplemental fat and undegraded intake protein on milk yield or composition. Milk fatty acid composition was not altered by addition of undegraded intake protein, but C 6 to C 14 fatty acids were reduced by adding supplemental fat. Results do not support the strategy of increasing levels of undegraded intake protein when supplemental fat is fed. Variation in undegraded intake protein content of feedstuffs appears to be of more importance in ration formulation than interactions between supplemental fat and protein.
Training Foreign Teaching Assistants: Cultural Differences

(1987). Training Foreign Teaching Assistants: Cultural Differences. College Teaching: Vol. 35, No. 2, pp. 67-69.
Robust Multi-Objective Feedback Design by Quantifier Elimination

This paper shows how certain robust multi-objective feedback design problems can be reduced to quantifier elimination (QE) problems. In particular it is shown how robust stabilization and robust frequency domain performance specifications can be reduced to systems of polynomial inequalities with suitable logic quantifiers, ? and ?. Because of computational complexity the size of problems that can solved by QE methods is limited. However, the design problems considered here do not haveanalyticalsolutions, so that even the solution of modest-sized problems may be of practical interest.
Trimethoprim-sulfamethoxazole-associated acute febrile neutrophilic dermatosis: Case report and review of drug-induced Sweet's syndrome

Abstract Sweet's syndrome, or acute febrile neutrophilic dermatosis, is characterized by fever, neutrophilia, and painful erythematous cutaneous plaques that contain a dense neutrophilic dermal infiltrate. Although the disorder is usually idiopathic, patients with drug-induced Sweet's syndrome have been described. We describe a 50-year-old woman with trimethoprim-sulfamethoxazole (TMP-SMX)-induced Sweet's syndrome and review the features of the 13 previously reported patients with drug-induced Sweet's syndrome. All patients had fever, painful skin lesions (most commonly on the upper extremities), and a biopsy-confirmed neutrophilic dermatosis. All patients also exhibited a temporal relationship between drug administration and clinical presentation and between drug withdrawal and healing. In patients with drug-induced Sweet's syndrome, neutrophilia is often absent.
Demonstration of a nonmagnetic blazed-grating atomic beam splitter

We demonstrate a coherent atomic beam splitter for metastable helium atoms, based on the diffraction of atomic matter waves from a blazed phase grating. The beam splitter is created by driving the two transitions of a three-level V system with differentially detuned standing light waves that have a relative spatial phase shift of pi/2. The light f ields create a potential that is approximately triangular as a function of position in the laser field. Splittings of 38 times the photon momentum have been observed.
Structural characterization of apomyoglobin self-associated species in aqueous buffer and urea solution.

The biophysical characterization of nonfunctional protein aggregates at physiologically relevant temperatures is much needed to gain deeper insights into the kinetic and thermodynamic relationships between protein folding and misfolding. Dynamic and static laser light scattering have been employed for the detection and detailed characterization of apomyoglobin (apoMb) soluble aggregates populated at room temperature upon dissolving the purified protein in buffer at pH 6.0, both in the presence and absence of high concentrations of urea. Unlike the β-sheet self-associated aggregates previously reported for this protein at high temperatures, the soluble aggregates detected here have either α-helical or random coil secondary structure, depending on solvent and solution conditions. Hydrodynamic diameters range from 80 to 130 nm, with semiflexible chain-like morphology. The combined use of low pH and high urea concentration leads to structural unfolding and complete elimination of the large aggregates. Even upon starting from this virtually monomeric unfolded state, however, protein refolding leads to the formation of severely self-associated species with native-like secondary structure. Under these conditions, kinetic apoMb refolding proceeds via two parallel routes: one leading to native monomer, and the other leading to a misfolded and heavily self-associated state bearing native-like secondary structure.
Cloning, Characterization, and Expression of Animal Toxin Genes for Vaccine Development

AbstractGene libraries have been constructed from the messenger ribonucleic acid (mRNA) isolated from venom glands of different poisonous animals such as snakes, scorpions, and snails. The gene banks thus created contain recombinant clones harboring DNA sequences encoding toxins with various pharmacological activities, ranging from myonecrosis-inducing to those affecting neuronal transmission. A number of these clones have been isolated and characterized, and gene expression has been attempted with limited success in Escherichia coli, baculovirus, and in two mammalian cell expression systems by using either cDNAs or synthetically-constructed genes.
Metabolism of 2,4,6‐trinitrotoluene by mixed microbial populations in digested sewage sludge under strict anaerobic conditions

Abstract TNT (2,4,6‐trinitrotoluene) was degraded effectively by a mixed microbial population in digested sewage culture under strict anaerobic conditions. An initial concentration of 110 mg/L of TNT was reduced to a non‐detectable amount (> 99 % removal) in 6 days of incubation. One remarkable intermediate, originating from TNT metabolism was eluted on HPLC chromatogram, and many transformed metabolites were detected by using mass spectrometry during metabolism. Four main metabolites were identified: 2‐hydroxylamino‐4,6‐dinitrotoluene and its isomer, 4‐hydroxylamino‐2,6‐dinitrotoluene; and 2‐amino‐4,6‐diinitrotoluene and its isomer, 4‐amino‐2,6‐dinitrotoluene. In the major reduction pathway, TNT transformed to 2‐amino‐4,6‐dinitrotoluene via 2‐hydroxylamino‐4,6‐dinitrotoluene by mixed microbial populations under strict anaerobic conditions. Due to the resistance of the transformed inhibitors, further stepwise deamination and subsequent mineralization by ring cleavage occurred by mixed specific reductase w...
Genetics of cytochrome P450 in two insecticide-resistant strains of the housefly, Musca domestica L.

A susceptible strain of Musca domestica containing visible mutant markers on chromosomes II, III, and V was crossed with multiresistant R-Fc and R-diazinon strains. F1 flies were backcrossed to the mutant parent, resultant progenies were isolated according to phenotype, and substrains were established. The level of resistance to diazinon, aldrin epoxidase activity, and cytochrome P450 difference spectra of microsomes from each substrain were measured. Titers of cytochrome P450, measured as CO spectra, as well as type I, type II, and type III cytochrome P450 substrate difference spectra were compared in microsomal preparations obtained from phenotypes containing vatious resistant chromosome combinations. In both resistant strains, high levels of cytochrome P450 were controlled by a gene(s) on chromosome II. In R-diazinon, qualitative spectral changes were also controlled by chromosome II, whereas in R-Fc both chromosomes II and V contributed to qualitative changes in cytochrome P450. Both quantitative and qualitative characteristics were intermediate in heterozygous flies, suggesting incomplete dominance for their inheritance. Findings are discussed in relation to known genetics of microsomal resistance to insecticides.
Determination of Basic α-Epoxides*

A common disadvantage of methods for determining basic epoxides or epoxides in the presence of a base is the necessity for determining a blank correction. A fast, direct method based on reaction with a standard solution of sodium thiosulfate is presented. The excess sodium thiosulfate is titrated with standard iodine solution. No blank correction is necessary. The stoichiometry of the reaction, the effect of temperature on the rate of reaction, precision, and other factors are described.
Garbage Collection in Chicago: A Dynamic Scheduling Model

We investigate the scheduling of garbage trucks in the city of Chicago. Analysis of data collected from the system shows that city blocks differ in the rate at which garbage is collected. However, in the current system, each truck visits the dumpsite two times each day. Our approach is to devise a flexible routing scheme in which some routes visit the dumpsite only once per day, while others visit the dumpsite twice per day depending on the blocks assigned to the route. We use a Markov decision process to model the impact on capacity of using flexible routes. This provides a dynamic scheduling algorithm that adjusts the number of dumpsite visits throughout the week to maximize service level. Results of the model suggest a potential reduction in truck capacity of 12-16% for a set of five pilot wards. This paper shows that flexible schedules can significantly reduce the capacity required to operate a system in the presence of variability.
Volatile compounds from thermally oxidized methyl oleate.

Thermal oxidation of methyl oleate was studied over a range of temperatures from 50 C to 150 C for periods of time up to 30 min. Degradation was quantitatively followed by gas liquid chromatography (GLC) and liquid scintillation counting of the products of methyl oleate-U-14C heated under a stream of compressed air. Heptane, octane, 2-decanone, benzene,o-xylene, methyl hexanoate, methyl heptanoate and methyl octanoate were identified by GLC and mass spectrometry. Mass spectral evidence also was obtained for methyl pimelaldehydate, methyl suberaldehydate and methyl azelaaldehydate. Organic synthesis confirmed the identity of methyl azelaaldehydate. Most of the products formed suggested that autoxidation was responsible for the degradation occurring at the temperatures employed in this study.
Afterschool physical activity program to reduce obesity-related cancer risk: a feasibility study.

Background. Cancer is linked to obesity, and Native Hawaiian childhood obesity rates are high. We examined the feasibility of incorporating a physical activity intervention into an afterschool program for elementary school children. Methods. Anthropometric and fitness measures were taken at baseline and 12 weeks later for 68 students in 2 schools. In one, the supervisor delivered a model curriculum. In the other, a supervisor with physical education training created the curriculum. Results. We found a significant decrease in skinfold thicknesses and increase in distance covered in the 3-minute walk-run test. Conclusions. Incorporating daily physical activity into afterschool programs is feasible and effective, but teacher interest is critical, and the nonmandatory nature of this venue may limit children’s participation.
The Dragged-Fovea Diplopia Syndrome : Clinical Characteristics, Diagnosis, and Treatment

Purpose To identify the clinical characteristics of the dragged-fovea diplopia syndrome, to introduce a simple diagnostic test that aids in the evaluation of such patients, and to provide a simple treatment option to improve the diplopia in some of these patients. Design Retrospective, observational case series. Participants Ninety-five affected eyes in 83 consecutive patients seen between January 1, 1993, and August 9, 2004, who were diagnosed with the dragged-fovea diplopia syndrome at one institution. Methods We reviewed the records of 222 patients who have been seen in the Krieger Children’s Eye Center at The Wilmer Institute since 1993 with a diagnosis of maculopathy, internal limiting membrane, or dragged fovea. We collected ocular findings and history for those patients who reported binocular diplopia that was not amenable to prism therapy and not secondary to acquired strabismus. Main Outcome Measures We recorded the presence of metamorphopsia on Amsler grid testing or other clinical evidence of macular wrinkling, response to prism trial, response to the small-field central fusion test (lights on-off test), and response to partial occlusion with Scotch Satin tape (3M Co., St. Paul, MN). Results Ninety-five affected eyes in 83 patients met the criteria for inclusion in the study. All patients who were tested with the lights on-off test (n = 69) responded positively, demonstrating rapid central fusion with room lights off, and recurrence of central diplopia with peripheral fusion with room lights on. Forty-six patients (of 64 tested) were receptive to monocular occlusion with Scotch Satin tape. Conclusions The dragged-fovea diplopia syndrome consists of central diplopia in the presence of peripheral fusion, secondary to dragging of the fovea in one or both eyes by retinal disease. The central diplopia cannot be eliminated by prism therapy or eye muscle surgery. The lights on-off test has proved pathognomonic for this syndrome, and many patients have benefited from partial monocular occlusion with Scotch Satin tape.
Multi-subnets selection and rate allocation in a heterogeneous wireless network

Heterogeneous wireless network (HWN) technology enables a mobile client (MC) to access multiple heterogeneous subnets for better quality of service (QoS) at a lower cost. In the context of conventional network protocol, we cannot fully utilize the potential of a HWN by having separate and independently operating subnet interfaces. In this paper, we propose a multi-MAC management scheme, performing multi-subnets selection and rate allocation over multiple heterogenous wireless interfaces for uplink traffic. Our scheme considers uplink traffic mixed by multiple applications with different QoS requirements and allocates appropriate data rates to multiple connections between MC and subnets. Extensive simulation results compare the performance and validate our scheme.
Ventricular fibrillation in pediatric cardiac arrest.

Objectives: After activating 9-1-1 for out-of-hospital cardiac arrest (CA), guidelines for children 1 year and older have evolved to include immediate automated external defibrillator (AED) use for witnessed arrest, and two minutes of cardiopulmonary resuscitation (CPR) followed by AED use for unwitnessed arrests. The best approach to resuscitation in a two-tiered emergency medical services (EMS) system depends in part on how likely the patient is to present with ventricular fibrillation (VF). Therefore, the authors evaluated the frequency of VF with respect to age and other characteristics to further elucidate the role of the AED among pediatric CAs. Methods: The investigation was a retrospective cohort study of EMS-treated, nontraumatic, out-of-hospital CA among persons aged 1–18 years in King County, Washington, between April 1, 1976, and December 31, 2003. The primary goal was to identify the proportion of patients presenting to EMS in VF, according to age. The association between other characteristics and the likelihood of VF was also evaluated. Finally, hospital survival according to cardiac rhythm at EMS arrival was evaluated. Results: Ventricular fibrillation was the presenting rhythm in 17.6% of cases (48/272). The proportion presenting with VF was 7.6% (10/131) among children aged 1–7 years and 27.0% (38/141) among children aged 8–18 years (p < 0.001). In multivariable models, VF was independently associated with age 8 years and older compared with 1–7 years (odds ratio, 3.19; 95% confidence interval [CI] = 1.46 to 6.97), witnessed arrest (odds ratio, 3.33; 95% CI = 1.63 to 6.82), and cardiac etiology (odds ratio, 2.89; 95% CI = 1.32 to 6.34). Survival was 31.3% (15/48) for VF and 10.7% (24/224) for nonshockable rhythm CAs. Conclusions: The proportion of children aged younger than 8 years presenting with VF is low compared with older children. The greatest increase in VF proportion occurs in children older than 12 years. Based on these results, the best approach for initial EMS resuscitation in a two-tiered EMS system, CPR versus AED use, is uncertain among younger children. Inclusion of witness status into the decision process for younger children may more efficiently allocate AED use, a finding in accordance with 2005 guidelines.
Unplugged Classrooms: Are Chalk‐talks Still in Play?

Distance Learning, Virtual Universities, Online Courses, and associated developments have received a lot of attention in this publication, academic educational journals, as well as the mainstream media. Most of the overviews tend to highlight the positive features of greater access, flexibility, reduced costs, and self‐paced learning. By 1999, over 10,000 accredited courses were being offered online, leading some commentators to declare the old‐fashioned classroom to be “as outdated as carbon paper and the mimeograph machine”. Although much of the optimism is related to the positive contributions which can supplement traditional “brick and mortar” colleges and universities, our techno‐fix culture has also created a “full speed ahead” rush towards computer‐mode education. “Like the stampede online by business, this is being propelled by a fear of being left behind – even though nobody really knows where we’re headed.”
Catalysis by Zn2+-metalloenzymes proceeds via a penta-coordinate metal-OH2 complex

Abstract The active site of a variety of metalloenzymes contains a catalytically essential tetra-coordinate Zn 2+ ion to which a water molecule is a ligand. It is generally assumed that the metal-bound water molecule has no role in catalysis. However, for both the native Zn 2+ - and Co 2+ -reconstituted forms of carboxypeptidase A (CPA) and liver alcohol dehydrogenase (LADH), we have identified metal ion dependent ionizations that govern steady state kinetic parameters and can be ascribed only to a metal-bond water molecule in catalytically competent reaction intermediates [1, 2]. To assign the coordination environment of the Co 2+ ion in these reaction intermediates, we have identified spectroscopic parameters of the high-spin Co 2+ ion that serve as a direct index of coordination number. Our studies [3] show on the basis of a group theoretical treatment of spin-orbit coupling, together with relationships derived through second-order perturbation theory, that the magnitude of the zero-field splitting (ZFS) of the high-spin Co 2+ ion is a direct monitor of crystal field symmetry and that it follows the order ZFS 4 5 6 where the subscript indicates the coordination number. Measurement of the ZFS in structurally defined coordination complexes confirms this relationship and indicates that the magnitude of 2| D | is 0–13 cm −1 for tetra-coordinate complexes, 20–60 cm 1 for penta-coordinate complexes, and 90–130 cm −1 for hexa-coordinate complexes. Application of this theory to measurements of the ZFS of CoCPA and CoLADH shows that the active site metal ion is tetra-coordinate in the free enzyme and is altered to a penta-coordinate complex in true reaction intermediates. In these intermediates the metal ion coordinates both the substrate and a water molecule simultaneously. Together with kinetic studies identifying ionizations of a metal-bound water molecule and showing that the reaction pathway is identical for Zn 2+ - and Co 2+ -enzymes, the results require that, upon formation of a penta-coordinate Zn 2+ OH 2 complex, breakdown of the acyl-enzyme (mixed anhydride) reaction intermediate of CPA occurs via metal-hydroxide nucleophilic attack on the carbonyl carbon of the scissile bond while in the physiologically active, ternary enzyme-NAD + - alcohol complex of LADH a neutral metal-bound water molecule serves as the base catalyst for proton abstraction. The results of these studies show that the metal-bound water has an integral catalytic role in CPA and LADH. It is probable that the metal-OH 2 complex has similarly a functional role in other Zn 2+ - metalloenzymes. (Supported by NIH grant GM 21900).
A molecular dynamics study of Cu dimer sputtering mechanisms

Molecular dynamics simulations were used to investigate the mechanisms responsible for the sputtering of dimers from Cu(100) and Cu(111) surfaces following bombardment by normally incident, 5 keV Ar^+ ions. Simulations were carried out using both a pair-potential and a many-body, embedded-atom potential to describe the Cu-Cu interaction. Computer animation techniques which allowed visual inspection of individual dimer trajectories were used to identify the mechanisms responsible for dimer ejection. In the pair-potential simulations dimers accounted for about 5% of the sputtering yield from both the (100) and (111) surfaces, while in the embedded-atom simulations dimers accounted for approximately 2% of the yield from the (100) and (111) surfaces. Three mechanisms were found to be responsible for the bulk of the dimer ejection events. Direct ejection of intact dimers and recombination in or near the surface were the most prevalent mechanisms observed. Less frequent, but still significant numbers of “push-stick” events were also seen. The simulations suggest that the sputtering of dimers is the result of competing mechanisms that take place preferentially towards the later phase of collision cascades that produce relatively large numbers of sputtered atoms.
Nicotinamide adenine dinucleotide phosphate oxidase in the formation of superoxide in osteoclasts.

Osteoclasts use a variety of chemical agents to degrade bone. One important component of this process is the generation of superoxide. It has been reported that nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is the enzyme responsible for superoxide production in phagocyte; however, the NADPH oxidase present in osteoclasts has not been studied in detail. One of the membrane-bound subunits of the NADPH oxidase is gp91phox which represents the rate-limiting component for the formation of the NADPH oxidase complex. This study was designed to demonstrate the presence of gp91phox in individual osteoclasts using the RT-PCR technique developed for limited numbers of cells. Compared with white cells, 1.8 times the amount of gp91phox mRNA was found in osteoclasts. This difference may be related to the size of the osteoclast and the multiple nuclei present. The presence of gp91phox in osteoclasts was confirmed at protein level by immunocytochemistry. Osteoclastic superoxide generation is inhibited by diphenylene iodonium, a specific inhibitor of the NADPH oxidase. These studies suggest that superoxide generation by osteoclasts correlates with the activity of NADPH oxidase.
Parental Education and Investment in Children’s Human Capital in Rural China

Abstract Numerous empirical studies from developing countries have noted that parental education has a robust and positive effect on child learning, a result that is often attributed to more educated parents making greater investments in their children’s human capital. However, the nature of any such investment has not been well understood. This study examines how parental education affects various parental investments in goods and time used in children’s human capital production via an unusually detailed survey from rural China. It is found that more educated parents make greater educational investments in both goods and time and that these relationships are generally robust to a rich set of controls. Evidence suggests that making greater investments in both goods and time stems both from higher expected returns to education for children and from different preferences for education among more educated parents. A second key finding is that the marginal effect of mother’s education on educational investmen...
Biogenic silica and chert in the Pacific Ocean

Evidence for the dissolution of biogenic silica at the base of pelagic sections supports the hypothesis that much of the chert formed in the Pacific derives from the dissolution and reprecipitation of this silica by hydrothermal waters. As ocean bottom waters flow into and through the crust, they become warmer. Initially they remain less saturated with respect to dissolved silica than pore water in the overlying sediments. With the diffusion of heat, dissolved ions, and to some extent the advection of water itself, biogenic silica in the basal part of the sedimentary section is dissolved. Upon conductively cooling, these pore waters precipitate chert layers. The most common thickness for the basal silica-free zone (20 m) lies below the most common height of the top of the chert interval above basement (50 m). This mode of chert formation explains the frequent occurrence of chert layers at very shallow subbottom depths in pelagic sections of the Pacific. It is also consistent with the common occurrence of cherts ≤150 m above basement.
Convergent method for calculating the properties of many interacting electrons

A method is presented for calculating binding energies and other properties of extended interacting systems using the projected density of transitions (PDoT) which is the probability distribution for transitions of different energies induced by a given localized operator, the operator on which the transitions are projected. It is shown that the transition contributing to the PDoT at each energy is the one which disturbs the system least, and so, by projecting on appropriate operators, the binding energies of equilibrium electronic states and the energies of their elementary excitations can be calculated. The PDoT may be expanded as a continued fraction by the recursion method, and as in other cases the continued fraction converges exponentially with the number of arithmetic operations, independent of the size of the system, in contrast to other numerical methods for which the number of operations increases with system size to maintain a given accuracy. These properties are illustrated with a calculation of the binding energies and zone-boundary spin- wave energies for an infinite spin-1/2 Heisenberg chain, which is compared with analytic results for this system and extrapolations from finite rings of spins.
A two-level iteration method for solution of contact problems

Abstract The merits and limitations of some existing procedures for the solution of contact problems, modeled by the finite element method, are examined. Based on the Lagrangian multiplier method, a partitioning scheme can be used to obtain a small system of equation for the Lagrange multipliers which is then solved by the conjugate gradient method. A two-level contact algorithm is employed which first linearizes the nonlinear contact problem to obtain a linear contact problem that is in turn solved by the Newton method. The performance of the algorithm compared to some existing procedures is demonstrated on some test problems.
Singlet and triplet states of an electron pair in a molecule : a simple model

Abstract The two-electron two-orbital model for the states of an electron pair is reformulated in terms of angular momentum operators for both the spin and the geminal space, taking advantage of the isomorphism of the two spaces. This unifying approach brings to light relations between apparently unrelated phenomena, such as the response of the triplet sublevels of an electron pair to the x, y, and z components of an external magnetic field, and the response of the singlet states of an electron pair in a perfect biradical to the covalent, magnetizing and polarizing perturbations by an external field or by molecular structure.
Commensurate and incommensurate vortex lattice melting in periodic pinning arrays

We examine the melting of commensurate and incommensurate vortex lattices interacting with square pinning arrays through the use of numerical simulations. For weak pinning strength in the commensurate case we observe an order-order transition from a commensurate square vortex lattice to a triangular floating solid phase as a function of temperature. This floating solid phase melts into a liquid at still higher temperature. For strong pinning there is only a single transition from the square pinned lattice to the liquid state. For strong pinning in the incommensurate case, we observe a multistage melting in which the interstitial vortices become mobile first, followed by the melting of the entire lattice, consistent with recent imaging experiments. The initial motion of vortices in the incommensurate phase occurs by an exchange process of interstitial vortices with vortices located at the pinning sites. We have also examined the vortex melting behavior for higher matching fields and find that a coexistence of a commensurate pinned vortex solid with an interstitial vortex liquid occurs while at higher temperatures the entire vortex lattice melts. For triangular arrays at incommensurate fields higher than the first matching field we observe that the initial vortex motion can occur through a correlated ring excitation where a number of vortices can rotate around a pinned vortex. We also discuss the relevance of our results to recent experiments of colloidal particles interacting with periodic trap arrays.
CD36 associates with CD9 and integrins on human blood platelets.

The membrane glycoprotein CD36 is involved in platelet aggregation, inhibition of angiogenesis, atherosclerosis, and sequestration of malaria-parasitized erythrocytes. In this study, immunoprecipitations with anti-CD36 antibodies were performed to identify proteins that associate with CD36 in the platelet membrane. Platelets were solubilized in 1% Triton X-100, 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), Brij 96, or Brij 99, and the proteins that coprecipitated with CD36 were identified by peptide mass spectrometry and Western blotting. The tetraspanin protein CD9 and the integrins αIIbβ3 and α6β1 specifically coprecipitated with CD36 from platelets that were solubilized in CHAPS and Brij 99 but not from platelets that were solubilized in Triton X-100. Only CD9 is coprecipitated with CD36 from platelets that were solubilized in Brij 96. Reciprocal immunoprecipitations with antibodies to CD9, α6, αIIb, or β3 from Brij 99–solubilized platelets coprecipitated CD36. Coprecipitation of CD36, CD9, and α6β1 was also observed on platelets from a patient with Glanzmann thrombasthenia, indicating that αIIbβ3 is not required for the other proteins to associate. Colocalization of α6 and CD36, of CD9 and CD36, and of α6 and CD9 was observed on intact platelets prior to solubilization, using double immunofluorescence microscopy. These data indicate that CD36 associates with CD9 and integrins on human blood platelets. These associated proteins may mediate or participate in some of the diverse biological functions of CD36.
Hemorrhagic Cystitis Caused by Acetic Acid Instillation

Direct intravesical instillation of acetic acid has been performed for the prevention and treatment of urinary tract infections in patients on bladder catheterization programs. The antibacterial action appears to be related to the acidification of bladder urine. Bladder irritation due to the low pH produced by acetic acid might be expected but a review of the literature did not reveal any reports of severe reactions due to bladder instillation of 0.25% acetic acid. We report an episode of hemorrhagic cystitis in a child caused by an error in the concentration of acetic acid solution used for intravesical administration. CASE REPORT R. W., an 11-year-old girl, had a history of myelomeningocele repair, ventriculoperitoneal shunt, neurogenic bladder, congenital agenesis of the right kidney, left vesicoureteral reflux repair and recurrent urinary tract infections. She was on a bladder regimen that included intermittent catheterization, intravesical oxybutynin and an oral suppressive antibiotic. After 2 weeks of receiving intravesical amphotericin B for candidal cystitis 0.25% acetic acid bladder instillations twice daily were initiated. The solution (15 ml.) was administered after catheterization and removed at the next catheterization. No side effects were noted for 6 weeks. The prescription was then refilled at a local pharmacy. Gross hematuria was noted after the third instillation and bladder irrigations were discontinued. It was discovered that 2.5% rather than 0.25% acetic acid had been dispensed. The urine remained bloody and catheter insertion was difficult for 36 hours. At that time the urine had 2+ protein and 3+ blood by dipstick, and the centrifuged sediment had innumerable red blood cells per high power field. Hematocrit was 40% (normal 35 to 45), total carbon dioxide was 17 mM.A. (normal 18 to 31) and other serum electrolytes were normal.
Histone deacetylase inhibitors: A review of their clinical status as antineoplastic agents

The histone code refers to specific modifications in the biochemical composition of nucleosome-associated histone proteins involved in the regulation of gene transcription. These modifications include, among several, acetylation, methylation, and phosphorylation of several histone amino acid residues and are associated with different states of chromatin configuration and gene expression. In particular, acetylation of specific residues in histones H3 and H4 has been associated with an open chromatin configuration and a permissive gene transcription state. This particular modification is regulated by several enzymatic activities with the capacity to either transfer acetyl groups or to induce histone deacetylation. This last activity is associated with gene silencing. Several agents have been shown to have histone deacetylase inhibitory activity (HDACI). In vitro, experiments in multiple neoplastic cancer cell lines have demonstrated that treatment with HDACIs results in increased global and gene specific histone acetylation, and reactivation of aberrantly silenced genes. This phenomenon has been associated with cell differentiation and induction of apoptosis. Based on these observations, several of these agents are now in clinical development both for solid tumor and hematological malignancies. In this article, we provide a brief introduction to the field of histone deacetylation inhibition in cancer and review the most relevant clinical data so far published.
Predicting Contraction Scour with a 2D Model

Contraction scour is often encountered in natural rivers due to channel contraction or river restoration structures. Such scour may be predicted better with multi-dimensional models than 1D models. It has been reported that the 2D depth-averaged model is inadequate for modeling the contraction scour. This study aims to investigate whether other factors may play important roles in the poor performance of 2D models. In the process, an improved prediction using the 2D model is obtained and factors influencing the model prediction are identified. The motivation of the study stems from the fact that a 3D model is too complex and many engineering applications have to rely on 2D models. This study shows that the 2D model is still adequate for predicting the contraction scour.