cssi/SciSciGPT-SciSciNet huggingface dataset:
Tunable polarization mode conversion using thin-film lithium niobate ridge waveguide

Lithium niobate on insulator (LNOI) waveguides, as an emerging technology, have proven to offer a promising platform for integrated optics, due to their strong optical confinement comparable to silicon on insulator (SOI) waveguides, while possessing the versatile properties of lithium niobate, such as high electro-optic coefficients. In this paper, we show that mode hybridization, a phenomenon widely found in vertically asymmetric waveguides, can be efficiently modulated in an LNOI ridge waveguide by electro-optic effect, leading to a polarization mode converter with 97% efficiency. Moreover, the proposed device does not require tapering or periodic poling, thereby greatly simplifying the fabrication process. It can also be actively switched by external fields. Such a platform facilitates technological progress of photonics circuits and sensors.
Mining of Consumer Product Ingredient and Purchasing Data to Identify Potential Chemical Coexposures.

Background: Chemicals in consumer products are a major contributor to human chemical coexposures. Consumers purchase and use a wide variety of products containing potentially thousands of chemicals...
Ultrasound in Emergency MedicinePoint-of-Care Ultrasound (POCUS) for Isolated Pediatric Dysuria: An Unusual Presentation of Acute Appendicitis.

Abstract Background Isolated complaint of dysuria in an adolescent is a rare presentation for acute perforated appendicitis. Acute appendicitis typically involves vague periumbical pain that migrates to the right lower quadrant, associated with pain, nausea, and loss of appetite. There have been case reports of associated pyuria and dysuria in addition to classical symptoms, but to our knowledge, this is the first case with isolated dysuria presenting to an emergency department (ED). Case Report A 14-year-old boy presented to the ED with 3 days of dysuria and subsequent sensation of urinary retention. Urine dip showed occult blood without white cells or nitrites. A bedside renal/bladder point-of-care ultrasound (POCUS) did not show evidence of obstruction. However, it did reveal a retrovesicular fluid collection with an echogenic foci inside suspicious for abscess, likely secondary to ruptured appendicitis. This diagnosis was confirmed with a dedicated right lower quadrant ultrasound, with resultant treatment with i.v. antibiotics and eventual surgical resection of the appendix. Why Should an Emergency Physician Be Aware of This? Pediatric and adolescent patients may present with extremely atypical symptoms of a common disease process. In this case, early use of POCUS in the ED helped to quickly identify an acute surgical process and focus diagnostic and therapeutic interventions.
HPV-Impfung nach Therapie einer zervikalen intraepithelialen Neoplasie (CIN/HSIL)

Eine HPV(humane Papillomviren)-Impfung kann zuverlassig vor der Entstehung eines Zervixkarzinoms und seiner Vorstufen schutzen. Ob eine adjuvante HPV-Impfung die Rezidivrate nach Therapie senken kann, ist noch nicht vollstandig geklart Kann aus der bestehenden Datenlage ein Nutzen einer adjuvanten HPV-Impfung belegt werden? Auswertung und vergleichende Zusammenfassung dreier aktueller Metaanalysen zum Thema adjuvante HPV-Impfung nach operativer Therapie der CIN (zervikale intraepitheliale Neoplasie). Drei Metaanalysen belegen ubereinstimmend, dass die Rezidivrate mittels einer adjuvanten HPV-Impfung nach operativer Therapie einer CIN um ca. 65 % gesenkt werden kann. Etwa 2–3 % der adjuvant geimpften Frauen profitieren so von einer Impfung. Die „number needed to vaccinate“ liegt bei etwa 46. Eine adjuvante HPV-Impfung kann empfohlen werden.
A data management and publication workflow for a large-scale, heterogeneous sensor network

It is common for hydrology researchers to collect data using in situ sensors at high frequencies, for extended durations, and with spatial distributions that produce data volumes requiring infrastructure for data storage, management, and sharing. The availability and utility of these data in addressing scientific questions related to water availability, water quality, and natural disasters relies on effective cyberinfrastructure that facilitates transformation of raw sensor data into usable data products. It also depends on the ability of researchers to share and access the data in useable formats. In this paper, we describe a data management and publication workflow and software tools for research groups and sites conducting long-term monitoring using in situ sensors. Functionality includes the ability to track monitoring equipment inventory and events related to field maintenance. Linking this information to the observational data is imperative in ensuring the quality of sensor-based data products. We present these tools in the context of a case study for the innovative Urban Transitions and Aridregion Hydrosustainability (iUTAH) sensor network. The iUTAH monitoring network includes sensors at aquatic and terrestrial sites for continuous monitoring of common meteorological variables, snow accumulation and melt, soil moisture, surface water flow, and surface water quality. We present the overall workflow we have developed for effectively transferring data from field monitoring sites to ultimate end-users and describe the software tools we have deployed for storing, managing, and sharing the sensor data. These tools are all open source and available for others to use.
Color Tuning Dopants for Electrophosphorescent Devices: Efficient Blue Phosphorescence Pyrrazole and Carbene Complexes

In this paper, we describe several new Ir complexes for achieving efficient blue electrophosphorescence. The approach described here for achieving blue phosphorescence is to shift the cyclometallated ligand from phenyl-pyridine to either a phenyl pyrrazole or phenyl-imidazole. Both complexes emit strongly in the near UV, however, only the imidazole complex (carbene ligand) emits strongly at room temperature.
Killing the Goose That May Have Laid the Golden Egg: Only the Data Know Whether Sabotage Pays

A lively debate has developed concerning the incentive for a price-regulated input monopolist to engage in non-price discrimination if it vertically integrates into downstream markets. This paper identifies the key industry characteristics that determine whether such discrimination is likely, and studies both theoretically and numerically the tradeoffs among three important characteristics in the simplest extant model. The incentive to discriminate is theoretically ambiguous, but data for the US telecommunications industry indicate that discrimination is likely in the absence of policy-induced countervailing incentives. Countervailing policies include direct penalties for discriminatory behavior, forcing vertical autonomy, and fostering upstream competition.
A Computational Framework for Generating Sizing Function in Assembly Meshing

This paper proposes a framework for generating sizing function in meshing assemblies. Size control is crucial in obtaining a high-quality mesh with a reduced number of elements, which decreases computational time and memory use during mesh generation and analysis. This proposed framework is capable of generating a sizing function based on geometric and non-geometric factors that influence mesh size. The framework consists of a background octree grid for storing the sizing function, a set of source entities for providing sizing information based on geometric and non-geometric factors, and an interpolation module for calculating the sizing on the background octree grid using the source entities. Source entities are generated by performing a detailed systematic study to identify all the geometric factors of an assembly. Disconnected skeletons are extracted and used as tools to measure 3D-proximity and 2D-proximity, which are two of the geometric factors. Non-geometric factors such as user-defined size and pre-meshed entities that influence size are also addressed. The framework is effective in generating a variety of meshes of industry models with less computational cost.
An on-line computational model of human sentence interpretation

This dissertation presents a model of the human sentence interpretation process, which attempts to meet criteria of adequacy imposed by the different paradigms of sentence interpretation. These include the need to produce a high-level interpretation, to embed a linguistically motivated grammar, and to be compatible with psycholinguistic results on sentence processing. The model includes a theory of grammar called Construction-Based Interpretative Grammar (CIG) and an interpreter which uses the grammar to build an interpretation for single sentences. An implementation ofhte interpreter has been built called Sal. Sal is an on-line interpreter, reading words one at a time and updating a partial interpretation of the sentence after each constituent. This constituent-by-constituent interpretation is more fine-grained and hence more on-line than most previous models. Sal is strongly interactionist in using both bottom-up and top-down knowledge in an evidential manner to access a set of constructions to build interpretations. It uses a coherence-based selection mechanism to choose among these candidate interpretations, and allows temporary limited parallelism to handle local ambiguities. Sal''s architecture is consistent with a large number of psycholinguistic results. The interpreter embodies a number of strong claims about sentence processing. One claim is uniformity, with respect to both representation and process. In the grammar, a single kind of knowledge structure, the grammatical construction, is used to represent lexical, syntactic, idiomatic, and semantic knowledge. CIG thus does not distinguish between the lexicon, the idiom dictionary, the syntactic rule base, and the semantic rule base. Uniformity in processing means that there is no distinction between the lexical analyzer, the parser, and the semantic interpreter. Because these kinds of knowledge are represented uniformly, they can be accessed, integrated, and disambiguated by a single mechanism. A second claim the interpreter embodies is that sentence processing is fundamentally knowledge-intensive and expectation-based. The representation and integration of constructions uses many diverse types of linguistic knowledge. Similarly, the access of constructions is sensitive to top-down and bottom-up, syntactic and semantic knowledge, and the selection of constructions is based on coherence with grammatical knowledge and the interpretation.
Odontogenesis imperfecta. Report of a case.

Abstract An authentic case of odontogenesis imperfecta in a 7-year-old white girl has been discussed. The cause of the disease is not definitely known. No environmental factors could be linked with the anomaly. Similarly, no genetic background could be established from the limited data available.
Effective wet clean method to eliminate unwanted growth SiGe defect in FinFET

An effective wet clean method to remove unwanted growth SiGe defect in FinFET Junction sector was demonstrated in a single wafer clean toolset. The unwanted growth SiGe defect was known due to the tiny metallic particles (<10nm) from chemical sources in pre SiGe growth clean step. The new wet clean method can remove tiny metallic particles efficiently and obtain better surface particles performance on FinFET production wafers.
Management of anorectal symptoms associated with telaprevir.

PJP Based on my clinical experience with telaprevir (Incivek, Vertex), I would say that anorectal symptoms occur 25–30% of the time. The package insert for telaprevir cites a similar figure, reporting anorectal symptoms in 29% of telaprevir-treated patients compared to only 7% of patients treated with peginterferon and ribavirin. Overall, approximately one fourth of patients seem to experience some type of anorectal symptoms when treated with telaprevir.
Diversity Management Training Initiatives: A Profile of Current Practices Within the Lodging Industry

Abstract This study investigates diversity management training initiatives (DMTIs) currently practiced within the lodging industry. The results suggest that once an employee becomes involved in the diversity management training initiative, their perception of its importance increases. It was also concluded that the perceived impact of DMTIs is positive for both minority and non-minority employees. The findings support the notion that the lodging industry is operating in a very diverse environment. Thus, emphasizing communication and educational training initiatives while reiterating their importance to all involved is necessary for success.
Comparison of loop versus end ileostomy for fecal diversion after restorative proctocolectomy for ulcerative colitis.

Abstract Background: The goal of this study was to compare the benefits versus complications of temporary loop ileostomies and end ileostomies in a consecutive series of patients undergoing colectomy and ileal pouch-anal anastomosis for ulcerative colitis. Study Design: A retrospective review was performed of all patients undergoing restorative proctocolectomy with diverting ileostomy for ulcerative colitis at the UCLA Medical Center during a 4-year period. An end ileostomy (EI) was used for 38 patients and a loop ileostomy (LI) for 39. All patients had a J pouch, with all EI patients having a hand-sewn ileoanal anastomosis, and 33 LI patients having a double-stapled anal anastomosis. EI closure was performed through a laparotomy, and LI closure was performed through a periileostomy incision. Results: The mean operative time for EI closure was 157 minutes, and for LI closure was 103 minutes. The wound infection rate after EI closure was 5.3% and after LI was 10.3%. For EI patients, 2 of 38 patients required reoperation, compared with 5 of 39 for LI. The mean hospital stay after EI closure was 6.7 days, and after LI closure was 7.1 days. Peristomal skin irritation was more severe, more prolonged, and occurred in more than twice as many LI as EI patients. Home ostomy nurse care was necessary for a mean of two visits for EI patients and five visits for LI patients. The cost of ostomy supplies and care was more than double for LI patients compared with those with EI. Patient satisfaction and ability to resume physical and social activities early after ileostomy construction were much more favorable for EI than LI patients. Conclusions: The benefit of shorter operating time for LI closure compared with EI closure is often outweighed by the complications and costs of LI stomal care and patient dissatisfaction. EI should be considered more frequently for temporary ileal diversion after restorative proctocolectomy.
Using the blood concentration of 2,5-dimethylfuran as a marker for smoking

Correct analysis of whole blood volatile organic compounds (VOCs) in evaluating possible exposure situations requires differentiation of smokers from nonsmokers. Whole blood concentrations of 2,5-dimethylfuran are determined using an internal standard method, and the concentrations of this compound are evaluated as a marker for smoking in exposure-study subjects. Results indicate that the concentration of 2,5-dimethylfuran can be adequately determined in whole blood by a method already in use for determining VOCs in blood. The whole blood concentration of 2,5-dimethylfuran was an excellent predictor of smoking when compared with positive responses about smoking on questionnaires. Using a detection limit of 0.024 ppb, 2,5-dimethylfuran concentrations in blood correctly identified the smoking status of 96.4% of the subjects in this study. The blood 2,5-dimethylfuran concentration was linearly related to the number of cigarettes smoked per day. This method is advantageous since blood 2,5-dimethylfuran concentrations can be determined using the same method used to determine concentrations of other VOCs, thus obviating the need for additional analytical procedures.
CTCFBSDB 2.0: a database for CTCF-binding sites and genome organization

CTCF is a highly conserved transcriptional regulator protein that performs diverse functions such as regulating gene expression and organizing the 3D structure of the genome. Here, we describe recent updates to a database of CTCF-binding sites, CTCFBSDB (http://insulatordb.uthsc.edu/), which now contains almost 15 million CTCF-binding sequences in 10 species. Since the original publication of the database, studies of the 3D structure of the genome, such as those provided by Hi-C experiments, have suggested that CTCF plays an important role in mediating intra- and inter-chromosomal interactions. To reflect this important progress, we have integrated CTCF-binding sites with genomic topological domains defined using Hi-C data. Additionally, the updated database includes new features enabled by new CTCF-binding site data, including binding site occupancy and the ability to visualize overlapping CTCF-binding sites determined in separate experiments.
DNA polymerase V kinetics support the instructive nature of an oxidized abasic lesion in Escherichia coli.

Translesion synthesis past an oxidized abasic site, 2-deoxyribonolactone, in Escherichia coli results in high levels of dG incorporation and is dependent upon DNA polymerase V (Pol V). Kinetic expe...
Tethered surfaces: Statics and dynamics.

We apply renormalization-group and Monte Carlo methods to study the equilibrium conformations and dynamics of two-dimensional surfaces of fixed connectivity embedded in d dimensions, as exemplified by hard spheres tethered together by strings into a triangular net. A continuum description of the surfaces is obtained. Without self-avoidance, the radius of gyration increases as \ensuremath{\surd}lnL , where L is the linear size of the uncrumpled surface. The upper critical dimension of self-avoiding surfaces is infinite. Their radius of gyration grows as ${L}^{\ensuremath{\nu}}$, where Flory theory predicts \ensuremath{\nu}=4/(d+2), in agreement with our Monte Carlo result \ensuremath{\nu}=0.80\ifmmode\pm\else\textpm\fi{}0.05 in d=3. The Rouse relaxation time of a self-avoiding surface grows as ${L}^{3.6}$.
Easy-to-Compute Tensors With Symmetric Inverse Approximating Hencky Finite Strain and Its Rate

It is shown that there exist approximations of the Hencky (logarithmic) finite strain tensor of various degrees of accuracy, having the following characteristics: (1) The tensors are close enough to the Hencky strain tensor for most practical purposes and coincide with it up to the quadratic term of the Taylor series expansion; (2) are easy to compute (the spectral representation being unnecessary) ; and ( 3 ) exhibit tension-compression symmetry (i.e., the strain tensor of the inverse transformation is minus the original strain tensor). Furthermore, an additive decomposition of the proposed strain tensor into volumetric and deviatoric (isochoric) parts is given. The deviatoric part depends on the volume change, but this dependence is negligible for materials that are incapable of large volume changes. A general relationship between the rate of the approximate Hencky strain tensor and the deformation rate tensor can be easily established.
Adhesion improvement of diamond films on molybdenum rod substrates using metallic powder

Abstract The major problems with using wear-resistant diamond coatings in corresponding applications is poor adhesion of diamond to the surface of the substrate. The adhesion can be improved through the use of TiCu or Ni metallic powder as a binder material. A new seeding process using chemical vapor deposition (CVD) with d.c. plasma torches leads to diamond growth with desirable mechanical characteristics. The quality of the films is also found to correlate with the composition of the metallic powder. From cutting tests, we have found that such diamond films show strong adhesion to the substrate. This technique can be extended to processes of depositing diamond on steels and Co-bonded WC materials.
Ultrasonic wave propagation and attenuation in wet bone.

Abstract The propagation of ultrasonic longitudinal waves in bovine plexiform and human Haversian bone has been studied over the range 0.5–16 MHz. In wet bone little velocity dispersion was observed, in contrast to the results of earlier studies on dry bone. Large values of attenuation were observed.
Spray-Dried Iron Fischer−Tropsch Catalysts. 1. Effect of Structure on the Attrition Resistance of the Catalysts in the Calcined State

The use of Fe Fischer−Tropsch (F−T) catalysts in slurry bubble column reactors (SBCRs) has been problematic in the past because of their poor attrition resistance. Recently, we have reported the preparation of spray-dried Fe F−T catalysts having attrition resistance suitable for SBCR use, but the reason for this improvement was not clear. This paper focuses on research done to better understand the reason for the high attrition resistance of some of the Fe catalysts prepared. Understanding the relationship between the catalyst attrition resistance and composition/structure is important for the preparation of attrition-resistant Fe catalysts. In the present study, two series of spray-dried Fe F−T catalysts having the composition Fe/Cu/K/SiO2 but with different amounts of precipitated and/or binder SiO2 were investigated. All of the catalysts studied were evaluated in their calcined form. This was done to minimize any possible attrition due to Fe phase change (such as can occur during activation and F−T syn...
Amphipathic poly(ethylene glycol) 5000-stabilized dioleoylphosphatidylethanolamine liposomes accumulate in spleen

Relatively small liposomes (d < 200 nm) composed of dioleoylphosphatidylethanolamine (DOPE) and cholesterol (Chol) and containing dioleoyl-N-(monomethoxypoly(ethylene glycol)phosphatidylethanolamine (PEG-PE), with PEG of Mr 5000 (PEG5000-PE), accumulate in the spleen (∼40% i.v. injected dose), unlike dioleoylphosphatidylcholine (DOPC)/Chol/PEG5000-PE liposomes of similar size, which show prolonged circulation in the blood. Spleen accumulation was dependent on the injection dose, PEG-PE concentration, and the PEG chain length. The DOPE/Chol/PEG5000-PE liposomes are plasma stable and morphologically indistinguishable from DOPC/Chol/PEG5000-PE liposomes. These results reveal the significance of the matrix lipid in determining the circulation time of PEG-PE-containing liposomes, and are relevant to the design of liposomes which avoid or accumulate in the spleen.
A comparative study of the removal of heavy metal ions from water using a silica-polyamine composite and a polystyrene chelator resin

The maximum Cu(II), Ni(II), and Co(II) ion capacities of a silica-poly(ethyleneimine) composite (WP-1) are compared with those of the commercially available iminodiacetic acid chelator resin Amberlite IRC-718. Under batch (static) conditions, IRC-718 exhibits better capacities for these metals than WP-1. Dynamic studies, however, revealed that WP-1 possessed a much higher capacity for all three divalent metals than IRC-718, with relative metal capacities in the order CU(II) {gt} CO(II) {approximately} Ni(II). In the presence of the competing chelator ethylenediaminetetraacetic acid, the Cu(II) capacities of WP-1 and IRC-718 lost 48% and 45%, respectively, of their original adsorption values. Even with this decrease, however, WP-1 maintained a higher CU(II) capacity than IRC-718. Repeated cycle testing, using CU(II) solutions at both room temperature and 97 C, was conducted to compare the long-term stability of each material. WP-1 maintained 94% of its original Cu(II) capacity and maintained structural integrity after 3,000 cycles using room temperature copper solutions, while IRC-718 compressed and dropped to 64% of its original capacity. When boiling copper solutions were used, the capacity of WP-1 increased slightly over 1500 cycles, while IRC-718 lost 13% of its original copper capacity and again became compressed, indicating degradation of the polystyrene beads.
Internal pilots for observational studies.

Study planning often involves selecting an appropriate sample size. Power calculations require specifying an effect size and estimating "nuisance" parameters, e.g. the overall incidence of the outcome. For observational studies, an additional source of randomness must be estimated: the rate of the exposure. A poor estimate of any of these parameters will produce an erroneous sample size. Internal pilot (IP) designs reduce the risk of this error - leading to better resource utilization - by using revised estimates of the nuisance parameters at an interim stage to adjust the final sample size. In the clinical trials setting, where allocation to treatment groups is pre-determined, IP designs have been shown to achieve the targeted power without introducing substantial inflation of the type I error rate. It has not been demonstrated whether the same general conclusions hold in observational studies, where exposure-group membership cannot be controlled by the investigator. We extend the IP to observational settings. We demonstrate through simulations that implementing an IP, in which prevalence of the exposure can be re-estimated at an interim stage, helps ensure optimal power for observational research with little inflation of the type I error associated with the final data analysis.
Common Challenges and Problems in Clinical Trials of Boron Neutron Capture Therapy of Brain Tumors

Clinical trials for binary therapies, like boron neutron capture therapy (BNCT), pose a number of unique problems and challenges in design, performance, and interpretation of results. In neutron beam development, different groups use different optimization parameters, resulting in beams being considerably different from each other. The design, development, testing, execution of patient pharmacokinetics and the evaluation of results from these studies differ widely. Finally, the clinical trials involving patient treatments vary in many aspects such as their dose escalation strategies, treatment planning methodologies, and the reporting of data. The implications of these differences in the data accrued from these trials are discussed. The BNCT community needs to standardize each aspect of the design, implementation, and reporting of clinical trials so that the data can be used meaningfully.
Infrared and Raman spectra of difluoromalononitrile: Vibrational assignment, normal coordinate analysis and thermodynamic functions☆

Abstract The infrared and Raman spectra of difluoromalononitrile [CF2(CN)2] are reported from 200–4000 cm−1. Complete vibrational assignments and normal coordinate analysis are reported and statistical thermodynamic functions calculated. The shift of the CN stretching frequency relative to its value in CF3CN is correlated with the effective electronegativity of X atoms in the acetonitrile structure.
Sex differences in cytokine responses to myelin peptides in multiple sclerosis

Abstract Many autoimmune diseases preferentially affect women; however, the underlying mechanisms for the sex differences are poorly understood. We examined sex-dependent differences in the immunologic response to myelin proteins in 22 multiple sclerosis (MS) patients and 22 healthy controls. Using ELISA spot assay (ELISPOT) methodology, interferon (IFN) γ and IL-5 secretions were examined at the single cell level in response to overlapping proteolipid protein (PLP) peptides. As previously reported, we observed an overall disease effect in the IFNγ response, such that MS patients were significantly higher than controls. With respect to PLP-induced IFNγ secretion, both MS and control females responded higher than their corresponding males. Female MS patients demonstrated the highest responses compared to MS males or healthy controls of either sex. Although MS females had high IFNγ responses to PLP, they had no IL-5 responses at all, suggesting strong Th1 skewing. In contrast, MS males had more IL-5 than control males, who lacked IL-5 responses. These IL-5 responses suggested that disease and gender are not independent, but rather interact to influence the cytokine response to myelin. The data suggest a gender bias towards Th1 responses in MS, which may contribute to the female predominance in this disease.
Mechanistic Studies Examining the Efficiency and Fidelity of DNA Synthesis by the 3TC-Resistant Mutant (184V) of HIV-1 Reverse Transcriptase†

A single amino acid substitution from methionine-184 to valine (M184V) of HIV-1 reverse transcriptase (RT) evokes the 1000-fold 3TC (Lamivudine) resistance by the HIV-1 virus observed in the clinic. The M184V mutant HIV-1 RT was studied to assess its catalytic efficiency during single nucleotide incorporation using a transient kinetic approach. The maximum rate of polymerization (k(pol)), binding affinity (K(d)), and incorporation efficiency (k(pol)/K(d)) were determined for incorporating dCTP and 3TC-TP by wild-type and 3TC-resistant HIV-1 RT. The 3TC-resistant HIV-1 RT showed a similar efficiency of incorporation compared with the wild-type enzyme during DNA-dependent DNA polymerization; however, the incorporation efficiency is reduced 3.5-fold during RNA-dependent polymerization. A dramatic 146- and 117-fold decrease in incorporation efficiency was observed for 3TC-MP incorporation by M184V RT for DNA- and RNA-dependent DNA polymerization, respectively, as compared with wild-type HIV-1 RT. While the k(pol) was slower and the K(d) was weaker for 3TC-TP incorporation by the M184V RT, the decrease in the efficiency of incorporation is primarily due to a substantially reduced binding affinity for the 3TC-TP to the enzyme.DNA (or RNA) complex poised for DNA elongation. The fidelity of M184V RT was also examined to evaluate mispair formation since this mutant has been suggested to exhibit a higher level of fidelity. The results of our studies indicate that there is a maximum 2.4-fold increase in fidelity for M184V RT as compared with wild-type HIV-1 RT. Both the wild-type and 3TC-resistant mutant RT showed higher fidelity using an RNA template as contrasted with the corresponding DNA template. This mechanistic information provides insight into our understanding of the molecular mechanism of 3TC-drug resistance and supports suggestions that increased RT fidelity and decreased fitness of the M184V HIV-1 virus may be factors contributing to the strong antiviral effect of AZT-3TC combination therapy.
D/H ratios of environmental water recorded by D/H ratios of plant lipids

Isotope ratios of chemical components are powerful tools in the interpretation of palaeoenvironments, particularly carbonates from foraminiferans1,2, desert caliche3, and desert pavements4. Isotope ratios of plant cellulose are also indicators of environmental variables such as temperature and relative humidity5–7. Several workers have reported climatic fluctuations based on hydrogen and oxygen isotope ratios of cellulose from tree trunks8–10 and peats11,12. Here I present measurements that demonstrate that for submerged aquatic plants δD values of lipids record D/H ratios of environmental water, whereas cellulose does not. I further demonstrate that δD values of lipids in conjunction with δ18O values of cellulose provide significant information on isotope ratios of environmental water.
Age, Family, and Migration in Nineteenth-Century Black Sea Provinces of the Ottoman Empire

Although contemporary Europeans often stated that the Ottoman government kept no population statistics, the Ottomans in fact often kept very detailed population records. The Ottoman ‘censuses’ recently used in scholarly research are only general summaries of population. More exact demographic research demands information on demographic structure, such as age, sex, and family affiliation. Since general ‘censuses’ are useless for such analysis, population registers ( nufus defterleri ) must be used.
Aqueous diffusion through partition membranes

Diffusion data obtained from Leonard-Bluemle cell was interpreted in terms of the extent of interaction between solute and membrane matrix. A new equation was developed to provide linear fit curve for the half-time data measurements. To develop an understanding of these partition type membranes on the molecular basis, the absolute reaction rate theory has been explored.
Long-term effects of a lock and dam and greentree reservoir management on a bottomland hardwood forest.

Abstract We investigated the long-term effects of a lock and dam and greentree reservoir management on a riparian bottomland hardwood forest in southern Arkansas, USA, by monitoring stress, mortality, and regeneration of bottomland hardwood trees in 53 permanent sampling plots from 1987–1995. The lock and dam and greentree reservoir management have altered the timing, depth, and duration of flooding within the wetland forest. Evaluation of daily river stage data indicates that November overbank flooding (i.e. 0.3 m above normal pool) of 1 week duration occurred only 10 times from 1950 to 1995 and four of these occurrences were the result of artificial flooding of the greentree reservoir. Results of the vegetation study indicate that the five most common dominant and co-dominant species were overcup oak, water hickory, Nuttall oak, willow oak, and sweetgum. Mortality of willow oak exceeded that of all other species except Nuttall oak. Nuttall oak, willow oak, and water hickory had much higher percentages of dead trees concentrated within the dominant and co-dominant crown classes. Probit analysis indicated that differences in stress and mortality were due to a combination of flooding and stand competition. Overcup oak appears to exhibit very little stress regardless of crown class and elevation and, with few exceptions, had a significantly greater probability of occurring within lower stress classes than any other species. Only 22 new stems were recruited into the 5 cm diameter-at-breast height size class between 1990–1995 and of these, three were Nuttall oak, three were water hickory, and one was sweetgum. No recruitment into the 5 cm diameter-at-breast height size class occurred for overcup oak or willow oak. The results of the study suggest that the forest is progressing to a more water-tolerant community dominated by overcup oak. A conservative flooding strategy would minimize tree stress and maintain quality wildlife habitat within the forested wetland.
A 2.2GHz-80dBΩ CMOS receiver front-end for short-range optical communication employing DMT/OFDM

This paper presents a novel receiver architecture for short-range optical communications using advanced modulation schemes in deep submicron CMOS technology. A prototype design including a 270×270 μm 2 integrated photodiode interfaced with an ultra-low impedance transimpedance amplifier (TIA) and a continuous time linear equalizer (CTLE) is simulated in IBM 0.13 μm CMOS technology. To demonstrate the flexibility of the proposed design, simulation results for both on-off-keying (OOK) and 64-QAM baseband orthogonal frequency division multiplexed (OFDM) data are presented. With 40 mW power dissipation from a 1.2 V supply and an estimated 15 pF photodiode capacitance, binary modulation data rate of 3.2 Gbps with a sensitivity of -6.7dBm (BER=10 -12 ) is achieved in post layout simulations. In the multi carrier modulation scenario, the receiver achieves a multi-tone power ratio (MTPR) of 28 dBc maintaining 200mV peak-to-peak output voltage for an input signal peak-to-average ratio (PAR) of 4.8dB. The received constellation shows minimal scattering due to the amplifier non-linearity.
Antithrombin concentrates use in children on extracorporeal membrane oxygenation: a retrospective cohort study.

Objective:To investigate whether receipt of any antithrombin concentrate improves laboratory and clinical outcomes in children undergoing extracorporeal membrane oxygenation for respiratory failure during their hospitalization compared with those who did not receive antithrombin.Design:Retrospective
Phase I study of 4′-deoxydoxorubicin (esorubicin) in children with malignant solid tumors

4′ -Deoxydoxorubicin was given to 15 patients with drug-resistant pediatric malignant solid tumors with the objectives of determining the maximum tolerated dosage and dose-limiting toxicity. Maximum tolerated dosage was 36 mg/m2 given IV once every 3 weeks. Dose limiting toxicity was myelosuppression, which was severe and prolonged. Therapeutic benefits were not observed for these patients.
NMDA receptor subunit composition controls synaptogenesis and synapse stabilization

During early postnatal development in the rat hippocampus, synaptogenesis occurs in parallel with a developmental switch in the subunit composition of NMDA receptors from NR2B to NR2A. It is unclear how this switch affects the process of synaptogenesis, synapse maturation, and synapse stabilization. We investigated the role of NR2 subunits in synaptogenesis during the period in which expression and synaptic incorporation of the NR2A protein begins through the time when it reaches adult levels. We found that early expression of NR2A in organotypic hippocampal slices reduces the number of synapses and the volume and dynamics of spines. In contrast, overexpression of NR2B does not affect the normal number and growth of synapses; however, it does increase spine motility, adding and retracting spines at a higher rate. The C terminus of NR2B, and specifically its ability to bind CaMKII, is sufficient to allow proper synapse formation and maturation. Conversely, the C terminus of NR2A was sufficient to stop the development of synapse number and spine growth. Our results indicate that the ratio of synaptic NR2B over NR2A controls spine motility and synaptogenesis, and suggest a structural role for the intracellular C terminus of NR2 in recruiting the signaling and scaffolding molecules necessary for proper synaptogenesis.
Thermodynamics of the S = {3}/{2} Coqblin-schrieffer model in a magnetic field: Comparison with experiments on Ce in LaB 6

Abstract The magnetization, specific heat and entropy of the Coqblin-Schrieffer model for S = 3/2 in the presence of a magnetic field, obtained previously by solving numerically the thermodynamic Bethe-ansatz equations, are compared to recent experiments on Ce impurities in LaB6, where the cubic crystal field is believed to lead to a Г8 ground-multiplet. Discrepancies are attributed to a splitting of the Г8-quartet.
Mechanisms of atrial fibrillation : Lessons from studies in patients

Recent clinical studies performed in human subjects have provided important clues that improved our understanding of the mechanisms of atrial fibrillation (AF) and facilitated development of new treatment strategies. When analyzed together, these studies confirm the complexity and multifactorial nature of AF. Because a variety of mechanisms such as focal drivers within the thoracic veins, rotors in the left atrium, multiple reentrant circuits, and autonomic innervation may play a role in the initiation and maintenance of AF alone or in combination, the best strategy to eliminate AF may be the accurate identification of one or more of the mechanisms critical to the genesis of AF and to target the specific mechanism(s).
Brook trout (Salvelinus fontinalis) population dynamics and mottled sculpin (Cottus bairdi) occurrence in relation to acidic episodes in streams

We monitored water chemistry and populations of brook trout (Salvelinus fontinalis) and mottled sculpins (Cottus bairdi) in 5 streams and some tributaries to determine how the severity of acidic episodes (low pH and high Al) influenced density and distribution of these species. Among streams, Linn Run had the lowest pH (4.8) and highest concentrations of total dissolved Al (>400 μg-l−1) during periods of high discharge. Densities of brook trout and mottled sculpins were low in Linn Run, but high in tributaries, where pH (6.5) and Al (30 μg-l−1) remained well below lethal levels. Among the other streams, brook trout density was highest where the acidic episodes were least severe and the density of age-0 brook trout was lowest when precipitation during the early months of the year was above normal. Immigration of brook trout from downstream areas maintained populations in the stream segments subjected to severe episodes. Mottled sculpins were not found in streams with severe episodes.
The role of ErbB receptor signaling in cell fate decisions by cortical progenitors: evidence for a biased, lineage-based responsiveness to different ligands.

Abstract We recently identified the required collaborative signaling of TGFα and collagen type IV to regulate cell fate choice in the cerebral cortex, measured by the expression of the limbic system associated membrane protein (LAMP) by nonlimbic, sensorimotor progenitors. We show that activation of different members of the erbB receptor family can similarly modulate the specification of cortical area fate. The region of the cerebral wall from which progenitor cells arise does not influence the response to the neuregulin-1 or TGFα, but a subpopulation of progenitors is not competent to express LAMP in response to neuregulin-1. The heterogeneity in the responsiveness by progenitors to the two growth factors is reflected in the expression of different repertoires of erbB receptors. Using clonal analysis, we demonstrate that there may be a lineage-dependent mechanism regulating the ability of neuronal progenitors to respond to specific inductive cues that control cell fate.
Mercuric ion-catalyzed hydration of derivatives of 1,4-dichloro-2-butyne. Hydration of 1-aryloxy-4-arylthio-2-butynes, 1,4-bis(arylthio)-2-butynes, and 1,4-bis(arylsulfonyl)-1-butynes

The mercuric ion-catalyzed hydration of 1,4-bis(arylthio)-2-butynes and 1-aryloxy-4-arylthio-2-butynes was studied. The 1,4-bis(arylsulfonyl)-2-butynes afforded 1,4-bis(arylsulfonyl)-2-butanones (7). The 1,4-bis(arylthio)-2-butynes afforded a variety of products in acetic acid among which were: 1,4-bis(arylthiomethyl)vinyl acetate (18); 1,4-bis(arylthio)-2-butanone (15); 1-(arylthio)-3-buten-2-one (16); and 1-(arylthio)-4-acetoxy-2-butanone (17). Ketone 15 eliminates arylthiol in an acidic medium yielding 16 which undergoes Michael addition of solvent to give 17. Treatment of 7 with base in the presence of a nucleophile (ArSH) analogously leads to elimination of arylsulfinic acid, followed by Michael addition of arylthiol. Hydration of 5 in methanol cleanly gave 1-(arylthio)-4-methoxy-2-butanones (19). In contrast, 1-aryloxy-4-arylthio-24)utynes afforded chromenes (8) by intramolecular cyclization. No thiochromenes were formed in any of the examples investigated.
Surface composition and erosion yields for CVD TiB2 films subjected to low energy deuterium ion bombardment

Abstract The surface composition and low energy sputter yield of deuterium bombarded CVD TiB2 films have been measured. The sputter yield increases with energy up to 1 keV where it reaches a maximum of 0.024 atoms/ion. Above 1 keV the yield decreases due to ion penetration effects. Surface composition measurements using Auger, X-ray photoelectron and secondary ion mass spectroscopies show that a surface layer about 200 A thick is depleted in B during 2 keV deuterium bombardment. This effect is attributed to preferential sputtering. Oxides and deuterides of titanium are also observed on the deuterium bombarded TiB2 surface.
MATERIAL PROCESSING VIA AN INTEGRATED MECHANICAL AND THERMAL ACTIVATION PROCESS

This paper reviews the recent progress in material synthesis and processing based on mechanical activation approaches. Material processing based on mechanical alloying and attrition has been widely used to prepare metastable phases, amorphous alloys, composites, and nanostructured materials. The most recent progress made in mechanical activation is the development of a new process that integrates mechanical activation and thermal activation to produce novel materials as well as conventional materials. The integrated mechanical and thermal activation (IMTA) process represents one of the most exciting recent advancements and holds great promise for commercial viability. Examples of enhanced reaction rates and synthesis of nanocrystalline materials are provided to illustrate the progress brought about by the IMTA process.
Musical Understanding, Musical Works, and Emotional Expression: Implications for Education.

What do musicians, critics, and listeners mean when they use emotion‐words to describe a piece of instrumental music? How can ‘pure’ musical sounds ‘express’ emotions such as joyfulness, sadness, anguish, optimism, and anger? Sounds are not living organisms; sounds cannot feel emotions. Yet many people around the world believe they hear emotions in sounds and/or feel the emotions expressed by musical patterns. Is there a reasonable explanation for this dilemma? These issues gain additional importance when we ask them in the context of music education. For example, can we, or should we, teach music students to listen‐for musical expressions of emotion? If so, how? My contention is that listeners can and do hear emotions in musical patterns; musical sounds can be expressive of emotions. Accordingly, I offer ideas for teaching students how to hear and create musical expressions of emotions.
Monitoring Insecticide Resistance in Liriomyza trifolii (Diptera: Agromyzidae) with Yellow Sticky Cards

The use of commercially available yellow sticky cards coated with thin layers of insecticide-sticker mixtures as a bioassay was explored to determine insecticide resistance in adult Liriomyza trifolii (Burgess). Young flies emerging from celery or chrysanthemum foliage collected in the field were captured on sticky cards treated with various amounts of permethrin or chlorpyrifos. The control included no insecticide. Mortality of the flies was used to estimate the degree of resistance of a given population to these insecticides. Duration of exposure to insecticide before mortality evaluation was standardized at 24 h. Control mortality increased with increasing amounts of sticker on the cards and with increasing adult age. Males were slightly more susceptible to both insecticides than females, and small flies were slightly more susceptible to permethrin than large flies.Dose-mortality estimates produced by the sticky card procedure are comparable with those produced by a topical application bioassay. The sticky card bioassay is a simple procedure that is accurate, repeatable, and usable for field or greenhouse populations.
Focus Issue: Coping with Cellular Stress

Organisms constantly face potential damage from internal and external sources, thus necessitating signaling cascades that couple specific cellular stresses to the appropriate responses. This Focus Issue of Science Signaling highlights the signaling pathways that are activated by and that mediate responses to diverse types of stresses.
Nonlinear Parameters for Granular Base Materials from Plate Tests

Repeated load triaxial tests are widely used to determine nonlinear behavior of unbound granular materials. However, conventional triaxial specimen preparation techniques may not be able to reconstruct the internal structure of a material which has great impact on some of the nonlinear parameters. In addition, it is difficult to reproduce in situ stress conditions in a triaxial cell. In this study, full-scale cyclic and static laboratory plate load tests were performed to investigate the mechanical properties of unbound granular materials. An algorithm was developed to backcalculate nonlinear parameters for prediction of models as a function of bulk stress. Study results demonstrate the pronounced influence of water content on the behavior of unbound granular materials and a generally linear relation between nonlinear parameter K1 and the degree of saturation.