cssi/SciSciGPT-SciSciNet huggingface dataset:
Benzodiazepine and sedative-hypnotic use among older seriously Ill veterans: choosing wisely?

Abstract Purpose The 2014 American Geriatrics Society's Choosing Wisely list cautions against the use of any benzodiazepines or other sedative-hypnotics (BSHs) as initial treatments for agitation, insomnia, or delirium in older adults. Because these symptoms are prevalent among hospitalized patients, seriously ill older adults are at risk of receiving these potentially inappropriate medications. The objectives of this study were to understand the extent to which potentially inappropriate BSHs are being used in hospitalized, seriously ill, older veterans and to understand what clinical and sociodemographic characteristics are associated with potentially inappropriate BSH use. Methods We reviewed medical records of 222 veterans aged ≥65 years who were hospitalized in an acute care facility in the New York–New Jersey metropolitan region in fiscal years 2009 and 2010. Veterans had diagnoses of advanced cancer, chronic obstructive pulmonary disease, congestive heart failure, and/or HIV/AIDS and received inpatient palliative care. Associations among potentially inappropriate BSH use (BSHs for indications other than alcohol withdrawal and current generalized anxiety disorder or one-time use before a medical procedure) and clinical and sociodemographic characteristics were examined with multivariable logistic regression. Findings One-fifth of the sample was prescribed a potentially inappropriate BSH during the index hospitalization during the study period (n = 47). The most commonly prescribed potentially inappropriate medications were zolpidem (n = 26 [11.7%]) and lorazepam (n = 19 [8.9%]). Hispanic ethnicity was significantly associated with prescription of potentially inappropriate BSHs among the entire sample (adjusted odds ratio [AOR] = 3.79; 95% CI, 1.32–10.88) and among patients who survived until discharge (n = 164; AOR=5.28; 95% CI, 1.64–17.07). Among patients who survived until discharge, black patients were less likely to be prescribed potentially inappropriate BSHs than white patients (AOR = 0.35; 95% CI, 0.13–0.997), and patients who had past-year BSH prescriptions were more likely to be prescribed a potentially inappropriate BSH than patients without past-year BSH use. Implications The potentially inappropriate BSHs documented in our sample included short- and intermediate-acting benzodiazepines, medications that were not identified as potentially inappropriate for older adults until after these data were collected. Few long-acting benzodiazepines were recorded, suggesting that the older veterans in our sample were receiving medications according to the guidelines in place at the time of hospitalization. Clinicians may be able to reduce prescriptions of newly identified inappropriate BSHs by being aware of medications patients received before hospitalization and by being cognizant of racial/ethnic disparities in symptom management. Future studies should explore reasons for disparities in BSH prescriptions.
Vitamin B1 and B12 Uptake and Cycling by Plankton Communities in Coastal Ecosystems

While vitamin B12 has recently been shown to co-limit the growth of coastal phytoplankton assemblages, the cycling of B-vitamins in coastal ecosystems is poorly understood as planktonic uptake rates of vitamins B1 and B12 have never been quantified in tandem in any aquatic ecosystem. The goal of this study was to establish the relationships between plankton community composition, carbon fixation, and B-vitamin assimilation in two contrasting estuarine systems. We show that, although B-vitamin concentrations were low (pM), vitamin concentrations and uptake rates were higher within a more eutrophic estuary and that vitamin B12 uptake rates were significantly correlated with rates of primary production. Eutrophic sites hosted larger bacterial and picoplankton abundances with larger carbon normalized vitamin uptake rates. Although the >2 µm phytoplankton biomass was often dominated by groups with a high incidence of vitamin auxotrophy (dinoflagellates and diatoms), picoplankton (< 2 µm) were always responsible for the majority of B12-vitamin uptake. Multiple lines of evidence suggest that heterotrophic bacteria were the primary users of vitamins among the picoplankton during this study. Nutrient/vitamin amendment experiments demonstrated that, in the Summer and Fall, vitamin B12 occasionally limited or co-limited the accumulation of phytoplankton biomass together with nitrogen. Combined with prior studies, these findings suggest that picoplankton are the primary producers and users of B-vitamins in coastal ecosystems and that rapid uptake of B-vitamins by heterotrophic bacteria may sometimes deprive larger phytoplankton of these micronutrients and thus influence phytoplankton species succession.
Parallel contact detection algorithm for transient solid dynamics simulations using PRONTO3D

An efficient, scalable, parallel algorithm for treating material surface contacts in solid mechanics finite element programs has been implemented in a modular way for MIMD parallel computers. The serial contact detection algorithm that was developed previously for the transient dynamics finite element code PRONTO3D has been extended for use in parallel computation by devising a dynamic (adaptive) processor load balancing scheme.
ENVIRONMENT THROUGH A GENDERED LENS: FROM PERSON-IN- ENVIRONMENT TO WOMAN-IN-ENVIRONMENT

Building on interdisciplinary work by critical and feminist scholars in geography, architecture and urban planning, and history, this article proposes a reworking of social work's person-environment formulation to incorporate gender and its implications more fully. Three interlocking domains are addressed: (a) women's subjective experiences of their everyday environments; (b) the connections among these environmental experiences, the geography of women's lives, and larger social categories such as race/ethnicity, class, and sexual orientation; and (c) women's environmental strengths, resources, and agency. Reworking the politics of gender also means reimagining their geographies. --Massey (1994,p. 182) A focus on people in their environmental contexts is an essential, if not defining, feature of social work practice. This simultaneous commitment to person and environment is supported at all levels of the profession: in practice, in the professional literature, and in statements of the profession's purpose and mission (see, for example, DuBois & Miley, 1999; Hepworth, Rooney, & Larsen, 1997; or the preamble to the revised National Association of Social Workers [NASW] Code of Ethics [NASW, 1997]). Like many powerful and long-standing ideas, however, social work's person-environment formulation is ripe for reexamination. In this article, the author argues that social work's prevailing conceptualizations of person-environment relationships gloss over important differences in people's environmental experiences, particularly those based in key axes of social identity, such as race or ethnicity, class, gender, and sexual orientation. Furthermore, this tendency to assume universality in environmental experience is supported by understandings of the environment that afford too little attention to the dynamic interactions among environmental contexts, personal and cultural experiences, and larger sociopolitical arrangements. These arguments are presented from the perspective of women, whose particular
Deterring illegal downloading: the effects of threat appeals, past behavior, subjective norms, and attributions of harm

The study employs two experiments to examine the effectiveness of various strategies used to dissuade consumers from downloading music illegally. The research investigates two specific strategies that the recording industry has used: (1) fear or threat appeals (e.g., the threat of punishment, such as fines and/or jail time), and (2) attribution of harm (informing consumers of the harm caused by the illegal downloading of music, such as financial loss to either the artist or the recording company). The study also considers whether past illegal downloading behavior reduces the effectiveness of these disincentive strategies. Finally, the impact of subjective norms (i.e., whether subjects think their friends would approve of downloading music) was also investigated. A 3 (level of threat: low, moderate, or high) X 2 (who is harmed by illegal downloading: artist or recording company) experimental design was employed for study one. Undergraduate students (n = 388) participated in the study. Study two expanded on the design of the first study by adding a variable of subjective norms and by including previous downloading behavior in the model. Undergraduate students (n = 211) also participated in the second experiment. Findings indicate a significant effect of threat appeal such that stronger threat appeals were found to be more effective than weaker threat appeals in reducing illegal downloading. The first study also showed that prior illegal downloading behavior does not curtail the effects of threat appeals aimed at reducing illegal downloading. In addition, results reveal no differences in downloading behavior in terms of attribution of harm deterrent strategy (harm to either the recording artist or company). The most interesting finding from the second study is that subjective norms appear to equalize low versus high past downloaders, but only under conditions of weak fear. The current manuscript is the first to examine the impact of four different variables (threat appeals, attribution of harm, subjective norms, and previous downloading behavior) on subjects' likelihood to illegally download music in the future. In particular, this research illuminates the potential importance of social norms in discouraging a type of undesirable consumer behavior but shows that this occurs only under a restricted set of conditions: when threat is low and the consumer is not a habitually high downloader. It should be of interest to those in fields where intellectual property can be pirated on the Internet. Copyright © 2007 John Wiley & Sons, Ltd.
C-V profiling of steep dopant distributions

Abstract An exact expression for the incremental capacitance of a partially depleted n -channel with steep dopant gradient is given in terms of the position dependence of the peak electron concentration when the gate bias voltage is changed. The C-V concentration profile derived from this expression differs from the actual dopant profile in two respects: (i) The peak of the C-V profile for a heavily doped implant is about twice the peak dopant concentration, and lies somewhat closer to the depleting contact. This discrepancy arises from the gradual decay of the electron distribution into the depletion layer. (ii) The tail of the C-V profile extends far beyond the dopant profile. This discrepancy arises from the variation with applied voltage of the built-in potential between the position of peak electron concentration in the partially depleted channel and the bulk of the substrate. A procedure is given to reconstruct the actual dopant distribution from the tail of the C-V profile, a task for which the Kennedy method is found to be inadequate.
Generalizing database forensics

In this article we present refinements on previously proposed approaches to forensic analysis of database tampering. We significantly generalize the basic structure of these algorithms to admit new characterizations of the “where” axis of the corruption diagram. Specifically, we introduce page-based partitioning as well as attribute-based partitioning along with their associated corruption diagrams. We compare the structure of all the forensic analysis algorithms and discuss the various design choices available with respect to forensic analysis. We characterize the forensic cost of the newly introduced algorithms, compare their forensic cost, and give our recommendations.We then introduce a comprehensive taxonomy of the types of possible corruption events, along with an associated forensic analysis protocol that consolidates all extant forensic algorithms and the corresponding type(s) of corruption events they detect. The result is a generalization of these algorithms and an overarching characterization of the process of database forensic analysis, thus providing a context within the overall operation of a DBMS for all existing forensic analysis algorithms.
Comparison of solvent and microwave extracts of cranberry press cake on the inhibition of lipid oxidation in mechanically separated turkey

Cranberry press cake, an under utilized by-product of the cranberry processing industry is a potential source of food antioxidants. The objective of this research were (1) to prepare extracts from cranberry press cake using solvent extraction (SE) and microwave assisted solvent extraction (MASE), and (2) to test the ability of these extracts to inhibit lipid oxidation in mechanically separated turkey (MST). Water, ethanol and acetone were used as extraction solvents. Heating press cake prior to extraction with 70% ethanol increased antioxidant efficacy compared to extracting unheated press cake. Water extracts were least effective in inhibiting lipid oxidation. The most effective extracts were obtained by SE with 100% acetone or MASE with 100% ethanol. A poor correlation of 0.69 was obtained between the total phenols in the extracts and their ability to inhibit thiobarbituric acid reactive substances (TBARS) formation in MST. The correlation coefficient between the amount of quercetin in the extracts and the number of days of TBARS inhibition in MST was 0.87. This indicates that although quercetin may be good inhibitor of lipid oxidation, polyphenols other than quercetin are likely have a role in the inhibition of TBARS in MST. For a similar yield of the extracts, MASE extract using 100% ethanol was a better inhibitor than 100% ethanol SE extract of lipid oxidation in MST. In terms of choice of solvent, based on their flammability and toxicity, MASE with 100% ethanol would be a more likely a choice over SE with 100% acetone, for inhibiting oxidation in MST.
Mapping the Potential Energy Surfaces of the 1,6-Diphenyl-1,3,5-hexatriene Ground and Triplet States

The relative energies of the ground state isomers of 1,6-diphenyl-1,3,5-hexatriene (DPH) in benzene are determined from the temperature dependence of the equilibrium isomer composition obtained with the use of diphenyl diselenide as isomerization catalyst. In the triplet state, DPH exists as an equilibrium mixture of all-trans (ttt), trans,cis,trans (tct), cis,trans,trans (ctt), and cis,cis,trans (cct) isomers. Under degassed conditions, photoisomerization of the triplets is primarily bimolecular, involving a quantum chain process. Oxygen eliminates the quantum chain process by efficient deactivation of DPH triplets thereby revealing the triplet state isomeric composition. The temperature dependencies of the fluorenone-sensitized photoisomerization quantum yields and photostationary states for DPH in air-saturated benzene provide two independent measures of the temperature dependence of the equilibrium contribution of the isomeric triplets. They reveal the relative energies of the DPH triplet isomers. Tog...
Multiaperture ultrawideband SAR processing with polarimetric diversity

We describe an approach for the interpretation of ultra-wideband (UWB) synthetic aperture radar (SAR) imagery for object classification. The UWB sensor is used for detection of manmade objects, including those which are obscured by a forest canopy. An electromagnetic model is used to predict the backscatter received from the scene objects. We show that the 'early-time' (physical optics) portion of the backscatter is highly dependent on the object structure. Hence, backscatter from scene objects that differ in structure, such as vehicles and trees, have different sensitivity to aspect angle of the incident wave. Manmade objects exhibit specular reflections ar certain aspect angles while natural objects generally do not. Aspect- angle sensitivity of the backscatter is extracted by reconstructing the SAR image of an object over smaller subapertures of the full synthetic aperture. This multi-aperture approach provides important angular information while still maintaining detectable levels in the subsequent SAR images. However, this information alone cannot be used to accurately classify objects due to a limited range of aspect angles and an inhomogeneous obscuring media. Consequently, this information is combined with polarization information to establish a robust feature vector for object classification. These features are shown to be useful in detecting vehicles obscured by foliage. Results of our approach on real data are presented.
Sample size calculations for Bayesian prediction of bovine viral-diarrhoea-virus infection in beef herds

We used a Bayesian classification approach to predict the bovine viral-diarrhoea-virus infection status of a herd when the prevalence of persistently infected animals in such herds is very small (e.g. <1%). An example of the approach is presented using data on beef herds in Wyoming, USA. The approach uses past covariate information (serum-neutralization titres collected on animals in 16 herds) within a predictive model for classification of a future observable herd. Simulations to estimate misclassification probabilities for different misclassification costs and prevalences of infected herds can be used as a guide to the sample size needed for classification of a future herd.
Sync your data: update propagation for heterogeneous protein databases

The traditional model of bench (wet) chemistry in many life sciences domain is today actively complimented by computer-based discoveries utilizing the growing number of online data sources. A typical computer-based discovery scenario for many life scientists includes the creation of local caches of pertinent information from multiple online resources such as Swissprot [Nucleic Acid Res. 1(28), 45–48 (2000)], PIR [Nucleic Acids Res. 28(1), 41–44 (2000)], PDB [The Protein DataBank. Wiley, New York (2003)], to enable efficient data analysis. This local caching of data, however, exposes their research and eventual results to the problems of data staleness, that is, cached data may quickly be obsolete or incorrect, dependent on the updates that are made to the source data. This represents a significant challenge to the scientific community, forcing scientists to be continuously aware of the frequent changes made to public data sources, and more importantly aware of the potential effects on their own derived data sets during the course of their research. To address this significant challenge, in this paper we present an approach for handling update propagation between heterogeneous databases, guaranteeing data freshness for scientists irrespective of their choice of data source and its underlying data model or interface. We propose a middle-layer–based solution wherein first the change in the online data source is translated to a sequence of changes in the middle-layer; next each change in the middle-layer is propagated through an algebraic representation of the translation between the source and the target; and finally the net-change is translated to a set of changes that are then applied to the local cache. In this paper, we present our algebraic model that represents the mapping of the online resource to the local cache, as well as our adaptive propagation algorithm that can incrementally propagate both schema and data changes from the source to the cache in a data model independent manner. We present a case study based on a joint ongoing project with our collaborators in the Chemistry Department at UMass-Lowell to explicate our approach.
Performance And Control Of Proof-Mass Actuators Accounting For Stroke Saturation

We investigate the relationship between the parameters of a proof-mass actuator and the performance of that actuator within a vibration suppression loop for a flexible structure. We parameterize the model of the actuator in terms of the length of the proof-mass, the mass of the proof-mass, and the saturation force of the electromagnetic subsystem. The performance of the actuator within a vibration suppression control loop is characterized in terms of the relationship between the parameters and the structure's natural frequency. These results can be used to size a proof-mass actuator to maximize the operating region of the actuator and to maximize the ratio of the mass of the proof-mass to the total mass of the actuator .
Nonlinear electrochemical impedance spectroscopy for solid oxide fuel cell cathode materials

This paper reports initial studies of porous La0.8Sr0.2CoO3−δ electrodes on samaria-doped ceria using nonlinear electrochemical impedance spectroscopy (NLEIS). While traditional electrochemical impedance spectroscopy (EIS) involves measuring the linear response to small-amplitude potential or current perturbations, NLEIS probes both the linear and higher harmonic contributions to the potential upon excitation by a moderately sized current modulation. We find that these higher harmonic signals often contain specific resonant features that may help distinguish nonlinear physical processes governing the electrode reaction. Results are compared to preliminary models incorporating various possible rate-limiting phenomena, including solid-state diffusion and oxygen exchange at the gas/solid interface.
High cardiovascular risk in patients with diabetes and the cardiometabolic syndrome: mandate for statin therapy.

Diabetes mellitus confers a high risk of cardiovascular morbidity and mortality and requires aggressive management of all cardiovascular risk factors, including diabetic dyslipidemia. Although levels of low-density lipoprotein cholesterol are often normal or only slightly elevated in persons with diabetes, lipid-altering therapy with statins has been shown in large, randomized, controlled trials to decrease the risk of cardiovascular complications in this patient population. A target low-density lipoprotein cholesterol level of <70 mgldL is now a therapeutic option in patients at very high risk for coronary heart disease, including patients with diabetes. Diabetes is also a leading cause of end-stage renal disease. In addition to their lipid-modifying effects, statins have been shown to slow the progression of diabetic nephropathy and potentially exert other renoprotective effects; these benefits, however, remain to be confirmed in clinical trials.
Competitive factors and performance measurement: Applying the theory of constraints to meet customer needs

This article presents an analysis describing how the selection of proper competitive factors and modification to a firm's performance measurement system provide the means to control, coordinate and communicate product flow, from order receipt to customer shipment, through the production process. The article also discusses how modifications to the traditional manufacturing planning and control model to reflect the principles of the Theory of Constraints (TOC), along with the selection of proper competitive factors provide a means of synchronizing the production process to an ever-more demanding market. A performance measurement system that directs management's attention to the needs of the customers rather than to the internal concerns traditionally measured is advanced. A case study is included that characterizes the operation of an engineer-to-order manufacturing organization. This firm changed its competitive focus and its performance measurement system in response to a erratic sales pattern brought about by an inability to respond to customers requirements in terms of lead time and delivery promises. Using the principles advocated by TOC the organization was able to reduce lead time and improve delivery performance to a point where the operation became a preferred manufacturing location in the corporation. The cost measurement system was changed from a traditional standard cost system to a system utilizing TOC principles. A cost measurement system that measures global costs rather than individual component cost can also be a decisive factor in coordinating sales and manufacturing efforts within an organization. The relationship between these various factors is explored in the case study.
A phase II trial of talampanel in subjects with amyotrophic lateral sclerosis.

AbstractOur objective was to determine if chronic treatment with the non-competitive AMPA antagonist talampanel is efficacious and safe in subjects with ALS. A double-blind, placebo-controlled, multicenter, randomized clinical trial of nine months treatment duration was conducted in 59 subjects with ALS, with 40 subjects receiving talampanel 50 mg p.o. t.i.d, and 19 subjects receiving placebo. Primary outcome measure was rate of decline in isometric arm strength (as measured by change in arm strength megaslope of the Tufts Quantitative Neuromuscular Exam (TQNE)). Other efficacy endpoints included rate of decline in respiratory function, isometric leg strength, bulbar function, fine motor function, the ALS Functional Rating Scale (ALSFRS), and survival. Secondary safety outcome measures were frequency of adverse events, neurological status, plasma concentration of talampanel, vital signs, routine laboratory tests, and electrocardiograms. Decline in muscle strength was 15% less in talampanel treated subject...
In Vivo and in Vitro Analysis of Cardiac Troponin I Phosphorylation

Adrenergic stimulation induces positive changes in cardiac contractility and relaxation. Cardiac troponin I is phosphorylated at different sites by protein kinase A and protein kinase C, but the effects of these post-translational modifications on the rate and extent of contractility and relaxation during β-adrenergic stimulation in the intact animal remain obscure. To investigate the effect(s) of complete and chronic cTnI phosphorylation on cardiac function, we generated transgenic animals in which the five possible phosphorylation sites were replaced with aspartic acid, mimicking a constant state of complete phosphorylation (cTnI-AllP). We hypothesized that chronic and complete phosphorylation of cTnI might result in increased morbidity or mortality, but complete replacement with the transgenic protein was benign with no detectable pathology. To differentiate the effects of the different phosphorylation sites, we generated another mouse model, cTnI-PP, in which only the protein kinase A phosphorylation sites (Ser23/Ser24) were mutated to aspartic acid. In contrast to the cTnIAllP, the cTnI-PP mice showed enhanced diastolic function under basal conditions. The cTnI-PP animals also showed augmented relaxation and contraction at higher heart rates compared with the nontransgenic controls. Nuclear magnetic resonance amide proton/nitrogen chemical shift analysis of cardiac troponin C showed that, in the presence of cTnI-AllP and cTnI-PP, the N terminus exhibits a more closed conformation, respectively. The data show that protein kinase C phosphorylation of cTnI plays a dominant role in depressing contractility and exerts an antithetic role on the ability of protein kinase A to increase relaxation.
Region-specific stability of dendritic extent in normal human aging and regression in Alzheimer's disease. II. Subiculum

Abstract The dendritic trees of pyramidal neurons of layer III or the external pyramidal layer of the layer of the subiculum have been studied have been in Golgi Cox-stained human tissue obtained at autopsy. Fifteen cases were neurologically and psychiatrically normal and ranged in age from 43 to 95 years; and 5 cases had clinically and neuropathologically defined Alzheimer's disease (AD). Measures of dendritic extent did not change in normal aging in either the apical or basal trees. In AD there was a significant reduction in dendritic extent of the apical trees and a non-significant reduction in extent of the basal trees. These alterations of the dendritic trees in AD are consistent with the findings of severe pathology in the subiculum reported by others. Changes in AD were mainly a reduction in numbers of segments, rather than in the lenghts of segments.
Molar volumes in the homologous series of normal alkanes at two temperatures

Abstract Molar volumes of the n-alkanes C 5 , as obtained by vibrating tube densitometry, are reported at 288.15 and 298.15 K. The trend with carbon number is discussed.
Institutional determinants of saving: implications for low-income households and public policy

Abstract There is an emerging policy and academic discussion, supported by a growing body of empirical evidence, regarding the potentially positive effects of asset accumulation in low-income households. However, at least two questions precede this discussion: Can the poor save? And, if so, how can programs and policies promote saving by the poor? This paper begins to address these questions by examining the effects of institutional variables on saving behavior. We posit that four institutional variables—institutionalized saving mechanisms, targeted financial education, attractive saving incentives, and facilitation—promote saving. However, low-income households are substantially less likely to have access to these institutions, a phenomenon that may help explain their below-average saving rates. This discussion has implications, especially as policy-makers consider various proposals to increase the saving rates of low- and middle-income Americans.
Another look at An Inconvenient Truth

The portrayal of the science of climate change in An Inconvenient Truth is largely correct. Some aspects of the film, such as the discussion of Hurricane Katrina, oversimplify the complex factors involved, while others conflate global warming with other environmental changes that may not be related. However it is not in question that continuing emissions of greenhouse gases by human activities will cause greater climate change in the future, and that the impacts of such change are likely to be negative. The chief message of the film—that this fact places important moral and ethical choices before society—is therefore an accurate one.
Early postnatal development of GABAergic presynaptic inhibition of Ia proprioceptive afferent connections in mouse spinal cord

Sensory feedback is critical for normal locomotion and adaptation to external perturbations during movement. Feedback provided by group Ia afferents influences motor output both directly through mo...
DNA sequence encodes information for nucleosome array formation

We have examined the effects of base sequence on nucleosome array formation using randomly selected chicken genomic DNA sequences. DNA clones were assembled into chromatin under identical conditions using a defined in vitro system capable of generating physiologically spaced nucleosomes on some sequences. The nucleosome arrangements in native chromatin on the selected sequences were also examined in liver nuclei. Variations in nucleosome ladders were found among the different sequences that were similar in vitro and in nuclei. Differences in both the degree of regularity of nucleosome arrays and in the value of the nucleosome repeat length were observed. Analysis of an approximately 100 kilobase-pair contiguous region using cosmid clones suggested that well-ordered regions of chromatin, generally less than two kilobase-pairs in extent, alternate with less-ordered regions. This mosaic arrangement for chromatin organization appears to be largely a consequence of information encoded in the DNA base sequence. Nucleosome ordering with a 210 base-pair periodicity in a highly ordered ten-nucleosome array appeared to result from linker histone-dependent alignment with respect to each of two positioned nucleosomes, approximately 1000 base-pairs apart.
Sampling of carbonaceous particles in the atmosphere—II

Abstract A laboratory study was conducted to test the ability of various sorbents to remove vapor-phase atmospheric carbonaceous materials otherwise retained by sorption on quartz filters, a ‘positive artifact’ in sampling atmospheric particulate C. A dual quartz filter strategy, in which the C recovered from the after-filter is used to correct for the positive artifact, was also assessed. Sorbents such as activated Al2O3 and quartz fiber can reduce by up to 60% the positive artifact in sampling at 20 l min− with 47-mm Pallflex 2500 QAO quartz filters. On the assumption, defended herein, that a quartz fiber profilier was unlikely to influence the ratio of C retained by sorption on downstream tandem quartz filters, the dual filter strategy permitted correction for this positive artifact within, on average, 12%. Conclusions from an initial study suggesting extensive loss by volatilization of previously collected particulate C are reassessed.
Automatic pattern recognition by a Gestalt method

Signals representing coefficients in a series approximation to the two-dimensional density function represented by a pattern are directly measured by focusing an image of the pattern on a small number of weighted masks with a photocell behind each, or alternatively by passing the image of the pattern past a small number of weighted slits. The functions weighting the masks or slits are determined so as to enable subsequent normalization of the signals to make them independent of the incidentals of the configuration of the pattern; such incidentals may include variations in position, density, scale, orientation, and viewing perspective. Finally, recognition of a pattern is achieved by comparing the normalized signal values for an unknown pattern with sets of stored values representing known patterns; a “best match” of such values provides a basis for recognition of imperfect patterns in the presence of noise and measurement error. An example of one application of the method is discussed, as are the results of a computer simulation of a character reader based on the application.
Effect of surface ligands on optical and electronic spectra of semiconductor nanoclusters.

We investigate the impact of ligands on the morphology, electronic structure, and optical response of the Cd33Se33 cluster, which overlaps in size with the smallest synthesized CdSe nanocrystal quantum dots (QDs). Our density functional theory calculations demonstrate significant surface reorganization for both the bare cluster and the cluster capped with amine or phosphine oxide model ligands. We observe strong surface−ligand interactions leading to substantial charge redistribution and polarization effects on the surface. These effects result in the development of hybridized states, for which the electronic density is spread over the cluster and the ligands. The loss of one of the passivating ligands leads to either optically dark or bright additional states inside of the band gap, depending on the position of the leaving ligand on the QD surface. However, for fully ligated QDs, neither the ligand-localized nor hybridized molecular orbitals appear as trap states inside or near the band gap of the QD. In...
Methylmercury cycling in sediments on the continental shelf of southern New England

Abstract Exposure of humans to monomethylmercury (MMHg) occurs primarily through consumption of marine fish, yet there is limited understanding concerning the bioaccumulation and biogeochemistry of MMHg in the biologically productive coastal ocean. We examined the cycling of MMHg in sediments at three locations on the continental shelf of southern New England in September 2003. MMHg in surface sediments is related positively to inorganic Hg (Hg(II) = total Hg − MMHg), the geographical distribution of which is influenced by organic material. Organic matter also largely controls the sediment–water partitioning of Hg species and governs the availability of dissolved Hg(II) for methylation. Potential gross rates of MMHg production, assayed by experimental addition of 200 Hg to intact sediment cores, are correlated inversely with the distribution coefficient ( K D ) of Hg(II) and positively with the concentration of Hg(II), most probably as HgS 0 , in 0.2-μm filtered pore water of these low-sulfide deposits. Moreover, the efflux of dissolved MMHg to overlying water (i.e., net production at steady state) is correlated with the gross potential rate of MMHg production in surface sediments. These results suggest that the production and efflux of MMHg from coastal marine sediments is limited by Hg(II), loadings of which presumably are principally from atmospheric deposition to this region of the continental shelf. The estimated diffusive flux of MMHg from the shelf sediments averages 9 pmol m −2 d −1 . This flux is comparable to that required to sustain the current rate of MMHg accumulation by marine fish, and may be enhanced by the efflux of MMHg from near-shore deposits contaminated more substantially with anthropogenic Hg. Hence, production and subsequent mobilization of MMHg from sediments in the coastal zone may be a major source of MMHg to the ocean and marine biota, including fishes consumed by humans.
Evolution of Statistical Design and Analysis of Experiments

Abstract Changes in statistical thinking and improvements in methodology of designing experiments and analyzing data in the past quarter-century are highlighted in this article. Following a few introductory and historical comments are two major sections, one devoted to fundamental issues and controversies, the other to procedural developments. Future-oriented as scientists are prone to be, they should refrain from associating the merit of an idea with its propinquity. Perhaps more important to valid assessment of experimental results than any of the developments of the past two or three decades are the fundamental concepts of Fisher regarding the nature of experimental units, their replication and intimate association with experimental error, and the crucial role of randomization. To be abhorred are the propensities of scientists 1) to calculate standard errors as if variances were unequal when conclusions have been based on the assumption that they are equal, 2) to rely almost exclusively on "all-pairs" techniques for specific comparisions of means, and 3) to join the cult of " P or perish". Recent advances in analyses for categorical data, regression, mixed-model factorials, and repeated measurements are reviewed. In the future, additional emphasis is likely to be given to 1) response surface designs, 2) examination of data for validity of assumptions (via interactive computer systems), and 3) multivariate analysis of experiments with multiple responses to treatment.
Patterns of protein synthesis in dormant and growing vegetative buds of pea

Lateral buds on intact pea plants (Pisum sativum L. cv. Alaska) remain dormant until they are stimulated to develop by decapitating the terminal bud. Using two-dimensional gel electrophoresis, we have examined the protein content of terminal and lateral buds from intact plants and from plants at various times after decapitation. Silver-staining and in-vivo-labeling demonstrated very different sets of proteins. The level of expression of 18 stained and 25 labeled proteins was altered when growth was stimulated; this represents 3.4% and 9.1% of the total proteins detected by each method, respectively. Within 24 h of being stimulated, lateral buds doubled in length and their protein content was qualitatively nearly the same as that of terminal buds. Six hours after decapitation, before the onset of detectable growth, the overall pattern of protein synthesis in lateral buds was more like that of growing lateral buds or of terminal buds than that of dormant lateral buds. Direct application of N6-furfurylaminopurine (kinetin) to buds on intact plants stimulated their growth and resulted in the same pattern of protein synthesis as did decapitation. Inhibition of bud growth by addition of indole-3-acetic acid to the stumps of decapitated plants resulted in the synthesis of dormancy-related proteins. Lateral buds at all stages of development incorporated labeled amino acids at similar rates, indicating that metabolic activity is not a component of dormancy in these buds.
Relation of Precipitation and Temperature with Yield of Herbaceous Plants in Eastern Oregon

Eighteen years of herbage yields of range grasses and concomitant precipitation and temperature fluctuations were examined with correlation and regression techniques. Antecedent precipitation was the dominant factor influencing yield of perennial herbaceous species, while both temperature and precipitation were important for prediction of yield of downy bromegrass, a winter annual. Total yield of the herbaceous community was closely correlated with precipitation received during the September to June period (r = 0.92); however, September to March precipitation was also highly correlated (r = 0.89). These correlations provide timely and useful estimates of native range production on eastern Oregon ranges. Sixty to 92% of yield variation was accounted for by the regression models for 9 of the 12 species or species groups examined.
Intelligent information systems

Natural language processing techniques developed for Artificial Intelligence programs can aid in constructing powerful information retrieval systems in at least two areas. Automatic construction of new concepts allows a large body of information to be organized compactly and in a manner that allows a wide range of queries to be answered. Also, using natural language processing techniques to conceptually analyze the documents being stored in a system greatly expands the effectiveness of queries about given pieces of text. However, only robust conceptual analysis methods are adequate for such systems. This paper will discuss approaches to both concept learning, in the form of Generalization-Based Memory, and powerful, robust text processing achieved by Memory-Based Understanding. These techniques have been implemented in the computer systems IPP, a program that reads, remembers and generalizes from news stories about terrorism, and RESEARCHER, currently in the prototype stage, that operates in a very different domain (technical texts, patent abstracts in particular).
An optimal curtailment of a randomized ump test for a proprtion

Consider a fixed sample size UMP test of H0: p ≤ p0 versus H1: p > p0, where p is a Bernoulli parameter. If the test is non-randomized the optimal curtailed version is well-known. If the test is randomized, the decision of a UMP test is not uniquely determined. This paper considers the problem of curtailing such tests so that the expected number of observations is minimized. A simple complete characterization of such tests is given.
The common intersection of isotherms

Abstract It is shown that the common intersections of isotherms of RT — ( 1 2 ) PV recently described by Proost-Thoden van Velzen are in general only approximate, do not behave discontinuously as reported, are due to the near-linearity of P(T) isochors, and can be made more nearly exact for modified functions at certain densities.
Activity and Metabolism of 14C-(±)-Abscisic Acid Derivatives

Several radioactive analogues of abscisic acid have been tested for their growth-inhibitory effects and their metabolism in excised embryonic axes of Phaseolus vulgaris. The compounds tested were the methyl and ethyl esters of 2-14C-abscisic acid and the cis- and trans-1′,4′-diols of 2-14C-abscisic acid. All four compounds cause less growth inhibition than abscisic acid, and all four compounds are converted to abscisic acid in the axes at rates which are sufficient to account for most, if not all, of the observed growth-inhibitory activity. None of the four compounds is metabolized to the extent that abscisic acid is metabolized in the axes, suggesting that the structural requirements for growth-inhibitory activity and metabolism may be similar.
Differential binding of monoidinated insulins to muscle and liver derived receptors and activation of the receptor kinase

The binding affinity of monoiodoinsulin analogues to receptors purified from rat skeletal muscle and liver were compared. Insulin iodinated at tyrosine B26 bound to both muscle and liver derived insulin receptors with higher affinity than the A14-iodoisomer or native insulin. The affinity of the B26-iodoanalogue was greater for muscle than for liver derived receptors; by Scatchard analysis the affinity ratio B26/A14 was 2.8 for muscle and 1.3 for liver. The affinity of muscle and liver derived receptors for A14-iodoinsulin was not different. Dose response curves of autophosphorylation and exogenous tyrosine kinase activation showed significantly increased sensitivity to the B26-iodoanalogue (compared to the A14-iodoisomer or native insulin) in muscle derived receptors, but not in liver. The difference in affinity between muscle and liver derived insulin receptors towards B26-monoiodotyrosyl-insulin likely reflects the observed structural difference between the insulin receptor alpha-subunits from muscle and liver.
Studies of fs(1)1621, a mutation producing ovarian tumors in Drosophila melanogaster

The ethyl methane sulfonate-induced mutation, fs(1)1621, resides at 11.7 on the genetic map and within segment 4F1-5A1 of the cytological map of the X chromosome. When homozygous, fs(1)1621 renders females semisterile but has no effect on their viability; nor does it affect the viability or fertility of hemizygous males. Heterozygous females are fertile and have cytologically normal ovaries. The ovaries of homozygous females first produce normal oocytes, which, if fertilized, can develop into adult males or females. After this period, ovarian chambers containing only pseudonurse cells are formed, and finally mutant germaria produce only tumors. These contain hundreds to thousands of cells that appear to be derived from germarial cystocytes, because they occasionally form clones of interconnected cells and also can differentiate into endopolyploid pseudonurse cells. Raising the temperature speeds the rate at which tumors form; lowering it increases the probability of pseudonurse cell differentiation. Df(1)C159 includes fs(1)1621. The pattern of ovarian chamber production is more temperature sensitive in hemizygous females than in homozygous ones. The morphology of hemizygous tumors and the number of dividing cells within them also differ from homozygotes. These observations support the hypothesis that fs(1)1621 is producing a product, that less is produced by one gene than by two, and that the product plays a role in the mitosis and cytokinesis of ovarian cystocytes.
Studies on Phenolic Steroids in Human Subjects. V. Excretion of Urinary Estriol Glucosiduronate During Pregnancy

The excretion of urinary estriol glucosiduronate during 2 pregnancies was checked by the internal standard method using 16-14C-estriol-16α-β-d-glucopyranosiduronic acid. The latter had been previously biosynthesized. Daily values rose from 7 to 10 mg in the third month to 37 to 54 mg in the eighth month of pregnancy. These values are compared to those obtained by hydrolysis.
A new method for rapid collection of blood from rats.

Abstract Moderate amounts of blood were quickly collected from rats living in freely growing colonies by saphenous vein puncture.