cssi/SciSciGPT-SciSciNet huggingface dataset:
Role of isotopes and tracers in scaling trace gas fluxes

Publisher Summary This chapter reviews some recent advances in the use of isotopes to infer the global and regional balance of sources and sinks for four trace gases—CO2, CH4, CO, and N2O. These serve as examples of both the power of using isotopes to constrain trace gas budgets and the complications that affect their interpretation. Isotopes are powerful tools for constraining the global budgets of trace gases. Isotopes of an element undergo mass-dependent fractionation during physical, chemical, or biological transformation. The isotopic signature of gases measured in the atmosphere reflects the overall balance of surface sources and sinks and the modifications that occur during atmospheric chemical reactions. The use of isotopes and tracers to determine the importance of microbial and physical transport processes at the plot scale influences the isotopic signature of a specific trace gas source. The process-level understanding of how the environmental conditions (inundation, temperature, and plant composition) determine the isotopic signature of the emitted trace is the key to scaling from the plot (at which measurements are made) to larger scales.
Exploring the relationship between spatial and semantic attention: Two limited capacity systems or one?

Attention is associated with benefit and cost due to competition for limited capacity resources involved in access for awareness. Spatial cues guide spatial attention producing benefit for attended stimuli and cost for unattended stimuli. Semantic relatedness shows a similar pattern: primes produce benefit for related and cost for unrelated stimuli, suggesting they work through semantic attention. An unanswered question is how semantic and spatial attention interact: Does the benefit and cost for related stimuli occur because they attract spatial attention? Three accounts of the relationship between semantic and spatial attention were examined: Semantic attention a) works through spatial attention, b) delays disengagement of spatial attention, and c) is independent of spatial attention. In Experiments 1 to 3, participants performed a visual search task for a prime target in a word display and/or a probe discrimination task on a probe target. Experiments 1a and 1b showed that the word and probe tasks were suitable for examining semantic and spatial attention, respectively. Experiments 2a and 2b showed that in the absence of explicit influences on spatial attention, related distractors led to higher word search task accuracy on target present and lower accuracy on target absent trials. Importantly, related distractors did not attract spatial attention as measured by probe task performance, although they did slow responses on target absent trials. Experiment 3 showed that related distractors also do not attract spatial attention when an abrupt onset spatial cue is presented. Instead, spatial attention was slower to disengage from related versus unrelated distractors on target absent trials. Experiments 4 and 5 examined spatial and semantic attention using the temporal order judgment paradigm in which participants judged which of two stimuli occurred first (or second). Related words and abrupt onset spatial cues had different effects on performance: Relatedness did not influence
The Structure of a Glycopeptide from Human Orosomucoid (α1-Acid Glycoprotein)

Abstract Four glycopeptides were isolated from desialized orosomucoid following digestion with Pronase and chromatography on sulfoethyl cellulose. The structure of the major glycopeptide was studied with sequential hydrolysis with β-galactosidase, β-acetylglucosaminidase, and α-mannosidase, as well as by oxidation with periodate. Evidence for a glycosylamine type linkage between aspartic acid and acetylglucosamine was provided by isolation of 2-acetamido-1-β-(l-β-aspartamido)-1,2-dideoxy-d-glucose (β-aspartyl acetylglucosaminylamine). The major glycopeptide contained 4 moles of galactose, 3 of mannose, 6 of acetylglucosamine, and 1 each of aspartic acid and threonine. The molecular weight of the glycopeptide was 2540 by vapor pressure osmometry and 2840 as measured by forming the trinitrophenyl derivative. Four moles of galactose followed by 4 moles of acetylglucosamine were released per mole of glycopeptide when it was treated sequentially with highly purified β-galactosidase from Phaseolus vulgaris and β-acetylglucosaminidase from bovine liver. This treatment resulted in the exposure of an inner core containing 3 moles of mannose and 2 of acetylglucosamine per mole of aspartic acid. Two moles of mannose and 1 mole of acetylglucosamine were split from the inner core of the oligosaccharide with a crude α-mannosidase preparation from ivory nut, with or without added purified α-acetylglucosaminidase from bovine liver. The intact glycopeptide and its "inner core" were oxidized with sodium periodate. The results from the oxidation and enzymatic studies revealed that the acetylglucosamine linked to asparagine served as a branch point to 2 mannose residues. The likely structure of the glycopeptide is presented.
Making a difference with attention to content, technology, and scale: a session honoring the memory of Jim Kaput

The theme of this year's ICLS, "making a difference," resonates with the life-work of our dear colleague, Jim Kaput, who unexpectedly passed away in summer 2005. Kaput's approach to making a difference was grounded in the Learning Sciences and distinctively attended to the nature of mathematical content, the role of technology, and the problematic of scale. In this symposium, we honor his memory by discussing the current projects of three investigators who continue to drive Kaput's vision forward. These projects address: (1) "foundations for the future" based in a deep reconceptualization of mathematical content (2) technology as representational and connectivity infrastructure that democratizes access to mathematics worth knowing and (3) scale as a challenging problematic essential to "making a difference."
High-Volume, Low-Cost Precursors for Carbon Fiber Production

Carbon fiber composite use in automobiles and light trucks could dramatically reduce energy use and engineout emissions. However, worldwide capacity of 28,000 tonnes per year of carbon fiber from polyacrylonitrile (PAN) and petroleum pitch could support limited automotive use. Production of high-volume, industrialgrade fiber from renewable and recycled polymers (lignin, recycled plastics, regenerated cellulosics) could meet automotive demand. Profiles of material volumes, carbon content, and melting points indicate several attractive candidates for production melt-spun carbon fiber feedstocks. Effects on the carbon fiber production cycle and its integration into automotive production are discussed.
Potential Irreversibilities in Range Management Over Time and Under Uncertainty

A fundamental objective of rangeland managers all over the world is to take measures to ensure that the rangeland being managed stays away from irreversible states in which it provides little or no consumptive and non-consumptive services to humans. Nevertheless, despite a manager's best attempts, the rangeland under study may still hit an irreversible state. Accordingly, given a particular management regime, it is useful to know the length of time taken to hit an irreversible state. In this paper, we conduct a theoretical analysis of this hitherto unstudied question. We first provide a probabilistic description of two range management regimes. Next, we calculate the mean time until an irreversible state is hit for both these regimes. Finally, we provide a numerical example to demonstrate the working of our model and then we discuss the ramifications of our findings for rangeland management in general.
Crack Growth Behavior of Candidate Waste Container Materials in Simulated Underground Water

Fracture-mechanics crack growth tests were conducted on 25.4-mm-thick compact tension specimens of Types 304L and 316L Stainless steel and Incoloy 825 at 93{degrees}C and 1 atmosphere of pressure in simulated J-13 well water, which is representative of the groundwater at the Yucca Mountain site in Nevada that is proposed for a high-level nuclear waste repository. Crack growth rates were measured under various load conditions: load ratios of 0.2--1.0, frequencies of 2 {times} 10{sup {minus}4}{minus}1 Hz, rise times of 1--5000 s, and peak stress intensities of 25--40 MPa{center_dot}m{sup {1/2}}. The measured crack growthrates are bounded by the predicted rates from the current ASME Section 11 correlation for fatigue crack growth rates of austenitic stainless steel in air. Environmentally accelerated crack growth was not evident in any of the three materials under the test conditions investigated.
Sepharose-bound trypsin and activated sepharose-bound trypsinogen. Studies with small and large substrates.

Abstract Several enzymic and physical properties of Sepharose-bound trypsin and activated Sepharose-bound trypsinogen have been compared to those of the soluble enzyme. Sepharose-bound trypsinogen could be activated to the same extent as soluble trypsinogen; the release of the activation peptide and formation of the active site occurred as expected in the presence of catalytic amounts of trypsin. With synthetic substrates, the relative activity and pH dependence of both immobilized trypsin preparations were essentially identical and nearly the same as the soluble enzyme. Sepharose-trypsin also formed an inactive complex with soybean trypsin inhibitor, with 85% of the active sites participating. In contrast, the activity of Sepharose-trypsin with chymotrypsinogen and with trypsinogen as substrates was only 40% that of soluble trypsin. There is evidence for some catalytic heterogeneity of active sites of bound trypsin; probably those sites buried within the gel have a limited catalytic efficiency with macromolecular substrates. The immobilized enzyme is more stable than the soluble enzyme at elevated temperatures and to concentrated urea, and denaturation by urea at pH 8 is fully reversible since the loss of molecules by autolysis is eliminated.
Misclassifying the Insurance Policy: The Unforced Errors of Unilateral Contract Characterization

Insurance policies are traditionally classified as unilateral or “reverse-unilateral” contracts, a characterization we find largely incorrect, with problematic consequences for adjudication of insurance coverage disputes. In addition to the general difficulties attending the unilateral classification, the concept as applied to insurance policies is not only unhelpful but incorrect. Insurance policies are more accurately viewed as bilateral contracts. In addition, the unilateral characterization of insurance policies introduces error and inconsistency into the litigation of insurance controversies. In particular, the unilateral view tends toward excessive formalism and focus on so-called “conditions” precedent to coverage, eschewing material breach analysis and encouraging needless forfeitures as well as unwisely removing the concept of anticipatory repudiation and corresponding remedy from insurance law. Categorizing insurance policies as unilateral fails to appreciate the ongoing, iterative nature of insurance policies and the insurer-policyholder relationship. Recognizing the bilateral nature of insurance policies holds substantial potential for improving insurance coverage adjudication.
Optimal series capacitor compensation of high voltage transmission lines

The technical and economic evaluation of a long lossy transmission line compensated with series capacitors is discussed. The influence of capacitor size and location on the maximum power at the receiving-end, maximum power transfer efficiency and steady-state voltage stability (voltage-collapse) are set forth. It is shown that a certain range of capacitor values and locations are economically justifiable and that for different power factor loads the problem of voltage-collapse is reduced. The size and location of the series capacitor banks do not have much impart on the maximum power transfer efficiency but are of importance in the determination of the load power factor at which this occurs. >
Consistent estimation of cardiac motions by 4D image registration

A 4D image registration method is proposed for consistent estimation of cardiac motion from MR image sequences. Under this 4D registration framework, all 3D cardiac images taken at different time-points are registered simultaneously, and motion estimated is enforced to be spatiotemporally smooth, thereby overcoming potential limitations of some methods that typically estimate cardiac deformation sequentially from one frame to another, instead of treating the entire set of images as a 4D volume. To facilitate our image matching process, an attribute vector is designed for each point in the image to include intensity, boundary and geometric moment invariants (GMIs). Hierarchical registration of two image sequences is achieved by using the most distinctive points for initial registration of two sequences and gradually adding less-distinctive points for refinement of registration. Experimental results on real data demonstrate good performance of the proposed method in registering cardiac images and estimating motions from cardiac image sequences.
Molecular cloning and cellular localization of a BiP homologue in Trypanosoma brucei. Divergent ER retention signals in a lower eukaryote

Using the polymerase chain reaction with degenerate primers, three new members of the hsp70 gene family of Trypanosoma brucei have been identified. A genomic clone of one of these, gA, has been fully sequenced and the corresponding gene product has been characterized using antibody to recombinant gA fusion protein. gA is the trypanosomal homologue of BiP, an endoplasmic reticulum resident hsp70 gene family member, based on four lines of evidence: (1) gA protein has 64% deduced amino acid identity with rat BiP; (2) the deduced amino acid sequence has a putative secretory signal peptide; (3) the gA gene product is a soluble luminal resident of a trypanosomal microsome fraction; (4) the gA polypeptide does not cofractionate with mitochondrial markers. Trypanosomes are the most primitive eukaryote yet in which BiP has been identified. The gA polypeptide has been used as a specific marker for the direct visualization of endoplasmic reticulum in trypanosomes by both indirect immunofluorescence and cryoimmuno electron microscopy. The endoplasmic reticulum is seen as a tubular network that extends throughout the cell excluding the flagellum. The C-terminal tetrapeptide of gA is MDDL, which, together with the C-terminal tetrapeptide (KQDL) of a trypanosome protein disulfide isomerase homologue (Hsu et al. (1989) Biochemistry 28, 6440-6446), indicates that endoplasmic reticulum retrieval signals in trypanosomes may be as divergent and heterogeneous as any seen in the other eukaryotes yet studied.
Multilevel Exploration of Factors Contributing to the Overrepresentation of Black Students in Office Disciplinary Referrals

Although there is increasing awareness of the overrepresentation of ethic minority students -particularly Black students- in disciplinary actions, the extant research has rarely empirically examined potential factors that may contribute to these disparities. The current study used a multilevel modeling approach to examine factors at the child (e.g., teacher-rated disruptive behavior problems) and classroom or teacher levels (e.g., teacher ethnicity, level of disruptive behavior in classroom) that may contribute to the overrepresentation of minority students in office disciplinary referrals (ODRs). Data come from 6,988 children in 381 classrooms at 21 elementary schools. The analyses indicated that even after controlling for the student's level of teacher-rated behavior problems, teacher ethnicity, and other classroom factors, Black students were significantly more likely than White students to receive ODRs. Results also suggested that ethnic match between students and their teachers did not reduce the risk for referrals among Black students.
COBE Spectra Apheresis System: designs, protocols and results.

The COBE Spectra® System will perform all types of apheresis procedures. One of its main procedures is to collect single donor platelets. Because of the unique abilities of this device, the
PCR primers for identification of Sirococcus conigenus and S. tsugae, and detection of S. conigenus from symptomatic and asymptomatic red pine shoots

Summary Regions of diversity in the internal transcribed spacer (ITS) sequences of Sirococcus species were exploited to design primer pairs used in a PCR-based method for the identification of the conifer shoot blight pathogen Sirococcus conigenus and the closely related fungus Sirococcus tsugae. The specificity of each primer pair for the respective fungus, detection limits and utility for detection from host material were confirmed. The S. conigenus primers were then used to detect this pathogen in tissues of symptomatic or apparently healthy red pine shoots collected at six locations in Wisconsin and Michigan and results compared with those obtained using a cultural assay. For needles, bark and wood of symptomatic shoots, the mean frequencies of detection of S. conigenus using the PCR-based methods were consistent (≥7.5 out of 10) and always greater than for the cultural assay. Detection from symptomatic shoots using the cultural assay was more frequent from needles than from bark or wood. Both the PCR-based method and the cultural assay detected S. conigenus in similar frequencies from asymptomatic shoots, although less frequently than from symptomatic shoots. The efficiency of the PCR-based method and its utility for direct testing of host material should make it particularly useful in areas where multiple shoot blight pathogens are found.
Various estimators of conditional probabilities of death in follow-up studies: Summary of results

In medical follow-up studies the data on mortality experience of a specified population at risk are usually ‘incomplete’ in the sense that the study terminates before all the patients die, so that their final survival duration is unknown. The data are often grouped in fixed intervals, [ti, ti + 1), say, including individuals who die, are withdrawn alive or survive the full interval. An important problem in the statistical analysis is to estimate qi—the conditional probability that an individual alive at the beginning of the interval, will die within the interval. Various estimators have been proposed in the literature. The present paper gives a summary of the results on six possible estimators of qi and discusses briefly assumptions and methods of derivation. It is hoped that Table 1 will be of use to medical investigators in the analysis of survivorship from chronic diseases. An example on mortality of 5982 women diagnosed with cancer of the cervix uteri is used to illustrate some of the computing techniques and to compare the various estimators.
Killing of Mycobacterium tuberculosis by Neutrophils: A Nonoxidative Process

To determine the role of oxygen radicals in the killing of Mycobacterium tuberculosis by neutrophils, the effects of free-radical inhibitors and enzymes, catalase, superoxide dismutase, taurine, deferoxamine, and histidine were evaluated. Changes in the viability of M. tuberculosis were determined by agar plate colony counts and a radiometric assay. No impairment in killing was seen with any of the inhibitors or enzymes. Patients with chronic granulomatous disease (CGD) have a defect in the NADPH oxidase pathway, causing their neutrophils to be unable to generate oxygen radicals. If these radicals are involved in killing, then CGD neutrophils should be less effective killers of M. tuberculosis than normal neutrophils. There was no evidence by either measure of M. tuberculosis viability that CGD neutrophils were less bactericidal than normal neutrophils. Killing by normal neutrophils was also effective in the absence of serum. These results lead to the conclusion that the mechanism by which M. tuberculosis is killed by neutrophils is independent of the oxygen metabolic burst.
The rate structure of the natural gas pipeline industry

Many economists have urged regulatory commissions to pay closer attention to the rate structures of public utility companies. Tele-communications, rail transportation, and electric power are all said to be practical areas of rate structure experimentation. However, the rate structure of the natural gas pipeline industry, a regulated sector of the economy, has received limited comment. This is particularly disappointing since natural gas is significant in the nation's pattern of energy consumption. The purpose of this article is to identify the current rate structures and practices of the natural gas pipeline industry in the United States. In addition, the rate burden for certain buyers of natural gas service should become more apparent. To determine the current rate structures and practices, the roles of eight natural gas pipeline companies, 1 which together serve most regions of the United States, are studied. Only those tariffs are examined where service is not subject to any interruptability up to the ...
RECENT ADVANCES IN CYTOLOGY

The acceptance of an invitation to outline for you in a few minutes the recent advances in cytology places me between two hazards characteristic of such a situation. On one hand is the danger of making statements so general and obvious that they would be devoid of new meaning and therefore wasteful of your time, and on the other is the risk of presenting an arid recital of bare facts equally unkind to your patience. The difficulty increases when one inclines toward a definition of cytology broad enough to include any work in which the cell is more or less directly studied with scientific method, no matter what the special avenue of approach; and when one regards as advances not simply the establishment of new facts or the attainment of certain temporary goals, but also the consideration of old facts from new points of view, the recognition of errors, the invention or adaptation of new methods, the formulation of new and useful provisional hypotheses, the correlation of neighboring fields of research, and the confident entry upon new paths of endeavor. Neither in generalities nor in particulars alone can recent cytological progress be represented. I shall therefore follow a somewhat ill-defined middle course by limiting my account to a very few of the developments which cytologists have recently witnessed in their field, with some indication of their reasons for considering them of sufficient significance to be brought before you on this occasion. Protoplasm. I can think of no problem of more fundamental importance to cytology, and to all biology, than that of the nature of the physical basis of life. After the masterly addresses of Professor Harper at Pittsburgh and Professor Wilson at Boston I feel that comparatively little remains for me to say on this subject, but it may not be superfluous to emphasize anew the impetus which the conception of protoplasm as a colloidal system has given to all types of cell study. In the first place, it has encouraged a more thoroughgoing investigation of the cell in the living state. This has involved the devising of ingenious methods by which we have already been able to remove many misconceptions originally growing out of the too-exclusive use of fixed material. Again, by furnishing us with a new and suggestive theoretical basis of interpretation for the data obtained from morphological and physiological cell studies, it has aided us in finding plausible partial explanations for a variety of puzzling phenomena, among which we may mention cytokinesis,
Functional imaging of working memory and peripheral endothelial function in middle-aged adults.

Abstract The current study examined the relationship between a prognostic indicator of vascular health, flow-mediated dilation (FMD), and working memory-related brain activation in healthy middle-aged adults. Forty-two participants underwent functional magnetic resonance imaging while completing a 2-Back working memory task. Brachial artery endothelial-dependent flow-mediated dilation (FMD) was assessed using B-mode ultrasound. The relationship between FMD and task-related brain activation in a priori regions of interest was modeled using hierarchical linear regression. Brachial FMD, was significantly related to reduced working memory-related activation in the right superior parietal lobule ( β = 0.338, p = 0.027), independent of age, sex, systolic blood pressure, and full scale IQ ( F (5, 36) = 2.66, p = 0.038). These data provide preliminary support for the association between a preclinical marker of endothelial dysfunction and cerebral hemodynamic alterations in healthy middle-aged adults. Considering the modifiable nature of endothelial function, additional investigations on the prognostic significance of FMD on future cognitive impairment are warranted.
Spectrum-Aware Beaconless Geographical Routing Protocol for Mobile Cognitive Radio Networks

A key challenge in cognitive radio networks (CRNs) is how to adaptively and efficiently select a route and assign resources along that route according to the surrounding environment. In this work, we propose a distributed routing protocol for mobile CRNs, in which path selection and resource allocation (e.g., spectrum, transmission power, and transmission rate) are determined by receivers. Because this process is done on perpacket and per- hop basis, the proposed protocol can efficiently adapt to spectrum dynamics and node mobility. In addition, spectrum efficiency is increased through dynamic spectrum allocation and transmission power control. Simulation results show that delivery ratio and throughput are dramatically improved with our routing protocol.
Reproductive care for adolescents with disability: Where should they get it?

Access to reproductive health care is essential to all adolescents. It is important to help them understand their pubertal changes and to address their concerns as well as to detect and treat any abnormalities. It is also crucial for providing important prevention strategies against sexually transmitted infections teen pregnancy cervical and breast cancer and sexual assault. Although some adolescents in the United States do not have access to reproductive health care or are unaware of where to get it it is even worse for adolescents with physical and/or mental disabilities. This is because of numerous factors including poor training of health care professionals time restraints and poor reimbursement for services and the myths and misinformation regarding sexuality of adolescents with disability. (excerpt)
A Cross-Layer Analytical Model to Estimate the Capacity of a WiMAX Network

Specialized physical and medium access control layer operations of WiMAX introduce a challenging problem to formulate a precise cross-layer analytical model for its capacity estimation. Although the cross-layer formulation is yet to be attempted in the literature, it can effectively serve as a fast and cost-effective tool to facilitate future deployment planning, efficient network maintenance, etc., and thus can expedite to cope up with the recent blast in WiMAX deployment. Therefore, we propose a novel formulation of cross-layer analytical model for WiMAX capacity estimation in this paper. Our formulation addresses intricate interrelationships between different layers in a protocol stack. Besides, the formulation separately addresses both reliable and unreliable transport layer transmissions. We verify our formulated model using ns-2 simulation, which reveals that the model can estimate the capacity of a WiMAX network with as low as 1% average error having a standard deviation of only 1%. Consequently, we find that the proposed model can achieve up to a 97% decrease in the average error compared to other available analytical models in the literature. Finally, we present different applications of the proposed model by utilizing it in network planning and protocol overhead analysis.
The use of stilbestrol inhibited males as test animals for gonadotrophic hormones.

That estrogenic substances have an inhibiting effect on the gonadotrophic activity of the pituitary of mammals has been amply demonstrated in endocrine literature. The use of stilbestrol as a “fattening” hormone in chickens has shown that a pronounced modification of the rate of function of the pituitary may be accomplished. Implants of as little as 15 mgs. of stilbestrol into males will cause complete regression of the testes and subsequently the comb, while larger doses will lead to a cessation of growth and will induce conditions in some instances resembling surgical hypophysectomy (Nalbandov & Card, 1943). These observations led to the idea that the physiological inhibition of the pituitary by estrogen may be used in the laboratory in place of surgical hypophysectomy. The advantage of the former lies in the fact that it is possible to make implants into large numbers of animals in a very short time,
Finding the right data for software cost modeling

Good software cost models can significantly help software project managers. With good models, project stakeholders can make informed decisions about how to manage resources, how to control and plan the project, or how to deliver the project on time, on schedule, and on budget. Real-world data sets, such as those coming from software engineering projects, often contain noisy, irrelevant, or redundant variables. We propose that cost modelers should perform data-pruning experiments after data collection and before model building. Such pruning experiments are simple and fast.
Mucolytic effects of Helicobacter pylori.

The mechanisms associated with colonization of human gastroduodenal mucosa by Helicobacter pylori remain unclear. To colonize gastric-type epithelium H. pylori must enter the gastric lumen, resist damage by all bactericidal factors operating within the acidic gastric milieu, penetrate the mucus gel despite highly viscous and hydrophobic properties of the mucus layer, and, finally, secure optimal conditions for its further multiplication. Since the H. pylori microorganism has been seen freely spread throughout the entire mucus layer thickness as well as in intimate contact with surface epithelium, the interrelationship between this spiral microorganism and the mucus seems to be of paramount importance. H. pylori has been shown to affect adversely the chemical and physical properties of the mucus layer. Therefore, the mucus layer compromised by the presence of this microorganism may become an easy target for acid and peptic damage, which ultimately leads to mucosal pathology, inflammation and/or peptic ulce...
Deformed frogs and environmental retinoids

Since the early 1990s, a substantial number of deformed frogs have been observed in North America, particularly in the upper Midwest and Canada. Attempts to understand the etiology of the deformed frog problem have met with limited success to date with nearly as many proposed explanations as research groups working on the problem. Models for the mechanism underlying the development of deformed frogs include parasite/predation, ultra- violet radiation, and chemical exposure. Each model has its strengths and weaknesses. Despite contentious debate among researchers, there is an overall consensus that the in- creasing prevalence of deformed frogs is the result of a water-borne contaminant that has re- cently appeared, or reached a critical concentration. Our detailed analysis of malformed frogs collected in Minnesota ponds and lakes suggested that limb patterning was being modified by the disruption of a retinoid-sensitive developmental signaling pathway. Accordingly, we focused in the identification and characterization of bioactive retinoids from lake water and showed that retinoid treatment of frog embryos at sensitive times of development could re- capitulate the full spectrum of limb abnormalities observed in field specimens in the labora- tory. These data have led to the conclusion that inappropriate modulation of retinoid signal- ing by environmental contaminants is the mechanism underlying the increased incidence of frog malformations.
Elucidation of the evolution and taxonomy of cultivated potatoes with electrophoresis : I. Groups tuberosum, andigena, phureja and stenotomum.

A recently developed polyacrylamide gel electrophoresis technique for tuber proteins is used to help elucidate the evolution and taxonomy of some cultivated potatoes. The results substantiate the theory that Group Tuberosum evolved from Group Andigena, that Group Andigena evolved from a cultivated diploid × wild diploid hybrid, and that Group Phureja evolved from Group Stenotomum. Furthermore, the results suggest these groups are closely enough related to merit classification within a single species.
Pharmacological protection of reoxygenation damage to in vitro brain slice tissue.

Pharmacological protection of central neural function against damage by hypoxia and reoxygenation was studied electrophysiologically and biochemically in hippocampal brain slices. Hypoxia causes a loss of both orthodromically and antidromically evoked potentials in CA1 pyramidal cell neurons. Damage due to hypoxia lasting more than 10 min cannot be restored by reoxygenation. Following pretreatment with methylprednisolone (10−5 M), indomethacin (10−5 M) or allopurinol (10−5 M), reoxygenation after 10 min of hypoxia resulted in complete recovery of the evoked activity. Na+,K+-ATPase activity was not reduced by 10 min of hypoxia, but was reduced by 50% during the first 10 min of subsequent reoxygenation. Allopurinol (10−5 M) and indomethacin (10−5 M) protected against loss of this enzyme activity. The protective action by these drugs of both electrophysiological and biochemical aspects of neural function is consistent with the hypothesis that secondary ischemic damage is caused by the formation of oxygen-derived free radicals during reperfusion.
Developmentally Regulated Male-Specific Transfactor(s) Enable in Vitro Transcription of a Cloned α2U-Globulin Gene

Selected members of the rat α2u-globulin gene family are expressed in several tissues, manifesting characteristic developmental and endocrine transcriptional control. Studies are now underway to identify the responsible cis sequences and transacting factors. We recently reported that the cloned rat α2u-globulin 207 gene manifests tissue-specific androgen-dependent expression; it is expressed in livers of male, but not female, transgenic mice. In the present study a portion of this gene (−639 to +1395) is used as an in vitro template in the presence of nuclear extracts derived from hepatic nuclei of prepubescent and mature male and female rats, α-Amanitin-sensitive in vitro transcription of the α2u 207 gene by extracts derived from mature male rats is highly active and is at least 13 times as rapid as that with preparations from mature female or immature animals. In contrast, the rate of transcription of a control template, the adenoviral late promoter, is the same with all of these nuclear extracts. S1 nu...
Transplant Outcomes in Mucopolysaccharidoses

The mucopolysaccharidoses (MPSs) are inherited metabolic disorders (IMDs) caused by single-gene defects leading to progressive cellular accumulation of glycosaminoglycans (GAGs) and damage to multiple organs, including the central nervous, musculoskeletal, cardiorespiratory, and other systems. Hurler syndrome (MPS IH), the most severe form, is the prototypical model. Enzyme replacement therapy (ERT), available for MPS I, II, and VI, is beneficial in some patients. However, ERT does not improve neurocognitive function because of its inability to cross the blood-brain barrier. In contrast, allogeneic hematopoietic stem cell transplantation (HSCT) allows donor-derived, enzyme-producing cells to migrate to the brain and other organs to provide permanent enzyme therapy and thus help somatic organs, improve neurocognitive function and quality of life, and prolong survival, particularly when performed early in the course of the disease. Bone marrow has been the graft source in the past. However, in the last 5 years many patients have been treated with unrelated donor (URD) umbilical cord blood transplant (UCBT), allowing rapid and increased access to transplantation with favorable outcomes. This review describes published and our institutional clinical experiences, discusses the current status of the field, and provides therapy guidelines for patients with MPS.
Partial characterization of K+-induced increase in [Ca2+]cyt and GnRH release in GT1-7 neurons

Secretion of pituitary gonadotropins is regulated centrally by the hypothalamic decapeptide gonadotropin releasing hormone (GnRH). Using the immortalized hypothalamic GT1-7 neuron, we characterized pharmacologically the dynamics of cytosolic Ca2+ and GnRH release in response to K+-induced depolarization of GT1-7 neurons. Our results showed that K+ concentrations from 7.5 to 60 mM increased [Ca2+]cyt in a concentration-dependent manner. Resting [Ca2+]cyt in GT1 -7 cells was determined to be 69.7 +/- 4.0 nM (mean +/- S.E.M.; n = 69). K+-induced increases in [Ca2+]cyt ranged from 58.2 nM at 7.5 mM [K+] to 347 nM at 60 mM [K+]. K+-induced GnRH release ranged from about 10 pg/ml at 7.5 mM [K+] to about 60 pg/ml at 45 mM [K+]. K+-induced increases in (Ca2+]cyt and GnRH release were enhanced by 1 microM BayK 8644, an L-type Ca2+ channel agonist. The BayK enhancement was completely inhibited by 1 microM nimodipine, an L-type Ca2+ channel antagonist. Nimodipine (1 microM) alone partially inhibited K+-induced increases in [Ca2+]cyt and GnRH release. Conotoxin (1 microM) alone had no effect on K+-induced GnRH release or [Ca2+]cyt, but the combination of conotoxin (1 microM) and nimodipine (1 microM) inhibited K+-induced increase in [Ca2+]cyt significantly more (p < 0.02) than nimodipine alone, suggesting that N-type Ca2+ channels exist in GT1-7 neurons and may be part of the response to K+. The response of [Ca2+]cyt to K+ was linear with increasing [K+] whereas the response of GnRH release to increasing [K+] appeared to be saturable. K+-induced increase in [Ca2+]cyt and GnRH release required extracellular [Ca2+]. These experiments suggest that voltage dependent N- and L-type Ca2+ channels are present in immortalized GT1-7 neurons and that GnRH release is, at least in part, dependent on these channels for release of GnRH.
Barrier electrophoresis: A new electrophoretic technique☆☆☆

Abstract Barrier electrophoresis, a preparative technique that combines the resolving capacity of zone electrophoresis in gels with continuous flow, is described. Several applications of barrier electrophoresis to the purification of macromolecules are presented.
Developing Map Symbol Standards through an Iterative Collaboration Process

Geographic information is commonly disseminated and consumed via visual representations of features and their environmental context on maps. Map design inherently involves generalizing reality, and one method by which mapmakers do so is through the use of symbols to represent features. Here we focus on the challenges associated with supporting mapmakers who need to work together to reach consensus on standardizing their map symbols. On the basis of a needs assessment study with mapmakers at the US Department of Homeland Security, we designed a new, mixed-method symbol standardization process that takes place through a web-based, asynchronous platform. A study to test this new standardization process with mapmakers at DHS revealed that our process allowed participants to identify many issues related to symbol design, meaning, and categorization. The approach elicited sustained, iterative engagement and critical thinking from participants, and results from a poststudy survey indicate that participants found...
Design, simulation, and fabrication of a novel integrated microaccelerometer utilizing a post-CMOS fabrication technique

Design, simulation, and fabrication of an integrated microaccelerometer, which is one of several applications of a novel device called Laterally Movable Gate FET (LMGFET) are presented. A LIGA-like post-IC fabrication method compatible with monolithic integration of electronic circuits in standard CMOS technology is utilized to fabricate the accelerometers. External acceleration results in motion of LMGFET differential gates, which cause the drain currents in the FETs to change linearly with position and hence motion. Two types of designs are utilized as restraining springs, which are rigidly anchored to the substrate. The gate motion is first simulated by FEM to analyze its mechanical response. The simulation predicts resonance frequencies of the structures to be 6.32 kHz and 4.66 kHz and gate mechanical motion sensitivity values of 6.23 and 11.47 nm/unit acceleration in g. The op-amp is designed, simulated using PSPICE and fabricated using a 1.5 μm standard CMOS process to amplify the sensor output signal. The simulated values for sensitivity of the two accelerometers are 0.23 mV/g and 0.42 mV/g for the folded beam and the serpentine structure, respectively for an amplifier gain of 45.4 (33.14 dB). The LMGFET microaccelerometers show promise for extremely high dynamic linear operating range.
Noninvasive Metabolic Analysis of Preserved Rabbit Cornea

• With the method of corneal redox fluorometry, the autofluorescence of reduced pyridine nucleotides (PN) and oxidized flavoproteins (Fp) in rabbit corneal endothelium was measured as a function of storage time in McCarey-Kaufman (MK) medium and K-Sol medium. Measurements were started immediately after preparation of the corneal button, and the corneas were followed up for up to three weeks of storage. In both media, the PN/Ep ratio of the endothelium initially increased slightly in the first or second day and then began to decrease toward a level lower than baseline. This initial increase is possibly a result of an adaptive mechanism. The PN/Fp ratio maintained itself in the range of baseline values up to one week in MK medium but not in K-Sol medium. With scanning electron microscopy, the surface of the membrane and cell border were maintained for a three-week preservation period, and no apparent differences were found between the corneas stored in the two media. With transmission electron microscopy, the intracellular organelles appeared almost normal through one week of preservation in corneas stored in either media. During weeks 2 and 3, however, intracellular edema with increased endothelial thickness became prominent in the corneas stored in both media. Although no visual difference in the morphological features of the endothelium was apparent between corneas stored in either medium, computer-assisted morphometric analysis showed a statistically significant increase in the coefficient of variation of mean cell area for the corneas preserved in K-Sol medium but not for those preserved in MK medium.
Transcriptional and Biochemical Effects of Cadmium and Manganese on the Defense System of Octopus vulgaris Paralarvae

Due to anthropogenic activities the relative concentrations of cadmium and manganese have increased in the marine environment. Cephalopods are able to accumulate such metals and, as inhabitant of coastal waters, Octopus vulgaris is continuously exposed to anthropogenic activities. Since no study is available on the effects of heavy metals at molecular level in developing octopuses, herein we exposed 1-day-old paralarvae for 24 h to 10, 100, and 1000 μg/L of CdCl2 or MnCl2. Cd exerted a concentration-dependent inhibition of survival and a reduction in growth rate was shown while Mn exposure did not affect the survival rate even at the highest concentrations. Gene expression profiles of hsp70, sod, cat, and gst genes were analyzed by quantitative real-time PCR and defined patterns of transcription were observed. Moreover posttranscriptional analyses were also performed suggesting the impairment of metabolic functions, under strong oxidative conditions (as occurred in paralarvae exposed to Cd) or the complete detoxification events (as occurred in paralarvae exposed to Mn).
Metaphorical images of schooling: beliefs about teaching and learning among prospective teachers from the United States displaying different motivational profiles

This study focused on investigating the types of schooling beliefs (teaching and learning) expressed through metaphorical images by prospective teachers (PTs) from the United States. Participants (N = 215) rated 10 schooling metaphors illustrating the student–school–teacher relationships (i.e. Passenger–Bus–Driver; Student is a passenger, School is a bus and Teacher is a driver). Two main factors, a student-centred and a teacher-centred approach described the key schooling beliefs of PTs. Additionally, differences in PTs’ schooling beliefs across typologies/clusters of PTs were found. Further, qualitative data from interviews illustrated how each cluster specifically expressed their instructional views.
End‐User Searching of Online Databases: A Selective Annotated Bibliography

Literature related to end‐user searching of online databases is cited and annotated. Questions such as the role of the librarian/intermediary, the cost effectiveness of end‐user searching, and the training of end‐user searchers are addressed by the cited literature. Articles and conference papers from 1981–1984 are covered.
A measurement study of resource utilization in internet mobile streaming

The pervasive usage of mobile devices and wireless networking support have enabled more and more Internet stream- ing services to all kinds of heterogeneous mobile devices. However, Internet mobile streaming services are challenged by the inherently limited on-device resources, device heterogeneity, and the bulk amount of streaming data. In this paper, focusing on resource utilization and streaming quality on mobile devices, we investigate 10 deployed Internet mobile streaming services that employ client-server, client-proxy-server, and P2P architectures from a client's perspective. We find that (1) existing Internet mobile streaming services mainly use the client-server architecture and commonly adopt burst traffic delivery that can save battery power consumption on mobile devices; (2) to deal with device heterogeneity, some streaming services have already utilized intermediate nodes (often the user's home computer) for online transcoding with a client-proxy-server architecture, but currently they lack power-friendly design for mobile devices; (3) a mobile device in P2P streaming consumes significantly more battery power mainly due to the inevitable P2P control traffic and uploading traffic to other peers. These findings provide us new insights to further optimize Internet mobile streaming in the future.
The Morphology of Poly(3,4-Ethylenedioxythiophene)

Poly(3,4-ethylene dioxythiophene) (PEDOT) is a chemically stable, conjugated polymer that is of considerable interest for a variety of applications including coatings for interfacing electronic biomedical devices with living tissue. Here, we describe recent work from our laboratory and elsewhere to investigate the morphology of PEDOT in the solid state. We discuss the importance of oxidative chemical and electrochemical polymerization, as well as the critical role of the counterion used during synthesis and film deposition. We have obtained information about the morphology of PEDOT from a number of different complimentary techniques including X-ray diffraction, optical microscopy, scanning electron microscopy, transmission high-resolution electron microscopy, and low-voltage electron microscopy. We also discuss results from ultraviolet-visible light spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). PEDOT is a relatively rigid polymer that pa...