cssi/SciSciGPT-SciSciNet huggingface dataset:
Ultraviolet radiation alters the phosphorylation of RNA polymerase II large subunit and accelerates its proteasome-dependent degradation

It has been shown that ultraviolet (UV) radiation induces the ubiquitination of the large subunit of RNA polymerase II (RNAP II-LS) as well as its proteasomal degradation. Studies in mammalian cells have indicated that highly phosphorylated forms of RNAP II-LS are preferentially ubiquitinated, but studies in Saccharomyces cerevisiae have provided evidence that unphosphorylated RNAP II-LS is an equally suitable substrate. In the present study, an antibody (ARNA-3) that recognizes all forms of RNAP II-LS, regardless of the phosphorylation status of its C-terminal domain (CTD), was utilized to evaluate the degradation of total cellular RNAP II-LS in human fibroblasts under basal conditions or after UV-C (10J/m(2)) irradiation. It was found that UV radiation rapidly shifted the phosphorylation profile of RNAP II-LS from a mixture of dephosphorylated and phosphorylated forms to entirely more phosphorylated forms. This shift in phosphorylation status was not blocked by pharmacologic inhibition of either the ERK or p38 pathways, both of which have been implicated in the cellular UV response. In addition to shifting the phosphorylation profile, UV radiation led to net degradation of total RNAP II-LS. UV-induced degradation of RNAP II-LS was also greatly reduced in the presence of the transcriptional and CTD kinase inhibitor DRB. Using a panel of protease inhibitors, it was shown that the bulk of UV-induced degradation is proteasome-dependent. However, the UV-induced loss of hypophosphorylated RNAP II-LS was proteasome-independent. Lastly, UV radiation induced a similar shift to all hyperphosphorylated RNAP II-LS in Cockayne syndrome (CS) cells of complementation groups A or B (CSA or CSB) when compared to appropriate controls. The UV-induced degradation rates of RNAP II-LS were not significantly altered when comparing CSA or CSB to repair competent control cells. The implications for the cellular UV response are discussed.
Further results on willingness to pay for nonmarket goods

Abstract Some implications of substitution relationships between private and public goods for measuring the value of changes in nonmarket goods such as environmental quality are explored. If a market good is (Hicks-) neutral to quality for some price vector, the total value of discrete changes in quality, consisting of both use and nonuse value, can be measured from empirical demand coefficients. A plausible motivation for neutrality is developed in the contexts of specifying incomplete demand systems for weak complements to quality and measuring nonuse value when the consumption of weak complements is (held at) zero. Previous results on bounding marginal willingness to pay for nonmarket goods are also strengthened.
A fuzzy sets modelling approach for ergonomic workload stress analysis

Abstract The Ergonomic Workload Stress Index (EWSI) model was developed to predict the existence and level of the ergonomic workload stress via the concept of the fuzzy sets theory. The linguistic values (e.g., “heavy”, “uncomfortable”, etc.) of the tasks and workplace variables (e.g., physical job demand, postural, environmental stressors, etc.) which have most influential factors on stress were defined. The computerized system was developed to investigate the inappropriate tasks and workplaces and to suggest alternative solutions to problems. The EWSI model was implemented in three industrial environments (i.e., grocery store distribution warehouse, drilling tools manufacturer, and linen and uniform rental service industry) from the epidemiological and physiological viewpoints to validate the model. The following results were obtained from the validation process: (1) a positive relationship between the EWSI value and the severity of injury and illness rate (coefficient of correlation = 0.716, 0.917, and 0.854 for the three different industries); (2) a close linear relationship between the EWSI value and heart rate (coefficient of correlation = 0.845); and (3) a close linear relationship between the EWSI value and blood pressure (coefficient of correlation = 0.804 and 0.775 for the systotic and diastolic blood pressure, respectively).
Overwintering of Microcystis in Lake Mendota

SUMMARY. Microcystis, an important bloom-forming blue-green alga in Lake Mendota, Wisconsin, was found to accumulate at the lake bottom and overwinter there. Microcystis collected from winter sediments were photosynthetically active, showing temperature and light optima similar to summer and autumn populations. Sediments incubated under in situ conditions in the laboratory maintained photosynthetic activity for at least four months. Such a maintenance ability may be part of an overall strategy by Microcystis populations to ensure a suitable inoculum for the following growth season.
Melittin-phospholipid interaction studied by employing the single tryptophan residue as an intrinsic fluorescent probe.

Abstract The rotational correlation time of melittin, obtained from the nanosecond anisotropy of the emission from its single tryptophan residue, has been found to increase considerably in phosphate solution relative to that in aqueous solution, consistent with protein aggregation. The steady-state fluorescence spectra as well as the absorption spectra in phosphate solution exhibit a very good degree of similarity with those of the protein bound to egg phosphatidylcholine (PC) and distearoylphosphatidylcholine (DSPC) bilayer liposomes. The value of the second-order rate constant for dynamic quenching, k q = 1.4·10 9 M −1 · s −1 , by acrylamide in 0.5 M phosphate solution is comparable to those for the protein-phospholipids complexes (1·10 9 and 0.7·10 9 M −1 ·s −1 for egg PC and DSPC, respectively). Similarities are also found in the nanosecond properties. There is a much stronger and quite similar dependence of the fluorescence spectra on time in the nanosecond range and of the fluorescence decay times on the emission wavelength in both cases as compared to the case in aqueous solution. These observations support the notion that melittin binds to the phospholipids in an aggregated form. The results suggest that the reduction in the k q values of bound melittin relative to that in aqueous solution and the blue shift of the fluorescence spectrum (from 352 to 337 nm) are brought about by shielding of the tryptophan residue from the solvent through a combination of protein aggregation and enhancement of its α-helical content (suggested by published CD data). The magnitude of the k q values for bound melittin, however, is still relatively high implying the occurrence of rather frequent encounters between the tryptophan residue and the hydrophilic acrylamide molecules. Thus, the residue is found not to penetrate deep into the phospholipid bilayer.
Channel selection using information content analysis: A case study of CO2 retrieval from near infrared measurements

A major challenge in retrieving CO_2 concentrations from thermal infrared remote sensing comes from the fact that measurements in the 4.3 and 15 μm absorption bands (AIRS or TES) are sensitive to both temperature and CO_2 variations. This complicates the selection of absorption channels with maximum CO_2 concentration information content. In contrast, retrievals using near infrared (NIR) CO_2 absorption bands are relatively insensitive to temperature and are most sensitive to changes of CO_2 near the surface, where the sources and sinks are located. The Orbiting Carbon Observatory (OCO) was built to measure reflected sunlight in three NIR spectral regions (the 0.76 μm O_2 A-band and two CO_2 bands at 1.61 and 2.06 μm). In an effort to significantly increase the speed of accurate CO_2 retrieval algorithms for OCO, we performed an information content analysis to identify the 20 best channels from each CO_2 spectral region to use in OCO retrievals. Retrievals using these 40 channels provide as much as 75% of the total CO_2 information content compared to retrievals using all 1016 channels in each spectral region. The CO_2 retrievals using our selected channels have a precision better than 0.1 ppm. This technique can be applied to the retrieval of other geophysical variables (e.g., temperature or CH_4), or modified for other instruments, such as AIRS or TES.
K -matrix analysis of resonance nuclear reactions

A simple parametrization of nuclear reaction cross sections in terms of resonance parameters is obtained from the expansion of a modified scrK matrix. The latter is defined in such a way that it has no other singularity in the complex energy plane than its poles. When expanded in terms of these poles, it can be used to analyze and parametrize low-energy data on resonance reactions. The pole energies ${\mathit{E}}_{\ensuremath{\lambda}}$ are the resonance energies without shift (except when there is a nearby threshold of a closed neutron channel), and the residues are the products of reduced width amplitudes ${\mathit{g}}_{\mathit{c}\ensuremath{\lambda}}$. These two sets of parameters (${\mathit{E}}_{\ensuremath{\lambda}}$,${\mathit{g}}_{\mathit{c}\ensuremath{\lambda}}$) are independent of the channel radii and no boundary condition constants are involved in their definitions. Also, few-level approximations of the expanded scrK matrix retain the unitarity of the S matrix. These properties add more reliability to the extrapolation of data to lower energies, as often necessary for reactions of astrophysical interest.
A practical synthesis of the modified RNA nucleoside pseudouridine

Abstract An alternative synthesis of the modified RNA nucleoside pseudouridine is reported. This procedure employs coupling of an iodinated pyrimidine and a suitably protected lactone. The resulting hemiacetal is reduced and deprotected to yield pseudouridine.
Current advances in Holt-Oram syndrome

Holt-Oram syndrome is an autosomal-dominant condition characterized by congenital cardiac and forelimb anomalies. It is caused by mutations of the TBX5 gene, a member of the T-box family that encodes a transcription factor. Molecular studies have demonstrated that mutations predicted to create null alleles cause substantial abnormalities in both the limbs and heart, and that missense mutations of TBX5 can produce distinct phenotypes. One class of missense mutations causes significant cardiac malformations but only minor skeletal abnormalities; others might cause extensive upper limb malformations but less significant cardiac abnormalities. Intrafamilial variations of the malformations strongly suggest that genetic background or modifier genes play an important role in the phenotypic expression of HOS. Efforts to understand the intracellular pathway of TBX5 would provide a unique window onto the molecular basis of common congenital heart diseases and limb malformations.
A micromethod for the determination of ceramide.

Abstract An enzymatic micromethod for the determination of ceramide is presented. The enzyme, E. coli diglyceride kinase was used to phosphorylate ceramide, as well as diglyceride with high specific activity γ-[32P]ATP, and the two products are differentiated by their alkali stability. This method was applied to the detection of endogenous phospholipases and sphingolipases in several membrane systems and could have wide application.
MIXOR: a computer program for mixed-effects ordinal regression analysis

MIXOR provides maximum marginal likelihood estimates for mixed-effects ordinal probit, logistic, and complementary log-log regression models. These models can be used for analysis of dichotomous and ordinal outcomes from either a clustered or longitudinal design. For clustered data, the mixed-effects model assumes that data within clusters are dependent. The degree of dependency is jointly estimated with the usual model parameters, thus adjusting for dependence resulting from clustering of the data. Similarly, for longitudinal data, the mixed-effects approach can allow for individual-varying intercepts and slopes across time, and can estimate the degree to which these time-related effects vary in the population of individuals. MIXOR uses marginal maximum likelihood estimation, utilizing a Fisher-scoring solution. For the scoring solution, the Cholesky factor of the random-effects variance-covariance matrix is estimated, along with the effects of model covariates. Examples illustrating usage and features of MIXOR are provided.
Using behavior rating scales for ADHD across ethnic groups: The IOWA Conners.

In this study we examined the normative and construct equivalence of the teacher IOWA Conners Rating Scale (IOWA) in a sample of 3,998 elementary school children (2,124 African American and 1,874 European American) ages 5 to 11 years in an urban school district. Risk odds ratios (% > 2 SD) were calculated by gender and ethnicity. An exploratory Principal Axis factor analysis was performed to determine the appropriateness of the 2-factor model. Structural equation modeling was used to estimate the degree of fit for the 2-factor model. Both African American boys and girls received significantly higher scores than their European American counterpoints.There was a 2.48 to 3.51 greater likelihood forAfrican American boys and a 3.60 to 5.27 greater likelihood of African American girls to be rated > 2 SD above the mean for inattention/overactivity, aggression, or IOWA Conners Rating Scale scores. A rater ethnicity by student ethnicity (European American vs. African American) interaction was also found. Confirmatory factor analysis indicated that the same 2-factor model was appropriate for the African American and European American groups. The results suggest that although there is construct equivalence across the African American and European American groups, there is still a question as to normative equivalence.
The pharmacology of post-trial memory processing in septum

The septum is recognized as important in learning and memory, but relatively little is known about the role of specific neurotransmitter receptors in memory processing in the septum. We evaluated the role of the classical neurotransmitters in mice that were prepared for intraseptal microinfusion of drug solution after footshock avoidance training in T-maze. Retention for the footshock training was determined 1 week after training and drug administration. The results indicated that receptor agonists of dopamine, norepinephrine, glutamate and acetylcholine improved retention, while the antagonists impaired retention. Receptor agonists of serotonin, γ-amino butyric acid (GABA) and opioids impaired retention, while antagonists improved retention.
Effects of chlorine dioxide on thyroid function in neonatal rats.

Chlorine dioxide (ClO2), an alternative to chlorine for drinking water disinfection, has been implicated as a potential antithyroid agent (Bercz et al., 1982). Because antithyroid compounds are known to alter neurobehavioral development, the present study was designed to determine if perinatal exposure to ClO2 affects behavioral activity in rat pups. The activity cage system was designed to monitor the development of locomotor activity of a litter of pups between ages 14-21 d. Pups were exposed to ClO2 either directly, by gavaging 14 mg/kg . from age 5 to 20 d, or indirectly via their dams' drinking water in concentrations of 2, 20, or 100 mg/l from gestation to weaning (21 d postpartum). Although the activity of the indirectly exposed group was not different from controls, the gavaged group showed significantly depressed activity for d 18 and 19 postpartum. The T4 levels of the 21-d-old pups was significantly depressed in the 100-mg/l ClO2 group. The gavaged pups showed an even greater T4 depression, which correlates with their activity levels. These data support the hypothesis that ClO2 affects thyroid function and suggests that a slight depression in T4 can result in developmental delays.
Development of a screening and recruitment registry to facilitate perinatal depression research in obstetrics settings in the USA.

Abstract Objective To create a multi-site registry to enable future large-scale studies of perinatal depression among women attending obstetrics clinics in the USA. Methods A screening and recruitment registry was developed that included women aged at least 18 years who attended seven obstetric clinics in the University of Michigan Health System (Ann Arbor, MI, USA) for prenatal care between September 8, 2008, and June 9, 2011. Participants completed depression screening and research recruitment materials. Results Of 4745 women who returned a screening form, 2983 had completed it, giving an overall agreement rate of 62.9%. A total of 630 participants were enrolled into ten research studies via the registry. Among the 2982 women for whom scores on the Edinburgh Postnatal Depression Scale were available, 494 (16.6%) fell within the at-risk range or had scores suggestive of clinical depression. Conclusion The present registry could improve detection of perinatal depression symptoms and potentially serve as a model for dissemination and implementation at other sites with an interest in studying factors linked to perinatal depression.
Sickle-cell anemia and other hemoglobinopathies. Procedures and strategy for screening employing spots of blood on filter paper as specimens.

Abstract Since blood spots on filter paper are routinely collected in many areas for phenylketonuria testing of newborn infants, we developed several methods for detecting sickle-cell disease and other hemoglobinopathies using this type of specimen. Simple, inexpensive modifications of cellulose acetate electrophoresis plus citrate-agar and globin-chain electrophoresis are employed, permitting one technician to screen as many as 500 specimens per day at a material cost of $0.03 per specimen. (N Engl J Med 288:1265–1268, 1973)
High-resolution photoelectron spectroscopy through deconvolution

Abstract A new iterative deconvolution algorithm for the development of very high resolution Hc(I)-excited photoelectron spectra of gases is presented. The algorithm accepts as input a medium-resolution spectrum and an instrument function obtained by scanning intrinsically narrow line (e.g. the Ar 2 P 3/2 line) under conditions identical to those used to acquire the medium resolution spectrum. The deconvolved partial spectrum of an O 2 H 2 O mixture is presented as a test case prior to presentation of results for three nitrogen lines. For comparison purposes directly obtained high-resolution spectra of the nitrogen lines are included. The shapes of the nitrogen lines are discussed within the framework of a one-center expansion theory of photoionization. The conditions under which deconvolution can be profitably applied are briefly discussed and an attempt is made to establish the deconvolution (contrary to still popular belief) is not in any way equivalent to curve fitting.
An open source infrastructure for managing knowledge and finding potential collaborators in a domain-specific subset of PubMed, with an example from human genome epidemiology

Identifying relevant research in an ever-growing body of published literature is becoming increasingly difficult. Establishing domain-specific knowledge bases may be a more effective and efficient way to manage and query information within specific biomedical fields. Adopting controlled vocabulary is a critical step toward data integration and interoperability in any information system. We present an open source infrastructure that provides a powerful capacity for managing and mining data within a domain-specific knowledge base. As a practical application of our infrastructure, we presented two applications – Literature Finder and Investigator Browser – as well as a tool set for automating the data curating process for the human genome published literature database. The design of this infrastructure makes the system potentially extensible to other data sources. Information retrieval and usability tests demonstrated that the system had high rates of recall and precision, 90% and 93% respectively. The system was easy to learn, easy to use, reasonably speedy and effective. The open source system infrastructure presented in this paper provides a novel approach to managing and querying information and knowledge from domain-specific PubMed data. Using the controlled vocabulary UMLS enhanced data integration and interoperability and the extensibility of the system. In addition, by using MVC-based design and Java as a platform-independent programming language, this system provides a potential infrastructure for any domain-specific knowledge base in the biomedical field.
Participation's place in rural development: seeking clarity through specificity.

Abstract Over the past few years, development specialists have expressed increasing concern over the lack of progress in altering the plight of the rural poor. Towards this end they are shifting from the capital-investment growth models of the 1960s to the more people-centred basic- needs approaches that are increasingly dominating development thinking in the 1970s. In the process, they are turning to a number of related development strategies, one of the most important and least understood of which is ‘popular participation’. Increasing numbers of studies and activities are being undertaken to bolster government and donor capacity to promote participation in development programmes. Yet, with all these activities the disturbing fact is that there is little agreement on what participation is or on its basic dimensions. This article seeks to provide some order to the emergence of participatory concerns in the development literature, and to offer a carefully elaborated framework that clarifies the notion of ‘rural-development participation’ and make it applicable to total-development projects.
Renal pathology associated with hematopoietic stem cell transplantation.

The kidney is subject to a large variety of injurious factors before, during, and after hematopoietic stem cell transplantation (HCT), leading to a high incidence of acute kidney injury in the peritransplant period. Chronic kidney disease is estimated to impact 15% to 20% of HCT recipients. Although
THE ROLE OF PUBLIC CAPITAL IN THE ECONOMIC DEVELOPMENT PROCESS

This paper reviews the evidence of public infrastructure's impact on economic development. The evidence indicates the marginal net social returns is low. The paper also examines the effect of economic, demographic, and political forces on infrastructure investment. Finally, the literature suggests that improving maintenance and reducing congestion can greatly increase the benefits from the existing public capital stock.
Acute effects of nicotine on serum glucose insulin growth hormone and cortisol in healthy smokers.

Cigarette smoking impairs glucose tolerance and alters serum levels of hormones involved in glucose metabolism, but the role of nicotine in such hormonal alterations is not well understood. In order to isolate the effects of transdermal nicotine on serum glucose, insulin, growth hormone, and cortisol in smokers, we conducted a randomized double-blind placebo-controlled cross-over study involving 34 healthy volunteer smokers between 18 and 55 years of age. Administration of a 14-mg transdermal nicotine patch resulted in nonsignificantly lowered fasting quantitative insulin-sensitivity index (P = .11) and a nonsignificant 9.3-mg/dL mean increase in serum glucose levels during a 75-g oral glucose tolerance test (OGTT) at time 60 minutes (P = .12). There were no substantial differences between groups in the areas under the curve (AUCs) for glucose (P = .33) or insulin (P = .79) during the OGTT. Levels of insulin and cortisol also were not significantly altered by nicotine. A secondary finding observed in the overall study group (primarily in females) was that nicotine caused a 29% median decrease in serum growth hormone (P = .02). We conclude that nicotine patches may lead to mild hyperglycemia and lowered insulin sensitivity. Further research is needed to determine the clinical implications of the unexpected finding that nicotine decreased growth hormone levels in female smokers.
Effects of successive bilateral hippocampectomy on DRL 20 performance in rats.

Abstract The effects of single-stage versus two-stage, successive bilateral hippocampectomy on acquisition of a DRL 20 operant schedule were determined. Rats received training on a continuous reinforcement operant schedule prior to either single-stage total hippocampectomy, sham operative treatment or bilateral lesion of either dorsolateral or posteroventral hippocampus. After forty days of DRL 20 training, the seriatim groups received bilateral lesions of remaining hippocampal tissue. All animals then received fifteen final days of DRL 20 training. The single-stage lesion group was found, for all sessions, to be significantly less efficient than the sham operates. During interoperative training the two seriatim groups were equally efficient and did not differ from the sham operates. However, after the second serial lesion, the group that had received an initial lesion of the posteroventral hippocampus decreased DRL performance to a level equal to that of the single-stage group while the group which had initially received anterodorsal lesions maintained efficient DRL performance.
PREPARATION OF SINTERED PYREX GLASS AERATORS FOR USE IN WATER CULTURE EXPERIMENTS WITH PLANTS.

In growing plants under water culture conditions it is frequently important, and sometimes indispensable, to pass air under pressure through the solutions. Such aeration has a profound influence on root development. A practical problem arises of providing means for the uniform distribution of air through the culture solution, especially when tanks or other large containers are employed. In some experiments it is also necessary that the aeration devices shall not yield impurities to the solution ; for example, in the study of the effects of elements required by the plant in minute quantity. It has been found essential to the work of this laboratory to provide extensive facilities for aeration in the greenhouse. Several methods of distributing air were devised but were eliminated for various reasons. Among the devices used were surgical rubber tubing; porous porcelain, alundum, and block tin tubing; Folin tubes; and carborundum blocks. Surgical rubber tubing with a soft smooth wall, pierced with fine needle holes, aerated solutions fairly well, but was discarded because of its rapid deterioration, uneven aeration, and compositional impurities. Block tin tubing, drilled with small holes, was rejected because of uneven aeration and possible toxicity. The principal objections to alundum, porcelain, and carborundum were mechanical unsuitability and possible presence of impurities, both in the aerators and in the connections necessarily employed. Since inert, resistant units of uniform quality1 and capable of dispersing the air in fine bubbles were essential, pyrex glass was finally chosen as a suitable medium through which air could be distributed without encountering the objections mentioned. Glass aerators of the type needed were not obtainable on the market, and as methods described in the literature were not applicable to our requirements, it was necessary to develop one. Many modifications of sintered glass aerators were tried, such as sintered disks sealed into glass tubing of various sizes and shapes, and tubing constructed entirely of sintered glass. Individually these were satisfactory in operation, but could not be economically produced in large quantities and it was difficult to obtain even aeration throughout a group of aerators. The method finally devised incorporates the sintering and sealing in one operation. The resulting aerator is efficient, rapidly and easily made in large quantities, and readily cleaned.
Sex Ratios in Poultry

Abstract A study was made of the sex distribution of 1514 chicks hatched at this station during February, March, April, and May, 1922. These chicks were hatched from our S. C. W. Leghorn, Barred Rock, and S. C. R. I. Red pedigreed breeding pens, all normal eggs produced during the breeding season being incubated. Sex of all chicks hatched was determined, and is included in the data. Jull 1 reports the sex ratio of fowl as given by Darwin to be 48.64 per cent, by Pearl to be 48.57 per cent, and based on his own investigations to be 48.82 per cent. The term “sex ratio” Jull defines as the proportion of males in a total population of one hundred individuals. Our data indicate the following distribution of sex, including all three varieties and all matings observed : Number of Chicks Number Males Sex Ratio 1514 791 52.24% The possibility of sex . . .
Energy storage problems

W I D E S P R E A D use of solar energy or wind power, except for irrigation, depends on finding practical ways of storing the energy or products. Research on the product ion and storage of solar energy is new t)eeause there has not been suflMent incentive. Countries best able to under take research and development in these fields have had an ample supply of combust ion fuels and have had little need for new sources of energy. The field of solar-energy storage is so new in impor tance tha t discussions of economic applications at present must be based on limited experimental and engineering data. They will have to be aimed at geographical areas where there is not now an adequate supply of fuel and conventional electric power. In considering the economics of solar and wind energy product ion and storage, it is impor tan t to realize that. the conditions of the highly industrialized countries do not apply and tha t capital investment and foreign exchange are difficult to obtain and tha t labor m a y be relatively abundant . I t is impor tant to emphasize also tha t we cannot th ink in terms of producing eleetricity for less than one cent per k i lowat thour as is done in the large, efficient electrical power plants of the highly industrialized nations. I t is not reasonable to compare the cost of e lec t rMty produced in solar units of one kilowatt with tha t produced in 100,000-kilowatt units of the conventional type. Stored electricity from tile sun or wind can be produced in small units of the order of kilowatts, and without large capital investment . Moreover, there is a considerable saving in the cost of transmission lines and distr ibution to m a n y small users. The cost of stored electrical or mechanical energy can be considerably greater than the cost of the energy produced directly, because of the inefficiency and the cost of the storage, and later release of the stored energy. The total cost 1' of one ki lowat thour of eleelrieal energy delivered from storage can })e expressed in the following terms :
The period-pulse-width distribution of pulsars and their division into three classes.

The period-pulse-width (P-W) distribution of sample of 41 pulsars has been reanalyzed under two versions of a model where radiation is beamed from magnetic polar caps which are isotropically oriented with respect to the rotation axis of the neutron stars (IOPC models). It is found that neither IOPC model can explain the P-W distribution of the entire sample. Pulsars with simple unimodal (U) or complicated multimodal (M) pulse shapes show significantly different P-W distributions. Class M pulsars have a narrower P-W distribution than do class U pulsars and, taken separately, are compatible with either IOPC model. Class U pulsars divide into two subgroups, those with relatively narrower pulses (UN) and those with relatively wider pulses (UW), each of which is compatible with either IOPC model. One interpretation of these results is that the pulsars in classes UN, M, and UW have different intrinsic beam sizes, roughly in the ratios 1:2:4, respectively. The possible origins of the three classes are discussed in terms of the force-balance magnetosphere model (Roberts et al., 1972, 1973), where the differences may be attributed to different-mass neutron stars and the structure of the polar caps. An alternative interpretation is that the angle between the rotation and emission axes is not isotropically distributed, but can take only certain preferred values.
High-performance liquid chromatographic method for the determination of salicylic acid and its metabolites in urine by direct injection.

Abstract A direct injection method has been developed for the determination of salicylic acid and its metabolites in urine. Urine samples are treated with hydroxylamine to convert salicyl acyl glucuronide to salicylhydroxamic acid, which can be accurately quantitated by direct injection into a high-performance liquid chromatographic system along with salicylic acid, gentisic acid and salicyluric acid. Salicyl phenolic glucuronide is quantitated by difference after hydrochloric acid hydrolysis at 65°C with no loss of salicylic acid by sublimation or hydrolytic loss of salicyluric acid. This method has been applied to urine samples from human subjects and the results are discussed.
Symmetrical cleavage of the metal-metal bond in decacarbonyldirhenium(0) by ultraviolet irradiation

Abstract A study of the photoreaction of Re 2 (CO) 10 with carbon tetrachloride has provided evidence supporting efficient symmetrical metal-metal bond scission upon photoexcitation of the rhenium carbonyl.
Criteria of interplanetary parameters causing intense magnetic storms (Dst < −100 nT)

Abstract Ten intense magnetic storms (Dst 5 mV m−1, that last for intervals >3 h. Because we find a one-to-one relationship between these interplanetary events and intense storms, we suggest that these criteria can, in the future, be used as predictors of intense storms by an interplanetary monitor such as ISEE-3. These Bz events are found to occur in association with large amplitudes of the IMF (magnitude 13–30 nT) within 2 days after the onset of either high-speed solar wind streams or of solar wind density enhancement events, giving important clues to their interplanetary origin. Some obvious possibilities will be discussed. The close proximity of the Bz events and magnetic storms to the onset of high speed streams or density enhancement events is in sharp contrast to interplanetary Alfven waves and HILDCAA events previously reported by the authors (Tsurutani and Gonzalez, 1986, Planet. Space Sci.35, 405) and thus the two interplanetary features and corresponding geomagnetic responses can be thought of as being complementary in nature. An examination of opposite polarity (northward) Bz events with the same criteria (Bz > 10 nT, with dawn ward-electric fields >5 mV m−1, that last for intervals >3 h) shows that their occurrence is similar both in number as well as in their relationship to interplanetary disturbances, and that they lead to low levels of geomagnetic activity. Although 90% of the events were associated with high-speed streams and interplanetary shocks, the amplitude of the storms had little dependence on the strength of the shocks.
Presidential Nominations and Coalition Theory

Contemporary literature postulates that the success of candidate nomination efforts is closely tied to the "rules of the game." Contrary to this view, the authors contend that important variables intercede between the rules and candidate nomination. These vari ables fall under the umbrella of coalition theory. As applied in the article, coalition theory suggests that a presidential nomination is achieved if several qualifying criteria are ad dressed and met. The successful candidate must have the support of his home state delegation, a strong regional base, and continuous momentum. With respect to the 1976 nominating events, the authors conclude that coalition theory helps to explain success or failure in securing the presidential nomination. Moreover, the analysis indicates that both nominees would have triumphed under two alternate sets of nomination rules by following the strategy suggested by coalition theory. These findings have important implications for future contests.
The vertical microstructure of temperature and salinity

Abstract Measurements with a high resolution probe on a free fall vehicle have sensed temperature and salinity fluctuations in the millimeter range and permitted calculation of the vertical density profile to scales of 2 cm. Observations between 210 and 340 m off San Diego show that features larger than several meters are stably stratified, implying that the numerous temperature inversions must be formed by lateral advection. The temperature inversions have been resolved into several gravitationally stable layers separated by sharp interfaces a few centimeters thick. These sharp steps of increasing temperature and salinity are attributed to the instability which results from the differential diffusion of heat and salt across an interface formed by warm saline water underlying colder fresher water. Numerous instabilities have been found with length scales less than 1 m and continuing down to the limit of resolution of Vaisala's frequency. Features of another type are suggestive of local overturning driven by mechanical forces.
A distributed, dynamic, parallel computational model: the role of noise in velocity storage

Networks of neurons perform complex calculations using distributed, parallel computation, including dynamic “real-time” calculations required for motion control. The brain must combine sensory signals to estimate the motion of body parts using imperfect information from noisy neurons. Models and experiments suggest that the brain sometimes optimally minimizes the influence of noise, although it remains unclear when and precisely how neurons perform such optimal computations. To investigate, we created a model of velocity storage based on a relatively new technique–“particle filtering”–that is both distributed and parallel. It extends existing observer and Kalman filter models of vestibular processing by simulating the observer model many times in parallel with noise added. During simulation, the variance of the particles defining the estimator state is used to compute the particle filter gain. We applied our model to estimate one-dimensional angular velocity during yaw rotation, which yielded estimates for the velocity storage time constant, afferent noise, and perceptual noise that matched experimental data. We also found that the velocity storage time constant was Bayesian optimal by comparing the estimate of our particle filter with the estimate of the Kalman filter, which is optimal. The particle filter demonstrated a reduced velocity storage time constant when afferent noise increased, which mimics what is known about aminoglycoside ablation of semicircular canal hair cells. This model helps bridge the gap between parallel distributed neural computation and systems-level behavioral responses like the vestibuloocular response and perception.
A computational model of the temporal dynamics of plasticity in procedural learning: sensitivity to feedback timing

The evidence is now good that different memory systems mediate the learning of different types of category structures. In particular, declarative memory dominates rule-based (RB) category learning and procedural memory dominates information-integration (II) category learning. For example, several studies have reported that feedback timing is critical for II category learning, but not for RB category learning – results that have broad support within the memory systems literature. Specifically, II category learning has been shown to be best with feedback delays of 500ms compared to delays of 0 and 1000ms, and highly impaired with delays of 2.5 seconds or longer. In contrast, RB learning is unaffected by any feedback delay up to 10 seconds. We propose a neurobiologically detailed theory of procedural learning that is sensitive to different feedback delays. The theory assumes that procedural learning is mediated by plasticity at cortical-striatal synapses that are modified by dopamine-mediated reinforcement learning. The model captures the time-course of the biochemical events in the striatum that cause synaptic plasticity, and thereby accounts for the empirical effects of various feedback delays on II category learning.
Microscopic behavior of single corrosion pits : the effect of thiosulfate on corrosion of stainless steel in NaCl

Abstract Pitting corrosion of Type 304 and 316 stainless steels was investigated in neutral chloride solutions containing various concentrations of thiosulfate (0.01 to 500 mM) and chloride (1 to 1000 mM). The effect of thiosulfate on pitting corrosion of stainless steel 304 was quantitatively studied at the microscopic level by initiating single pits on small wires in neutral chloride solutions containing thiosulfate. Analysis of single pit data indicated that thiosulfate may promote stability through either a cathodic side-reaction or through the existence of a salt film. In galvanostatic experiments, the potential response exhibited six types of behavior that depended on the concentrations of chloride and thiosulfate. Thiosulfate was found to promote the sustained growth, or stability, of pits within a concentration range that depended upon the concentration of chloride ion. An excess of thiosulfate prevented pit formation. Type 316 stainless steel required higher concentrations of thiosulfate to produce stable pits, as compared to Type 304. The effect of surface adsorption of thiosulfate on pitting of 316 stainless steel was investigated by an in situ radiotracer method. It was found that the extent of thiosulfate surface adsorption differed for the three levels of chloride in 0.1 mM Na 2 S 2 O 3 , and that an increase in the surface concentration of thiosulfate from the small pit region caused formation of large pits.
Terahertz frequency optical constants of montmorillonite

The real and imaginary parts of the complex index of refraction of montmorillonite between 0.2 THz and 1.4 THz at room temperature are reported. The optical properties of montmorillonite in this frequency range were experimentally determined using time-domain THz spectroscopy. Distinct frequency dependencies of the index of refraction and the extinction coefficient are not observed within the uncertainties of the measurements. The index of refraction of montmorillonite is modeled using effective medium theory.
Vapor transport and thermodynamic equilibria in the germanium-gallium-iodine system☆☆☆

Abstract Thermodynamic information is used to correlate the composition of germanium-gallium solid solutions with the temperature, pressure and composition of a gas mixture with which the solid is in equilibrium. At temperatures below 1000°K, and gallium concentrations in excess of 10 16 atoms cm 3 of solid,the dominant gas phase species are GaI, GeI2 and GaI3 with the mole fraction of GeI2 in the gas mixture becoming very small at gallium concentrations greater than 1018 atoms cm−3 and temperatures below 900°K. Epitaxial gallium doped germanium layers were grown and their composition found to be close to the calculated equilibrium composition. The growth rate agreed quantitatively with that predicted on the assumption that gaseous diffusion was the rate limiting process. The very low mole fraction of GeI2 prevents rapid quasi equilibrium single crystal growth of heavily doped material at low temperatures.
Ultracytopathological characterization of leaves following short-term exposures of hydrogen chloride gas

Abstract An ultrastructural investigation was conducted to determine the cells and structures in leaves of Phaseolus vulgaris that were affected by short term exposures to gaseous hydrogen chloride. Primary leaf tissues were sampled 24 h after exposure to approx 25 mg HCl m −3 for 20 min. We noted conformational alterations in mitochondria and chloroplasts, cytoplasmic membrane disruption and vesiculation, accumulation of a particulate electron dense material in vacuoles and vesicles, and the elaboration of densely staining globules within fumigated tissues. Most of the severely or totally disrupted cells were confined to the abaxial epidermis.
The spectrum of congenital myasthenic syndromes

The past decade saw remarkable advances in defining the molecular and genetic basis of the congenital myasthenic syndromes. These advances would not have been possible without antecedent clinical observations, electrophysiologic analysis, and careful morphologic studies that pointed to candidate genes or proteins. For example, a kinetic abnormality of the acetylcholine receptor (AChR) detected at the single channel level pointed to a kinetic mutation in an AChR subunit; endplate AChR deficiency suggested mutations residing in an AChR subunit or in rapsyn; absence of acetylcholinesterase (AChE) from the endplate predicted mutations in the catalytic or collagen-tailed subunit of this enzyme; and a history of abrupt episodes of apnea associated with a stimulation dependent decrease of endplate potentials and currents implicated proteins concerned with ACh resynthesis or vesicular filling. Discovery of mutations in endplate-specific proteins also prompted expression studies that afforded proof of pathogenicity, provided clues for rational therapy, lead to precise structure function correlations, and highlighted functionally significant residues or molecular domains that previous systematic mutagenesis studies had failed to detect. An overview of the spectrum of the congenital myasthenic syndromes suggests that most are caused by mutations in AChR subunits, and particularly in the ɛ subunit. Future studies will likely uncover new types of CMS that reside in molecules governing quantal release, organization of the synaptic basal lamina, and expression and aggregation of AChR on the postsynaptic junctional folds.
Three-dimensional model for the hormone binding domains of steroid receptors

Abstract We have used a motif-based structural search method to identify structural homologs of the hormone binding domains of the nuclear receptors from among a set of known protein structures and have found the closest similarity with members of the subtilisin-like serine proteases. These proteins consist of an open twisted sheet of parallel beta-strands flanked on both sides by alpha-helices. The alignment with the protease scaffold was refined by using multiple sequence prealignment of different sets of nuclear receptors, and alternative model structures were screened by considering their consistency with the results of biochemical experiments defining the ligand binding pocket. In the most favored model, nearly all of the residues thought to be involved in ligand binding map to a pocket of appropriate dimensions where the subtilisin-like proteases have their active site. The three-dimensional model that we propose for the hormone binding domains of the nuclear receptors provides a framework for the design of experiments to further investigate nuclear receptor structure and function.
DESIGN AND FABRICATION OF A MICRO-CPL FOR CHIP-LEVEL COOLING

This paper summarizes the development of a micro-CPL designed for chip-level cooling. This research indicates that there are numerous fundamental issues regarding the thermofluid dynamics at small scales that are poorly understood. These issues, which can often be ignored at macroscales, will be critical as devices such as micro-CPL’s and heat pipes are optimized in order to handle the increasingly large thermal loads of modern technology.
The University in Africa: Reflections on Epistemic Decolonisation

(2007). The University in Africa: Reflections on Epistemic Decolonisation. Social Dynamics: Vol. 33, No. 1, pp. 206-211.