cssi/SciSciGPT-SciSciNet huggingface dataset:
Surgery is not considered women's work: gender bias in oral presentations in gynecologic surgery conferences

Objectives: Gender bias towards surgery as a ‘male’ profession has been previously described. We sought to examine gender differences among medical and surgical presentations at gynecologic surgery (GS) conferences. Methods: An Institutional Review Board (IRB)-exempt, observational study of oral conference presentations was conducted. Programs from seven GS conferences in 2019 were examined and 490 oral presentations were categorized by three independent reviewers as primarily medical (discussing therapeutics, medications, non-surgical options) or surgical (procedural or surgical). After categorization of abstracts, presenting author speakers’ gender was identified using publicly available institutional data to determine author pronouns. One sample proportion Z tests were used to compare presenter gender to the expected representation of 58% in obstetrics and gynecology (OBG), and 84% of OBG trainees. Chi-square tests assessed differences between medical and surgical talks within the same conference and across meetings. Results: In 2019, 64.5% of plenaries in internationally-acclaimed GS conferences were delivered by women. This proportion was greater than the percentage (58%) of OBG physicians who are women (p=0.003); but less than the percentage of women in training (84%, p Download : Download high-res image (93KB) Download : Download full-size image Conclusions: Presentations by women are common at scientific GS meetings. However, a bias towards women presenting medical abstracts while men presenting surgical abstracts was identified. This differed at international conferences where women were less likely to present, but a gender division of medical and surgical abstracts was not identified. Despite high percentages of women, bias towards surgery as a male professional activity persists in gynecology.
Transdiagnostic dimensions of anxiety: Neural mechanisms, executive functions, and new directions

Converging neuroscientific and psychological evidence points to several transdiagnostic factors that cut across DSM-defined disorders, which both affect and are affected by executive dysfunction. Two of these factors, anxious apprehension and anxious arousal, have helped bridge the gap between psychological and neurobiological models of anxiety. The present integration of diverse findings advances an understanding of the relationships between these transdiagnostic anxiety dimensions, their interactions with each other and executive function, and their neural mechanisms. Additionally, a discussion is provided concerning how these constructs fit within the Research Domain Criteria (RDoC) matrix developed by the National Institutes of Mental Health and how they relate to other anxiety constructs studied with different methods and at other units of analysis. Suggestions for future research are offered, including how to (1) improve measurement and delineation of these constructs, (2) use new neuroimaging methods and theoretical approaches of how the brain functions to build neural mechanistic models of these constructs, and (3) advance understanding of the relationships of these constructs to diverse emotional phenomena and executive functions.
Brain-Derived Neurotrophic Factor val66met Polymorphism Affects Human Memory-Related Hippocampal Activity and Predicts Memory Performance

BDNF plays a critical role in activity-dependent neuroplasticity underlying learning and memory in the hippocampus. A frequent single nucleotide polymorphism in the targeting region of the human BDNF gene (val66met) has been associated with abnormal intracellular trafficking and regulated secretion of BDNF in cultured hippocampal neurons transfected with the met allele. In addition, the met allele has been associated with abnormal hippocampal neuronal function as well as impaired episodic memory in human subjects, but a direct effect of BDNF alleles on hippocampal processing of memory has not been demonstrated. We studied the relationship of the BDNF val66met genotype and hippocampal activity during episodic memory processing using blood oxygenation level-dependent functional magnetic resonance imaging and a declarative memory task in healthy individuals. Met carriers exhibited relatively diminished hippocampal engagement in comparison with val homozygotes during both encoding and retrieval processes. Remarkably, the interaction between the BDNF val66met genotype and the hippocampal response during encoding accounted for 25% of the total variation in recognition memory performance. These data implicate a specific genetic mechanism for substantial normal variation in human declarative memory and suggest that the basic effects of BDNF signaling on hippocampal function in experimental animals are important in humans.
Whole Body Magnetic Resonance Angiography

The sections in this article are 1 Introduction 2 The Effects of Motion 3 Motion Compensation 4 Flow Measurement 5 MRA of the Entire Body 6 Future Directions 7 Biographical Sketches Related Articles
Intraoperative radiocolloid injection for sentinel node biopsy postneoadjuvant chemotherapy.

Abstract Background This study sought to determine significance of radiocolloid injection timing for sentinel node biopsy (SNB) after neoadjuvant chemotherapy (NAC). Material and methods A retrospective comparison of intraoperative (IRCI) and preoperative (PRCI) radiocolloid injection for SNB was performed in breast cancer patients who had completed NAC. The sentinel node identification rate (SNIDR) was tested for noninferiority by a two-proportion z -test. The differences between clinical demographics, pathologic demographics, and SNIDR were evaluated by Fisher exact test. The difference in the number of sentinel nodes removed was analyzed by two-sample t -test. Results In the 6-y study period, 120 SNB were performed after NAC: 84 received PRCI and 36 received IRCI. The two groups were similar except there were fewer clinical T2 and more clinical T3 and T4 with IRCI ( P = 0.0008). The SNIDR was 92.9% with PRCI and 80.6% with IRCI. By two-proportion z -test, IRCI was not “noninferior” ( P = 0.5179). By Fisher exact test, the SNIDR of the two groups did not differ. The SNIDR differs only in patients who experience T downstaging (100% versus 80%, P = 0.0173). The mean number of lymph nodes removed was higher with IRCI: 3.38 versus 2.49 nodes ( P = 0.0068). There were more positive SNB with IRCI: 32.1% versus 55.2%, ( P = 0.0432). The incidence of nontherapeutic axillary dissection was similar between the two groups (3.6% for PRCI versus 5.6% for IRCI). Conclusions IRCI for SNB after NAC may be inferior to PRCI.
The Assessment: Technology Policy

Current research and problems in science and technology policy are reviewed. Trends in innovative activity in the G-7 economies during the past two decades are summarized and the economic rationale for policy in this area given. Policy tools currently in use in many countries include tax credits and subsidies, the intellectual property system, and competition policy. Ongoing areas of current controversy are the interaction of intellectual property and competition policies, environmental and innovation policy, standard-setting in industries characterized by network externalities, and the privatization of scientific research and its consequences. Copyright 2002, Oxford University Press.
The Contribution of Parent and Peer Support to Head Start Children's Early School Adjustment.

Abstract The research involved a prospective longitudinal study of the relationship of parent and peer support to gains over the school year in Head Start children's cognitive and social competence. Sixty three children enrolled in Head Start centers in a rural county in northern California participated in the study during the fall and spring of the school year. Parental involvement in school was predictive of gains in learning skills and classroom behavior, whereas mutual friendship predicted gains in social play and cooperative pretend play. Initial peer play skills were also predictive of later mutual friendship and peer preference, suggesting bi-directional influence between peer competence and peer social support.
Effects of chloroquine and 4,4'-bis(diethylaminoethoxy)α,β-diethyldiphenylethane on the incorporation of [3H]glycerol into the phospholipids of rat liver lysosomes and other subcellular fractions, in vivo

Oral treatment of rats with 100 mg/kg chloroquine or 4,4'-bis(diethylaminoethoxy)α,β-diethyldiphenylethane for one week causes phospholipid storage in liver and other tissues. The mechanism of this drug-induced lipidosis is not fully understood although several hypotheses have been advanced. In these studies [1,3-3H]glycerol was injected intravenously into control rats and into chloroquine and 4,4'-bis(diethylaminoethoxy)α,β-diethyldiphenylethane-treated rats. The [3H]glycerol was incorporated into phospholipids by de novo synthesis in liver microsomes and transferred to other intracellular membranes which lack the capacity for de novo synthesis of phospholipids. Liver microsomes, mitochondria and lysosomes were isolated and the incorporation of [3H]glycerol into phosphoglycerides was determined as a function of time. Treatment with chloroquine or 4,4'-bis(diethylaminoethoxy)α,β-diethyldiphenylethane results in greatly enhanced incorporation of [3H]glycerol into lysosomal phospholipids in spite of the fact that the incorporation of [3H]glycerol into microsomal phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol by de novo synthesis is reduced. Phosphatidylglycerol, a precursor of lysosomal bis(monoacylglycerol)phosphate, is labeled at a greatly increased rate, especially in liver microsomes from chloroquine- or 4,4'-bis(diethylaminoethoxy)α,β-diethyldiphenylethane-treated rats, while the incorporation of [3H]glycerol into phosphatidylinositol in microsomes is reduced. Since both phosphatidylinositol and phosphatidylglycerol are formed from CDP-diacylglycerol, the enhanced incorporation of [3H]-glycerol into phosphatidylglycerol cannot be due only to inhibition of phosphatidate phosphohydrolase by these two cationic amphiphilic agents suggesting the possibility of a specific effect of these drugs on phosphatidylglycerol metabolism in liver. [3H]Glycerol incorporation into bis(monoacylglycero)phosphate is found only in lysosomes in agreement with our earlier observations. The results suggest increased transfer of newly-synthesized microsomal phospholipids to lysosomes and/or decreased lysosomal catabolism of phospholipids in chloroquine- and 4,4'-bis(diethylaminoethoxy)α,β-diethyldiphenylethane-treated rat liver. Incorporation of newly-formed 3H-labeled phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol into mitochondria is not increased, indicating that a non-specific increase in intracellular phospholipid exchange is not responsible for our observations.
Effect of gain and index nonlinearities on single-mode dynamics in semiconductor lasers

The finite intraband relaxation time in semiconductor lasers leads to gain saturation at high laser powers. The nonperturbative solution of the single-mode density-matrix equations shows that both the optical gain and the refractive index become intensity dependent as a result of intraband relaxation dynamics. Gain and index nonlinearities are included in the rate equations, and how the modulation response and noise characteristics of semiconductor lasers are affected by such nonlinearities is studied. The intensity dependence of the frequency and the damping rate of relaxation oscillations leads to a fundamental limit imposed on the small-signal modulation bandwidth; the analysis provides an expression for the ultimate modulation bandwidth in terms of the material parameters. >
STROKE SYNDROME IN SICKLE CELL DISEASE (SCD)

To delineate the natural progression of cerebral vascular accidents in SCD and to determine the resultant structural and functional defects we investigated 29 patients (27 SS, 2 SC) who sustained strokes. Subarachnoid or intra-cerebral hemorrhage and bone marrow embolism occurred in 9 patients ages 14-35 years. Cerebral infarction occurred in 20 (19 SS, 1 SC) with a modal age of onset of 5 years. We were able to evaluate 14 long term survivors who were observed for a mean period of 9.4 years following the initial stroke. 10 (71%) had 1 or more recurrences with a mean interstroke interval of 28 months. Residual functional impairment was noted in all 14. Computerized axial tomography on 9 showed areas of low density and ventricular dilatation indicating structural brain damage. These patients were not treated with a transfusion program. Their clinical course indicates that evaluation of such therapy requires long periods of observation.
Time-course Study of Translocation of Products of Photosynthesis in Soybean Plants

In a previous report (7) we have shown that soybean plants, in response to age and culture conditions, selectively translocate varying proportions of C14labeled sucrose, serine-glycine, and malic acid from among the products of photosynthesis in a primary leaf exposed to C1402 for 10 minutes. Regardless of age or culture conditions or the amount or type of compound exported, total radioactivity in the stem decreased logarithmically with distance from the input node to the root. Moreover, the concentration of radioactivity at the input node did not vary significantly in spite of some relatively large changes in the total export in the 10 minutes interval of these experiments. Further information on these observations drawn from short-term experiments required data which could be obtained only by extending the duration of the experiments. Logarithmic gradients of translocated radioactivity in stems have been noted by others (1, 9, 10) and attempts have been made to interpret them in relation to velocity or rate of translocation or to concurrent losses from the sieve tubes to the surrounding tissues (1, 2, 3, 4). In all cases but one (9), these gradients have been observed in short-term experiments. Only 2 reports (1, 10) have noted the changes in gradient characteristics that occur when the duration of C14-assimilation and translocation is increased, and in these the experiments were limited to periods from 5 to 30 minutes. Kursanov and Pristupa (5, 6, 8) have recently reported evidence in support of the classical concept of a circulation of carbon compounds from the leaves to the roots and back to the tops with metabolism in the roots playing an important role in the overall process. They have found that bean, pumpkin, and maize translocate mainly sucrose from the leaves to the roots. There it is metabolized to organic acids and amino acids in varying degree, (depending on the status of the mineral nutrition) and these acids are then translocated to the tops in the xylem sap. If such a criculation exists in the soybean, it was reasoned that, with increasing translocation time, the initial logarithmic decrease in C14 concentration with distance down the stem could change to an increasing gradient. This alteration might result from the combined effects of the decrease in export from the leaf and the increase in return flow from the root. The influence of increasing time on the translocation of the products of photosynthesis wvas, therefore, followed in young soybean plants maintained under defined conditions for intervals of 20 minutes to 70 hours after C1402 was assimilated for 10 minutes by one of the primary leaves. At each time interval the total amount of C14 exported by the leaf, its distribution within the plant and the identity of the labeled compounds were determined. The results of these experiments are interpreted in terms of the significance of the C14-concentration gradients in the stem as a measure of the rate of downward translocation and as an indicator for return flow from the root.
Infants use different mechanisms to make small and large number ordinal judgments

Previous research has shown indirectly that infants may use two different mechanisms--an object tracking system and an analog magnitude mechanism--to represent small (<4) and large (≥4) numbers of objects, respectively. The current study directly tested this hypothesis in an ordinal choice task by presenting 10- to 12-month-olds with a choice between different numbers of hidden food items. Infants reliably chose the larger amount when choosing between two exclusively small (1 vs. 2) or large (4 vs. 8) sets, but they performed at chance when one set was small and the other was large (2 vs. 4) even when the ratio between the sets was very favorable (2 vs. 8). The current findings support the two-mechanism hypothesis and, furthermore, suggest that the representations from the object tracking system and the analog magnitude mechanism are incommensurable.
Concordance of commercial data sources for neighborhood-effects studies.

Growing evidence supports a relationship between neighborhood-level characteristics and important health outcomes. One source of neighborhood data includes commercial databases integrated with geographic information systems to measure availability of certain types of businesses or destinations that may have either favorable or adverse effects on health outcomes; however, the quality of these data sources is generally unknown. This study assessed the concordance of two commercial databases for ascertaining the presence, locations, and characteristics of businesses. Businesses in the St. Louis, Missouri area were selected based on their four-digit Standard Industrial Classification (SIC) codes and classified into 14 business categories. Business listings in the two commercial databases were matched by standardized business name within specified distances. Concordance and coverage measures were calculated using capture–recapture methods for all businesses and by business type, with further stratification by census-tract-level population density, percent below poverty, and racial composition. For matched listings, distance between listings and agreement in four-digit SIC code, sales volume, and employee size were calculated. Overall, the percent agreement was 32% between the databases. Concordance and coverage estimates were lowest for health-care facilities and leisure/entertainment businesses; highest for popular walking destinations, eating places, and alcohol/tobacco establishments; and varied somewhat by population density. The mean distance (SD) between matched listings was 108.2 (179.0) m with varying levels of agreement in four-digit SIC (percent agreement = 84.6%), employee size (weighted kappa = 0.63), and sales volume (weighted kappa = 0.04). Researchers should cautiously interpret findings when using these commercial databases to yield measures of the neighborhood environment.
Social Involvement as a Mediator of Disaster-Induced Stress1

This study examined individuals either personally or indirectly exposed to disaster and hypothesized that social involvement would differentially mediate the effect of exposure on the mental health of male and female victims. The study reinterviewed individuals previously interviewed just prior to disastrous floods and the discovery of unsafe levels of dioxin. Results indicated that males and females differ in their response to disaster exposure. Males showed increased symptoms of alcohol abuse and depression as a result of either personal, or both personal and indirect, exposure to disaster. In contrast, females' s]ymptomatology was not directly elevated by personal disaster exposure. Both sexes were sensitive to demands for support as a mediator of disaster effects. That is, victims both personally exposed to disaster and heavily relied upon by network members were far more likely to somatize (females) or abuse alcohol (males) than personally exposed individuals subject to more moderate network demands. Although excellent spouse support attenuated male symptomatology, its presence was associated with an exacerbation of symptoms in personally exposed females. Results suggest the importance of considering both the positive and negative consequences of social involvement because, for women in particular, very strong social ties may be more burdensome than supportive in times of extreme stress.
Unique Matrix Structure in the Rough Endoplasmic Reticulum Cisternae of Pseudoachondroplasia Chondrocytes

Mutations in cartilage oligomeric matrix protein (COMP) cause two skeletal dysplasias, pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED/EDM1). Because COMP exists as a homopentamer, only one mutant COMP subunit may result in an abnormal complex that is accumulated in expanded rough endoplasmic reticulum (rER) cisternae, a hallmark of PSACH. Type IX collagen and matrilin-3 (MATN3), also accumulate in the rER cisternae of PSACH chondrocytes, but it is unknown how mutant COMP interacts with these proteins. The studies herein focus on defining the organization of these intracellularly retained proteins using fluorescence deconvolution microscopy. A unique matrix organization was identified in which type II procollagen formed a central core surrounded by a protein network of mutant COMP, type IX collagen, and MATN3. This pattern of matrix organization was found in multiple cisternae from single chondrocytes and in chondrocytes with different COMP mutations, indicating a common pattern of interaction. This suggests that stalling of mutant COMP and an interaction between mutant COMP and type II procollagen are initiating events in the assembly of matrix in the rER, possibly explaining why the material is not readily cleared from the rER. Altogether, these data suggest that mutant COMP initiates and perhaps catalyzes premature intracellular matrix assembly.
The ATP dependence of the incision and resynthesis steps of excision repair.

Abstract Escherichia coli made permeable by treatment with toluene can perform a mode of DNA synthesis that is stimulated by ultraviolet radiation and closely resembles the resynthesis step of excision repair. If ultraviolet-irradiated toluene-treated cells are incubated in an assay mixture with ATP but without the four deoxyribonucleoside triphosphates (dNTPs) or NAD, accumulations of single-strand breaks in the DNA are detected by alkaline sucrose gradient analysis. A second incubation with the dNTPs and NAD but without ATP produces nonconservative DNA synthesis in strains with normal levels of DNA polymerase I. However, in polA strains, ATP must be present during the second incubation in order to produce measurable amounts of ultraviolet-stimulated DNA synthesis. These results suggest that in strains deficient in DNA polymerase I there may be two ATP-dependent steps in this repair pathway, one required for incision and one associated with resynthesis.
α-Alkyl-α-aminosilanes. 1. Metalation and alkylation between silicon and nitrogen

Abstract tert-Butyl carbamate derivatives of readily available aminomethyltrialkylsilanes have been studied for their ability to undergo metalation between nitrogen and silicon, followed by reaction with an electrophile. Metalation is rapid and reaction with a variety of electrophiles proceeds efficiently. When a benzyl group is attached to nitrogen, benzylic deprotonation competes with deprotonation next to silicon. Metalation of tert-butyl carbamate derivatives of aminomethyltrimethylsilane can be used to prepare α-functionalized α-amino silanes. Download : Download full-size image
The accumulative pathway of vitellogenin in the mosquito oocyte: a high-resolution immuno- and cytochemical study

The accumulative pathway of yolk protein precursor, vitellogenin (VG), in the mosquito oocyte was studied by qualitative and quantitative VG immunolocalization, fixation with tannic acid, and lysosomal enzyme cytochemistry. VG binds to its receptors located on specific membrane microdomains at the base of and between the oocyte microvilli. The VG-receptor complexes then concentrate in coated pits and are internalized by coated vesicles. Dissociation of VG from its receptor occurs soon after transformation of coated vesicles into uncoated vesicular or tubular endosomes. The endosomes then coalesce into transitional yolk bodies (TYB), where VG accumulates and condenses. Narrow tubules without VG, connected to TYB, presumably represent a specific compartment for the recycling of VG receptors. TYB remain a “sink” for incoming VG until their transformation into mature yolk bodies (MYB), whereupon VG is transformed into a crystalline form, presumably vitellin. All compartments of the VG-accumulative pathway lack lysosomal enzymes and, therefore, the final VG destination, the MYB, is also endosomal and prelysosomal compartment, specialized for long-term storage of yolk protein.
Cyclic platelet-activating factor analogues derived from 2-deoxy-d-erythro-pentose

Abstract A method for the synthesis of chiral cyclic analogues of platelet-activating factor (PAF) is reported. Treatment of suitably substituted derivatives of 2-deoxy- d - erythro -pentose with phosphorus oxychloride, followed by choline p -toluenesulfonate generates cyclic phospholipids in good yield. Further chemical modification produces other compounds including optically active γ-butyrolactones such as 2-deoxy-5- O -hexadecyl-3- O -phosphocholyl- d - erythro -pentono-1,4-lactone and 2-deoxy-3- O -hexadecyl-5- O -phosphocholyl- d - erythro -pentono-1,4-lactone. All phospholipids were poor antagonists of PAF-induced aggregation of human platelets, and two analogs were poor agonists. The chemistry presented should be useful for the syntheses of other conformationally restricted analogues of PAF.
Activation of peroxisome proliferator-activated receptor γ inhibits osteoprotegerin gene expression in human aortic smooth muscle cells

Increasing evidence indicates an important role of PPAR gamma activation in modulating the development and progression of atherosclerosis, however, the mechanisms involved in these effects are not well understood since the PPAR gamma-regulated genes in vascular smooth muscle cells (VSMC) are poorly defined. Here we reported that PPAR gamma ligands, GW7845, ciglitazone and troglitazone had the effect of inhibiting osteoprotegerin (OPG) expression in human aortic smooth muscle cells (HASMC). The effect of GW7845 and ciglitazone on OPG expression was completely abolished by GW9662, a PPAR gamma antagonist. Overexpression of PPAR gamma in HASMC by the infection of a PPAR gamma adenovirus dramatically decreased OPG expression. In addition, PPAR gamma activation inhibited OPG promoter activity. Taken together, our data suggest that OPG expression is a novel PPAR gamma target gene in VSMC and downregulation of OPG expression by PPAR gamma activation provides a new insight into the understanding of the role of PPAR gamma in atheroscelrosis and hypertension.
Receptor-regulated Dynamic S-Nitrosylation of Endothelial Nitric-oxide Synthase in Vascular Endothelial Cells

The endothelial isoform of nitric-oxide synthase (eNOS) is regulated by a complex pattern of post-translational modifications. In these studies, we show that eNOS is dynamically regulated by S-nitrosylation, the covalent adduction of nitric oxide (NO)-derived nitrosyl groups to the cysteine thiols of proteins. We report that eNOS is tonically S-nitrosylated in resting bovine aortic endothelial cells and that the enzyme undergoes rapid transient denitrosylation after addition of the eNOS agonist, vascular endothelial growth factor. eNOS is thereafter progressively renitrosylated to basal levels. The receptor-mediated decrease in eNOS S-nitrosylation is inversely related to enzyme phosphorylation at Ser1179, a site associated with eNOS activation. We also document that targeting of eNOS to the cell membrane is required for eNOS S-nitrosylation. Acylation-deficient mutant eNOS, which is targeted to the cytosol, does not undergo S-nitrosylation. Using purified eNOS, we show that eNOS S-nitrosylation by exogenous NO donors inhibits enzyme activity and that eNOS inhibition is reversed by denitrosylation. We determine that the cysteines of the zinc-tetrathiolate that comprise the eNOS dimer interface are the targets of S-nitrosylation. Mutation of the zinc-tetrathiolate cysteines eliminates eNOS S-nitrosylation but does not eliminate NO synthase activity, arguing strongly that disruption of the zinc-tetrathiolate does not necessarily lead to eNOS monomerization in vivo. Taken together, these studies suggest that eNOS S-nitrosylation may represent an important mechanism for regulation of NO signaling pathways in the vascular wall.
La trilogía futurista de Oliverio Coelho: una mirada al sesgo de las crisis argentinas

Uno de los fenomenos mas signifi cativos en la narrativa argentina a partir de la dictadura militar de 1976-83 fue la alusion velada a la realidad a traves de desplazamientos narrativo-temporales. A fi nes de los setenta y durante los ochenta, muchos autores recurrieron a la novela neo-historica, primero por la censura pero mas tarde porque se sentian incapaces de representar el terrorismo de Estado y la desaparicion de miles de personas con las herramientas tradicionales de la literatura mimetico-realista, prefi riendo en cambio aludir a lo sucedido a traves de historias ambientadas en los origenes decimononicos de la nacion. Luego, con la instauracion de la economia neoliberal de mercado bajo la presidencia de Carlos Menem (1989-99), se produjo un desplazamiento temporal inverso y a veces se relato la nueva crisis –el achicamiento del Estado de bienestar, la destruccion de la industria nacional y el empobrecimiento generalizado– por medio de novelas de anticipacion y de ciencia fi ccion que traspolaban esas problematicas a imaginarios futuros distopicos.2 En ambos casos, ya sea que el desplazamiento cronologico fuera hacia el pasado o hacia el porvenir, se trataba de iluminar el presente a traves de historias veladas, oblicuas y por sobre todo alegoricas que aludian a otras epocas ante la imposibilidad de dar cuenta narrativa de lo real. Oliverio Coelho, un joven autor nacido en 1977, profundiza en esta estrategia al aludir cifradamente a las sucesivas crisis nacionales en una trilogia de novelas futuristas: Los invertebrables (2003), Borneo (2004) y Promesas naturales (2006). Coelho posee una prosa inedita hecha de palabras y sentidos levemente desfasados que producen una sensacion de extranamiento –“arsenal lexico infrecuente” y “lengua original” segun la resena de Manso (4)– y obliga a preguntarse sobre el genero o generos a que se podrian adscribir sus textos. Algunos adjetivos que vienen a la mente ante ciertos parrafos suyos
Extra-maze pre-exposure and choice behavior

Sixty albino rats were given a single test trial in a black-white T-maze following exposure to either a black or a white stimulus. It was found that a significant number of animals chose the non-exposed brightness in the maze. This is the first study to demonstrate that exposure to a stimulus outside the choice apparatus affects the choice behavior. Exposure time was not a significant factor in determining the animal’s choice but this may well have been the result of using long exposure times. A marked brightness preference was also noted.
Psoralen plus ultraviolet A does not increase the risk of cataracts: A 25-year prospective study

Background In some animal species, exposure of the unprotected eye to psoralen plus ultraviolet A (PUVA) therapy induces lens opacities. The relevance of these animal findings to human beings is not established. However, some case reports suggest that PUVA in human beings may increase the risk of lens abnormalities. Objective Our aim was to evaluate any possible associations between exposure to PUVA and increased risk of ocular lens abnormalities. Methods Since 1977 the PUVA follow-up study has periodically monitored the ocular status of 1237 cohort members with psoriasis using structured eye examinations. In our previous report we presented data results of the first 10 years of prospective study. This report includes data from two additional cycles of eye examinations that span an additional 14 years of follow-up. Results Based on our data from the last pre-1993 to final eye examination (2004), compared with that observed for the earlier period (first ever to last pre-1993 eye examination), the age-adjusted incidence of cataract did not increase significantly (incidence rate ratio=1.04, 95% confidence interval=0.82-1.31). In both the univariate and multivariate analyses increasing exposure to PUVA was not associated with a higher risk of cataract. Limitations Our cohort principally enrolled middle-aged or older patients so our data do not permit us to assess the effects of PUVA on the eyes of younger persons. Conclusions Increasing exposure to PUVA does not increase cataract risk among persons using eye protection at the rates used in our cohort.
The 108M polymorph of human catechol O-methyltransferase is prone to deformation at physiological temperatures.

The human gene for catechol O-methyltransferase (COMT) contains a common polymorphism that results in substitution of methionine (M) for valine (V) at residue 108 of the soluble form of the protein. While the two proteins have similar kinetic properties, 108M COMT loses activity more rapidly than 108V COMT at 37 °C. The cosubstrate S-adenosylmethionine (SAM) stabilizes the activity of 108M COMT at 40 °C. The 108M allele has been associated with increased risk for breast cancer, obsessive-compulsive disorder, and aggressive and highly antisocial manifestations of schizophrenia. In the current work, we have constructed homology models for both human COMT polymorphs and performed molecular dynamics simulations of these models at 25, 37, and 50 °C to explore the structural consequences of the 108V/M polymorphism. The simulations indicated that replacing valine with the larger methionine residue led to greater solvent exposure of residue 108 and heightened packing interactions between M108 and helices α2, α4 (...
Being business-like while pursuing a social mission: Acknowledging the inherent tensions in US nonprofit organizing

Nonprofit organizations face an increasing expectation to be more business-like. Although scholars have theoretically explored this phenomenon and studied its influence in various contexts, there has been little empirical examination of the ways in which nonprofit practitioners themselves describe and make sense of their organizations and their work as business-like. Specifically, scholars have not explored the ways in which nonprofit practitioners communicatively reconcile the inherent tensions between being business-like and the pursuit of a social mission. Based on findings from an eight-month ethnographic field study of a US nonprofit organization, this article describes the sophisticated ways in which nonprofit practitioners understand, define and negotiate the need to be business-like within the nonprofit context and the central role of communication in that process. Additionally, critical assessment of these findings reveals the political qualities of talking about nonprofit organizing as being business-like, leading to potential transformative redefinitions of the business-like imperative that acknowledge rather than suppress conflicts inherent in the practice of nonprofit organizing.
Mammalian frontal diploic vein and the human foramen caecum

The course of the frontal diploic vein in the mole Talpa and the tree shrew Tupaia is described and compared to the frontal diploic vein of other mam- mals. The frontal diploic vein in Talpa and Tupaia connects the dorsal sagittal sinus to the veins of the orbit and has an emissary function. In certain other mammals it has a diploic function and may drain towards the orbit (e.g., Orycteropus) or towards the dorsal sagittal sinus (e.g., Didelphis). The frontal diploic vein of these mammals is not homologous to the vein of the human foramen caecum, but to the human frontal diploic vein. The vein of the foramen caecum is a problematic structure: its incidence in embryos and children is not clear. It is generally accepted that the mammalian venous system is more variable than the arterial or nervous systems. As a result little attention is paid to the venous system in comparative anatomical studies, and veins and associated structures are often misidentified or com- pletely ignored. Comparative anatomical research shows that certain parts of the venous system are very con- stant within taxa, while interesting variations exist among taxa. In this paper the frontal diploic vein of mammals will be discussed as an example of such a structure. Its course and function in moles and tree shrews will be described, and inferences will be made about its function in these and other mammals. The proposed homology between the frontal diploic vein and the vein of the human foramen caecum will also be discussed. The best published account of the frontal diploic vein in mammals is that of Miller's anatomy of the dog (Ev- ans and Christensen, 1979). In the dog, the frontal di- ploic vein is small and appears in the orbit by means of a foramen in the postorbital process. It drains the frontal sinus and frontal diploe, and is usually connected to the dorsal sagittal sinus, but in some dogs this part of the vein is absent. The frontal diploic vein is small or absent in many mammals. It is sometimes a large structure, but is usually ignored in spite of its size even in those species. Clark (1926) noticed the presence of the "venous foramen" for the frontal diploic vein in the orbit of the tree shrew Ptilocercus, but gives no details, whereas later workers on tree shrews, such as Muller (1935) and Saban (1956-1957) do not discuss the structure at all. MATERIALS AND METHODS
Melanoma-Derived Interleukin 6 Inhibits In Vivo Melanoma Growth

Malignant melanomas are capable of producing a wide range of cytokines with multiple biologic functions, including interleukin 6 (IL-6). We have observed an inverse relationship between IL-6 production of three B16-derived murine melanoma cell lines (NP133, HFH18, and HFH(M)) and the tumorigenicity of these melanoma cells in syngeneic mice. To further test the effect of IL-6 on melanoma growth, a non-IL-6-producing murine B16-derived melanoma cell line (HFH18) was transfected with a murine IL-6 expression vector, resulting in stable transfectants (HFH18/IL-6(+)) that expressed significant amounts of IL-6 mRNA and secreted high levels of bioactive IL-6. Syngeneic C57BL/6 mice inoculated subcutaneously with HFH18/IL-6(+) cells developed tumors that reached a final mean diameter of less than half the size of tumors that developed in mice inoculated with either HFH18 parental or HFH18 cells transfected with the IL-6 cDNA in the non-coding 3'-5' orientation (HFH18/IL-6(-) cells). In addition, mice bearing IL-6-producing HFH18/IL-6(+) tumors survived twice as long as mice bearing HFH18 parental or HFH18/IL-6(-) tumors. The specificity of melanoma growth inhibition by IL-6 was confirmed by the reversal of the slow-growing phenotype of HFH18/IL-6(+) cells by local peritumoral administration of neutralizing alpha-murine IL-6 antibody. IL-6-producing melanoma cells exerted a growth-inhibitory effect on distant parental tumors in a dose-dependent manner. The growth of HFH18/IL-6(+) melanomas was also decreased in nude mice, suggesting that melanoma-derived IL-6 may mediate this anti-tumor effect independently of a normal host B- and T-cell immune response. Thus, melanoma-derived IL-6 exerts a significant inhibitory effect on cutaneous melanoma growth and progression. These results indicate that melanoma cytokines may have a profound effect on tumor pathogenesis.
FACING SOCIETAL CHALLENGES: THE NEED FOR NEW PARADIGMS IN RURAL TRANSIT SERVICE

In response to major societal trends, rural transit operators should consider different ways to organize, design, and deliver public transit services. This article summarizes societal changes affecting rural areas and identifies five "new paradigms" in rural service organization and delivery operators to meet the needs created in many rural areas. The article concludes that many operators in a variety of rural settings could enhance their role and better meet the transportation challenge of a changing population by adopting different service paradigms.
The E1 ubiquitin-activating enzyme Uba1 in Drosophila controls apoptosis autonomously and tissue growth non-autonomously.

Ubiquitination is an essential process regulating turnover of proteins for basic cellular processes such as the cell cycle and cell death (apoptosis). Ubiquitination is initiated by ubiquitin-activating enzymes (E1), which activate and transfer ubiquitin to ubiquitin-conjugating enzymes (E2). Conjugation of target proteins with ubiquitin is then mediated by ubiquitin ligases (E3). Ubiquitination has been well characterized using mammalian cell lines and yeast genetics. However, the consequences of partial or complete loss of ubiquitin conjugation in a multi-cellular organism are not well understood. Here, we report the characterization of Uba1 , the only E1 in Drosophila . We found that weak and strong Uba1 alleles behave genetically differently with sometimes opposing phenotypes. Whereas weak Uba1 alleles protect cells from cell death, clones of strong Uba1 alleles are highly apoptotic. Strong Uba1 alleles cause cell cycle arrest which correlates with failure to reduce cyclin levels. Surprisingly, clones of strong Uba1 mutants stimulate neighboring wild-type tissue to undergo cell division in a non-autonomous manner giving rise to overgrowth phenotypes of the mosaic fly. We demonstrate that the non-autonomous overgrowth is caused by failure to downregulate Notch signaling in Uba1 mutant clones. In summary, the phenotypic analysis of Uba1 demonstrates that impaired ubiquitin conjugation has significant consequences for the organism, and may implicate Uba1 as a tumor suppressor gene.
A Conversation with Gerry Hahn

[This abstract is based on the author’s abstract.] An interview with distinguished statistician and author Gerald (Gerry) J. Hahn reveals the educational and professional background that led to his long association with the General Electric Company wher..
Epigenetics and human disease.

Altered IGF2 imprinting in somatic overgrowth provides further evidence for the involvement of epigenetics in human disease (pages 311–316).
Retention index calculation without n-alkanes—the virtual carbon number

For the fast gas chromatographic identification of separated components the retention index is still one of the most often used tools, although mass spectrometry is available in almost all analytical laboratories. For the calculation of the retention indices it is not necessary to use n-alkanes or any other homologous series. If the analyte contains some compounds, not necessarily belonging to a homologous series, with well-known retention indices those compounds can be used as index references and the index of the other compounds can be calculated as is done using n-alkanes. The only difference is that instead of the carbon number of the n-alkanes, virtual carbon numbers of the reference compounds should be used. The method of calculation, and the effect of this method of calculation on the reproducibility are discussed in this paper, and analyses of some halogenated compounds and marjoram oil are used as experimental examples.
Properties of and Proteins Associated with the Extracellular ATPase of Chicken Gizzard Smooth Muscle: A MONOCLONAL ANTIBODY STUDY

The chicken gizzard smooth muscle extracellular ATPase (ecto-ATPase) is a low abundance, high specific activity, divalent cation-dependent, nonspecific nucleotide triphosphatase (NTPase). The ATPase is a 66-kDa glycoprotein with a protein core of 53 kDa (Stout, J.G. and Kirley, T.L.(1994) J. Biochem. Biophys. Methods 29, 61-75). In this study we evaluated the characteristics of a bank of monoclonal antibodies raised against a partially purified chicken gizzard ecto-ATPase. 18 monoclonal antibodies identified by an ATPase capture assay were tested for effects on ATPase activity as well as for their Western blot and immunoprecipitation potential. The five most promising monoclonal antibodies were used to immunopurify the ecto-ATPase. The one-step immunoaffinity purification of solubilized chicken gizzard membranes with all five of these monoclonal antibodies isolated a 66-kDa protein whose identity was confirmed by N-terminal sequence analysis to be the ecto-ATPase. Several of these monoclonal antibodies stimulated ecto-ATPase activity similar to that observed previously with lectins. Western blot analysis revealed that three of the five monoclonal antibodies recognized a major immunoreactive band at 66 kDa (53-kDa core protein), consistent with previous purification results. The other two antibodies recognized proteins of approximately 90 and 160 kDa on Western blots. The 90-kDa co-immunopurifying (and presumably associated or related) protein was identified by N-terminal analysis as LEP100, a glycoprotein that shuttles between the plasma and lysosomal membranes. The approximately 160-kDa co-immunopurifying protein was identified by N-terminal analysis as integrin, a protein involved in extracellular contacts with adhesion molecules. Extended N-terminal sequence analysis of the immunopurified 66-kDa ecto-ATPase revealed some sequence homology with mouse lysosomal associated membrane protein. Tissue distribution of the ecto-ATPase showed that the highest levels of protein were expressed in muscle tissues (cardiac, skeletal, and smooth) and brain.
A Low Cost Attitude and Heading Reference System Based on a MEMS IMU for a T-Quadrotor

Combining signals from accelerometers and gyroscopes is a widely used way to estimate robot attitude. However, when using a Kalman filter in this case, the measurements are vulnerable to dynamic accelerations which will result in substantial attitude estimation errors. The attitude acquisition method presented in this paper takes an attitude quaternion as system measurements and uses a Kalman filter to fuse signals from MEMS gyroscopes, accelerometers and magnetic sensors. In order to remove the influence of dynamic accelerations, when dynamic accelerations are found to be significant, a Quaternion-based Strapdown Navigation System (Q-SINS) algorithm is only applied without the Kalman filtering. When the dynamic accelerations are not significant, both the Q-SINS and the Bi-vector algorithms are utilized and fused using the Kalman filter for improved system performance. Compared with some other highly nonlinear and complicated attitude algorithms, the Attitude and Heading Reference System (AHRS) proposed in this paper is computationally less expensive and more suitable for real-time applications.Copyright © 2011 by ASME
Power series solutions

A means of extending the radius of convergence of a power series solution of a system of differential equations is presented. It is essentially a change of the independent variable by means of a conformal mapping. Conditions on this change of variables which should yield a computational advantage are discussed.
Self-concepts of institutional and non-institutional educable mentally retarded children.

20 public school special education and 20 institutionalized educable mentally retarded children were compared on an experimental I Feel—Me Feel self-perception scale. No significant differences in ...