Miracle-dz/UniFAR-FTUs huggingface dataset:
A study of intercellular bridges during spermatogenesis in the rat.

A morphological evaluation of intercellular bridges was undertaken during rat spermatogenesis. The dimensions and relationships of the bridges were shown to vary during different phases of spermatogenesis. Cellular divisions of spermatogonia and spermatocytes resulted in the partitioning of pre-existing bridges by complex structures termed bridge partitioning complexes, which are described in detail, as is the process whereby new bridges are formed. The structure of premeiotic bridges was generally consistent; however, during spermiogenesis, the structure of bridges and bridge contents were modified at specific phases of their development. The plasma membrane density associated with the cytoplasmic aspect of early step 1 spermatids separated into multiple dense bands that encircled the peripheral aspect of late step 1 spermatid bridges. By step 2 of spermiogenesis, these dense bands became associated with several cisternae of endoplasmic reticulum, which later coalesced into a single saccule that completely encircled the bridge structure by step 4. At steps 10-13 of spermiogenesis, the single saccule of endoplasmic reticulum vesiculated into many smaller cisternae. Also, filament-bounded densities (measuring 10-12 nm in diameter) appeared within the bridge channel. At step 17 of spermiogenesis, the filament-bounded densities were no longer apparent, but an anastomosing network of endoplasmic reticulum, often in the configuration of a sphere, occupied the entire central region of the bridge. In step 19 spermatids, the smooth endoplasmic reticulum within the bridge channel and the multiple cisternae lining the bridge density were gradually displaced. The subsurface density of bridges gradually lost its prominence. Some cytoplasmic lobes were connected by extremely narrow (approximately 22 nm) cytoplasmic channels. Similar-appearing channels were seen on the surface zone of cytoplasmic lobes or residual bodies, this observation suggesting that channels were sites of severence of bridges. Just prior to the separation or disengagement of the spermatid from the cytoplasmic lobe, selected bridges appeared to open to form large masses. After spermiation, residual bodies were not found joined by bridges; but from the size of some of the residual bodies, it was suspected that they were formed by coalescence of more than one cytoplasmic lobe. Freeze-fracture demonstrated few intramembranous particles on either the P or E face of the plasma membrane forming the bridge; this finding suggested bridge structures restricted free lateral movement of membrane constituents across the bridge. (ABSTRACT TRUNCATED AT 400 WORDS)
Referring under Restricted Interactivity Conditions

We report results on how the collaborative process of referring in task-oriented dialogue is aected by the restrictive interactivity of a turn-taking policy commonly used in dialogue systems, namely push-to-talk. Our findings show that the restriction did not have a negative effect. Instead, the stricter control imposed at the interaction level favoured longer, more eective referring expressions, and induced a stricter and more structured performance at the level of the task.
Effects of abciximab, ticlopidine, and combined Abciximab/Ticlopidine therapy on platelet and leukocyte function in patients undergoing coronary angioplasty.

BACKGROUND Abciximab and ticlopidine reduce adverse cardiovascular events after percutaneous transluminal coronary angioplasty (PTCA). The goal of the current study was to determine if combined abciximab/ticlopidine therapy inhibits arterial thrombosis more effectively than either treatment alone. The effect of each therapy on platelet-leukocyte interactions was also investigated. METHODS AND RESULTS Whole blood samples from 14 patients undergoing PTCA who received abciximab therapy, ticlopidine therapy, or both treatments were evaluated using dynamic experimental systems. Mural thrombus formation under arterial shear conditions (1500 s(-1)) was determined in a parallel plate flow chamber. Shear-induced platelet aggregation was evaluated using a cone-and-plate viscometer at a shear rate of 3000 s(-1). Of the 3 treatments, combined abciximab/ticlopidine therapy produced the most consistent reduction in shear-induced platelet aggregation and the most prolonged inhibition of mural thrombosis. Three days after PTCA, abciximab/ticlopidine treatment decreased mural thrombus formation to approximately 50% of baseline values. Abciximab treatment alone inhibited mural thrombosis for only 1 day after PTCA, whereas ticlopidine treatment alone had no significant effect. Two hours after PTCA, abciximab therapy significantly decreased the number of circulating platelet-neutrophil aggregates but significantly enhanced P-selectin-mediated leukocyte adhesion on the collagen/von Willebrand factor-platelet surface. CONCLUSIONS Combined therapy with abciximab and ticlopidine has a prolonged inhibitory effect on mural thrombosis formation relative to either treatment alone. Further, we demonstrated an unexpected effect of abciximab in enhancing P-selectin-mediated leukocyte adhesion.
Safety of pramipexole in patients with restless legs syndrome

In 1999, falling asleep at the wheel was reported as a new and worrisome side effect in eight patients with PD treated with nonergot dopamine agonists (DA). Five of these patients reported sudden unexpected “sleep attacks” without preceding fatigue.1 Subsequently, more patients who were treated with DA (including ergot DA) for PD have been reported to have similar sleep attacks.2 Because the nonergot DA pramipexole is successfully used in the treatment of restless legs syndrome (RLS),3 we investigated its safety with particular regard to sleep attacks in patients with RLS. We surveyed all patients in our outpatient clinic who have been treated with pramipexole to control RLS symptoms by a mailed questionnaire. Patients were asked about side effects of pramipexole, occurrence and degree of daytime fatigue, occurrence of unexpected dozing off (sleep attacks), dozing off due to tiredness (sleep episodes) and its relationship to drug intake, and intake of other drugs. …
Predictors of Outcome in Traumatic Brain Injury: New Insight Using Receiver Operating Curve Indices and Bayesian Network Analysis

Background Traumatic brain injury remains a global health problem. Understanding the relative importance of outcome predictors helps optimize our treatment strategies by informing assessment protocols, clinical decisions and trial designs. In this study we establish importance ranking for outcome predictors based on receiver operating indices to identify key predictors of outcome and create simple predictive models. We then explore the associations between key outcome predictors using Bayesian networks to gain further insight into predictor importance. Methods We analyzed the corticosteroid randomization after significant head injury (CRASH) trial database of 10008 patients and included patients for whom demographics, injury characteristics, computer tomography (CT) findings and Glasgow Outcome Scale (GCS) were recorded (total of 13 predictors, which would be available to clinicians within a few hours following the injury in 6945 patients). Predictions of clinical outcome (death or severe disability at 6 months) were performed using logistic regression models with 5-fold cross validation. Predictive performance was measured using standardized partial area (pAUC) under the receiver operating curve (ROC) and we used Delong test for comparisons. Variable importance ranking was based on pAUC targeted at specificity (pAUCSP) and sensitivity (pAUCSE) intervals of 90–100%. Probabilistic associations were depicted using Bayesian networks. Results Complete AUC analysis showed very good predictive power (AUC = 0.8237, 95% CI: 0.8138–0.8336) for the complete model. Specificity focused importance ranking highlighted age, pupillary, motor responses, obliteration of basal cisterns/3rd ventricle and midline shift. Interestingly when targeting model sensitivity, the highest-ranking variables were age, severe extracranial injury, verbal response, hematoma on CT and motor response. Simplified models, which included only these key predictors, had similar performance (pAUCSP = 0.6523, 95% CI: 0.6402–0.6641 and pAUCSE = 0.6332, 95% CI: 0.62–0.6477) compared to the complete models (pAUCSP = 0.6664, 95% CI: 0.6543–0.679, pAUCSE = 0.6436, 95% CI: 0.6289–0.6585, de Long p value 0.1165 and 0.3448 respectively). Bayesian networks showed the predictors that did not feature in the simplified models were associated with those that did. Conclusion We demonstrate that importance based variable selection allows simplified predictive models to be created while maintaining prediction accuracy. Variable selection targeting specificity confirmed key components of clinical assessment in TBI whereas sensitivity based ranking suggested extracranial injury as one of the important predictors. These results help refine our approach to head injury assessment, decision-making and outcome prediction targeted at model sensitivity and specificity. Bayesian networks proved to be a comprehensive tool for depicting probabilistic associations for key predictors giving insight into why the simplified model has maintained accuracy.
XMM-Newton Detection of a Compton-thick AGN in the 1 Jy ULIRG/LINER F04103–2838

We report on the detection of Fe Kα emission in F04103–2838, an ultraluminous infrared galaxy [ULIRG; log (LIR/L☉) ⩾ 12] optically classified as a LINER. Previous Chandra observations suggested the presence of both a starburst and an active galactic nucleus (AGN) in this source. A deeper (~20 ks) XMM-Newton spectrum reveals an Fe Kα line at rest-frame energy ~6.4 keV, which is consistent with cold neutral iron. The best-fit spectral model indicates that the Fe Kα line has an equivalent width of ~1.6 keV. The hard X-ray emission is dominated by a Compton-thick AGN with an intrinsic 0.2-10 keV luminosity of ~1044 ergs s−1, while the soft X-ray emission is from ~0.1 keV gas attributed to the starburst. The X-ray spectrum of this source bears a striking resemblance to that of the archetypal luminous infrared galaxy NGC 6240, despite differences in merger state and infrared properties.
Rethinking the Fifth Discipline: Learning Within the Unknowable

Systematic thinking, not reductionism issues and dilemmas, not problems balancing confusion with clarity debating boundaries, clients, issues and dilemmas deepening systematic appreciation exploring purpose(s) and action systems of processes systems of structure systems of meaning systems of knowledge-power systematic management systematic measurement balancing instrumentalism with experience teaching and learning systematic management.
Student satisfaction or happiness? : a preliminary rethink of what is important in the student experience

Purpose – This paper aims to investigate the purpose of the complex open system of higher education and to explore this transformative experience as personal flourishing, where students come to terms with a way of being, matching their potentiality with their agency and leading to profound happiness. There is influential, but not uncontested (Tsinidou et al., 2010), literature concerning higher education institutes as education service providers, functioning like any other business (DeShields, 2005). Eagle and Brennan (2007, p. 4) argue that academic staff as service providers are thus vital to process delivery. Using a service model and traditional corporate quality frameworks, there is a temptation to measure how a service ethos serves recipients and co-producers – students, donor, industry and sponsors – negating education’s transformative and uncertain nature, rather than taking the externality of process delivery as a guide. Design/methodology/approach – The research is based on a questionnaire desig.
Workplace fairness and emotional exhaustion in Nigeria police: The moderating role of gender

Abstract This study examined the moderating role of gender in the relationship between perceived workplace fairness and reported level of emotional exhaustion among a sample of Nigeria police. A total of 214 participants took part in the cross-sectional survey. Results of the moderated hierarchical regression analysis provided support for gender as a moderating variable in the relationship between perceived workplace fairness and emotional exhaustion, such that perceived workplace fairness was a stronger predictor of emotional exhaustion among male police than for female police. The practical implications for the management of emotional exhaustion in general, and for the Nigeria police in particular, were emphasized.
Teaching to Convince, Teaching to Empower: Reflections on Student Resistance and Self-Defeat at Predominantly White vs. Racially Diverse Campuses

1024x768 A key challenge of teaching racism in the so-called “post-racial” era is to get students to realize that racism does in fact exist. When faced with these challenges, it is not uncommon for professors to dedicate much of their time convincing students of the significance and persistence of racism. This is especially true when teaching at predominantly “white” institutions, where students likely do not navigate racism on an everyday basis. However, these methods may not be as effective when teaching racism at colleges, where the student body is predominantly of color, immigrant, and/or working class. Here, new challenges arise. One central challenge I have faced is teaching about the persistence of racism without disempowering students who do encounter racism in their everyday lives. In this paper, I reflect on these challenges and the strategies I developed to deal with student resistance at three different institutions. I also offer some suggestions on how our colleges and universities can create supportive environments for women and faculty of color who teach racism. This paper is intended for college faculty who teach a variety of courses in which racism is addressed centrally as well as for college administrators interested in retaining women and faculty of color. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:. 0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}
Boundedness and stability for nonautonomous bidirectional associative neural networks with delay

The paper studies the nonautonomous bidirectional associative neural networks systems with time-varying delays. By applying Lyapunov functional method, introducing many parameters, and combining this with the techniques of inequality analysis, a series of criteria of the uniform ultimate boundedness, global exponential stability, and the existence of periodic solutions are obtained. The results obtained in this paper are new and useful.
A complicated but symbiotic affair: The relationship between mainstream media and social media in the coverage of social protests in southern Africa

Abstract Debates on the relationship between mainstream and social media have sputtered on in the academy, especially during crisis situations and social protests. Mostly based on conjecture and anecdotal evidence, there is little theorisation on the relationship between the two mediums in different contexts. Far from being competitors, mainstream and social media have converged in complex ways to broaden the mediated public sphere in southern Africa. While social media were instrumental in breaking news during social protests, mainstream media weighed in with verification, contextualisation and amplification. The convergence between the two public spheres has necessitated the emergence of collaborative journalism practices, making heard the voices of previously silenced and delegitimised activists.
Cell dynamics and gene expression control in tissue homeostasis and development

During tissue and organ development and maintenance, the dynamic regulation of cellular proliferation and differentiation allows cells to build highly elaborate structures. The development of the vertebrate retina or the maintenance of adult intestinal crypts, for instance, involves the arrangement of newly created cells with different phenotypes, the proportions of which need to be tightly controlled. While some of the basic principles underlying these processes developing and maintaining these organs are known, much remains to be learnt from how cells encode the necessary information and use it to attain those complex but reproducible arrangements. Here, we review the current knowledge on the principles underlying cell population dynamics during tissue development and homeostasis. In particular, we discuss how stochastic fate assignment, cell division, feedback control and cellular transition states interact during organ and tissue development and maintenance in multicellular organisms. We propose a framework, involving the existence of a transition state in which cells are more susceptible to signals that can affect their gene expression state and influence their cell fate decisions. This framework, which also applies to systems much more amenable to quantitative analysis like differentiating embryonic stem cells, links gene expression programmes with cell population dynamics.
RAS genes and growth control in Saccharomyces cerevisiae

ras genes have been identified in such evolutionarily diverse organisms as mammals, insects, and fungi. Initial interest stemmed from the role of these genes in the etiology of mammalian cancers, but they'now appear to play central biological roles in other eucaryotes as well. Because genetic manipulations can be performed with relative ease in the yeast Saccharomyces cerevisiae, the most rapid advances in our knowledge of the RAS gene function come from studies of this organism. Studies of the RAS genes in S. cerevisiae have provided important information about the control of cell growth in yeasts, information which may be relevant to the function of the ras gene in mammalian cells as well. ras genes were originally identified as those responsible for the transforming ability of Harvey and Kirsten murine sarcoma viruses (reviewed in reference 12). These helper- dependent retroviruses induce tumors in mice after a short latent period, usually 2 to 3 weeks. The transforming genes present in the viruses code for similar 21,000-dalton proteins, termed p21. Independent experiments have revealed that human tumors contain DNA sequences capable of transforming mouse fibroblast NIH 3T3 cells. Cloning of these sequences has indicated that many are cellular homologs of the viral ras genes. Three distinct genes have been identified in this manner: two genes closely related to 31) and a third gene with
Sequential Effects in Two-Choice Reaction Time Tasks: Decomposition and Synthesis of Mechanisms

Abstract Performance on serial tasks is influenced by first- and higher-order sequential effects, respectively, due to the immediately previous and earlier trials. As response-to-stimulus interval (RSI) increases, the pattern of reaction times transits from a benefit-only mode, traditionally ascribed to automatic facilitation (AF), to a cost-benefit mode, due to strategic expectancy (SE). To illuminate the sources of such effects, we develop a connectionist network of two mutually inhibiting neural decision units subject to feedback from previous trials. A study of separate biasing mechanisms shows that residual decision unit activity can lead to only first-order AF, but higher-order AF can result from strategic priming mediated by conflict monitoring, which we instantiate in two distinct versions. A further mechanism mediates expectation-related biases that grow during RSI toward saturation levels determined by weighted repetition (or alternation) sequence lengths. Equipped with these mechanisms, the network, consistent with known neurophysiology, accounts for several sets of behavioral data over a wide range of RSIs. The results also suggest that practice speeds up all the mechanisms rather than adjusting their relative strengths.
Study of the Role of the Low-Affinity Neurotrophin Receptor p75 in Naturally Occurring Cell Death during Development of the Rat Retina

The aim of this study was to examine the tempo-spatial expression of low-affinity neurotrophin receptor p75, or p75NTR, and its role in the induction of retinal ganglion cell (RGC) apoptosis in the rat retina during development. The cellular distribution of p75 in the retina was demonstrated with immunohistochemistry and double-immunofluorescent staining. Apoptosis in the developing rat retina was detected by DNA gel electrophoresis, and the number of RGCs undergoing apoptosis was estimated by terminal deoxyribonucleotidyl-mediated dUTP-digoxigenin nick end labeling (TUNEL). To localize p75 on apoptotic RGCs, p75 immunofluorescence and TUNEL fluorescent staining was performed on sections with Fluoro-Gold-prelabeled RGCs. p75 immunoreactivities were not detected either on the RGCs or TUNEL-positive cells, whereas Müller cell processes were p75 immunopositive. Thus, it was most unlikely that p75 induced apoptosis of RGCs in the rat retina.
Febrile temperatures can synchronize the growth of Plasmodium falciparum in vitro

To investigate the possibility that the host fever response in malaria may affect parasite development, we studied the effect of temperature on Plasmodium falciparum in erythrocytic culture in vitro. Growth was markedly suppressed at 40 degrees C compared with 37 degrees C, due to disruption of the second half of the 48-h erythrocytic cycle. However, young intraerythrocytic parasites, which are highly exposed to fever during natural infection, appeared to develop normally at 40 degrees C. Because of the differential temperature sensitivity within the erythrocytic cycle, asynchronous cultures could be synchronized by transient elevations of temperature. Pronounced synchronization was observed when cultures were exposed to periodic elevations of temperature that simulated the 48-h fever cycle of tertian malaria. These findings indicate that malaria fever might act to promote parasite synchronization in vivo.