Physiology and Pharmacology Episcleral Venous Pressure and IOP Responses to Central Electrical Stimulation in the Rat

PURPOSE. Histological evidence suggests a role for the central nervous system in controlling episcleral venous pressure (EVP). Based on prior studies that identified candidate regions in the brain stem, the present study assessed the effect of electrical stimulation at the location of the superior salivatory nucleus (SSN) on EVP in rats. METHODS. Male Sprague-Dawley rats (n ¼ 11) were anesthetized using pentobarbital sodium (50 mg/kg intraperitoneally initially, supplemented intravenously [IV] as needed) and paralyzed with gallamine triethiodide (1 mg/kg, IV). The animals were artificially ventilated and the femoral artery and vein were cannulated for blood pressure measurement and drug administration. Carotid blood flow was measured with an ultrasound flow probe and heart rate with a cardiotachometer. IOP was measured through a cannula in the vitreous compartment and EVP was measured through a micropipette in episcleral veins using the servonull technique. After a craniotomy was performed, a unipolar stainless steel electrode was inserted into the brainstem at the coordinates of the SSN using a stereotactic instrument. Stimulations were performed at 20Hz, 9 lA, 1 ms pulse duration, and 200 pulses. RESULTS. Stimulation at the SSN coordinates increased IOP from 10.6 6 0.4 to 11.8 6 0.6 mm Hg (P < 0.01) and EVP from 7.8 6 1.3 to 10.7 6 1.1 mm Hg (P < 0.01). Mean arterial pressure, carotid blood flow, and heart rate remained unaltered. CONCLUSIONS. The present study indicates that the SSN may participate in regulating EVP. Keywords: episcleral venous pressure, superior salivatory nucleus, stimulation, IOP S teady-state IOP can be described by the Goldmann equation as the relationship between aqueous flow, uveoscleral outflow, outflow facility, and episcleral venous pressure (EVP). 1,2 EVP is the pressure that has to be overcome for fluid to leave the eye via the trabecular outflow pathway and, in humans under normal conditions, EVP accounts for roughly 60% of IOP. Despite its importance for IOP homeostasis, the physiology of the episcleral venous pressure is poorly understood. The current de facto standard for measuring EVP is the venomanometer described by Zeimer et al. 12 Recently, a study by Samuels et al. The brainstem, however, appears to be the first relay station for nerves supplying the eye, and, thus, the nuclei there are likely to be more specialized than higher-order centers in the diencephalon. METHODS The study was approved by the institutional animal care and use committee of the University of Texas Health Science Center at San Antonio and conducted in accordance with the ARVO guidelines for animal use in vision research. All animals were euthanized with an anesthetic overdose at the end of the experiment without regaining consciousness. Animal Preparation Male Sprague Dawley rats (n ¼ 11, 305.4 6 8.6 g) were anesthetized using pentobarbital sodium (Sigma-Aldrich, 50 mg/kg intraperitoneally, supplemented intravenously as needed). A tracheotomy was performed and the animal was respire

Measuring motivations of crowdworkers: The multidimensional crowdworker motivation scale

Crowd employment is a new form of short-term and flexible employment which has emerged during the past decade. In order to understand this new form of employment, it is crucial to illuminate the underlying motivations of the workforce involved in it. This paper introduces the Multidimensional Crowdworker Motivation Scale (MCMS), a scale for measuring the motivation of crowdworkers on micro-task platforms. The MCMS is theoretically grounded in self-determination theory and tailored specifically to the context of paid crowdsourced micro-labor. The scale measures the motivation of crowdworkers along six motivational dimensions, ranging from amotivation to intrinsic motivation. We validated the MCMS on data collected in ten countries and three income groups. Factor analyses demonstrated that the MCMS's six dimensions showed good model fit, validity, and reliability. Furthermore, our measurement invariance tests showed that motivations measured with the MCMS are comparable across countries and income groups, and we present a first cross-country comparison of crowdworker motivations. This work constitutes an important first step towards understanding the motivations of the international crowd workforce.Comment: 33 pages; added section; additional validation; corrected typo

Metabolic control of G1–S transition: cyclin E degradation by p53-induced activation of the ubiquitin–proteasome system

When mitochondrial function fails, p53 is recruited to get rid of cyclin E, bringing mitotic progression to a halt

Myopieprogressionshemmung Zusammenfassung der aktuellen Literatur

Hintergrund Kurzsichtigkeit kann zwar mit optischen Hilfsmitteln korrigiert werden, erhöht jedoch auch bei geringer Ausprägung das Risiko für eine Sehbehinderung durch andere Augenkrankheiten im späteren Lebensalter. Insbesondere hohe Myopie sollte vermieden werden. Ziel der gegenwärtigen Arbeit ist es, die rezente Literatur zum Thema Myopieprogressionshemmung zusammenzufassen.Material und Methode Es wurde eine Literatursuche mittels Medline/PubMed durchgeführt und die rezente Literatur zusammengefasst, wobei Metaanalysen und randomisiert kontrollierte Studien bevorzugt verwendet wurden, sofern verfügbar. Resultate Zeit im Freien, pharmakologische Therapie mit Atropin (oder ähnlichen Substanzen) sowie optische Methoden Bifokal/Gleitsichtbrille, Orthokeratologie, Multifokalkontaktlinsen sowie Kontaktlinsen mit hoher positiver sphärischer Aberration) sind wirksam zur Hemmung der Myopieprogression. Zeit im Freien ist zusätzlich wirksam in Bezug auf die Inzidenzhemmung. Unklar sind derzeit v. a. die optimale Dauer der Therapie sowie die Wirksamkeit in höheren Lebensjahren. Schlussfolgerung Zur Myopieprogressionshemmung stehen aktuell wirksame Therapien zur Verfügung und sollten im klinischen Alltag in Erwägung gezogen werden.(VLID)435235

Building connections: How scientists meet each other during a conference

We present the results of two studies on how individuals interact with each other during a international, interdisciplinary scientific conference. We first show that contact activity is highly variable across the two conferences and between different socio-demographic groups. However, we found one consistent phenomenon: Professors connect and interact significantly less than the other participants. We interpret this effect as non-tenured researchers using conferences to accumulate social capital, while established researchers already have such capital. We then show that groups mix well during conferences, but note that a language-based homophily is always present. Finally, we show that the dynamics of the contacts across days is also similar between conferences. First day connections are established, then filtering occurs during the following days. The connection turnover between consecutive days proves to be large (∼50 %), and related to the intensity of interactions

Building connections: How scientists meet each other during a conference

We present the results of two studies on how individuals interact with each other during a international, interdisciplinary scientific conference. We first show that contact activity is highly variable across the two conferences and between different socio-demographic groups. However, we found one consistent phenomenon: Professors connect and interact significantly less than the other participants. We interpret this effect as non-tenured researchers using conferences to accumulate social capital, while established researchers already have such capital. We then show that groups mix well during conferences, but note that a language-based homophily is always present. Finally, we show that the dynamics of the contacts across days is also similar between conferences. First day connections are established, then filtering occurs during the following days. The connection turnover between consecutive days proves to be large (∼50 %), and related to the intensity of interactions

AI Psychometrics: Assessing the psychological profiles of large language models through psychometric inventories

We illustrate how standard psychometric inventories originally designed for assessing non-cognitive human traits can be repurposed as diagnostic tools to evaluate analogous traits in large language models (LLMs). We start from the assumption that LLMs, inadvertently yet inevitably, acquire psychological traits (metaphorically speaking) from the vast text corpora on which they are trained. Such corpora contain sediments of the personalities, values, beliefs and biases of the countless human authors of these texts, which LLMs learn through a complex training process. The traits that LLMs acquire in such a way can potentially influence their behavior, i.e., their outputs in downstream tasks and applications in which they are employed, which in turn may have real-world consequences for individuals and social groups. By eliciting LLMs’ responses to language-based psychometric inventories we can bring their traits to light. Psychometric profiling enables researchers to study and compare LLMs in terms of non-cognitive characteristics thereby providing a window into the personalities, values, beliefs and biases these models exhibit (or mimic). We discuss the history of similar ideas and outline possible psychometric approaches for LLMs. We demonstrate one promising approach, zero-shot classification, for several LLMs and psychometric inventories. We conclude by highlighting open challenges and future avenues of research for AI Psychometrics

A sociedade do desprezo: por uma nova teoria crítica Disrespect: the normative foundations of critical theory

In the past few years, Reddit -- a community-driven platform for submitting, commenting and rating links and text posts -- has grown exponentially, from a small community of users into one of the largest online communities on the Web. To the best of our knowledge, this work represents the most comprehensive longitudinal study of Reddit's evolution to date, studying both (i) how user submissions have evolved over time and (ii) how the community's allocation of attention and its perception of submissions have changed over 5 years based on an analysis of almost 60 million submissions. Our work reveals an ever-increasing diversification of topics accompanied by a simultaneous concentration towards a few selected domains both in terms of posted submissions as well as perception and attention. By and large, our investigations suggest that Reddit has transformed itself from a dedicated gateway to the Web to an increasingly self-referential community that focuses on and reinforces its own user-generated image- and textual content over external sources.Comment: Published in the proceedings of WWW'14 companio