Miracle-dz/UniFAR-FTUs huggingface dataset:
Immunolocalization of the cellular prion protein in normal brain

We examined the localization of PrPc in normal brain using free‐floating section immunohistochemistry and monclonal antibody 3F4. In the mature hamster and baboon brain, PrPc is localized to the neuropil with a synaptic distribution and the PrPc immunoreactivity is denser in regions known for ongoing plasticity. Cell bodies and major fiber tracts have little or no PrPc immunoreactivity. At the electron microscopic level, PrPc immunoreactivity decorates synaptic profiles, both pre‐ and postsynaptically. Results obtained with two additional antibodies, 3B5 and Pri‐304, showed similar patterns of PrPc bands on Western blots, although Pri‐304 was less sensitive. On sections through the adult hamster hippocampus, 3B5 and Pri‐304 both stained the synaptic neuropil while cell bodies in the pyramidal and dentate granule cell layers were not immunoreactive. Pri‐304 differentiated between synaptic layers in the hippocampus and closely resembled the pattern of staining obtained with 3F4. Preliminary results of developing brain showed that PrPc is initially localized along fiber tracts in the neonate brain. These results show that PrPc has a synaptic distribution in the adult brain and suggest that there are important changes in its distribution during brain development. These results also characterize two additional reagents for studies of PrPc localization. Microsc. Res. Tech. 50:58–65, 2000. © 2000 Wiley‐Liss, Inc.
Substitution and Dropout Bias in Social Experiments: A Study of an Influential Social Experiment

This paper considers the interpretation of evidence from social experiments when persons randomized out of a program being evaluated have good substitutes for it, and when persons randomized into a program drop out to pursue better alternatives. Using data from an experimental evaluation of a classroom training program, we document the empirical importance of control group substitution and treatment group dropping out. Evidence that one program is ineffective relative to close substitutes is not evidence that the type of service provided by all of the programs is ineffective, although that is the way experimental evidence is often interpreted.
How Color Enhances Visual Memory for Natural Scenes

We offer a framework for understanding how color operates to improve visual memory for images of the natural environment, and we present an extensive data set that quantifies the contribution of color in the encoding and recognition phases. Using a continuous recognition task with colored and monochrome gray-scale images of natural scenes at short exposure durations, we found that color enhances recognition memory by conferring an advantage during encoding and by strengthening the encoding-specificity effect. Furthermore, because the pattern of performance was similar at all exposure durations, and because form and color are processed in different areas of cortex, the results imply that color must be bound as an integral part of the representation at the earliest stages of processing.
f4: Facebook's Warm BLOB Storage System

Facebook's corpus of photos, videos, and other Binary Large OBjects (BLOBs) that need to be reliably stored and quickly accessible is massive and continues to grow. As the footprint of BLOBs increases, storing them in our traditional storage system, Haystack, is becoming increasingly inefficient. To increase our storage efficiency, measured in the effective-replication-factor of BLOBs, we examine the underlying access patterns of BLOBs and identify temperature zones that include hot BLOBs that are accessed frequently and warm BLOBs that are accessed far less often. Our overall BLOB storage system is designed to isolate warm BLOBs and enable us to use a specialized warm BLOB storage system, f4. f4 is a new system that lowers the effective-replication-factor of warm BLOBs while remaining fault tolerant and able to support the lower throughput demands. f4 currently stores over 65PBs of logical BLOBs and reduces their effective-replication-factor from 3.6 to either 2.8 or 2.1. f4 provides low latency; is resilient to disk, host, rack, and datacenter failures; and provides sufficient throughput for warm BLOBs.
Reduced alpha 1- and beta 2-adrenoceptor-mediated positive inotropic effects in human end-stage heart failure.

1. alpha 1-Adrenoceptor (phenylephrine in the presence of propranolol) and beta 2-adrenoceptor (fenoterol)-mediated positive inotropic effects were investigated in human ventricular preparations isolated from five non-failing (prospective organ donors) and from eight explanted failing hearts with end-stage idiopathic dilative cardiomyopathy (NYHA IV). 2. For comparison, the nonselective beta-adrenoceptor agonist isoprenaline, the phosphodiesterase (PDE) inhibitor 3-isobutyl-1-methylxanthine (IBMX), the cardiac glycoside dihydroouabain, and calcium were studied. 3. Furthermore, the influence of IBMX on adenosine 3':5'-cyclic monophosphate (cyclic AMP) PDE activity as well as total beta-adrenoceptor density, beta 1- and beta 2-adrenoceptor subtype distribution, and alpha 1-adrenoceptor density were compared in nonfailing and failing human heart preparations. The radioligands (-)-[125I]-iodocyanopindolol for beta-adrenoceptor binding and [3H]-prazosin for alpha 1-adrenoceptor binding were used. 4. The inotropic responses to calcium and dihydroouabain in failing human hearts were unchanged, whereas the maximal alpha 1- and beta 2-adrenoceptor-mediated positive inotropic effects were greatly reduced. The inotropic effects of the other cyclic AMP increasing compounds, i.e. isoprenaline and IBMX, were also reduced to about 60% of the effects observed in nonfailing controls. The potency of these compounds was decreased by factors 4-10. 5. The basal PDE activity and the PDE inhibition by IBMX were similar in nonfailing and failing preparations. 6. The total beta-adrenoceptor density in nonfailing hearts was about 70 fmol mg-1 protein. In failing hearts the total number of beta-adrenoceptors was markedly reduced by about 60%. The betal/beta2-adrenoceptor ratio was shifted from about 80/20% in nonfailing to approximately 60/40% in failing hearts which was due to a selective reduction of beta1-adrenoceptors. The beta2-adrenoceptor population remaining unchanged. alpha-Adrenoceptor density was increased from about 4 fmol mg-' protein in nonfailing to 10 fmol mgprotein in failing hearts.7. Changes in PDE activity and adrenoceptor downregulation cannot completely explain the reduced positive inotropic effects of alpha 1- and beta 2-adrenoceptor agonists in failing human hearts. This supports the hypothesis that impairment of other processes such as the coupling between receptor and effector system, i.e. the respective G-proteins, are equally important in end-stage heart failure.
Imbibition, but Not Release from Stratification, Sets the Circadian Clock in Arabidopsis Seedlings

Circadian rhythms in the abundance of the CAT2 catalase mRNA were not seen in etiolated seedlings but developed upon illumination. These circadian oscillations were preceded by a rapid and transient induction of CAT2 mRNA abundance that varied strikingly according to the timing (circadian phase) of the onset of illumination. This variation oscillated with a circadian periodicity of ~28 hr, indicating that the circadian oscillator is running in etiolated seedlings and regulates (gates) the induction of CAT2 by light. Moreover, because we assayed populations of seedlings, we infer that the individual clocks among populations of etiolated seedlings were synchronized before the onset of illumination. What developmental or environmental signals synchronized the clocks among seedlings? Varying the phase of the onset of illumination relative to release from stratification failed to affect the acute induction of CAT2, indicating that the temperature step from 4 to 22°C associated with release from stratification did not reset the circadian clock. However, the acute induction of CAT2 mRNA varied with time after imbibition, demonstrating that imbibition provides a signal capable of resetting the circadian clock and of synchronizing the clocks among populations of seedlings.
Testing Alternative Theories of the Firm: Transaction Cost, Knowledge-Based, and Measurement Explanations for Make-or- Buy Decisions in Information Services

Firms' boundary choices have undergone careful examination in recent years, particularly in information services. While transaction cost economics provides a widely tested explanation for boundary choice, more recent theoretical work advances competing knowledge-based and measurement cost explanations. Similar to transaction cost economics, these theories examine the impact of exchange attributes on the performance of markets and hierarchies as institutions of governance. These theories, however, offer alternative attributes or alternative mechanisms through which the same attributes influence make-buy choices. Traditional empirical specifications of make-buy models are unable to comparatively test among these alternative theories. By developing and testing a model of comparative institutional performance rather than institutional choice, we examine the degree of support for these competing explanations of boundary choice. Hypotheses are tested using data on the governance of nine information services at 152 companies. Our results suggest that a theory of the firm and a theory of boundary choice is likely to be complex, requiring integration of transaction cost, knowledge-based, and measurement reasoning.
A Reevaluation of Tetraploidy in the Alzheimer’s Disease Brain

Alzheimer’s disease (AD) is characterized by extensive neuronal death in distinct brain regions, including the frontal cortex and hippocampus, although the specific mechanisms of neuronal degeneration in AD remain a topic of intense scientific pursuit. One model for cell death in AD postulates that abortive cell cycle events in neurons, including tetraploidy, precede neuronal death, and novel therapeutics based on suppressing cell cycle re-entry are being pursued. Using DNA content fluorescence-activated cell sorting combined with fluorescence in situ hybridization and immunostaining, we analyzed neuronal nuclei from postmortem human brain samples from the frontal cortex and hippocampus of nondiseased and AD patients for evidence of tetraploidy. Here, we show that tetraploid nuclei are similarly prevalent in AD and control brains and are exclusively non-neuronal, contrasting with an absence of tetraploid neurons. Our findings demonstrate that neuronal tetraploidy is nonexistent in the AD brain and intimate a reevaluation of neuronal cell cycle re-entry as a therapeutic target for AD.
Role of mineralization inhibitors in the regulation of hard tissue biomineralization: relevance to initial enamel formation and maturation

Vertebrate mineralized tissues, i.e., enamel, dentin, cementum, and bone, have unique hierarchical structures and chemical compositions. Although these tissues are similarly comprised of a crystalline calcium apatite mineral phase and a protein component, they differ with respect to crystal size and shape, level and distribution of trace mineral ions, the nature of the proteins present, and their relative proportions of mineral and protein components. Despite apparent differences, mineralized tissues are similarly derived by highly concerted extracellular processes involving matrix proteins, proteases, and mineral ion fluxes that collectively regulate the nucleation, growth and organization of forming mineral crystals. Nature, however, provides multiple ways to control the onset, rate, location, and organization of mineral deposits in developing mineralized tissues. Although our knowledge is quite limited in some of these areas, recent evidence suggests that hard tissue formation is, in part, controlled through the regulation of specific molecules that inhibit the mineralization process. This paper addresses the role of mineralization inhibitors in the regulation of biological mineralization with emphasis on the relevance of current findings to the process of amelogenesis. Mineralization inhibitors can also serve to maintain driving forces for calcium phosphate precipitation and prevent unwanted mineralization. Recent evidence shows that native phosphorylated amelogenins have the capacity to prevent mineralization through the stabilization of an amorphous calcium phosphate precursor phase, as observed in vitro and in developing teeth. Based on present findings, the authors propose that the transformation of initially formed amorphous mineral deposits to enamel crystals is an active process associated with the enzymatic processing of amelogenins. Such processing may serve to control both initial enamel crystal formation and subsequent maturation.
The Hidden Life of Latent Variables: Bayesian Learning with Mixed Graph Models

Directed acyclic graphs (DAGs) have been widely used as a representation of conditional independence in machine learning and statistics. Moreover, hidden or latent variables are often an important component of graphical models. However, DAG models suffer from an important limitation: the family of DAGs is not closed under marginalization of hidden variables. This means that in general we cannot use a DAG to represent the independencies over a subset of variables in a larger DAG. Directed mixed graphs (DMGs) are a representation that includes DAGs as a special case, and overcomes this limitation. This paper introduces algorithms for performing Bayesian inference in Gaussian and probit DMG models. An important requirement for inference is the specification of the distribution over parameters of the models. We introduce a new distribution for covariance matrices of Gaussian DMGs. We discuss and illustrate how several Bayesian machine learning tasks can benefit from the principle presented here: the power to model dependencies that are generated from hidden variables, but without necessarily modeling such variables explicitly.
Effect of Using Internet Tools on Enhancing EFL Students' Speaking Skill

This quasi-experimental study aimed to examine the effect of using shared online oral diaries on the EFL Saudi First year university students’ speaking proficiency. It used one male and one female EFL Saudi First year university students classroom sections to represent the experimental group and one male and one female classroom sections to represent the control group. An equivalent speaking proficiency test, developed by the researcher, was applied on the control and the experimental groups before the study started to ensure their equivalence; and was also used as a post-test. The results of the post-test revealed significant differences between the mean scores of the experimental group and the mean scores of the control group in favor of the experimental group.
Imaging Intratumoral Convection: Pressure-Dependent Enhancement in Chemotherapeutic Delivery to Solid Tumors

Purpose: Low–molecular weight (LMW) chemotherapeutics are believed to reach tumors through diffusion across capillary beds as well as membrane transporters. Unexpectedly, the delivery of these agents seems to be augmented by reductions in tumor interstitial fluid pressure, an effect typically associated with high–molecular weight molecules that reach tumors principally through convection. We investigated the hypothesis that improved intratumoral convection can alter tumor metabolism and enhance the delivery of a LMW chemotherapeutic agent to solid tumors. Experimental Design: For this purpose, we applied 31P/19F magnetic resonance spectroscopy (MRS) and magnetic resonance spectroscopic imaging (MRSI) to examine the influence of type I collagenase on tumor bioenergetics and the delivery of 5-fluorouracil (5FU) to HT29 human colorectal tumors grown s.c. in mice. Results: Collagenase effected a 34% reduction in tumor interstitial fluid pressure with an attendant disintegration of intratumoral collagen. Neither mice-administered collagenase nor controls receiving PBS showed changes in 31phosphorus MRS–measured tumor bioenergetics; however, a time-dependent increase in the content of extracellular inorganic phosphate (Pie) was observed in tumors of collagenase-treated animals. 31Phosphorus MRSI showed that this increase underscored a more homogeneous distribution of Pie in tumors of experimental mice. 19Fluorine MRS showed that these changes were associated with a 50% increase in 5FU uptake in tumors of experimental versus control animals; however, this increase resulted in an increase in 5FU catabolites rather than fluoronucleotide intermediates that are required for subsequent cytotoxicity. Conclusions: These data indicate that the modulation of convective flow within tumors can improve the delivery of (LMW) chemotherapeutics and show the potential role for noninvasive imaging of this process in vivo.
Optimized Spatial Hashing for Collision Detection of Deformable Objects

We propose a new approach to collision and self– collision detection of dynamically deforming objects that consist of tetrahedrons. Tetrahedral meshes are commonly used to represent volumetric deformable models and the presented algorithm is integrated in a physically–based environment, which can be used in game engines and surgical simulators. The proposed algorithm employs a hash function for compressing a potentially infinite regular spatial grid. Although the hash function does not always provide a unique mapping of grid cells, it can be generated very efficiently and does not require complex data structures, such as octrees or BSPs. We have investigated and optimized the parameters of the collision detection algorithm, such as hash function, hash table size and spatial cell size. The algorithm can detect collisions and self– collisions in environments of up to 20k tetrahedrons in real–time. Although the algorithm works with tetrahedral meshes, it can be easily adapted to other object primitives, such as triangles.
The value of relationship banking during financial crises: evidence from the Republic of Korea

A systemic financial crisis with monetary restriction is probably the most promising occasion for assessing whether, and to what extent, relationship banking is valuable to borrowers. The authors take this question to a unique database of credit bureau, microeconomic information covering the pervasive financial crisis the Republic of Korea experienced in 1997-98. The database includes all corporate borrowers surveyed by the Korean Credit Bureau, providing details on the structure of their borrowings, and on their relationship with lending banks. The authors did not have access to the identity of the corporate borrower, and their only non-financial control variable was the borrower's Standard Industrial Classification (SIC). This restriction limited their analysis to smaller borrowers, keeping their sample focused on small, and medium-size enterprises, which were likely to rely on banks for external financing. Their findings: 1) Outstanding loans plunge more for firms with weaker pre-crisis relationship banking. 2) The drop in credit lines - arguably a proxy identifying shifts in the loan supply - is larger for firms relying less on strong relationship banking. 3) More intense pre-crisis relationship banking reduces the probability that a previously non-delinquent firm would build (increase) its loans in arrears in 1998, the year of the sharpest liquidity constraints. 4) All things equal, this probability depends on whether firms were borrowing from one (or more) of the five banks foreclosed in June 1998, showing that it might be particularly difficult for borrowers to replace distressed lending banks during a financial crisis. The authors'findings support the hypothesis that relationship banking = with surviving banks - has a positive value during a systemic financial crisis. They argue that for many viable small, and medium-size businesses in Korea, relationship banking reduced liquidity constraints, and thus, diminished the probability of unwarranted bankruptcy.
[Microbiological conditions of hospital beds before and after terminal cleaning].

INTRODUCTION The hospital's environment keeps a close relationship with hospital infection, which may promote focus of contact and transmission. The terminal cleaning of patient unit represents one way to control microbiological environmental contamination. The study has as its main objective to evaluate the microbiological conditions of hospital mattresses before and after cleaning. METHODS Rodac plates were utilized for specimen collection with culture medium - blood agar plate. The patients beds were chosen by criteria established before hand and the places for specimen collection in the mattress were chosen by aleatory drawing. To the study of numerical alteration related to the positivity of plates before and after cleaning, Goodman' statistics tests were used. RESULTS From 52 mattress investigated, 520 culture plates were done from which 514 (98,8%) had a positive culture, 259 before cleaning and 255 after cleaning showing a reduction of positive cultures in only 4 plates after cleaning. CONCLUSIONS The number of plates with countable and countless colonies suggests that the cleaning, as it is done, instead of reducing the microorganism is dislocating it to other areas of the mattress keeping the microbiological condition as it was before the cleaning process.
Outbreak of Burkholderia cepacia complex bacteremia in a chemotherapy day care unit due to intrinsic contamination of an antiemetic drug

Background: In the end of 2009, a large number of patients with cancer undergoing chemotherapy at the day care unit of a private hospital in Mumbai, India developed Burkholderia cepacia complex (BCC) blood stream infection (BSI). Objective: The objectives were to identify the source of the outbreak and terminate the outbreak as rapidly as possible. Materials and Methods: All infection control protocols and processes were reviewed. Intensive training was started for all nursing staff involved in patient care. Cultures were sent from the environment (surfaces, water, air), intravenous fluids, disinfectants and antiseptics and opened/unopened medication. Results: A total of 13 patients with cancer with tunneled catheters were affected with BCC BSI. The isolates were of similar antimicrobial sensitivity. No significant breach of infection control protocols could be identified. Cultures from the prepared intravenous medication bags grew BCC. Subsequently, culture from unused vials of the antiemetic granisetron grew BCC, whereas those from the unopened IV fluid bag and chemotherapy medication were negative. On review, it was discovered that the outbreak started when a new brand of granisetron was introduced. The result was communicated to the manufacturer and the brand was withdrawn. There were no further cases. Conclusions: This outbreak was thus linked to intrinsic contamination of medication vials. We acknowledge a delay in identifying the source as we were concentrating more on human errors in medication preparation and less on intrinsic contamination. We recommend that in an event of an outbreak, unopened vials be cultured at the outset.
A Quantitative Assessment of Performance in Mobile App Development Tools

The popularity and maturity of mobile cross-platform tools increased considerably during the last years. They can be used to increase the efficiency during the development cycle of mobile applications. Although it is common knowledge that cross-platform tools come with a performance penalty, the size of the overhead is unclear. Our study targets the assessment of two representative cross-platform tools. This paper presents a quantitative performance analysis that is applied to a non-trivial, multi-screen app. Relevant performance properties on both low-end and high-end devices are evaluated and compared to a native Android and iOS implementation. We further reflect about the impact of the results on the user acceptance and experience, and define guidelines for the selection of a particular tool.