Miracle-dz/UniFAR-FTUs huggingface dataset:
The effects of Clostridium perfringens enterotoxin on morphology, viability, and macromolecular synthesis in vero cells

Vero (African green monkey kidney) cells grown in tissue culture monolayer were sensitive to Clostridium perfringens enterotoxin. Within 30 minutes of exposure to the enterotoxin gross morphological damage was observed and within 40 minutes approximately 75% of the cells had detached. Nearly half of the cells were nonviable following 35 to 40 minutes incubation with the enterotoxin. Doses as low as 0.1 ng caused small but detectable inhibition of plating efficiency of the cells while more than 100 ng caused the inhibition to approach 100%. Total inhibition of DNA, RNA, and protein synthesis occurred within 30 minutes exposure to enterotoxin. Heat inactivated enterotoxin had no apparent effects upon cellular morphology, detachment, viability, plating efficiency, or incorporation. We propose that the enterotoxin induces structural damage to the cytoplasmic membrane which results in loss of electrolytes and other essential substances from the cells. The outcome of this process is shut down of macromolecular synthesis, gross morphological damage, and eventual death of the cell.
Centralized Coded Caching Schemes: A Hypergraph Theoretical Approach

The centralized coded caching scheme is a technique proposed by Maddah-Ali and Niesen as a method to reduce the network burden in peak times in a wireless network system. Yan <italic>et al.</italic> reformulate the problem as designing a corresponding placement delivery array and propose two new schemes from this perspective. These schemes significantly reduce the rate compared with the uncoded caching schemes. However, to implement these schemes, each file should be cut into <inline-formula> <tex-math notation="LaTeX">$F$ </tex-math></inline-formula> pieces, where <inline-formula> <tex-math notation="LaTeX">$F$ </tex-math></inline-formula> grows exponentially with the number of users <inline-formula> <tex-math notation="LaTeX">$K$ </tex-math></inline-formula>. Such a constraint is obviously infeasible in the practical setting, especially when <inline-formula> <tex-math notation="LaTeX">$K$ </tex-math></inline-formula> is large. Thus, it is desirable to design caching schemes with constant rate <inline-formula> <tex-math notation="LaTeX">$R$ </tex-math></inline-formula> (independent of <inline-formula> <tex-math notation="LaTeX">$K$ </tex-math></inline-formula>) as well as smaller <inline-formula> <tex-math notation="LaTeX">$F$ </tex-math></inline-formula>. In this paper, we view the centralized coded caching problem in a hypergraph perspective and show that designing a feasible placement delivery array is equivalent to constructing a linear and (6,3)-free 3-uniform 3-partite hypergraph. Several new results and constructions arise from our novel point of view. First, by using the famous (6,3)-theorem in extremal graph theory, we show that constant rate placement delivery arrays with <inline-formula> <tex-math notation="LaTeX">$F$ </tex-math></inline-formula> growing linearly with <inline-formula> <tex-math notation="LaTeX">$K$ </tex-math></inline-formula> do not exist. Second, we present two infinite classes of placement delivery arrays to show that constant rate caching schemes with <inline-formula> <tex-math notation="LaTeX">$F$ </tex-math></inline-formula> growing sub-exponentially with <inline-formula> <tex-math notation="LaTeX">$K$ </tex-math></inline-formula> do exist.
The numerical steepest descent path method to calculate physical optics radiations with concave phase variations

In this work, we develop the numerical steepest descent path (NSDP) algorithm to calculate the physical optics (PO) integrals with the quadratic concave phase variations. All the high frequency critical points contributions, including the stationary phase points (SPP), the boundary resonance points (RP) and the vertex points (VP) are clearly expressed. In order to illustrate the transition effect of the critical points, we extend the NSDP method to calculate the PO integrals with the coalescence of the critical points. Numerical results of triangular domains are given to verify the efficiency. The NSDP method could achieve the frequency independent computational workload and obtain accurate results. Together with the PO integrals with the quadratic parabolic and hyperbolic phase terms, this work makes the NSDP theory be complete for treating the PO integrals with quadratic phase variations.
MicroTE: fine grained traffic engineering for data centers

The effects of data center traffic characteristics on data center traffic engineering is not well understood. In particular, it is unclear how existing traffic engineering techniques perform under various traffic patterns, namely how do the computed routes differ from the optimal routes. Our study reveals that existing traffic engineering techniques perform 15% to 20% worse than the optimal solution. We find that these techniques suffer mainly due to their inability to utilize global knowledge about flow characteristics and make coordinated decision for scheduling flows. To this end, we have developed MicroTE, a system that adapts to traffic variations by leveraging the short term and partial predictability of the traffic matrix. We implement MicroTE within the OpenFlow framework and with minor modification to the end hosts. In our evaluations, we show that our system performs close to the optimal solution and imposes minimal overhead on the network making it appropriate for current and future data centers.
Evaluation of Corneal Refraction in a Model of a Gaze Tracking System

The complexity of corneal refraction modeling complicates geometrical analysis of gaze tracking systems. The task can be accomplished in different ways by means of different approximations. Depending on the assumptions made, errors can arise and the accuracy of trackers can end up determined to an excessive degree by the hardware setup and subject parameters. In this study, keeping the hardware and eye model the same, we compare different methods for evaluation of corneal refraction. Our results show that the approximated methods are sensitive to the calibration of the system and less robust to noise. The nonapproximated method removes any dependency on setup and allows clear differentiation between hardware and subject's calibration.
Isolation and Characterization of Phages Infecting Bacillus subtilis

Bacteriophages have been suggested as an alternative approach to reduce the amount of pathogens in various applications. Bacteriophages of various specificity and virulence were isolated as a means of controlling food-borne pathogens. We studied the interaction of bacteriophages with Bacillus species, which are very often persistent in industrial applications such as food production due to their antibiotic resistance and spore formation. A comparative study using electron microscopy, PFGE, and SDS-PAGE as well as determination of host range, pH and temperature resistance, adsorption rate, latent time, and phage burst size was performed on three phages of the Myoviridae family and one phage of the Siphoviridae family which infected Bacillus subtilis strains. The phages are morphologically different and characterized by icosahedral heads and contractile (SIOΦ, SUBω, and SPOσ phages) or noncontractile (ARπ phage) tails. The genomes of SIOΦ and SUBω are composed of 154 kb. The capsid of SIOΦ is composed of four proteins. Bacteriophages SPOσ and ARπ have genome sizes of 25 kbp and 40 kbp, respectively. Both phages as well as SUBω phage have 14 proteins in their capsids. Phages SIOΦ and SPOσ are resistant to high temperatures and to the acid (4.0) and alkaline (9.0 and 10.0) pH.
Music Teacher Perceptions of Issues and Problems in Urban Elementary Schools

The purpose of this study was to examine the perceptions of music teachers in urban elementary schools. Title I public elementary schools (N = 221) in two counties in the Southeastern United States were surveyed for demographic information, and 71 of the music teachers from those schools participated in the survey designed for this study. The Doyle (2009) survey reported an overall Cronbach's alpha of 0.91. The survey was intended to accumulate data representing urban music education in respect to the independent variables of student demographics, teacher demographics, student/teacher demographic differences, teacher preparation, and teacher support; the dependent variables examined were teacher attitudes about urban elementary music teaching and teacher expectations of their urban elementary music students. Results indicated that most of the teachers mismatched demographically with their students. Teacher/student socioeconomic matches were correlated with Attitudes; teacher/student ethnicity and socioeconomic status matches were correlated with Expectations. Professional support was positively correlated with preparation. Support was negatively correlated with the socioeconomic variables, and positively correlated with both attitudes and expectations.
A Descriptive Analysis of Error Correction in Instrumental Music Rehearsals

This study is a description of the error correction process in 40 instrumental music rehearsals taught by 10 teachers, each of whom was observed conducting 4 consecutive rehearsals. A total of 332 rehearsal frames were analyzed. Rather than summing the observation data across complete rehearsals, I analyzed the data using rehearsal frames as a unit of analysis. Perhaps the most important finding was that the error correction process, rate of teacher-student interaction, and pace varied systematically with the type of error addressed.
Motivation and Its Relationship With Reading Achievement in an Urban Middle School

ABSTRACT The authors investigated the effects of intrinsic and extrinsic motivation on reading achievement for urban middle school students. The authors initially developed a research-based theoretical model representing interrelationships among students' ethnicity, gender, grade level, intrinsic motivation, extrinsic motivation, and reading achievement. When the authors tested the model, structural equation models (SEMs) produced effects that were statistically significant. For example, a multiple-groups SEM analysis indicated that intrinsic motivation had a stronger positive relationship with reading achievement for Asian students than for Hispanic students. Analysis by gender, ethnicity, and grade level showed statistically significant decreases over time for intrinsic and extrinsic motivation. Results suggest a significant decline in overall motivation to read during the middle school years for students in urban schools.
Neuropeptide FF (NPFF) Analogs Functionally Antagonize Opioid Activities in NPFF2 Receptor-Transfected SH-SY5Y Neuroblastoma Cells

To elucidate the mechanism of the cellular antiopioid activity of neuropeptide FF (NPFF), we have transfected the SH-SY5Y neuroblastoma cell line, which expresses μ-and δ-opioid receptors, with the human NPFF2 receptor. The selected clone, SH2-D9, expressed high-affinity NPFF2 receptors in the same range order as μ- and δ-opioid receptors (100–300 fmol/mg of protein). The NPFF analog [d-Tyr1, (NMe)Phe3]NPFF (1DMe) did not modify the binding parameters of the μ- and δ-specific agonists [d-Ala2,N-Me-Phe4,Gly5-ol]-enkephalin and deltorphin-I, respectively. 1DMe dose dependently inhibited 75 to 80% of the cAMP production stimulated by forskolin. Preincubation with 1DMe halved the maximal inhibition of N-type Ca2+ channels by opioid agonists. In the presence of carbachol, acting on muscarinic receptors to release Ca2+ from the intracellular stores, deltorphin-I and 1DMe enhanced this release. Preincubation with 1DMe reduced the maximal effect of deltorphin-I by 40%, demonstrating an antiopioid effect in this experimental model for the first time. By using peptides corresponding to the carboxyl terminus of the αi1,2, αi3, αo, and αs subunits of G proteins, which specifically uncouple receptors from G proteins, we demonstrated that μ-opioid and NPFF2 receptors couple to the four subunits assayed. The Ca2+ release from the intracellular stores by 1DMe resulted from the coupling of NPFF2 receptors with Gαo and Gαi1,2, whereas the coupling with Gαs reduced the antiopioid effect of 1DMe in the modulation of N-type channels. This SH2-D9 cell line now provides the opportunity to study the interaction between both receptors.
No Evidence for Pre-Copulatory Sexual Selection on Sperm Length in a Passerine Bird

There is growing evidence that post-copulatory sexual selection, mediated by sperm competition, influences the evolution of sperm phenotypes. Evidence for pre-copulatory sexual selection effects on sperm traits, on the other hand, is rather scarce. A recent paper on the pied flycatcher, Ficedula hypoleuca, reported phenotypic associations between sperm length and two sexually selected male traits, i.e. plumage colour and arrival date, thus invoking pre-copulatory sexual selection for longer sperm. We were unable to replicate these associations with a larger data set from the same and two additional study populations; sperm length was not significantly related to either male plumage colour or arrival date. Furthermore, there was no significant difference in sperm length between populations despite marked differences in male plumage colour. We also found some evidence against the previously held assumption of longer sperm being qualitatively superior; longer sperm swam at the same speed as shorter sperm, but were less able to maintain speed over time. We argue that both empirical evidence and theoretical considerations suggest that the evolution of sperm morphology is not primarily associated with pre-copulatory sexual selection on male secondary sexual traits in this or other passerine bird species. The relatively large between-male variation in sperm length in this species is probably due to relaxed post-copulatory sexual selection.
Physical Activity and Social Physique Anxiety in Older Women: The Moderating Effects of Self-Presentation Efficacy

Given the inconsistent relationships observed between social physique anxiety (SPA) and physical activity, it is possible that other variables moderate this relationship. This study examined self-presentation efficacy (SPE) as a potential moderator. Participants were 81 older women. Multiple regression analysis revealed that SPA, SPE, and the SPA x SPE interaction significantly predicted physical activity, with the SPA x SPE interaction explaining 6% of the variance in activity. Evaluation of this interaction indicated that SPA was negatively correlated with activity only for women with high and mean SPE and was unrelated to activity for women with low SPE. These findings suggest that, for older women, lower levels of SPA are not always related to greater activity. Rather, SPE is an important moderator of the SPA-physical activity relationship.
Kinetics of Bartonella birtlesii Infection in Experimentally Infected Mice and Pathogenic Effect on Reproductive Functions

ABSTRACT The kinetics of infection and the pathogenic effects on the reproductive function of laboratory mice infected with Bartonella birtlesii recovered from an Apodemus species are described. B. birtlesii infection, as determined by bacteremia, occurred in BALB/c mice inoculated intravenously. Inoculation with a low-dose inoculum (1.5 × 103 CFU) induced bacteremia in only 75% of the mice compared to all of the mice inoculated with higher doses (≥1.5 × 104). Mice became bacteremic for at least 5 weeks (range, 5 to 8 weeks) with a peak ranging from 2 × 103 to 105 CFU/ml of blood. The bacteremia level was significantly higher in virgin females than in males but the duration of bacteremia was similar. In mice infected before pregnancy (n = 20), fetal loss was evaluated by enumerating resorption and fetal death on day 18 of gestation. The fetal death and resorption percentage of infected mice was 36.3% versus 14.5% for controls (P < 0.0001). Fetal suffering was evaluated by weighing viable fetuses. The weight of viable fetuses was significantly lower for infected mice than for uninfected mice (P < 0.0002). Transplacental transmission of Bartonella was demonstrated since 76% of the fetal resorptions tested was culture positive for B. birtlesii. The histopathological analysis of the placentas of infected mice showed vascular lesions in the maternal placenta, which could explain the reproductive disorders observed. BALB/c mice appeared to be a useful model for studyingBartonella infection. This study provides the first evidence of reproductive disorders in mice experimentally infected with a Bartonella strain originating from a wild rodent.
Response statistics dissect the contributions of different sources of variability to population activity in V1

Response variability, as measured by fluctuating responses upon repeated performance of trials, is a major component of neural responses, and its characterization is key to interpret high dimensional population recordings. Response variability and covariability display predictable changes upon changes in stimulus and cognitive or behavioral state, providing an opportunity to test the predictive power of models of neural variability. Still, there is little agreement on which model to use as a building block for population-level analyses, and models of variability are often treated as a subject of choice. We investigate two competing models, the Doubly Stochastic Poisson (DSP) model assuming stochasticity at spike generation, and the Rectified Gaussian (RG) model that traces variability back to membrane potential variance, to analyze stimulus-dependent modulation of response statistics. Using a model of a pair of neurons, we demonstrate that the two models predict similar single-cell statistics. However, DSP and RG models have contradicting predictions on the joint statistics of spiking responses. In order to test the models against data, we build a population model to simulate stimulus change-related modulations in response statistics. We use unit recordings from the primary visual cortex of monkeys to show that while model predictions for variance are qualitatively similar to experimental data, only the RG model's predictions are compatible with joint statistics. These results suggest that models using Poisson-like variability might fail to capture important properties of response statistics. We argue that membrane potential-level modelling of stochasticity provides an efficient strategy to model correlations.
The hypolipidaemic effects of Spirulina (Arthrospira platensis) supplementation in a Cretan population: a prospective study.

BACKGROUND Spirulina (Arthrospira platensis) is a filamentous cyanobacterium used as a food supplement. The objective of the study was to determine the lipid-lowering effects of Spirulina in Cretan Greek dyslipidaemic patients, and to document its effectiveness as a possible alternative treatment for dyslipidaemia. Fifty-two adultCretan outpatients (32 men, 20 women), median age 47 (range, 37-61) years, with recently diagnosed dyslipidaemia, consumed orally 1 g Spirulina (Greek production) per day for 12 weeks. The full lipid profile was measured in fasting blood samples at the beginning and end of the study period. Anthropometric measurements including systolic and diastolic blood pressure, height, weight and body mass index were also recorded. RESULTS At the end of the 3-month intervention period the mean levels of triglycerides, low density lipoprotein-cholesterol, total cholesterol, non-high density lipoprotein-cholesterol levels, and the ratio of total cholesterol to high-density lipoproteincholesterol were significantly decreased: 16.3% (P < 0.0001), 10.1% (P < 0.0001), 8.9% (P < 0.0001), 10.8% (P < 0.0001) and 11.5% (P = 0.0006) respectively, whereas the mean high-density lipoprotein-cholesterol levels were not significantly increased (3.5%). Blood pressure, weight and body mass index remained almost unchanged. CONCLUSIONS Spirulina supplementation at a dose of 1 g daily has powerful hypolipidaemic effects, especially on the triglyceride concentration in dyslipidaemic Cretan outpatients.
Drunk Drivers, DWI “Drug Court” Treatment, and Recidivism: Who Fails?

We conducted an evaluation of an experimental Driving-While-Intoxicated (DWI) Drug Court treatment program operated by a single municipal court. Specially trained court personnel assessed first-time (and, as we found out, some second-time) DWI offenders for symptoms of alcoholism. Once court personnel reached a clinical determination that an individual was an alcoholic, research team members randomly assigned that person to either the treatment program or to a control group receiving normal municipal court processing. A third group consisted of a like number of randomly selected, nonalcoholic, first-time offenders. The conviction records of all three groups were tracked for up to 24 months following the initial DWI conviction. We found significantly fewer alcohol-related and other serious crime reconvictions for the nonalcoholic group. Among those determined to be alcoholic, the treatment group had significantly fewer reconvictions than the control group. We address the implications and limitations of our findings for similar experimental studies in criminal justice and for DWI Drug Court treatment programs.
Assessment as Judgment-in-Context: Analysing how teachers evaluate students' writing 1

In this paper, we analyse teachers' judgments of students' written texts. We document how teachers use evidence in ways that depend both on their knowledge of the students and on the assessment framework they need to use. We analyse teachers' judgments by contrasting the structures of assessments made using teachers' normal classroom judgment processes with those made using an external set of “benchmark” standards. We show how the tension between demands for system-wide assessment validity and localised contextually sensitive site validity impacts on the richness and consistency of the judgment processes. We conclude that current understandings of teacher judgment processes that operate in everyday assessment practices generally fail to account for the complexity and dynamism of this routine classroom activity. Furthermore, we demonstrate that the methodology of judgment analysis, combined with think-aloud protocols, has the potential to shed light on the complexities associated with the operation of judgment in educational assessment.
The Changing American Soldier: Work-Related Attitudes of U.S. Army Personnel in World War II and the 1970s

The end of military conscription in the Unites States and the advent of the all-volunteer armed force have placed the American military in the position of competing against civilian sector employers, in the labor market, for quality personnel. Contemporary concerns within the civilian sector regarding quality of work life have made it necessary for the military services to become increasingly concerned with the work-related attitudes of their personnel. Our analysis compared the attitudes of a sample of soldiers in the all-volunteer army in 1973 with those of soldiers in the conscription-based army of World War II. We found that representative samples of enlisted men in 1943 were more positively oriented toward their jobs than are the soldiers of the 1970s. Some similarities were observed between World War II AWOLs and soldiers in the all-volunteer force. The relatively negative attitudes of contemporary soldiers may reflect, at least in part, a postwar demoralization that was observed after the end of hostilities in World War II as well.