Miracle-dz/UniFAR-FTUs huggingface dataset:
Biochemical and Structural Characterization of Mycobacterial Aspartyl-tRNA Synthetase AspS, a Promising TB Drug Target

The human pathogen Mycobacterium tuberculosis is the causative agent of pulmonary tuberculosis (TB), a disease with high worldwide mortality rates. Current treatment programs are under significant threat from multi-drug and extensively-drug resistant strains of M. tuberculosis, and it is essential to identify new inhibitors and their targets. We generated spontaneous resistant mutants in Mycobacterium bovis BCG in the presence of 10× the minimum inhibitory concentration (MIC) of compound 1, a previously identified potent inhibitor of mycobacterial growth in culture. Whole genome sequencing of two resistant mutants revealed in one case a single nucleotide polymorphism in the gene aspS at 535GAC>535AAC (D179N), while in the second mutant a single nucleotide polymorphism was identified upstream of the aspS promoter region. We probed whole cell target engagement by overexpressing either M. bovis BCG aspS or Mycobacterium smegmatis aspS, which resulted in a ten-fold and greater than ten-fold increase, respectively, of the MIC against compound 1. To analyse the impact of inhibitor 1 on M. tuberculosis AspS (Mt-AspS) activity we over-expressed, purified and characterised the kinetics of this enzyme using a robust tRNA-independent assay adapted to a high-throughput screening format. Finally, to aid hit-to-lead optimization, the crystal structure of apo M. smegmatis AspS was determined to a resolution of 2.4 Å.
Lymphoproliferative and Intestinal Malignancies in 214 Patients With Biopsy-defined Celiac Disease

Prior studies have suggested that the incidence of some neoplastic disorders, particularly malignant lymphoma, is increased in celiac disease. In the present study, lymphoproliferative and intestinal cancers in 214 consecutive biopsy-defined celiac disease patients, including 148 females (69.2%) and 66 males (30.8%), seen by a single clinician over more than 20 years were tabulated. Of the 214 patients, 151 were diagnosed with celiac disease before age 60 and 63 at or after age 60. In total, 18 malignant lymphomas and 3 small intestinal adenocarcinomas were detected. While the overall incidence of malignant lymphoma was 8.4%, similar to other European centers, the incidence in elderly celiacs in this study was 22.2%. Celiac disease was detected before or even after the diagnoses of lymphoma or small intestinal adenocarcinoma were established. In some, epithelial lymphocytosis was evident in gastric, colonic, or biliary ductal epithelium. In addition, other immune-mediated disorders, dermatitis herpetiformis, and autoimmune thyroid disease were common, suggesting a distinct clinical and pathologic phenotype in celiac disease that may predispose to malignant complications. Finally, except for a single hypopharyngeal carcinoma in a celiac disease patient with a malignant lymphoma, other malignant disorders of esophagus, stomach, and colon were not detected.
Evaluating Citizen Adoption and Satisfaction of E-Government

Governments at all levels are faced with the challenge of transformation and the need to reinvent government systems in order to deliver efficient and cost effective services. E-government presents a tremendous impetus to move forward in the 21st century with higher quality, cost-effective, government services, and a better relationship between citizens and government. This research considers theoretical foundations from the Technology Acceptance Model TAM, the Web Trust Model WTM, and SERVQUAL to form a parsimonious model of citizen adoption and satisfaction for e-government services. The authors find that usefulness, or end-user convenience, to be the principal determinant of e-government adoption and satisfaction, unaffected even when controlling demographic variables such as race, income, and education are introduced.
Cyclostationary feature detection from sub-Nyquist samples

Wideband spectrum sensing which requires detecting the presence or absence of signals in a wideband channel faces multiple practical issues. Current bandwidth limitations of state-of-the-art analog to digital converters require alternative approaches to be considered for wideband sensing. Cyclostationary feature detection is a promising sensing tool which is robust to noise, and takes advantage of the noise stationarity. In this paper, we propose a cyclostationary feature detector that operates on sub-Nyquist samples obtained via either multicoset sampling or the modulated wideband converter analog front-end, and present the receiver's detection performance at low SNRs.
Time hierarchies for sampling distributions

We show that "a little more time gives a lot more power to sampling algorithms. " We prove that for every constant k ≥ 2, every polynomial time bound t, and every polynomially small ε, there exists a family of distributions on k elements that can be sampled exactly in polynomial time but cannot be sampled within statistical distance 1-1/k-ε in time t. This implies the following general time hierarchy for sampling distributions on arbitrary-size domains such as {0,1}n: For every polynomial time bound t and every constant ε>0, there exists a family of distributions that can be sampled exactly in polynomial time but cannot be sampled within statistical distance 1-ε in time t. Our proof involves reducing the problem to a communication problem over a certain type of noisy channel. To solve the latter problem we use a type of list-decodable code for a setting where there is no bound on the number of errors but each error gives more information than an erasure. This type of code can be constructed using certain known traditional list-decodable codes, but we give a new construction that is elementary, self-contained, and tailored to this setting.
Consequences of media and Internet use for offline and online network capital and well-being. A causal model approach

This study sets out to identify relations between people's media use, network capital as a resource, and loneliness. Unlike many studies on this topic, this study aimed to test hypotheses on a national sample, and used insights from empirical research and theoretical notions from different research areas. Data collected via telephone interviews in 2005 were analyzed with Structural Equation Modeling. The assumption that traditional and new media destroy social capital is not supported empirically. Moreover, online network capital augments offline network capital and web surfing coincides with more online socializing. However, this additional capital appears not to have benefits in terms of social support and loneliness. The reverse causal relation between loneliness and media use also could not be established.
The market for corporate control in Germany : Causes and consequences of changes in ultimate share ownership

Hostile takeovers are rare in Germany. This is often seen as evidence that Germany also lacks a market for corporate control, as it is known for the UK and the US. This study shows that, in contrast to hostile takeovers, friendly takeovers play an important role in Germany. This market for corporate control is large compared with other countries. This study also provides evidence on the causes and consequences of changes in ultimate ownership: Poor performance triggers changes in ultimate ownership, but complex ownership structures based on pyramids and cross-ownership represent an obstacle. Control transfers are followed by increased management and supervisory board turnover, asset restructuring and employee layoffs. Industry-adjusted performance of poorly-performing firms improves, but this result depends on the performance measure chosen.
Mathematics of the Faraday Cage

The amplitude of the gradient of a potential inside a wire cage is investigated, with par- ticular attention to the 2D configuration of a ring of n disks of radius r held at equal potential. The Faraday shielding effect depends upon the wires having finite radius and is weaker than one might expect, scaling as | log r|/n in an appropriate regime of small r and large n. Both numerical results and a mathematical theorem are provided. By the method of multiple scales, a continuum approximation is then derived in the form of a homogenized boundary condition for the Laplace equation along a curve. The homogenized equation reveals that in a Faraday cage, charge moves so as to somewhat cancel an external field, but not enough for the cancellation to be fully effective. Physically, the effect is one of electrostatic induction in a surface of limited capacitance. An alternative discrete model of the effect is also derived based on a principle of energy minimization. Extensions to electromagnetic waves and 3D geometries are mentioned.
[The clinical and evolutional characteristics of visceral leishmaniasis in patients with HIV infection].

OBJECTIVE To analyze the clinical features, yield of the diagnostic techniques, and therapeutic response of HIV-associated visceral leishmaniasis (VL), and compare the initial episodes to the relapses. METHODS Forty-one episodes of leishmaniasis visceral, diagnosed in 31 HIV-positive patients between 1st February 1992 and 31st January 1996 were reviewed. RESULTS The prevalence of VL in HIV-positive patients in our center was 4.2%. Fifty-eight percent of the patients had AIDS prior to the diagnosis of VL. Fever was more frequent in the initial episodes than in the relapses (90.3% versus 60%; p < 0.05; OR: 6.2; IC 95%: 0.8-51.5), splenomegaly was more frequent in the relapses (100% versus 71%; p = 0.05). The diagnostic delay was longer in the initial episodes (27.2 +/- 22.7 versus 5 +/- 4.8 days; p < 0.05). The diagnostic yield of bone marrow biopsy was 82.1%, of liver biopsy 72.7% and of splenic fine-needle aspiration 87.5%. The indirect immunofluorescence test for Leishmania antibodies was positive in 5.9% of cases. Therapeutic failure occurred in 47.6% of patients treated with antimonials and 3.3% of patients treated with amphotericin B. Those patients who received secondary prophylaxis had less relapses than those who did not (17.6% versus 66.7%; p < 0.05; OR: 0.11; IC 95%: 0.01-1.28). Of the 31 patients, twenty-six (83.8%) died, and in none of them was the cause of the death directly related to LV. CONCLUSION HIV-associated VL manifests clinically in a similar fashion to the immunocompetent's disease. It appears in advanced immunosuppression phases, behaving like other AIDS-defining illnesses. In spite of a good therapeutic response the relapse rate is high.
EFFECTS OF LEADERSHIP STYLE ON ORGANIZATIONAL PERFORMANCE: A SURVEY OF SELECTED SMALL SCALE ENTERPRISES IN IKOSI-KETU COUNCIL DEVELOPMENT AREA OF LAGOS STATE, NIGERIA

This study has investigated the effects of leadership style on organizational performance in small scale enterprises. The major objective was to determine effect of leadership styles on performance in small scale enterprises. Transformational and transactional leadership styles were considered in this study. Transformational leadership behaviours and performance/outcome considered relevant in the study were charisma, inspirational motivation and intellectual stimulation/individual consideration; and effectiveness, extra effort and satisfaction, respectively. Transactional leadership bahaviours and performance/outcome variables were constructive/contingent reward and corrective/management by exception; and effort, productivity and loyalty/commitment, respectively. The study followed a survey design, and employed evaluative quantitative analysis method. Analysis was based on primary data generated through a structured Multifactor Leadership Questionnaire (MLQ) administered on respondents. Responses to research statements were scaled and converted to quantitative data via code manual developed for the study to enable segmentation of the data responses into dependent and independent variables based on leadership behaviours and associated performance variables. OLS multiple regression models were specified, estimated and evaluated. The result showed that while transactional leadership style had significant positive effect on performance, transformational leadership style had positive but insignificant effect on performance. The study concluded that transactional leadership style was more appropriate in inducing performance in small scale enterprises than transformational leadership style and, therefore, recommended transactional leadership style for the small enterprises with inbuilt strategies for transition to transformational leadership style as the enterprises developed, grew and matured.
Creating SysML views from an OPM model

Conceptual modeling is key to Model-Based Systems Engineering (MBSE) approaches. OPM - Object-Process Methodology and SysML - OMG Systems Modeling Language are two state-of-the-art conceptual modeling languages. While both languages aim at the same purpose of providing a means for general-purpose systems engineering, these languages take different approaches in realizing this goal. As each of the languages has its relative strengths and weaknesses, ways to create synergies between them are considered in this work. We propose combining advantages of each language through automatic generation of SysML views from an OPM model. To this end, we developed a new algorithm and software application implementing the OPM-to-SysML views generation. Our approach can benefit various stakeholders by promoting better system understanding, standardization, and improved interoperability.
New secure channel coding scheme based on randomly punctured quasi-cyclic-low density parity check codes

A new joint cryptography-channel coding technique is introduced which employs punctured quasi-cyclic-low density parity check (QC-LDPC) codes obtained from extended difference families. The absence of permutation and scrambling matrices reduces the key size compared with similar code-based cryptosystems, while having an acceptable level of security. The main advantage of this system is that, provided the system parameters are chosen appropriately, even if the code employed is revealed the system remains secure. Performance results are presented which show that the punctured code outperforms a random low density parity check (LDPC) code of the same length and rate.
Application of different models to the lactation curves of unimproved Awassi ewes in Turkey

The objective of this study was to investigate the use of four different mathematical functions (Wood, Inverse Polynomial, Quadratic and Cubic models) for describing the lactation curve of unimproved Awassi ewes. Data were collected from 136 ewes from the same flock raised on the State Farm of Gozlu in the Konya Province of Turkey. The differences in estimated total milk yields between the models were not statistically significant. All models were adequate in describing total milk yield, though total milk yield estimated using the Cubic model was very close to total milk yield calculated by the Fleischmann method. Age effects on model parameters were not significant. The Inverse Polynomial model overestimated the peak yield significantly. Estimated peak yields of the Wood and Cubic model were similar while that obtained from the Quadratic model was significantly lower than that of the other models. Day of peak yield estimated by the models varied between 10.2 and 56.4 days. The differences between days of peak yield estimated using the different models were significant. R2 values of the models ranged from 0.724 to 0.977. The Cubic model gave the best R2 value. The lowest mean square prediction error was found using the Cubic model. Correlation coefficients between total milk yield calculated by the Fleischmann method and estimated total milk yield from the other models ranged from 0.933 to 0.998. The highest correlation coefficient was found for the Cubic model. As a result, the Cubic model showed the best fit to the data collected from unimproved Awassi ewes and allowed a suitable description of the shape of the lactation curve. South African Journal of Animal Science Vol. 35(4) 2005: 238-243
Immune mechanisms in epileptogenesis

Epilepsy is a chronic brain disorder that affects 1% of the human population worldwide. Immune responses are implicated in seizure induction and the development of epilepsy. Pre-clinical and clinical evidence have accumulated to suggest a positive feedback cycle between brain inflammation and epileptogenesis. Prolonged or recurrent seizures and brain injuries lead to upregulation of proinflammatory cytokines and activated immune responses to further increase seizure susceptibility, promote neuronal excitability, and induce blood–brain barrier breakdown. This review focuses on the potential role of innate and adaptive immune responses in the pathogenesis of epilepsy. Both human studies and animal models that help delineate the contributions of brain inflammation in epileptogenesis will be discussed. We highlight the critical role of brain-resident immune mediators and emphasize the contribution of brain-infiltrating peripheral leukocytes. Additionally, we propose possible immune mechanisms that underlie epileptogenesis. Several proinflammatory pathways are discussed, including the interleukin-1 receptor/toll-like receptor signaling cascade, the pathways activated by damage-associated molecular patterns, and the cyclooxygenase-2/prostaglandin pathway. Finally, development of better therapies that target the key constituents and processes identified in these mechanisms are considered, for instance, engineering antagonizing agents that effectively block these pathways in an antigen-specific manner.
Carbon burning in intermediate-mass primordial stars

The evolution of a zero metallicity 9 Mstar is computed, analyzed and compared with that of a solar metallicity star of identical ZAMS mass. Our computations range from the main sequence until the formation of a massive oxygen-neon white dwarf. Special attention has been payed to carbon burning in conditions of partial degeneracy as well as to the subsequent thermally pulsing Super-AGB phase. The latter develops in a fashion very similar to that of a solar metallicity 9 Mstar, as a consequence of the significant enrichment in metals of the stellar envelope that ensues due to the so-called third dredge-up episode. The abundances in mass of the main isotopes in the final ONe core resulting from the evolution are X( 16 O) ≈ 0.59, X( 20 Ne) ≈ 0.28 and X( 24 Mg) ≈ 0.05. This core is surrounded by a 0.05 Mbuffer mainly composed of carbon and oxygen, and on top of it a He envelope of mass ∼10 −4 M� .
Carbohydrate metabolism during intense exercise when hyperglycemic.

The effects of hyperglycemia on muscle glycogen use and carbohydrate metabolism were evaluated in eight well-trained cyclists (average maximal O2 consumption 4.5 +/- 0.1 l/min) during 2 h of exercise at 73 +/- 2% of maximal O2 consumption. During the control trial (CT), plasma glucose concentration averaged 4.2 +/- 0.2 mM and plasma insulin remained between 6 and 9 microU/ml. During the hyperglycemic trial (HT), 20 g of glucose were infused intravenously after 8 min of exercise, after which a variable-rate infusion of 18% glucose was used to maintain plasma glucose at 10.8 +/- 0.4 mM throughout exercise. Plasma insulin remained low during the 1st h of HT, yet it increased significantly (to 16-24 microU/ml; P less than 0.05) during the 2nd h. The amount of muscle glycogen utilized in the vastus lateralis during exercise was similar during HT and CT (75 +/- 8 and 76 +/- 7 mmol/kg, respectively). As exercise duration increased, carbohydrate oxidation declined during CT but increased during HT. Consequently, after 2 h of exercise, carbohydrate oxidation was 40% higher during HT than during CT (P less than 0.01). The rate of glucose infusion required to maintain hyperglycemia (10 mM) remained very stable at 1.6 +/- 0.1 g/min during the 1st h. However, during the 2nd h of exercise, the rate of glucose infusion increased (P less than 0.01) to 2.6 +/- 0.1 g/min (37 mg.kg body wt-1.min-1) during the final 20 min of exercise. We conclude that hyperglycemia (i.e., 10 mM) in humans does not alter muscle glycogen use during 2 h of intense cycling. (ABSTRACT TRUNCATED AT 250 WORDS)
Errata

In this paper we report the regulation of Aspergillus niger growth rate during citric acid fermentation in a stirred tank bioreactor. For this, the influence of dissolved oxygen concentration in a medium on intracellular pH values and consequently on overall microbial metabolism was emphasized. Intracellular pH of mycelium grown under different concentrations of dissolved oxygen in the medium was determined. Sensitivity of proteins toward proton concentration is well recognized, therefore pH influences on the activities of key regulatory enzymes of Aspergillus niger were determined at pH values similar to those detected in the cells grown under lower dissolved oxygen concentrations. The results have shown significantly reduced specific activities of hexokinase, 6-phosphofructokinase and glucose-6-phosphate dehydrogenase in more acidic environment, while pyruvate kinase was found to be relatively insensitive towards higher proton concentration. As expected, due to the reduced specific activities of regulatory enzymes under more acidic conditions, overall metabolism should be hindered in the medium with lower dissolved oxygen concentration which was confirmed by detecting the reduced specific growth rates. From the studies, we conclude that dissolved oxygen concentration affects the intracellular pH and thus growth rate of Aspergillus niger during the fermentation process.