Miracle-dz/UniFAR-FTUs huggingface dataset:
Miniaturized Bridgeless High-Frequency Resonant AC–DC Step-Up/Step-Down Converters

This paper introduces two bridgeless resonant ac-to-dc converters to efficiently convert arbitrary input voltages into a regulated dc output voltage. The proposed topologies provide direct ac-dc power conversion with less number of components, in comparison to other resonant topologies. The converters utilize soft-switched LC networks and diodes to convert low-frequency and low-amplitude alternating input voltage into a dc output voltage. Zero-voltage switching (ZVS) and zero-current switching (ZCS) are achieved in switching both power transistors and diodes. High-frequency soft-switching operation due to LC resonance allows smaller footprint for passive components, thereby increasing the circuit power density without suffering from switching losses. A resonant gate drive circuit is designed and utilized to further reduce gating losses under high-frequency switching and light-load condition. The converters operate at a fixed switching frequency, while they regulate the output voltage by using module pulsewidth-modulated (PWM) on-off control with fast transient response. A 5-mm × 6-mm, 100-mg prototype is fabricated, which is operating at 2-MHz switching frequency. The maximum output power of the prototype reaches 650 mW, with a 3- Vrms ac input voltage and a 7.6-V dc output voltage. The converter achieves higher than 70% closed-loop efficiency across wide range of input voltages and output powers.
Prevalence and Clinical Relevance of cagA, vacA, and iceA Genotypes of Helicobacter pylori Isolated From Slovenian Children

Background:Although infection with Helicobacter pylori in children mostly induces asymptomatic chronic gastritis, the clinical outcome of H pylori infection is generally unpredictable. To identify the risk subgroup of infected children who can progress toward serious gastrointestinal disease, we assessed the prevalence of H pylori virulence genes cagA, vacA, and iceA in children from southeastern Europe and correlated their presence with the severity of histological changes in the stomach. Materials and Methods:A total of 165 children (age range 4–18 years, mean 13 years) with H pylori infection were studied for a 6-year period. Virulence genes were determined by polymerase chain reaction from biopsy samples. Results:The cagA gene was present in 61.2% of patients. The predominant vacA genotype was s1m1 (42%), followed by s1m2 (28%), and s2m2 (24%). IceA genotypes iceA1 and iceA2 were detected in 62% and 31% of the samples, respectively. Multiple genotypes were found in 11.5% of isolates. The H pylori density score, the degree of chronic and acute inflammation, correlated with a cagA-positive status (P < 0.01, P < 0.01, P = 0.01, respectively). Higher bacterial infiltration (P < 0.01) and degree of chronic inflammation (P = 0.03) were detected in vacA s1–positive samples. Conclusion:CagA, vacA s1m1, and iceA1 genotypes are the predominant genotypes of H pylori isolated from the southeastern European pediatric population. CagA and vacA s1 are important virulence determinants of H pylori in children, but were not found associated with an increased incidence of precancerous gastric lesions.
Association between serum albumin and mortality in dialysis patients is partly explained by inflammation, and not by malnutrition.

OBJECTIVE We investigated the effects of inflammatory and nutritional status on the association between serum albumin and mortality in hemodialysis (HD) and peritoneal dialysis (PD) patients. DESIGN AND PATIENTS This was a prospective cohort study of incident dialysis patients starting HD or PD. Inflammation (C-reactive protein >or=5 or >or=10 mg/L), malnutrition (1 to 5 on the 7-point subjective global assessment [SGA]), and low protein intake (normalized protein equivalent of nitrogen appearance [nPNA] <0.99 g/kg/day) were measured at 3 months after the start of dialysis. SETTING The study involved 38 dialysis centers in The Netherlands. MAIN OUTCOME MEASURE We ascertained all-cause mortality during the first 2 years after the start of dialysis. RESULTS In total, 700 patients were included (mean SD age, 59 [+/-15] years; serum albumin, 3.3 (0.7) g/dL; 60% men; 454 starting HD, and 246 starting PD). The 2-year mortality was 21%. In HD patients, the mortality (hazard ratio [HR], with 95% confidence interval [95% CI]) per unit decrease in serum albumin (g/dL) was 1.47 (95% CI, 1.07 to 2.00). Adjustment for SGA did not decrease this risk, whereas adjustment for nPNA decreased the HR to 1.45 (95% CI, 1.06 to 1.97). The mortality risk decreased to 1.30 (95% CI, 0.95 to 1.78) after adjustment for inflammation, and did not further decrease after additional adjustment for SGA and nPNA. Additional adjustments for age, sex, and comorbidity decreased the HR to 1.09 (95% CI, 0.79 to 1.51). In PD patients, the effects of adjustments on the mortality risk of serum albumin (1.38; 95% CI, 0.87 to 2.20) were similar. CONCLUSION In dialysis patients, a 1-g/dL decrease in serum albumin was associated with an increased mortality risk of 47% in HD patients and 38% in PD patients. These mortality risks were in part explained by the inflammatory pathway. The mortality risks associated with serum albumin were not a consequence of malnutrition, as measured with SGA and nPNA. These findings imply that nutritional status cannot be assessed with precision by the measurement of serum albumin in dialysis patients.
Molecular characterization and analysis of the biosynthetic gene cluster for the azoxy antibiotic valanimycin

Streptomyces viridifaciens MG456‐hF10 produces the antibiotic valanimycin, a naturally occurring azoxy compound. Valanimycin is known to be derived from valine and serine with the intermediacy of isobutylamine and isobutylhydroxylamine, but little is known about the stages in the pathway leading to the formation of the azoxy group. In previous studies, a cosmid containing S. viridifaciens DNA was isolated that conferred valanimycin production upon Strepto‐myces lividans TK24. Subcloning of DNA from the valanimycin‐producing cosmid has led to the identi‐fication of a 22 kb segment of DNA sufficient to allow valanimycin production in S. lividans TK24. Sequencing of this DNA segment and the surrounding DNA revealed the presence of 20 genes. Gene disruption experiments defined the boundaries of the valanimycin gene cluster, which appears to contain 14 genes. The cluster includes an amino acid decar‐boxylase gene ( vlmD ), a valanimycin resistance gene ( vlmF ), at least two regulatory genes ( vlmE , vlmI ), two genes encoding a flavin monooxygenase ( vlmH , vlmR ), a seryl tRNA synthetase gene ( vlmL ) and seven genes of unknown function. Overproduction and characterization of VlmD demonstrated that it catalyses the decarboxylation of l ‐valine. An unusual feature of the valanimycin gene cluster is that four genes involved in branched amino acid biosynthesis are located near its 5′ end.
Thalidomide neurotoxicity

The authors prospectively followed 14 patients treated with thalidomide for cutaneous lupus erythematosus (CLE), in order to evaluate the occurrence of peripheral neuropathy (PN) and to assess whether PN correlates with thalidomide dose. The patients were followed for up to 24 months with neurologic and electrophysiologic evaluations. Seven patients (50%) developed sensory axonal PN. The median time free from PN was 14 months. PN occurred after 10 months in the majority of patients. No correlations were found between thalidomide cumulative dose and occurrence of PN (Mann-Whitney U test; p > 0.16).
Preliminary results on tunable Frequency Selective Surface for beam steering transmit-array applications

In this paper, first results from a study on the employment of Frequency Selective Surfaces (FSSs) for beam steering transmitarray applications are presented. The basic idea of the proposed research, it to use FSS for controlling the transmission properties of an electromagnetic wave propagating through a FSS. As it will be shown, it will be possible to achieve full control of the transmission angle across the FSS surface without affecting the signal amplitude.
XRCC1 genetic polymorphism Arg399Gln and gastric cancer risk: A meta-analysis.

AIM To evaluate the association between X-ray cross-complementing gene 1 (XRCC1) genetic polymorphism Arg399Gln and gastric cancer risk by means of meta-analysis. METHODS We searched PubMed and NCBI up to June 1, 2008. A total of 16 clinical trials and reports were identified, but only 8 trials qualified under our selection criteria. Statistical analysis was performed with the software program Review Manage, version 4.2. 8. RESULTS Of the 8 case-control studies selected for this meta-analysis, a total of 1334 gastric cancer cases and 2194 controls were included. For Arg399Gln, the Gln/Gln genotype carriers did not have a decreased cancer risk compared with those individuals with the Arg/Arg genotype (OR = 0.92, 95% CI, 0.71-1.19; P = 0.51). Similarly, no associations were found in the recessive and dominant modeling (Gln/Gln vs Arg/Gln + Arg/Arg: OR = 0.96; 95% CI, 0.77-1.19; P = 0.70 and Gln/Gln + Arg/Gln vs Arg/Arg: OR = 0.90, 95% CI, 0.77-1.05; P = 0.18). CONCLUSION No association is found between the XRCC1 polymorphism Arg399Gln and gastric cancer risk.
Neonatal Meningitis: Overcoming Challenges in Diagnosis, Prognosis, and Treatment with Omics

Neonatal meningitis is a devastating condition. Prognosis has not improved in decades, despite the advent of improved antimicrobial therapy and heightened index of suspicion among clinicians caring for affected infants. One in ten infants die from meningitis, and up to half of survivors develop significant lifelong complications, including seizures, impaired hearing and vision, and delayed or arrested development of such basic skills as talking and walking. At present, it is not possible to predict which infants will suffer poor outcomes. Early treatment is critical to promote more favorable outcomes, though diagnosis of meningitis in infants is technically challenging, time-intensive, and invasive. Profound neuronal injury has long been described in the setting of neonatal meningitis, as has elevated levels of many pro- and anti-inflammatory cytokines. Mechanisms of the host immune response that drive clearance of the offending organism and underlie brain injury due to meningitis are not well understood, however. In this review, we will discuss challenges in diagnosis, prognosis, and treatment of neonatal meningitis. We will highlight transcriptomic, proteomic, and metabolomic data that contribute to suggested mechanisms of inflammation and brain injury in this setting with a view toward fruitful areas for future investigation.
The induction of chromosome aberrations in human lymphocytes by alpha-radiation.

Human blood has been irradiated with alpha-particles from an external source of curium-242. The collimated alpha-particles entered the blood with an energy of 4-9 MeV and were almost completely absorbed by the blood. After culturing for 48 hours, the dicentric yield in the lymphocytes at the first metaphase was measured as a function of dose to the blood. The yield was linear with dose up to 400 rad with a slope of 28x6 X 10(4) dicentrics/cell per rad. This is equivalent to an initial slope r.b. e. of 17x9 with respect to cobalt-60 gamma-rays. This value disagrees with the only two other published values in the literature. Reasons for this disagreement are discussed. Compared with neutron r.b. e values obtained in this laboratory the alpha-particle values we observe are surprisingly low. A model is proposed which predicts low values of r.b. e. for chromosome aberration production using radiations of high LET. The low values occur because there is a distribution of specific energy between cells which causes a selective removal of cells likely to contain higher numbers of aberrations.
Different Types of Cerebellar GABAergic Interneurons Originate from a Common Pool of Multipotent Progenitor Cells

Different cerebellar phenotypes are generated according to a precise spatiotemporal schedule, in which projection neurons precede local interneurons. Glutamatergic neurons develop from the rhombic lip, whereas GABAergic neurons originate from the ventricular neuroepithelium. Progenitors in these germinal layers are committed toward specific phenotypes already at early ontogenetic stages. GABAergic interneurons are thought to derive from a subset of ventricular zone cells, which migrate in the white matter and proliferate up to postnatal life. During this period, different interneuron categories are produced according to an inside-out sequence, from the deep nuclei to the molecular layer (we show here that nuclear interneurons are also born during late embryonic and early postnatal days, after glutamatergic and GABAergic projection neurons). To ask whether distinct interneuron phenotypes share common precursors or derive from multiple fate-restricted progenitors, we examined the behavior of embryonic and postnatal rat cerebellar cells heterotopically/heterochronically transplanted to syngenic hosts. In all conditions, donor cells achieved a high degree of integration in the cerebellar cortex and deep nuclei and acquired GABAergic interneuron phenotypes appropriate for the host age and engraftment site. Therefore, contrary to other cerebellar types, which derive from dedicated precursors, GABAergic interneurons are produced by a common pool of progenitors, which maintain their full developmental potentialities up to late ontogenetic stages and adopt mature identities in response to local instructive cues. In this way, the numbers and types of inhibitory interneurons can be set by spatiotemporally patterned signals to match the functional requirements of developing cerebellar circuits.
The In Vivo Response of Stem and Other Undifferentiated Spermatogonia to the Reversible Inhibition of Glial Cell Line‐Derived Neurotrophic Factor Signaling in the Adult

Maintaining adequate numbers of spermatogonial stem cells is required for the production of the millions of sperm required for male fertility. To date, however, the mechanisms that regulate the size of this pool in the adult are poorly defined. Glial cell line‐derived neurotrophic factor (GDNF) is required for establishing this pool in the prepubertal animal, but its in vivo function in the normal adult testis has never been examined directly. We used a chemical‐genetic approach to address this issue. We generated mice carrying a single amino acid mutation (V805A) in Ret, the kinase subunit of the GDNF receptor. This mutation does not affect normal GDNF signaling but renders it susceptible to inhibition by the ATP competitive inhibitor, NA‐PP1. When GDNF signaling was blocked in adults for 11 days, only a few cells remained that expressed the stem spermatogonial markers, Gfrα1 and Zbtb16, and testicular Ret mRNA content was reduced markedly. These decreases were associated with depletion of functional stem spermatogonia; some were lost when GDNF signaling was inhibited for only 2 days while others survived for up to 11 days. However, when signaling was restored, the remaining stem cells proliferated, initiating tissue restoration. In conclusion, these results provide the first direct proof that GDNF acutely regulates the number of spermatogonial stem cells in the normal adult testis. Additionally, these results demonstrate different sensitivities among subpopulation of these stem cells to inhibition of GDNF signaling. STEM CELLS 2012; 30:732–740
Was Shock Therapy Really a Shock?

The shock therapy model derived its name from Poland’s stabilization and liberalization program, initiated on January 1, 1990, which became known as “shock therapy” or “big bang. ” The countries that followed with the shock therapy approach were Czechoslovakia (starting January 1991), Bulgaria (February 1991), Russia (February 1992), Albania (July 1992), Estonia (September 1992), and Latvia (June 1993). In summary, the shock therapy model was a neoclassical model of transition advocating the immediate implementation of the necessary reforms to establish a free market economy. The shock therapy model of transition, the dominant model of transition, was attractive to transition governments, international financial institutions, and mature market economies due to its simplicity and narrow transition policies recommended. “Get prices right” and the remaining elements of a market capitalist system would, more or less, fall into place was an antithesis to an institutionalist approach to transition. The shock therapy approach abstracted from the more insightful and complicated institutionalist dimensions of the transition process. The transition process was characterized by uncertainty and the absence of any historical paradigms. Hence the Economist’s metaphor about the transition process was that there was no known recipe for unmaking an omelette (“No Halfway House” 1990, 18). Few economists attempted to approximate the initial conditions of centrally administered economies with the stabilization programs initiated in the mature market economies. For example, Jeffrey Sachs (1993, 3) argued “the prototypical case in Europe that I will refer to is that of Spain, which in many ways provides a kind of guidepost to the path that the economies of Eastern Europe should follow. ” Sebastian Edwards (1992, 131)
Relationship between short-acting β2-adrenergic agonist use and healthcare costs.

OBJECTIVE To assess whether increased short-acting β(2)-adrenergic agonist (SABA) claims are associated with asthma exacerbations and increased healthcare costs. STUDY DESIGN Cross-sectional study. METHODS Patients (N = 93,604) were health plan members aged 6-56 years with at least 2 years of enrollment between July 1, 2003, and June 30, 2007, an asthma diagnosis, and at least 1 asthma medication claim per study year. Two years of administrative claims were collected. SABA use was categorized as 0 (none), (1/2) to 2 (low), 2(1/2) to 6 (moderate), 6(1/2) to 12 (high), and more than 12 (excessive) canister equivalents per year. Multivariate analyses were adjusted for age, sex, geographic region, comorbidities, specialist consultation, controller medication use, and asthma severity. RESULTS Half of high and excessive SABA users had few or no controller claims. Compared with SABA nonusers, high and excessive SABA users had significantly higher odds (odds ratio [95% confidence interval]) of asthma-related emergency department/urgent care visits (6.47 [5.25, 7.98] and 7.68 [6.04, 9.76], respectively), hospitalizations (5.37 [6.04, 9.76]; 6.90 [4.90, 9.73]), and oral corticosteroid use (2.89 [2.72, 3.08]; 3.71 [3.41, 4.03]). Excessive SABA users had 3.0 times ($1791) and high SABA users had 2.2 times ($1326) higher asthma-related healthcare costs than low SABA users ($595). Total costs also increased with higher SABA use, but with smaller incremental differences between excessive and high SABA users and low SABA users. CONCLUSIONS Increased SABA use is associated with higher total and asthma-related healthcare costs. Opportunity exists to lessen overreliance on SABAs.
STRATEGIES FOR MANAGING SCHOLARLY CONTENT AT UNIVERSITIES IN KENYA

This study investigated strategies employed by universities in Kenya for managing scholarly content. The study was underpinned by the Conversation Theory and the Knowledge Management Process Model and was based on the post-positivist paradigm. A survey was conducted within a multiple case study design. The population of the study consisted of academic staff, postgraduate students, university librarians and representatives of university research units from six universities in Kenya. Self-administered questionnaires were used to collect data from academic staff and postgraduate students while key informants were interviewed. The results revealed that while the respondents generated theses, journal articles and conference papers, the majority did not participate in knowledge generation in the period from 2010 to 2014. The results further revealed that most respondents documented research procedures, backed up information, and used printouts to preserve scholarly content; however, they hardly used digital archives and university servers. The results suggested heavy reliance on modern technology-enabled communication techniques and faceto- face interactions for communication amongst scholars, whereas institutional repositories (IRs) were hardly used. The results revealed inadequate institutional support for research and scholarly communication including funding, material and physical infrastructure, mentorship, and information and communications technology (ICT) facilities. The study concluded that strategies for managing scholarly content at universities in Kenya are weak, impacting negatively on the quality, quantity and visibility of scholarly content; and that a policy framework encompassing the different facets of managing scholarly content is necessary. The study recommended developing specific strategies and policies to enhance scholarly content management; institutionalising mentorship programmes; increasing funding to strengthen universities' research capacity; and strengthening research niches.
Mesocestoides corti: parameters of infection in CBA/Ca mice and the effect of introducing a concomitant trematode infection

Summary CBA/Ca mice infected with the tetrathyridia of Mesocestoides corti were exposed to Schistosoma mansoni cercariae either simultaneously, or at varying intervals after the initial M. corti infection. Cohorts were infected with either parasite alone. The dual infected mice and the mice harbouring M. corti alone were significantly heavier than either naive controls or mice carrying the S. mansoni infection only. The livers and spleens from dual infection mice were also found to be significantly heavier than those from other groups. Free M. corti tetrathyridia were reduced in number in the peritoneal cavity of dual infected mice, as compared with mice harbouring a single infection. Furthermore, the intensity of the initial M. corti infection, as measured by the number of capsules surrounding parasites in the liver, was reduced when the mice experienced an S. mansoni infection 21 days later. The mice which were exposed to M. corti only exhibited more mast cells and eosinophils around encapsulated tetrathyridia in the liver than did dual infection mice, while cells surrounding S. mansoni egg granulomas in the liver were significantly increased in dual infection mice. An increase in serum alkaline phosphatase levels was detected in both the mice receiving the dual infection and the mice with the S. mansoni only infection, but not in mice harbouring M. corti alone.
Common sequence determinants of the response of a prokaryotic promoter to DNA bending and supercoiling.

Inhibiting the activity of DNA gyrase by mutation or by drugs in S. typhimurium causes the loss of transcription attenuation in the histidine operon. We show that gyrase activity is needed to maintain high‐level expression of the tRNA(His) gene (hisR), a prerequisite for proper functioning of the attenuation mechanism. A point mutation in the promoter of the tRNA gene cluster which includes the hisR gene, specifically relieves the promoter response to negative supercoiling thereby restoring full hisR transcription (and, in turn, his attenuation) in the presence of a defective gyrase. The very same mutation, a single base‐pair substitution between the ‐10 box and the transcription start site (‐7), was found independently among suppressors of the transcriptional deficiency caused by disruption of DNA curvature upstream from the hisR promoter. We show that the ‐7 change does not lead to a generalized increase of promoter strength; the effects of the mutation are seen only when gyrase is inhibited or the upstream curvature is altered. This suggests that the upstream curvature intervenes in the same initiation step which is sensitive to superhelical tension. Three additional promoter mutations correcting (or alleviating) the effects of the upstream alteration (including a change at ‐8) are described and discussed.