Miracle-dz/UniFAR-FTUs huggingface dataset:
On the Optimal Control of Two Queues with Server Setup Times and its Analysis

Two queues are fed by independent, time-homogeneous Poisson arrival processes. One server is available to handle both. All service durations, in both queues, are drawn independently from the same distribution. A setup time is incurred whenever the server moves (switches) from one queue to the other. We prove that in order to minimize the sum of discounted setup charges and holdings costs, assumed linear in queue length and having the same rate at the two queues, the service at each queue should be exhaustive, A “threshold policy” is defined as a policy under which the server switches (from an empty queue) only when the other reaches a critical size. It is shown to be a likely candidate for the optimal policy, both for the discounted version and for the long-time average criterion.The steady-state performance of this policy (under somewhat more general distributional assumptions) and the optimal thresholds are determined for a number of cases.
COPD and its comorbidities: Impact, measurement and mechanisms

Chronic obstructive pulmonary disease (COPD) frequently coexists with other conditions often known as comorbidities. The prevalence of most of the common comorbid conditions that accompany COPD has been widely reported. It is also recognized that comorbidities have significant health and economic consequences. Nevertheless, there is scant research examining how comorbidities should be assessed and managed in the context of COPD. Also, the underlying mechanisms linking COPD with its comorbidities are still not fully understood. Owing to these knowledge gaps, current disease‐specific approaches provide clinicians with little guidance in terms of managing comorbid conditions in the clinical care of multi‐diseased COPD patients. This review discusses the concepts of comorbidity and multi‐morbidity in COPD in relation to the overall clinical outcome of COPD management. It also summarizes some of the currently available clinical scores used to measure comorbid conditions and their prognostic abilities. Furthermore, recent developments in the proposed mechanisms linking COPD with its comorbidities are discussed.
Native prion protein homodimers are destabilized by oligomeric amyloid &bgr; 1–42 species as shown by single-molecule imaging

Prion proteins (PrPc) are receptors for amyloid &bgr; 1–42 (A&bgr;1–42) oligomers, but we do not know the impact of A&bgr;1–42 binding to PrPc on the interaction of membrane-bound PrPc with molecules that regulate downstream biological pathways. Stability of the PrPc dimeric complex and subsequent intermolecular interactions with membranous or cytoplasmic molecules are important for physiological functions of PrPc including neuroprotection. The principal aim of this study was to determine whether homodimer lifetime of PrPc is affected by the presence of A&bgr;1–42 oligomers. Single-molecule imaging analysis was carried out by total internal reflection fluorescence microscopy in PrPc-transfected CHO-K1 cells in the absence or presence of characterized A&bgr;1–42 oligomers. The contribution of different A&bgr;1–42 oligomer conformations to Alzheimer’s disease pathophysiology and to the associated neurotoxicity is unknown. To be precise, with the oligomeric species used in our study, we biochemically analyzed the molecular weight of oligomers formed from A&bgr;1–42 monomers under our experimental conditions. The lifetime of PrPc homodimers was 210 ms, and in the presence of A&bgr;1–42 oligomers, the lifetime was significantly reduced (to 92 ms). The reduction of PrPc homodimer lifetime by A&bgr;1–42 oligomers may impair PrPc-mediated downstream neuroprotective signaling.
Activation of Xenopus Genes Required for Lateral Inhibition and Neuronal Differentiation during Primary Neurogenesis

XNGN-1, a member of the neurogenin family of basic helix-loop-helix proteins, plays a critical role in promoting neuronal differentiation in Xenopus embryos. When ectopically expressed, XNGN-1 induces the expression of a set of genes required for neuronal differentiation such as XMyT1 and NeuroD. At the same time, however, XNGN-1 induces the expression of genes that antagonize neuronal differentiation by a process called lateral inhibition. Here, we present evidence that XNGN-1 activates the expression of genes required for differentiation and lateral inhibition by recruiting transcriptional coactivators p300/CBP (CREB-binding protein) or PCAF (p3OO/CBP-associated protein), both of which contain histone acetyltransferase (HAT) activity. Significantly, transcriptional activation of the genes in the lateral inhibitory pathway is less dependent on the HAT activity than is the activation of the genes that mediate differentiation. We propose that this difference enables the genes in the lateral inhibition pathway to be induced prior to the genes that promote differentiation, thus enabling lateral inhibition to establish a negative feedback loop and restrict the number of cells undergoing neuronal differentiation.
Probing growth-related disorder by high-field transport in semiconductor superlattices.

We investigate the influence of imperfections in the sample growth on the electrical transport in doped superlattices. While structurally perfect samples should exhibit a regular set of current branches, our theoretical investigations show that local fluctuations of the sample parameters in the growth direction strongly modulate the branches of the current-voltage characteristic. A comparison with experimental data allows an estimate of the range of doping fluctuations between 3% and 10%. The disorder strongly affects the frequency as well as the mode of the self-oscillations of the current.
Complex permittivity and moisture measurements of oil palm fruits using an open-ended coaxial sensor

An open-ended coaxial sensor for the determination of complex permittivity and moisture content of oil palm fruits is presented in this paper. The measurement system consisting of the sensor and a PC-controlled vector network analyzer have been tested successfully on a range of oil palm fruits of various degrees of ripeness. The initial values of the complex permittivity were estimated using the admittance model of the sensor. The amount of moisture content was found by matching the values of permittivity from the quasistatic model with the permittivity of a dielectric mixture model using the moisture content values obtained from the standard oven drying method.
Fro luorescence spectroscopy for the detection of tongue arcinoma — validation in an animal model ristina

anderlei S. Bagnato niversidade de São Paulo nstituto de Física de São Carlos venida Trabalhador Sancarlense, 400 Centro 3566-250, São Carlos, São Paulo razil Abstract. The efficacy of fluorescence spectroscopy to detect squamous cell carcinoma is evaluated in an animal model following laser excitation at 442 and 532 nm. Lesions are chemically induced with a topical DMBA application at the left lateral tongue of Golden Syrian hamsters. The animals are investigated every 2 weeks after the 4th week of induction until a total of 26 weeks. The right lateral tongue of each animal is considered as a control site normal contralateral tissue and the induced lesions are analyzed as a set of points covering the entire clinically detectable area. Based on fluorescence spectral differences, four indices are determined to discriminate normal and carcinoma tissues, based on intraspectral analysis. The spectral data are also analyzed using a multivariate data analysis and the results are compared with histology as the diagnostic gold standard. The best result achieved is for blue excitation using the KNN K-nearest neighbor, a interspectral analysis algorithm with a sensitivity of 95.7% and a specificity of 91.6%. These high indices indicate that fluorescence spectroscopy may constitute a fast noninvasive auxiliary tool for diagnostic of cancer within the oral cavity. © 2008 Society of Photo-Optical Instrumentation Engineers. DOI: 10.1117/1.2937214
The contact activation and kallikrein/kinin systems: pathophysiologic and physiologic activities

The contact activation system (CAS) and kallikrein/kinin system (KKS) are older recognized biochemical pathways that include several proteins that skirt the fringes of the blood coagulation, fibrinolytic, complement and renin‐angiotensin fields. These proteins initially were proposed as part of the hemostatic pathways because their deficiencies are associated with prolonged clinical assays. However, the absence of bleeding states with deficiencies of factor XII (FXII), prekallikrein (PK) and high‐molecular‐weight kininogen indicates that the CAS and KKS do not contribute to hemostasis. Since the discovery of the Hageman factor 60 years ago much has been learned about the biochemistry, cell biology and animal physiology of these proteins. The CAS is a pathophysiologic surface defense mechanism against foreign proteins, organisms and artificial materials. The KKS is an inflammatory response mechanism. Targeting their activation through FXIIa or plasma kallikrein inhibition when blood interacts with the artificial surfaces of modern interventional medicine or in acute attacks of hereditary angioedema restores vascular homeostasis. FXII/FXIIa and products that arise with PK deficiency also offer novel ways to reduce arterial and venous thrombosis without an effect on hemostasis. In summary, there is revived interest in the CAS and KKS due to better understanding of their activities. The new appreciation of these systems will lead to several new therapies for a variety of medical disorders.
Making Sense of the Links: Professional Development, Teacher Practices, and Student Achievement

Background/Context Although there is substantial evidence that high-quality professional development can improve teacher practices, less evidence exists for the effects of teacher professional development on intermediate outcomes, such as teacher practices, and their ultimate effects on K–12 student achievement. This work links professional development through teacher practices to examine their separate and combined effects on student achievement. Research Questions When teacher characteristics and teacher preparation program are controlled, what are the effects of teacher professional development on (1) teacher practices in mathematics and reading, and (2) subsequent student mathematics and reading achievement? Population The study uses students (n = 1,550–6,408) nested within teachers (n = 168–1,029) from six existing databases, two from the 2000 Beginning Teacher Preparation Survey conducted in Connecticut and Tennessee, and four from the National Assessment of Educational Progress (NAEP Mathematics 1996, 2000, and NAEP Reading 1998, 2000). Research Design This quantitative study employed a hybrid structural equation model built based on relationships indicated by the literature. Using extant large-scale data sets, the model was first tested using the smallest data set and then confirmed using successively larger state and national data sets. Conclusions Professional development has moderate effects on teacher practice and very small but sometimes significant effects on student achievement when the effects of professional development are mediated by teacher practice. In spite of differences in samples, academic subjects, and assessments, the effects of professional development on teacher practice and student achievement persist and are remarkably similar across analyses.
Comparison of readout-segmented echo-planar imaging (EPI) and single-shot EPI in clinical application of diffusion-weighted imaging of the pediatric brain.

OBJECTIVE Readout-segmented echo-planar imaging (EPI) has been suggested as an alternative to single-shot EPI for diffusion-weighted imaging (DWI) with reduced distortion. However, clinical comparisons of readout-segmented EPI and EPI DWI are limited by unmatched imaging parameters and reconstruction procedures. Our goal was to compare the clinical utility of generalized autocalibrating partial parallel acquisition (GRAPPA)-accelerated readout-segmented EPI DWI with GRAPPA-accelerated EPI DWI for visualization of the pediatric brain in regions prone to distortion, such as the orbit, skull base, and posterior fossa. SUBJECTS AND METHODS Thirty consecutive patients (mean age, 7.8 years) presenting with orbital, skull base, and posterior fossa neuropathologic abnormalities were scanned at 3 T. Images were obtained using GRAPPA-accelerated readout-segmented EPI and GRAPPA-accelerated EPI with an identical scanning time, acceleration factor, target resolution, and image postprocessing procedure. The two datasets were independently reviewed by two blinded neuroradiologists. Imaging studies were evaluated for resolution, signal-to-noise ratio (SNR), contrast, distortion, lesion conspicuity, and diagnostic confidence and graded using a 7-point Likert scale (1, nondiagnostic; 7, outstanding). RESULTS There was good reader agreement in the scores (κ = 0.66; 95% CI, 0.54-0.78). The mean scores for EPI and readout-segmented EPI, respectively, were as follows: resolution, 5.0 and 6.0; SNR, 5.5 and 3.0; contrast, 3.7 and 3.2; distortion, 4.8 and 6.0; lesion conspicuity, 4.6 and 5.1; and diagnostic confidence, 4.7 and 5.4. Readout-segmented EPI was superior in resolution, distortion reduction, lesion conspicuity, and diagnostic confidence, whereas EPI scored better in SNR and contrast. Readout-segmented EPI was considered the better sequence overall in 85% of the cases. CONCLUSION This study shows the benefits of improved resolution and reduced distortion of readout-segmented EPI in evaluating the orbit, skull base, and posterior fossa, sites of common neuropathologic abnormalities in children.
Robot Planning with Ant Colony Optimization Algorithms

Ant colony optimization algorithms are investigated in this paper for robot planning in configuration space. The robot planning problem is to find a feasible path from a beginning to a goal while avoiding obstacles in a clustered environment. Lots of attentions have been paid on such problems, but little is with the ant colony optimization algorithms. Originated from the max-min ant system (MMAS) algorithm for traveling salesman problem, a modified ant colony optimization algorithm for robot planning is proposed. The algorithm has some distinguished features, such as a path pruning mechanism, etc. The optimal solution can be achieved effectively in different environments with a high probability.
Semilunar Coronally Advanced Flap with or without Low Level Laser Therapy in Treatment of Human Maxillary Multiple Adjacent Facial Gingival Recessions: A Clinical Study.

PURPOSE Semilunar coronally advanced flap (SCAF) and its modifications or adjuncts have been proposed in the literature for root coverage. Low level laser therapy (LLLT) has been shown to enhance wound healing. The aim of this split-mouth randomized controlled clinical trial was to assess the effects of LLLT application with respect to root coverage after SCAF procedure for the treatment of human maxillary multiple adjacent facial gingival recessions. MATERIALS AND METHODS Ten subjects with bilateral multiple adjacent maxillary facial gingival recession defects (Miller I and II) were included in this study (20 in test, 20 in control group). A diode laser (810 nm) at 0.3 watts was applied to test sites during and 1 week after surgery for 10 seconds. Comparisons of the surgical sites were made with clinical measurements. RESULTS Statistically significant differences were observed between test and control sites in the change in gingival recession depth, gingival recession width, clinical attachment level, and width of the keratinized tissue measurements after 6 months (p = 0.003, p = 0.001, p = 0.006, and p =< 0.001, respectively). The test group presented significantly greater complete root coverage (N = 18/20, 90%) compared with the control group (N = 6/20, 30%) at 6 months post-operatively. CONCLUSION Within the confines of this study, the results depicted that a Low Level Laser Technique application may enhance the predictability of SCAF procedure. Further long-term studies with more sample sizes are needed for a stronger evidence base. CLINICAL SIGNIFICANCE Gingival recessions are commonly encountered in dentistry and pose an esthetic concern. Minimal gingival recessions can be treated by a Semilunar Coronally Advanced Flap (SCAF), but the predictability and stability of the outcomes are quiet questionable. In the present report, a Low Level Laser Technique (LLLT) application adjunct to SCAF depicted a significant improvement in the predictability and stability of root coverage outcomes (for a period of 6 months) compared with as achieved by SCAF alone. From this report, it can be stated that LLLT may be effectively used in a day to day practice for enhancing the root coverage outcomes of SCAF.
The Response of Renal Tubular Epithelial Cells to Physiologically and Chemically Induced Growth Arrest*

Cells respond to a variety of stresses by activating the transcription of a battery of “acute phase” or “stress response” genes. The nature of this response is tailored to the nature of the stress. The extent to which physiologically and pathophysiologically induced growth arrest share common genomic responses is unclear. We therefore compared the effects of a physiologically induced (serum and nutrient depletion) and a chemically induced (2-Br-bis-(GSyl)HQ and 2-Br-6-(GSyl)HQ) stress in renal tubular epithelial cells (LLC-PK1). The response to physiological stress, induced by serum depletion, involves growth arrest characterized by an inhibition of DNA synthesis that occurs in the absence of a decrease in histone mRNA or an increase in gadd153 mRNA, one of the growth arrest and DNA damage inducible genes. In contrast, the chemical-induced stress involves growth arrest accompanied by a decrease in histone mRNA, particularly core histone H2B and H2A mRNA, and the induction of gadd153 Chemical-induced changes in histone mRNA inversely correlate to changes in the expression of a stress gene, hsp70, whose expression is dependent upon the maintenance of appropriate nucleosomal structure.
Reproductive health in women with systemic lupus erythematosus compared to population controls

Objective: To study the reproductive health history in women with systemic lupus erythematosus (SLE) compared to population controls. Methods: A total of 206 female SLE patients were interviewed regarding demographic and disease data, menstruation, use of contraception and hormone replacement therapy (HRT), infertility, and pregnancies. The control group consisted of 1037 women from the general population of similar age and socioeconomic status living in the same region. Results: In SLE women compared to population controls, mean age at menarche (13.3 vs. 13.2 years) and frequency of infertility (16% vs. 16%) were similar but menopause occurred earlier (44.9 vs. 46.8 years, p = 0.01). Current use of oral contraceptives (OCs) was less common than in controls [18% vs. 28%, odds ratio (OR) 0.55, 95% CI 0.3–1.0] while previous use of progesterone-containing intrauterine devices (IUDs) was more common (13% vs. 5%, OR 3.2, 95% CI 1.9–5.4). Current use of HRT was similar (22% vs. 21%) but SLE patients had started the use earlier (43.2 vs. 47.1 years, p = 0.003). Mean number of pregnancies was lower in SLE patients compared to controls (2.3 vs. 2.5, p = 0.046) and in lupus nephritis patients compared to SLE patients without nephritis (1.9 vs. 2.5, p = 0.01). No difference was found in the occurrence of spontaneous and induced abortions compared to controls, but pregnancy-associated complications were more common in SLE women. Conclusion: When compared to population controls women with SLE are normally fertile, use less OCs and more IUDs, have earlier menopause and use HRT as frequently. Family size is reduced, especially in lupus nephritis patients, and pregnancy-associated complications are more common.
Heparinase I from Flavobacterium heparinum

In this study we have identified the primary heparin binding site of heparinase I (EC 4.2.2.7). Chemical and proteolytic digests of heparinase I were used in direct binding and competition assays, to map the regions of heparinase I that interact specifically with heparin. We find the heparin binding site contains two Cardin-Weintraub heparin binding consensus sequences and a calcium co-ordination consensus motif. We show that heparin binding to heparinase I is independent of calcium (K of 60 nM) and that calcium is able to activate heparinase I catalytically. We find that sulfhydryl selective labeling of cysteine 135 of heparinase I protects the lysines of the heparin binding sequence from proteolytic cleavage, suggesting the close proximity of the heparin binding site to the active site. Site-directed mutagenesis of H203A (contained in the heparin binding site) inactivated heparinase I; however, a H203D mutant retained marginal activity, indicating a role for this residue in catalysis. The above results taken together suggest that histidine 203 (hence the heparin binding site) is immediately adjacent to the scissile bond. We propose that the heparin binding site and active site are in close proximity to each other and that the calcium coordination motif, contained in the heparin binding site, may bridge heparin to heparinase I through calcium in a ternary complex during catalysis.
Intrinsic Macrolide Resistance of the Mycobacterium tuberculosis Complex Is Inducible

ABSTRACT Mycobacterium tuberculosis is intrinsically resistant to macrolides, a characteristic associated with expression of the erm(37) gene. This intrinsic resistance was found to be inducible with clarithromycin and the ketolide HMR3004. Furthermore, underlying the phenotypic induction was an increase in erm(37) mRNA levels.
Targeted Knockdown of EGR-1 Inhibits IL-8 Production and IL-8-mediated Invasion of Prostate Cancer Cells through Suppressing EGR-1/NF-κB Synergy*

IL-8 produced by prostate cancer cells may be responsible for the androgen-independent growth of advanced prostate cancers. Accumulating evidence from microarray analyses and animal genetic models highlights the central involvement of the transcription factor early growth response-1 (EGR-1) in prostate carcinoma progression. It is unknown, however, whether knockdown of EGR-1 inhibits IL-8 production and IL-8-mediated tumor metastasis. Here we show that EGR-1 knockdown by a specific shRNA-Egr1 inhibited gene transcription and production of IL-8 by the human prostate cancer cell line DU145. Conversely, enforced expression of EGR-1 in EGR-1-lacking PC3 prostate cancer cells markedly enhanced IL-8 transcription and secretion. By using wild type and a series of mutant IL-8 promoter luciferase constructs, we found that the NF-κB binding site is important for EGR-1 regulation of IL-8. Furthermore, silencing EGR-1 suppressed a synergistically functional interaction between EGR-1 and NF-κB. Consequently, knockdown of EGR-1 inhibited IL-8-mediated tumor colony formation and invasion. Thus, targeted knockdown of EGR-1 could be an effective therapeutic approach against prostate cancer.