Miracle-dz/UniFAR-FTUs huggingface dataset:
What Determines Productivity?

Economists have shown that large and persistent differences in productivity levels across businesses are ubiquitous. This finding has shaped research agendas in a number of fields, including (but not limited to) macroeconomics, industrial organization, labor, and trade. This paper surveys and evaluates recent empirical work addressing the question of why businesses differ in their measured productivity levels. The causes are manifold, and differ depending on the particular setting. They include elements sourced in production practices--and therefore over which producers have some direct control, at least in theory--as well as from producers' external operating environments. After evaluating the current state of knowledge, I lay out what I see are the major questions that research in the area should address going forward.
Anti-Trust Rank: Fighting Web Spam

The Web is both an excellent medium for sharing information as well as an attractive platform for delivering products and services. This platform is, to some extent, mediated by search engines in order to meet the needs of users seeking information. Search engines are the “dragons” that keep a valuable treasure: information [8]. Given the vast amount of information available on the Web, it is customary to answer queries with only a small set of results (typically 10 or 15 pages at most). Search engines must then rank Web pages, in order to create a short list of highquality results for users. Web spam can significantly deteriorate the quality of search engine results. Thus there is a large incentive for commercial search engines to detect spam pages efficiently and accurately. Here we present the main techniques recently introduced for Web Spam detection.
Responses of GPCR135 to Human Gene 3 (H3) Relaxin in CHO‐K1 Cells Determined by Microphysiometry

Abstract: This study examined the functional response to human relaxin 2 (H2 relaxin), human relaxin 3 (H3 relaxin), porcine relaxin, and human INSL3 in the cytosensor microphysiometer, using CHO‐K1 cells stably expressing human GPCR135. CHO‐K1 cells stably expressing GPCR135 were generated by the serial dilution method and receptor properties were assessed. Saturation studies of [125I] H3 relaxin binding to GPCR135 in these cells gave a Bmax of 32.61 ± 6.5 fmol/mg protein and Kd of 0.12 ± 0.08 nM. The functional response to H3 relaxin and other relaxin/insulin peptides of GPCR135 expressed in CHO‐K1 cells was measured in the cytosensor microphysiometer and analyzed using inhibitors of signal transduction proteins.
NO alters cell shape and motility in aortic smooth muscle cells via protein tyrosine phosphatase 1B activation.

Cell motility is an important determinant of vascular disease. We examined mechanisms underlying the effect of nitric oxide (NO) on motility in cultured primary aortic smooth muscle cells from newborn rats. The NO donor S-nitroso- N-acetyl-penicillamine (SNAP) increased the activity of protein tyrosine phosphatase 1B (PTP-1B). This effect was mimicked by a cGMP analog and blocked by the guanyl cyclase antagonist 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, indicating the involvement of cGMP. Treatment of cells with antisense, but not control oligodeoxynucleotide (ODN), against PTP-1B attenuated the inhibitory effect of NO on cell motility. Cell shape and adhesion are important determinants of cell motility. We report that SNAP induced cell rounding and reduced adhesion and caused dissociation of actin stress fibers. Moreover, SNAP reduced phosphotyrosine levels in focal adhesion proteins, paxillin, and focal adhesion kinase. The PTP inhibitor phenylarsine oxide or decrease of PTP-1B protein levels via the use of antisense ODN prevented NO-induced cell-shape change, altered adhesion, and migration. These results indicate that NO regulates cell shape, adhesion, and migration by dephosphorylation of focal adhesion proteins via a mechanism that requires PTP-1B activity.
Epistatic Interactions Associated with Stevens–Johnson Syndrome

Abstract: Stevens–Johnson syndrome (SJS) is an acute inflammatory vesiculobullous reaction of the skin and mucosa, often including the ocular surface, and sometimes progresses to toxic epidermal necrolysis (TEN). SJS/TEN may be initiated by certain types of medication coupled with possible infection; however, few susceptibility genes have been identified as indicators for risk prediction, except for certain human leukocyte antigen alleles, although several candidate susceptibility genes were identified by candidate gene and genome-wide approaches. As an alternative genetic model, gene–gene interactions between candidate genes were investigated using high-dimensional variable selection methods such as iterative sure independence screening. Linkage disequilibria around the toll-like receptor (TLR)3 and prostaglandin E receptor (PTGER)3 genes were also investigated using additional single nucleotide polymorphisms in an extended additional sample set. A murine experimental allergic conjunctivitis (EAC) model was used to examine the functional interactions. Iterative sure independence screening analyses of Japanese SJS/TEN patients with ocular surface complications revealed 2 interactions that exerted SJS/TEN susceptibility effects, which were locus pairs of TLR3–PTGER3 and HLA-A–IL1&agr;. Furthermore, functional interactions between TLR3 and EP3 (the protein of PTGER3) were demonstrated using the EAC model. Identification of functional interactions between TLR3 and EP3 supports an epistatic interaction conferring an increased risk for SJS with ocular complications.
Oxidative‐inflammatory damage in cirrhosis: Effect of vitamin E and a fermented papaya preparation

Background and Aim: Oxidative DNA damage occurs as an early event in hepatitis C virus (HCV) infection and is an indication of the potential for carcinogenesis. The aim of this study was to test a novel antioxidant/immunomodulator in patients with HCV‐related cirrhosis.
Proteasome Subunits X and Y Alter Peptidase Activities in Opposite Ways to the Interferon-γ-induced Subunits LMP2 and LMP7*

Most antigenic peptides presented on major histocompatibility complex class I molecules are generated by proteasomes. Interferon-γ, which stimulates antigen presentation, induces new proteasome β-subunits LMP2 and LMP7, which replace the homologous β-subunits Y (δ) and X (ε). As a result, the capacity of the proteasome to cleave model peptides increases after hydrophobic and basic residues and falls after acidic residues. To clarify the function of these subunits, we examined the effects of overexpressing subunits X (δ) and Y (ε). Transfection of the Y gene into HeLa cells stimulated the proteasomal cleavage after acidic residues without altering other peptidase activities. This effect was proportional to the amount of the Y subunits and opposite to the effect of its homolog, LMP2. Y appears to promote cleavages after acidic residues. Furthermore, in mutants lacking the LMP genes (in contrast to wild-type cells), interferon-γ treatment increased the proteasome content of Y subunits and enhanced postacidic cleavages. Transfection with cDNA for the X subunit reduced hydrolysis after hydrophobic and basic residues, an effect opposite to transfection of LMP2 and LMP7. Surprisingly, transfection of X increased the amounts not only of X, but also of Y, while decreasing LMP2 content. Thus, the loss of the Y subunit upon interferon-γ treatment or LMP2 transfection accounts for the suppression of postacidic cleavages, and the loss of X contributes to the increased hydrolysis after hydrophobic and basic residues. These adaptations should favor the production of the kinds of peptides that are presented on major histocompatibility complex class I molecules.
Topology Control for Throughput Optimization in Wireless Mesh Networks

In this paper, we consider the problem of topology control by joint power control and routing to maximize the network throughput in wireless mesh networks. First, we present two mathematical formulations of the joint power control and routing problem according to two different definitions of network throughput: the total throughput and the minimal per-node throughput. To reduce the computation cost, we next decompose this joint problem into two sub-problems: the power control sub-problem and the routing sub-problem. For the first sub-problem, we design two heuristic algorithms to assign transmission powers to mesh routers, such that the total interference or the maximum node interference in the network is minimized. For the routing sub-problem, we design two linear programming formulations to maximize the total throughput or the minimal per-node throughput. Simulation results reveal the following relationship: the topology with minimum total interference has higher total throughput, while the topology with minimum maximal node interference has higher minimal per-node throughput. This can server as a guidance for network design to satisfy different throughput considerations.
Write-activity-aware page table management for PCM-based embedded systems

Due to its low power consumption and high density, phase change memory (PCM) becomes a promising main-memory alternative to DRAM in embedded systems. PCM, however, has the endurance problem in which the number of rewrites to each cell is quite limited compared with DRAM. Therefore, it is fundamental to eliminate unnecessary writes in PCM-based embedded systems. This paper presents a simple yet effective scheme to solve this problem, through redesigning existing software to exploit write-activity-aware features provided by underlying hardware. Particularly, we target at page table management, a key kernel component residing in the memory management part of the Linux kernel. We present for the first time a write-activity-aware page table management scheme, WAPTM, accomplished through two modifications to the page table initialization and page frame allocation process. The scheme has been implemented in Google Android 2.3 based on ARM architecture and evaluated with real applications on the Android emulator. The experimental results show that the proposed scheme can significantly reduce write activities to page tables in the new kernel compared with the original Android. We hope this work can serve as a first step towards the design of write-activity-aware operating systems via simple and feasible modifications.
β1 integrin- and JNK-dependent tumor growth upon hypofractionated radiation

Radiation therapy is an effective cancer treatment modality although tumors invariably become resistant. Using the transgenic adenocarcinoma of mouse prostate (TRAMP) model system, we report that a hypofractionated radiation schedule (10 Gy/day for 5 consecutive days) effectively blocks prostate tumor growth in wild type (β1wt /TRAMP) mice as well as in mice carrying a conditional ablation of β1 integrins in the prostatic epithelium (β1pc-/- /TRAMP). Since JNK is known to be suppressed by β1 integrins and mediates radiation-induced apoptosis, we tested the effect of SP600125, an inhibitor of c-Jun amino-terminal kinase (JNK) in the TRAMP model system. Our results show that SP600125 negates the effect of radiation on tumor growth in β1pc-/- /TRAMP mice and leads to invasive adenocarcinoma. These effects are associated with increased focal adhesion kinase (FAK) expression and phosphorylation in prostate tumors in β1pc-/- /TRAMP mice. In marked contrast, radiation-induced tumor growth suppression, FAK expression and phosphorylation are not altered by SP600125 treatment of β1wt /TRAMP mice. Furthermore, we have reported earlier that abrogation of insulin-like growth factor receptor (IGF-IR) in prostate cancer cells enhances the sensitivity to radiation. Here we further explore the β1/IGF-IR crosstalk and report that β1 integrins promote cell proliferation partly by enhancing the expression of IGF-IR. In conclusion, we demonstrate that β1 integrin-mediated inhibition of JNK signaling modulates tumor growth rate upon hypofractionated radiation.
Evaluation of pulmonary infiltrates in patients after stem cell transplantation

Abstract Hematopoietic stem cell transplantation is potentially curative therapy that has become the standard of care for many hematologic malignancies. Pulmonary complications occur in about 50% of stem cell transplant recipients and no other organ dysfunction has a higher mortality. Unfortunately the diagnosis of these infiltrates is hampered by the poor yield from routine studies and this patient population is rarely able to tolerate more risky procedures that will obtain tissue for microscopy and culture. A bronchoalveolar lavage (BAL) is usually insufficient to make a diagnosis of invasive fungal, significant bacterial, or pathogenic viral infections in patients that will still benefit from a change in therapy. In this review we discuss the infectious etiologies of pulmonary infiltrates post hematopoietic stem cell transplant, the non-infectious causes of infiltrates such as diffuse alveolar hemorrhage, engraftment syndrome, and idiopathic pneumonia syndrome, and the yield of newer diagnostic procedures ranging from peripheral blood galactomannan to cytomegalovirus antigenemia, and report on new technologies that promise more accurate and timely diagnoses of these infiltrates.
Trigeminal neuralgia (part I): Revisiting the clinical phenotype

Aims We conducted a cross-sectional study to re-examine the clinical profile of patients with a clinical diagnosis of classical trigeminal neuralgia (CTN). Methods Inclusion criteria consisted of the International Headache Society’s published classification of CTN. For the specific purposes of the study, features such as autonomic signs, persistent background pain, attack durations of >2 minutes and reports of pain-related awakening were included. The demographic and clinical phenotype of each patient were carefully recorded for analysis. Results The study cohort consisted of 81 patients and based on reported attack duration these were divided into short (≤ 2 minutes, n = 61) and long (> 2 minutes, n = 20) groups for further analysis. The group with short attack duration neatly fit most of the criteria for CTN while the long attack group presents a more challenging diagnosis. There were no significant differences in pain severity, quality and location between the short and long attack groups. The frequency of persistent background pain was significantly higher in the long (70%) compared to the short attack group (29.5%, p = 0.001). There were significantly more reports of pain-related awakenings in the long (55%) than in the short attack groups (29.5%, p = 0.04). There were no significant differences in the frequency of autonomic signs between the short (21.3%) and long attack groups (40%, p = 0.1). In the short attack group, the presence of autonomic signs was significantly associated with longer disease duration, increased pain-related awakenings, and a reduced prognosis. Conclusion There are clear diagnostic criteria for CTN but often patients present with features, such as long pain attacks, that challenge such accepted criteria. In our cohort the clinical phenotype of trigeminal, neuralgiform pain with or without autonomic signs and background pain was observed across both short and long attack groups and the clinical implications of this are discussed.
Passive Regenerative and Dissipative Snubber Cells for Isolated SEPIC Converters: Analysis, Design, and Comparison

An isolated converter such as SEPIC has high voltage stress on the main switch due to transformer leakage inductance. To solve this issue, active or passive clamp action is necessary. The common passive solution based on an RCD snubber is simple but impractical when the value of the leakage inductance is significant. On the other hand, passive regenerative solutions generally compromise the isolation, making the search for a suitable snubber a challenge. In this paper, an effective passive regenerative snubber cell for isolated SEPIC converters operating in DCM or CCM is presented. It is intended to improve the converter efficiency by transferring the energy stored in the transformer leakage inductance to the output. The analysis is presented in detail for DCM and extended to CCM together with a practical design procedure. In order to compare with the RCD, the analysis and design of a conventional cell are presented as well. To validate the proposal and quantify its feasibility, experimental results are performed for both dissipative and regenerative snubbers on a 100 W, 100 V, input and 50 V output voltage converter operating first in DCM and later in CCM.
Natural selection influences AFLP intraspecific genetic variability and introgression patterns in Atlantic eels

Investigating patterns of genetic variation in hybridizing species provides an opportunity to understand the impact of natural selection on intraspecific genetic variability and interspecific gene exchange. The Atlantic eels Anguilla rostrata and A. anguilla each occupy a large heterogeneous habitat upon which natural selection could differentially shape genetic variation. They also produce viable hybrids only found in Iceland. However, the possible footprint of natural selection on patterns of genetic variation within species and introgressive hybridization in Icelandic eels has never been assessed. We revisited amplified fragment length polymorphism data collected previously using population genomics and admixture analyses to test if (i) genetic variation could be influenced by non‐neutral mechanisms at both the intra‐ and interspecific levels, and if (ii) selection could shape the spatio‐temporal distribution of Icelandic hybrids. We first found candidate loci for directional selection within both species. Spatial distributions of allelic frequencies displayed by some of these loci were possibly related with the geographical patterns of life‐history traits in A. rostrata, and could have been shaped by natural selection associated with an environmental gradient along European coasts in A. anguilla. Second, we identified outlier loci at the interspecific level. Non‐neutral introgression was strongly suggested for some of these loci. We detected a locus at which typical A. rostrata allele hardly crossed the species genetic barrier, whereas three other loci showed accelerated patterns of introgression into A. anguilla in Iceland. Moreover, the level of introgression at these three loci increased from the glass eel to the yellow eel stage, supporting the hypothesis that differential survival of admixed genotypes partly explains the spatio‐temporal pattern of hybrid abundance previously documented in Iceland.
Progressive Transverse Cracking In Composite Laminates

HE DEVELOPMENT OF a satisfactory theory for cross-ply laminates which have been damaged by transverse matrix cracking under monotonic loading has attracted a substantial number of investigators. The formulation of a shear lag model appears to have been first proposed in a series of papers by Bailey and his co-workers [1,2,3,4,5,6]. This work, in turn, relies on some studies of unidirectional composites by Aveston and Kelly [6]. Subsequent contributions to the theory have geen given by Wang [7], Highsmith and Reifsnider [8], Flaggs and Kural [9], Nuismer and Tan [10], Manders, Chou, Jones and Rock [11], Fukunaga, Chou, Peters and Schulte [12], Flaggs [13], Ohira [14] and Ogin, Smith and Beaumont [15,16]. Doubtless a diligent search of the literature would disclose other related work.
Incidence, Distribution, and Spread of Tetracycline Resistance Determinants and Integron-Associated Antibiotic Resistance Genes among Motile Aeromonads from a Fish Farming Environment

ABSTRACT A collection of 313 motile aeromonads isolated at Danish rainbow trout farms was analyzed to identify some of the genes involved in high levels of antimicrobial resistance found in a previous field trial (A. S. Schmidt, M. S. Bruun, I. Dalsgaard, K. Pedersen, and J. L. Larsen, Appl. Environ. Microbiol. 66:4908–4915, 2000), the predominant resistance phenotype (37%) being a combined oxytetracycline (OTC) and sulphadiazine/trimethoprim resistance. Combined sulphonamide/trimethoprim resistance (135 isolates) appeared closely related to the presence of a class 1 integron (141 strains). Among the isolates containing integrons, four different combinations of integrated resistance gene cassettes occurred, in all cases including a dihydrofolate reductase gene and a downstream aminoglycoside resistance insert (87 isolates) and occasionally an additional chloramphenicol resistance gene cassette (31 isolates). In addition, 23 isolates had “empty” integrons without inserted gene cassettes. As far as OTC resistance was concerned, only 66 (30%) out of 216 resistant aeromonads could be assigned to resistance determinant class A (19 isolates), D (n = 6), or E (n = 39); three isolates contained two tetracycline resistance determinants (AD, AE, and DE). Forty OTC-resistant isolates containing large plasmids were selected as donors in a conjugation assay, 27 of which also contained a class 1 integron. Out of 17 successful R-plasmid transfers to Escherichia coli recipients, the respective integrons were cotransferred along with the tetracycline resistance determinants in 15 matings. Transconjugants were predominantly tetApositive (10 of 17) and contained class 1 integrons with two or more inserted antibiotic resistance genes. While there appeared to be a positive correlation between conjugative R-plasmids andtetA among the OTC-resistant aeromonads, tetEand the unclassified OTC resistance genes as well as class 1 integrons were equally distributed among isolates with and without plasmids. These findings indicate the implication of other mechanisms of gene transfer besides plasmid transfer in the dissemination of antibiotic resistance among environmental motile aeromonads.
Human aflatoxin exposure in Kenya, 2007: a cross-sectional study

Aflatoxins contaminate approximately 25% of agricultural products worldwide. They can cause liver failure and liver cancer. Kenya has experienced multiple aflatoxicosis outbreaks in recent years, often resulting in fatalities. However, the full extent of aflatoxin exposure in Kenya has been unknown. Our objective was to quantify aflatoxin exposure across Kenya. We analysed aflatoxin levels in serum specimens from the 2007 Kenya AIDS Indicator Survey – a nationally representative, cross-sectional serosurvey. KAIS collected 15,853 blood specimens. Of the 3180 human immunodeficiency virus-negative specimens with ≥1 mL sera, we randomly selected 600 specimens stratified by province and sex. We analysed serum specimens for aflatoxin albumin adducts by using isotope dilution MS/MS to quantify aflatoxin B1-lysine, and normalised with serum albumin. Aflatoxin concentrations were then compared by demographic, socioeconomic and geographic characteristics. We detected serum aflatoxin B1-lysine in 78% of serum specimens (range = <LOD–211 pg/mg albumin, median = 1.78 pg/mg albumin). Aflatoxin exposure did not vary by sex, age group, marital status, religion or socioeconomic characteristics. Aflatoxin exposure varied by province (p < 0.05); it was highest in Eastern (median = 7.87 pg/mg albumin) and Coast (median = 3.70 pg/mg albumin) provinces and lowest in Nyanza (median = <LOD) and Rift Valley (median = 0.70 pg/mg albumin) provinces. Our findings suggest that aflatoxin exposure is a public health problem throughout Kenya, and it could be substantially impacting human health. Wide-scale, evidence-based interventions are urgently needed to decrease exposure and subsequent health effects.
Department of Mathematics

At the MS level, a student can be enrolled either in the campus program or in the distance (online program). For the distance MS program, two tracks are available: computational math and math teaching. For the campus MS program, five tracks are available: traditional (generally, preparation to continue with a PhD), math teaching, computational math, industrial math, and math biology. Students in the campus MS program can pursue either a thesis or a non-thesis degree.