Miracle-dz/UniFAR-FTUs huggingface dataset:
Helical distribution of the bacterial chemoreceptor via colocalization with the Sec protein translocation machinery

In Escherichia coli, chemoreceptor clustering at a cell pole seems critical for signal amplification and adaptation. However, little is known about the mechanism of localization itself. Here we examined whether the aspartate chemoreceptor (Tar) is inserted directly into the polar membrane by using its fusion to green fluorescent protein (GFP). After induction of Tar–GFP, fluorescent spots first appeared in lateral membrane regions, and later cell poles became predominantly fluorescent. Unexpectedly, Tar–GFP showed a helical arrangement in lateral regions, which was more apparent when a Tar–GFP derivative with two cysteine residues in the periplasmic domain was cross‐linked to form higher oligomers. Moreover, similar distribution was observed even when the cytoplasmic domain of the double cysteine Tar–GFP mutant was replaced by that of the kinase EnvZ, which does not localize to a pole. Observation of GFP–SecE and a translocation‐defective MalE–GFP mutant, as well as indirect immunofluorescence microscopy on SecG, suggested that the general protein translocation machinery (Sec) itself is arranged into a helical array, with which Tar is transiently associated. The Sec coil appeared distinct from the MreB coil, an actin‐like cytoskeleton. These findings will shed new light on the mechanisms underlying spatial organization of membrane proteins in E. coli.
Eukaryotic expression: developments for structural proteomics

The production of sufficient quantities of protein is an essential prelude to a structure determination, but for many viral and human proteins this cannot be achieved using prokaryotic expression systems. Groups in the Structural Proteomics In Europe (SPINE) consortium have developed and implemented high‐throughput (HTP) methodologies for cloning, expression screening and protein production in eukaryotic systems. Studies focused on three systems: yeast (Pichia pastoris and Saccharomyces cerevisiae), baculovirus‐infected insect cells and transient expression in mammalian cells. Suitable vectors for HTP cloning are described and results from their use in expression screening and protein‐production pipelines are reported. Strategies for co‐expression, selenomethionine labelling (in all three eukaryotic systems) and control of glycosylation (for secreted proteins in mammalian cells) are assessed.
Modeling and Analyzing Server System with Rejuvenation through SysML and Stochastic Reward Nets

High-availability assurance of server systems is becoming an important issue, since many mission-critical applications are implemented on server systems. To achieve high-availability, software rejuvenation is a practical technique to reduce unexpected downtime caused by software aging in software applications running on server systems. Although analytic models of software rejuvenation are well-studied, such analysis is not used in server system administration due to the complexity of modeling. In this paper, we present an availability modeling method for server system with software rejuvenation based on SysML that is used to describe system configurations and maintenance operations semi-formally. The proposed approach allows system administrators, who do not have expertise in availability modeling, to design and study the effects of different rejuvenation policies deployed in server systems. To show the applicability of the proposed modeling and evaluation process, a case study of a web application server is presented. We show the correctness of our modeling method by comparing the conventional models for condition-based and time-based software rejuvenation.
On the Tensile Properties of Polylactide (PLA)/Arenga Pinnata “Ijuk” Fibre Composite

Summary Composite as a plastic material derivative was widely used in various facets of life. Problems arising from the use of these common materials, among others, lies in the processing of components' waste that has reached the end of its life span. Through the use of polymeric materials derived from natural materials, namely poly lactic acid / polylactide (PLA), as well as reinforcing material prepared from natural fibers such as Arenga pinnata / ijuk fibers, polymer composites was made by hot compression molding (hot pressing). Chemical treatments with sodium hydroxide (NaOH) with a set treatment time and concentration were conducted on short fibres to improve compatibility with the matrix. Moreover, the effect of variation of volume fraction will be observed in the form of reinforcement levels (10, 20, and 30% of the total weight of starting material) on the properties (tensile strength, modulus of elasticity, elongation) of the resulting composites. The properties in question are tensile properties, and fibre – matrix compatibility. It was expected that the treatment would bring positive effect to the mechanical properties of composite and compatibility of fibre and matrix compared to the ones without treatment.
Throughput of CDMA Data Networks With Reduced-Rank MMSE Receivers and Automatic Retransmission Request

Reduced-rank MMSE receivers have been proposed for CDMA communication systems recently. The output SINR, provided by a reduced-rank receiver depends on the filter rank and is confined between the SINRs of the single user matched filter (SUMF) and the minimum mean squared error (MMSE) receiver. The same remark is valid for the bit error rate (BER). In packet CDMA data networks like HSDPA, the measure of performance is the throughput. Thus, previous results on reduced-rank MMSE receivers SINR cannot be used directly. In this paper, we study the throughput of CDMA data networks using reduced-rank MMSE receivers, automatic retransmission request (ARQ) and packet combining. We study the effect of the filter rank on the throughput of the system.
High-speed bounding with the MIT Cheetah 2: Control design and experiments

This paper presents the design and implementation of a bounding controller for the MIT Cheetah 2 and its experimental results. The paper introduces the architecture of the controller along with the functional roles of its subcomponents. The application of impulse scaling provides feedforward force profiles that automatically adapt across a wide range of speeds. A discrete gait pattern stabilizer maintains the footfall sequence and timing. Continuous feedback is layered to manage balance during the stance phase. Stable hybrid limit cycles are exhibited in simulation using simplified models, and are further validated in untethered three-dimensional bounding experiments. Experiments are conducted both indoors and outdoors on various man-made and natural terrains. The control framework is shown to provide stable bounding in the hardware, at speeds of up to 6.4 m/s and with a minimum total cost of transport of 0.47. These results are unprecedented accomplishments in terms of efficiency and speed in untethered experimental quadruped machines.
Prevalence and antibiogram of Extended Spectrum β-Lactamase (ESBL) producing Gram negative bacilli and further molecular characterization of ESBL producing Escherichia coli and Klebsiella spp.

BACKGROUND AND OBJECTIVES Resistance to a wide variety of common antimicrobials has made the proliferation of Extended spectrum β-lactmase (ESBL) producing strains a serious global health concern that has complicated treatment strategies. The high proportion of ESBL producers among the Enterobacteriaceae and the complex molecular epidemiology with diverse types of ESBL genes are alarming. This study was undertaken to identify ESBL production in various Gram negative bacilli isolated and to further characterize ESBL producers among Escherichia coli and Klebsiella spp by PCR, which were initially screened by phenotypic method. MATERIALS AND METHODS A total of 722 isolates of Gram negative bacilli were isolated. Presence of ESBL positivity was detected using the double disk synergy test (DDST). Their antibiogram was studied. PCR analysis for β-lactamase (bla) genes of the family TEM, SHV and CTX-M was also carried out using designed primers in 20 ESBL isolates each of Escherichia coli and Klebsiella spp. RESULTS Among 722 Gram negative bacilli isolated 379 (52.49%) were ESBL producers. The major source of ESBL producers were respiratory tract samples, highest ESBL production was observed in Klebsiella sp. (67.04%). Resistance to multiple classes of antibiotics was observed among ESBL producers. Among ESBL producing genes prevalence of bla-CTX-M (82.5%) was highest, followed by bla-TEM (67.5%) and bla-SHV (57.5%) in the present study. The frequency of ESBL producing strains among clinical isolates has been steadily increasing. Advance drug resistance surveillance and molecular characteristics of ESBL isolates is necessary to guide the appropriate and judicious antibiotic use.
How good are the visual MPEG-7 features?

The study presented in this paper analyses descriptions extracted with MPEG-7-descriptors from visual content from the statistical point of view. Good descriptors should generate descriptions with high variance, a well-balanced cluster structure and high discriminance to be able to distinguish different media content. Statistical analysis reveals the quality of the used description extraction algorithms. This was not considered in the MPEG-7-design process where optimising the recall was the major goal. For the analysis eight basic visual descriptors were applied on three media collections: the Brodatz dataset (monochrome textures), a selection of the Corel dataset (colour photos) and a set of coats-of-arms images (artificial colour images with few colour gradations). The results were analysed with four statistical methods: mean and variance of descriptor elements, distribution of elements, cluster analysis (hierarchical and topological) and factor analysis. The main results are: The best descriptors for combination are Color Layout, Dominant Color, Edge Histogram and Texture Browsing. The other are highly dependent on these. The colour histograms (Color Structure and Scalable Color) perform badly on monochrome input. Generally, all descriptors are highly redundant and the application of complexity reduction transformations could save up to 80% of storage and transmission capacity.
Proteasome inhibition modulates kinase activation in neural cells: Relevence to ubiquitination, ribosomes, and survival

In this study we examined whether established signal transduction cascades, p44/42 mitogen‐activated protein kinase (ERK1/2) and Jun N‐terminal kinases (JNK) pathways, are altered in N2a neural cells in response to proteasome inhibition. Additionally, we sought to elucidate the relative contribution of these signal transduction pathways to the multiple downstream effects of proteasome inhibition. Our data indicate that ERK1/2 and JNK are activated in response to proteasome inhibition. Washout of proteasome inhibitor (MG132) results in an enhancement of ERK1/2 activation and amelioration of JNK activation. Treatment with an established MAPK inhibitor resulted in an increase in proteasome inhibitor toxicity, and incubation with JNK inhibitor was observed to attenuate proteasome inhibitor toxicity significantly. Subsequent studies demonstrated that inhibition of ERK1/2 and JNK activity does not alter the gross increase in ubiquitinated protein following proteasome inhibitor administration. Similarly, ERK1/2 and JNK activity do not appear to play a role in the disruption of polysomes following proteasome inhibitor administration in neural cells. Together these data indicate that ERK1/2 and JNK activation may play differential roles in modulating neurochemical disturbances and neurotoxicity induced by proteasome inhibition. © 2009 Wiley‐Liss, Inc.
Fatigue Crack Growth Rate Characteristics of Laser Shock Peened Ti-6Al-4V

The fatigue crack growth rate (FCGR) characteristics of Laser Shock Peened (LSP) titanium 6Al-4V were examined and compared to those of unprocessed material. The FCGR resistance of LSP processed material tested at low stress ratios (R) is shown to be significantly greater than for unprocessed, baseline material. The increased damage tolerance can be attributed to the large residual compressive stresses generated by the LSP process. Differences in the growth rate behavior due to LSP can be accounted for by using the closure corrected effective stress intensity range. {Delta}K{sub eff}, which takes into account only the portion of loading above the crack opening load. The rationale of using {Delta}K{sub eff} is also demonstrated through fractographic investigations.
Phosphodiesterase 4 Inhibitors Augment Levels of Glucocorticoid Receptor in B Cell Chronic Lymphocytic Leukemia but Not in Normal Circulating Hematopoietic Cells

Type 4 cyclic AMP (cAMP) phosphodiesterase (PDE4) inhibitors, a class of compounds in clinical development that activate cAMP-mediated signaling by inhibiting cAMP catabolism, offer a feasible means by which to potentiate glucocorticoid-mediated apoptosis in lymphoid malignancies such as B-cell chronic lymphocytic leukemia (B-CLL). In this study, we show that PDE4 inhibitors up-regulate glucocorticoid receptor (GRα) transcript levels in B-CLL cells but not T-CLL cells or Sezary cells or normal circulating T cells, B cells, monocytes, or neutrophils. Because GRα transcript half-life does not vary in CLL cells treated with the prototypic PDE4 inhibitor rolipram, the 4-fold increase in GRα mRNA levels observed within 4 h of rolipram treatment seems to result from an increase in GRα transcription. Rolipram treatment increases levels of transcripts derived from the 1A3 promoter to a greater extent than the 1B promoter. Treatment of B-CLL cells with two other PDE4 inhibitors currently in clinical development also augments GR transcript levels and glucocorticoid-mediated apoptosis. Washout studies show that simultaneous treatment with both drug classes irreversibly augments apoptosis over the same time frame that GR up-regulation occurs. Although treatment of B-CLL cells with glucocorticoids reduces basal GRα transcript levels in a dose-related manner, cotreatment with rolipram maintained GRα transcript levels above baseline. Our results suggest that as a result of their unusual sensitivity to PDE4 inhibitor–mediated up-regulation of GRα expression, treatment of B-CLL patients with combined PDE4 inhibitor/glucocorticoid therapy may be of therapeutic benefit in this disease.
Properties of D mesons in nuclear matter within a self-consistent coupled-channel approach

The spectral density of the $D$ meson in the nuclear environment is studied within a self-consistent coupled-channel approach assuming a separable potential for the bare meson-baryon interaction. The $DN$ interaction, described through a $G$ matrix, generates dynamically the ${\ensuremath{\Lambda}}_{c}(2593)$ resonance. This resonance is the charm counterpart of the $\ensuremath{\Lambda}(1405)$ resonance generated from the $s$-wave $\overline{K}N$ interaction in the $I=0$ channel. The medium modification of the $D$-meson spectral density due to the Pauli blocking of intermediate states as well as due to the dressing of the $D$ mesons, nucleons, and pions is investigated. We observe that the inclusion of coupled-channel effects and the self-consistent dressing of the $D$ meson results in an overall reduction of the in-medium $D$-meson changes compared to previous work which neglected those effects.
Call Admission Control in Mobile Cellular Networks : A Comprehensive Survey

Call admission control is a key element in the provision of guaranteed quality of service in wireless networks. The design of call admission control algorithms for mobile cellular networks is especially challenging given the limited and highly variable resources, and the mobility of users encountered in such networks. This article provides a survey of admission control schemes for cellular networks and the research in this area. Our goal is to provide a broad classification and thorough discussion of existing call admission control schemes. We classify these schemes based on factors such as deterministic/stochastic guarantees, distributed/local control and adaptivity to traffic conditions. In addition to this, we present some modeling and analysis basics to help in better understanding the performance and efficiency of admission control schemes in cellular networks. We describe several admission control schemes and compare them in terms of performance and complexity. Handoff prioritization is the common characteristic of these schemes. We survey different approaches proposed for achieving handoff prioritization with a focus on reservation schemes. Moreover, optimal and near-optimal reservation schemes are presented and discussed. Also, we overview other important schemes such as those designed for multi-service networks and hierarchical systems as well as complete knowledge schemes and those using pricing for call admission control. Finally, the paper concludes on the state of current research and points out some of the key issues that need to be addressed in the context of call admission control for future cellular networks.
Effectiveness of photosensitive dye during uptake and redistribution

The location of photosensitive dye within a cell will affect the efficacy of photodynamic therapy (PDT). This report demonstrates that during the first 3 hours of dye (Photofrin porfimer) uptake from a liquid medium, the dye is diffusely distributed within the cell. After 24 hours of dye uptake, the dye is localized in specific sites within the cell. Fluorescence spectroscopy demonstrated that the 3-hour dye's emission peak near 635 nm was slightly blue shifted for the localized 24-hour dye. This paper demonstrates that the diffuse dye (at 3 hours) is more effective for PDT than the localized dye (at 24 hours). The amount of diffuse dye within the cell that is required to achieve an LD50 (50% lethal dose) is 1.5-fold to 4.5- fold less than the amount of localized dye required, using the same light exposure. The range of 1.5 - 4.5-fold refers to the results for four cell lines.
Effects of Different Resuscitation Fluids on Pulmonary Expression of Aquaporin1 and Aquaporin5 in a Rat Model of Uncontrolled Hemorrhagic Shock and Infection

Background To investigate the effects of fluids resuscitation on pulmonary expression of aquaporin1 and aquaporin5 in a rat model of uncontrolled hemorrhagic shock and infection. Methods Sixty Sprague-Dawley rats were randomly assigned to five groups, sham operation group (Group C) and four treated groups: no fluid resuscitation group (Group NF), groups resuscitated with Lactated Ringer's (LR),7.5% NaCl (HTS) and Hydroxyl ethyl starch (HES) respectively. Three-phased uncontrolled hemorrhagic shock and infection model was used. Phase I: Massive hemorrhage with a mean arterial pressure of 35–40 mmHg for 60 min, and followed by infection of lipopolysaccharide. Then some animals were resuscitated with solutions mentioned above, until 90 min. Phase II: At hemorrhagic shock 90 minutes, phase II of 60 minutes began with hemostasis and returning of all the initial shed blood. Phase III: Observation phase for 3.5 hours. After phase III, arterial blood gas analysis and the survival rates of the rats were recorded, Wet-to-dry lung weight ratio, BALF protein, pulmonary permeability index, and expressions of aquaporin1 and aquaporin5 were tested. Results The expressions of aquaporin1 and aquaporin5 were decreased in treatment groups comparing with sham operation group. Group HES and Group HTS decreased pulmonary vascular permeability and Wet-to-dry lung weight ratio, improved arterial blood gas analysis and survival rates, and attenuated the decreased pulmonary expression of aquaporin1 and aquaporin5 after the “two-hit”, comparing with groups NF and LR,but these beneficial effects were blunted in group HTS. Conclusion The expression of aquaporin1 and aquaporin5 may play important roles in formation of pulmonary edema. Resuscitation with HTS and HES, especially HES can reduce lung injury after hemorrhagic shock, partly by up-regulating the expressions of aquaporin1 and aquaporin5.
Performance Analysis of Dual-Hop Amplify-and-Forward Systems with Multiple Antennas and Co-channel Interference

This paper investigates the performance of a dual-hop amplify-and-forward relaying system with co-channel interference at both the relay and destination nodes. The source node is equipped with multiple antennas and adopts the orthogonal space-time block code to increase the system performance. Both the outage probability and the average bit error rate under the presence of multiple Rayleigh fading interferers are obtained in closed form for the variable and fixed-gain relaying schemes. Moreover, the effect of imperfect channel estimation on the variable-gain relaying scheme is also discussed. The effect of co-channel interference at both the relay and destination nodes are discussed. Simulation experiments are also conducted to verify the theoretical derivations.
Problems Faced by Novice Principals in Malaysia: An Exploration Study

This study explores the problems faced by novice principals and their impact on work performance. Based on a qualitative research design, we adopted an exploratory design and applied in-depth interview method through purposive sampling for which eight novice principals were interviewed. The findings indicate that novice principals faced various problems such as isolation, time management difficulty, lack of position-related knowledge, failure to integrate theories with real practices, lack of experience in decision-making and problem solving, and inability to adapt to the culture at the new school. Such situations assert undue pressure on the novice principals to the extent of affecting their performance in the initial stage of their appointment as school administrators. These findings suggest that novice principals should attend the National Professional Qualification for Educational Leader course for exposure to theories of school leadership and management. In addition, the findings further suggest implementing socialisation and induction programs for novice principals prior to their appointment.
An ambusher's arsenal: chemical crypsis in the puff adder (Bitis arietans)

Ambush foragers use a hunting strategy that places them at risk of predation by both visual and olfaction-oriented predators. Resulting selective pressures have driven the evolution of impressive visual crypsis in many ambushing species, and may have led to the development of chemical crypsis. However, unlike for visual crypsis, few studies have attempted to demonstrate chemical crypsis. Field observations of puff adders (Bitis arietans) going undetected by several scent-orientated predator and prey species led us to investigate chemical crypsis in this ambushing species. We trained dogs (Canis familiaris) and meerkats (Suricata suricatta) to test whether a canid and a herpestid predator could detect B. arietans using olfaction. We also tested for chemical crypsis in five species of active foraging snakes, predicted to be easily detectable. Dogs and meerkats unambiguously indicated active foraging species, but failed to correctly indicate puff adder, confirming that B. arietans employs chemical crypsis. This is the first demonstration of chemical crypsis anti-predatory behaviour, though the phenomenon may be widespread among ambushers, especially those that experience high mortality rates owing to predation. Our study provides additional evidence for the existence of an ongoing chemically mediated arms race between predator and prey species.