Miracle-dz/UniFAR-FTUs huggingface dataset:
Understanding I/O performance behaviors of cloud storage from a client's perspective

Cloud storage has gained increasing popularity in the past few years. In cloud storage, data is stored in the service provider's data centers, and users access data via the network. For such a new storage model, our prior wisdom about conventional storage may not remain valid nor applicable to the emerging cloud storage. In this paper, we present a comprehensive study and attempt to gain insight into the unique characteristics of cloud storage, primarily from the client's perspective. Through extensive experiments and quantitative analysis, we have acquired several interesting, and in some cases unexpected, findings. (1) Parallelizing I/Os and increasing request sizes are keys to improving the performance, but optimal bandwidth may only be achieved with a proper combination of parallelism and request size. (2) Client capabilities, including CPU, memory, and storage, play an unexpectedly important role in determining the achievable performance. (3) A geographically long distance affects client-perceived performance but does not always result in lower bandwidth and longer latency. Based on our experimental studies, we further present a case study on appropriate chunking and parallelization in a cloud storage client. Our studies show that specific attention should be paid to fully exploiting the capabilities of clients and the great potential of cloud storage services.
Joint Communication, Computation, Caching, and Control in Big Data Multi-Access Edge Computing

The concept of Multi-access Edge Computing (MEC) has been recently introduced to supplement cloud computing by deploying MEC servers to the network edge so as to reduce the network delay and alleviate the load on cloud data centers. However, compared to the resourceful cloud, MEC server has limited resources. When each MEC server operates independently, it cannot handle all computational and big data demands stemming from users devices. Consequently, the MEC server cannot provide significant gains in overhead reduction of data exchange between users devices and remote cloud. Therefore, joint Computing, Caching, Communication, and Control (4C) at the edge with MEC server collaboration is needed. To address these challenges, in this paper, the problem of joint 4C in big data MEC is formulated as an optimization problem whose goal is to jointly optimize a linear combination of the bandwidth consumption and network latency. However, the formulated problem is shown to be non-convex. As a result, a proximal upper bound problem of the original formulated problem is proposed. To solve the proximal upper bound problem, the block successive upper bound minimization method is applied. Simulation results show that the proposed approach satisfies computation deadlines and minimizes bandwidth consumption and network latency.
The Primary Resistance of Helicobacter pylori in Taiwan after the National Policy to Restrict Antibiotic Consumption and Its Relation to Virulence Factors—A Nationwide Study

Objective The Taiwan Government issued a policy to restrict antimicrobial usage since 2001. We aimed to assess the changes in the antibiotic consumption and the primary resistance of H. pylori after this policy and the impact of virulence factors on resistance. Methods The defined daily dose (DDD) of antibiotics was analyzed using the Taiwan National Health Insurance (NHI) research database. H. pylori strains isolated from treatment naïve (N=1395) and failure from prior eradication therapies (N=360) from 9 hospitals between 2000 and 2012 were used for analysis. The minimum inhibitory concentration was determined by agar dilution test. Genotyping for CagA and VacA was determined by PCR method. Results The DDD per 1000 persons per day of macrolides reduced from 1.12 in 1997 to 0.19 in 2008, whereas that of fluoroquinolones increased from 0.12 in 1997 to 0.35 in 2008. The primary resistance of amoxicillin, clarithromycin, metronidazole, and tetracycline remained as low as 2.2%, 7.9%, 23.7%, and 1.9% respectively. However, the primary levofloxacin resistance rose from 4.9% in 2000–2007 to 8.3% in 2008–2010 and 13.4% in 2011–2012 (p=0.001). The primary resistance of metronidazole was higher in females than males (33.1% vs. 18.8%, p<0.001), which was probably attributed to the higher consumption of nitroimidazole. Neither CagA nor VacA was associated with antibiotic resistance. Conclusions The low primary clarithromycin and metronidazole resistance of H. pylori in Taiwan might be attributed to the reduced consumption of macrolides and nitroimidazole after the national policy to restrict antimicrobial usage. Yet, further strategies are needed to restrict the consumption of fluoroquinolones in the face of rising levofloxacin resistance.
Effect of woven flax structures on morphology and properties of reinforced modified polylactide composites

Composites composed of polylactide (PLA), modified PLA and woven flax fiber textiles (flax weave style of 2 × 2 twill and 4 × 4 hopsack) were produced by hot press technique. Two structurally different additives were used to modify PLA. The dispersion of the flax in the composites was studied by scanning electron microscopy and computed microtomography system (µCT). The PLA composites were subjected to water absorption and instrumented falling weight impact tests. The thermomechanical and creep properties of the composites were determined using thermogravimetric analysis, dynamic-mechanical thermal analysis and short-time creep tests. It was found that the modified PLA and its composite increased the impact resistance compared with the unmodified PLA. Incorporation of flax decreased resistance to thermal degradation and increased water uptake. The impact energy and stiffness value of PLA/flax composites were markedly higher than that of PLA but reflect the effects of composite structures and flax content. The storage modulus master curves were constructed by applying the time–temperature superposition principle. From the master curve data, the effect of modified PLA on the storage modulus was more pronounced in the low frequency range.
Resistencia de los refractarios al choque térmico. I: Aproximación termoelástica y criterio de balance energético

espanolSe describe el comportamiento de los materiales refractarios sometidos a tensiones termicas. Se revisan las dos aproximaciones clasicas al estudio de la resistencia de los materiales fragiles al choque termico. Se analiza el margen de validez de estas aproximaciones en base a trabajos experimentales realizados sobre materiales refractarios. EnglishThe behaviour of refractory materials subjected to thermal stresses is described. The two classical approaches used to study the thermal shock resistance of brittle materials are reviewed. The validity of these approaches is analyzed using published experimental work on refractories.
Lead phytoextraction from printed circuit computer boards by Lolium perenne L. and Medicago sativa L.

ABSTRACT This work assessed the ability of Lolium perenne and Medicago sativa for extracting lead (Pb) from particulate printed circuit computer boards (PCB) mixed in sand with the following concentrations: 0.5, 1.0 and 1.5 g of PCB, and including a control treatment without PCB. The PCB were obtained from computers, and grinded in two particle sizes: 0.0594 mm (PCB1) and 0.0706 mm (PCB2). The PCB particle sizes at their corresponding concentrations were applied to L. perenne and M. sativa by using three experimental assays. In assay II, PCB2 affected the biomass production for both plants. For assay III, the PCB1 increased the biomass of M. sativa (236.5%) and L. perenne (142.2%) when applying either 0.5 or 1.0 g, respectively. In regards to phytoextraction, assay I showed the highest Pb-extraction by roots of L. perenne (4.7%) when exposed to 1.5 g of PCB1. At assay I, L. perenne showed a Pb-bioconcentration factor higher than 1.0 when growing at 0.5 g of PCB1, and when HNO3 was used as digestion solution; moreover, in assay III both plants showed a Pb-translocation factor higher than 1.0. Therefore, Lolium perenne and Medicago sativa are able to recover Pb from electronic wastes (PCB).
Deconstruction of the Ras switching cycle through saturation mutagenesis

Ras proteins are highly conserved signaling molecules that exhibit regulated, nucleotide-dependent switching between active and inactive states. The high conservation of Ras requires mechanistic explanation, especially given the general mutational tolerance of proteins. Here, we use deep mutational scanning, biochemical analysis and molecular simulations to understand constraints on Ras sequence. Ras exhibits global sensitivity to mutation when regulated by a GTPase activating protein and a nucleotide exchange factor. Removing the regulators shifts the distribution of mutational effects to be largely neutral, and reveals hotspots of activating mutations in residues that restrain Ras dynamics and promote the inactive state. Evolutionary analysis, combined with structural and mutational data, argue that Ras has co-evolved with its regulators in the vertebrate lineage. Overall, our results show that sequence conservation in Ras depends strongly on the biochemical network in which it operates, providing a framework for understanding the origin of global selection pressures on proteins. DOI: http://dx.doi. org/10.7554/eLife.27810. 001
Processing and damage recovery of intrinsic self-healing glass fiber reinforced composites

Glass fiber reinforced composites with a self-healing, supramolecular hybrid network matrix were produced using a modified vacuum assisted resin infusion moulding process adapted to high temperature processing. The quality and fiber volume fraction (50%) of the obtained materials were assessed through microscopy and matrix burn-off methods. The thermo-mechanical properties were quantified by means of dynamic mechanical analysis, revealing very high damping properties compared to traditional epoxy-based glass fiber reinforced composites. Self-healing properties were assessed by three-point bending tests. A high recovery of the flexural properties, around 72% for the elastic modulus and 65% of the maximum flexural stress, was achieved after a resting period of 24 h at room temperature. Recovery after low velocity impact events was also visually observed. Applications for this intrinsic and autonomic self-healing highly reinforced composite material point towards semi-structural applications where high damping and/or integrity recovery after impact are required.
Metabolomics reveals critical adrenergic regulatory checkpoints in glycolysis and pentose–phosphate pathways in embryonic heart

Cardiac energy demands during early embryonic periods are sufficiently met through glycolysis, but as development proceeds, the oxidative phosphorylation in mitochondria becomes increasingly vital. Adrenergic hormones are known to stimulate metabolism in adult mammals and are essential for embryonic development, but relatively little is known about their effects on metabolism in the embryonic heart. Here, we show that embryos lacking adrenergic stimulation have ∼10-fold less cardiac ATP compared with littermate controls. Despite this deficit in steady-state ATP, neither the rates of ATP formation nor degradation was affected in adrenergic hormone-deficient hearts, suggesting that ATP synthesis and hydrolysis mechanisms were fully operational. We thus hypothesized that adrenergic hormones stimulate metabolism of glucose to provide chemical substrates for oxidation in mitochondria. To test this hypothesis, we employed a metabolomics-based approach using LC/MS. Our results showed glucose 1-phosphate and glucose 6-phosphate concentrations were not significantly altered, but several downstream metabolites in both glycolytic and pentose–phosphate pathways were significantly lower compared with controls. Furthermore, we identified glyceraldehyde-3-phosphate dehydrogenase and glucose-6-phosphate dehydrogenase as key enzymes in those respective metabolic pathways whose activity was significantly (p < 0.05) and substantially (80 and 40%, respectively) lower in adrenergic hormone-deficient hearts. Addition of pyruvate and to a lesser extent ribose led to significant recovery of steady-state ATP concentrations. These results demonstrate that without adrenergic stimulation, glucose metabolism in the embryonic heart is severely impaired in multiple pathways, ultimately leading to insufficient metabolic substrate availability for successful transition to aerobic respiration needed for survival.
Top‐down estimate of China's black carbon emissions using surface observations: Sensitivity to observation representativeness and transport model error

This study examines the sensitivity of “top‐down” quantification of Chinese black carbon (BC) emissions to the temporal resolution of surface observations and to the transport model error associated with the grid resolution and wet deposition. At two rural sites (Miyun in North China Plain and Chongming in Yangtze River Delta), the model‐inferred emission bias based on hourly BC observations can differ by up to 41% from that based on monthly mean observations. This difference relates to the intrinsic inability of the grid‐based model in simulating high pollution plumes, which often exert a larger influence on the arithmetic mean of observations at monthly time steps. Adopting the variation of BC to carbon monoxide correlation slope with precipitation as a suitable measure to evaluate the model's wet deposition, we found that wet removal of BC in the model was too weak, due in part to the model's underestimation of large precipitation events. After filtering out the observations during high pollution plumes and large precipitation events for which the transport model error should not be translated into the emission error, the inferred emission bias changed from −11% (without filtering) to −2% (with filtering) at the Miyun site, and from −22% to +1% at the Chongming site. Using surface BC observations from three more rural sites (located in Northeast, Central, and Central South China, respectively) as constraints, our top‐down estimate of total BC emissions over China was 1.80 ± 0.65 Tg/yr in 2006, 0.5% lower than the bottom‐up inventory of Zhang et al. (2009) but with smaller uncertainty.
Functional Capacity Evaluation Following Spinal Fusion Surgery

Study Design. Retrospective review of prospectively collected data. Objective. The aim of the study was to characterize outcomes of functional capacity evaluations (FCEs) amongst patients undergoing spinal fusion surgery. Summary of Background Data. Injured workers often undergo an FCE upon reaching maximal medical improvement following surgery. To date, few studies have examined the results of FCEs following spinal fusion. Methods. Patients undergoing an FCE following a minimally invasive transforaminal lumbar interbody fusion (TLIF) or anterior cervical discectomy and fusion (ACDF) were retrospectively identified. Based upon the FCE report, each patient's job-related preoperative physical requirement and postoperative work capability was categorized as light, medium, or heavy. Patients were characterized as being able to meet their preoperative job requirement if their FCE-determined capability was greater than or equal to their preoperative job requirement. Patient characteristics were tested for association with meeting preoperative job requirement using bivariate and multivariate regression. Results. A total of 173 patients were identified: 71 (41.0%) and 102 (59.0%) underwent TLIF and ACDF, respectively. Of the 71 TLIF and 102 ACDF patients, 41 (58%) and 50 (49%) had light postoperative capabilities, 18 (25%) and 38 (37%) as medium, and 12 (17%) and 14 (14%) as heavy, respectively. Postoperatively, 26 (37%) of TLIF and 55 (54%) of ACDF patients were categorized as meeting their preoperative job requirement. Independent predictors of meeting preoperative job requirement following TLIF (P =0.002) and ACDF (P = 0.037) were lower preoperative job requirement, and younger age for ACDF (P < 0.001). Conclusion. Only one in five patients undergoing spinal fusion surgery for occupational injuries is able to perform heavy-duty work postoperatively. Similarly, approximately half of patients are able to perform medium-duty work. Moreover, a majority of patients are unable to return to their preoperative occupational responsibilities. These findings can be used to council patients regarding their likelihood of meeting postoperative work capacity. Level of Evidence: 3
Use of Bendamustine in Chronic Lymphocytic Leukaemia Patients with Co-morbidities

Chronic lymphocytic leukaemia (CLL) is the most common adult leukaemia and mainly affects older patients. First-line treatments for 'fit' (go go) and 'unfit' (no go) CLL patients are well defined, in the form of fludarabine–cyclophosphamide–rituximab (FCR) combination chemoimmunotherapy and best supportive care, respectively. However, the majority of CLL patients fall between these two extremes (slow go patients), nevertheless the standard of care for these patients is not well defined. Recent data suggest that bendamustine chemotherapy may be a good option in this group. In a recent Phase III study, significant improvements in overall response rate, complete response and progression-free survival were reported with bendamustine compared with chlorambucil. Chlorambucil plus rituximab has been shown to induce high responses in elderly CLL patients with a relatively low complete response rate. Bendamustine plus rituximab, and reduced-dose fludarabine plus cyclophosphamide plus high-dose rituximab have demonstrated promising efficacy, but have not been evaluated in elderly CLL patients. Several trials are also ongoing evaluating novel cytostatic agents, combination chemotherapy and chemoimmunotherapy regimens in elderly patients.
Depressive vulnerability, stressful life events and episode onset of major depression: a longitudinal model

Background The nature of the relationship between depressive vulnerability (DV) and acute adversity in the etiology of major depression (MD) remains poorly understood. Method Stressful life events (SLEs) and MD onsets in the last year were assessed at four waves in cohort 1 (females) and at two waves in cohort 2 (males and females) from the Virginia Adult Twin Study. Structural equation modeling was conducted in Mplus. Results In cohort 1, DV was strongly indexed by depressive episodes over the four waves (paths from +0.72 to 0.79) and predicted by SLEs in the month of their occurrence (+0.31 to 0.36). Wave-specific DV was associated both with stable DV (+0.29 to 0.33) and by forward transmission of DV from the preceding wave (+0.33 to 0.36). SLEs were predicted by stable DV (+0.29) and from SLEs in the preceding month (+0.06). As the cohort aged, MD onsets were better indexed by DV and more poorly predicted by SLEs. Parameter estimates were similar in males and females from cohort 2. In individuals with prior depressive episodes, the association between MD onset and SLEs was weakened while the prediction of SLEs from DV was substantially strengthened. We found no evidence for ‘reverse causation’ from MD episodes to SLEs. Conclusion The interrelationship between DV and acute adversity in the etiology of MD is complex and temporally dynamic. DV impacts on MD risk both directly and indirectly through selection into high stress environments. Over time, depressive episodes become more autonomous. Both DV and SLEs transmit forward over time and therefore form clear targets for intervention.
Effects of preconditioned plasma collected during the late phase of remote ischaemic preconditioning on ventricular arrhythmias caused by myocardial ischaemia reperfusion in rats

Objective The administration of preconditioned plasma collected during the late phase of preconditioning has been shown to reduce myocardial infarct size. This study aimed to investigate if preconditioned plasma could attenuate ventricular arrhythmias in a rat model in vivo. Methods Eighty rats were randomized to eight groups (10 rats/group). Two groups provided preconditioned or non-preconditioned plasma 48 h after transient limb ischaemia or the control protocol. Six groups of ischaemia-reperfusion (IR) rats received normal saline, non-preconditioned plasma, or preconditioned plasma, respectively, 1 h (groups A1, A2, A3) or 24 h (groups B1, B2, B3) before undergoing myocardial IR. Electrocardiograms were monitored using a BIOPAC system, and the incidence and duration of ventricular tachycardia (VT) and ventricular fibrillation (VF) were analysed. Results No significant differences existed in the incidence and duration of VT or VF among groups A1–A3 or in the incidence and duration of VT among groups B1–B3. However, there was a significantly lower incidence and shorter duration of VF in group B3 rats than in group B1 rats. Conclusion Preconditioned plasma collected during the late phase of preconditioning can reduce the incidence and duration of VF compared with normal saline, suggesting its anti-arrhythmic potential.
Posterior Dynamic Stabilization With Direct Pars Repair via Wiltse Approach for the Treatment of Lumbar Spondylolysis: The Application of a Novel Surgery

Study Design. A retrospective study to evaluate the clinical outcomes of a novel surgical method for treating patients with lumbar spondylolysis. Objective. The aim of this study was to investigate the effectiveness of posterior ISOBAR TTL stabilization of the lumbar spine with direct pars repair using Wiltse approach for the treatment of lumbar spondylolysis with or without slight spondylolisthesis and discuss the indications of this surgery. Summary of Background Data. Surgical treatment of lumbar spondylolysis has yielded relatively good results. However, there are still many limitations of the current surgical methods, including, adjacent level degeneration, restricted indications, and soft tissue damage. Methods. Between August 2010 and January 2013, 13 (9 males and 4 females; mean age: 28.2 yrs), patients with lumbar spondylolysis with or without slight spondylolisthesis underwent posterior ISOBAR TTL stabilization of the lumbar spine, with direct pars repair via Wiltse approach. All patients were followed up for at least 24 months at outpatient visits or telephonically. Pre-operative and postoperative radiological assessments included anteroposterior, lateral and flexion extension radiographs, 3-dimensional reconstruction computed tomography (CT), and magnetic resonance imaging (MRI). Data pertaining to intraoperative blood loss, duration of operation, visual analog score (VAS), Oswestry disability index (ODI) scores, and other assessments were collected. Results. The median follow-up duration was 36 months (range, 24–53 months). Surgery was successful in all patients with no complications; bony fusion of pars was confirmed on CT scan at postoperative 2 years. Significant pain relief was achieved in all patients including those with discogenic pain, those >30 years of age, and those with severe disc degeneration (P < 0.01). Conclusion. We evaluated a new surgical technique for the treatment of patients with spondylolysis with or without slight spondylolisthesis. Besides the good clinical results, the indications for this new surgery are much wider and can potentially overcome the limitations of earlier techniques. Level of Evidence: 4