A comparison of the finite difference and finite element methods for heat transfer calculations

The finite difference method and finite element method for heat transfer calculations are compared by describing their bases and their application to some common heat transfer problems. In general it is noted that neither method is clearly superior, and in many instances, the choice is quite arbitrary and depends more upon the codes available and upon the personal preference of the analyst than upon any well defined advantages of one method. Classes of problems for which one method or the other is better suited are defined

Interactive computation of radiation view factors

The development of a pair of computer programs to calculate the radiation exchange view factors is described. The surface generation program is based upon current graphics capabilities and includes special provisions which are unique to the radiation problem. The calculational program uses a combination of contour and double area integration to permit consideration of radiation with obstruction surfaces. Examples of the surface generation and the calculation are given

Heterostigmatic mites (Acari: Heterostigmatina) associated with insects in northwestern Iran

During a faunistic survey on heterostigmatic mites (Acari: Heterostigmatina: Caraboacaridae, Podapolipidae, Microdispidae, Neopygmephoridae), associated with insects in northwestern Iran, eight species were identified. The species Eutarsopolipus harpali Khaustov & Husband, 2004 (Podapolipidae) and Petalomium pseudomyrmecophilus Mahunka, 1970 (Neopygmephoridae) are here recorded for the first time from Iran and Asia. The six remaining species are as follows: Caraboacarus stammeri Krczal, 1959 (Caraboacaridae), Coccipolipus macfarlanei Husband, 1972 (Podapolipidae), Premicrodispus rackae Khaustov, 2006 (Microdispidae), Parapygmephorus magnisetosus Khaustov & Zalozhnaya, 2011, Acinogaster microchaetosus (Sevastianov, 1967) and Petalomium gottrauxi Mahunka, 1977 (Neopygmephoridae). We have also provided a new host record along with the world distribution of the mites

Pruning Edge Research with Latency Shears

Edge computing has gained attention from both academia and industry by pursuing two significant challenges: 1) moving latency critical services closer to the users, 2) saving network bandwidth by aggregating large flows before sending them to the cloud. While the rationale appeared sound at its inception almost a decade ago, several current trends are impacting it. Clouds have spread geographically reducing end-user latency, mobile phones? computing capabilities are improving, and network bandwidth at the core keeps increasing. In this paper, we scrutinize edge computing, examining its outlook and future in the context of these trends. We perform extensive client-to-cloud measurements using RIPE Atlas, and show that latency reduction as motivation for edge is not as persuasive as once believed; for most applications the cloud is already 'close enough' for majority of the world's population. This implies that edge computing may only be applicable for certain application niches, as opposed to a general-purpose solution.Peer reviewe

ShortRead: a bioconductor package for input, quality assessment and exploration of high-throughput sequence data

Summary: ShortRead is a package for input, quality assessment, manipulation and output of high-throughput sequencing data. ShortRead is provided in the R and Bioconductor environments, allowing ready access to additional facilities for advanced statistical analysis, data transformation, visualization and integration with diverse genomic resources

Beyond Spheroids and Discs: Classifications of CANDELS Galaxy Structure at 1.4 < z < 2 via Principal Component Analysis

Important but rare and subtle processes driving galaxy morphology and star-formation may be missed by traditional spiral, elliptical, irregular or S\'ersic bulge/disk classifications. To overcome this limitation, we use a principal component analysis of non-parametric morphological indicators (concentration, asymmetry, Gini coefficient, $M_{20}$, multi-mode, intensity and deviation) measured at rest-frame $B$-band (corresponding to HST/WFC3 F125W at 1.4 $10^{10} M_{\odot}$) galaxy morphologies. Principal component analysis (PCA) quantifies the correlations between these morphological indicators and determines the relative importance of each. The first three principal components (PCs) capture $\sim$75 per cent of the variance inherent to our sample. We interpret the first principal component (PC) as bulge strength, the second PC as dominated by concentration and the third PC as dominated by asymmetry. Both PC1 and PC2 correlate with the visual appearance of a central bulge and predict galaxy quiescence. PC1 is a better predictor of quenching than stellar mass, as as good as other structural indicators (S\'ersic-n or compactness). We divide the PCA results into groups using an agglomerative hierarchical clustering method. Unlike S\'ersic, this classification scheme separates compact galaxies from larger, smooth proto-elliptical systems, and star-forming disk-dominated clumpy galaxies from star-forming bulge-dominated asymmetric galaxies. Distinguishing between these galaxy structural types in a quantitative manner is an important step towards understanding the connections between morphology, galaxy assembly and star-formation.Comment: 31 pages, 24 figures, accepted for publication in MNRA

Cytotoxicity, antifungal, antioxidant, antibacterial and photodegradation potential of silver nanoparticles mediated via Medicago sativa extract

The biosynthesis of metallic nanoparticles is on a sharp rise as they have growing applications in environmental and biomedical sciences. This study reports an eco-friendly and cost-effective methodology for synthesizing biogenic silver nanoparticles (AgNPs) using the extract of Medicago sativa (M. sativa) cultivated in South Khorasan. The parameters used in the synthesis process were optimized to obtain uniformly distributed AgNPs in suitable sizes. The morphological, structural, and bonding characteristics of M. sativa extract-based AgNPs (MSE-AgNPs) were explored using FTIR, FESEM, EDS, TEM, XRD, UV–Vis, and DLS techniques. UV–Vis spectroscopy confirmed the formation of MSE-AgNPs by observing the typical surface plasmon resonance (SPR) peak at 419 nm. XRD, FESEM, TEM, and DLS analyses confirmed the formation of face-centered cubic (fcc) crystalline structure, spherical/elliptical morphology, the average particle size of 15–35 nm, and highly stable MSE-AgNPs. Green synthesized MSE-AgNPs indicated a significant antioxidant activity (78%) compared to M. sativa extract (32%). As such, the synthesized MSE-AgNPs revealed a potential antioxidant activity towards the DPPH radicals. The biologically synthesized MSE-AgNPs exhibited highly potential antibacterial and antifungal activities against Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Staphylococcus epidermidis, Enterococcus faecalis, Staphylococcus aureus, and Candida albicans with the minimum inhibitory concentration (MIC) values of 62.5, 125, 125, 1000, 125, 1000, and 31.25 µg/mL, respectively. In vitro cytotoxicity of the MSE-AgNPs against human fibroblast (HF) cells indicated a dose–response activity (with IC50 value of 18 µg/mL). Moreover, the AgNPs revealed efficient photocatalytic degradation of thymol blue (TB) as an anionic dye and malachite green (MG) as a cationic dye under sunlight and UV irradiations. Up to 94.37% and 90.12% degradation rates were obtained for MG and TB within only 100 min of UV irradiation. These observations signify that synthesized MSE-AgNPs can have great potential for biological and environmental applications

Small RNA Profile in Moso Bamboo Root and Leaf Obtained by High Definition Adapters

Moso bamboo (Phyllostachy heterocycla cv. pubescens L.) is an economically important fast-growing tree. In order to gain better understanding of gene expression regulation in this important species we used next generation sequencing to profile small RNAs in leaf and roots of young seedlings. Since standard kits to produce cDNA of small RNAs are biased for certain small RNAs, we used High Definition adapters that reduce ligation bias. We identified and experimentally validated five new microRNAs and a few other small non-coding RNAs that were not microRNAs. The biological implication of microRNA expression levels and targets of microRNAs are discussed

Mayday SeaSight: Combined Analysis of Deep Sequencing and Microarray Data

Recently emerged deep sequencing technologies offer new high-throughput methods to quantify gene expression, epigenetic modifications and DNA-protein binding. From a computational point of view, the data is very different from that produced by the already established microarray technology, providing a new perspective on the samples under study and complementing microarray gene expression data. Software offering the integrated analysis of data from different technologies is of growing importance as new data emerge in systems biology studies. Mayday is an extensible platform for visual data exploration and interactive analysis and provides many methods for dissecting complex transcriptome datasets. We present Mayday SeaSight, an extension that allows to integrate data from different platforms such as deep sequencing and microarrays. It offers methods for computing expression values from mapped reads and raw microarray data, background correction and normalization and linking microarray probes to genomic coordinates. It is now possible to use Mayday's wealth of methods to analyze sequencing data and to combine data from different technologies in one analysis

Prevalence of Cannabis Lifetime Use in Iranian High School and College Students: A Systematic Review, Meta-Analyses,and Meta-Regression

Cannabis is the most widely used substance in the world. This study aimed to estimate the prevalence of cannabis lifetime use (CLU) in high school and college students of Iran and also to determine factors related to changes in prevalence. A systematic review of literature on cannabis use in Iran was conducted according to MOOSE guideline. Domestic scientific databases, PubMed/Medline, ISI Web of Knowledge, and Google Scholar, relevant reference lists, and relevant journals were searched up to April, 2014. Prevalences were calculated using the variance stabilizing double arcsine transformation and confidence intervals (CIs) estimated using the Wilson method. Heterogeneity was assessed by Cochran's Q statistic and I-2 index and causes of heterogeneity were evaluated using meta-regression model. In electronic database search, 4,000 citations were retrieved, producing a total of 33 studies. CLU was reported with a random effects pooled prevalence of 4.0 (95 CI = 3.0 to 5.0). In subgroups of high school and college students, prevalences were 5.0 (95 CI = 3.0 to -7.0) and 2.0 (95 CI = 2.0 to -3.0), respectively. Meta-regression model indicated that prevalence is higher in college students (beta = 0.089, p < .001), male gender (beta = 0.017, p < .001), and is lower in studies with sampling versus census studies (beta = -0.096, p < .001). This study reported that prevalence of CLU in Iranian students are lower than industrialized countries. In addition, gender, level of education, and methods of sampling are highly associated with changes in the prevalence of CLU across provinces