VoroCrust: Voronoi Meshing Without Clipping.

Polyhedral meshes are increasingly becoming an attractive option with particular advantages over traditional meshes for certain applications. What has been missing is a robust polyhedral meshing algorithm that can handle broad classes of domains exhibiting arbitrary curved boundaries and sharp features. In addition, the power of primal-dual mesh pairs, exemplified by Voronoi-Delaunay meshes, has been recognized as an important ingredient in numerous formulations. The VoroCrust algorithm is the first provably correct algorithm for conforming Voronoi meshing for non-convex and possibly non-manifold domains with guarantees on the quality of both surface and volume elements. A robust refinement process estimates a suitable sizing field that enables the careful placement of Voronoi seeds across the surface circumventing the need for clipping and avoiding its many drawbacks. The algorithm has the flexibility of filling the interior by either structured or random samples, while all sharp features are preserved in the output mesh. We demonstrate the capabilities of the algorithm on a variety of models and compare against state-of-the-art polyhedral meshing methods based on clipped Voronoi cells establishing the clear advantage of VoroCrust output.

Incidence, Pathotyping, and Antibiotic Susceptibility of Avian Pathogenic Escherichia coli among Diseased Broiler Chicks.

A total of 54 broiler flocks during the first two weeks of life was used to investigate the incidence of avian pathogenic E. coli in Egypt; 28 isolates (51.85%) were revealed by colony morphology and biochemical identification which then investigated for their serogroups and only 18/28 isolates were serotyped. The most prevalent serotypes were O115, O142, O158, O55, O125, O114, O27, O20, and O15. By application of polymerase chain reaction (PCR), 83.3% (15/18) of the serotyped isolates were confirmed to be E. coli, and 93.3% (14/15), 46.6% (7/15), and 20% (3/15) of isolates harbored the iss, iutA, and fimH genes, respectively. Virulence testing of the selected 13 APEC isolates on the specific-pathogen-free (SPF) chicks revealed them to be highly virulent (15.4%), moderately virulent (23.1%), and avirulent (61.5%); however, all isolates (100%) were extremely virulent towards SPF embryonated chicken eggs. Antibiotic resistance (100% of isolates (n = 13)) was observed for ampicillin, amoxycillin-clavulanic acid, and tetracyclines, colistin (92.31%; 12/13), doxycycline and spiramycin (84.62%; 11/13), florfenicol (69.23%; 9/13), cefotaxime (61.54%; 8/13), and ciprofloxacin (53.85%; 7/13). The highest percentage of sensitivity (53.85% of isolates; 7/13) was recorded for ofloxacin and enrofloxacin followed by gentamycin (46.15%; 6/13). The results suggest that the diagnosis of APEC with PCR is rapid and more accurate than traditional methods for E. coli identification; moreover, the presence or absence of iss, iutA, and/or fimH genes is not an indicator of in vivo pathogenicity of APEC. Thus, further studies, including a wider range of virulence genes and gene sequencing, are required. In addition, serotyping has no effect on the virulence of APEC.

In Silico Elucidation of the Plausible Inhibitory Potential of Withaferin A of Withania Somnifera Medicinal Herb Against Breast Cancer Targeting Estrogen Receptor.

BACKGROUND: Estrogen Receptors (ER) are members of the nuclear intracellular receptors family. ER once activated by estrogen, it binds to DNA via translocating into the nucleus and regulates the activity of various genes. Withaferin A (WA) - an active compound of a medicinal plant Withania somnifera was reported to be a very effective anti-cancer agent and some of the recent studies has demonstrated that WA is capable of arresting the development of breast cancer via targeting estrogen receptor. OBJECTIVE: The present study is aimed at understanding the molecular level interactions of ER and Tamoxifen in comparison to Withaferin A using In-silico approaches with emphasis on Withaferin A binding capability with ER in presence of point mutations which are causing de novo drug resistance to existing drugs like Tamoxifen. METHODS: Molecular modeling and docking studies were performed for the Tamoxifen and Withaferin A with the Estrogen receptor. Molecular docking simulations of estrogen receptor in complex with Tamoxifen and Withaferin A were also performed. RESULTS: Amino acid residues, Glu353, Arg394 and Leu387 was observed as crucial for binding and stabilizing the protein-ligand complex in case of Tamoxifen and Withaferin-A. The potential of Withaferin A to overcome the drug resistance caused by the mutations in estrogen receptor to the existing drugs such as Tamoxifen was demonstrated. CONCLUSION: In-silico analysis has elucidated the binding mode and molecular level interactions which are expected to be of great help in further optimizing Withaferin A or design / discovery of future breast cancer inhibitors targeting estrogen receptor.

Effect of Varying Levels of Chromium Propionate on Growth Performance and Blood Biochemistry of Broilers.

The objective of this work was to evaluate the effects of varying levels of chromium propionate on blood biochemistry and growth performance of broilers (1-35 days). Five diets were formulated by using chromium propionate with inclusion levels of 0, 200, 400, 800 and 1600 ppb. A total of 300 broilers were divided into 5 groups with 6 replicates of 10 birds in each under completely randomized design. The starter feed intake remained unaffected (p > 0.05) whereas finisher and overall feed intake was different (p < 0.05) among different experimental groups. Feed conversion ratio and weight gain in starter, finisher and overall improved significantly (p < 0.05) with the increasing levels of chromium propionate. Blood glucose was decreased (p < 0.05) with increasing dietary chromium level. Chromium supplementation did not affect antibodies titers against NDV and AIV-H9. Neither live, hilal, after skin removal, eviscerated, chest weight and legs with shanks weight nor liver and heart weights were affected (p > 0.05) while gizzard weight reduced significantly (p < 0.05) due to supplementation of chromium. On the basis of results, it may be concluded that chromium propionate supplementation improved weight gain and FCR and reduced blood glucose. However, better performance and weight gain may be achieved if chromium propionate is added at the rate of 400 ppb in broiler diets.

Outcomes of Surgical Ablation in Patients With Atrial Fibrillation Undergoing Cardiac Surgeries.

BACKGROUND: Surgical ablation procedure is commonly performed in patients with atrial fibrillation (AF) undergoing cardiac surgeries; however, the evidence regarding its impact on in-hospital cardiovascular outcomes is controversial. METHODS: We queried the Nationwide Inpatient Sample Database for patients with AF who underwent cardiac surgeries from 1998 to 2013. We performed a propensity-score matching including 21 various baseline characteristics to compare those who underwent surgical ablation with those who had not. RESULTS: A total of 47,964 hospitalizations were included in our final analysis. On propensity matching, 23,975 were in the surgical ablation group and 23,990 in the control group. The primary outcome of in-hospital mortality was lower in the surgical ablation group compared with the control group (3.6% versus 4.2%, p < 0.001). The surgical ablation group was associated with lower in-hospital cerebrovascular accident (2.0% versus 2.8%, p < 0.001), cardiogenic shock (2.6% versus 3.6%, p < 0.001), use of intraaortic balloon pump (5.1% versus 5.8%, p = 0.001), and shorter length of hospital stay (12.3 ± 10.1 versus 12.5 ± 10.3 days, p = 0.008). There was no difference between the surgical ablation and control groups in the incidence of cardiac tamponade (0.4% versus 0.3%, p = 0.296). The surgical ablation group was associated with a higher rate of complete heart block (5.2% versus 4.3%, p < 0.001) and permanent pacemaker insertion (8.6% versus 8.0%, p = 0.01). CONCLUSIONS: In this large analysis of almost 50,000 patients with AF undergoing cardiac surgery, surgical ablation appears to be safe in the short term. Future studies should focus on evaluating the long-term effectiveness of this procedure.

Commiphora molmol protects against methotrexate-induced nephrotoxicity by up-regulating Nrf2/ARE/HO-1 signaling.

Commiphora molmol possesses multiple therapeutic benefits against various diseases; however, its protective role against methotrexate (MTX) renal toxicity has not been previously investigated. MTX is a dihydrofolate reductase inhibitor that can induce acute kidney injury (AKI). This study evaluated the in vitro antioxidant activity and the protective effect of C. molmol resin extract against MTX-induced oxidative stress, inflammation and renal injury. Male Wistar rats received 125 and 250 mg/kg C. molmol resin extract for 15 days and a single injection of MTX at day 16. C. molmol showed a radical scavenging activity against DPPH, superoxide and nitric oxide (NO) radicals. Rats received MTX showed renal injury evidenced by the significantly elevated serum creatinine and urea, and the histological alterations. The kidney of MTX-induced rats exhibited increased lipid peroxidation, NO, NF-κB and pro-inflammatory cytokines. Pre-treatment with C. molmol prevented MTX-induced kidney injury and attenuated oxidative stress and inflammation. C. molmol down-regulated Bax and enhanced the activity and expression of the antioxidant defenses. Furthermore, the expression of Bcl-2, Nrf2, NQO-1 and HO-1 was down-regulated in the kidney of MTX-induced rats. Pre-treatment with C. molmol resin up-regulated Bcl-2 and activated Nrf2/HO-1 signaling in the kidney of MTX-induced rats. In conclusion, C. molmol resin provided protection against MTX-induced AKI via activation of Nrf2 signaling and mitigation of oxidative stress.

Sampling Conditions for Conforming Voronoi Meshing by the VoroCrust Algorithm.

We study the problem of decomposing a volume with a smooth boundary into a collection of Voronoi cells. Unlike the dual problem of conforming Delaunay meshing, a principled solution to this problem for generic smooth surfaces remained elusive. VoroCrust leverages ideas from weighted α-shapes and the power crust algorithm to produce unweighted Voronoi cells conforming to the surface, yielding the first provably-correct algorithm for this problem. Given a κ-sparse ε-sample, we work with the balls of radius δ times the local feature size centered at each sample. The corners of the union of these balls on both sides of the surface are the Voronoi sites and the interface of their cells is a watertight surface reconstruction embedded in the dual shape of the union of balls. With the surface protected, the enclosed volume can be further decomposed by generating more sites inside it. Compared to clipping-based algorithms, VoroCrust cells are full Voronoi cells, with convexity and fatness guarantees. Compared to the power crust algorithm, VoroCrust cells are not filtered, are unweighted, and offer greater flexibility in meshing the enclosed volume by either structured or randomly genenerated samples.

Allelic variation of melanocortin-1 receptor locus in Saudi indigenous sheep exhibiting different color coats.

OBJECTIVE: This study was designed to characterize the DNA polymorphisms of the melanocortin-1 receptor (MC1R) gene in indigenous Saudi Arabian sheep breeds exhibiting different color coats, along with individuals of the Sawaknee breed, an exotic sheep imported from Sudan. METHODS: The complete coding region of MC1R gene including parts of 3' and 5' untranslated regions was amplified and sequenced from three the indigenous Saudi sheep; Najdi (generally black, n = 41), Naeimi (generally white with brown faces, n = 36) and Herri (generally white, n = 18), in addition to 13 Sawaknee sheep. RESULTS: Five single nucleotide polymorphisms (SNPs) were detected in the MC1R gene: two led to nonsynonymous mutations (c.218 T>A, p.73 Met>Lys and c.361 G>A, p.121 Asp>Asn) and three led to synonymous mutations (c.429 C>T, p.143 Tyr>Tyr; c.600 T>G, p.200 Leu>Leu, and c.735 C>T, p.245 Ile>Ile). Based on these five SNPs, eight haplotypes representing MC1R Ed and E+ alleles were identified among the studied sheep breeds. The most common haplotype (H3) of the dominant Ed allele was associated with either black or brown coat color in Najdi and Sawaknee sheep, respectively. Two other haplotypes (H6 and H7) of Ed allele, with only the nonsynonymous mutation A218T, were detected for the first time in Saudi indigenous sheep. CONCLUSION: In addition to investigating the MC1R allelic variation in Saudi indigenous sheep populations, the present study supports the assumption that the two independent nonsynonymous Met73Lys and Asp121Asn mutations in MC1R gene are associated with black or red coat colors in sheep breeds.

Disk Density Tuning of a Maximal Random Packing.

We introduce an algorithmic framework for tuning the spatial density of disks in a maximal random packing, without changing the sizing function or radii of disks. Starting from any maximal random packing such as a Maximal Poisson-disk Sampling (MPS), we iteratively relocate, inject (add), or eject (remove) disks, using a set of three successively more-aggressive local operations. We may achieve a user-defined density, either more dense or more sparse, almost up to the theoretical structured limits. The tuned samples are conflict-free, retain coverage maximality, and, except in the extremes, retain the blue noise randomness properties of the input. We change the density of the packing one disk at a time, maintaining the minimum disk separation distance and the maximum domain coverage distance required of any maximal packing. These properties are local, and we can handle spatially-varying sizing functions. Using fewer points to satisfy a sizing function improves the efficiency of some applications. We apply the framework to improve the quality of meshes, removing non-obtuse angles; and to more accurately model fiber reinforced polymers for elastic and failure simulations.

All-Hex Meshing of Multiple-Region Domains without Cleanup.

In this paper, we present a new algorithm for all-hex meshing of domains with multiple regions without post-processing cleanup. Our method starts with a strongly balanced octree. In contrast to snapping the grid points onto the geometric boundaries, we move points a slight distance away from the common boundaries. Then we intersect the moved grid with the geometry. This allows us to avoid creating any flat angles, and we are able to handle two-sided regions and more complex topologies than prior methods. The algorithm is robust and cleanup-free; without the use of any pillowing, swapping, or smoothing. Thus, our simple algorithm is also more predictable than prior art.