Bio-inspired Surface Texture Fluid Drag Reduction using Large Eddy Simulation

Skin friction drag can be reduced through the application of bio-inspired riblet surfaces. Numerical simulations were performed using Large Eddy Simulation (LES) to investigate the effect of using riblets on reducing skin friction drag. In this study, three different riblet configurations were used; scalloped, sawtooth and a new design, hybrid, riblet. To validate the effect of using the proposed hybrid riblet design compared with other riblets used in the literature; before applying to complex geometries, they were initially applied to a flat plate in parallel arrangement. Results showed skin friction coefficient reduction of 14% using the proposed hybrid riblet. This reduction was 9.2 times and 1.2 times more compared to sawtooth and scalloped configurations, respectively. The hybrid riblet was then applied partially and fully to NACA 0012 airfoil. Skin friction coefficient reduction of 34.5% was obtained when the hybrid riblet fully applied on the airfoil surface. Furthermore, the Convergent-Divergent (C-D) arrangement was studied, where the riblets were placed fully on the NACA 0012 and aligned with a yaw angle with respect to the flow direction. The convergent lines are inspired by the sensory part of the shark skin, whereas the divergent lines or herringbone are found on the bird feather. The two different riblet configurations, sawtooth and hybrid were modeled with the C-D arrangement and the hybrid riblet with C-D arrangement contributed to higher skin friction coefficient reduction, 34.5%, than the sawtooth riblet shape, 26.75%. Moreover, the C-D arrangement was compared to the parallel arrangement and shown that the C-D arrangement increased the lift coefficient (cl) of the airfoil, the flow separation was delayed and the overall performance of the airfoil was enhanced

Leishmanicidal Activity of Films Containing Paromomycin and Gentamicin Sulfate both In Vitro and In Vivo

Background: Based on the efficacy of paromomycin ointment and recent ongoing clinical trials of combination of paromomycin and gentamicin, a new physical form of films of the paromomy­cin and gentamicin was prepared and anti-Leishmania activities of the prepared films were as­sessed in vitro and in vivo.Methods: Paromomycin 15% and gentamicin 0.5% was incorporated in a film using ethyl cellu­lose and HPMC (Hydroxyl Propyl Methyl Cellulose). In order to assess the drug release and anti-Leishmania activities of the preparation, a clone L. major parasite was established using a set of modified NNN medium without overlay liquid layer. Therapeutic effects of the films were evalu­ated using Balb/c mice model. The mice were inoculated with 2×106 L. major promastigotes (MRHO/IR/75/ER) and then when the lesions developed the mice were randomly divided in 3 groups, 10 mice per group, and treated with either perpetrated films or placebo for 28 days or left untreated.Results: Growth inhibition of cloned promastigotes showed that the films have enough releasing capacity and in vivo system, the films containing paromomycin and gentamicin was able to re­duce the lesion size and induced complete cure in 80% of the mice but relapse was seen in 60% of the cured mice and overall 50% cure rate was seen during 20 weeks period of the study.Conclusion: It seems that the prepared films might be further used in human clinical trials

Mycobiota and aflatoxin B1 contamination of rainbow trout (Oncorhinchus mykiss) feed with emphasis to Aspergillus section Flavi

In the present study, mycobiota and natural occurrence of aflatoxin B1 (AFB1) in pellet feed and feed ingredients used in a feed manufacturing plant for rainbow trout nutrition was investigated. The samples were cultured on the standard isolation media for 2 weeks at 28 ºC. Identification of fungal isolates was implemented based on the macro- and microscopic morphological criteria. AFB1 was detected using high performance liquid chromatography (HPLC). Based on the results obtained, a total of 109 fungal isolates were identified of which Aspergillus was the prominent genus (57.0%), followed by Penicillium (12.84%), Absidia (11.01%) and Pseudallscheria (10.10%). The most frequent Aspergillus species was A. flavus (60.66%) isolated from all feed ingredients as well as pellet feed. Among 37 A. flavus isolates, 19 (51.35%) were able to produce AFB1 on YES broth in the range of 10.2 to 612.8 µg/g fungal dry weight. HPLC analysis of trout feed showed that pellet feed and all feed ingredients tested except gluten were contaminated with different levels of AFB1 in the range of 1.83 to 67.35 µg/kg. Unacceptable levels of AFB1 were reported for feed including soybean, fish meal and wheat. These results indicate the importance of AF contamination of trout feed in amounts higher than the acceptable level as a risk factor for fish farming production

Transcription of toll-like receptors 2, 3, 4 and 9, FoxP3 and Th17 cytokines in a susceptible experimental model of canine Leishmania infantum infection

Canine leishmaniosis (CanL) due to Leishmania infantum is a chronic zoonotic systemic disease resulting from complex interactions between protozoa and the canine immune system. Toll-like receptors (TLRs) are essential components of the innate immune system and facilitate the early detection of many infections. However, the role of TLRs in CanL remains unknown and information describing TLR transcription during infection is extremely scarce. The aim of this research project was to investigate the impact of L. infantum infection on canine TLR transcription using a susceptible model. The objectives of this study were to evaluate transcription of TLRs 2, 3, 4 and 9 by means of quantitative reverse transcription polymerase chain reaction (qRT-PCR) in skin, spleen, lymph node and liver in the presence or absence of experimental L. infantum infection in Beagle dogs. These findings were compared with clinical and serological data, parasite densities in infected tissues and transcription of IL-17, IL-22 and FoxP3 in different tissues in non-infected dogs (n = 10), and at six months (n = 24) and 15 months (n = 7) post infection. Results revealed significant down regulation of transcription with disease progression in lymph node samples for TLR3, TLR4, TLR9, IL-17, IL-22 and FoxP3. In spleen samples, significant down regulation of transcription was seen in TLR4 and IL-22 when both infected groups were compared with controls. In liver samples, down regulation of transcription was evident with disease progression for IL-22. In the skin, upregulation was seen only for TLR9 and FoxP3 in the early stages of infection. Subtle changes or down regulation in TLR transcription, Th17 cytokines and FoxP3 are indicative of the silent establishment of infection that Leishmania is renowned for. These observations provide new insights about TLR transcription, Th17 cytokines and Foxp3 in the liver, spleen, lymph node and skin in CanL and highlight possible markers of disease susceptibility in this model

Chemical profiles and cytotoxic activities of essential oils from six species of Baccharis subgenus Coridifoliae (Asteraceae).

This article augments the current know ledge about the chemical-biological properties of Baccharis subgenus Coridifoliae and discusses the therapeutic potentials of these economically unexploited plants

Whole Transcriptome-Based Skin Virome Profiling in Typical Epidermodysplasia Verruciformis Reveals α-, β-, and γ-HPV Infections

HPVs are DNA viruses include approximately 450 types that are classified into 5 genera (α-, β-, γ-, μ-, and ν-HPV). The γ- and β-HPVs are present in low copy numbers in healthy individuals; however, in patients with an inborn error of immunity, certain species of β-HPVs can cause epidermodysplasia verruciformis (EV), manifesting as recalcitrant cutaneous warts and skin cancer. EV presents as either typical or atypical. Manifestations of typical EV are limited to the skin and are caused by abnormal keratinocyte-intrinsic immunity to β-HPVs due to pathogenic sequence variants in TMC6, TMC8, or CIB1. We applied a transcriptome-based computational pipeline, VirPy, to RNA extracted from normal-appearing skin and wart samples of patients with typical EV to explore the viral and human genetic determinants. In 26 patients, 9 distinct biallelic mutations were detected in TMC6, TMC8, and CIB1, 7 of which are previously unreported to our knowledge. Additionally, 20 different HPV species, including 3 α-HPVs, 16 β-HPVs, and 1 γ-HPV, were detected, 8 of which are reported here for the first time to our knowledge in patients with EV (β-HPV-37, -47, -80, -151, and -159; α-HPV-2 and -57; and γ-HPV-128). This study expands the TMC6, TMC8, and CIB1 sequence variant spectrum and implicates new HPV subtypes in the pathogenesis of typical EV

Lowering the error floor of LDPC codes using multi-step quantization

A multi-step scheme is proposed for the input quantization of message-passing decoders for low-density parity-check (LDPC) codes. The proposed scheme, which is applicable to both regular and irregular codes, lowers the error floor significantly at the cost of small increase in complexity, memory and latency

Fast and accurate error floor estimation of quantized iterative decoders for variable-regular LDPC codes

In this letter, we propose a fast and accurate technique to estimate the error floor of variable-regular low-density parity-check (LDPC) codes under quantized iterative decoding algorithms. The technique, which is based on enumerating the dominant elementary trapping sets of the code, provides significant improvement over existing methods in terms of speed and accuracy

FPGA implementation of variants of min-sum algorithm

This paper presents the FPGA implementation of a number of popular decoding algorithms for a regular rate-1/2 low density parity check code with block length 504 bits. The so-called min-sum (MS) algorithm and two of its variants, known as MS with successive relaxation (SR-MS) and MS with unconditional correction (MS-UC), are implemented. We implement the algorithms on a Xilinx XC2VP100 FPGA device with 4-bit quantization. We show that for MS-UC, the circuit utilization increases by about 2% compared to standard MS and that the throughput is the same as that of MS. For SR-MS, the device utilization is increased by about 26% and the throughput is decreased by approximately 20% compared to standard MS. While the throughput and the area and power consumption of our implementation is comparable to the most recent FPGA implementations of LDPC decoders, ours is the first attempt at implementing an iterative decoding algorithm with memory (SR-MS)