Burst Strength of NPS30 Steel Pipes with Dent-Crack Defect

Pipeline is the common mode for transporting oil, gas, and various petroleum products. Structural integrity of oil and gas transmission pipelines is often threatened by damages such as dent, corrosion, crack, gouge, or any combination of these damages. Such a damage may lead to structural failure in a field pipeline. One of combined defects is dent-crack defect which is a dent defect that contains a crack defect within the dent. Hence, the pipeline operator becomes concerned about the performance and safety of the linepipe if a pipe wall is subject to a dent-crack defect. Research work using full-scale tests and finite element method was undertaken at the Centre for Engineering Research in Pipelines, University of Windsor to study the influence of various internal pressures, diameter-to-thickness ratios, dent depths, crack lengths, crack depths, crack locations, and pipe steel grade on the structural behaviour and the burst strength of NPS30 (30 in diameter) and X70 and X55 grade pipes when a dent-crack defect is developed. This dissertation discusses the experimental and numerical results obtained from this study with the conclusions drawn

The effect of created hemolymph apoptosis on WSSV Gamma-vaccinated shrimp, Litopenaeus vannamei in WSSV disease control

White spot syndrome virus (WSSV) is the causative agent responsible for huge-shrimp viral epidemics in shrimp farms throughout the world. Our study was aimed to determine the effect of WSSV Gamma-vaccinated Litopenaeus vannamei on the occurrence of apoptosis. One thousand and twenty PL15 were randomly distributed among 2 treatments and two control groups. Gamma-Vaccinated shrimp and non-Gamma-vaccinated ones were our treated and untreated groups. Based on our results significant differences (p<0.05) were observed in survival percent between vaccinated-exposed group (82.33±2.51) and non-vaccinated exposed group (26.00±10.00). It is concluded that apoptosis can be a helpful process in enhancing the immune response in shrimp especially against WSSV

Effects of temperature on hematological and histopathological changes and survival rate of juvenile Fenneropenaeus vannamei experimentally challenged to White Spot Virus

Many shrimp farmers were suffering from White Spot Disease (WSD) onset in last decades. Oscillation of environmental factors could lead mortality in susceptible hosts. Our study was aimed to investigate the effect of different temperatures on juvenile Fenneropenaeus vannamei experimentally exposed to White Spot Virus (WSV). Five hundred and forty juveniles were distributed among 3 treatments in triplicates, 22, 25 and 30°C and experimentally WSV were injected in the shrimps. Our results showed mortality started at 36 h post inoculation (hpi) in the treatment at 25°C (T25), meanwhile the mean value of mortality percent at 54 hpi in T25 (71.10±17.35) showed the significant difference (p=.045) with T22 (3.33±3.33) and T30 (Not Observed, NO.). Our results suggest that in site selection, in primary stage of farm designing, water temperature at more than 29°C, should be considered as key environmental factor. This finding can lead us that why the White Spot Disease occurred with high mortality in some area when the days of shrimp culture were prolonged until mid autumn

Effects of aflatoxin B1 on growth performance, health indices, phagocytic activity and histopathological alteration in Fenneropenaeus indicus

Mycotoxins contamination of feedstuff for aquatic animals is common in regions with humid tropical conditions. In this study Indian white shrimp, Fenneropenaeus indicus, (11.79 ± 1.76 g) were fed with diets containing 0, 20, 50, 100, 200, 400, 800 and 1600 ppb levels of aflatoxin B1 (AFLB1) for 8 weeks. Final weight, aflatoxin B1 residue (2-week intervals), Total Hemocyte Count (THC), Total Plasma Protein (TPP), Phagocytic Activity (PA), Survival rate (4-week intervals) were determined. Histopathological alterations in hepatopancreas, midgut and muscle tissues were studied at the end of 4 and 8 weeks. Shrimps fed with the 1600, 800 and 400 ppb concentrations of AFLB1 exhibited slow growth, and more reddish discoloration disseminated over the body at 4th week. Growth parameters, survival rate and health indices (THC, TPP) of F. indicus, are affected by the different doses of AFLB1 in diets. At the end of 8th week, doses of AFLB1 in the diets showed negative correlation to final weight, survival rate, THC and TPP (r = - 0.312, -0.603, -0.237 and - 0.649 at P<0.001, respectively). Moreover, significant histopathological alterations in the hepatopancreas, midgut and muscle tissues of exposed shrimps to different levels of AFLB1 were observed and these alterations are obviously indicated by changes in the health indexes (THC and TPP)

Dietary Administration of Yeast β 1,3 1,6 Glucan on Immunity and Survival Rate of White Indian Shrimp, Fennerpenaeus indicus Challenged with White Spot Syndrome Disease

The potency of dietary β 1,3 1,6 glucan (BG), derived from Saccharomyces cerevisiae, in stimulating the non-specific immunity of white Indian shrimp, Fennerpenaeus indicus (Milne-Edwards, 1837) and improving its resistance to white spot syndrome disease were investigated. F. indicus (11.32±1.20 g) were fed for 20 days on a series of treatment diets containing graded levels of BG (blank control, 0 as control, 2, 10, 20 g kg-1 feed) and were then challenged by injection of WSSV virus. Total haemocyte count (THC), total plasma protein (TPP), phagocytic activity (PA) and Bacterial Clearance activity (BC) were measured at days 0, 7, 14, 21 after BG feeding, and shrimp survival rate was also recorded daily after challenge. THC, TPP, PA and BC of the 10 and 20 g kg-1 BG treatments were significantly higher (P&lt;0.05) by day 14 than control and 2 g kg-1 treatment shrimp. Survival rate of shrimp fed with the diet containing 10 and 20 g kg-1 BG after 21 days, were 53.32±5.77 and 48.32±5.77%, respectively. Accordingly, oral administration of BG at an optimal level of 10 g kg-1 diet for 20 days efficaciously stimulate the immune defense and improve the survival rate of WSV-infected F. indicus

Effect of hot-water extract of brown seaweed Sargassum glaucescens via immersion route on immune responses of Fenneropenaeus indicus

The development of shrimp aquaculture, in spite of its global necessity, is largely at stake as significant ecological and pathological problems are increasing in the vast majority of the shrimp producing countries. Shrimp immunology is a key element in establishing strategies for controlling diseases in shrimp aquaculture. The total haemocyte count (THC), differential haemocyte count (DHC), total plasma protein (TPP), Phagocytic activity (PA), bacterial clearance efficiency (BCE) and bactericidal activity (BE) were examined when the F. indicus shrimps (11.32±1.20 g) were immersed in seawater (39 ppt and 25 ± 1 ºC) containing hot-water extracts of brown alga Sargassum glaucescens at 100, 300 and 500 mg/l. These parameters increased significantly (p < 0.05) when the shrimp were immersed in seawater containing hot-water extracts at 100 mg/l after 3h and 300 and 500 mg/l after 2 h. F. indicus shrimps that were immersed in hot-water extracts at 300 and 500 mg/l had increased phagocytic activity and clearance efficiency to Vibrio spp. after 2 hours. But bactericidal activity increased significantly after 1 hour in the same concentrations

Effects of light regimes on growth and survival of Penaeus semisuleatus

We investigated the possible effects of light regimes on growth and survival rate of juvenile shrimp Penaeus semisuicants cultured in Bushehr Province, southern Iran. Five light regimes each with three replications were applied for 30 days. The treatments were 24 1 0, 18 / 6, 12 1 12, 6 1 18 and 0 124 hours of light and darkness. We found that the treatment 12 7 12 hours of light and darkness was better than 18 1 6 and significantly superior to other treatments (P<0.05). The lowest growth rate was seen in the treatment 24 / 0 (P<0.001 ). We did not find a significant difference in the survival rate of the shrimps cultured in the light and darkness treatments (P<0.05)

Improvement and monitoring of health, pollutants and quality of water

This study was a part of the national big plan of "Attain to technical knowledge of specific pathogen free shrimp production and cut off to dependence on foreign products. "Shrimp aquaculture as one of the most important activities in the world and Iran is expanding. Bacteria and fungi of the most common infectious agents causing diseases are in the hatchery and shrimp. The most important bacteria causing diseases in the hatcheries and shrimp Farms, bacteria are Vibrionaceae family. The fungi can be identified as Fusarium, Mucor, Cladosporium, Aspergillus, Penicillium and yeast. Utilized of water supply system in this project for breeding and reproduction of shrimp is a controlled system. This system acts as a part of biological security. Incoming water before the utilization was monitored for the total bacteria count, fungi and as well as Vibrionaceae family, each 15 days. If contamination is too predictable, additional tests and necessary treatments were carried out to improve the quality of the water. The water, after use in the system and after passing through the filtration system, was guided out. The frequencies of water and sediment sampling were once per month. The water samples for analysis of heavy metals and PAHs were fixed by HNO3 and H2SO4 (pH0.05). There were 17 compounds of PAHs detected in the samples. The samples were calculated using (low molecular/high molecular) PAHs ratio (LMW/HMW) to determine the sources of PAHs. The value of less than 1 is the pyrolytic sources and more than 1, consist of petrogenic sources. In this research LMW/HMW ratio was less than one. On the other hand PAHs of sediments had pyrolytic sources

Augmented and virtual reality in spine surgery, current applications and future potentials

BACKGROUND CONTEXT: The field of artificial intelligence (AI) is rapidly advancing, especially with recent improvements in deep learning (DL) techniques. Augmented (AR) and virtual reality (VR) are finding their place in healthcare, and spine surgery is no exception. The unique capabilities and advantages of AR and VR devices include their low cost, flexible integration with other technologies, user-friendly features and their application in navigation systems, which makes them beneficial across different aspects of spine surgery. Despite the use of AR for pedicle screw placement, targeted cervical foraminotomy, bone biopsy, osteotomy planning, and percutaneous intervention, the current applications of AR and VR in spine surgery remain limited. PURPOSE: The primary goal of this study was to provide the spine surgeons and clinical researchers with the general information about the current applications, future potentials, and accessibility of AR and VR systems in spine surgery. STUDY DESIGN/SETTING: We reviewed titles of more than 250 journal papers from google scholar and PubMed with search words: augmented reality, virtual reality, spine surgery, and orthopaedic, out of which 89 related papers were selected for abstract review. Finally, full text of 67 papers were analyzed and reviewed. METHODS: The papers were divided into four groups: technological papers, applications in surgery, applications in spine education and training, and general application in orthopaedic. A team of two reviewers performed paper reviews and a thorough web search to ensure the most updated state of the art in each of four group is captured in the review. RESULTS: In this review we discuss the current state of the art in AR and VR hardware, their preoperative applications and surgical applications in spine surgery. Finally, we discuss the future potentials of AR and VR and their integration with AI, robotic surgery, gaming, and wearables. CONCLUSIONS: AR and VR are promising technologies that will soon become part of standard of care in spine surgery. (C) 2021 Published by Elsevier Inc