Feasibility of a Fiber Reinforced Polymer Retrofit for Non-Ductile Concrete Walls

A significant number of pre-1980’s non-ductile reinforced concrete (RC) structures in California have been identified as deficient, many of which utilize RC shear wall systems to resist earthquake lateral forces. These non-ductile wall systems are typically lightly reinforced and lack adequate boundary element detailing. Engineers suspect these walls to susceptible to brittle, compression-controlled failure modes due to damage from concrete crushing and bar buckling. As a result, one approach designers are taking is to seek fiber reinforced polymer (FRP) retrofit solutions that improve the compression capacity of high-stressed wall end zone regions based on effectiveness of these approaches with columns. This paper presents the initial results from a lightly reinforced RC shear wall test without boundary elements intended to be representative of a vintage wall. The experimental test showed that the expected compression-type damage mechanisms were not the primary contributors of wall failure. Rather the failure was attributed to the development of few, large crack planes near the base of the wall and the fracture of most longitudinal bars at the wall-foundation interface. Additionally, the drift capacity was greater than anticipated. Therefore, the original proposed fiber reinforced polymer (FRP) retrofit developed by the authors in collaboration with industry input – wrapping the wall end zones with FRP sheets and thru-wall splay anchors to improve the compression capacity of these regions – may not be a viable approach. The research findings suggest that additional investigations into FRP solutions are necessary for different classes of non-ductile walls and their respective failure types

Evaluation of cortisol level in premature neonates: Are there any correlations between prevalence of patent ductus arteriosus and prenatal administration of betamethasone?

Background: The results of previous studies suggested that there is an increased risk of patent ductus arteriosus (PDA) in the neonates with lower serum cortisol levels. This study aimed to assess the association between serum cortisol values and PDA and investigate if there is an association between PDA and the antenatal administration of betamethasone. Methods: The present study was carried out on the neonates with gestational age between 28 to 35 weeks. The prenatal administration of betamethasone to the mothers was extracted from the records. A pediatric cardiologist performed an echocardiographic assessment on the second day of life (DOL) and fifth DOL and the infants were evaluated for the presence of PDA. The blood samples were obtained on the second and fifth DOL and serum cortisol levels were measured. We evaluated the association between serum cortisol levels and PDA. Also, the correlation between PDA and the antenatal administration of betamethasone was assessed. Results: The mean scores of serum cortisol levels on the second DOL in the neonates with and without PDA were 4.99±2.69 (μg/dl) and 7.23±2.87 (μg/dl), respectively that were significantly lower in the first group, compared to those of the second group. However, the mean levels of serum cortisol in the neonates with and without the prenatal administration of betamethasone were not significant (P=0.522). Conclusion: We have concluded that lower serum cortisol level was associated with the increase in the risk of PDA and the prenatal administration of glucocorticoids may not reduce the occurrence of PDA. © 2019 Mashhad University of Medical Sciences. All rights reserved

Passive noise control strategies for jets exhausting over flat surfaces : an LES study

Unconventional aircraft propulsion configurations have to be considered in the future to address environmental issues, including air traffic noise that is know to affect communities surrounding airports. One approach involves rectangular jets in the vicinity of flat surfaces that are parallel to the jet axis in an attempt to shield the noise, but previous experimental work indicated that there is an increase in the noise generated by these configurations, mainly associated with the effect that the plate trailing edge exerts on the flow. In this work, we use large eddy simulations to investigate the potential of wall deformations at the plate trailing edge to reduce jet noise. We consider a high aspect ratio rectangular nozzle exhausting a jet over a flat surface in different configurations, and estimate the farfield noise using the Ffowcs Williams and Hawkins acoustic analogy. Because of the high aspect ratio of the rectangular nozzle, we approximate the jet as being two-dimensional, and use periodic boundary conditions in the spanwise direction. For the configurations that we considered here, the trailing edge deformations did not seem to affect the noise significantly; an overall sound pressure level in the order of 1-2 dB was observed for some selected cases

Hydrodynamic resistance analysis of new hull design for multipurpose amphibious vehicle applying with finite volume method

This paper numerically investigated the hydrodynamic resistance of Multipurpose Amphibious Vehicles (MAV) in three bow shapes to approach the better hull bow shape design. This type of vehicle and other blunt-shaped floating vehicles encounter the problem of a large bow wave forming at high speeds. This wave formation is accompanied by higher resistance and at a critical speed results in bow submergence or swamping. Three new shapes of hull bow design for the multipurpose amphibious vehicle were conducted at several speeds to investigate the hydrodynamic phenomena using Computational Fluid Dynamics (CFD, RANS code) which is applied by Ansys-CFX14.0 and Maxsurf. The vehicle’s hydrodynamic bow shapes were able to break up induced waves and avoid swamping. Comparative results with the vehicle fitted with U-shape, V-shape and Flat-shape of hull bow, showed that the U-shape of the hull bow has reduced the total resistance to 20.3% and 13.6% compared with the V-shape and flat shape respectively. Though, the U-shape of hull bow is capable to increase the amphibious operating life and speed of vehicle in calm water. Also it has ability to reduce the vehicle’s required power, fossil fuel consumption and wetted hull surfac

The role of viral and bacterial infections in the pathogenesis of IPF: a systematic review and meta-analysis

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease. Several risk factors such as smoking, air pollution, inhaled toxins, high body mass index and infectious agents are involved in the pathogenesis of IPF. In the present study, this meta-analysis study investigates the prevalence of viral and bacterial infections in the IPF patients and any possible association between these infections with pathogenesis of IPF. Methods: The authors carried out this systematic literature review from different reliable databases such as PubMed, ISI Web of Science, Scopus and Google Scholar to December 2020.Keywords used were the following �Idiopathic pulmonary fibrosis�, �Infection�, �Bacterial Infection� and �Viral Infection�, alone or combined together with the Boolean operators "OR�, �AND� and �NOT� in the Title/Abstract/Keywords field. Pooled proportion and its 95 CI were used to assess the prevalence of viral and bacterial infections in the IPF patients. Results: In this systematic review and meta-analyses, 32 studies were selected based on the exclusion/inclusion criteria. Geographical distribution of included studies was: eight studies in American people, 8; in European people, 15 in Asians, and one in Africans. The pooled prevalence for viral and bacterial infections w ere 53.72 (95 CI 38.1�69.1) and 31.21 (95 CI 19.9�43.7), respectively. The highest and lowest prevalence of viral infections was HSV (77.7 95 CI 38.48�99.32), EBV (72.02, 95 CI 44.65�90.79) and Influenza A (7.3, 95 CI 2.66�42.45), respectively. Whereas the highest and lowest prevalence in bacterial infections were related to Streptococcus sp. (99.49, 95 CI 96.44�99.9) and Raoultella (1.2, 95 CI 0.2�3.08), respectively. Conclusions: The results of this review were confirmed that the presence of viral and bacterial infections are the risk factors in the pathogenesis of IPF. In further analyses, which have never been shown in the previous studies, we revealed the geographic variations in the association strengths and emphasized other methodological parameters (e.g., detection method). Also, our study supports the hypothesis that respiratory infection could play a key role in the pathogenesis of IP. © 2021, The Author(s)

Quantitative evaluation and identification of fungi in Shahid Rajaeii Dam Lake, Mazandaran Province (Sari)

The present study is carried out to investigate the fungal species present in water of Shahid Rajaeii damlake in Sari, (Mazandaran province). Samples were taken from five stations including, Station 1: Input of Shirinrud river, station 2: Input of Sefidrud river, Station 3: The confluence of the two branches, Station 4: dam crest and stations 5: Output dam from June to February 2012. Every sample was diluted by sterile saline (10-1 and 10-2) and 0.5 mL from each dilution was cultured on SD and incubated at 27-30°C for 3-5 days. Finally, the number of colonies wasrecorded as (colony forming unit = CFU) per 100 mL. Identification of fungal agents were conducted by slide culture preparation and stained in lacto-phenol blue. The results showed that in August and February were significantly highest and lowest rates of fungal colonies were isolated from water in different stations respectively. Moreover, the number of fungal colonies in the crown and the output was significantly higher than other stations. The frequency of identified fungi were: Aspergillus species (31.4%), various types of yeast (mainly Candida) (24.2%), Penicillium sp. (19.3%), Cladosporium sp.(10.3%), Mucor sp. (5.4%), Fusarium sp. (2.9%), sterile hype (2.8%), Alternaria sp. (2.3%) and Paecilomyces sp. (1.4%)

Survey and feasibility study for the introduction of native fish and non- native fish for cage culture in the southern part of Caspian Sea

The aim of this study is the feasibility of introducing suitable species of fish (native and exotic) for rearing in cages in the southern region of the Caspian Sea. This study from the perspective of economic efficiency and maintaining ecology were analyzed. The results showed that the southern Caspian Sea has the ability to aquaculture fish. However, due to the yearly temperature variations of water (from surface to a depth of 50 meters), the talent of aquaculture area is preferred for fish in cold water than warm water fish due to possibility rearing over the years. The survey showed that the current conditions and due to unfavorable changes in the ecology of the area in the last decade, the use of non-native fish culture in cages is not recommended. Many species of native fish are suitable for rearing in cages. Nevertheless, there is no infrastructure suitable for the production of all of them. Therefore, respectively species of Salmo caspius, Huso huso and Common carp of Caspian Sea for cultivation of in cages was suggested. In the current situation, this fish for their ability to grow faster than the need for selectivity. It is noteworthy that detailed environmental assessments and species risk assessments before the final introduction of any fish species (native and exotic) for rearing in cages in the Caspian Sea ecosystem is essential

A survey on health status of coldwater rearing and hatcheries fish farms in Iran (Mazandarn, Gilan, Ardebil, West Azerbaiejan, East Azerbaiejan and Kordestan provinces)

The national research plan with title of "Study on health status of Iran Coldwater hatchery and rearing farms" was done in order to identification and tracking of main causative agents of recent mortality in Iran Coldwater hatchery and rearing farms and recognize of infected zones and design of landscape distribution of Epizootic Coldwater fish diseases in the country. This plan was conducted parallel and in same time in some polar provinces of Coldwater fish production such as Mazandaran, Gilan, Ardebil, West Azerbaijan, East Azerbaijan and Kurdistan in three years from 2006-2008. In this regard, about 23,21 and 20 farms in Mazandaran province, 30 farms in West and East Azerbaijan and Kurdistan provinces and 19 farms in Gilan and Ardebil were selected as randomly and tracking were done yearly from 2006-2008. This research was conducted according to regular planning consists of farms visit that was done according to statistical plan and completion of Questionnaires and sampling. The findings in Mazandaran province revealed that fish infections background and infectious diseases were increased in period of 2006-2008. In fact, 56% of all fish farms in 2006, 71% in 2007 and 85% in 2008 were recorded as infected farms. In other side, average weight of fish final products was more 500gr in consume market. So, regarding to long period of fish culture in mentioned fish occurrence of more morbidity could be expected. The streptococcus infections were most important fish bacterial diseases that have more incidence and pathogenicity in collected questionnaires. Also it revealed more occurrences in summer season in above 15oC temperature in affected fish farms. Also, Enteric Redmouth Disease (ERM) and Saprolegniasis were reported as second and third degree in examined farms. Meanwhile, findings of control, prevention and treatment of our survey revealed that using of antibiotics and detergent materials were increased in mentioned province. Indeed, 34.7% of all fish farms in 2006, 71.4% in 2007 and 75% in 2008 have applied treatment operation and using of detergent materials in affected farms. In other side, frequent using of Erythromycin antibiotic was reported several times in 2008 so fish farmer faced to Bacterial resistance and should be using from Florfenicol as alternative antibacterial. Also, in feed sampling from all fish farms about 3 fish farms in 2006 and 5 fish farms in 2008 were faced with food poisoning that originated from high TVN and peroxidase in fish food consumed. These farms revealed mass mortality that stopped after change feeding regime. In conclusion absence of fish health management could be considered as main agent of mentioned mortality in Mazandaran province. The findings of our survey in West and East Azerbaijan and Kurdistan revealed that absence of sufficient experiences in fish farmers and their neglect from water quality concepts, farm cleanness, using of suitable detergent materials for fish ponds and instruments and disability in continuous monitoring of physic-chemical factors of consumed water could be considered as most important problems. So, fish morbidity and mortality, growth decrement and low production rate were expected. Unfortunately, despite the occurrence of infectious and non- infectious diseases in examined fish farms, there were no documents and information about diseases history, clinical signs in dead fish, feeding regime, fish mortality (rate of daily mortality, age and weight of moribund fish), treatment operation, drugs usage, growth rate, physico-chemical factors and fish density. So planning for control and prevention of mentioned diseases were unsuccessful in affected fish farms. Also, occurrence of some epizootic fish viral diseases such as VHS, IPN and IHN were observed frequently with mass mortality about 40100% in some examined fish farms that produced some tragic economic lost in the mentioned provinces. Similarly, some bacterial, fungal and parasitic diseases were observed repeatedly in some inspected farms such as Flavobacterium, streptococcus infections. Also, some unknown causative agents in parasitic diseases were observed several times such as Dactylogyrus, Gyrodactylus, Ichthyophthirius multifiliis, Trichodina, Chilodonella, Diplostomum and fungal diseases such as Saprolegniasis. In conclusion it seems that absence of fish health management, inadequate rate of hygienic technical services, absence of quarantine programs for transfer of new eyed-eggs, juvenile and live broodstocks packages without health certificates from authorized organizations, uncontrolled entry of foreign eyed-eggs (France, Denmark, Australia and Armenia) and neglect in using of suitable detergent materials for fish ponds, instruments, consumed water and infected eggs, not screening of broodstocks in hatcheries could be considered as most important causative agents in occurrence of infectious diseases and main problems in affected farms in mentioned provinces. Similarly, our findings in Gilan and Ardebil provinces revealed that their problems were similar to other provinces. In fact, neglect in establish of necessary Infrastructures in fish farms and dereliction in health management concepts could be considered as main reasons of occurrence of fish infectious and non-infectious diseases in studied fish farms in mentioned provinces. In fact, often fish farms visited hadn't suitable structures without control and prevention approach. There were not observed detergent using, quarantine programs and prevention methods. Entrance of unknown persons, birds and wild animals were ordinary in mentioned farms. Unfortunately level of farmer’s knowledge was low and no training courses and extension programs were planned by authorized organizations. Meanwhile, food storages were unsuitable and food packages were stored in inappropriate situation so poisoning conditions were increased in examined farms. In conclusion it could be finalized that Coldwater fish farms in Gilan and Ardebil provinces situated in insufficient position and correction of current situation are needed urgently. In final elicitation, it would be mentioned that lack of basic infrastructures could be introduced as most important reasonfor spread of diseases, mortality and related economic losses in studied provinces. Therefore, attention to environmental affairs and access to Sustainable Development are recommended. Also consideration of biosecurity regulations and health management concepts would be important requirements for modification and reformation of Coldwater fish farms in examined provinces towards A Better Tomorrow

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

Background: Many patients with COVID-19 have been treated with plasma containing anti-SARS-CoV-2 antibodies. We aimed to evaluate the safety and efficacy of convalescent plasma therapy in patients admitted to hospital with COVID-19. Methods: This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) is assessing several possible treatments in patients hospitalised with COVID-19 in the UK. The trial is underway at 177 NHS hospitals from across the UK. Eligible and consenting patients were randomly assigned (1:1) to receive either usual care alone (usual care group) or usual care plus high-titre convalescent plasma (convalescent plasma group). The primary outcome was 28-day mortality, analysed on an intention-to-treat basis. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Findings: Between May 28, 2020, and Jan 15, 2021, 11558 (71%) of 16287 patients enrolled in RECOVERY were eligible to receive convalescent plasma and were assigned to either the convalescent plasma group or the usual care group. There was no significant difference in 28-day mortality between the two groups: 1399 (24%) of 5795 patients in the convalescent plasma group and 1408 (24%) of 5763 patients in the usual care group died within 28 days (rate ratio 1·00, 95% CI 0·93–1·07; p=0·95). The 28-day mortality rate ratio was similar in all prespecified subgroups of patients, including in those patients without detectable SARS-CoV-2 antibodies at randomisation. Allocation to convalescent plasma had no significant effect on the proportion of patients discharged from hospital within 28 days (3832 [66%] patients in the convalescent plasma group vs 3822 [66%] patients in the usual care group; rate ratio 0·99, 95% CI 0·94–1·03; p=0·57). Among those not on invasive mechanical ventilation at randomisation, there was no significant difference in the proportion of patients meeting the composite endpoint of progression to invasive mechanical ventilation or death (1568 [29%] of 5493 patients in the convalescent plasma group vs 1568 [29%] of 5448 patients in the usual care group; rate ratio 0·99, 95% CI 0·93–1·05; p=0·79). Interpretation: In patients hospitalised with COVID-19, high-titre convalescent plasma did not improve survival or other prespecified clinical outcomes. Funding: UK Research and Innovation (Medical Research Council) and National Institute of Health Research