Evento de blanqueamiento masivo en la zona norte del Gofo Pérsico, 2012

Coral bleaching events due to elevated temperatures are increasing in both frequency and magnitude worldwide. Mass bleaching was recorded at five sites in the northern Persian Gulf during August and September 2012. Based on available seawater temperature data from field, satellite and previous studies, we suggest that the coral bleaching threshold temperature in the northern Persian Gulf is between 33.5 and 34°C, which is about 1.5 to 2.5°C lower than that in the southern part. To assess the bleaching effects, coral genera counted during 60-minute dives were categorized into four groups including healthy, slightly bleached ( 50% bleached tissue) and fully bleached colonies. The anomalously high sea surface temperature resulted in massive coral bleaching (~84% coral colonies affected). Acropora spp. colonies, which are known as the most vulnerable corals to thermal stress, were less affected by the bleaching than massive corals, such as Porites, which are among the most thermo-tolerant corals. Turbid waters, suggested as coral refugia against global warming, did not protect corals in this study since most affected corals were found in the most turbid waters. The 2012 bleaching in the northern Persian Gulf was relatively strong from the viewpoint of coral bleaching severity. Long-term monitoring is needed to understand the actual consequences of the bleaching event on the coral reefs and communities.Los eventos de blanqueamiento de corales están aumentando en frecuencia y magnitud debido al aumento de la temperatura en los océanos. En este trabajo se describe un evento de blanqueamiento masivo observado en seis localidades del norte del Golfo Pérsico entre Agosto y Septiembre de 2012. Los datos de temperatura disponibles, medidas in situ y observaciones de satélites de la temperatura de la superficie del mar, sugieren que la temperatura umbral que desencadena el blanqueo de coral en el norte del Golfo Pérsico corresponde a una temperatura de entre 33,5-34°C que es una temperatura entre 1.5 a 2.5°C inferior a la observada en las zonas más meridionales del Golfo Persico (35-36°C). Para la evaluación de los efectos de blanqueo sobre las comunidades de coral, se realizaron transectos de 60 minutos entre 0 y 6 m de profundidad. Durante las inmersiones cada colonia de coral se identificó a nivel de género y su estado se asignó a una de las siguientes categorías: no afectada, ligeramente afectada ( 50% del tejido blanqueado) y colonias totalmente afectadas (100% del tejido blanqueado). El análisis de los datos de temperatura permitió identificar una anomalía térmica durante el periodo de blanqueamiento que afectó a un 84% de las colonias censadas. Contrariamente a otros eventos de blanqueamiento analizados, las colonias de Acropora spp., que se encuentran entre las especies más vulnerables al estrés térmico, fueron menos afectadas que las especies de corales masivos como Porites spp. que normalmente presentan una gran resistencia al estrés térmico. Igualmente a pesar que la turbidez de las aguas ha sido señalada como un factor protector en el contexto del calentamiento global, en nuestro estudio observamos que las zonas más afectadas por el blanqueamiento presentaban las tasas de turbidez más elevadas. En conclusión el evento de blanqueamiento de 2012 observado en el norte del Golfo Pérsico afectó severamente a las comunidades de coral. El seguimiento a largo plazo de las comunidades de coral se presenta como una necesidad para comprender las consecuencias de los eventos de blanqueamiento

Mass Mortality of Porites Corals on Northern Persian Gulf Reefs due to Sediment-Microbial Interactions

Little information is available on coral diseases in the Persian Gulf; however, in the recent years, reports of coral diseases increased in particular from Iranian side of the Persian Gulf. In this paper we report a White Mat Disease resulting in mass mortality of Porites colonies at Hormuz Island. This outbreak infected 96% of all Porites colonies and killed 58±30% (mean ± SD) of all Porites tissues

Nasal Carriage and Antibiotic Resistance Patterns of Staphylococcus aureus: A Case Study on the Nursing Students of Islamic Azad University of Eghlid Branch

Background and Aim: Staphylococcus aureus is an important cause of nosocomial infections. Many people are carriers for S. aureus in some parts of their body such as nose. In general, the population of carriers is higher among hospital staffs such as nurses who harbour antibiotic resistant staphylococcus strains which can be transmitted to patients. The aim of this study was to identify and evaluate the nasal carriage of S. aureus and determination of their antibiotic resistance patterns in a statistical population of nursing students in the Islamic Azad University of Eghlid Branch during 2014-2016. Materials and Methods: The relevant data were obtained using a questionnaire and the samples were then taken by rotating a moist cotton swab inside both nasal cavities of the nursing students. S. aureus strains were isolated and confirmed using conventional tests such as gram staining, catalase, coagulase and culture on DNase and Manitol salt agar. Antimicrobial susceptibility patterns against different antibiotics such as ampicillin, erythromycin, tetracycline, and chloramphenicol were carried out using Kirby-Bauer disk diffusion. Results and Conclusions: Out of the 216 students, 68 (%31.4) were nasal carriers of S. aureus. The results revealed that the highest and lowest antibiotic resistances rates were found against penicillin (%94.1) and ciprofloxacin (%3), respectively. A large number of students are nasal carriers of S. aureus which can increase the incidence of nosocomial infections. Therefore, it is recommended that screening and treatment for S. aureus be done for all the students and staff which are in direct contact with patients in hospitals

Detection of toluene degradation in bacteria isolated from oil contaminated soils

Toluene (C7H8) a hydrocarbon in crude oil, is a common contaminant in soil and groundwater. In this study, the ability to degrade toluene was investigated from twelve bacteria isolates which were isolated from soil contaminated with oil. Out of 12 bacterial isolates tested, most of Pseudomonas sp. showed the capability to grow in 1 mM of toluene compared with other isolates on the third day of incubation. Based on enzyme assays towards toluene monooxygenase, Pseudomonas aeruginosa UKMP-14T and Bacillus cereus UKMP-6G were shown to have the highest ability to degrade toluene. The toluene monoxygenase activity was analysed by using two calorimetric methods, Horseradish peroxidase (HRP) and indole-indigo. Both of the methods measured the production of catechol by the enzymatic reaction of toluene monooxygenase. In the HRP assay, the highest enzyme activity was 0.274 U/mL, exhibited by Pseudomonas aeruginosa UKMP-14T. However, for indole-indigo assay, Bacillus cereus UKMP-6G produced the highest enzyme activity of 0.291 U/ml. Results from both experiments showed that Pseudomonas aeruginosa UKMP-14T and Bacillus cereus UKMP-6G were able to degrade toluene

Microbiological Air Quality and Antibiotic Resistance in Isolated Bioaerosols from Various Activities in Zanjan, Iran

Introduction: The aim of this study is the isolation and primary identification of isolated bioaerosols sampled from different locations, as well as determining their antibiotic resistance profile for the selected bacteria. Materials and Methods: The air samples were collected from 35 stations in 17 buildings (bank, public, healthcare and industrial). An air-sampling pump (Flite3-SKC) with a flow rate of 14.1 l/min was used for five minutes at the respiratory height. The total bacterial count and primary identification were carried out, then the antibiotic susceptibility tests for ten selected antibiotics were conducted by the disk diffusion method.  Results: The bacterial population varied at a range of 128-5503 CFU/m3, and the fruit and vegetable bazaar of Zanjan showed the highest population of bioaerosols. The bioaerosols population among industrial samples was high. Most isolates were determined as gram-positive Cocci (> 70%) and Bacillus spp, respectively. The most antibiotic-resistant bacteria were related to manufacturing activities, showing resistance to Chloramphenicol and Trimethoprim/ Sulfamethoxazole (72%). Conclusion: The type of activity affects the bacterial population and antibiotic resistance in industrial uses. The increase of multi-drug resistant bacteria, especially in medical settings, is known as a community health challenge and needs more attention

Characterization and evaluation of catechol oxygenases by twelve bacteria, isolated from oil contaminated soils in Malaysia

Introduction: Catechol is a common intermediate compound in aromatic degradation process. Some microorganisms have this potentiality to degrade aromatic hydrocarbons by catechol dioxygenases to less toxic compounds with ability of entering the tricarboxylic acid cycle. In the present study, the catechol oxygenase activity was measured for 12 crude oil degrader bacteria. Materials and methods: Catechol oxygenase activity of two enzymes includes catechol 1, 2 dioxygenase and catechol 2, 3 dioxygenase were determined using spectrophotometer at 260 nm and 375 nm, respectively. Results: The highest enzyme activity for catechol 1, 2 dioxygenase by Bacillus cereus UKMP-6G was (0.07 U/mL) and about catechol 2, 3 dioxygenase was 0.031 U/mL by Rhodococcus ruber UKMP-5M during the first minute of incubation. Catechol 1, 2 dioxygenase and catechol 2, 3 dioxygenase followed the ortho and meta pathway, respectively. Discussion and conclusion: The enzyme assay results showed that among 12 examined bacteria, only R. ruber UKMP-5M has the ability to use meta pathway for degradation and produce 2-hydroxymuconic acid. The other isolates use ortho pathway and create cis, cis-muconic acid

The experiences of Red Crescent relief workers during the COVID-19 pandemic in Iran: a qualitative phenomenological study

Abstract Background The daily increase of infected individuals and mortalities related to COVID-19 in Iran increased public fear and anxiety and affected the job performance of many health workers, including the Iranian Red Crescent Society, as one of the organizations responding to COVID-19. Methods This study aimed to explore the experiences of Red Crescent rescuers, using a qualitative method with an interpretative phenomenological analysis (IPA), and by conducting semi-structured and in-depth interviews with Red Crescent relief workers from Mashhad in September 2020. Participants were selected by purposive sampling. Results Rescuers in the Red Crescent Society, had gained different experiences during the COVID-19 pandemic. The experiences were categorized into four main themes. These main themes were: (1) Psychological disorders, (2) Organizational support (3) Mis-management (both structural and human factors), and (4) Opportunities. Conclusion The COVID-19 epidemic did create unique opportunities to understand the pitfalls of the Red Crescent aid services. Red Crescent rescue workers suffered from psychological symptoms, and mismanagement was also present. Psychological support and organizational improvements should be implemented

Morphology, Microstructure and Physico-Mechanical Properties of Pasargad Bitumen, Modified by Ethylene-Vinyl Acetate Copolymer (EVA) and Nanoclay

Due to the characteristics such as flexibility, adhesion, hydrophobicity and low price, bitumen is used in different construction and insulation industries. The major problem with the bitumen material is its restricted physico-mechanical properties, mainly high temperature rutting and low temperature cracking. The aim of this work was to modify bitumen, produced in Tabriz Pasargad Oil Company, and evaluation of its different properties to make it suitable for the weather conditions of North West of Iran. The physico-mechanical, morphological and rheological characteristics of EVA/Cloisite 15A modified bitumen were studied.Two different feeding instructions were used in the mixing of bitumen with modifiers.In the first method, EVA and Cloisite 15A nanoclay were simultaneously added into the molten bitumen and in the second method, EVA and Cloisite 15A were premixed in an internal mixer before adding the polymer/nanoclay nanocomposite into the molten bitumen. The results showed that addition of nanoclay and polymer into the bitumen, led increased softening point and a decrease in the penetration of base bitumen, in which the extent of changes, was higher for the samples prepared by masterbatch method. The rheological properties of the pre-mixed samples exhibited more improvement and these samples showed more elastic behavior. The results of optical microscopy showed that the pre-mixing of polymer and nanoclay led to a more uniform distribution of the swollen polymer phase at the base bitumen. These samples also showed higher morphology stability than those samples prepared in single step. These effects were related to the probable localization of nanoclay at the interface of the two phases

Mass Mortality of Porites Corals on Northern Persian Gulf Reefs due to Sediment-Microbial Interactions

<div><div><p>Little information is available on coral diseases in the Persian Gulf; however, in the recent years, reports of coral diseases increased in particular from Iranian side of the Persian Gulf. In this paper we report a White Mat Disease resulting in mass mortality of Porites colonies at Hormuz Island. This outbreak infected 96% of all Porites colonies and killed 58±30% (mean ± SD) of all Porites tissues.</p><div><br></div></div></div