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Dust is one of the major crises in the Middle East. In recent years, the frequency and intensity of this crisis in the region has increased and this has increased the need to study this phenomenon. In this article, we have studied the temporal and spatial changes of the dust storm phenomenon in Iran, Khuzestan (south-west) in the period 2000 to 2018. For this purpose, ground dust data and horizontal visibility and (Aerosol Optical Depth( data of MODIS satellite have been used. The AOD Optical Visibility Index has been declining from 2003 to 2007 and then increasing again. In general, we can see a gradual but increasing trend in the AOD index in the study area, from an average of 0.35 at the beginning of the period to nearly 0.6 at the end of the period, which indicates the predominance of dust storms in the region. The relationship between dust and climatic parameters was also examined. In terms of external storms, precipitation had a significant (P

BACKGROUND: Neonatal hypoxic-ischemic encephalopathy disproportionately affects low- and middle-income countries, where ≈96% of affected infants reside. The current standard of care, therapeutic hypothermia, is frequently ineffective in this setting, likely because injury may be occurring earlier during labor. Here, we studied the pharmacokinetics, safety, and efficacy of perinatal caffeine administration in near-term lambs following global ischemic injury to support the development of earlier treatment strategies targeting the fetus in utero as well as the infant postnatally. METHODS: Ewes were randomly assigned to receive either 1 g IV caffeine citrate or placebo before delivery and placental transport assessed. Near-term lambs (141-143 days) of both sexes were subjected to severe global hypoxia-ischemia utilizing an acute umbilical cord occlusion model. Lambs that received caffeine in utero also received 20 mg/kg IV caffeine citrate following resuscitation and 10 mg/(kg·d) IV for 2 days. An additional cohort received 60 mg/kg followed by 30 mg/(kg·d) (low dose versus high dose) postnatally. Biochemical, histological, and neurological outcome measures in lambs were assessed over a 6-day period. RESULTS: Perinatal caffeine administration demonstrated excellent placental transport kinetics and was well tolerated with lamb plasma levels comparable to those targeted in neonates with apnea of prematurity. Caffeine administration resulted in a systemic immunomodulatory effect, evidenced by significant reductions in proinflammatory IP-10 levels. Treated lambs demonstrated improved neurodevelopmental outcomes, while histological analysis revealed that caffeine reduced gray matter injury and attenuated inflammation in the cingulate and parasagittal cortex. This neuroprotective effect was greater and via a different mode of action than we previously reported for azithromycin. A higher caffeine dosing regimen demonstrated significant toxicity. CONCLUSIONS: Perinatal caffeine administration is well tolerated, attenuates systemic and brain inflammation, and contributes to improvements in histological and neurological outcomes in an ovine model of neonatal hypoxic-ischemic encephalopathy.

Drought as a natural hazard is a gradual phenomenon, slowly affecting an area; it may last for many years and can have devastating effects on the natural environment and in human lives. Although drought forecasting plays an important role in the planning and management of water resource systems, the random nature of contributing factors contributing to the occurrence of and severity of droughts causes some difficulties in determination of the time when a drought begins or ends. The present research was planned to evaluate the capability of linear stochastic models, known as multiplicative Seasonal Autoregressive Integrated Moving Average (SARIMA) model, in the quantitative forecasting of drought in Isfahan province based on the Standardized Precipitation Index (SPI). To this end, the best SARIMA models were chosen for modelling the monthly rainfall data from 1990 to 2017 for every 10 synoptic stations in Isfahan province to forecast their monthly rainfall up to five years. The monthly time scale SPI values based on these predictions were used to assess the drought severity of different stations for the 2018- 2022 time period. The station results indicated a weak drought at the 2019- 2022 period for Isfahan, Kashan and Naeen, a severe drought in 2019 for Ardestan and Golpaygan, and a weak one in 2019 for the East of Isfahan, KabootarAbad and Shahreza stations. All other stations, except Golpayegan, Isfahan, Kashan and Naeen, faced a severe drought in 2018.

OBJECTIVE: The objective is to examine the test-retest reliability and internal reliability of six self-report questions assessing both current (past 30 days) and lifetime cannabis smoking in an internet survey in the adult US population. DESIGN: Cross-sectional national survey. PARTICIPANTS: Out of 957 US adults who completed a national 2020 survey administered through Ipsos KnowledgePanel, 557 completed a second survey (reliability survey) aimed at assessing the test-retest and internal reliability of questions asking about current and lifetime cannabis smoking. The sample size used in the analysis for the six self-report questions varied and was dependent on respondents answering the questions in both the 2020 survey and the reliability survey. PRIMARY OUTCOME MEASURE: Test-retest and internal reliability of six self-report questions asking about current and lifetime cannabis smoking. RESULTS: Among respondents who had smoked cannabis in the past 30 days, 33.8% were aged 18-34, 29.7% were 35-49, 27.7% were 50-64 and 8.8% were 65 or older. Current cannabis smokers were primarily men (59.5%) and white (63.0%). Almost half of current cannabis smokers had a high school diploma or less followed by some college and a bachelors degree or higher (45.7%, 30.6%, 23.8%, respectively). The question assessing number of days participants smoked cannabis in the past 30 days demonstrated good test-retest (r=0.87) and excellent internal reliability (α=0.94). The questions assessing the number of years, the most common form of use and the number of times participants smoked cannabis over their lifetime also demonstrated test-retest (r=0.77 (acceptable), r=0.75 (acceptable) and κ=0.65 (substantial), respectively) and excellent-to-good internal reliability (α=0.91, α=0.87 and α=0.88, respectively). CONCLUSIONS: We found simple questions assessing current and lifetime cannabis use to demonstrate both test-retest reliability and internal reliability. These questions can serve as a simple framework for clinicians to evaluate the frequency of cannabis smoking in their patients. Future work should examine if these simple frequency measures of smoking cannabis are associated with adverse health outcomes.

Wind erosion is the most important geomorphic process and the main cause of the landscape change in arid and semi-arid areas. This paper focuses on the Dust Storm Index (DSI) with the aim of monitoring wind erosion in Central Iran using meteorology data. The trend of standardized DSI and its three factors which are sever dust storm, moderate dust storm and local dust events were studied using Man-Kendal non-parametric test. It was found that wind erosion is accelerating in recent years. Compared to primary 20 years (1965-1985) DSI rate has been three times more than 30 years ago (1985-2014). The central and southern parts of Central Iran show the highest severity of wind erosion and the severity of DSI decreases by approaching the north. Therefore, considering the sensitivity of these areas, in addition to taking into account prevention programs, they should also be considered in regeneration and control programs.

In this paper, hull/propeller interaction of a submarine model which has a realistic geometry, in submergence and surface conditions has been studied. For this purpose, the computational fluid dynamics (CFD) method has been used to solve the viscous, incompressible, two phase flow field (in surface condition) around a model of the propeller and submarine hull with and without propeller. The rotation of the propeller has been modeled using the sliding mesh technique. For turbulent flow modeling and free surface simulation, the k-ω SST model and the volume of fluid method (VOF) have been used, respectively. Experimental data obtained from test conducted by the authors in M.U.T. towing tank have been used to validate the numerical scheme. Comparing numerical and experimental results shows good agreement. The experimental and numerical results show that operation of the propeller near water surface reduces the thrust coefficient of the propeller comparing to open water condition, so that according to experimental results the maximum relative reduction of the thrust coefficient is 8.95%. In addition, the results indicated the amount of hull resistance coefficient in surface condition is more than submergence condition. According to the thrust reduction and wake factors obtained from the numerical results, it is known that their values in surface condition are less than submergence condition. This research can be used for more realistic investigation of hull/propeller interaction and thus, more accurate powering performance prediction of submarines.

BackgroundInfants with hypoxic-ischemic encephalopathy are often treated with therapeutic hypothermia and high-frequency ventilation. Fluctuations in PaCO2 during therapeutic hypothermia are associated with poor neurodevelopmental outcomes. Transcutaneous CO2 monitors offer a noninvasive estimate of PaCO2 represented by transcutaneously measured partial pressure of carbon dioxide (PtcCO2 ). We aimed to assess the precision between PtcCO2 and PaCO2 values in neonates undergoing therapeutic hypothermia.MethodsThis was a retrospective chart review of 10 neonates who underwent therapeutic hypothermia requiring respiratory support over 2 y. A range of 2-27 simultaneous PtcCO2 and PaCO2 pairs of measurements per neonate were analyzed via linear mixed models and a Bland-Altman plot for multiple observations per neonate.ResultsA linear mixed-effect model demonstrated that PtcCO2 and PaCO2 (controlling for sex) were similar. The 95% CI of the mean difference ranged from -2.3 to 5.7 mm Hg (P = .41). However, precision was poor as the PtcCO2 ranged from > 18 mm Hg to < 13 mm Hg than PaCO2 values for 95% of observations.ConclusionsThe neonates' PtcCO2 was as much as 18 mm Hg higher to 13 mm Hg lower than the PaCO2 95% of the time. Transcutaneous CO2 monitoring may not be a good trending tool, nor is it appropriate for estimating PaCO2 in patients undergoing therapeutic hypothermia.