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We present a 14-year 12-km hourly air quality dataset created by assimilating satellite observations of aerosol optical depth (AOD) and carbon monoxide (CO) in an air quality model to fill gaps in the contiguous United States (CONUS) air quality monitoring network and help air quality managers understand long-term changes in county level air quality. Specifically, we assimilate the Moderate Resolution Imaging Spectroradiometer (MODIS) AOD and the Measurement of Pollution in the Troposphere (MOPITT) CO observations in the Community Multiscale Air Quality Model (CMAQ) every day from 01 Jan 2005 to 31 Dec 2018 to produce this dataset. The Weather Research and Forecasting (WRF) model simulated meteorological fields are used to drive CMAQ offline and to generate meteorology dependent anthropogenic emissions. Both the weather and air quality (surface fine particulate matter (PM2.5) and ozone) simulations are subjected to a comprehensive evaluation against multi-platform observations to establish the credibility of our dataset and characterize its uncertainties. We show that our dataset captures regional hourly, seasonal, and interannual variability in meteorology very well across the CONUS. The correlation coefficient between the observed and simulated surface ozone and PM2.5 concentrations for different Environmental Protection Agency (EPA) defined regions across CONUS are 0.77–0.91 and 0.49–0.79, respectively. The mean bias and root mean squared error for modeled ozone are 3.7–6.8 ppbv and 7–9 ppbv, respectively, while the corresponding values for PM2.5 are -0.9–5.6 µg/m3 and 3.0–8.3 µg/m3, respectively. We estimate that annual CONUS averaged maximum daily 8-hour average (MDA8) ozone and PM2.5 trends are -0.30 ppb/year and -0.24 μg/m3/year, respectively. Wintertime MDA8 ozone shows an increasing but statistically insignificant trend at several sites. We also found a decreasing trend in the 95th percentile of MDA8 ozone but an increasing trend in the 5th percentile. Most of the sites in the Pacific Northwest show an increasing but statistically insignificant trend during summer. An ArcGIS air quality dashboard has been developed to enable easy visualization and interpretation of county level air quality measures and trends by stakeholders, and a Python-based Streamlit application has been developed to allow the download of the air quality data in simplified text and graphic formats. [ABSTRACT FROM AUTHOR]

Asthma is the most frequent chronic airway illness in preschool children and is difficult to diagnose due to the disease's heterogeneity. This study aimed to investigate different machine learning models and suggested the most effective one to classify two forms of asthma in preschool children (predominantly allergic asthma and non-allergic asthma) using a minimum number of features. After pre-processing, 127 patients (70 with non-allergic asthma and 57 with predominantly allergic asthma) were chosen for final analysis from the Frankfurt dataset, which had asthma-related information on 205 patients. The Random Forest algorithm and Chi-square were used to select the key features from a total of 63 features. Six machine learning models: random forest, extreme gradient boosting, support vector machines, adaptive boosting, extra tree classifier, and logistic regression were then trained and tested using 10-fold stratified cross-validation. Among all features, age, weight, C-reactive protein, eosinophilic granulocytes, oxygen saturation, pre-medication inhaled corticosteroid + long-acting beta2-agonist (PM-ICS + LABA), PM-other (other pre-medication), H-Pulmicort/celestamine (Pulmicort/celestamine during hospitalization), and H-azithromycin (azithromycin during hospitalization) were found to be highly important. The support vector machine approach with a linear kernel was able to diffrentiate between predominantly allergic asthma and non-allergic asthma with higher accuracy (77.8%), precision (0.81), with a true positive rate of 0.73 and a true negative rate of 0.81, a F1 score of 0.81, and a ROC-AUC score of 0.79. Logistic regression was found to be the second-best classifier with an overall accuracy of 76.2%. Predominantly allergic and non-allergic asthma can be classified using machine learning approaches based on nine features. Supplemental data for this article is available online at at www.tandfonline.com/ijas. [ABSTRACT FROM AUTHOR]

Data from ozonesondes launched at ARIES Nainital (29.40o N, 79.50o E, and 1793 m elevation) are used to evaluate the Atmospheric Infrared Sounder (AIRS) version 6 ozone profiles and total column ozone during the period 2011-2017 over the central Himalaya. The AIRS ozone products are analyzed in terms of retrieval sensitivity, retrieval biases/errors, and ability to retrieve the natural variability of columnar ozone, which has not been done so far from the Himalayan region having complex topography. For a direct comparison, averaging kernels information is used to account for the sensitivity difference between the AIRS and ozonesonde data. We show that AIRS can provide quality data of ozone in the lower and middle troposphere and stratosphere with nominal underestimation (<20%). However, in the upper troposphere and lower stratosphere (UTLS), we observe a considerable overestimation of the magnitude as high as 102%. The weighted statistical error analysis of AIRS ozone shows higher positive bias, root mean squared error, and standard deviation in the upper troposphere of about 65%, 65%, and 25%, respectively. Similar to AIRS, Infrared Atmospheric Sounding Interferometer (IASI) and Cross-track Infrared Sounder (CrIS) are also able to produce ozone peaks and gradients successfully. However, the statistical errors are again higher in the UTLS region that are likely related to larger variability of ozone, lower ozone partial pressure and inadequate retrieval information on the surface parameters. The monthly variations of columnar ozone (total, UTLS, and tropospheric) are captured well by AIRS, except the total columnar ozone, which shows a strong bimodal variation, unlike unimodal variation seen in ozonesonde and Ozone Monitoring Instrument (OMI). Increases in ozone of 5 - 20% (in 2 - 6 km altitude) after the biomass burning and during events of downward transport (in 2 - 16 km altitude) are captured well by AIRS. Ozone radiative forcing (RF) derived from total column ozone matches well between ozonesonde (4.86 mW/m²) and OMI (4.04 mW/m²), while significant RF underestimation is seen in AIRS (2.96 mW/m²). The fragile and complex landscapes of the Himalayas are more sensitive to global climate change, and establishing such biases and error analysis of space-borne sensors will help study the long-term trends and estimate accurate radiative budgets. [ABSTRACT FROM AUTHOR]

Introduction: Hypospadias is a very common congenital anomaly noted in children with reported incidence of 0.4-8.2% in 1000 live birth. Treatment of hypospadias is urethroplasty, but is a difficult procedure due to complex anatomy, nonavailability of adequate tissue for repair, prolonged postoperative course and increased incidence of complications even in experienced hands. Aim: To highlight the complications and functional outcome of various types of proximal hypospadias using standard surgical technique with intermediate vascularised flap. Materials and Methods: This was a retrospective cohort study conducted from on 31 children, between the age of 2-13 years from June 2020 to August 2020. The children had proximal hypospadias with or without chordee were operated using primary procedure Tubularised Incised Plate (TIP) and staged procedure with cover of intermediate vascularised flap. These children had peno-scrotal, proximal, mid and distal penile hypospadias with meatus placed 1.5 cm proximal from the glans tip. In all cases, an intermediate layer of vascularised flap was put to cover the neourethra. Tunica vaginalis flap was used in 27 cases and dartos flap in 4 cases. The outcomes of surgical procedure, early and late complications with follow-up results were analysed using descriptive statistics of frequency and percentage. Final functional results of the procedures and cosmesis were observed during a two-year follow-up period. Results: Out of the 31 patients, 27 patients had urethroplasty (20 staged procedures and seven TIP) with tunica vaginalis as intermediate layer. Another four patients had TIP urethroplasty with dartos as intermediate layer. Four patients of tunica vaginalis as intermediate layer had early urethrocutaneous fistula (14.8%), one patient (3.7%) required closure of fistula and another three closed spontaneously. Two patients had meatal stenosis (7.4%) and four had slight pulled up ipsilateral testis (14.8%). One patient of TIP urethroplasty with dartos as intermediate layer was reoperated for late urethrocutaneos fistula at corona glandis (25%). Conclusion: The outcome of pediatric urethroplasty was favourable with routine use of intermediate vascularised flap in proximal hypospadias repair. [ABSTRACT FROM AUTHOR]

Introduction. Paresis of hand has severe impact on the life of the stroke patients. Modified constrained induced movement therapy (mCIMT) can be used to treat the involved limb of the patient. It involves constraining of functional hand and increasing the activity of paretic hand which overcomes the “learned disuse” that develops following stroke but the constraining also creates difficulties for the patient and reduces his/her compliance to the treatment. Hence this trial aims to study the effect of mCIMT with and without interval to see if providing relaxation in between the treatment would be able to produce similar effect as mCIMT without interval protocol. Matgerial and methods. 44 patients were recruited in the study and were divided in to three groups: mCIMT without interval (n = 18), mCIMT with interval (n = 16) and control group (n = 10). Participants in three groups were examined for pain and functionality of hand through Patient rated wrist hand evaluation score and Box and Block test at pre and post intervention. The intervention was given for 6 days/week for two weeks. Therapy time was 2 hours and constrain was for 6 hours a day. Clinical trial registration number -CTRI/2019/12/022547. Results. No baseline differences were found in between the three groups. There was significant increase in box and block test score and significant decrease in PRWHE score in pre and post treatment readings for with and without interval mCIMT but non-significant changes in PRWHE score and box and block test were seen in control group. Conclusion. Both interval and without interval mCIMT was effective. Interval mCIMT was seen to be more comfortable than without interval mCIMT for the patient. [ABSTRACT FROM AUTHOR]

Residents of the Kathmandu Valley experience severe particulate and gaseous air pollution throughout most of the year, even during much of the rainy season. The knowledge base for understanding the air pollution in the Kathmandu Valley was previously very limited, but is improving rapidly due to several field measurement studies conducted in the last few years. Thus far, most analyses of observations in the Kathmandu Valley have been limited to short periods of time at single locations. This study extends on the past studies by examining the spatial and temporal characteristics of two important gaseous air pollutant (CO and O3) based on simultaneous observations over a longer period at five locations within the valley and on its rim, including a supersite (at Bode in the valley center, 1345 m above sea level) and four satellite sites (at Paknajol, 1380 m asl in the Kathmandu city center, at Bhimdhunga (1522 m asl), a mountain pass on the valley's western rim, at Nagarkot (1901 m asl), another mountain pass on the eastern rim, and Naikhandi, near the valley's only river outlet). CO and O3 mixing ratios were monitored from January to July 2013, along with other gases and aerosol particles by instruments deployed at the Bode supersite during the international air pollution measurement campaign SusKat-ABC (Sustainable Atmosphere for the Kathmandu Valley - endorsed by the Atmospheric Brown Clouds program of UNEP). The O3 monitoring at Bode, Paknajol and Nagarkot as well as the CO monitoring at Bode were extended beyond July 2013 to investigate their variability over a complete annual cycle. Higher CO mixing ratios were found at Bode than at the outskirt sites (Bhimdhunga, Naikhandi and Nagarkot), and all sites except Nagarkot showed distinct diurnal cycles of CO mixing ratio with morning peaks and daytime lows. Seasonally, CO was higher during the pre-monsoon and winter seasons, especially due to the emissions from brick kiln industries, which only operate during this period, as well as increased domestic heating during winter, and regional forest fires and agro-residue burning. It was lower during the monsoon due to rainfall, which reduces open burning activities within the valley and in the surrounding regions, and thus reduces the sources of CO. The meteorology of the valley also played a key role in determining the CO mixing ratios. Furthermore, there was evidence of some influence of pollution from the greater region around the valley. A top-down estimate of the CO emission flux was made by using the CO mixing ratio and mixing layer height (MLH) measured at Bode. The estimated annual CO flux at Bode was 4.92 μg m-2 s-1, which is 2-14 times higher than that in widely used emission inventory databases (EDGAR HTAP, REAS and INTEX-B). This difference in CO flux between Bode and other emission databases likely arises from large uncertainties in both the top-down and bottom-up approaches to estimating the emission flux. The O3 mixing ratio was found to be highest during the pre-monsoon season at all sites, while the timing of the seasonal minimum varied across the sites. The daily maximum 8 hour average O3 exceeded the WHO recommended guideline of 50 ppb on more days at the hilltop station of Nagarkot (159/357 days) than at the urban valley bottom sites of Paknajol (132/354 days) and Bode (102/353 days), presumably due to the influence of free-tropospheric air at the high-altitude site, as well as to titration of O3 by fresh NOx emissions near the urban sites. More than 78% of the exceedance days were during the pre-monsoon period at all sites. This was due to both favorable meteorological conditions as well as contributions of precursors from regional sources such as forest fires and agro-residue burning. The high O3 mixing ratio observed during the pre-monsoon period is of a high concern for human health and ecosystems, including agroecosystems in the Kathmandu Valley and surrounding regions. [ABSTRACT FROM AUTHOR]

Air pollutants emitted from rapid urbanization and associated human activities in the Kathmandu Valley of Nepal over the past two decades are causing serious air quality and health concerns. These concerns led to a multinational field campaign SusKat-ABC (Sustainable atmosphere for the Kathmandu Valley-Atmospheric Brown Clouds) that measured different trace gases, aerosols and meteorological parameters in the Kathmandu Valley and surrounding regions during December 2012 to June 2013 to understand the factors influencing air quality of the Kathmandu Valley. This study provides information about the regional distribution of ozone and some precursor gases using simultaneous in situ measurements from a SusKat-ABC supersite at Bode, Nepal and two Indian sites: a high-altitude site Nainital located in the central Himalayan region and a low altitude site Pantnagar located in the Indo-Gangetic Plain (IGP). The diurnal variations at Bode showed a daytime buildup in O3 while CO shows morning and evening peaks. Similar variations (with lower levels) were also observed at Pantnagar but not at Nainital. Several events of hourly ozone levels exceeding 80 ppbv were also observed at Bode. The CO levels showed a decrease from their peak level of above 2000 ppbv in January to about 680 ppbv in June at Bode. The hourly mean ozone and CO levels showed a strong negative correlation during winter (r² = 0.82 in January and r² = 0.71 in February), but this negative correlation gradually becomes weaker, with the lowest value in May (r² = 0.12). The background O3 and CO mixing ratios at Bode were estimated to be about 14 ppbv and 325 ppbv respectively. The rate of change of ozone at Bode showed a more rapid increase (∼ 17 ppbv/hour) during morning than the decrease in the evening (5-6 ppbv/hour), suggesting a semi urban kind of environment at Bode. The slower evening time ozone decrease rates and lower CO levels during spring suggests an important contribution of regional transport than the contribution of local sources to the springtime ozone enhancement in the Kathmandu Valley. The winter time higher ozone levels at Bode are largely due to local sources with relatively less contributions from regional sources. We show that regional pollution resulting from agricultural crop residue burning in north-western IGP led to large (∼ 2-fold) increase in O3 and CO levels simultaneously at all three sites, i.e., Bode, Pantnagar and Nainital during first week of May 2013. Biomass burning induced increase in ozone and related gases was also confirmed by a global model and balloon borne observations over Nainital. A comparison of surface ozone variations and composition of light non-methane hydrocarbons among different sites indicated the differences in emission sources of the Kathmandu Valley and the IGP. These results highlight the contribution of regional sources to air pollution in the Kathmandu Valley versus the local sources in the Valley. [ABSTRACT FROM AUTHOR]