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MAUSAM ◽  
2022 ◽  
Vol 73 (1) ◽  
pp. 79-82
Author(s):  
RAJESH KHAVSE ◽  
J.L. CHAUDHARY

Climate change is a natural phenomenon but in present decades its variability of change mainly due to anthropogenic activities is alarming. Agriculture of Chhattisgarh state is mainly dependant on monsoon rain and its distribution. Considering this fact, the present study  has been tried to analyze the most important climatic variables,              viz., precipitation and temeperature for analyzing their trend in the area. The trends of maximum atmospheric temperature, rainfall and rainy days are analysed statistically for meteorological data of Jagdalpur station of Bastar district, over last three decades stretching between years 1980 to 2014. The long term change in temperature, rainfall and rainy days has been analysed by correlation and linear trend analysis. The annual MMAX temperature has decreased at a rate of -0.465 °C per year during this period at Jagdalpur station and decreasing trend for rainy days during monsoonal season (June to September) is also found and is confirmed by Mann-Kendall trend test. Very weak increasing trend is observed in total month rainfall (TMRF) during season June to September. There are decreasing trends of mean monthly rainfall and south west (June - September) rainfall observed in Bastar district of Chhattisgarh. The agricultural planning and utilization of water is dependent on monsoon rainfall and more than 75% of rainfall occurring during the monsoon season is uneven both in time and space. Therefore its analysis is important for crop planning.  


MAUSAM ◽  
2022 ◽  
Vol 73 (1) ◽  
pp. 129-138
Author(s):  
Mostafa Abotaleb ◽  
Tatiana Makarovskikh ◽  
Aynur Yonar ◽  
Amr Badr ◽  
Pradeep Mishra ◽  
...  

Wind energy is one of the most important renewable energy sources in the world. Hence, the prediction of wind speed is a highly significant subject with respect to both protecting the environment and economic development. England is among the countries with an increasing interest in the potential for wind energy systems. In this study, various time series models, including BATS, TBATS, Holt’s Linear Trend, and ARIMA models were applied for wind speed prediction in England, and their performance was compared. The available wind speed data between 1994-07-07 and 2015-12-31 were divided into two parts: training data that is used to build up the models and testing data that is used to measure the validity of a model forecast. The results of the testing data indicate that the BATS and ARIMA outperform the other time series models according to the root mean square errors.


2022 ◽  
Author(s):  
Shijie Li ◽  
Guojie Wang ◽  
Chenxia Zhu ◽  
Jiao Lu ◽  
Waheed Ullah ◽  
...  

Abstract. Actual evapotranspiration (ET) is an essential variable in the hydrological process, linking the carbon, water, and energy cycles. Global ET has significantly changed in the warming climate. Although increasing vapour pressure deficit (VPD) due to global warming enhances atmospheric water demand, it remains unclear how the dynamics of ET are affected. In this study, using multiple datasets, we disentangled the relative contributions of precipitation, net radiation, air temperature (T1), VPD, and wind speed on affecting annual ET linear trend using an advanced separation method that considers the Budyko framework. It is found that the precipitation variability dominantly controls global ET in the dry climates, the net radiation has substantial control over ET in the tropical regions, and VPD is impacting ET trends in boreal mid-latitude climate. The critical role of VPD in controlling ET trends is particularly emphasized due to its influence in controlling the land-atmosphere interactions.


MAUSAM ◽  
2022 ◽  
Vol 52 (4) ◽  
pp. 717-726
Author(s):  
U. S. DE ◽  
G. S. PRAKASA RAO ◽  
A. K. JASWAL

Visibility plays a key role at the time of landing and take off operations at airports. The daily visibility data from 1969 onwards for 25 stations in the country (at 2100, 0000, 0300 and 0600 UTC) are examined for the winter period. Side by side the dry bulb temperatures and the relative humidity recorded at the same time are also examined. Linear trend regressions have been fitted on the data sets for each of the cities. The significance is tested at 99% level of confidence.   In recent years, degradation of air quality in the cities has often been suggested as the cause for the increase in the number of poor visibility days <2000 meters) particularly in the morning hours. Continuous persistence of this phenomenon for a number of days has also been reported.   The results show that there are decreasing trends in visibility at most of the stations. At 0300 UTC the visibility is generally low and increased afterwards due to mixing and turbulence in the boundary layer.


Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 463
Author(s):  
Piotr Bełdowski ◽  
Maciej Przybyłek ◽  
Alina Sionkowska ◽  
Piotr Cysewski ◽  
Magdalena Gadomska ◽  
...  

The ability to form strong intermolecular interactions by linear glucosamine polysaccharides with collagen is strictly related to their nonlinear dynamic behavior and hence bio-lubricating features. Type III collagen plays a crucial role in tissue regeneration, and its presence in the articular cartilage affects its bio-technical features. In this study, the molecular dynamics methodology was applied to evaluate the effect of deacetylation degree on the chitosan affinity to type III collagen. The computational procedure employed docking and geometry optimizations of different chitosan structures characterized by randomly distributed deacetylated groups. The eight different degrees of deacetylation from 12.5% to 100% were taken into account. We found an increasing linear trend (R2 = 0.97) between deacetylation degree and the collagen–chitosan interaction energy. This can be explained by replacing weak hydrophobic contacts with more stable hydrogen bonds involving amino groups in N-deacetylated chitosan moieties. In this study, the properties of chitosan were compared with hyaluronic acid, which is a natural component of synovial fluid and cartilage. As we found, when the degree of deacetylation of chitosan was greater than 0.4, it exhibited a higher affinity for collagen than in the case of hyaluronic acid.


2022 ◽  
Author(s):  
Sandy Herho ◽  
Gisma Firdaus

This pilot study presents a novel statistical time-series approach for analyzing daily rainfall data in Kupang, East Nusa Tenggara, Indonesia. By using the piecewise cubic hermite interpolation algorithm, we succeeded in filling in the null values in the daily rainfall time series. We then analyzed the monthly average and its pattern using the continuous wavelet transform (CWT) algorithm, which shows the strong annual pattern of rainfall in this region. In addition, we use the rainfall anomaly index (RAI) function to standardize daily rainfall as an indicator of dry/wet conditions in this region. Then we also use the daily RAI time-series objects from 1978 to 2020 for modeling and predicting daily RAI over the next year. The result is the root mean squared error (RMSE) of 0.8424041040593219. This Prophet model is also able to capture the linear trend of increasing drought throughout the study time period and the annual pattern of wet/dry conditions which is in accordance with previous study by Aldrian and Susanto (2003).


Author(s):  
Jigen Na ◽  
Huiting Chen ◽  
Hang An ◽  
Nan Li ◽  
Lailai Yan ◽  
...  

Background: Rare earth elements (REEs) are emerging contaminants. Previous studies reported the association between REEs and active smoking, but little is known about the effects of passive smoking on this condition. In China, female passive smoking is widespread, particularly in rural areas. Objective: This study aimed to estimate the relationship between REEs accumulation and passive smoking among rural housewives. Methods: We recruited 385 subjects in Shanxi Province of northern China, of whom 117 housewives were exposed to passive smoking, and 268 were not. We analyzed 15 REEs in the hair of housewives with ICP–MS, including lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, and yttrium. Results: The results indicated higher levels of 14 REEs except for Sm in both the univariate and adjusted models among the housewives exposed to passive smoking. The increasing linear trend of adjusted odds ratios of 15 REEs supported their association. The Bayesian kernel machine regression (BKMR) models showed that 15 REEs had a significant overall effect, and Eu had a single-exposure effect with passive smoking. Conclusion: We concluded that passive smoking might be associated with increased exposure to REEs among rural housewives.


2022 ◽  
Vol 6 (1) ◽  
pp. e001185
Author(s):  
Yefan Du ◽  
Ying Liao ◽  
Fangqun Leng ◽  
Linhua Li ◽  
Ruixue Ye ◽  
...  

BackgroundIron-deficiency anaemia disproportionately affects children in low-income and middle-income areas; Western China is a prime example. Given the health risks associated with childhood anaemia and the large heterogeneity of published studies on this subject, we conducted a systematic review of the evidence regarding anaemia prevalence and associated factors in children under 5 years in Western China.MethodsWe searched for all relevant studies on the prevalence of iron deficiency anaemia in children under 5 years in Western China, obtaining research between 1 January 2011 and 30 June 2021, in English and Chinese from Medline, Embase, PubMed, Web of Science, CNKI, WanFang Data and VIP. Two reviewers independently screened titles and abstracts; three reviewed full texts of relevant articles for data extraction and performed quality assessments. The median prevalence was calculated on unweighted pooling, stratified by region, sex, age and ethnic group. Associated factors and a linear trend chart were conducted to identify trends and research highlights.ResultsAmong the 55 articles included, most were cross-sectional studies (39, 70.91%). The prevalence of anaemia in children under 5 years in Western China ranged from 3.69% to 75.74% (median 42.54% (IQR 25.62%–52.56%)); the highest levels were in Qinghai province: 59.10%–75.74% (median 67.80% (IQR 64.70%–72.75%)); the highest levels were reported in the subgroup of children aged 6–12 months (median 50.09% (IQR 34.35%–59.04%)). Regional contexts, individual sociodemographic characteristics and feeding behaviours, and nutritional programme interventions were factors associated with anaemia prevalence.ConclusionThe prevalence of anaemia in children under 5 years in Western China is concerningly high. For this multiethnic and economically underdeveloped region, more high-quality and prospective studies are needed to inform evidence based and targeted preventive strategies to decrease the high prevalence of anaemia among young children.


2022 ◽  
Vol 60 (2) ◽  
Author(s):  
Vinícius Phillipe de Albuquerquemello ◽  
Rennan Kertlly de Medeiros ◽  
Diego Pitta de Jesus ◽  
Felipe Araujo de Oliveira

Abstract: Given the relevance of corn for food and fuel industries, analysts and scholars are constantly comparing the forecasting accuracy of econometric models. These exercises test not only for the use of new approaches and methods, but also for the addition of fundamental variables linked to the corn market. This paper compares the accuracy of different usual models in financial macro-econometric literature for the period between 1995 and 2017. The main contribution lies in the use of transition regime models, which accommodate structural breaks and perform better for corn price forecasting. The results point out that the best models as those which consider not only the corn market structure, or macroeconomic and financial fundamentals, but also the non-linear trend and transition regimes, such as threshold autoregressive models.


Author(s):  
Janis D. Harse ◽  
Kun Zhu ◽  
Romola S. Bucks ◽  
Michael Hunter ◽  
Ee Mun Lim ◽  
...  

Low vitamin D status has been linked to adverse cognitive outcomes in older adults. However, relationships at higher levels remain uncertain. We aimed to clarify patterns of association between vitamin D status and cognitive performance, using flexible regression methods, in 4872 middle- to older-aged adults (2678 females) from the Busselton Healthy Ageing Study. Cross-sectional associations of serum levels of 25-hydroxyvitamin D (25OHD) and performance in cognitive domains were modelled using linear regression and restricted cubic splines, controlling for demographic, lifestyle, and health factors. Mean ± SD serum 25OHD levels were 78 ± 24 nM/L for women and 85 ± 25 nM/L for men. Increasing levels in women were associated with better global cognition (linear trend, p = 0.023) and attention accuracy (continuity of attention), with improvement in the latter plateauing around levels of 80 nM/L (nonlinear trend, p = 0.035). In men, increasing levels of serum 25OHD were associated with better attention accuracy (linear trend, p = 0.022), but poorer semantic verbal fluency (linear trend, p = 0.025) and global cognition (nonlinear trend, p = 0.015). We identified patterns of association between serum 25OHD levels and cognitive performance that may reflect early dose–response relationships, particularly in women. Longitudinal analyses extending through to older ages may help to clarify the nature, strength, and temporality of these relationships.


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