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Under the background of global warming, extreme weather events occur frequently, and cause serious harm to the economic development and people's lives in the Yellow River Basin and other regions. Therefore, it is necessary to explore its response to the atmospheric circulation and predict extreme temperature events in the Yellow River basin. Based on the daily temperature data of 80 stations in the Yellow River Basin from 1961 to 2020, the six monthly extreme temperature indexes(ETI)were calculated. Multi-collinearity analysis was used to remove the dependent circulation indexes, and the Pearson correlation analysis was conducted considering the lag. The key circulation indexes of each ETI were selected, and the optimal lag time of the circulation index to each ETI was determined according to the maximum value of Pearson correlation coefficient(r). Then, stepwise multiple linear regression(SMLR)and random forest(RF)models were established based on the selected key circulation indexes with specific lag time to evaluate the accuracy and explore the variable importance of circulation indexes at a single station and the whole basin. Six ETI of 80 stations in the Yellow River Basin in November 2022 were predicted. The results showed that: the TXx, TX90p, TD30 and TNn in the ETI of the Yellow River Basin showed a fluctuating upward trend, while the FD0 and TN10p showed a downward trend. Spatial distribution characteristics of extreme temperature warm indexes and cold indexes were basically opposite. Taking TXx of Jingyuan station as an example, each key circulation index had different degrees of influence on TXx(0.10 < rmax<0.89), and the lag time corresponding to rmax was mainly concentrated in 5, 6, 11 and 12 months. Both SMLR and RF models had good predictive ability for ETI in the Yellow River Basin, with R² of 0.53～0.95 and 0.64～0.95 in the validation period, respectively. Except for TXx, RF model had better simulation effect on the other five ETI than SMLR model. For the Yellow River Basin, the Pacific Polar Vortex Intensity Index(PPVI)was the most important predictor of TXx, TNn, TX90p and FD0, and the North African-North Atlantic-North American Subtropical High Ridge Position Index(NANRP)had the greatest influence on TN10p and TD30. The predicted extreme temperature indexes in November 2022 were basically similar to the multi-year average in spatial distribution. The results provide a reference for the prediction of extreme temperature events in the Yellow River Basin. [ABSTRACT FROM AUTHOR]

The temporal variability of air temperature in the Middle Volga region from 1828 to 2021 is considered according to instrumental observations at the oldest meteorological station in the east of the East European Plain (Kazan University) and throughout the Asian part of Russia against the background of long-term climate fluctuations in the Northern Hemisphere of Earth. A general trend toward an increase in air temperature was revealed. It was found that climate change in Kazan was consistent with the climatic processes that occurred in the Middle Volga region as a whole. The greatest warming for the entire observation period was observed in the winter and spring seasons of the year. In December, warming occurred at a maximum rate of 0.28 °C/10 years. At the same time, the most intense warming process was observed from 1991 to 2021. The analysis of low-frequency fluctuations in the series of monthly average air temperatures made it possible to identify different periods of change, both in type (direction) and intensity. It is shown that in the Middle Volga region, positive anomalies of air temperature have occurred more often than negative ones in recent decades. Statistical data processing was also carried out for 30-year periods, starting from the first period, i.e., 1841–1870. This made it possible to reveal long-term changes in air temperature. Comparisons of climatic parameters in two periods, i.e., 1828–1945 and 1946–2021, allowed us to reliably detect the climatic beginning of the increasingly identifiable Anthropocene epoch (since 1946), characterized by a sharp increase in air temperature, increased interannual variability of the air temperature regime, and a significant increase (by about three times) in the rate of warming in the Middle Volga region. A correlation was made between atmospheric circulation indices and air temperature fluctuations in Kazan over different periods. The closest relationship was found for the 1990–2020 period. It is shown that the contribution of global factors to air temperature variability in the Middle Volga region during the Anthropocene reached 37% in winter and 32% in summer; in annual terms, this contribution amounted to 54%. [ABSTRACT FROM AUTHOR]

The meteorological date from 26 meteorological station in the endorheic area in Alpine region were analyzed by means of liner regression method， 5-year moving average analysis method to get spatial and temporal variations of air temperature in the region， from 1969 to 2013.The result show that： （1） The endorheic area in Alpine region shows a warming trend from 1969 to 2017.Annual mean air temperature， mean maximum and mean minimum temperature had increased significantly， and the warming rate of minimum temperature is almost 1.5 times of that of maximum temperature.The spatial distribution of maximum temperature and minimum temperature increased from southeast to northwest.（2） The 12 extreme temperature indices showed statistically warming from 1961 to 2017.Warming indexes and GSL shows significant increasing while the some cooling indexes （TN10P、 TX10P）， ID， FD and DTR shows decreasing since mid-1960s.The spatial distribution of GSL， warm indices and some cold indices （TXN） increases in the north of the endorheic area in Alpine region， and the spatial distribution of FD and ID show significant increases in the south and southwest of the endorheic area in Alpine region.（3） The decrease of cooling indices was larger than the increase of warming indices， and the decrease of night indices was larger than the increase of day indices.（4） Extreme high temperature index （TXX， TXN） in the endorheic area in Alpine region is greatly affected by altitude， and the extreme temperature indices in the endorheic area in Alpine region has a warming trend， when the increased area， the high edge of regression and the increased intensity of the Atlantic subtropical high， or the increased intensity and the eastern position of the western Pacific subtropical high.

We discuss a case in which urinary L‐FABP measurements were used to manage a 46‐year‐old male patient receiving V‐A ECMO support. His mean blood pressure was ≥75 mmHg for the first 24 h after the initiation of V‐A ECMO, and he experienced a rapid decrease in urinary L‐FABP levels. [ABSTRACT FROM AUTHOR]

Typhoon is a devastating weather system, and the typhoon forecast is one of the most important issues to minimize their damages. In this study, we developed multiple linear regression, backpropagation neural network, support vector machine (SVM) and regression tree models and compared their results. To make a choice of reasonable predictors for statistical seasonal prediction of the number of typhoons, the climatology of typhoon activity over the Korean Peninsula and correlation between circulation indices in preceding winter and the number of typhoon approaching the Korean Peninsula (NTY-KP) were analyzed. The main findings were drawn as follows. (1) The interannual variability in NTY-KP for June–July–August–September during the period of 1949–2020 has a large variability, whose mean value is 2.51 and standard deviation is 1.55. (2) The lag correlation maps of NTY-KP with the area-averaged sea level pressure and geopotential height, air temperature, zonal and meridional wind anomalies at various isobaric levels in preceding winter over the area 10° S–90° N, 60° E–60° W were analyzed, and 22 indices described by difference between area-averaged climate variable anomalies over any two areas in preceding winter were chosen as potential predictors, and their own circulation linkages well related to NTY-KP were statistically identified. (3) In seasonal prediction experiments for NTY-KP, the prediction skills of several models were evaluated with correlation coefficient (R), root-mean-square-error (RMSE) and mean absolute error (MAE). The results show that SVM model had an obvious advantage over the other three models, with 0.9 of RMSE, 0.85 of R and 0.55 of MAE. [ABSTRACT FROM AUTHOR]

Abstract We discuss a case in which urinary L‐FABP measurements were used to manage a 46‐year‐old male patient receiving V‐A ECMO support. His mean blood pressure was ≥75 mmHg for the first 24 h after the initiation of V‐A ECMO, and he experienced a rapid decrease in urinary L‐FABP levels.

The temporal variability of air temperature in the Middle Volga region from 1828 to 2021 is considered according to instrumental observations at the oldest meteorological station in the east of the East European Plain (Kazan University) and throughout the Asian part of Russia against the background of long-term climate fluctuations in the Northern Hemisphere of Earth. A general trend toward an increase in air temperature was revealed. It was found that climate change in Kazan was consistent with the climatic processes that occurred in the Middle Volga region as a whole. The greatest warming for the entire observation period was observed in the winter and spring seasons of the year. In December, warming occurred at a maximum rate of 0.28 °C/10 years. At the same time, the most intense warming process was observed from 1991 to 2021. The analysis of low-frequency fluctuations in the series of monthly average air temperatures made it possible to identify different periods of change, both in type (direction) and intensity. It is shown that in the Middle Volga region, positive anomalies of air temperature have occurred more often than negative ones in recent decades. Statistical data processing was also carried out for 30-year periods, starting from the first period, i.e., 1841–1870. This made it possible to reveal long-term changes in air temperature. Comparisons of climatic parameters in two periods, i.e., 1828–1945 and 1946–2021, allowed us to reliably detect the climatic beginning of the increasingly identifiable Anthropocene epoch (since 1946), characterized by a sharp increase in air temperature, increased interannual variability of the air temperature regime, and a significant increase (by about three times) in the rate of warming in the Middle Volga region. A correlation was made between atmospheric circulation indices and air temperature fluctuations in Kazan over different periods. The closest relationship was found for the 1990–2020 period. It is shown that the contribution of global factors to air temperature variability in the Middle Volga region during the Anthropocene reached 37% in winter and 32% in summer; in annual terms, this contribution amounted to 54%.

Based on the daily data of 24 meteorological warfare points in Ningxia, the potential evaporation (ET0), the Mann–Kendall test (MK), and inverse distance weight interpolation were used to analyze the temporal and spatial changes in the potential evaporation at different scales, and the Pearson correlation coefficient was used to determine the growth rate in Ningxia. The atmospheric circulation influencing factors of seasonal potential evaporation were established, and the prediction model of potential evaporation in the growing season in Ningxia was established by stepwise linear regression, using mean absolute error (MAE), root mean square error (RMSE), and mean absolute percentage error (MAPE). The error test was carried out, and the results show the following: (1) The areas with larger potential evaporation during the growing season are mainly the central area of Ningxia and the northern side of the northern area. The presence on the north side tends to decrease. (2) On the monthly scale, the potential evaporation continued to increase from April to June, reached the maximum in June, continued to decrease from July to October, and was the smallest in October. (3) During the MK test in the growing season, the change in potential evaporation in the growing season showed an "increase–decrease" trend. The results of the monthly MK test show that the potential evaporation in April, May, and June has shown an increasing trend over the past 30 years, and the UF value in July, August, and October has been relatively high. The change trend of potential evaporation has been relatively stable, and the potential evaporation in September has shown a downward trend over the past 20 years. (4) The prediction model of potential evaporation in the growing season established by the circulation factor has shown a good effect in Ningxia and can be used to establish the scheduling prediction of irrigation water. [ABSTRACT FROM AUTHOR]

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Based on the daily data of 24 meteorological warfare points in Ningxia, the potential evaporation (ET0), the Mann–Kendall test (MK), and inverse distance weight interpolation were used to analyze the temporal and spatial changes in the potential evaporation at different scales, and the Pearson correlation coefficient was used to determine the growth rate in Ningxia. The atmospheric circulation influencing factors of seasonal potential evaporation were established, and the prediction model of potential evaporation in the growing season in Ningxia was established by stepwise linear regression, using mean absolute error (MAE), root mean square error (RMSE), and mean absolute percentage error (MAPE). The error test was carried out, and the results show the following: (1) The areas with larger potential evaporation during the growing season are mainly the central area of Ningxia and the northern side of the northern area. The presence on the north side tends to decrease. (2) On the monthly scale, the potential evaporation continued to increase from April to June, reached the maximum in June, continued to decrease from July to October, and was the smallest in October. (3) During the MK test in the growing season, the change in potential evaporation in the growing season showed an “increase–decrease” trend. The results of the monthly MK test show that the potential evaporation in April, May, and June has shown an increasing trend over the past 30 years, and the UF value in July, August, and October has been relatively high. The change trend of potential evaporation has been relatively stable, and the potential evaporation in September has shown a downward trend over the past 20 years. (4) The prediction model of potential evaporation in the growing season established by the circulation factor has shown a good effect in Ningxia and can be used to establish the scheduling prediction of irrigation water.

Chorioallantoic membrane (CAM) is an extraembryonic membrane very frequently used for in vivo studies in various researches. Since researches require a fast method for quantifying the CAM angiogenic response, there is a need to develop a new precise and unbiased method of quantification of angiogenesis in CAM, which would be easy to perform and suitable for analysis of a large number of samples. The objective of this paper is to apply a new method of quantification of angiogenesis in investigation of the development of blood vessels in the CAM, in particular days of embryonic life considered essential for CAM development. The present research included 75 fertilized eggs of heavy hybrid Ross 308. CAM sampling for stereological analyses was in key phases of embryonic development, namely on the 12th, 15th and 19th day. The results of the present investigation show that the increase in embryonic age results in increase in circulation index, which is also an indicator of angiogenic processes developing in CAM. The lowest value of circulation index (0.1952) was recorded on the first sampling day (E12), while the highest value (0.2666) was recorded on the last sampling day (E19). This method may be applied in researching different factors which affect angiogenesis in CAM.

Drought is a recurrent meteorological phenomenon that can be disastrous for humans; however, drought characteristics vary substantially in different regions. We use meteorological data from 140 stations in Northeast China for the period 1970-2014 to calculate the reconnaissance drought index (RDI) in order to examine droughts. We also analyze the strength of the relationships between the main large-scale atmospheric circulation patterns and RDI. Drought trends in the region are largely decreasing, but in the majority of cases, there is no statistical significance. Spatially, the pattern of droughts is a less frequent occurrence with greater severity and longer duration, mainly in the western part of the region. Severe droughts for the periods 1975-1979 and 2000-2004 were found, and most of these droughts occurred in the western part of Northeast China. The correlations between RDI and the atmospheric circulation indices POL, IAZC, and IEAT are negative, but the correlation between RDI and PDO is positive. The relationship between RDI and POL is stronger than the others, and the lagged effect is particularly obvious; thus POL can be recognized as the major driver of droughts over the period 1970-2014 in Northeast China. [ABSTRACT FROM AUTHOR]

The present study aims to (a) examine meteorological basis for construction of regional monsoon indices and (b) explore the commonality and differences among tropical regional monsoons, especially the teleconnection and monsoon-ENSO relationship. We show that the area-averaged summer precipitation intensity is generally a meaningful precipitation index for tropical monsoons because it represents very well both the amplitude of annual cycle and the leading mode of year-to-year rainfall variability with a nearly uniform spatial pattern. The regional monsoon circulation indices can be defined in a unified way (measuring monsoon trough vorticity) for seven tropical monsoon regions, viz.: Indian, Australian, western North Pacific, North and South American, and Northern and Southern African monsoons. The structures of the tropical monsoons are commonly characterized by a pair of upper-level double anticyclones residing in the subtropics of both hemispheres; notably the winter hemispheric anticyclone has a barotropic structure and is a passive response. Two types of upper-level teleconnection patterns are identified. One is a zonal wave train emanating from the double anticyclones downstream along the westerly jets in both hemispheres, including Indian, Northern African and Australian monsoons; the other is a meridional wave train emanating from the double anticyclones polewards, such as the South American and western North Pacific monsoons. Over the past 55 years all regional summer monsoons have non-stationary relationship with ENSO except the Australian monsoon. The regional monsoon-ENSO relationship is found to have common changing points in 1970s. The relationships were enhanced for the western North Pacific, Northern African, North American and South American summer monsoons, but weakened for the Indian summer monsoon (with a recovery in late 1990s). Regardless the large regional differences, the monsoon precipitations over land areas of all tropical monsoon regions are significantly correlated with the ENSO, suggesting that ENSO drives global tropical monsoon rainfall variability. These results provide useful guidance for monitoring sub-seasonal to seasonal variations of the regional monsoons currently done at NCEP and for assessment of the climate models' performances in representing regional and global monsoon variability. [ABSTRACT FROM AUTHOR]

Atmospheric variables play a fundamental role in driving man-managed ecosystems and more specifically in agro-ecosystems, determining the quantity and quality of crop production. On the other hand, climate variability can be seen as the superimposition of gradual and abrupt changes. This paper is focused on European surface air temperature in the period 1951-2010. Analysis of this dataset identified breakpoints that define two homogeneous sub-periods: 1951-1987 and 1988-2010. Thermal resources for crops were analyzed adopting a 'normal heat hours' approach. Computation highlighted a general increase in thermal resources in the European continent for crop groups II and III (C3 and C4 plants adapted to high or moderate temperatures), while a decline of thermal resources for crop group I (cold adapted C3) was highlighted in the Mediterranean area. The climate variability justifies a change in the potential latitudinal limits of different groups of crops, representing a fundamental step for crop adaptation to climate change. [ABSTRACT FROM AUTHOR]

The article discusses Australian monsoon index (AUSMI) multi-time scale. It states that the index is used to describe the seasonal cycle and measure the interannual, intraseasonal, and interdecadal variations of the Australian monsoon. It also mentions that the AUSMI is useful in examining the climate and weather variations of the Australian monsoon as well as validating the performance of climate models.

The shallow meridional overturning circulation (upper 1000 m) in the northern Indian Ocean and its interannual variability are studied, based on a global ocean circulation model (MOM2) with an integration of 10 years (1987–1996). It is shown that the shallow meridional overturning circulation has a prominent seasonal reversal characteristic. In winter, the flow is northward in the upper layer and returns southward at great depth. In summer, the deep northward inflow upwells north of the equator and returns southward in the Ekman layer. In the annual mean, the northward inflow returns through two branches: one is a southward flow in the Ekman layer, the other is a flow that sinks near 10°N and returns southward between 500 m and 1000 m. There is significant interannual variability in the shallow meridional overturning circulation, with a stronger (weaker) one in 1989 (1991) and with a period of about four years. The interannual variability of the shallow meridional overturning circulation is intimately related to that of the surface wind stress. Several indices are proposed to describe the anomaly of this circulation associated with the cross-equatorial part. [ABSTRACT FROM AUTHOR]