Significant Increasing Research Articles

Increasing trend in enterococcal bacteraemia and vancomycin resistance in a tertiary care hospital in Croatia, 2017–2021

Background The epidemiology of enterococcal bacteraemia has changed worldwide and vancomycin-resistant enterococci increasingly cause healthcare-associated infections) with limited treatment options. Studies show heterogeneity among countries, regions and individual hospitals. Methods We retrospectively analysed enterococcal bacteraemia with Enterococcus faecalis and E. faecium at the largest hospital in Croatia, University Hospital Centre Zagreb from January 2017 to December 2021. Results A total of 432 cases of enterococcal bacteraemia were identified with 256 (59.3%) due to E. faecalis and 176 (40.7%) to E. faecium. Enterococcal bacteraemia occurred more frequently in men (n = 270; 62.5%) and the median age of all patients was 62 years (IQR: 0–92). We found statistically significant increase in the incidence trend of bacteraemic episodes with an annual percent change of 20.9% (95% confidence interval 14.3 to 27.8; p = .002) predominantly due to an increase of E. faecalis bacteraemia. The majority of patients (362/432; 83.8%) had healthcare-associated infections and 38.0% (165/432) of patients were in the intensive care unit. The proportion of vancomycin-resistant enterococcal bacteraemia increased from 12.7% (n = 8/63) in 2017 to 25.7% (n = 29/113) in 2021, statistically significant increasing trend (p = .0455), mainly due to an increased proportion of vancomycin-resistant E. faecium (p = .0169). Conclusions This is the first study describing the trends in enterococcal bacteraemia and vancomycin-resistance in enterococci in Croatia. We found a rising trend in enterococcal bacteraemia and in the proportion of vancomycin resistance and identified the most vulnerable patient groups, notably intensive care unit patients.

Changes in Antimicrobial Resistance and Etiology of Blood Culture Isolates: Results of a Decade (2010-2019) of Surveillance in a Northern Region of Colombia.

BackgroundBloodstream infections (BSI) are important causes of morbidity and mortality worldwide. Antimicrobial surveillance is essential for identifying emerging resistance and generating empirical treatment guides, the purpose of this study is to analyze trends in antimicrobial susceptibility of BSI from 2010 to 2019 in healthcare institutions from Medellin and nearby towns in Colombia.MethodsA Whonet database was analyzed from the GERMEN antimicrobial surveillance network; frequency and antibiotic susceptibility trends were calculated on more frequent microorganisms using Mann Kendall and Sen’s Slope Estimator Test.Results61,299 isolates were included; the three microorganisms more frequent showed a significant increasing trend through time E. coli (Sen’s Slope estimator = 0.7 p = <0.01) S. aureus (Sen’s Slope estimator = 0.60 p = <0.01) and K. pneumonia (Sen’s Slope estimator = 0.30 p = <0.01). E. coli showed a significant increase trend in cefepime and ceftazidime resistance, while K. pneumoniae showed a significant increase in resistance to cefepime, ciprofloxacin, and gentamicin. P. aeruginosa increases its susceptibility to all analyzed antibiotics and S. aureus to oxacillin. No increasing trend was observed for carbapenem resistance.ConclusionAn upward trends was observed in more frequent microorganisms and resistance to third and fourth-generation cephalosporins for E. coli and K pneumoniae; in contrast, not increasing trends in antibiotic resistance was observed for P. aeruginosa and S. aureus. The essential role of AMR-surveillance programs is to point out and identify these trends, which should improve antibiotic resistance control.

ИССЛЕДОВАНИЕ ВОЗДЕЙСТВИЯ ИМПУЛЬСНОГО МАГНИТНОГО ПОЛЯ НА БИОЛОГИЧЕСКУЮ АКТИВНОСТЬ 1,1-БИС(1H-ИМИДАЗОЛ-1-ИЛ) МЕТАНИМИНА

The paper is devoted to the study of pulsed magnetic field impacting at the biological activity of a newly synthesized antifungal drug based on the imidazole 1,1-Bis(1H-imidazole-1-il)metanimine. Two experimental methods were consistently used for the study like as the treatment of an antifungal drug through installation of electromagnetic pulse emission and analysis of the results of treatment with the disco-diffusion method. During the experiments, the hypothesis of an increase in the antimycotic activity of an antifungal drug under the influence of a pulsed magnetic field was tested. The monitoring objects of the experiment were strains of the Penicillium adametzoides and the Aspergillus flavus. The antifungal drug was treated on the magnetic-pulse installation at the electromagnetic field strength H=(0.09÷0.27)∙106 A/m at frequency f=40 kHz with the number of pulses n=1. The analysis of experimental results has shown that the pulsed magnetic field has an effect on the antifungal drug, during which there is an inhibition of the growth of the colony of Aspergillus flavus by 71%. At the same time, in the process of studying the effect of the unirradiated antifungal drug impact at the grown colonies of the Aspergillus flavus, were not recorded the lysis zones increasing. Studying of the effect of the irradiated antifungal drug impact at the inhibition of the growth of the colony of the Penicillium adametzioides, there was not recorded lysis zones significant increasing. At the same time, during the experiment on the research of effect of the antifungal drug that was treated with a pulsed magnetic field at the grown colonies of the fungus Penicillium adametzioides, the maximum significant increase in lysis zones by 13% was discovered.

Trends in reconstructed monthly, seasonal and annual flows for Irish catchments (1900–2016)

Trends in reconstructed monthly, seasonal and annual flows for Irish catchments (1900–2016)

Projection of Future Extreme Precipitation in China Based on the CMIP6 from a Machine Learning Perspective

In recent years, China has suffered from frequent extreme precipitation events, and predicting their future trends has become an essential part of the current research on this issue. Because of the inevitable uncertainties associated with individual models for climate prediction, this study uses a machine learning approach to integrate and fit multiple models. The results show that the use of several evaluation metrics provides better results than the traditional ensemble median method. The correlation coefficients with the actual observations were found to improve from about 0.8 to 0.9, while the correlation coefficients of the precipitation amount (PRCPTOT), very heavy precipitation days (R20mm), and extreme precipitation intensity (SDII95) reached 0.95. Based on this, the precipitation simulations of moderate forced scenario for sharing socio-economic path (SSP2-4.5) from 27 coupled models in the Coupled Model Intercomparison Project Phase 6 (CMIP6) were used to explore potential changes in future extreme precipitation events in China and to calculate the distribution and trends of the PRCPTOT, extreme precipitation amount (R95pTOT), maximum consecutive 5-day precipitation (Rx5day), precipitation intensity (SDII), SDII95, and R20mm for the early 21st century (2023–2050), mid-21st century (2051–2075), and late 21st century (2076–2100), respectively. The results showed that the most significant increase in extreme precipitation indices is expected to occur by the end of the century, with the R95pTOT, Rx5day, and SDII95 increasing by 13.73%, 9.43%, and 9.34%, respectively, from the base period. The remaining three precipitation indexes, the PRCPTOT, SDII, and R20mm, also showed increases of 8.77%, 6.84%, and 4.02%, respectively. Additionally, there were apparent differences in the spatial variation of extreme precipitation. There were significant increasing trends of extreme precipitation indexes in central China and northeast China in the three periods, among which the total annual precipitation showed an increasing trend in central and northern China and a decreasing trend in western and south China. An increasing trend of annual precipitation intensity was found to be mainly concentrated in central China and south China, and the annual precipitation frequency showed a larger increasing trend at the beginning of this century. The annual precipitation frequency showed an increasing trend in the early part of this century. In general, all the indices showed an overall increasing trend in the future period, with the PRCPTOT, Rx5day, and SDII95 showing the most significant overall increasing trends.

Trends in prevalence and treatment rate of anemia in the U.S. population: cross-sectional study using data from NHANES 2005–2018

ABSTRACT Objectives To determine the trends in anemia prevalence, treatment rates, and their associated demographic and socioeconomic status factors in the U.S. nationally representative population. Methods We extracted data from individuals ≥20-year-old from the NHANES from 2005 to 2018. The trends of anemia prevalence and treatment were assessed by Cochran–Armitage test. The association between two dependent variables (anemia status and treatment) and demographic were examined by multiple logistic regression. Results The general anemia prevalence has a significant increasing trend from 5.71% to 6.86% (P trend<.001) from 2005 to 2018, whereas the trend in general anemia treatment rate was not significant (p = .148). Logistic regression showed that age groups (OR: 2.15for 60 or older vs. 20–39 years old), sex (0.47 for male vs. female), race (0.22 for NHW vs. NHB), education (0.80for some college or AA degree vs. less than high school), PIR (0.60 for ≥3.5 vs.≤1.3), and birthplace (0.88 for U.S. vs. other) were significantly associated with anemia. The factors significantly associated with anemia treatment were age group (1.51 for 60 years and older vs. 20–39 years old), sex (0.53 male vs. female), birthplace (1.88 U.S. vs. other), and insurance (1.80 for Yes vs. No). Conclusion While there was no significant increase in anemia treatment between 2005 and 2018, the anemia prevalence increased significantly, particularly among individuals with lower income, less education, and born outside the U.S. Moreover, the high anemia prevalence among NHB compared to other races indicated that more resources are needed to reduce disparities.

Separating anthropogenic and climate contributions to streamflow variations in Rietspruit sub-basin, South Africa

Human activities and climate change continue to alter streamflow in many river basins. In this study, the influence of human activities and climate variability on streamflow changes in the Rietspruit sub-basin (RSB), South Africa, were investigated using precipitation, potential evapotranspiration, and discharge data for the period 1986 to 2018. Trends in the hydrometeorological variables were assessed using the Mann-Kendall test while the change point in the annual streamflow data was identified using the Pettitt test and the double mass curve technique. Results revealed no statistically significant change in annual precipitation, whereas annual streamflow showed a significant increasing trend while potential evapotranspiration showed a decreasing trend. It was identified that the change point occurred around 1999, thereby dividing the streamflow data into the pre-change (1986–1999) period with comparatively low urban cover (8.3%), and the post-change period (2000–2018) with urban land covering 16.6% of the study area. The results demonstrate that from 1986 to 2018, the elasticity of streamflow with respect to precipitation and potential evapotranspiration was 0.26 and −2.01, respectively. This implies that streamflow in the study area is more sensitive to potential evapotranspiration than precipitation. Nonetheless, changes in land use/land cover, particularly the urban settlement which increased by 101% between 1986 and 2018, were more influential than climate variability for the significant increase in streamflow in the RSB. The results provide necessary information for water resource management, land use planning and ecosystem development in the near future. This study emphasizes the necessity of addressing nonlinear and dynamic hydrological processes as a result of human impact and climate associated changes.

Buprenorphine Use Trends Following Removal of Prior Authorization Policies for the Treatment of Opioid Use Disorder in 2 State Medicaid Programs

State Medicaid programs have implemented initiatives to expand treatment coverage for opioid use disorder (OUD); however, some Medicaid programs still require prior authorizations (PAs) for filling buprenorphine prescriptions. To evaluate the changes in buprenorphine use for OUD among Medicaid enrollees in states that completely removed buprenorphine PA requirements. This retrospective cross-sectional study analyzed the immediate and trend changes on buprenorphine use during 2013 to 2020 associated with removal of PA requirements using a controlled interrupted time series analysis to account for autocorrelation. Data were collected from Medicaid State Drug Utilization Data for 2 states (California and Illinois) that completely removed a buprenorphine PA during the study period, and buprenorphine prescriptions for OUD treatment were identified among Medicaid enrollees. Quarterly total number of buprenorphine prescriptions for each state was calculated, and stratification analyses were conducted by dosage form (films and tablets). Among the 2 state Medicaid programs (California and Illinois) that removed buprenorphine PAs, there was a total of 702 643 and 415 115 eligible buprenorphine prescription claims, respectively. After removing PA requirements for buprenorphine, there was an immediate increase that was not statistically significant (rate ratio [RR], 1.11; 95% CI, 0.76-1.61) in the number of all buprenorphine prescriptions in California and a statistically significant increase (RR, 6.99; 95% CI, 4.67-10.47) in the number of all buprenorphine prescriptions in Illinois relative to the change in the control states (Alabama, Florida, Idaho, Kansas, Mississippi, Nevada, South Dakota, and Wyoming). Additionally, there was a statistically significant decreasing trend in the number of all buprenorphine prescriptions in California (RR, 0.88; 95% CI, 0.82-0.94) and a statistically significant increasing trend in Illinois (RR, 1.11; 95% CI, 1.05-1.19) relative to the trend in control states. In this cross-sectional study, removal of buprenorphine PA requirements was associated with a statistically significant increase in the number of buprenorphine prescription fills among Medicaid populations in 1 of the 2 included states.

Abstract 5720: Niraparib enhances radiosensitivity of glioblastoma cells with proficient BRCA1/2 through proliferation-related nucleolar protein DDX21

Abstract Background Intrinsic resistance to irradiation is one of important factors leading to recurrence of glioblastoma (GBM) patients underwent standard treatment. The radiosensitization by various poly-(ADP-ribose)-polymerase (PARP) inhibitors have been intensively investigated in many solid tumor models especially harboring deficient BRCA1/2. However, the impact of a PARP1/2 inhibitor niraparib on radiosensitivity of glioblastoma cell lines with proficient BRCA1/2 and underling mechanisms has yet not been fully elucidated. Methods GDSC dataset with IC50 of PARP inhibitors and transcriptome profiles as well as NCI-60 cell lines with known survival fraction at 2 Gy (SF2) were used to deduce potential pathways by which PARP inhibitors suppress cell viability and confer radiosensitization through linear regression and reactome gene set enrichment analysis. Two GBM cell lines with proficient BRCA1/2, A172 and U-87-MG were used to evaluate IC50 and radiation dose enhancement factor DEF37 of niraparib by CCK8 experiment and clonogenicity assay. Changes in the distribution of cell cycle and DDX21 protein expression were analyzed with flow cytometry and western blot respectively. The involvement of DDX21 in the mechanism mediating radiosensization of niraparib was performed with small inference RNA experiment. Results Pathways relevant to ribosome biosynthesis and functions such as eukaryotic translation initiation, rRNA processing was found to be responsible for cytotoxicity of niraparib in 519 tumor cell lines. Moreover, mRNA expression of PARP1/2, genes participated in ribosome biosynthesis and homologous recombination (HR) were all significantly negatively associated with SF2 in 44 NCI-60 cell lines. The IC50 of niraparib in A172 and U-87-MG cell lines were 10.77±3.31 and 32.37±2.84 μM respectively. The DEF37 was established as 1.99 at 348 nM, 2.17 at 1044 nM for A172 cell line and 1.10 at 1056 nM, 1.44 at 3169 nM for U-87-MG cell line, respectively. Treatment with niraparib alone and in the combination with radiation (4 Gy) resulted in significant increase in fraction of G2 phase in both cell lines. Treatment with niraparib alone did not change protein expression level of DDX21 in both cell lines. However, knockdown of DDX21 with siRNA significantly reduced proliferation in U-87-MG cells. Niraparib at 1056 nM further decreased clonogenic number in the combination with 4 Gy radiation in U-87-MG cells compared with those treated with radiation alone. Importantly, knockdown of DDX21 resulted in significant increasing in clonogenic number of U-87-MG cells treated with radiation alone or the combination of niraparib and radiation compared with control cells. Conclusions Niraparib has radiosensitization effect for GBM cells with proficient BRCA1/2 at low concentration. DDX21 may be involved in the radiosensitization mechanism of niraparib. Citation Format: Jia Luo, He Xiao, Qian Chen, Yanlan Li, Chuan Chen, Mingying Geng. Niraparib enhances radiosensitivity of glioblastoma cells with proficient BRCA1/2 through proliferation-related nucleolar protein DDX21 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5720.

Spatiotemporal Evolution and Coupling Pattern Analysis of Urbanization and Ecological Environmental Quality of the Chinese Loess Plateau

Understanding the interactive coupling mechanism between urbanization and eco-environmental quality is crucial to achieve the goal of urban sustainable development. The Chinese Loess Plateau (CLP) was taken as the research object, and the city nighttime light index (CNLI) and remote sensing ecological index with local adaptability (LARSEI) were constructed based on the data from the Defense Meteorological Satellite Program’s Operational Linescan System (DMSP/OLS), National Polar-orbiting Partnership Visible Infrared Imaging Radiometer Suite (NPP/VIIRS), and Moderate Resolution Imaging Spectroradiometer (MODIS). Then, trend analysis, standard deviation ellipse (SDE), coupling degree (C), and coupling coordination degree (CCD) models were used to determine the spatiotemporal variation of urbanization and eco-environmental quality and its coupling relationship. The results show that: (1) the urbanization level of the CLP showed a trend of continuous improvement from 2000 to 2019. A significant increasing trend was found from the CNLI (slopeCNLI = 0.0030 yr−1, p &lt; 0.01), and its value rose from 0.07 in 2000 to 0.14 in 2019. In terms of spatial distribution, a multi-core distribution pattern with provincial capital cities as the core was presented in the CLP. The cities expanded at different degrees and presented a gradual concentrated expansion towards the southeast on the whole. (2) The eco-environmental quality in the CLP greatly increased during 2000 to 2019. An area with an increasing trend in the remote sensing ecological index with local adaptability (LARSEI) accounted for 58.82% and was mainly concentrated in the west and central part of the CLP. (3) The C and CCD between urbanization and eco-environmental quality in the CLP presented a trend of significant increase during 2000 to 2019 (slopeC = 0.0051 yr−1, p &lt; 0.01; slopeCCD = 0.0040 yr−1, p &lt; 0.01). The cities with a higher coupling degree were mainly located in the southeastern and northern parts of the CLP, while those with a higher coordination degree were scattered in the marginal parts of the CLP. The research results can provide suggestions for decision-making to achieve high-quality coordinated development of the cities in the CLP.

Implications of considering peri-implant bone loss a disease, a narrative review.

BackgroundPeri‐implantitis has been suggested to cause significant increasing proportions of implant failure with increasing time.PurposeTo assess whether implant failure rates in long term studies are matching the supposed high prevalence of peri‐implantitis.Material and MethodsThis paper is written as a narrative review of the long‐term clinical investigations available in the literature.ResultsSome implant systems have seen unacceptable marginal bone loss figures with time coupled to increased implant failure rates, resulting in the withdrawal of these systems. The reasons for such mishap are generally unknown, with the exception of one system failure that was found to be due to improper clinical handling. Modern, moderately rough implant systems have functioned excellently over 10–15 years of follow up with minor problems with marginal bone loss and implant failure rates within a few per cent. Machined implants have functioned adequately over 20–30 years of follow up. Implant failures occur predominantly during the first few years after implant placement. No significant increase of implant failures has been observed thereafter over 20–30 years of follow up.Over the years of our new millennium, scientific and technical advances have allowed the discovery of numerous molecular pathways and cellular interactions between the skeletal and immune system promoting the development of the interdisciplinary field called osteoimmunology. Nowadays, this knowledge has not only allowed the emergence of new etiologic paradigms for bone disease but also a new dynamic approach on the concept of osseointegration and MBL around oral implants, re‐evaluating our older disease oriented outlook. This facilitates at the same time the emergence of translational applications with immunological perspectives, scientific approaches based on omics sciences, and the beginning of an era of personalized dental implant therapy to improve the prognosis of oral implant treatment.ConclusionsOral implant systems have been found to function with very good clinical outcome over follow‐up times of 20–30 years. Registered implant failures have occurred predominantly during the first few years after implantation, and there has been no significant increase in late failures due to peri‐implantitis.

Effects of climate change, coal mining and grazing on vegetation dynamics in the mountain permafrost regions

The ecological environment in alpine regions is fragile and sensitive to land-use and land-cover (LULC) change and climate warming. However, there are limited studies on the response of LULC and vegetation activity to climate change and human interference in mountainous permafrost regions. Based on in-situ meteorological and multi-source remote sensing data, we performed time trend and partial correlation analyses to investigate the spatial and temporal variation of LULC, landscape pattern, and vegetation growth under the impact of climate change and human activities in the source region of the Datong River from 2000 to 2019. Our results showed that the alpine desert area decreased significantly at a rate of −13.1 km2 yr−1 (p < 0.05), while the alpine meadow area increased at a rate of 8.3 km2 yr−1 (p < 0.1). Mining and road areas showed a significant increasing trend at a rate of 3.2 km2 yr−1 and 1.2 km2 yr−1, respectively. The increasing alpine meadow and mining areas were mainly derived from alpine deserts and alpine wetlands, respectively. The number of alpine wetland patches increased significantly along with a significant decrease in the landscape shape index of the rivers. Vegetation growth, as indicated by the enhanced vegetation index (EVI) was positively correlated with temperature but negatively correlated with precipitation and solar radiation in 59.6%, 52.3%, and 56.5% of the vegetated areas, respectively (p < 0.05). Temperature was the dominant climate factor controlling vegetation dynamics, and the recent warming hiatus resulted in a significant increase in EVI for alpine deserts, but no significant changes in EVI for alpine wetlands and alpine meadows. Increasing risk of negative impacts from human activities, including mineral exploration and grazing, on vegetation distribution and growth was observed. This study provides clear evidence of the upward invasion of alpine meadows into alpine desert areas under warm and humid climatic conditions. As climate warming intensifies, alpine meadow expansion may be impeded by extreme precipitation and permafrost thawing.

Trends in suicide attempts and suicide deaths before and during the COVID-19 pandemic in New Taipei City, Taiwan: an interrupted time-series analysis.

The coronavirus disease 2019 (COVID-19) pandemic is an unprecedented global health crisis that may cause mental health problems and heighten suicide risk. We investigated the impact of the COVID-19 pandemic on trends in suicide attempts and suicide deaths in New Taipei City, Taiwan. The current study used the official daily data on suicide attempts and deaths in New Taipei City, Taiwan (4 million inhabitants) between 2015 and 2020 from the Taiwan National Suicide Prevention Reporting System. Interrupted time-series (ITS) analyses with parameters corrected by the estimated autocorrelations were applied on weekly aggregated data to examine whether the suicide trends during the early COVID-19 pandemic (late January to July 2020) deviated from previous trends (January 2015 to late January 2020). The impact due to the suicide prevention policy change was also examined (since August 2020). ITS analyses revealed no significant increases in both mean and trend on weekly suicide deaths during the COVID-19 pandemic and after the policy change. In contrast, there was a significant increasing trend in weekly suicide attempts since the COVID-19 outbreak at the rate of 1.54 attempts per week (95% confidence interval 0.49-2.60; p = 0.004). Sex difference analysis revealed that, however, this increasing trend was observed only in females not in males. The COVID-19 pandemic has different impacts on suicides attempts and deaths during the early pandemic in New Taipei City, Taiwan. The COVID-19 outbreak drastically increased the trend of suicide attempts. In contrast, the number of suicide deaths had remained constant in the investigated periods.

CHANGES IN BLOOD PARAMETERS OF GRASS CARP CTENOPHARYNGODON IDELLA (VALENCIENNES, 1844) FINGERLINGS UNDER THE EFFECT OF CHLOROFETE

The present study has carried out to clarify the changes of blood parameters of grass carp Ctenopharyngodon idella (Valenciennes, 1844), responding to chlorofete effect under laboratory conditions, in the presence and absence of aquatic plant Ceratophyllum demersum (L.). Three concentrations used during chronic exposure time extended to (15days). Blood tests of (R. B. Cs., Hb, P.C.V.) were studied for fish exposed to concentration investigated. The hematological parameters decreased with the increasing of pesticide concentrations. Moreover, values of indices (M.C.V.) showed significant increase with the increasing of pesticide concentration, particularly at highest concentration used (3.8) mg/l during (5, 6 and 9) days with absence aquatic plant. However, apparent increasing of (M.C.H.) were observed at especially at concentration of (3.8) mg/l during (6 and 9) days of exposure time. Significant increasing were recoded in (M.C.V.) values for treatment aquatic plant during (7 and 10) days at concentration (3.8) mg\l and during (10) days for (M.C.H.). The present study showed nonsignificant reduction in (M.C.H.C.) values for both treatments with and without aquatic plant.

Climate trend analysis for a semi-arid Borana zone in southern Ethiopia during 1981\u20132018

BackgroundUnderstanding the climate variability at local scale could help suggest local adaptation responses to manage climate associated risks. This paper analyzed the variability and trend of climate in semi-arid Borana zone of southern Ethiopia over the period 1981–2018 using Mann–Kendall (MK) test, Sen’s Slope Estimator (SEE) and inverse distance weighted (IDW) interpolation technique. Gridded (4 km * 4 km) climate data (daily precipitation, daily maximum temperature (Tmax) and minimum temperature (Tmin)) were collected from National Meteorology Agency (NMA) of Ethiopia.ResultsThe results revealed the study area received a mean monthly precipitation of 39.19 mm and a monthly mean Tmax and Tmin of 29.66 °C and 16.31 °C were observed respectively. Rainfall shows a significant increasing trend during August, October and November and extremely variable during December, January and February where CV > 100%. Tmax shows a significant warming trend during August but January, February, August and October exhibited similar trend for Tmin. Rainfall and Tmin shows a significant trend during Meher and no trend for the rest of the seasons. Mean annual rainfall shows a significant increase where no trend observed for both Tmax and Tmin at this timescale. Decadal rainfall and Tmin exhibited no trend but Tmax show significant warming trend during 2001–2010 decade. Better rainfall and cooler temperature were observed in the north central, northeastern and northwestern whereas the southeastern and southwestern regions were drier and warmer.ConclusionRainfall is highly variable than temperature both at temporal and spatial scales in Borana. The intensity of rainfall decreases from the northeastern and northwestern parts towards the southwest while temperature increased from the north central parts towards the southwest for Tmax and the southeast for Tmin. The effect of topography is substantial for the local scale variability observed in the study area. Internal variability is observed at temporal and spatial scales and therefore any adaptation responses to local climate variability should consider the microscale climate.

A regional (land–ocean) comparison of the seasonal to decadal variability of the Northern Hemisphere jet stream 1871–2011

Seasonal to decadal variations in Northern Hemisphere jet stream latitude and speed over land (Eurasia, North America) and oceanic (North Atlantic, North Pacific) regions are presented for the period 1871–2011 from the Twentieth Century Reanalysis dataset. Significant regional differences are seen on seasonal to decadal timescales. Seasonally, the jet latitude range is lower over the oceans compared to land, reduced from 20° over Eurasia to 10° over the North Atlantic where the ocean meridional heat transport is greatest. The mean jet latitude range is at a minimum in winter (DJF), particularly along the western boundary of the North Pacific and North Atlantic, where the land-sea contrast and SST gradients are strongest. The 141-year trends in jet latitude and speed show differences on a regional basis. The North Atlantic has significant increasing jet latitude trends in all seasons, up to 3° in winter. Eurasia has significant increasing trends in winter and summer, however, no increase is seen across the North Pacific or North America. Jet speed shows significant increases evident in winter (up to 4.7 ms−1), spring and autumn over the North Atlantic, Eurasia and North America however, over the North Pacific no increase is observed. Long term trends are generally overlaid by multidecadal variability, particularly evident in the North Pacific, where 20-year variability in jet latitude and jet speed are seen, associated with the Pacific Decadal Oscillation which explains 50% of the winter variance in jet latitude since 1940. The results highlight that northern hemisphere jet variability and trends differ on a regional basis (North Atlantic, North Pacific, Eurasia and North America) on seasonal to decadal timescales, suggesting that different mechanisms are influencing the jet latitude and speed. This is important from a climate modelling perspective and for climate predictions in the near and longer term.

Impact of Postoperative Radiotherapy on Overall Survival in Patients with pN1 Non-Small Cell Lung Cancer

Objective: to comparatively analyze overall survival (OS) in patients with non-small cell lung cancer (NSCLC) with affected lymph nodes (pN1) of the lung root after surgical and combination treatment with postoperative radiotherapy (PORT). Subjects and methods. OS was studied in 310 patients with grade 2-3 NSCLC. (pT1a-4N1M0): in 101 patients after lobectomy/bilobectomy, pulmonectomy with ipsilateral mediastinal lymphadenectomy and in 209 patients after combination treatment with the similar surgical volume and hypofractionated PORT (a single focal dose (SFD) of 3 Gy; 5 fractions per week, a cumulative focal dose (CFD) of 36-39 Gy (43.2-46.8 Gy-eq)) or classical fractionation (SFD2 Gy, 5 fractions per week, CFD44 Gy). An analysis was carried out in the groups of patients younger and older than 60 years with central or peripheral cancer, squamous cell carcinoma or adenocarcinoma, with different tumor grading according to the T criterion (T1-4). Results. PORT in radically operated patients with NSCLC increased 5- and 10-year OS rates only in central squamous cell lung cancer (56.1% and 39.5% vs.25.4% and 4.3%, p = 0.002). This group receiving combination therapy showed a statistically significant increasing trend in 5-year OS rates for both pT1-2 tumors (57.5% vs. 21.3%, respectively, p = 0.013) and pT3-4 tumors (53.9% versus 26.0%; p = 0.044), so did patients younger than 61 years (65.5% vs.29.4%, p = 0.008) and those over 60 years old (47.5% vs.21.3%, p = 0.047). Patients with peripheral squamous cell carcinoma or lung adenocarcinoma at any site exhibited no statistically significant increase in OS after PORT. In general, the 5- and 10-year OS rates in the compared groups were statistically significantly higher in the PORT group (47.9% and 28.9% vs. 27.1% and 11.4, p = 0.006). None of the analyzed subgroups showed a decrease in OS after PORT. Conclusion. In patients with pN1 NSCLC who had radical surgery via lobectomy/bilobectomy or pulmonectomy with ipsilateral mediastinal lymphadenectomy, PORT can be recommended only for those with central squamous cell carcinoma, regardless of tumor size and age group. In other subgroups of patients with pN1 NSCLC, PORT can only be performed within the scientific protocols. The expediency of PORT after bilateral mediastinal lymph node dissection needs to be investigated.

淮河流域蒸散发时空变化与归因分析

PDF HTML阅读 XML下载 导出引用 引用提醒 淮河流域蒸散发时空变化与归因分析 DOI: 10.5846/stxb202104181005 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 科技部重大研发计划（2018YFC1506606）；淮河流域气象开放研究基金（HRM201804） Spatiotemporal changes and attribution analysis of evapotranspiration in the Huai River Basin Author: Affiliation: Fund Project: Major R&D program of Ministry of Science and Technology,Huai River Basin Meteorological Open Research Fund 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:蒸散发（Evapotranspiration，ET）是联结土壤-植被-大气过程的纽带，对理解地表水热平衡至关重要。因此，量化分析ET时空变化特征、揭示其主要控制因子对区域用水管理和农业生产十分重要。利用遥感数据和气象数据，基于BEPS模型估算了1981-2019年的淮河流域ET，分析了该区域ET时空分布特征，并通过敏感度系数和贡献率方法对该区域的ET多年变化特征进行了归因分析，最后借助数值实验方法深入探究影响特湿润年（2003年）ET较低的主要原因。结果表明：（1）1981-2019年淮河流域多年平均ET为549.83 mm，其中夏季ET占全年ET的比值达到47.63%；1981年以来区域ET整体呈极显著上升趋势（4.41 mm/a，P<0.01）；季节上，除冬季外，其他三个季节的ET增幅均呈显著性增加（P<0.05），四季增幅速率大小依次为：夏季>春季>秋季>冬季；空间上，中东部和南部ET较高，重心模型显示ET高值区域呈显著的由北向南的移动趋势；（2）归因分析结果表明，淮河流域ET对气温变化最敏感，其次为相对湿度、太阳总辐射、叶面积指数（LAI）和降水，但ET对LAI的正敏感性逐渐增强导致LAI的显著升高对流域ET年际变化贡献最大（44.5%），其次是气温的升高（25.93%）；同时，LAI是春、夏、秋三季ET变化的主导因素，气温是冬季ET变化的主导因素；（3）数值实验显示高相对湿度是引起特湿润年（2003年）ET明显偏低的最主要因素，这与导致长时间序列ET变化的原因不同。因此，建议今后加强极端气候条件下ET变化的归因分析，为更有效地应对全球气候变化提供决策服务。研究结果能够为认识淮河流域环境变化对水循环影响及合理分配区域水资源提供科学参考。 Abstract:Evapotranspiration (ET) is a link between soil-vegetation-atmosphere interactions, which is an essential process in understanding both water and energy balances of an ecosystem. Accurate quantitative analysis of its spatiotemporal changes with revealing sound underline forcing factors are of importance to promote the agricultural production and water management of a region. Based on the modified BEPS model, we used the remote sensing data and meteorological data to simulate ET in the Huai River Basin from 1981 to 2019 and analyzed its temporal and spatial changes. We further performed the attributional analysis to quantify its influencing factors with the help of the sensitivity index and contribution rate means. At last, we explored the main reasons for the lower ET in the special humid year of 2003 by numerical experimental methods. Results showed the following:(1) the long-term average annual ET of the Basin was 549.83 mm from 1981 to 2019, with the largest proportion in summer (47.63%). The evolution of the ET was an extremely significant increasing trend (4.41 mm/a, P<0.01) since 1981. Seasonally, the increase rates of ET in the other three seasons except winter exhibited obvious increasing trends (P<0.05). The increase rates of ET in the four seasons, in descending order, was summer, spring, autumn, and winter. Across the Basin, high ET values were observed in the central, eastern and southern regions. The center of gravity model showed that the area with high ET values moved significantly from north to south on the spatial scale. Attribution analysis showed that air temperature appeared the most sensitive driver for ET, followed by relative humidity and total solar radiation, leaf area index (LAI) and precipitation. However, the positive sensitivity of ET to the LAI gradually increased so that the significant increase in LAI contributed most to the interannual variabilities of ET (44.5%) in the Basin, followed by the increase of air temperature (25.93%). Correspondingly, we also found that LAI was the leading factor in ET of the spring, summer and autumn, while air temperature was the most significant variable for the winter ET. Finally, our numerical experiments indicated that the high relative humidity was the most important factor responsible for the Basin's low ET in 2003- a year with high humid, which is different from the attribution of the long-term ET changes. It is suggested to strengthen the attribution analysis of ET under extreme climate conditions in the future, so as to provide decision-making service for coping with global climate change more effectively. The results could provide scientific guide for understanding environmental influence to water cycle and the rational allocation of regional water resources in the Huai River Basin. 参考文献 相似文献 引证文献

Carbon storage and understory plant diversity in boreal Larix gmelinii–Carex schmidtii forested wetlands: A comparison of harvest, fire and draining disturbance

Background: Forested wetlands are an important factor in carbon (C) sequestration. In this study, we compared the short-term effects (5 years) of three harvest intensities and two wildfire severities, and the mid-term effects (25 years) of four groundwater table depth (WTD) drainage for forestry on eco-system C storage and understory vegetation structures in Daxing’anling, northeast of China. Results: We found that: Low intensity harvest slightly enhanced ecosystem C storage, whereas moderate- and high-intensity harvest led to significant reductions (33.2-41.6%) in comparison with the control natural forested wetlands stand (274.54 t C·ha -1), and light and heavy burn caused the ecosystem C storage sig-nificant decreases by 27.8% and 45.2%. As for the drainage for forestry, the ecosystem C storage was higher at the low WTD (316.78 t C·ha -1), and diminished significantly by 24.1-28.1% with the increasing WTD on the forested wetland plantation transect. Compared with the control and high intensity harvest stands (8.28 t ha -1 yr -1, 5.08 t C·ha -1 yr -1 and 6.48 t ha -1 yr -1, 3.52 t C·ha -1 yr -1), significantly higher NPP (net primary productivity, defined by the biomass difference of two measurements) (69.1-83.2%) and annual C sequestration (52.0-78.7%) were observed in the low- and moderate-intensity harvest stands. Significant increases by 48.6% and decreases by 31.5% in NPP or by 52.9% in annual C sequestration were in light and heavy burn stands, respectively. In contrast, the NPP and annual C sequestration (3. 67-10. 34 t ha -1 yr -1 and 1. 59-4. 87 t C·ha -1 yr -1) showed a significant in-creasing trend with increasing WTD, respectively. The understory species diversity indices were generally lower in the harvest and burned stands than the control natural forested wetlands and more pioneer tree species regeneration occurred after the disturbances. Conclusion: Therefore, it seems that low intensity harvest and wildfire could sustain the ecosystem C sink and drainage for forestry is an effect way to restore C sequestration for this forested wetland type.

Long-term change in relative humidity across China from 1961-2018

Using observational data of daily relative humidity obtained from 2479 meteorological stations from 1961-2018 and the homogenized monthly data set of national ground meteorological stations, this paper analyzes the climate change characteristics of average relative humidity across China as well as in 9 individual regions. From 1961-2018, the climate change trend in annual average relative humidity across China was negligible, but there were large differences among different regions. Overall, annual relative humidity in the Qinghai-Tibet Plateau and Xinjiang area showed a significant increase, while Northwest China, Northeast China and northern North China showed a significant decrease. Seasonally, average relative humidity in China chiefly decreased in spring, and there was no discernable trend in other seasons. The Qinghai-Tibet Plateau showed a significantly increasing trend in winter, spring and summer, especially in spring; Xinjiang exhibited a significant increasing trend in winter, summer and autumn; Northeast China presented a significantly decreasing trend in winter; Northwest China, North China, Central China and East China witnessed a significantly decreasing trend in spring; and South China and Southwest China showed a slightly decreasing trend across all 4 seasons. Large urban agglomerations exert an influence on relative humidity to some degree, with urban areas experiencing lower relative humidity than rural areas.