Spatio-temporal variations of PM2.5 and O3 in China during 2013-2021: Impact factor analysis.

Fine particulate matter (PM2.5) and ozone (O3) pollution are regarded as significant secondary air pollutants. The PM2.5 in most regions in China declined, and the decreasing rate in January was lower than the annual average. However, O3 concentration showed a steady increasing trend in most regions, and the increasing rate in July was slightly higher than the annual average. In particular, the annual average PM2.5 concentration and excess rate showed an increasing trend on the northern slope of the Tianshan Mountains. Conversely, O3 concentrations had shown a consistent increasing trend, exceeding the annual average limit of 100 µg/m3. Surface pressure exhibited positive correlations with PM2.5 in winter and O3 in summer across urban agglomerations. Moreover, soil temperature at different depths explained over 30% of the variations in PM2.5 and O3 in the Chengdu-Chongqing, Beijing-Tianjin-Hebei, and Lanzhou-Xining urban agglomerations. In winter, relative humidity demonstrated a positive correlation with urban agglomerations in northeast and northwest China, regions characterized by dry climates. During the COVID-19 period, the impacts of meteorological factors and soil temperature on PM2.5 and O3 differed significantly compared to preceding and subsequent periods. Notably, during the winter of 2020, the Harbin-Changchuan urban agglomeration exhibited a notable transition, as O3 and PM2.5 concentrations shifted from a strong negative correlation to a robust positive correlation. This remarkable shift, with deviations explained up to 60%, represents a unique phenomenon worth emphasizing in the study's findings.

Durable response of tislelizumab plus cisplatin, nab-paclitaxel followed by concurrent chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma: A case report.

RATIONALE: Limited patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC) have achieved complete response (CR) from induction chemotherapy (IC). Neoadjuvant immunotherapy combined with chemotherapy has marked therapeutic effects in some locoregionally advanced solid tumors. However, its efficacy and safety of NPC have not been reported so far. The rapid response of neoadjuvant tislelizumab combined with chemotherapy on LA-NPC may be associated with long-term survival benefit. PATIENT CONCERNS: A 57-year-old male patient presented with a 2-month history of bloody nasal discharge and right neck mass for 2 weeks. DIAGNOSIS: The patient was eventually diagnosed with nasopharyngeal nonkeratinizing undifferentiated cell carcinoma (stage IVA). INTERVENTIONS: The patient received tislelizumab combined with nanoparticle albumin-bound paclitaxel (nab-paclitaxel) nab-paclitaxel plus cisplatin for 4 cycles, followed by cisplatin-based concurrent chemoradiotherapy (CCRT). OUTCOMES: A partial response (PR) was achieved after 2 cycles of tislelizumab and nab-paclitaxel plus cisplatin, and CR was achieved after 4 cycles of neoadjuvant treatment. The duration of response lasted 24 months, and the patient was still in CR as of November 2022. The patient had no serious adverse event (AEs) during the treatment. LESSONS: This case report showed that tislelizumab combined with cisplatin plus nab-paclitaxel followed CCRT for treatment of patients with LA-NPC may receive a fast and durable response with a manageable safety profile and long-term survival.

[Spatio-temporal Variation Characteristics Monitored by Remotely Sensed Technique of PM2.5 Concentration and Its Influencing Factor Analysis in Sichuan Basin, China].

The spread of atmospheric pollutants in the Sichuan Basin is difficult because of its unique topography, static wind, high humidity, and other meteorological conditions. Owing to the acceleration of urbanization and industrialization, PM2.5 pollution in the region is becoming increasingly severe, and the Sichuan Basin has become one of the key areas of national air pollution prevention and control. In this study, based on the remote sensing inversion product of PM2.5 concentration, spatial autocorrelation and gray correlation analyses are used to evaluate the spatial and temporal distribution characteristics and influencing factors of PM2.5 concentration in the Sichuan Basin. The results show that PM2.5 concentration has significant spatial aggregation; the high-high aggregation types are concentrated, low-low aggregation types are more dispersed, and coniferous forest has a significantly higher inhibitory effect on the absorption of PM2.5 than the shrub, grassland, and other vegetation types. The main meteorological factors affecting PM2.5 concentration in the Sichuan Basin are wind speed and temperature; population density and economic scale are the main human-activity factors affecting PM2.5 concentration in the Sichuan Basin, and the change in the industrial structure and scale also has a certain influence on the PM2.5 concentration.

[Spatiotemporal variation and driving factors of growing season NDVI in the Tibetan Pla-teau, China.] / 青藏高原植被生长季NDVIæ—¶ç©ºå˜åŒ–ä¸Žå½±å“å› ç´ .

It is important to understand the response of vegetation to climate change in Tibetan Pla-teau (TP), an ecological barrier for China and Asia. The spatiotemporal variation of the normalized difference vegetation index (NDVI) of vegetation growing season were analyzed based on the gro-wing season NDVI retrieved from MOD09A1. The relationship between NDVI and climate factors was analyzed by combining the data of meteorological stations in TP from 2001 to 2018. The results showed that NDVI in the growing season showed a slow upward trend during the study period. There was substantial interannual variation of NDVI in different climate regions. The fluctuation magnitude of NDVI value was plateau humid climate region>semi-humid climate region>semi-arid climate region>arid climate region. The proportion of area with increasing and decreasing NDVI in humid climate region, semi-humid climate region, arid climate region, semi-arid climate region on TP were 1.4% and 1.9%, 4.9% and 1.5%, 16.4% and 0.8%, 7.0% and 2.0%, respectively. The areas of increasing NDVI in arid and semi-arid climate region was significantly larger than humid and semi-humid region. Temperature was the leading factor affecting the change of NDVI in humid and semi-humid region. The impact of precipitation on NDVI was significantly stronger than that of other climate factors in arid region. The impact of air temperature in growing season on NDVI was stronger than that of precipitation and relative humidity.

Vegetation dynamic analysis based on multisource remote sensing data in the east margin of the Qinghai-Tibet Plateau, China.

This study focuses on the vegetation dynamic caused by global environmental change in the eastern margin of the Qinghai-Tibet Plateau (EMQTP). The Qinghai-Tibet Plateau (QTP) is one of the most sensitive areas responding to global environmental change, particularly global climate change, and has been recognized as a hotspot for coupled studies on changes in global terrestrial ecosystems and global climates. An important component of terrestrial ecosystems, vegetation dynamic has become a key issue in global environmental change, and numerous case studies have been conducted on vegetation dynamic trends using multi-source data and multi-scale methods across different study periods. The EMQTP is regarded as a transitional area located between the QTP and the Sichuan basin, and has special geographical and climatic conditions. Although this area is ecologically fragile and sensitive to climate change, few studies about vegetation dynamics have been carried out in this area. Thus, in this study, we used long-term series datasets of GIMMS 3g NDVI and VGT/PROBA-V NDVI to analyze the vegetation dynamics and phenological changes from 1982 to 2018. Validation was performed based on Landsat NDVI and Vegetation Index & Phenology (VIP) data. The results reveal that the year 1998 was a vital turning point in the start of growing season (SGS) in vegetation ecosystems. Before this turning point, the SGS had an average slope of 9.2 days/decade, and after, the average slope was 3.9 days/decade. The length of growing season (LGS) was slightly prolonged between 1982 to 2015. Additionally, the largest national alpine wetland grassland experienced significant vegetation degradation; in autumn, the degraded area accounted for 63.4%. Vegetation degradation had also appeared in the arid valleys of the Yalong River and the Jinsha River. Through validation analysis, we found that the main causes of vegetation degradation are the natural degradation of wetland grassland and human activities, specifically agricultural development and residential area expansion.

Dynamic Changes of NDVI in the Growing Season of the Tibetan Plateau During the Past 17 Years and Its Response to Climate Change.

The fragile alpine vegetation in the Tibetan Plateau (TP) is very sensitive to environmental changes, making TP one of the hotspots for studying the response of vegetation to climate change. Existing studies lack detailed description of the response of vegetation to different climatic factors using the method of multiple nested time series analysis and the method of grey correlation analysis. In this paper, based on the Normalized Difference Vegetation Index (NDVI) of TP in the growing season calculated from the MOD09A1 data product of Moderate-resolution Imaging Spectroradiometer (MODIS), the method of multiple nested time series analysis is adopted to study the variation trends of NDVI in recent 17 years, and the lag time of NDVI to climate change is analyzed using the method of Grey Relational Analysis (GRA). Finally, the characteristics of temporal and spatial differences of NDVI to different climate factors are summarized. The results indicate that: (1) the spatial distribution of NDVI values in the growing season shows a trend of decreasing from east to west, and from north to south, with a change rate of -0.13/10° E and -0.30/10° N, respectively. (2) From 2001 to 2017, the NDVI in the TP shows a slight trend of increase, with a growth rate of 0.01/10a. (3) The lag time of NDVI to air temperature is not obvious, while the NDVI response lags behind cumulative precipitation by zero to one month, relative humidity by two months, and sunshine duration by three months. (4) The effects of different climatic factors on NDVI are significantly different with the increase of the study period.

Delayed Response of Lake Area Change to Climate Change in Siling Co Lake, Tibetan Plateau, from 2003 to 2013.

The Tibetan Plateau is a key area for research on global environmental changes. During the past 50 years, the climate in the Siling Co lake area has become continuously warmer and wetter, which may have further caused the increase in Siling Co lake area. Based on the Siling Co lake area (2003 to 2013) and climate data acquired from the Xainza and Baingoin meteorological stations (covering 1966 to 2013), we analyzed the delayed responses of lake area changes to climate changes through grey relational analysis. The following results were obtained: (1) The Siling Co lake area exhibited a rapid expansion trend from 2003 to 2013. The lake area increased to 2318 km², with a growth ratio of 14.6% and an annual growth rate of 26.84 km²·year(-1); (2) The rate of air temperature increase was different in the different seasons. The rate in the cold season was about 0.41 °C per ten years and 0.32 °C in hot season. Precipitation evidently increased, with a change rate of 17.70 mm per ten years in the hot season and a slight increase with a change rate of 2.36 mm per ten years in the cold season. Pan evaporation exhibited evidently decreasing trends in both the hot and cold seasons, with rates of -33.35 and -14.84 mm per ten years, respectively; (3) An evident delayed response of lake area change to climate change is observed, with a delay time of approximately one to two years.