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While heavy rainfall frequently takes place in southern China during summer monsoon seasons, quantitative precipitation forecast skills are relatively poor. Therefore, detailed knowledge about the raindrop size distribution (DSD) is useful in improving the quantitative precipitation estimation and forecast. Based on the data during 2018-2022 from 86 stations in a ground-based optical disdrometer measurement network, the characteristics of the DSD in Guangdong province are investigated in terms of the particle size distribution (N(D)), mass-weighted mean diameter (Dm) and other integral DSD parameters such as radar reflectivity (Z), rainfall rate (R) and liquid water content (LWC). In addition, the effects of geographical locations, weather systems (tropical cyclones, frontal systems and the summer monsoon) and precipitation types on DSD characteristics are also considered. The results are shown as follows. 1) Convective precipitation has a broader N(D) and larger mean particle diameter than the stratiform precipitation, and the DSD observations in Guangdong are consistent with the three-parameter gamma distribution. The relationships between the Z and R for stratiform and convective precipitation are also derived for the province, i.e., Z = 332.34 R1.32 and Z = 366.26 R1.42 which is distinctly different from that of the Next-generation Weather Radar (NEXRAD) Z-R relationship in United States. 2) In the rainy season (April-September), the Dm, R and LWC are larger than those in the dry season (October- March). Moreover the above parameters are larger, especially in mid-May, which is the onset of the South China Sea summer monsoon. 3) The spatial analysis of DSD shows that the coastal station observations indicate a smaller Dm and a larger normalized intercept parameter (log10Nw), suggestive of maritime-like rainfall. Dm is larger and log10Nw is smaller in the inland area, suggestive of continental-like rainfall. 4) Affected by such weather systems as the tropical cyclone, frontal system and summer monsoon, the DSD shows characteristics with distinct differences. Furthermore, frontal system rainfall tends to present a continental-like rainfall, tropical cyclone rainfall tends to have a maritime-like rainfall, and summer monsoon rainfall characteristic are between maritime- and continental-like cluster (raindrop concentration and diameter are higher than continental cluster and maritime cluster, respectively. [ABSTRACT FROM AUTHOR]

Summary: Anaerobic degradation has been demonstrated as an important pathway for the removal of sulfonamide (SA) in contaminated environments, and identifying the microorganisms responsible for the degradation of SA is a key step in developing bioaugmentation approaches. In this study, we investigated the anaerobic degradation activity of three SA [sulfadiazine (SDZ), sulfamethazine (SMZ) and sulfamethoxazole (SMX)] and the associated bacterial community in wetland sediments contaminated by aquaculture (in Fujian Province, coded with FJ), livestock farming (in Sichuan Province, coded with SC), or rural wastewaters (in Guangdong Province, coded with GD). Additionally, the combination of DNA‐stable isotope probing (SIP) with metagenomics was further applied to assess the active SA‐degrading microbes using SMX as a model SA. Among SDZ, SMZ and SMX, only SMX could be effectively dissipated, and the degradation of SMX was relatively fast in the microcosms of sediments with higher levels of SA contamination (FJ and SC). The anaerobic biotransformation pathway of SMX was initiated by hydrogenation with the cleavage of the N–O bond on the isoxazole ring. DNA‐SIP revealed that the in situ active anaerobic SMX‐degraders (5, 18 and 3 genera in sediments FJ, SC and GD respectively) were dominated by Proteobacteria in sediments FJ and SC, but by Firmicutes (two Family XVIII members) in sediment GD. Mycobacterium, unclassified Burkholderiaceae and Rhodocyclaceae were identified as the dominant active SMX‐degrading bacteria in both sediments FJ and SC. Higher proportions of antibiotic resistance gene and genes involved in various functional categories were observed in sediments FJ and SC. [ABSTRACT FROM AUTHOR]

Calonectria species are important plant pathogens on a wide range of hosts, causing significant losses to plant production worldwide. During our survey on phytopathogenic fungi from 2019 to 2021, diseased samples were collected from various hosts in Guangdong Province, China. In total, 16 Calonectria isolates were obtained from leaf spots, stem blights and root rots of species of Arachis, Cassia, Callistemon, Eucalyptus, Heliconia, Melaleuca and Strelitzia plants. Isolates were identified morphologically, and a multigene phylogenetic analysis of combined partial sequences of calmodulin (cmdA), translation elongation factor 1-alpha (tef1-α) and beta-tubulin (β-tubulin) was performed. These sixteen isolates were further identified as nine Calonectria species, with five new species: Ca. cassiae, Ca. guangdongensis, Ca. melaleucae, Ca. shaoguanensis and Ca. strelitziae, as well as four new records: Ca. aconidialis from Arachis hypogaea, Ca. auriculiformis from Eucalyptus sp., Ca. eucalypti from Callistemon rigidus, and Ca. hongkongensis from Eucalyptus gunnii. Moreover, we provide updated phylogenetic trees for four Calonectria species complexes viz. Ca. colhounii, Ca. cylindrospora, Ca. kyotensis and Ca. reteaudii. Our study is the first comprehensive study on Calonectria species associated with various hosts from subtropical regions in China. Results from the present study will be an addition to the biodiversity of microfungi in South China. [ABSTRACT FROM AUTHOR]

Aglaonema modestum (A. modestum) (Araceae) is an evergreen herbage, which is intensively grown as an ornamental plant in South China. A new disease was observed in A. modestum from 2020 to 2021 in Guangdong province, China. The disease symptoms associated with plants were initial leaf wilt, stem rot, and resulting plant death, leading to severe economic losses. In total, six Fusarium isolates were obtained from diseased plants. The putative pathogen was identified using both morphological characteristics and molecular phylogenetic analysis of calmodulin A (cmdA), RNA polymerase largest subunit 1 (rpb1), RNA polymerase II (rpb2), translation elongation factor-1α (tef1- α), and beta-tubulin (β -tubulin) sequences. Two Fusarium species were identified, namely, one new species, Fusarium aglaonematis (F. aglaonematis) belonging to Fusarium fujikuroi species complex. In addition, Fusarium elaeidis (F. elaeidis) belonging to the Fusarium oxysporum (F. oxysporum) species complex was also identified. Pathogenicity assays were conducted by inoculating each species into potted A. modestum plants and co-inoculating two species. The results showed that two Fusarium species could infect plants independently and can infect them together. Co-infection of these two species enhanced the disease severity of A. modestum. Compared to single inoculation of F. elaeidis , severity was higher and disease development was quicker when plants were only inoculated with F. aglaonematis. In addition, these two Fusarium species could infect Aglaonema plants without wounds, while inoculation with a physical injury increased disease severity. This is the first report of co-infection by F. aglaonematis and F. elaeidis causing stem rot on A. modestum worldwide. This study will be an addition to the knowledge of Fusarium diseases in ornamental plants. These results will provide a baseline to identify and control diseases associated with A. modestum. [ABSTRACT FROM AUTHOR]

Purpose: Little is known about the recent trends of hypertension in southern China. The aim of the study was to investigate the trends of hypertension in Guangdong Province between 2012 and 2019. Methods: We conducted two cross-sectional surveys in 2012 and 2019 in southern China, which included 10,970 and 27,483 participants, respectively, aged 35 to 75 years old using a method of stratified, multistage, and cluster sampling. Hypertension was defined as a mean systolic/diastolic blood pressure (SBP/DBP) ≥ 140/90mmHg, or a self-reported condition, or any pharmacological treatment in the last 2 weeks. In addition, according to the 2017 ACC/AHA guideline for high blood pressure, we estimated the prevalence and control rate of hypertension. Results: According to the 2010 Chinese guideline, the age-standardized rate of hypertension prevalence was 34.7% in 2012 and 36.9% in 2019 with a slight increase, while the prevalence of prehypertension was stable (14.5% vs 14.3%). Over the period of our study, 45.6% and 60.7% of hypertensive patients knew their diagnosis in 2012 and 2019, and 40.8% and 51.5% were using antihypertensive medications, respectively. The control rates increased from 15.1% to 23.6%. Hypertension prevalence was 64.5% in 2012 and 63.2% in 2019, and the control rate increased from 3.0% to 4.8% during the study period under the 2017 ACC/AHA guideline. Conclusion: Although the past 7 years have seen some progress in hypertension management, the rates of hypertension awareness, treatment, and control in southern Chinese remained regrettably low, and the prevalence rate was still high. [ABSTRACT FROM AUTHOR]

In this paper, a quantitative precipitation estimation based on the hydrometeor classification (HCA-QPE) algorithm was proposed for the first operational S band dual-polarization radar upgraded from the CINRAD/SA radar of China. The HCA-QPE algorithm, localized Colorado State University-Hydrometeor Identification of Rainfall (CSUHIDRO) algorithm, the Joint Polarization Experiment (JPOLE) algorithm, and the dynamic Z-R relationships based on variational correction QPE (DRVC-QPE) algorithm were evaluated with the rainfall events from March 1 to October 30, 2017 in Guangdong Province. The results indicated that even though the HCA-QPE algorithm did not use the observed rainfall data for correction, its estimation accuracy was better than that of the DRVC-QPE algorithm when the rainfall rate was greater than 5 mm h-1; and the stronger the rainfall intensity, the greater the QPE improvement. Besides, the HCA-QPE algorithm worked better than the localized CSU-HIDRO and JPOLE algorithms. This study preliminarily evaluated the improved accuracy of QPE by a dual-polarization radar system modified from CINRAD-SA radar. [ABSTRACT FROM AUTHOR]

Tibouchina seecandra is an evergreen shrub, a popular ornamental plant in China. From 2020 to 2021, a wilt disease was observed in T. seecandra in Guangdong province, China. The diseased plants showed typical wilt symptoms including drying out of lower leaves, plant dieback, and total death of the plant. When the diseased stems were sectioned, discolouration of vascular bundles was observed. At the commercial nurseries, the natural disease incidence reached almost 50%, leading to severe economic losses. The putative pathogen was isolated from symptomatic T. seecandra stems. Fusarium grosmichelii was identified as the causal agent by using morphology and molecular phylogeny of multi-loci (DNA-directed RNA polymerase II subunit, translation elongation factor1-alpha, and beta-tubulin) sequence data. Artificial inoculation assays were conducted on potted T. seecandra seedlings under controlled environmental conditions. The results showed that the fungus could produce wilt symptoms in T. seecandra which is similar to those observed in the field. The putative pathogen was re-isolated and Koch's postulates were fulfilled. This study provides the first report of F. grosmichelii causing T. seecandra wilt disease worldwide. Furthermore, these results will contribute to the knowledge of pathogenic Fusarium species on ornamental plants. • A new wilt disease was observed on Tibouchina seecandra commercial nurseries in China. • Fusarium grosmichelii was the pathogen based on morphology and phylogeny. • Fusarium grosmichelii causing this disease is the first report worldwide. • These results will provide a baseline to control diseases in Tibouchina seecandra. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a novel optimization model of dynamic voltage support planning. It considers the state transition course after great disturbance of large-scale receiving end networks (REN). The risk of contingency can be equivalent to the annual risk loss and it can be reduced by the appropriate dynamic voltage support. The annual risk loss consists of state separating risk costs and transferring risk costs. The objective function of dynamic voltage support planning is to maximize the yearly average profit of the state without and with additional dynamic voltage support for the power system. The model is able to describe all kinds of voltage instability scenarios caused by REN interior faults or interface failures properly. The optimal schemes of dynamic voltage support planning of Guangdong receiving end power grids in 2008 and 2010 are given as instance based upon the proposed model, which shows that the comprehensive allocation schemes are of great security and economical efficiency. [ABSTRACT FROM AUTHOR]

Alocasia longiloba is a popular ornamental plant in China, however pests and diseases associated with A. longiloba reduce the ornamental value of this plant. From 2016 to 2021, stem and root rot has been observed on A. longiloba in Guangdong Province, China. Once the disease became severe, plants wilted and died. A fungus was isolated from the diseased stem and identified as Fusarium elaeidis using both morphological characteristics and molecular analysis of DNA-directed RNA polymerase II subunit (rpb2), translation elongation factor-1α (tef1) gene and β-tubulin (tub2) sequence data. The pathogenicity test showed the fungus was able to produce typical symptoms on A. longiloba similar to those observed in the field. The original pathogen was reisolated from inoculated plants fulfilling Koch's postulates. This is the first report of Fusarium elaeidis causing stem rot on A. longiloba. These results will provide a baseline to identify and control diseases associated with A. longiloba. [ABSTRACT FROM AUTHOR]