Search

Background: Understanding factors associated with antiretroviral treatment (ART) adherence is crucial for ART success among people living with HIV (PLHIV) in the "test and treat" era. Multiple psychosocial factors tend to coexist and have a syndemic effect on ART adherence. We aimed to explore factors associated with ART adherence and the syndemic effect of multiple psychosocial factors on ART adherence among PLHIV newly starting ART in Guangdong Province, China. Methods: Newly diagnosed PLHIV from six cities in Guangdong Province were recruited between May 2018 and June 2019, and then followed up from May 2019 to August 2020. Baseline and follow-up data were collected from a questionnaire and the national HIV surveillance system, the follow-up data of which were analyzed in this study. A Center for Adherence Support Evaluation (CASE) index > 10 points was defined as optimal ART adherence, which was measured via participants' self-reported adherence during follow-up survey. Multivariable logistic regression was used to identify factors associated with ART adherence. Exploratory factor analysis (EFA) and multi-order latent variable structural equation modeling (SEM) were performed to explore the syndemic effect of multiple psychosocial factors on ART adherence. Results: A total of 734 (68.53%) follow-up participants were finally included in this study among the 1071 baseline participants, of whom 91.28% (670/734) had self-reported optimal ART adherence. Unemployment (aOR = 1.75, 95%CI: 1.01–3.02), no medication reminder (aOR = 2.28, 95%CI: 1.09–4.74), low medication self-efficacy (aOR = 2.28, 95%CI: 1.27–4.10), low social cohesion (aOR = 1.82, 95%CI: 1.03–3.19), no social participation (aOR = 5.65, 95%CI: 1.71–18.63), and ART side effects (aOR = 0.46, 95%CI: 0.26–0.81) were barriers to optimal ART adherence. The EFA and second-order latent variable SEM showed a linear relationship (standardized coefficient = 0.43, P < 0.001) between ART adherence and the latent psychosocial (syndemic) factor, which consisted of the three latent factors of medication beliefs and self-efficacy (standardized coefficient = 0.65, P < 0.001), supportive environment (standardized coefficient = 0.50, P < 0.001), and negative emotions (standardized coefficient=-0.38, P < 0.01). The latent factors of medication beliefs and self-efficacy, supportive environment, and negative emotions explained 42.3%, 25.3%, and 14.1% of the variance in the latent psychosocial factor, respectively. Conclusions: About nine out of ten PLHIV on ART in Guangdong Province self-reported optimal ART adherence. However, more efforts should be made to address barriers to optimal ART adherence. [ABSTRACT FROM AUTHOR]

Introduction: A high proportion of people living with HIV (PLHIV) present for care with advanced HIV disease (AHD), which is detrimental to "90‐90‐90" targets to end AIDS by 2030. This study aimed to explore the prevalence of and factors related to AHD among newly diagnosed PLHIV in Guangdong Province, China. Methods: Newly diagnosed PLHIV were recruited from six cities in Guangdong Province from May 2018 to June 2019. AHD was defined as an initial CD4 count <200 cells/µL or an AIDS‐defining event within one month of HIV diagnosis. Data from a questionnaire and the national HIV surveillance system were used to explore the potential factors related AHD. Results: A total of 400 of 997 newly diagnosed PLHIV were defined as having AHD with a proportion of 40.1%. After adjusting for statistically significant variables in univariate analysis, multivariable logistic regressions showed that individuals aged 30 to 39 years (adjusted odds ratio (aOR) = 1.77, 95% confidence interval (CI): 1.13 to 2.79) and ≥50 years (aOR = 1.98, 95% CI: 1.15 to 3.43) were at a higher risk of AHD than those aged 18 to 29 years. Participants diagnosed by voluntary counselling and testing (VCT) clinics were less likely to have AHD (aOR = 0.67, 95% CI: 0.48 to 0.94) than those diagnosed at medical facilities. Participants who had ever considered HIV testing (aOR = 0.66, 95% CI: 0.45 to 0.98) and who had high social support (aOR = 0.73, 95% CI: 0.55 to 0.97) were at a lower risk of AHD, whereas participants who had HIV‐related symptoms within one year before diagnosis were at a higher risk of AHD (aOR = 2.09, 95% CI: 1.58 to 2.77). The most frequent reason for active HIV testing was "feeling sick" (42.4%, 255/601), and the main reason for never considering HIV testing was "never thinking of getting HIV" (74.0%, 542/732). Conclusions: Low‐risk perception and a lack of awareness of HIV‐related symptoms resulted in a high proportion of AHD in Guangdong Province, especially among the elderly, those diagnosed at medical facilities and those with low social support. Strengthening AIDS education and training programmes to scale up HIV testing through provider‐initiated testing and counselling in medical facilities and VCT could facilitate early HIV diagnosis. [ABSTRACT FROM AUTHOR]

The width of cut tobacco strands is an important indicator for physical parameters as well as for the smoking quality. In some countries, cut width helps to distinguish fine-cut tobacco and pipe tobacco and thus differentiates taxation rate. A new method for rapid measurement of the width of cut tobacco strands was developed based on digital image processing, because the method described in ISO 20193, though easy to implement in factories, proved time consuming and generated high testing costs. The essence of this method is to determine the statistic width of incisions. The straight-line segments represent the width of strands of cut tobacco, from which the determination of the width for randomly placed tobacco strands could be achieved. Five kinds of samples ('ISO collaborative study samples 0.4 mm, 1.0 mm, 1.6 mm and 3.0 mm' and 'Guangdong baked 0.9 mm') were used to study the comparability of the measurement results between the method presented in this work and the current ISO method. Results show that accuracy and repeatability are comparable. In addition, the testing efficiency of the method presented in this work appears to be higher than the current ISO method, and it is thus a promising alternative method for measuring the width of strands of cut tobacco. [ABSTRACT FROM AUTHOR]

Flood is a very destructive natural disaster in the world that is strongly influenced by land-use change. Therefore, a comprehensive flood risk modeling considering the change in land-use is essential for understanding, predicting, and mitigating flood risk. However, most existing single modeling ignored the derivative effect of land-use change, which may reduce the reality of results. To further address the issue, this study presented an integrated model chain by coupling the Markov-FLUS model, the multiple linear regression and the improved TOPSIS model. By applying it in Guangdong Province, the future land-use simulation, spatialization of hazard-bearing bodies, and determination of flood risk were realized. The results show that the coupled model chain allows for good prediction of flood risk under different scenarios, which could be expressed by flood risk composite index (FRSI). In the natural growth scenario, the flood risk will show markedly increasing trend from 2020 to 2030 (FRSI = 2.06), with the high and highest risk zones will expand significantly. Spatially, these increased high flood risk zones mainly distributed on the periphery of existing built-up lands. On the contrary, the flood risk in ecological protection scenario tends to stabilize (FRSI = 1.98), which may be a reference for alternative development paths. These dynamic information identified by this model chain provides a deeper insight into the spatiotemporal characteristics of future high flood risk areas, which can facilitate reasonable flood mitigation measures to be developed at the most critical locations in the region. In further applications, more efficient spatialization models and climate factor are suggested to be introduced. • Presenting a model chain for flood risk prediction under land-use changes. • Model chain considers the derivative effect of land-use changes. • Model chain allows for a more realistic flood risk maps base on multi-scenarios. [ABSTRACT FROM AUTHOR]

• How to maintain and protect key ESs has become a crucial question. • Conservation priority areas in the GBA were identified. • Multi-scenario simulation of land use change by adopting the FLUS model. • Optimizing the urban scale system can effectively maintain the key ESs. • Coordinated development among cities will play a critical role in protecting key ESs. Effective land use management can better maintain ecosystem services, especially in urban agglomerations. However, rational urban scale systems and landscape patterns to maintain key ecosystem services (ESs) in highly urbanized areas remain poorly understood. Taking the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) as a study area, we quantified the spatio-temporal change of key ESs from 2000 to 2020 by the Integrated Valuation of Environmental Services and Tradeoffs (InVEST) model, and simulated land use change prior considering ES conservation priority areas under different multiple development scenarios in 2050 by adopting the future land use simulation (FLUS) model. The main findings were as follows: (1) From 2000 to 2020, natural habitat, water retention and carbon sequestration decreased by 5.5%, 7.9%, and 3.9%, respectively, while the soil conservation increased by 63.7%. (2) The proportion of different conservation priority areas ranged from 10.6% to 22.6%, which were mainly located in the mountainous region. (3) The urban land area would increase from 4286.00 km2 to 4802.25 km2 between 2020 and 2050 in the GBA, with a growth rate of 12.05%. Under the simulation scenarios, the new urban land was mainly distributed in megacities and supercities. (4) Under the integrative conservation scenario, the habitat quality index, water conservation, soil conservation and carbon sequestration would increase by 0.036, 7 × 104 t, 5.11 × 106 t and 0.93 × 106 t, respectively. To maintain the key ESs, we recommend optimizing the urban scale system, making it compact at the city scale and scattered at the regional scale, and strictly restricting the conversion of forestland and farmland adjacent to megacities into urban land. These findings were beneficial to achieve regional high-quality development and sustainable development via rational urban system and landscape management. [ABSTRACT FROM AUTHOR]

Multiple uncertainties from water resource allocation have posed new challenges to balanced regional development. On the one hand, in the context of global water shortage crisis, groundwater, as an important water supply module, is facing severe risk of shortage. On the other hand, the regional authorities need to coordinate the contradictory water demand brought by the heterogeneous water use objectives from multiple water use levels, and these demands are also subject to complex uncertainties. How to mitigate the risks posed by uncertainties, ensure regional water security and balance participants, is attracting the keen attention of decision-makers around the world. Therefore, this study establishes a decentralized bi-level multi-objective regional water resources allocation (RWRA) optimization model under hybrid uncertainty, aiming at an optimal quartet trade-off of equity, sustainability, equilibrium, and efficiency. To deal with the hybrid uncertainty in the model, water demand is set as a random fuzzy number, and the groundwater constraint is combined with fuzzy chance-constrained programming (FCCP). Then, the decentralized bi-level multi-objective model is solved by the bi-level interactive method based on the satisfactory solution incorporated with the chaotic-particle swarm optimization (CPSO) algorithm. The proposed model and solution approach are then applied to the Dongjiang River Basin in Guangdong Province of China to verify the validity and utility of the model. The results show that (1) the model can effectively meet the different objectives requirements of regional authority and sub-areas; (2) groundwater constraint parameters has a significant impact on the model results, especially the Gini coefficient decreases by 13.6% when groundwater is used as a water source supplement; (3) from single-level model to decentralized bi-level model, the satisfactory balance of the two levels increases from 0.1457 to 0.793, which indicates that the decentralized bi-level model makes the two levels more balanced than the single-level model. Based on the results, some management recommendations for participants are finally provided. • A decentralized bi-level multi-objective programming model for RWRA is established. • Quartet trade-off of equity, sustainability, equilibrium, efficiency is considered. • Groundwater constraint is combined with FCCP to reflect water supply uncertainty. • Random fuzzy variable is utilized to describe the uncertain water demand in RWRA. • A case study in the Dongjiang River of China is applied to verify the proposal. [ABSTRACT FROM AUTHOR]

Real-world evidence on inactivated COVID-19 vaccines against the SARS-CoV-2 B.1.617.2 (Delta) variant is limited. The authors of this cohort study analyzed vaccination, surveillance, screening, tracing, and quarantine data to determine the effectiveness of inactivated COVID-19 vaccines against infections, pneumonia, and severe or critical illness caused by the Delta variant. Visual Abstract. Effectiveness of Inactivated COVID-19 Vaccines Against the Delta Variant.: Real-world evidence on inactivated COVID-19 vaccines against the SARS-CoV-2 B.1.617.2 (Delta) variant is limited. The authors of this cohort study analyzed vaccination, surveillance, screening, tracing, and quarantine data to determine the effectiveness of inactivated COVID-19 vaccines against infections, pneumonia, and severe or critical illness caused by the Delta variant. Background: Real-world evidence on inactivated COVID-19 vaccines against the highly transmissible B.1.617.2 (Delta) variant of SARS-CoV-2 is limited, leaving an important gap in the evidence base about inactivated COVID-19 vaccines for use by immunization programs. Objective: To estimate inactivated vaccine effectiveness (VE) against the B.1.617.2 variant. Design: Retrospective cohort study. Setting: The study was based on the first outbreak of the B.1.617.2 variant in mainland China that was discovered and traced in Guangdong in May and June 2021. Participants: 10 805 adult case patients with laboratory-confirmed infection and close contacts. Measurements: Participants were categorized as unvaccinated, partially vaccinated (1 dose), and fully vaccinated (2 doses). We estimated VE against the primary outcome of pneumonia and the secondary outcomes of infections, symptomatic infections, and severe or critical illness associated with the B.1.617.2 variant. Results: Results are reported in the order of outcome severity. Of 10 805 participants, 1.3% contracted infections, 1.2% developed symptomatic infections, 1.1% had pneumonia, and 0.2% had severe or critical illness. The adjusted VEs of full vaccination were 51.8% (95% CI, 20.3% to 83.2%) against infection, 60.4% (CI, 31.8% to 88.9%) against symptomatic infection, and 78.4% (CI, 56.9% to 99.9%) against pneumonia. Also, full vaccination was 100% (CI, 98.4% to 100.0%) effective against severe or critical illness. By contrast, the adjusted VEs of partial vaccination against infection, symptomatic infection, and pneumonia were 10.7% (CI, −41.2% to 62.6%), 6.8% (CI, −47.4% to 61.0%), and 11.6% (CI, −42.6% to 65.8%), respectively. Limitation: Observational study with possible unmeasured confounders; insufficient data to do reliable subgroup analyses by age and vaccine brand. Conclusion: Full vaccination with inactivated vaccines is effective against the B.1.617.2 variant. Effort should be made to ensure full vaccination of target populations. Primary Funding Source: National Natural Science Foundation of China and Key-Area Research and Development Program of Guangdong Province. [ABSTRACT FROM AUTHOR]

A solid phylogenetic framework is the basis of biological studies, yet higher level relationships are still unresolved in some major vertebrate lineages. One such group is Crocodylia, where the branching pattern of three major families (Alligatoridae, Crocodylidae and Gavialidae) has been disputed over decades due to the uncertain relationship of two slender-snouted lineages, gavialines and tomistomines. Here, we report a bizarre crocodylian from the Bronze Age of China, which shows a mosaic of gavialine and tomistomine features across the skeleton, rendering support to their sister taxon relationship as molecular works have consistently postulated. Gavialine characters of the new Chinese crocodylian include a novel configuration of the pterygoid bulla, a vocal structure known in mature male Indian gharials. Extinct gavialines have repeatedly evolved potentially male-only acoustic apparatus of various shapes, illuminating the deep history of sexual selection on acoustic signalling in a slender-snouted group of crocodylians. Lastly, a cutmark analysis combined with accelerator mass spectrometry (AMS) radiocarbon dating of bone remains demonstrated that two individuals from Shang and Zhou dynasties in Guangdong, China, suffered head injuries and decapitation. Archaeological evidence together with historical accounts suggests the human-induced extinction of this unique crocodylian only a few hundred years ago. [ABSTRACT FROM AUTHOR]

Guangdong Province is one of the most developed and populous provinces in southern China. The subtype situation of hepatitis C virus (HCV) in Guangdong remains unknown. The aim of this study was to investigate and estimate the HCV subtypes in drug users (DU) using a city-based sampling strategy to better understand the characteristics of HCV transmission in Guangdong. Archived plasma samples (n = 1074) from DU who were anti-HCV positive in 2014 were selected randomly from 20 cities in Guangdong Province. Subtypes were determined based on core and/or E1 sequences using phylogenetic analysis. The distributions of HCV subtypes in DU and different regions were analyzed. A total of 8 genotypes were identified. The three main HCV subtypes in DU in Guangdong were 6a (63.0%), 3a (15.2%), and 3b (11.8%). Significant differences were discovered among different registered residency and regions but not among genders, marital status, education level, or drug use patterns. HCV subtype 3b was significantly higher in Guangdong residents than in non-Guangdong residents. In contrast, HCV subtype 6a was significantly lower in Guangdong residents than in non-Guangdong residents. Subtype 1b in eastern Guangdong (eastern) was significantly lower, while 6a was significantly higher when compared with other regions. Subtype 3a in the Pearl River Delta (PRD) region was significantly higher, while 3b was significantly lower when compared with other regions. In western Guangdong, HCV subtype 3a was significantly lower when compared with other regions. Additionally, in northern Guangdong subtypes 1b and 3b were significantly higher, while 6a was significantly lower when compared with other regions. Our study revealed the diversity and distribution of HCV subtypes in DU in nearly all the cities in Guangdong. The results provide essential information that will allow the establishment of specific intervention strategies that may help prevent HCV transmission. • Eight HCV subtypes were detected among drug users in Guangdong, China. • HCV subtype 6a has spread quickly across the whole province. • The eastern cities may be the epidemic source of 6a in Guangdong. • The north of Guangdong has a special status in transmission of HCV. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID-19) is caused by SARS-CoV-2 infection and was first reported in central China in December 2019. Extensive molecular surveillance in Guangdong, China's most populous province, during early 2020 resulted in 1,388 reported RNA-positive cases from 1.6 million tests. In order to understand the molecular epidemiology and genetic diversity of SARS-CoV-2 in China, we generated 53 genomes from infected individuals in Guangdong using a combination of metagenomic sequencing and tiling amplicon approaches. Combined epidemiological and phylogenetic analyses indicate multiple independent introductions to Guangdong, although phylogenetic clustering is uncertain because of low virus genetic variation early in the pandemic. Our results illustrate how the timing, size, and duration of putative local transmission chains were constrained by national travel restrictions and by the province's large-scale intensive surveillance and intervention measures. Despite these successes, COVID-19 surveillance in Guangdong is still required, because the number of cases imported from other countries has increased. • 1.6 million tests identified 1,388 SARS-CoV-2 infections in Guangdong by 19 March • Virus genomes can be recovered using a variety of sequencing approaches • Analyses reveal multiple viral importations with limited local transmission • Effective control measures helped reduce and eliminate chains of viral transmission Genomic and epidemiological analyses provide insights into how COVID-19 was contained in China's most populous province using a combination of surveillance and travel restriction measures. [ABSTRACT FROM AUTHOR]