Search

Abstract Purpose This study aimed to investigate the real-world use and clinical outcomes of tixagevimab/cilgavimab in China during the Omicron outbreak in late 2022. Methods This observational, real-world study included patients who received tixagevimab/cilgavimab from July 9 to December 30, 2022, in Hainan, China. Here, we report the baseline and characteristics and interim analysis results of the clinical outcomes in those receiving at least one dose of tixagevimab/cilgavimab (300 mg) for pre-exposure prophylaxis. Results Among 248 subjects who received tixagevimab/cilgavimab, 229 subjects were included in this analysis. Until March 28, 2023, the median follow-up was 95 days. The mean age of the subjects was 44.4 ± 15.9 years, 11.8% were ≥ 65 years, and 41.5% were male. Fifty-eight (25.3%) subjects had comorbidities, 16.2% subjects had key immune compromised conditions. Seventy-two (32.6%) patients had laboratory-confirmed SARS-CoV-2 infection and/or received healthcare within three months; 71/72 (98.6%) had mild disease, and one (1.4%) was moderate. No COVID-19-related intensive care unit (ICU) admissions, extracorporeal membrane oxygenation utilizations, or death occurred. Two (0.9%) patients required hospitalization. One (0.4%) serious adverse event occurred, which was considered unrelated to tixagevimab/cilgavimab. Conclusion Among Chinese patients receiving prophylactic tixagevimab/cilgavimab, the incidence of COVID-19-related hospitalization, ICU admission, or death was low during the Omicron surge. Further randomized controlled trials with larger sample sizes are needed to determine the effectiveness of tixagevimab/cilgavimab in preventing severe COVID-19 outcomes. Trial registration The study was registered with clinicaltrial.gov (NCT05917951).

The timing of flowering is an important driver of species distribution and community assembly patterns. However, we still have much to learn about the factors that shape flowering diversity (i.e., number of species flowering per period) in plant communities. One potential explanation of flowering diversity is the mid-domain effect, which states that geometric constraints on species ranges within a bounded domain (space or time) will yield a mid-domain peak in diversity regardless of ecological factors. Here, we determine whether the mid-domain effect explains peak flowering time (i.e., when most species of communities are flowering) across China. We used phenological data of 16,267 herbaceous and woody species from the provincial Flora in China and species distribution data from the Chinese Vascular Plant Distribution Database to determine relationships between the observed number of species flowering and the number of species flowering as predicted by the mid-domain effect model, as well as between three climatic variables (mean minimum monthly temperature, mean monthly precipitation, and mean monthly sunshine duration). We found that the mid-domain effect explained a significant proportion of the temporal variation in flowering diversity across all species in China. Further, the mid-domain effect explained a greater proportion of variance in flowering diversity at higher latitudes than at lower latitudes. The patterns of flowering diversity for both herbaceous and woody species were related to both the mid-domain effect and environmental variables. Our findings indicate that including geometric constraints in conjunction with abiotic and biotic predictors will improve predictions of flowering diversity patterns.

Abstract Chrozophora sabulosa Kar. & Kir. is a biennial herbaceous plant that belongs to the Euphorbiaceae family and has medicinal properties. This research aimed to identify the genetic characteristics and phylogenetic position of the Chrozophora genus within the Euphorbiaceae family. The evolutionary position of the Chrozophora genus was previously unknown due to insufficient research. Therefore, to determine the evolutionary link between C. sabulosa and other related species, we conducted a study using the NGS Illumina platform to sequence the C. sabulosa chloroplast (cp.) genome. The study results showed that the genome was 156,488 bp in length. It had a quadripartite structure consisting of two inverted repeats (IRb and IRa) of 24,649-bp, separated by an 87,696-bp LSC region and a 19,494-bp SSC region. The CP genome contained 113 unique genes, including four rRNA genes, 30 tRNA genes, and 79 CDS genes. In the second copy of the inverted repeat, there were 18 duplicated genes. The C. sabulosa lacks the petD, petB, rpl2, and rps16 intron. The analysis of simple sequence repeats (SSRs) revealed 93 SSR loci of 22 types and 78 oligonucleotide repeats of four kinds. The phylogenetic investigation showed that the Chrozophora genus evolved paraphyletically from other members of the Euphorbiaceae family. To support the phylogenetic findings, we selected species from the Euphorbiaceae and Phyllanthaceae families to compare with C. sabulosa for Ks and Ka substitution rates, InDels investigation, IR contraction and expansion, and SNPs analysis. The results of these comparative studies align with the phylogenetic findings. We identified six highly polymorphic regions shared by both families, which could be used as molecular identifiers for the Chrozophora genus (rpl33-rps18, rps18-rpl20, rps15-ycf1, ndhG-ndhI, psaI-ycf4, petA-psbJ). The cp. genome sequence of C. sabulosa reveals the evolution of plastid sequences in Chrozophora species. This is the first time the cp. genome of a Chrozophora genus has been sequenced, serving as a foundation for future sequencing of other species within the Chrozophoreae tribe and facilitating in-depth taxonomic research. The results of this research will also aid in identifying new Chrozophora species.

Many studies have confirmed that PM2.5 exposure can cause a variety of diseases. Because people spend most of their time indoors, exposure to PM2.5 in indoor environments is critical to population health. Large-population, long-term, continuous, and accurate indoor PM2.5 data are important but scarce because of the difficulties in monitoring the indoor air quality on a large scale. Model simulation provides a new research direction. In this study, an advanced machine learning model was constructed using environmental health big data to predict the daily indoor PM2.5 concentration data in 22 typical air pollution cities in China from 2013 to 2017. The test R2 value of this model reached as high as 0.89, and the RMSE of the model was 9.13. The predicted annual indoor PM2.5 concentrations of the cities ranged from 54.6 μg/m3 to 82.7 μg/m3, and showed a decreasing trend year by year. The pollution level exceeds the recommended AQG level of PM2.5 and has potential impact on human health. The results could take a breakthrough in obtaining accurate big data of indoor PM2.5 and contribute to research on the indoor air quality and human health in China. Synopsis: This study established a machine learning model and predicted indoor PM2.5 big data, which could support the research of indoor PM2.5 and health.

Steam generating heat pumps (SGHPs) offer a promising alternative to coal-fired boilers. To address the lack of general optimization strategy of autocascade SGHP (ASGHP) for variable operating conditions and variable cycle configurations, this paper models an ASGHP with the addition of an IHX and the use of steam injection instead of the injector whose performance is more sensitive under variable operating conditions. The general optimization strategy of ASGHP was analyzed and proposed using the advanced exergy analysis method to evaluate the feasibility and reliability of the system under the significant temperature lift condition comprehensively. Subsequently, an optimization analysis of the system was conducted in accordance with the proposed strategy. The results indicate that the ASGHP efficiently uses a low-temperature heat source (10–20 °C) to generate high-temperature steam, achieving a substantial temperature increase and notably lowering the compressor discharge temperature. The optimization sequence for ASGHP involves prioritizing the compressor, evaporator, and condenser in that order. The average steam mass flow rate increases by 3.2 % when the evaporator heat transfer efficiency rises by 10 % at a heat source temperature of 20 °C. Furthermore, a 5 % increase in the condenser heat transfer area results in a 4.1 % increase in the average steam mass flow rate. These results can provide theoretical guidance for the design and optimization of ASGHPs.

Phthalates are endocrine disruptors of increasing concern for human health; however, previous studies have only assessed the association between internal exposure and human health. We aimed to assess the non-carcinogenic and carcinogenic risks of non-dietary exposure to phthalates in indoor environments among primary school children and their correlations with health indicators. A study involving 54 children was conducted in Jinan, Shandong Province, China. Questionnaires and health examinations were conducted, dust in hard-to-clean corners of students’ classrooms and homes was collected, and airborne phthalates in the middle of classrooms and family living rooms were sampled. The gas-phase phthalate concentrations, individual exposure, and non-carcinogenic and carcinogenic risks were calculated. Associations were estimated using linear mixed models. The findings revealed that phthalates posed a non-carcinogenic risk to 7.4 % of the children and a moderate carcinogenic risk to 27.8 % of the children, with higher non-carcinogenic and carcinogenic risks to girls than to boys. Five phthalates were negatively correlated with body mass index, dimethyl phthalate and diethyl phthalate (DEP) were significantly correlated with waist circumference, and di-iso-butyl phthalate (DiBP) was negatively correlated with hip circumference. DiBP, di-n-butyl phthalate, and DEP, were significantly correlated with cardiovascular disease, DEP and di (2-n-butoxyethyl) phthalate were correlated with decreased lung function, and di-n-octyl phthalate influenced airway inflammation. The findings indicated that phthalate exposure may negatively impact children's health, thereby warranting further comprehensive research on the health effects of these chemicals.

Refrigerant injection techniques are usually proposed to improve the performance and reliability of compressors when a single-screw compressor applied to an air-source heat pump works at low temperatures in winter. In this study, an experimental study was conducted to present the performance comparison of the single-screw compressor in the air-source heat pump under liquid, vapor, and liquid–vapor refrigerant injection at evaporation temperatures between −19 and −8 °C. The results indicate that, when the evaporation temperature decreases from −8 to −19 °C, the heating capacity under liquid–vapor and vapor injection increases by 16.7% and 12.7%, respectively, compared with that under liquid injection and that the COPh increment under liquid–vapor injection and vapor injection is, respectively, from 11.23% to 39.21% and from 17.18% to 30.82% compared with that under liquid injection. Therefore, the liquid–vapor injection method is conducive to the operation of the air-source heat pump at a lower ambient temperature. The experimental results can provide the basis for the future design of single-screw compressors applied to air-source heat pumps.

ObjectivesThis study aimed to explore the current status and trends of acupuncture for neurodegenerative diseases (NDs) in the last decade and provide new insights for researchers in future studies.MethodsThe publications concerning acupuncture treatment for NDs published between 2014 and 2023 were extracted from the Web of Science Core Collection. We used CiteSpace and VOSviewer to analyze data on numbers of annual publications, countries, institutions, cited journals, cited authors, cited references, keywords, and citation bursts about acupuncture for NDs.ResultsA total of 635 publications were obtained from 2014 to 2023. We identified the most prolific journals, countries, institutions, authors, patterns of authorship, and the main direction of future research in the field of acupuncture for NDs in the last decade. The country, institution, and journal with the most publications are China (389 articles), Beijing University of Chinese Medicine (56 articles), and Evidence Based Complementary and Alternative Medicine (42 articles), respectively. The high-frequency keywords focused on “Alzheimer's disease,” “Parkinson's disease,” “acupuncture,” “dementia,” and “electroacupuncture.” The top five keywords in terms of centrality were “cerebral ischemia,” “acupuncture stimulation,” “fMRI,” “apoptosis,” and “deep brain stimulation.”ConclusionThe results from this bibliometric study provide insight into the research trends in acupuncture therapy for NDs, and the current status and trends of the past decade, which may help researchers confirm the current status, hotspots, and frontier trends in this field.

Vitamin D is a lipid soluble steroid hormone, which plays a critical role in the calcium homeostasis, neuronal development, cellular differentiation, and growth by binding to vitamin D receptor (VDR). Associations between VDR gene polymorphism and Alzheimer’s disease (AD), Parkinson’s disease (PD), and mild cognitive impairment (MCI) risk has been investigated extensively, but the results remain ambiguous. The aim of this study was to comprehensively assess the correlations between four VDR polymorphisms (FokI, BsmI, TaqI, and ApaI) and susceptibility to AD, PD, and MCI. Crude odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to determine the relationship of interest. Pooled analyses suggested that the ApaI polymorphism decreased the overall AD risk, and the TaqI increased the overall PD susceptibility. In addition, the BsmI and ApaI polymorphisms were significantly correlated with the overall MCI risk. Stratified analysis by ethnicity further showed that the TaqI and ApaI genotypes reduced the AD predisposition among Caucasians, while the TaqI polymorphism enhanced the PD risk among Asians. Intriguingly, carriers with the BB genotype significantly decreased the MCI risk in Asian descents, and the ApaI variant elevated the predisposition to MCI in Caucasians and Asians. Further studies are need to identify the role of VDR polymorphisms in AD, PD, and MCI susceptibility.

Hainan Tropical Rainforest National Park is located in the middle mountainous region of Hainan Province, and it has a diverse landscape with 95.56% forest coverage. Studying the evolutionary aspects of the landscape pattern in time and space in Hainan Tropical Rainforest National Park is extremely important for preserving and enhancing Hainan Province's ecological security barrier. The landscape pattern index, single-motion landscape dynamic attitude and landscape transfer matrix were used to examine the geographical and temporal evolution features of the landscape pattern of 10 land cover patterns in Hainan Tropical Rainforest National Park between 2015 and 2020. This study used ground cover data from the Hainan Tropical Rainforest National Park between 2015 and 2020 to develop a landscape pattern distribution system based on actual ecological situations. Other elements that affected the evolution of the landscape pattern in Hainan Tropical Rainforest National Park included policies, climate and other natural and human factors. The results were as follows: (1) The overall landscape fragmentation of Hainan Tropical Rainforest National Park reduced from 2015 to 2020, increasing spatial agglomeration of the landscape, decreasing integrated dynamic attitude, and generally steady development of landscape patterns. (2) The area of evergreen broad-leaved forest in the tropical rainforest increased in five years, with an increase of 531.38 km2, a decrease in fragmentation, and a positive growth trend, and the landscape tends to be concentrated in patches; on the other hand, the area of needle-leaved forest and shrubwood significantly reduced, with losses of 189.53 km2 and 294.74 km2 respectively; there was also a partial transformation of water, and the area of the water landscape had been somewhat reduced, and the patches tended to be concentrated and spread; the remainder of the landscape patterns accounted for a relatively modest amount, and developed and changed in the direction of natural succession. (3) The landscape pattern evolution of Hainan Tropical Rainforest National Park was primarily based on natural succession of the rainforest, followed by a comprehensive impact of policy, climate and other factors, which reduced human factors on the tropical rainforest landscape interference and was conducive to improving the rainforest ecosystem's self-healing capacity. To summarize, the landscape pattern of Hainan Tropical Rainforest National Park has been stable since the commencement of the pilot project, and policy direction has played an essential constructive role. The targeted conservation and restoration of the tropical rainforest landscape will help to the Hainan Tropical Rainforest National Park's sustainable development.

World natural heritage sites are some of the most important and valuable protected areas in the world, and their designation aims to give recognition to the uniqueness and protect the integrity of the sites, which are of global outstanding universal value. Understanding the global uniqueness and value of natural heritage will help to better manage and protect them, support the functioning of ecosystems, and promote sustainable development of humans and nature. A systematic review was conducted to determine the potential for the Hainan tropical rainforest to become a world natural heritage site. Based on a large number of literatures, we took the native plants, animals and vegetation communities of Hainan’s potential natural world heritage site (Hainan Tropical Rainforest National Park) as the research objects, and evaluated the global outstanding universal value of Hainan’s potential natural world heritage site from the aspects of biological ecological processes such as vegetation types, species diversity, fauna composition and endemic species. The results are as follows: (1) Hainan potential world natural heritage site has 3 653 vascular plant species. There are 540 species of terrestrial vertebrates, which account for 10%-30% of the wild animal species in the country. This indicates that biodiversity in this area is extremely high. (2) The flora found in the Hainan tropical rainforest is unique. Vegetation on Hainan Island can be categorized in the Indo-Malay rainforest group, and within the Malay region, and vegetation is tropical in nature and has a common origin with the South China mainland. This is indicative of the transition between the South China flora into the Asian rainforest. (3) The plant species specificity of flora is lower, there are only seven endemic genera in the flora, and about one out of every 10 species is endemic to the island. Lower specificity shows some characteristics of continental origin and the flora on the island are an irreplaceable element of biodiversity, and make up a valuable ecosystem. This study clarifies the outstanding universal values of the Hainan tropical rainforest and makes the case using empirical scientific evidence for nominating this area as a world natural heritage site.

Coral sand is widely encountered in coastal areas of tropical and subtropical regions. Compared with silica sand, it usually exhibits weaker performance from the perspective of engineering geology. To improve the geomechanical performance of coral sand and meet the requirement of foundation construction in coastal areas, a novel alkali activation-based sustainable binder was developed. The alkali-activated slag (AAS) binder material was composed of ground granulated blast-furnace slag (GGBS) and hydrated lime with the amendment of biochar, an agricultural waste-derived material. The biochar-amended AAS stabilized coral sand was subjected to a series of laboratory tests to determine its mechanical, physicochemical, and microstructural characteristics. Results show that adding a moderate amount of biochar in AAS could improve soil strength, elastic modulus, and water holding capacity by up to 20%, 70%, and 30%, respectively. Moreover, the addition of biochar in AAS had a marginal effect on the sulfate resistance of the stabilized sand, especially at high biochar content. However, the resistance of the AAS stabilized sand to wet-dry cycles slightly deteriorated with the addition of biochar. Based on these observations, a conceptual model showing biochar-AAS-sand interactions was proposed, in which biochar served as an internal curing agent, micro-reinforcer, and mechanically weak point.

Abstract Ionic circuits using ions as charge carriers have demonstrated great potential for flexible and bioinspired electronics. The emerging ionic thermoelectric (iTE) materials can generate a potential difference by virtue of selective thermal diffusion of ions, which provide a new route for thermal sensing with the merits of high flexibility, low cost, and high thermopower. Here, ultrasensitive flexible thermal sensor arrays based on an iTE hydrogel consisting of polyquaternium‐10 (PQ‐10), a cellulose derivative, as the polymer matrix and sodium hydroxide (NaOH) as the ion source are reported. The developed PQ‐10/NaOH iTE hydrogel achieves a thermopower of 24.17 mV K−1, which is among the highest values reported for biopolymer‐based iTE materials. The high p‐type thermopower can be attributed to thermodiffusion of Na+ ions under a temperature gradient, while the movement of OH− ions is impeded by the strong electrostatic interaction with the positively charged quaternary amine groups of PQ‐10. Flexible thermal sensor arrays are developed through patterning the PQ‐10/NaOH iTE hydrogel on flexible printed circuit boards, which can perceive spatial thermal signals with high sensitivity. A smart glove integrated with multiple thermal sensor arrays is further demonstrated, which endows a prosthetic hand with thermal sensation for human–machine interaction.

Calcareous sand is widely present in coastal areas around the world and is usually considered as a weak and unstable material due to its high compressibility and low strength. Microbial-induced calcium carbonate precipitation (MICP) is a promising technique for soil improvement. However, the commonly adopted bio-augmented MICP approach is in general less compatible with the natural soil environment. Thus, this study focuses on the bio-stimulated MICP approach, which is likely to enhance the dominance of ureolytic bacteria for longer period and thus is deemed more efficient. The main objective of this paper is to investigate the compressibility of calcareous sand treated by bio-stimulated MICP approach. In the current study, a series of one-dimension compression tests was conducted on bio-cemented sand prepared via bio-stimulation with different initial relative densities (Dr). Based on the obtained compression curves and particle size distribution (PSD) curves, the parameters including cementation content, the coefficient of compressibility (av), PSD, relative breakage (Br), and relative agglomeration (Ar) were discussed. The results showed that av decreased with the increasing cementation content. The bio-cemented sand prepared with higher initial Dr had smaller (approximately 20%–70%) av values than that with lower initial Dr. The specimen with higher initial Dr and higher cementation content resulted in smaller Br but larger Ar. Finally, a conceptual framework featuring multiple contact and damage modes was proposed.

In this paper the effect of BOFS-CCR-PG(BCP) binder was evaluated on the diffusion migration parameters of heavy metal after S/S in industrial contaminated site soil. The effective diffusion coefficient and the change of distribution coefficient of contaminated soil after S/S were investigated on a particular one-dimensional cylindrical diffusion test device, and on the basis of Fick's law theory and Pollute V6.3 calculation program. The results show that the BCP can effectively reduce the effective diffusion coefficient of Ni and Zn by 2 orders of magnitude, while the distribution coefficient is significantly improved by 2 orders of magnitude. The distribution coefficient of Ni and Zn in BCP solidified soil is 169 and 175 times that in the contaminated soil, respectively. The BCP binder can significantly improve the environmental safety of contaminated soil.

Biodiversity is and always has been an important issue in ecological research. Biodiversity can reflect niche partitioning among species at several spatial and temporal scales and is generally highest in the tropics. One theory to explain it is that low-latitude tropical ecosystems are dominated by species that are generally only distributed over a narrow area. This principle is known as Rapoport’s rule. One previously unconsidered extension of Rapoport’s rule may be reproductive phenology, where variation in flowering and fruiting length may reflect a temporal range. Herein, we collected reproductive phenology data for more than 20,000 species covering almost all angiosperm species in China. We used a random forest model to quantify the relative role of seven environmental factors on the duration of reproductive phenology. Our results showed that the duration of reproductive phenology decreased with latitude, although there was no obvious change across longitudes. Latitude explained more of the variation in the duration of flowering and fruiting phases in woody plants than in herbaceous plants. Mean annual temperature and the length of the growing season strongly influenced the phenology of herbaceous plants, and average winter temperature and temperature seasonality were important drivers of woody plant phenology. Our result suggests the flowering period of woody plants is sensitive to temperature seasonality, while it does not influence herbaceous plants. By extending Rapoport’s rule to consider the distribution of species in time as well as space, we have provided a novel insight into the mechanisms of maintaining high levels of diversity in low-latitude forests.

The cortex-to-stele ratio (CSR), as it increases from thin- to thick-root species in angiosperms, is theorised to effectively reflect a compensation for the ‘lag’ of absorption behind transportation. But it is still not known if this compensatory effect exists in gymnosperm species or governs root structure and function within species. Here, anatomical, morphological, and tissue chemical traits of absorptive roots were measured in three temperate angiosperm and three gymnosperm species. Differences in the CSR and the above functional traits, as well as their intraspecific associations, were analyzed and then compared between angiosperms and gymnosperms. At the intraspecific level, the CSR decreased with increasing root order for all species. The expected functional indication of the CSR was consistent with decreases in specific root length (SRL) and N concentration and increases in the C to N ratio (C:N ratio) and the number of and total cross-sectional area of conduits with increasing root order, demonstrating that the CSR indicates the strength of absorption and transportation at the intraspecific level, but intraspecific changes are due to root development rather than the compensatory effect. These trends resulted in significant intraspecific associations between the CSR and SRL (R2 = 0.36 ~ 0.80), N concentration (R2 = 0.48 ~ 0.93), the C:N ratio (R2 = 0.47 ~ 0.91), and the number of (R2 = 0.21 ~ 0.78) and total cross-sectional area (R2 = 0.29 ~ 0.72) of conduits in each species (p< 0.05). The overall mean CSR of absorptive roots in angiosperms was four times greater than in gymnosperms, and in angiosperms, the CSR was significantly higher in thick- than in thin-rooted species, whereas in gymnosperms, the interspecific differences were not significant (p > 0.05). This suggests that the compensation for the lag of absorption via cortex thickness regulation was stronger in three angiosperm species than in three gymnosperm species. In addition, there was poor concordance between angiosperms and gymnosperms in the relationships between CSRs and anatomical, morphological, and tissue chemical traits. However, these gymnosperm species show a more stable intraspecific functional association compared to three angiosperm species. In general, absorptive root CSRs could manifest complex strategies in resource acquisition for trees at both intra- and interspecific levels.

Beta-glucan has been shown to have a beneficial effect on gastrointestinal health. This experiment was conducted to investigate the effects of β-glucan isolated from Agrobacterium sp. ZX09 on growth performance and intestinal health of weaning pigs. A total of 108 weaned pigs (21 d of age; 6.05 ± 0.36 kg) were randomly divided into 3 groups (6 pens/group; 6 pigs/pen), and the groups were each treated with the following diets: 1) basal diet, 2) basal diet supplemented with 20 mg/kg olaquindox, 3) basal diet supplemented with 200 mg/kg β-glucan, for 21 d. Compared with the control group, pigs fed with 200 mg/kg β-glucan had greaterBW, average daily gain and duodenal villus height to crypt depth ratio (P

In aquatic systems, sediment is both a sink for persistent organic pollutants (POPs) and a potential source of POPs release. Consequently, it is important to understand the pollution characteristics and sources of polychlorinated naphthalenes (PCNs) as POPs of Stockholm Convention in sediment for control of the ecological risk. Atmospheric deposition is a potential source of PCNs in sediment. However, there is no clear report on the contribution of atmospheric deposition to PCNs in sediments. In this study, the Chaobai River in China was selected because it is an important drinking water source that is not affected by wastewater discharge. Surface sediments from the river were analyzed for 75 PCN congeners by using high resolution gas chromatography combined with high resolution mass spectrometry. The total PCNs concentration ranged from 54 to 2266 (mean: 402) pg/g. The toxic equivalent quantity of 19 PCNs in surface sediments was 9.69 × 10−2, and CN73, CN66/CN67, and CN63 had the largest contributions to this value. Dichlorinated and trichlorinated naphthalenes were the dominant homologs. The PCN data from the sediment samples in this study were combined with data for PCNs in ambient air from a literature, which has a good match with this study in both temporal and spatial scales. The contribution of atmospheric deposition to PCNs in the surface sediment was evaluated by comparing congener characteristics and correlation analysis. Our study indicated atmospheric transportation and deposition are important pathways for transport of PCNs into surface sediments.

The timing of flowering and fruiting plays a critical role in the reproduction, population size, and range of fruit-eating animals. The Hainan Tropical Rainforest National Park, China, hosts one of the world’s most endangered primate species, the Hainan gibbon (Nomascus hainanus). Understanding the phenological patterns of the principal food sources of the Hainan gibbon is crucial for the effective management of their habitats and the conservation of this threatened population. To that end, we conducted a regression analysis to better understand how climate may impact the timing and availability of fruits known to support the Hainan gibbon. We observed significant seasonal and inter-annual variations in the reproductive phenology of these fruiting species, with most species flowering from March to June and fruiting from August to December. Importantly, we found that Hainan gibbons face severe food scarcity between January and April. We show that sunshine exerts a significant effect on the flowering time, while fruiting phenology is most sensitive to temperature. We suggest that the restoration of the Hainan gibbon habitat should include planting more tree species which that produce fruit in the time of low food availability between January-April, including the species Memecylon ligustrifolium, Wrightia pubescens, Sarcosperma laurinum, Eurya ciliata, and Pouteria annamensis.

The workability, hydraulic conductivity, and mechanical properties are essential to contaminant containment performance of cementitious backfills in vertical cutoff walls at contaminated sites. This study aims to investigate the engineering properties of a novel vertical cutoff wall backfill composed of reactive magnesia (MgO)-activated ground granulated blast furnace slag (GGBS), sodium-activated calcium bentonite amended with polyacrylamide cellulose (PAC), and clean sand (referred to as MSBS-PAC). Backfills composed of MgO-activated GGBS, sodium-activated calcium bentonite, and clean sand (referred to as MSBS) were also tested for comparison purposes. A series of tests were conducted which included slump test, flexible-wall hydraulic conductivity test, and unconfined compression test. The pore size distributions of two types of backfills were investigated via the nuclear magnetic resonance (NMR) technique. The results showed the moisture content corresponding to the target slump height was higher for MSBS-PAC backfill than that for MSBS backfill. The MSBS-PAC backfill possessed lower pH, dry density, and higher void ratio at different standard curing times as compared to MSBS backfill. The unconfined compressive strength and strain at failure of the MSBS-PAC backfill were noticeable lower than those of the MSBS backfill. In contrast, the hydraulic conductivity of MSBS-PAC backfill was approximately one order of magnitude lower than that of the MSBS backfill, which was less than 10−9 m/s after 28-day and 90-day curing. Lower hydraulic conductivity of MSBS-PAC backfill was attributed to the improvement of pore structure and pore fluid environment by PAC amendment.

The fast motion of low Earth orbit (LEO) satellites provides rapid geometric changes in a short time, which can accelerate the initialization of precise point positioning (PPP). The rapid convergence of ambiguity parameters is conducive to the rapid success of ambiguity fixing. This paper presents the performance of single- and four-system combined PPP Ambiguity Resolution (AR), enhanced with an ambiguity-float solution LEO. Two LEO constellations were designed: L was a typical polar orbit constellation, with a higher number of visible satellites at high latitudes than at low and middle latitudes; and M was designed to compensate for the lack of visible satellites at low and middle latitudes. The ground observation data of the LEO satellites at the MGEX stations were simulated. Because the global navigation satellite systems (GNSSs) were fully operational, the GNSS data were real observation data from the MGEX stations. Based on the daily observation datasets collected at 258 stations in the global MGEX observation network over three days (from 1 January to 3 January 2022), in addition to the LEO simulation data, we evaluated the positioning performance of LEO ambiguity-float solution-enhanced PPP ambiguity resolution and compared it with LEO-enhanced PPP. The L+M mixed constellation was able to reduce the time to first fix (TTFF) of the four-system combined PPP-AR to 5 min, and four LEO satellites were sufficient to achieve this. L+M mixed constellation was able to reduce the convergence time of the four-system combined PPP to 2 min. Unlike PPP-AR, PPP required more LEO satellites for augmentation to saturate.

Studying the distribution of samara species is of ecological and economic significance. This information helps us with understanding species dispersal mechanisms, evaluating the risk of invasive species, and the management of ecological forests. However, limited research has explored, on a large scale, the geographic distribution of samara species and their influential abiotic factors. Here, we use the distribution data of 835 vascular samara species and growth form data to explore their geographic patterns in China and the environmental determinants. We divided China into 984 grid cells and examined the relationship between the proportion of samara species and climate variables using both ordinary and spatial linear regressions for each grid cell. Total samara species richness is higher in southern China in low altitude regions and the proportion of woody samara species is significantly higher than that of herbaceous samara species. The proportion of woody samara species is higher in the northeast regions where precipitation is sufficient, winters are dry and mild, and temperature seasonality and land surface relief degree values are high. Annual precipitation and temperature seasonality are the most important climatic drivers for the distribution of woody samara species. In contrast, herbaceous samara species prefer to distribute to the areas where climate is warm and dry but have higher temperature seasonality. Temperature related variables (mean annual temperature, mean diurnal range, and temperature seasonality) are the most important drivers for the distribution of herbaceous samara species. Samara species can better adapt to climatic regions with large temperature fluctuations and dry winters. The present distribution patterns of samara species are formed by the combined adaptation of fruit traits and growth form to climate. This work contributes to predictions of the global distribution of samara species under future climate change scenarios and conservation and management for the samara species.

BeiDou Global Navigation Satellite System (BDS-3) broadcasts multifrequency signals that offer more choices of frequencies and more signal combinations for positioning. This paper analyzes the effect of timing group delay (TGD) and differential code bias (DCB) of BDS-3 on the corresponding triple-frequency positioning. The triple-frequency observation models of BDS-3 are summarized and the DCB correction models are derived for the four different frequency combinations of triple-frequency ionospheric-free (IF) combination (IF123), two dual-frequency IF combinations (IF1213) and triple-frequency uncombined (UC123) positioning modes. Standard point positioning (SPP) and precise point positioning (PPP) experiments were conducted using 30 days of observations from 25 multi-GNSS experiment (MGEX) stations. The results show that the TGD/DCB correction has a significant impact on the accuracy of SPP. The positioning accuracy using IF123 and IF1213 models improved by about 73~90% after TGD correction, in comparison to a 27~30% improvement achieved using the UC123 model. In addition, the correction effect of DCB is slightly better than TGD. The DCB correction significantly improves accuracy in the initial epoch of the PPP, which helps the convergence of the filtering and reduces the convergence time. The average convergence times of IF123, IF1213 and UC123 are 26.1, 26.9 and 38.3 min, respectively, which are reduced by 6.79, 2.54 and 8.59% with DCB correction. The pseudorange residuals are closer to zero-mean random noise after DCB correction. Furthermore, the DCB affects the evaluation of the inter-frequency bias (IFB), ionospheric delay and floating ambiguity parameters. However, the tropospheric delay is almost unaffected by DCB.

Summary: Recent studies have shown that PM2.5 may activate the hypothalamus-pituitary-adrenal (HPA) axis by inducing hormonal changes, potentially explaining the increase in neurological and cardiovascular risks. In addition, an association between PM2.5 and gut microbiota and metabolites was established. The above evidence represents crucial parts of the gut-brain axis (GBA). In view of this evidence, we proposed a hypothesis that PM2.5 exposure may affect the HPA axis through the gastrointestinal tract microbiota pathway (GBA mechanism), leading to an increased risk of neurological and cardiovascular diseases. We conducted a real-world prospective repeated panel study in Jinan, China. At each visit, we measured real-time personal PM2.5 and collected fecal and blood samples. A linear mixed-effects model was used to analyze the association between PM2.5 and serum biomarkers, gut microbiota, and metabolites. We found that PM2.5 was associated with increased serum levels of hormones, especially the adrenocorticotropic hormone (ACTH) and cortisol, which are reliable hormones of the HPA axis. Gut microbiota and tryptophan metabolites and inflammation, which are important components of the GBA, were significantly associated with PM2.5. We also found links between PM2.5 and changes in the nervous and cardiovascular outcomes, e.g., increases of 19.77% (95% CI: −36.44, 125.69) in anxiety, 1.19% (95% CI: 0.65, 1.74) in fasting blood glucose (FBG), 2.09% (95% CI: 1.48, 2.70) in total cholesterol (TCHOL), and 0.93% (95% CI: 0.14, 1.72) in triglycerides (TG), were associated with 10 μg/m3 increase in PM2.5 at the lag 0–72 h, which represent the main effects of GBA. This study indicated the link between PM2.5 and the microbiota GBA for the first time, providing evidence of the potential mechanism for PM2.5 with neurological and cardiovascular system dysfunction.

The exposome overhauls conventional environmental health impact research paradigms and provides a novel methodological framework that comprehensively addresses the complex, highly dynamic interplays of exogenous exposures, endogenous exposures, and modifiable factors in humans. Holistic assessments of the adverse health effects and systematic elucidation of the mechanisms underlying environmental exposures are major scientific challenges with widespread societal implications. However, to date, few studies have comprehensively and simultaneously measured airborne pollutant exposures and explored the associated biomarkers in susceptible healthy elderly subjects, potentially resulting in the suboptimal assessment and management of health risks. To demonstrate the exposome paradigm, we describe the rationale and design of a comprehensive biomarker and biomonitoring panel study to systematically explore the association between individual airborne exposure and adverse health outcomes. We used a combination of personal monitoring for airborne pollutants, extensive human biomonitoring, advanced omics analysis, confounding information, and statistical methods. We established an exploratory panel study of Biomarkers of Air Pollutant Exposure in Chinese people aged 60–69 years (China BAPE), which included 76 healthy residents from a representative community in Jinan City, Shandong Province. During the period between September 2018 and January 2019, we conducted prospective longitudinal monitoring with a 3-day assessment every month. This project: (1) leveraged advanced tools for personal airborne exposure monitoring (external exposures); (2) comprehensively characterized biological samples for exogenous and endogenous compounds (e.g., targeted and untargeted monitoring) and multi-omics scale measurements to explore potential biomarkers and putative toxicity pathways; and (3) systematically evaluated the relationships between personal exposure to air pollutants, and novel biomarkers of exposures and effects using exposome-wide association study approaches. These findings will contribute to our understanding of the mechanisms underlying the adverse health impacts of air pollution exposures and identify potential adverse clinical outcomes that can facilitate the development of effective prevention and targeted intervention techniques.

The swelling capacity of novel hydrophilic gaskets used in geomembrane cutoff walls and infrastructures is critical for decreasing the flow rates of contaminated groundwater. This study investigated the swelling behavior, relaxation characteristics, flow rates, and micro-morphology of a hydrophilic gasket with different testing liquids. The radial swelling tests were performed using a device modified from single-lever consolidation instrument. A flow rates model apparatus was manufactured and employed to measure the flow rates of the poor-sealing hydrophilic gasket. According to the test results, the swelling ratio of the hydrophilic gaskets soaked in the DIW were the highest, followed by the NaCl solution, the MSW landfill leachate, and the CaCl2 solution. Relaxation phenomena appeared in all the specimens regardless of the testing liquids. The flow rates of the specimens penetrated with DIW, NaCl, and CaCl2 decreased to a stable state, and then increased extremely slowly to stable values. Moreover, self-healing of the hydrophilic gasket was observed. The micro-morphology indicated that sodium polyacrylate (PAAS) with insufficient expansion could separate from the matrix under high multivalent ionic strength or loading pressure conditions. Therefore, it is critical to develop the modified hydrophilic gasket with resistance to contaminated groundwater for a better barrier performance for use in contaminated sites and infrastructures.

In order to accommodate more intermittent renewable energy in coal-dominated power systems, conventional thermal power plants need to improve their operational flexibility to balance the energy system at all times. However, flexible operation of coal-fired power plants could reduce energy efficiency and increase CO2 and pollutant emission, so it is important to consider environmental implications and optimize the dispatch of wind and coal power units in the system. In this paper, based on the output profile of wind power, a wind power peak (T, H) simulation model based on Gaussian distribution was established. Using a high-proportion wind power wind–coal combined base load power generation system as an example, the economical and environmentally friendly unit operation based on different wind power penetration was studied by simulation, and the decision strategy was established. Wind energy curtailment boundary was determined with power generation cost, energy consumption, CO2 and pollutant emissions as decision targets, respectively. Weekly scale results indicate that incorporating energy consumption and pollutant emissions into consideration will lead to different decision-making strategies compared with only targeting minimizing wind curtailment. This paper established a decision-making model of wind–coal system operation strategy based on economy and environmental criteria. This work directly contributes to real system operation and is of great significance for future scheduling/dispatch studies of actual power systems.

Questions: Documenting the patterns and drivers of functional trait distributions at large spatial scales is key to our fundamental understanding of the composition of plant assemblages. However, phylogeographic patterns of fruit development time (FDT, the difference between flowering and fruiting dates) have remained unstudied. Here we compiled reproductive phenology (flowering and fruiting time) and species distribution data for 6838 angiosperm species in China to explore whether FDT is more phylogenetically conserved as latitude and elevation increase, whether the phylogenetic signal of FDT correlates with phylogenetic structure and potential climatic drivers across China, and whether the environmental determinants of phylogenetic signal of FDT differ between herbaceous and woody species. Location: China Methods: We divided China into 268 200 × 200 km grid cells and calculated the phylogenetic signals of FDT in each grid cell using pagel’s λ. We then regressed the phylogenetic signals of FDT as a function of either latitude or elevation, individually. We examined the relationship between phylogenetic signals of FDT and climate variables using both ordinary and spatial linear regressions. We also examined the relationship between the phylogenetic signal of FDT and either net relatedness index (NRI) or clade age of each grid-cell. Results: We found that phylogenetic signals in FDT increased as elevation and latitude increased. The Pagel’s λ of FDT was negatively correlated with clade age but positively correlated with NRI. Precipitation in the wettest quarter was the primary variable affecting the phylogenetic signal for herbaceous species, while minimum temperature of the coldest month and temperature seasonality were the two most important climatic factors for woody species. Conclusions: Strength of phylogenetic conservatism of FDT is greater at higher latitudes and elevations. The latitudinal and elevational patterns, where mean clade age of species lowers as temperature decreases, and angiosperm assemblages tend to be more phylogenetically clustered at higher elevations and higher latitudes, could be explained by the Tropical Niche Conservatism hypothesis. The phylogenetic signals of herbs and of woody plants are triggered by different climatic drivers. Our findings have important implications for the study of large-scale geographical gradients in plant species richness, phylogenetic diversity and community assembly.

Combination therapy using Western and traditional Chinese medicines has shown notable effects on coronavirus disease 2019 (COVID-19). The He-Jie-Shen-Shi decoction (HJSS), composed of Bupleurum chinense DC., Scutellaria baicalensis Georgi, Pinellia ternata (Thunb.) Makino, Glycyrrhiza uralensis Fisch. ex DC., and nine other herbs, has been used to treat severe COVID-19 in clinical practice. The aim of this study was to compare the clinical efficacies of HJSS combination therapy and Western monotherapy against severe COVID-19 and to study the potential action mechanism of HJSS. From February 2020 to March 2020, 81 patients with severe COVID-19 in Wuhan Tongji Hospital were selected for retrospective cohort study. Network pharmacology was conducted to predict the possible mechanism of HJSS on COVID-19-related acute respiratory distress syndrome (ARDS). Targets of active components in HJSS were screened using the Traditional Chinese Medicine Systems Pharmacology (TCMSP) and PharmMapper databases. The targets of COVID-19 and ARDS were obtained from GeneCards and Online Mendelian Inheritance in Man databases. The key targets of HJSS in COVID-19 and ARDS were obtained based on the protein–protein interaction network (PPI). Kyoto Encyclopedia of Genes and Genomes analysis (KEGG) was conducted to predict the pathways related to the targets of HJSS in COVID-19 and ARDS. A “herb-ingredient-target-pathway” network was established using Cytoscape 3.2.7. Results showed that the duration of the negative conversion time of nucleic acid was shorter in patients who received HJSS combination therapy. HJSS combination therapy also relieved fever in patients with severe COVID-19. Network pharmacology analysis identified interleukin (IL) 6, tumor necrosis factor (TNF), vascular endothelial growth factor A (VEGFA), catalase (CAT), mitogen-activated protein kinase (MAPK) 1, tumor protein p53 (TP53), CC-chemokine ligand (CCL2), MAPK3, prostaglandin-endoperoxide synthase 2 (PTGS2), and IL1B as the key targets of HJSS in COVID-19-related ARDS. KEGG analysis suggested that HJSS improved COVID-19-related ARDS by regulating hypoxia-inducible factor (HIF)-1, NOD-like receptor, TNF, T cell receptor, sphingolipid, PI3K-Akt, toll-like receptor, VEGF, FoxO, and MAPK signaling pathways. In conclusion, HJSS can be used as an adjuvant therapy on severe COVID-19. The therapeutic mechanisms may be involved in inhibiting viral replication, inflammatory response, and oxidative stress and alleviating lung injury. Further studies are required to confirm its clinical efficacies and action mechanisms.

The cover systems in contaminated sites have some problems, including desiccation cracks, which would lead to degradation of the barrier performance. This study presented a systemic laboratory experimental investigation on the liquid–plastic limit, moisture retention, hydraulic conductivity (k), and gas diffusion barrier properties of amended compacted clay by attapulgite and diatomite for controlling desiccation cracks and migration of water and volatile organic compounds (VOCs). The results showed that the attapulgite could enhance the moisture retention and liquid limit of amended compacted clay. Diatomite could reduce the gas diffusion coefficient (Dθ) significantly. The compacted clay amended by the dual-additives component of attapulgite and diatomite could enhance the liquid limit, moisture retention percent, gas barrier property, and hydraulic performance compared with the unamended clay. Based on the experimental data obtained, the dosage of additives was targeted to be 5%. The moisture retention percent of dual-additives (attapulgite 4% and diatomite 1%) amended clay increased by 82%, the k decreased by 25%, and the Dθ decreased by 42% compared with unamended clay. Scanning electron microscopy (SEM), BET-specific surface area test method (BET), Mercury Intrusion Porosimetry (MIP), and thermogravimetric analysis (TGA) indicated the enhancement mechanism of additives-amended compacted clay.

Reproductive plant phenology, such as the seasonal timing of flowering or fruiting, influences many aspects of tropical forest communities, but there are few studies examining potential drivers of phenological patterns, especially in south China. We explored phenological patterns in Hainan Tropical Rainforest National Park (HNNP) in China and their major climatic and biotic drivers, based on phenological and distribution data for >2000 species from the Flora of Hainan. Specifically, we address the following questions: (1) What are the phenological patterns for all species in HNNP and for Hainan gibbon food plants only? (2) What are the environmental drivers of reproductive phenology? (3) Whether the flowering and fruiting dates are phylogenetic conserved? (4) Does reproductive phenology vary with functional groups, like growth forms, pollination modes and fruit types? Our results show flowering peaks in late spring and early summer, while fruiting phenology was concentrated during late summer and fall. Closely related species tend to have similar flowering and fruiting dates. The number of flowering species was primary controlled by mean maximum monthly temperature while minimum monthly temperature was the most important variable in shaping fruiting patterns of all species. For fruiting of gibbon food plants, mean monthly precipitation was the most important variable. Our study found January to May was food shortage period, which has important implications for Hainan gibbon conservation. We should take targeted ecological restoration by planting gibbon food species with phenologies between January and May, and take targeted provisioning to attract gibbons into a new habitat by providing fruits between January and May.

Reproductive phenology is sensitive to climatic changes and is associated with species functional types, distribution ranges, and their corresponding climatic niches. Phylogenetic niche conservatism in reproductive phenology also constrains its diversity and the distribution of species. Therefore, we assessed the effects of photosynthetic pathway, life history, phylogeny, and climatic niche on reproductive phenology. For 190 Poaceae species in subtropical China, we compiled data on flowering onset and reproductive period, functional type (photosynthetic pathway and life history), and 18 climatic variables across the species’ global distributions and used phylogenetic models to determine associations. We found strong phylogenetic signals in flowering onset but not in reproductive period. Photosynthetic pathway and life history have significant interactive effects on both flowering onset and reproductive period, such that C3 annual grasses flowered the earliest and had the longest reproductive period. We found that species with wider climatic niches would flower earlier and have longer reproductive periods. Specifically, species that experience wider ranges of mean annual precipitation and coldest-month temperatures would flower earlier, and species with higher mean annual temperature and wider ranges of wettest-quarter precipitation have a longer reproductive period. This study finds that the diversity of reproductive phenology among subtropical grasses is constrained by evolution and climatic niche and that photosynthetic pathway and life history have an interactive effect on the timing and the duration of reproduction.

Personal exposure to air pollution is affected by its concentration in the microenvironment and individual time-activity patterns. To investigate personal black carbon (BC) exposure levels and identify their potential determinants, we conducted a panel study among 67 elderly residents aged 60–69 years in Jinan, China. Personal BC exposure was measured using portable real-time monitors, while corresponding ambient BC concentrations and meteorological conditions were also collected from the local central site. Time-activity and household characteristics were recorded. A linear mixed-effects model was used to identify potential determinants of personal BC exposure. The daily average personal BC exposure concentration was 4.1 ± 2.0 μg/m3 (±standard deviation, SD), which was significantly lower than the ambient concentration (4.6 ± 2.5 μg/m3) (p

The southwestern mountains of Hainan Island are distributed in the southernmost tropical karst landscape of China, and the unique hydrological structure and frequent solifluction droughts lead to double water stress for local plants. Highly heterogeneous water environments affect the water–use characteristics of plants. Plants develop local adaptative mechanisms in response to changes in the external environment. In this paper, hydrogen–oxygen and carbon stable isotope technology, and physiological index measurements were applied to determine the leaf traits, water–use efficiency, and photosynthetic characteristics of Impatiens hainanensis leaves in dry and foggy seasons, hoping to expound the adaptation mechanism of I. hainanensis leaves to the water dynamics in dry and foggy seasons. In dry and foggy seasons (November 2018 to April 2019), the leaves of I. hainanensis at low and medium altitudes have the following combination of traits: larger leaf dry weights, leaf areas, and specific leaf areas; smaller leaf thicknesses and leaf dry matter contents; and higher chlorophyll contents. In comparison, the leaves of I. hainanensis at high altitudes have the following combination of traits: smaller leaf dry weights, leaf areas, and specific leaf areas; larger leaf thicknesses and leaf dry matter contents; and lower chlorophyll contents. The leaves of I. hainanensis can absorb fog water through their leaves. When the leaves are sprayed with distilled water, the water potential is low, the water potential value gradually increases, and the leaves have a higher rate of water absorption. The leaves of I. hainanensis at low and medium altitudes have the following water–use characteristics: high photosynthesis, high transpiration, and low water–use efficiency. At high altitudes, the Pn of I. hainanensis decreases by 8.43% relative to at low altitudes and by 7.84% relative to at middle altitudes; the Tr decreased by 4.21% relative to at low altitudes and by 3.38% relative to at middle altitude; the WUE increased by 16.61% relative to at low altitudes and increased by 40.79% relative to at middle altitudes. The leaves of I. hainanensis at high altitudes have the following water–use characteristics: low photosynthesis, low transpiration, and high water–use efficiency. I. hainanensis develop different physiological mechanisms of water adaptation by weighing the traits of the leaves and their use of light and water to obtain resources during dry and foggy seasons.

Background: Particle air pollution has adverse health effects, and low-cost monitoring among a large population group is an effective method for performing environmental health studies. However, concern about the accuracy of low-cost monitors has affected their popularization in monitoring projects. Objective: To calibrate a low-cost particle monitor (HK-B3, Hike, China) through a controlled exposure experiment. Methods: Our study used a MicroPEM monitor (RTI, America) as a standard particle concentration measurement device to calibrate the Hike monitors. A machine learning model was established to calibrate the particle concentration obtained by the low-cost PM2.5 monitors, and ten-fold validation was used to test the model. In addition, we used a linear regression model to compare the results of the machine learning model. A calibration method was established for the low-cost monitors, and it can be used to apply the monitors in future air pollution monitoring projects. Results: The values of the random forest model calibration results and observations were more condensed around the regression line y = 0.99x + 0.05, and the R squared value (R2 = 0.98) was higher than that for the linear regression (R2 = 0.87). The random forest model showed better performance than the traditional linear regression model. Conclusions: Our study provided an effective calibration method to support the accuracy of low-cost monitors. The machine learning method based on the calibration model established in our study can increase the effectiveness of future air pollution and health studies. Keywords: PM2.5, Low-cost, Monitor, Calibration, Random forest model

Following the theoretical work in Part I, in this experimental study, the robustness, temporal resolution, and the narrow scan performance of the proposed wavelength modulation-direct absorption spectroscopy (WM-DAS) method are experimentally validated in a high-temperature tube furnace. The electromagnetic and other random-frequency noises can be effectively eliminated by extracting the characteristic spectra of the light intensity. The performance of WM-DAS with modulation frequencies from 0.1 to 100 kHz and scan indexes from 3.3 to 11.1 are also investigated at atmospheric pressure. The proposed method produces accurate line profile and high SNR over 500 consistently even with a weak absorption. As for real applications, the spectral line parameters of CO at 4300.6999 cm−1 including the collisional broadening, Dicke narrowing, and their dependence on temperature are measured. Furthermore, the high-speed measurement (1 ms) of the temperature and CO concentration of a McKenna flat flame are demonstrated.

A wide-range, calibration-free tunable diode laser spectrometer is established by combining wavelength modulation and direct absorption spectroscopy (WM-DAS) with continuous wave cavity ringdown spectroscopy (CW-CRDS). This spectrometer combines the benefits of absolute concentration measurements, wide range, and high speed, using WM-DAS with enhanced noise reduction in CW-CRDS. The accurate baseline ringdown time, τ0, is calculated by the absorption peak (measured by WM-DAS) and the ringdown time containing gas absorption information (measured by CW-CRDS at the center wavelength of the spectral line). The gas concentration is obtained without measuring τ0 in real time, thus, greatly improving the measuring speed. A WM-DAS/CW-CRDS spectrometer at 1.57 μm for CO detection was assembled for experimental validation of the multiplexing scheme over a concentration ranging from 4 ppm to 1.09% (0.1 MPa, 298 K). The measured concentration of CO at 6374.406 cm−1 shows that the dynamic range of this tunable diode laser absorption spectrometer is extendable up to five orders of magnitude and the corresponding precision is improved. The measurement speed of this spectrometer can extend up to 10 ms, and the detection limit can reach 35 ppb within 25 s.

The absorbance is of great importance in the tunable diode laser absorption spectroscopy (TDLAS) as it contains information of both gas properties and spectroscopic parameters. A novel, calibration-free wavelength modulation-direct absorption spectroscopy (WM-DAS) is proposed and experimentally verified in this two-part paper. This method combines the capability of absorbance measurement from DAS and the advantages of enhanced noise rejection and high sensitivity from WMS. In this Part I, we focus on the full theoretical basis and procedures of this method from the following three aspects: the high-accuracy characterizations of laser frequency and intensity, noise rejection ability by extracting the characteristic spectra through the fast Fourier transform (FFT) of the light intensity, and the simultaneous fitting strategy for both baseline and absorbance. The preliminary validation experiment of CO transition at 4300.6999 cm−1 in a static gas cell shows the high accuracy of the proposed method.

The distribution of plant species along environmental gradients is expected to be predictable based on organismal function. Plant functional trait research has shown that trait values generally vary predictably along broad-scale climatic and soil gradients. This work has also demonstrated that at any one point along these gradients there is a large amount of interspecific trait variation. The present research proposes that this variation may be explained by the local-scale sorting of traits along soil fertility and acidity axes. Specifically, we predicted that trait values associated with high resource acquisition and growth rates would be found on soils that are more fertile and less acidic. We tested the expected relationships at the species-level and quadrat-level (20 × 20 m) using two large forest plots in Panama and China that contain over 450 species combined. Predicted relationships between leaf area and wood density and soil fertility were supported in some instances, but the majority of the predicted relationships were rejected. Alternative resource axes, such as light gradients, therefore likely play a larger role in determining the interspecific variability in plant functional traits in the two forests studied.

The extent to which environmental heterogeneity can account for tree species coexistence in diverse ecosystems, such as tropical rainforests, is hotly debated, although the importance of spatial variability in contributing to species co-existence is well recognized. Termites contribute to the micro-topographical and nutrient spatial heterogeneity of tropical forests. We therefore investigated whether epigeal termite mounds could contribute to the coexistence of plant species within a 50 ha plot at Pasoh Forest Reserve, Malaysia. Overall, stem density was significantly higher on mounds than in their immediate surroundings, but tree species diversity was significantly lower. Canonical correspondence analysis showed that location on or off mounds significantly influenced species distribution when stems were characterized by basal area. Like studies of termite mounds in other ecosystems, our results suggest that epigeal termite mounds provide a specific microhabitat for the enhanced growth and survival of certain species in these species-rich tropical forests. However, the extent to which epigeal termite mounds facilitate species coexistence warrants further investigation.

Objective: To compare the efficacy and safety of neoadjuvant chemotherapy combined with concurrent chemoradiotherapy (NACT+CCRT) vs. concurrent chemoradiotherapy (CCRT) in locally advanced cervical cancer (LACC) patients with large tumor masses. Methods: LACC patients with localized tumor diameter >4 cm, were randomly allocated in an unblinded 1:1 ratio to NACT+CCRT or CCRT groups. Patients in the NACT+CCRT group were given paclitaxel combined with cisplatin (TP) NACT every 3 weeks for 2 cycles, followed by CCRT, with the chemotherapy regimen the same as for NACT. CCRT group were given CCRT with the same as for NACT. Results: From March 1, 2019, to June 30, 2021, 146 patients were included in the final analysis. Sixty-eight (93.2%) patients in the NACT+CCRT group and 66 (90.4%) patients in the CCRT group completed the expected treatment course. The complete response (CR) rate in the NACT+CCRT group was significantly higher than in the CCRT group (87.7% vs. 67.6%, Χ²=54.540, p=0.000). In the NACT+CCRT group, the 1- and 2-year overall survival (OS) rates were significantly higher than those in the CCRT group (96% vs. 89% and 89% vs. 79%, Χ²=5.737, p=0.017). Additionally, the rate of recurrences and distant metastases was significantly lower in the NACT+CCRT group than in the CCRT group (4.11% vs. 7.35%, Χ²=4.059, p=0.021). Most treatment-related adverse events in both groups were grade 3. Conclusion: Compared to CCRT, NACT+CCRT might improve the treatment completion rate, increase CR rate and 1- and 2-year OS rates, and reduce distant metastases rate for LACC patients with large tumor masses. [ABSTRACT FROM AUTHOR]