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2.
Sci Rep ; 9(1): 14563, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601927

RESUMO

Research has shown that varying spatial scale through the selection of the total extent of investigation and the grain size of environmental predictor variables has effects on species distribution model (SDM) results and accuracy, but there has been minimal investigation into the interactive effects of extent and grain. To do this, we used a consistently sampled range-wide dataset of giant panda occurrence across southwest China and modeled their habitat and distribution at 4 extents and 7 grain sizes. We found that increasing grain size reduced model accuracy at the smallest extent, but that increasing extent negated this effect. Increasing extent also generally increased model accuracy, but the models built at the second-largest (mountain range) extent were more accurate than those built at the largest, geographic range-wide extent. When predicting habitat suitability in the smallest nested extents (50 km2), we found that the models built at the next-largest extent (500 km2) were more accurate than the smallest-extent models but that further increases in extent resulted in large decreases in accuracy. Overall, this study highlights the impacts of the selection of spatial scale when evaluating species' habitat and distributions, and we suggest more explicit investigations of scale effects in future modeling efforts.

3.
Technol Health Care ; 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31594271

RESUMO

BACKGROUND: Few studies have investigated interleukin (IL)-33 as a potential proinflammtory cytokine in the joint cavity following subchondral fracture occurring during osteonecrosis of the femoral head (ONFH). OBJECTIVE: The aim of the present study was to investigate whether IL-33 and other proinflammtory cytokines, in addition to cartilage degeneration, were elevated in the joint cavity following subchondral fracture. METHODS: IL-33 levels were analyzed in the plasma, synovial fluid, and bone marrow aspirate, and the levels of IL-6, IL-17, IL-1ß, tumor necrosis factor (TNF)-α, matrix metallopeptidase (MMP)-13, and carboxy-terminal telopeptides of type II collagen (CTX-II) in synovial fluid were also quantitated to compare the levels of these proteins between stages II and III. Macro- and microscopic articular cartilage were evaluated and compared between stages II and III in the same patient. Moreover, immunohistochemical staining of MMP-13 and Col-II were examined. RESULTS: Of the 33 patients enrolled in the present study, 15 had hips in stage II and 18 had hips in stage III. IL-33 levels in all three sample types were significantly higher in stage III. Synovial fluid IL-6 and CTX-II levels were significantly higher in stage III. A clear step-off region in the weight-bearing area was macroscopically observed in the stage III femoral head. Microscopic evaluation showed symmetrical cartilage matrix deposition around the chondrocytes in the stage II articular cartilage, unlike that in stage III. Immunohistochemical staining of the stage III articular cartilage samples revealed positive MMP-13 staining in chondrocytes and decreased Col-II deposition in the matrix. CONCLUSIONS: The present study revealed elevated IL-33 and IL-6 levels and cartilage degeneration in stage III ONFH.

4.
J Occup Environ Hyg ; : 1-8, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31647753

RESUMO

Health-based aerosol sampling should reflect how particles penetrate and deposit in various regions of the human respiratory system. Therefore, size-selective sampling should be adopted when monitoring aerosol concentration in the atmosphere. However, cyclone samplers, the most commonly used respirable sampler type in the workplace, show specific particle size-dependent bias toward the international respirable convention. Additionally, cyclone samplers are vulnerable to the dust loading effect resulting in an underestimation of respirable particulate matter. In the previous study, a virtual cyclone has been employed to overcome the dust loading effect, but still had the disadvantage of high aerosol penetration of large particle sizes. Therefore, in this work, the effects of key dimensions of virtual cyclones including chamber width (or inlet width), chamber size and inlet height on the separation performance were further studied and the configurations of virtual cyclones were modified to best fit the ISO/CEN/ACGIH respirable convention. Experimental results demonstrated that a better match with the ISO/CEN/ACGIH respirable convention curve can be achieved by increasing the chamber width to over 20 mm. Moreover, the new virtual cyclones can operate at a flow rate up to 21.5 L/min to collect more respirable particulate matter for the increasingly stringent respirable dust standards. The new virtual cyclones demonstrate accurate and constant measurement of the respirable dust for exposure assessment.

5.
J Hazard Mater ; 384: 121315, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31581013

RESUMO

Municipal solid waste incineration fly ash (MSWI-FA) is classified as hazardous waste that requires an effective processing method. This study proposed an innovative technique process, co-reduction of MSWI-FA and red mud followed by magnetic separation, to prepare crude alloy and cleaned slag. In this process, MSWI-FA acted not only as a reductant to reduce metal minerals in MSWI-FA and red mud to form an alloy, but also as a calcium additive to enhance the reduction of metal minerals and alter the melting point of the CaO-SiO2-Al2O3 system. Under optimal conditions, 85.52% Fe, 80.10% Cu, 92.96% Ni, and 66.74% Cr can be recovered in the form of a Fe-Cu-Ni-Cr alloy. The Fe-Cu-Ni-Cr alloy containing 96.47% Fe, 0.81% Cu, 0.65% Ni, and 0.42% Cr can be used for weathering steel production. Other heavy metals, including Cd, Pb, and Zn, were removed via volatilization. The toxicity characteristic leaching procedure test indicated that the leaching toxicity of the cleaned slag was substantially below the standard limits. The characteristics of the cleaned slag were similar to those of ground granulated blast furnace slag, suggesting its potential application in cement production.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31661054

RESUMO

A Gram-stain-negative, rod-shaped bacterium, motile by means of a single polar flagellum, designated S-6-2T, was isolated from petroleum polluted river sediment in Huangdao, Shandong Province, PR China. The 16S rRNA gene sequence analysis revealed that S-6-2T represented a member of the genus Pseudomonas, sharing the highest sequence similarities with Pseudomonas parafulva (97.5 %) and Pseudomonas fulva (97.5 %). Phylogenetic analysis based on 16S rRNA gene, concatenated 16S rRNA, gyrB, rpoB and rpoD genes and genome core-genes indicated that S-6-2T was affiliated with the members of the Pseudomonas pertucinogena group. The average nucleotide identity (ANI) and genome-to-genome distance between the whole genome sequences of S-6-2T and closely related species of the genus Pseudomonas within the P. pertucinogena group were less than 77.94 % and 20.5 %, respectively. Differences in phenotypic characteristics were also found between S-6-2T and the closely related species. The major cellular fatty acids (>10 %) were summed feature 8 (C18 : 1ω7c/ C18  : 1ω6c), C16 : 0, C17 : 0cyclo and C12 : 0. The predominant respiratory quinone was ubiquinone 9. The major polar lipids were diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), one unidentified lipid (L1), two unidentified phospholipids (PL1 and PL2) and an aminophospholipid (APL). The DNA G+C content of the genome of S-6-2T was 60.1 mol%. On the basis of the evidence from the polyphasic taxonomic study, strain S-6-2T can be classified as representative of a novel species of the genus Pseudomonas, for which the name Pseudomonas phragmitis sp. nov. is proposed. The type strain is S-6-2T (=CGMCC 1.15798T=KCTC 52539T).

7.
Artigo em Inglês | MEDLINE | ID: mdl-31664677

RESUMO

OBJECTIVE: This study examined the factors that predict recommended screening compliance to cervical, breast, and colorectal cancers in low-income African American women. It also examined obstacles to screenings by geographic region and screening status. METHODS: As a part of the Meharry Community Networks Program (CNP) needs assessment, a 123-item community survey was administered to assess demographic characteristics, health care access and utilization, and screening practices for various cancers in low-income African Americans. For this study, only African American women 40 years and older (n = 308) were selected from the Meharry CNP community survey database. RESULTS: There were several predictors to recommended screening such as being employed and having health insurance (P < 0.05). Additionally, the obstacles to screening posed a similar level of difficulty for participants from different geographic areas. DISCUSSION: Sociodemographic differences and obstacles of screening need to be addressed in educational interventions aimed at improving cancer screenings.

8.
Appl Opt ; 58(19): 5213-5218, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503616

RESUMO

A tunable external cavity diode laser (ECDL) with high side-mode suppression ratio (SMSR) is demonstrated. The ECDL is operated at both strong and weak feedback steady states with single longitudinal mode. Compared with the strong feedback mode, the SMSR of the weak feedback mode is significantly enhanced by rotating the grating along the axis of the incident beam, which changes the polarization orientation versus the grating grooves. The highest SMSR of the weak feedback mode is 54 dB at the injection current of 300 mA. The tunable range of the ECDL with weak feedback mode reaches 130.9 nm.

9.
Opt Express ; 27(16): A1225-A1240, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510516

RESUMO

We present the trend and seasonal variability of stratospheric NO2 column for the first time over the polluted atmosphere at Hefei, China, retrieved using Fourier transform infrared spectroscopy (FTIR) between 2015 and 2018. The FTIR observed stratospheric NO2 columns over Hefei show a peak in June and reach a minimum in January. The mean stratospheric NO2 column concentration in June is (3.49 ± 0.25) × 1015 molecules*cm-2, and is 39.20% ± 8.95% higher than that in January with a mean value of (2.51 ± 0.21) × 1015 molecules*cm-2. We find a negative trend of (-0.34 ± 0.05) %/yr in the FTIR observations of stratospheric NO2 column. The FTIR data are compared to the satellite OMI observations to assess the new data set quality and also applied to evaluate the GEOS-Chem model simulations. We find in general the OMI observations and GEOS-Chem model results are in good agreement with the coincident FTIR data, and they all show similar seasonal cycles with strong correlation coefficients of 0.84-0.86. The annual average OMI minus FTIR difference is (1.48 ± 5.33) × 1014 molecules*cm-2 (4.82% ± 17.37%), and average GEOS-Chem minus FTIR difference is (2.36 ± 2.33) × 1014 molecules*cm -2 (7.66% ± 7.49%). Their maximum differences occur in April and May with mean differences of 12-16%. We also found negative trends in the stratospheric NO2 column over Hefei for 2015-2018 with both OMI observations (-0.91 ± 0.09%/yr) and GEOS-Chem model results (-0.31 ± 0.05%/yr), demonstrating some consistency among them.

10.
J Periodontal Res ; 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31512745

RESUMO

BACKGROUND AND OBJECTIVE: Periodontitis is a multifactorial disease that can lead to the progressive destruction of dental support tissue. However, the detailed mechanisms and specific biomarkers involved in periodontitis remain to be further studied. Recently, long non-coding RNAs (lncRNAs) have been found to play a more important role than other types of RNAs. In our study, we analysed the expression of lncRNAs in periodontitis by analysing GSE16134. MATERIAL AND METHODS: We identified highly correlated genes by analysing GSE16134 with weighted gene co-expression network analysis (WGCNA) and identified 50 hub lncRNAs that were dysregulated. Then, we used the Linear Models for Microarray Data (Limma) package to identify the hub lncRNAs that were differentially expressed (DElncRNAs). The ceRNA co-expression network data were obtained from several sites, including miRcode, and were used to assess the potential WGCNA function of hub DElncRNAs in periodontitis. Besides, we divided the samples into LBX2-AS1 high and low expression group by the expression level of LBX2-AS1 and calculated DEG by Limma package. Furthermore, we performed GO function, KEGG pathway and GSEA enrichment of DEGs. RESULTS: In the analysis, we identified 50 hub lncRNAs that may play important roles in periodontitis. Then, we used the Limma package to identify 3 hub DElncRNAs (LINC00687, LBX2-AS1 and LINC01566). We elucidated the potential function of the hub DElncRNA LBX2-AS1 in periodontitis by constructing a co-expression network of lncRNA-miRNA-mRNA interactions. Totally, 573 DEGs (354 up- and 219 downregulated) in periodontitis samples were identified. DEGs were enriched in different GO terms and pathways, such as neutrophil degranulation, neutrophil activation, neutrophil activation involved in immune response, neutrophil-mediated immunity, antigen processing and presentation, JAK-STAT signalling pathway, natural killer cell-mediated cytotoxicity, EGFR tyrosine kinase inhibitor resistance, phosphatidylinositol signalling system and Vascular Endothelial Growth Factor (VEGF) signalling pathway. CONCLUSION: In our study, we found that 3 hub DElncRNAs (LINC00687, LBX2-AS1 and LINC01566) may be involved in the pathogenesis of periodontitis based on WGCNA and Limma analysis. Our study aimed to elucidate the mechanisms involved in periodontitis at the genetic and epigenetic levels by constructing a ceRNA network associated with lncRNA. Besides, identification DEGs of differential LBX2-AS1 and functional annotation showed that LBX2-AS1 might be associated with periodontitis.

11.
Bioresour Technol ; 293: 122021, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31514121

RESUMO

The intrinsic reason determining digestion performance of 100-160 °C preheated food waste after recovering floatable oil (FO-recovered FW) was investigated using two-dimensional correlated infrared spectroscopy, three-dimensional fluorescence spectroscopy and high-throughput 16S rRNA amplicon sequencing. The results indicated that thermal temperature significantly affected CH4 production of FO-recovered FW due to different structural alteration degree of starch, protein, cellulose and lipid components. Fragmentation of starch mainly occurred at 100 °C. The hydrolytic and acidogenic rate of starch was promoted and accordingly induced rapid growth of carbohydrate-fermenting bacteria, which resulted in severe acidification. Protein hydrolysis and cellulose H-bonds cleavage occurring at 120-160 °C accelerated the accessible sites interacting with microbial hydrolytic enzymes, and growth of Cloacimonetes and Syntrophomonas enhanced CH4 production. Non-degradable humic acid-like organics remarkably formed at 160 °C caused a carbon loss and digestion inhibiting/deteriorating. Pretreatment at 120 °C was feasible for promoted methane production based on energy assessment.


Assuntos
Alimentos , Metano , Anaerobiose , Reatores Biológicos , RNA Ribossômico 16S , Temperatura Ambiente
12.
Curr Biol ; 29(18): 3065-3071.e2, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31474534

RESUMO

To counter their widespread loss, global aspirations are for no net loss of remaining wetlands [1]. We examine whether this goal alone is sufficient for managing China's wetlands, for they constitute 10% of the world's total. Analyzing wetland changes between 2000 and 2015 using 30-m-resolution satellite images, we show that China's wetlands expanded by 27,614 km2 but lost 26,066 km2-a net increase of 1,548 km2 (or 0.4%). This net change hides considerable complexities in the types of wetlands created and destroyed. The area of open water surface increased by 9,110 km2, but natural wetlands-henceforth "marshes"-decreased by 7,562 km2. Of the expanded wetlands, restoration policies contributed 24.5% and dam construction contributed 20.8%. Climate change accounted for 23.6% but is likely to involve a transient increase due to melting glaciers. Of the lost wetlands, agricultural and urban expansion contributed 47.7% and 13.8%, respectively. The increase in wetlands from conservation efforts (6,765 km2) did not offset human-caused wetland losses (16,032 km2). The wetland changes may harm wildlife. The wetland loss in east China threatens bird migration across eastern Asia [2]. Open water from dam construction flooded the original habitats of threatened terrestrial species and affected aquatic species by fragmenting wetland habitats [3]. Thus, the "no net loss" target measures total changes without considering changes in composition and the corresponding ecological functions. It may result in "paper offsets" and should be used carefully as a target for wetland conservation.

13.
Zhongguo Gu Shang ; 32(8): 696-700, 2019 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-31533378

RESUMO

OBJECTIVE: To explore long-term outcomes of Chiari osteotomy for Legg-Calvé-Perthes disease in children with type Catterall III or IV, and to analyze clinical effect of osteotomy angle on clinical and radiographic results. METHODS: From March 2005 to July 2013, 26 children with Legg-Calvé-Perthes disease with type Catterall III or IV were treated by Chiari osteotomy, including 17 males and 9 females, aged from 4 to 13 years old with an average of (8.9±2.6) years old. Children were divided into low osteotomy angle group and high osteotomy angle group. according to osteotomy angle. There were 10 children in low osteotomy angle group with an osteotomy angle of 10 degrees, including 8 boys and 2 girls, aged from 4 to 13 years old with an average of (9.2±3.3) years old; while there were 16 children in high osteotomy angle group with an osteotomy angle of 15 degress, including 9 boys and 7 girls, aged from 6 to 12 years old with an average of (8.8±2.1) years old. HHS score before operation and at the latest follow-up were recorded to observe clinical results. CE angle of hip joint, acetabular index, Sharp angle, Shenton's line continuity, femoral head coverage, acetabular depth ratio were recorded to compare radiographic results. Stulberg classification was analyzed to compare reshaping ability of femoral head. RESULTS: Twenty-six children were followed up for 4.5 to 12.0 years with an average of (7.9±1.8) years. All incisions were healed at stage I for 10 to 14 days, with an average of(12.3±1.1) days. No inflammation, skin necrosis and injury of vessel and nerve occurred. All osteotomies achieved bone union for 8 to 13 weeks, with an average of(9.8±1.4) weeks. HHS score increased from 75.8±6.5 before operation to 93.5±2.5 at the latest follow-up in low osteotomy angle group(P<0.05), and form 77.6±6.2 to 97.8±1.6 in high osteotomy angle group (P<0.05). HHS score of high osteotomy angle group at the latest follow-up was higher than that of low osteotomy angle group (P<0.05). The acetabular index decreased from (10.1±2.5)° before operation to (4.5±1.3)° at the latest follow-up in low osteotomy angle group (P<0.05), and from (10.7±3.3)° before operation to (2.0±1.1)° in high osteotomy angle group (P<0.05). The acetabular index of high osteotomy angle group at the latest followup was better than low osteotomy angle group(P<0.05). There was no significant difference in CE angle, Sharp angle, Shenton's continuity, femoral head coverage, acetabular depth ratio between two groups. According to Stulberg classification, the femoral head reshaping ability in high osteotomy angle group was better than that of low osteotomy angle group(P<0.05). CONCLUSIONS: Chiari osteotomy with 15° for Legg-Calvé-Perthes disease in children with type Catterall III or IV could effectively decrease index of acetabulum, and helpful for femoral head reshaping ability, then in further improve clinical effects.


Assuntos
Cabeça do Fêmur , Osteotomia , Acetábulo , Adolescente , Criança , Pré-Escolar , Feminino , Articulação do Quadril , Humanos , Inflamação , Masculino , Resultado do Tratamento
14.
BMC Musculoskelet Disord ; 20(1): 361, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391055

RESUMO

BACKGROUND: Extramedullary systems are commonly used in knee arthroplasty, with the rod location being determined from the tibial torsion line during surgery. The traditional method for tibial torsion measurement is not in accordance with clinical practice. This study aimed to evaluate proximal and distal tibial torsion using 3-dimensional (3D) computed technology to establish a new evaluation method, as well as to investigate the association between tibial torsion and postoperative alignment deviation. METHODS: Fifty-five osteoarthritis tibias with >10°varus preoperatively were divided into valgus, neutral, and varus groups based on their postoperative alignment deviation. A new method based on clinical practice was built using a 3D tibial model. Proximal and distal tibial torsions were measured by both the new and traditional methods. In addition, tibial osteotomy that followed the intramedullary osteotomy system was simulated on the 3D model in the varus and valgus groups to investigate the association between tibial torsion and alignment deviation. RESULTS: Proximal tibial torsion was smaller and distal torsion was greater in the valgus group than the other two groups, according to the new method (p = 0.03 and p = 0.02, respectively). No significant difference was found when comparing these torsions by the traditional method (p = 0.782 and p = 0.753, respectively). In the valgus group, the postoperative alignment deviation improved after simulated osteotomy guided by the intramedullary system, while no significant improvement was found in the varus group. CONCLUSION: According to this new tibial-rotation evaluation method, valgus deviation in knee arthroplasty was identified as the main cause for knees in which the proximal tibial internal torsion is too small and the distal external torsion is too great. The use of an intramedullary system may help reduce this deviation. TRIAL REGISTRATION: Prospectively registered.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31434162

RESUMO

Chronic bacterial infections in the oral cavity influence the development of dental caries. Mutans streptococci (MS) is the major pathogenic cause of dental caries. The World Health Organization (WHO) ranks dental caries, cancer and cardiovascular diseases as the three major global diseases that need urgent preventative and curative measures. However, substantial evidence suggests that traditional prevention and treatment strategies are inefficient in reducing the prevalence of dental caries. For protection against caries, it is important to develop effective vaccines that induce anti-colonizing immunity against Streptococcus mutans infections. In the present investigation, we constructed a fusion anti-caries DNA vaccine (PAcA-ctxB) through fusing A region of cell surface protein PAc (PAcA) coding gene of Mutans streptococci with cholera toxin B subunit coding gene (CTB). Afterwards, the plasmids were integrated into tomato genomes through agrobacterium-mediated plant transformation technology. The presence of transgenes in the tomato genome was confirmed by PCR, GUS and western blot. The expression of genes was confirmed at transcription and protein level. Altogether, the results presented herein showed that transgenic tomatoes may provide a useful system for the production of human caries antigen. This article is protected by copyright. All rights reserved.

16.
Sci Rep ; 9(1): 11509, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395937

RESUMO

Contemporary medical imaging is becoming increasingly more quantitative. The emerging field of radiomics is a leading example. By translating unstructured data (i.e., images) into structured data (i.e., imaging features), radiomics can potentially characterize clinically useful imaging phenotypes. In this paper, an exploratory radiomics approach is used to investigate the potential association between quantitative imaging features and pulmonary function in CT images. Thirty-nine radiomic features were extracted from the lungs of 64 patients as potential imaging biomarkers for pulmonary function. Collectively, these features capture the morphology of the lungs, as well as intensity variations, fine-texture, and coarse-texture of the pulmonary tissue. The extracted lung radiomics data was compared to conventional pulmonary function tests. In general, patients with larger lungs of homogeneous, low attenuating pulmonary tissue (as measured via radiomics) were found to be associated with poor spirometry performance and a lower diffusing capacity for carbon monoxide. Unsupervised dynamic data clustering revealed subsets of patients with similar lung radiomic patterns that were found to be associated with similar forced expiratory volume in one second (FEV1) measurements. This implies that patients with similar radiomic feature vectors also presented with comparable spirometry performance, and were separable by varying degrees of pulmonary function as measured by imaging.

17.
J Photochem Photobiol B ; 197: 111551, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31306954

RESUMO

Heavy metal pollution as one of the most serious pollution problems of marine environment, seriously threatens the safety of marine organism and human health, and will lead to potential risks for the marine ecological environment. In order to develop a rapid and sensitive toxicity detection method for marine heavy metals, in this study, marine diatom Nitzschia closterium was used as the test organism, and the effects of different concentrations of lead (Pb) on the five chlorophyll fluorescence parameters of N. closterium including the maximum photochemical quantum yield of PSII (Fv/Fm), the effective quantum yield of PSII photochemical energy conversion (ΦPSII), the effective absorption cross section of PSII photochemistry (σPSII'), the relative electron transfer rate of PSII (rP), and the PSII electron flux per unit volume (JVPII) at different exposure times were investigated based on chlorophyll fluorescence technology. By comparing with the photosynthetic activity fluorescence parameter Fv/Fm which is commonly used for toxicity analysis of pollutants using algae as test organisms, the optimal chlorophyll fluorescence parameter that could rapidly and sensitively determine Pb toxicity to N. closterium was selected. The results indicate that all the five chlorophyll fluorescence parameters of Fv/Fm, ΦPSII, σPSII', rP and JVPII showed good dose-response relationships with Pb within 8 h exposure time, and they all could be used as endpoints to rapidly determine Pb toxicity to N. closterium. Among the five chlorophyll fluorescence parameters, JVPII was the most sensitive fluorescence parameter for detecting the toxicity of Pb to N. closterium within 6 h exposure. And for JVPII, the median effective concentration (EC50) values of Pb at 2, 4 and 6 h were 0.329, 0.068 and 0.040 mmol L-1, respectively. However, when the exposure time was 8 h, ΦPSII was the most sensitive fluorescence parameter for the toxicity detection of Pb, and the EC50 value of Pb at 8 h was 0.038 mmol L-1. This study will provide an important basis for the development of a rapid and sensitive detection method for the biological toxicity of marine heavy metals, and those results will be helpful for ecological risk assessment in marine environment.


Assuntos
Clorofila/química , Chumbo/toxicidade , Microalgas/efeitos dos fármacos , Microalgas/química , Microalgas/metabolismo , Complexo de Proteína do Fotossistema II/química , Complexo de Proteína do Fotossistema II/metabolismo , Teoria Quântica , Espectrometria de Fluorescência , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
18.
Global Health ; 15(1): 43, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262312

RESUMO

BACKGROUND: Non-communicable diseases (NCDs)-chronic human health problems such as cardiovascular diseases linked to poor diets-are significant challenges for sustainable development and human health. The international livestock trade increases accessibility to cheap animal products that may expand diet-related NCDs worldwide. However, it is not well understood how the complex interconnections among livestock production, trade, and consumption affect NCD risks around the world. METHOD: Our global dataset included 33 livestock products (meat, offal, and animal fats) in 156 countries from 1992 to 2011. We employed path analysis to uncover how livestock trade contributes to diet-related NCDs and identify underlying environmental and socioeconomic factors of livestock trade. Then we performed trend analyses to investigate long-term changes in livestock production and trade at a country level. RESULTS: We found that livestock consumption through livestock import increased diet-related NCD risks. This was especially true in developing countries, which in general were not well prepared in terms of policies for NCD risk reduction, and where there was a lack of funding to implement the policies. Population size and income level were the main factors affecting global livestock import activities. CONCLUSIONS: Our results suggest that new governance structures to incorporate separate international efforts, improved national policies, and bolstering individual efforts are needed to decrease NCD risks, particularly in developing countries.


Assuntos
Comércio , Internacionalidade , Gado , Doenças não Transmissíveis/epidemiologia , Animais , Doenças Cardiovasculares/epidemiologia , Países em Desenvolvimento , Dieta/efeitos adversos , Humanos , Fatores Socioeconômicos
19.
Sci Total Environ ; 689: 434-443, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31279190

RESUMO

How leaf traits vary with environmental and climatic variables in cold and arid environments is an essential issue in environmental ecology. Here, we analyzed the variations in leaf nitrogen (N) and phosphorus (P) stoichiometry and leaf dry matter content (LDMC) in Qilian juniper (Juniperus przewalskii Kom.) growing in 14 environmentally different plots on the northeastern Tibetan Plateau. The results showed that the N and P concentrations, N:P ratio and LDMC of Qilian juniper were 10.89 mg.g-1, 1.04 mg.g-1, 10.80 and 483.06 mg.g-1, respectively. The spatial coefficients of the variations in leaf N and P stoichiometry were significantly higher than the seasonal ones, and the correlations of leaf N and P concentrations with spatial variables were stronger than their correlations with the season. During the growing season, only the leaf N concentration and N:P ratio significantly increased. Soil nutrients were highly positively significantly correlated with leaf P concentrations but negatively correlated with the N:P ratio and LDMC. However, leaf N concentrations showed no significant correlations with soil nutrients. We suggest that the effects of temperature on the N concentration and LDMC were stronger than the effects of drought, while those on the P concentration and N:P ratio were weaker. Drought reduced leaf N and P concentrations and increased the N:P ratio and LDMC. In the arid region, with an increasing mean annual temperature (MAT), leaf N concentration significantly decreased, and LDMC significantly increased. In the semi-arid region, as MAT increased, leaf N and P concentrations significantly increased and LDMC and the N:P ratio significantly decreased. These opposite results supported the growth rate hypothesis that plant N and P concentrations increase while the N:P ratio and LDMC decrease as the growth rate increases.

20.
Trends Ecol Evol ; 34(9): 762-766, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301875

RESUMO

We discuss institutional reforms to China's protected area management. Currently (as elsewhere), protected areas suffer fragmented management, lack of a comprehensive classification, inadequate coverage of biodiversity and ecosystem services, and divided, inconsistent legislation. We recommend establishing a new system of protected area management that can address past difficulties by using ongoing institutional reforms as unprecedented opportunities.

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