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1.
Food Chem ; 340: 128164, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33011470

RESUMO

The internal blue discoloration of radish root after harvest is a physiological phenomenon that decreases the radish quality. Internal blue discoloration in the roots of 16 varieties of Chinese radish along with the stability of blue pigment under different light, pH, and temperature conditions were investigated. Among the varieties LB05-244 and LB05-240 displayed the greatest degrees of discoloration, while the Piton and Dense radishes exhibited the lowest degrees of discoloration. The light and pH conditions along with the storage temperature affected the pigment stability. The degradation of blue pigment occurred faster under blue light than under green, red, and white light and darkness. Blue pigment degraded fastest at pH values of 13 and 1. The blue pigments in radish exhibited thermal instability, with complete degradation occurring in 5 or 10 min at 90 or 100 °C, respectively. In conclusion, variety affected the discoloration. The pigment exhibited light, pH and thermal instability.

2.
Sci Rep ; 10(1): 19394, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33173087

RESUMO

Hand, foot and mouth disease (HFMD) is a growing threat to children's health, causing a serious public health burden in China. The relationships between associated meteorological factors and HFMD have been widely studied. However, the HFMD burden due to relative humidity from the perspective of attributable risk has been neglected. This study investigated the humidity-HFMD relationship in three comprehensive perspectives, humidity-HFMD relationship curves, effect modification and attributable risks in the Sichuan Basin between 2011 and 2017. We used multistage analyses composed of distributed lag nonlinear models (DLNMs), a multivariate meta-regression model and the calculations of attributable risk to quantify the humidity-HFMD association. We observed a J-shaped pattern for the pooled cumulative humidity-HFMD relationship, which presented significant heterogeneity relating to the geographical region and number of primary school students. Overall, 27.77% (95% CI 25.24-30.02%) of HFMD infections were attributed to humidity. High relative humidity resulted in the greatest burden of HFMD infections. The proportion of high humidity-related HFMD in the southern basin was higher than that in the northern basin. The findings provide evidence from multiple perspectives for public health policy formulation and health resource allocation to develop priorities and targeted policies to ease the HFMD burden associated with humidity.

3.
Otolaryngol Head Neck Surg ; : 194599820963129, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33167757

RESUMO

OBJECTIVE: To evaluate a treatment strategy for internal carotid artery blowout syndrome caused by nasopharyngeal carcinoma. STUDY DESIGN: A retrospective analysis of a case series was performed. SETTING: Carotid blowout syndrome is a catastrophic complication caused by malignant tumor of the skull base. METHODS: A retrospective analysis based on 69 patients with internal carotid artery blowout syndrome admitted to our center between April 2018 and January 2020 was performed. The patients were divided into 2 groups: an EBBA (internal carotid artery embolization + bypass based on American Society of Intervention and Therapeutic Neuroradiology/Society of Interventional Radiology [ASITN/SIR]) group and an embolization/stent group. The follow-up time was 6 to 9 months. RESULTS: In the EBBA group, 41 patients (41/49, 83.7%) survived. Forty patients had a satisfactory quality of life after 3 months. No death occurred within 3 months. Nonoperative death occurred in 8 cases (8/49, 16.3%). The rate of mortality and disability was 18.4% (9/49). In the embolization/stent group, 16 patients (16/20, 80%) survived. Nonoperative death occurred in 4 cases (4/20, 20%), 3 of which occurred within 1 to 3 months. Four cases reported Modified Rankin Scale ≥2 after 3 months. The rate of mortality and disability was 40% (8/20). CONCLUSION: A comprehensive revascularization strategy for internal carotid artery (ICA) embolization and intracranial and extracranial bypass grafting based on ASITN/SIR score for ICA blowout syndrome patients not only can prolong the patient survival but also greatly improve the survival probability and quality of life as well as reduce their rate of mortality or disability.

4.
Langmuir ; 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33170711

RESUMO

The trivalent europium ion (Eu3+) has garnered a great deal of interest for the design of luminescent materials possessing compound-independent emission bands, strong luminescent intensity, and long emission lifetimes. We herein introduce a synthetic methodology capable of constructing visual luminescent probes from Eu3+ complex-functionalized silica nanocomposites and their Langmuir-Blodgett (LB) films at interfaces. In order to facilitate the coordinative stabilization of Eu3+ over carrier surfaces, silica nanoparticles (nanoSiO2) were pregrafted with terpyridyl (TPy) to make nanoSiO2TPy linkers. Then, a well-designed coordination reaction of nanoSiO2TPy with EuCl3 and 2,6-pyridinedicarboxylic acid (DPA) was carried out at solid-liquid and air-water interfaces, where our desired material (denoted as nanoSiO2TPy@EuDPA) and its corresponding LB film are obtained. The presence of TPy and DPA interacting with Eu3+ plays a key role in regulating the chemical nature of the particle surface, hence giving rise to closely packed nanocomposite arrays in the film. As a result, the improvement in uniformity and stability is achieved alongside the enhancement in emission intensity and lifetime. With such advantageous optical properties, we find them workable as facile, green, and affordable luminescent sensors, by which a range of common toxic anions (Cr2O72-, MnO4-, and PO43-) can be visually and quantitatively recognized. Notably, the LB film-based material could afford a higher Ksv value (1.53 × 105 M-1), a lower detection limit (0.157 µM), and better recyclability than its original powder analogue, showcasing its utility as a more promising candidate for practical use.

5.
J Atheroscler Thromb ; 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33191314

RESUMO

AIM: The triglyceride-glucose index (TyG index) is proposed as a surrogate parameter for insulin resistance (IR) and, when elevated, is related to increased cardiovascular risks. Whether the TyG index is of great value in predicting adverse prognosis for individuals diagnosed with non-ST-segment elevation acute coronary syndrome (NSTE-ACS), who received elective percutaneous coronary intervention (PCI), and without recognized diabetes remains unclear. METHODS: Overall, 1,510 subjects diagnosed with NSTE-ACS, who received elective PCI, and without recognized diabetes were enrolled in the current study. All participants received a routine follow-up after discharge. The TyG index was obtained from the following equation: napierian logarithmic (ln) [fasting triglyceride (TG, mg/dL)×fasting blood glucose (FBG, mg/dL)/2]. Adverse cardiovascular events included all-cause death, nonfatal myocardial infarction (MI), nonfatal ischemic stroke, and ischemia-driven revascularization, composite of which was defined as the primary endpoint. RESULTS: Overall, 316 (20.9%) endpoint events were documented during a 48-month follow-up. Despite adjusting for confounding variates, the TyG index remains to be a significant risk predictor for the primary endpoint, with a hazard ratio (HR) [95% confidence interval (CI)] of 2.433 (1.853-3.196) (P<0.001). A significant enhancement on the predictive performance for the primary endpoint emerged when adding the TyG index into a baseline model [area under the receiver-operating characteristic (ROC) curve (AUC), 0.835 for baseline model vs. 0.853 for baseline model+TyG index, P<0.001; net reclassification improvement (NRI), 0.194, P<0.001; integrated discrimination improvement (IDI), 0.023, P=0.007]. CONCLUSIONS: The TyG index is an independent risk predictor for adverse cardiovascular events in nondiabetic subjects diagnosed with NSTE-ACS and who received elective PCI. Further prospective studies are needed to verify these findings.

6.
ACS Appl Mater Interfaces ; 12(45): 51057-51068, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33138373

RESUMO

An intrinsically hydrophilic nanofibrous membrane with chlorine rechargeable biocidal and antifouling functions was prepared by using a combination of chemically bonded N-halamine moieties and zwitterionic polymers (PEI-S). The designed nanofibrous membrane, named as PEI-S@BNF-2 h, can exhibit integrated features of reduced bacterial adhesion, rechargeable biocidal activity, and easy release of killed bacteria by using mild hydrodynamic forces. The representative functional performances of the PEI-S@BNF-2 h membrane include high active chlorine capacity (>4000 ppm), large specific surface area, ease of chlorine rechargeability, long-term stability, and exceptional biocidal activity (99.9999% via contact killing). More importantly, the zwitterionic polymer moieties (PEI-S) brought robust antifouling properties to this biocidal membrane, therefore reducing the biofouling-biofilm effect and prolonging the lifetime of the filtration membrane. These attributes enable the PEI-S@BNF-2 h nanofibrous membrane to effectively disinfect the microbe-contaminated water with high fluxes (10,000 L m-2 h-1) and maintain itself clean for a long-term application.

7.
Plant Sci ; 300: 110641, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33180701

RESUMO

Virus-derived small interfering RNAs (vsiRNAs) can target not only viruses but also plant genes. Apple chlorotic leaf spot virus (ACLSV) is an RNA virus that infects Rosaceae plants extensively, including apple, pear and hawthorn. Here, we report an ACLSV-derived vsiRNA [vsiR1360(-)] that targets and down-regulates the leucine-rich repeat receptor-like kinase 1 (LRR-RLK1) gene of hawthorn (Crataegus pinnatifida). The targeting and cleavage of the CpLRR-RLK1 gene by vsiR1360(-) were validated by RNA ligase-mediated 5' rapid amplification of cDNA ends and tobacco transient transformation assays. And the CpLRR-RLK1 protein fused to green fluorescent protein localized to the cell membrane. Conserved domain and phylogenetic tree analyses showed that CpLRR-RLK1 is closely related to the proteins of the LRRII-RLK subfamily. The biological function of CpLRR-RLK1 was explored by heterologous overexpression of CpLRR-RLK1 gene in Arabidopsis. The results of inoculation of Pst DC3000 in Arabidopsis leaves showed that the symptoms of CpLRR-RLK1 overexpression plants infected with Pst DC3000 were significantly reduced compared with the wild type. In addition, the detection of reactive oxygen species and callose deposition and the expression analysis of defense-related genes showed that the CpLRR-RLK1 gene can indeed enhance the resistance of Arabidopsis to bacteria disease.

8.
Oxid Med Cell Longev ; 2020: 6352876, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33123313

RESUMO

N-methyl-N´-nitro-N-nitrosoguanidine is a clear carcinogen, increasing evidence that indicates an etiological role of human papillomavirus in esophageal carcinoma. Studies have reported the synergistic effect on environmental carcinogens and viruses in recent years. On the basis of establishing the malignant transformation model of Het-1A cells induced by synergistic of HPV18 and MNNG, this study was to explore the synergistic carcinogenesis of MNNG and HPV. Our research indicated that HPV&MNNG led to a significant increase in the protein-expression levels of c-Myc, cyclinD1, BCL-2, BAX, E-cadherin, N-cadherin, mTOR, LC3II, and p62, with concomitant decreases in p21 and LC3I. HPV18 and MNNG induced accumulation of p62 and its interaction with KEAP1, which promoted NRF2 nuclear translocation. p62 loss prevents growth and increases autophagy of malignant cells by activating KEAP1/NRF2-dependent antioxidative response. In addition, PI3K and p-AKT were stimulated by HPV&MNNG, and PI3K/AKT/mTOR is positively associated with cell proliferation, migration, invasion, and autophagy during malignant transformation. Taken together, MNNG&HPV regulates autophagy and further accelerates cell appreciation by activating the p62/KEAP1/NRF2 and PI3K/AKT/mTOR pathway. MNNG&HPV may improve Het-1A cell autophagy to contribute to excessive cell proliferation, reduced apoptosis, and protection from oxidative damage, thus accelerating the process of cell malignant transformation and leading to cancerous cells.

9.
Br J Ophthalmol ; 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33127829

RESUMO

PURPOSE: To describe changes in the prevalence of visual impairment and glasses ownership with age and as associated with income and population density for visual impairment among rural and urban migrant Chinese students. DESIGN: Meta-analysis of 12 cross-sectional, school-based studies conducted between 2012 and 2017. SETTING: Rural and urban migrant schools in seven Chinese provinces. PARTICIPANTS: A total of 83 273 rural and urban migrant Chinese students aged 6-17 years. RESULTS: Prevalence of visual impairment (uncorrected visual acuity ≤6/12 in either eye) rose from 19.0% at age 6 to 66.9% at 17, with the overall age-adjusted prevalence higher for girls (35.8%) than for boys (30.1%, p<0.001). The rate of glasses ownership among students who needed them increased from 13.0% at age 6 to 63.9% (p<0.001) at 17 and was significantly higher for girls (37.0%) than boys (34.7%, p<0.001). The unmet need for glasses as a proportion of the student population peaked in junior high school (31.8%). A 1% increase in per capita gross domestic product was associated with a 4.45% rise in uncorrected visual acuity (R2=0.057, p=0.020). Population density was significantly associated with glasses ownership among children (R2=0.359, p=0.012). A 1% population density increase was associated with an increase in the glasses ownership rate of 6.83%. CONCLUSION: Efforts are needed to improve vision screening coverage in China's schools, particularly junior high schools, as this is when many rural children leave school and glasses coverage is lowest.

10.
BMJ Open Ophthalmol ; 5(1): e000572, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083554

RESUMO

Objective: To assess the effect of free eyeglasses provision on visual acuity among middle school students in northwestern rural China. Methods and analysis: Among 31 middle schools randomly selected from 47 middle schools in northwestern rural China, students were randomly allocated by school to one of two interventions: free eyeglasses (intervention group), and eyeglasses prescriptions given only to the parents (control group). The main outcome of this study is uncorrected visual acuity after 9 months, adjusted for baseline visual acuity. Results: Among 2095 students from 31 middle schools, 995 (47.5%) failed the visual acuity screening, 515 (51.8%, 15 schools) of which were randomly assigned to the intervention group, with the remaining 480 students (48.2%, 16 schools) assigned to the control group. Among these, a total of 910 students were followed up and analysed. Endline eyeglasses wear in the intervention group was 44%, and 36% in the control group. Endline visual acuity of students in the intervention group was significantly better than students in the control group, adjusting for other variables (0.045 LogMAR units, 95% CI 0.006 to 0.084, equivalent to 0.45 lines, p=0.027), and insignificantly better only for baseline visual acuity (difference of 0.008 LogMAR units, 95% CI -0.018 to 0.034, equivalent to 0.08 lines). Conclusion: We found no evidence that receiving free eyeglasses worsened visual acuity among middle school students in northwestern rural China. Trial registration number: ISRCTN17141957.

11.
Cell Biol Int ; 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33085139

RESUMO

Circulating tumor cells (CTCs) indicate the diagnosis and prognosis of cancer patients, together with benefiting individual treatment and anticancer drug development. However, moving forward for large-scale application in general population still requires systematically multifaceted modifications for currently proprietary new technologies based on filtration. We primitively utilized a cell size-based platform to evaluate the recovery efficiency of spiked abnormal cell lines and analyzed circulating abnormal cells (CACs). To dissect the subpopulations of CACs, we conducted immunofluorescent (IF) staining with a combination of unique biomarkers of CTCs and circulating endothelial cells (CECs). Furthermore, we improved the CTC screening system by assessing the feasibility of transferring CTCs for automatic IF analysis, together with simulating and optimizing the circumstances for long-term CTC storage and transportation. We detected CACs in 15 HD candidates with CTC characteristics such as abnormally large cytomorphology, high nucleo-cytoplasmic ratio and positive for panCK or VIM staining. Thereafter, we improved accuracy of the platform by distinguishing CTCs from CECs, which satisfied the elementary requirement for small-scale CTC screening in HD candidates. Finally, large-scale CTC screening in general population was available after multifaceted modifications including automatic analysis by transferring CTCs onto slides, choosing appropriate blood-collecting tube, optimizing the conditions for long-term CTC storage and transportation and evaluating the potential effect on CTC phenotype. Hence, we systematically modified the scope of technique parameters, improved the accuracy of early cancer detection and made it realizable for large-scale CTC or CEC screening in general population. This article is protected by copyright. All rights reserved.

12.
ACS Appl Mater Interfaces ; 12(44): 50126-50134, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33090773

RESUMO

Despite small-molecule surfactants and polymers being widely used as pesticide adjuvants to inhibit droplet bouncing and splashing, they still have intrinsic drawbacks either in the easy wind drift and evaporation, the unfavorable wettability, or the usage of nonrenewable resources. In this paper, we found that upon droplet impacting, 1D nanofibers assembled from natural glycyrrhizic acid (GL) could pin on the rough hydrophobic surface and delay the retraction rate of droplets effectively. Using GL as a tank-mixed adjuvant, the efficiency of glyphosate to control the weed growth was improved significantly in the field experiment, which addressed the dilemmas of current adjuvants elegantly. Our work not only provides a constructive way to overcome droplet bouncing but also prompted us to verify in future if all 1D nanofibers assembled from different small molecules can display similar control efficiencies.

13.
Arthritis Rheumatol ; 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33124780

RESUMO

OBJECTIVES: The changes of gut microbiota have been linked with systemic lupus erythematosus, but knowledge is limited. Our study aimed to provide an in-depth understanding of the contribution of gut microbiota to the immunopathogenesis of SLE. METHODS: The fecal metagenomes from 117 non-treated SLE patients and 52 SLE patients post-treatment aligned with 115 matched healthy controls were analyzed by whole-genome profiling. For comparison, we assessed the fecal metagenome of MRL/lpr mice. The oral microbiota-origin of the gut species that existed in SLE patients was documented by SNP-based strain-level analyses. Functional validation assays were performed to demonstrate the molecular mimicry of newly-found microbial peptides. RESULTS: The gut microbiota of SLE display significant differences in microbial composition and function compared with healthy controls. Certain species, including Clostridium sp. ATCC BAA-442, Atopobium rimae,Shuttleworthia satelles,Actinomyces massiliensis,Bacteroides fragilis, and Clostridium leptum were enriched in SLE gut and reduced after treatment. Enhanced lipopolysaccharide biosynthesis aligned with reduced branched-chain amino acid biosynthesis was observed in the SLE gut. The findings from mice are consistent with our findings from patients. Interestingly, some species with an oral microbiota-origin were enriched in the gut of SLE patients. Functional validation assays demonstrated the pro-inflammatory capacities of some microbial peptides derived from SLE-enriched species. CONCLUSIONS: Our study provides detailed information on the microbiota of non-treated patients with SLE, including their functional signatures, similarities with murine counterparts, oral origin, and the definition of autoantigen-mimicking peptides. Our data argue that microbiome altering approaches may offer valuable adjuvant therapies.

14.
Chem Commun (Camb) ; 56(85): 12905-12908, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33030187

RESUMO

Macrocyclic hexaoxazoles (6OTDs) are G-quadruplex (G4) ligands, and some derivatives, such as L2H2-6OTD (1a) bearing two aminobutyl side chains, show cytotoxicity towards cancer cells. To identify the cellular target of 1a, we employed a post-target-binding strategy utilizing click reaction (Huisgen cyclization) between the azide-conjugated ligand L2H2-6OTD-Az (1b) and the cell-permeable dye CO-1 bearing a strained alkyne moiety and the BODIPY fluorophore under Cu-free conditions. We confirmed that introduction of the small azide group did not alter the physical or biological properties, including anti-cancer activity, of 1a, and we also demonstrated bias-free localization of CO-1. The post-binding visualization strategy suggested that L2H2-6OTD (1a) colocalized with RNA G4 in living cells.

15.
Biomed Pharmacother ; 132: 110833, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33035831

RESUMO

Chronic kidney disease (CKD) is one of the most common conditions which significantly increases the risk for serious health outcomes. Epidemiological investigations have shown that CKD has become a serious global health problem. At present, there are no treatments for CKD, thus the need for an effective and safe treatment for this condition. Shenkang Injection (SKI), which is an herbal medication in Chinese Medicine, has been used in the management and treatment of CKD and has achieved favorable therapeutic effects. The purpose of this paper is to review the clinical efficacy, mechanism of action, and safety profile of SKI when used in CKD, and to provide comprehensive potential evidence for its clinical application.

16.
BMC Public Health ; 20(1): 1528, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33036602

RESUMO

BACKGROUND: Numerous studies have demonstrated the potential association between rainfall and hand, foot and mouth disease (HFMD), but the results are inconsistent. This study aimed to quantify the relationship between rainfall and HFMD based on a multicity study and explore the potential sources of spatial heterogeneity. METHODS: We retrieved the daily counts of childhood HFMD and the meteorological variables of the 143 cities in mainland China between 2009 and 2014. A common time series regression model was applied to quantify the association between rainfall and HFMD for each of the 143 cities. Then, we adopted the meta-regression model to pool the city-specific estimates and explore the sources of heterogeneity by incorporating city-specific characteristics. RESULTS: The overall pooled estimation suggested a nonlinear exposure-response relationship between rainfall and HFMD. Once rainfall exceeded 15 mm, the HFMD risk stopped increasing linearly and began to plateau with the excessive risk ratio (ERR) peaking at 21 mm of rainfall (ERR = 3.46, 95% CI: 2.05, 4.88). We also found significant heterogeneity in the rainfall-HFMD relationships (I2 = 52.75%, P < 0.001). By incorporating the city-specific characteristics into the meta-regression model, temperature and student density can explain a substantial proportion of spatial heterogeneity with I2 statistics that decreased by 5.29 and 6.80% at most, respectively. CONCLUSIONS: Our findings verified the nonlinear association between rainfall and HFMD. The rainfall-HFMD relationship also varies depending on locations. Therefore, the estimation of the rain-HFMD relationship of one location should not be generalized to another location.

17.
Eur Radiol ; 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009590

RESUMO

OBJECTIVES: To investigate the association of contrast-enhanced cone beam breast CT (CE-CBBCT) features, immunohistochemical (IHC) receptors, and molecular subtypes in breast cancer. METHODS: In this retrospective study, patients who underwent preoperative CE-CBBCT and received complete IHC results were analyzed. CE-CBBCT features were evaluated by two radiologists. Observer reproducibility and feature reliability were assessed. The association between CE-CBBCT features, IHC receptors, and molecular subtypes was analyzed using the chi-square, Mann-Whitney, and Kruskal-Wallis tests. Multivariate logistic regression was performed to assess the ability of combined imaging features to discriminate molecular subtypes. ROC curve was used to evaluate prediction performance. RESULTS: A total of 240 invasive cancers identified in 211 women were enrolled. Molecular subtypes of breast cancer were significantly associated with focality number of lesions, lesion type, tumor size, lesion density, internal enhancement pattern, degree of lesion enhancement (ΔHU), mass shape, spiculation, calcifications, calcification distribution, and increased peripheral vascularity of lesion (all p < 0.005), some of which also helped to differentiate IHC receptor status. A multivariate logistic regression model showed that tumor size (odds ratio, OR = 1.244), mass shape (OR = 0.311), spiculation (OR = 0.159), and internal enhancement pattern (OR = 0.227) were associated with differentiation between luminal and non-luminal subtypes (AUC = 0.809). Combined CE-CBBCT features, including lesion type (OR = 0.118), calcifications (OR = 0.181), and ΔHU (OR = 0.962), could be significant indicators of triple-negative versus HER-2-enriched subtypes (AUC = 0.913). CONCLUSIONS: CE-CBBCT features have the potential to help predict IHC receptor status and distinguish molecular subtypes of breast cancer, which could in turn help to develop individual treatment decisions and prognosis predictions. KEY POINTS: • A total of 11 CE-CBBCT features were associated with molecular subtypes, some of which also helped to differentiate IHC receptor status. • Tumor size, irregular mass shape, spiculation, and internal enhancement pattern could help identify luminal subtype. • Lesion type, calcification, and ΔHU could be significant indicators of HER-2- enriched versus triple-negative breast cancers.

18.
Ann Bot ; 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33035305

RESUMO

BACKGROUND AND AIMS: Theory predicts that outcrossing should be more prevalent among perennials than annuals, a pattern confirmed by comparative evidence from diverse angiosperm families. However, intraspecific comparisons between annual and perennial populations are few because such variation is uncommon among flowering plants. Here, we test the hypothesis that perennial populations outcross more than annual populations by investigating Incarvillea sinensis, a wide-ranging insect-pollinated herb native to China. The occurrence of both allopatric and sympatric populations allow us to examine the stability of mating system differences between life histories under varying ecological conditions. METHODS: We estimated outcrossing rates and biparental inbreeding in 16 allopatric and five sympatric populations in which both life histories co-existed using 20 microsatellite loci. In each population we measured height, branch number, corolla size, tube length and herkogamy for ~30 individuals. In a sympatric population, we recorded daily flower number, pollinator visitation and the fruit and seed set of annual and perennial plants. KEY RESULTS: As predicted, outcrossing rates (t) were considerably higher in perennial (mean = 0.76) than annual (mean = 0.09) populations. This difference in mating system was also maintained at sympatric sites where plants grew intermixed. In both allopatric and sympatric populations the degree of herkogamy was consistently larger in outcrossing than selfing plants. Perennials were more branched, with more and larger flowers than in annuals. In a sympatric population, annuals had a significantly higher fruit and seed set than perennials. CONCLUSIONS: Genetically-based differences in herkogamy between annuals and perennials appear to play a key role in governing outcrossing rates in populations, regardless of variation in local ecological conditions. The maintenance of mating system and life-history trait differentiation between perennial and annual populations of I. sinensis probably results from correlated evolution in response to local environmental conditions.

19.
Sensors (Basel) ; 20(20)2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33080892

RESUMO

For high-precision measurements of the CO2 column concentration in the atmosphere with airborne integrated path differential absorption (IPDA) Lidar, the exact distance of the Lidar beam to the scattering surface, that is, the length of the column, must be measured accurately. For the high-precision inversion of the column length, we propose a set of methods on the basis of the actual conditions, including autocorrelation detection, adaptive filtering, Gaussian decomposition, and optimized Levenberg-Marquardt fitting based on the generalized Gaussian distribution. Then, based on the information of a pair of laser pulses, we use the direct adjustment method of unequal precision to eliminate the error in the distance measurement. Further, the effect of atmospheric delay on distance measurements is considered, leading to further correction of the inversion results. At last, an airborne experiment was carried out in a sea area near Qinhuangdao, China on March 14, 2019. The results showed that the ranging accuracy can reach 0.9066 m, which achieved an excellent ranging accuracy on 1.57-µm IPDA Lidar and met the requirement for high-precision CO2 column length inversion.

20.
J Int Neuropsychol Soc ; : 1-14, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33012297

RESUMO

OBJECTIVE: This study investigated the latent factor structure of the NIH Toolbox Cognition Battery (NIHTB-CB) and its measurement invariance across clinical diagnosis and key demographic variables including sex, race/ethnicity, age, and education for a typical Alzheimer's disease (AD) research sample. METHOD: The NIHTB-CB iPad English version, consisting of 7 tests, was administered to 411 participants aged 45-94 with clinical diagnosis of cognitively unimpaired, dementia, mild cognitive impairment (MCI), or impaired not MCI. The factor structure of the whole sample was first examined with exploratory factor analysis (EFA) and further refined using confirmatory factor analysis (CFA). Two groups were classified for each variable (diagnosis or demographic factors). The confirmed factor model was next tested for each group with CFA. If the factor structure was the same between the groups, measurement invariance was then tested using a hierarchical series of nested two-group CFA models. RESULTS: A two-factor model capturing fluid cognition (executive function, processing speed, and memory) versus crystalized cognition (language) fit well for the whole sample and each group except for those with age < 65. This model generally had measurement invariance across sex, race/ethnicity, and education, and partial invariance across diagnosis. For individuals with age < 65, the language factor remained intact while the fluid cognition was separated into two factors: (1) executive function/processing speed and (2) memory. CONCLUSIONS: The findings mostly supported the utility of the battery in AD research, yet revealed challenges in measuring memory for AD participants and longitudinal change in fluid cognition.

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