Assessing limb apraxia after ischemic stroke: validation of the Chinese version of the diagnostic instrument for limb apraxia-short version (DILA-S) classic subtests.

OBJECTIVE: This study aimed to translate and validate the Chinese version of the Diagnostic Instrument for Limb Apraxia-Short Version (DILA-S) classic subtests in Chinese patients after ischemic stroke. METHODS: The DILA-S was translated and adapted for use in Mandarin-speaking Chinese patients. Internal consistency, test-retest reliability, dimensionality, convergent validity, divergent validity, and concurrent validity were tested. RESULTS: A total of 112 ischemic stroke patients were included. The internal consistency (Cronbach's alpha 0.85 ~ 0.92) and test-retest reliability (ICC 0.88 ~ 0.93) were found satisfactory. Exploratory factor analysis obtained two factors for the imitation subtests and the execution scale of the pantomime of tool use. Convergent validity was supported by strong correlations (ρ > 0.7) between the scores of the DILA-S subtests and the LOTCA motor praxis subscale. Divergent validity was acceptable for weak to moderate correlations (ρ ranged from -0.25~ -0.41) between the scores of the DILA-S subtests and the NIHSS. Concurrent validity was supported by strong correlations (ρ > 0.7) between the scores of the DILA-S subtests and the MoCA, as well as strong correlations (ρ > 0.6 < 0.7) between the scores of the DILA-S subtests and the BI. CONCLUSION: The Chinese version of the DILA-S classic subtests demonstrated satisfactory psychometric properties for assessing limb apraxia in Chinese patients after ischemic stroke.

Climatic Warming-Induced Drought Stress Has Resulted in the Transition of Tree Growth Sensitivity from Temperature to Precipitation in the Loess Plateau of China.

Ongoing climate warming poses significant threats to forest ecosystems, particularly in drylands. Here, we assess the intricate responses of tree growth to climate change across two warming phases (1910-1940 and 1970-2000) of the 20th century in the Loess Plateau of China. To achieve this, we analyzed a dataset encompassing 53 ring-width chronologies extracted from 13 diverse tree species, enabling us to discern and characterize the prevailing trends in tree growth over these warming phases. The difference in the primary contributors over two warming phases was compared to investigate the association of tree growth with climatic drivers. We found that the first warming phase exerted a stimulating effect on tree growth, with climate warming correlating to heightened growth rates. However, a contrasting pattern emerged in the second phase as accelerated drought conditions emerged as a predominant limiting factor, dampening tree growth rates. The response of tree growth to climate changed markedly during the two warming phases. Initially, temperature assumed a dominant role in driving the tree growth of growth season during the first warming phase. Instead, precipitation and drought stress became the main factors affecting tree growth in the second phase. This drought stress manifested predominantly during the early and late growing seasons. Our findings confirm the discernible transition of warming-induced tree growth in water-limited regions and highlight the vulnerability of dryland forests to the escalating dual challenges of heightened warming and drying. If the warming trend continues unabated in the Loess Plateau, further deterioration in tree growth and heightened mortality rates are foreseeable outcomes. Some adaptive forest managements should be encouraged to sustain the integrity and resilience of these vital ecosystems in the Loess Plateau and similar regions.

Calculation of evapotranspiration in different climatic zones combining the long-term monitoring data with bootstrap method.

Evapotranspiration (ET) is a central process in the climate system that plays a crucial role in the regional water cycle and climate regulation. However, estimating the effects of regional ET on the regional water cycle and climate regulation remains challenging due to the lack of quantitative methods and large-scale direct observational data. This study develops a new method to estimate evapotranspiration at regional scales using long-term monitoring data and the bootstrap resampling approach to calculate the ET unit area per year for China. This study applies the deviance information criterion as a goodness-of-fit index to select the most optimal formula for estimating regional ET for different climatic zones in China. The bootstrap resampling method was used to estimate parameter distribution in different climatic zones based on the outcome of 2000 trials. The results show that the predicted ET of adjacent climates overlaps with each other. The subtropical monsoonal climatic zone had the widest range of predicted ET (0-8000 mm/year), followed by the temperate and monsoonal climatic zones (0-1500 mm/year), mountain plateau climatic zone (0-1000 mm/year), and temperate continental climatic zone (0-500 mm/year). The probability distributions and isopleths of regionally predicted ET were also determined for China. The methods used in this study provide a promising tool to assess the effects of introducing large-scale forestation or restoration of trees on local water resources management.

Plant traits in influencing soil moisture in semiarid grasslands of the Loess Plateau, China.

Large-scale vegetation restoration projects pose threats to water resource security in water-limited regions. Thus, the quantification of how vegetation cover affects soil moisture is of key importance to support effective restoration schemes in drylands. However, the current understanding of such effects remains poor. For this study, an in-situ vegetation-removal experiment was conducted at 36 herbaceous grassland sites having different community compositions and topographical conditions in two adjacent loess watersheds of the Loess Plateau, China. The effects of vegetation cover (vegetation effects) on soil moisture were analyzed across soil profiles (0-180 cm) and two growing seasons. Overall, 13 plant traits and 7 topographic and soil properties were employed to evaluate how community compositions modulated vegetation effects on soil moisture. The results showed that vegetation cover increased soil moisture in the surface layer (0-20 cm) by 6.81% during wet periods (semi-monthly rainfall >30 mm) relative to an in-situ unvegetated control, but primarily induced a decline of soil moisture in the deep soil layer (20-180 cm) by 19.44% across two growing seasons. Redundancy analysis (RDA) and structural equation modeling (SEM) suggested that these vegetation effects on soil moisture were significantly correlated with vegetative height, leaf area, shallow root allocation, and slope gradient. Our study revealed that tall, small-leaved, and shallow-rooted plants on flat topographies were beneficial to soil water retention and replenishment. This implied that current restoration strategies may be significantly improved through the development of optimal communities and diverse terracing measures. Our findings are anticipated to provide effective guidance for soil water conservation, as well as ecosystem rehabilitation in dry and degraded regions.

Diversity and population structure of a dominant deciduous tree based on morphological and genetic data.

Knowledge of the genetic diversity and structure of tree species across their geographic ranges is essential for sustainable use and management of forest ecosystems. Acer grosseri Pax., an economically and ecologically important maple species, is mainly distributed in North China. In this study, the genetic diversity and population differentiation of 24 natural populations of this species were evaluated using sequence-related amplified polymorphism markers and morphological characters. The results show that highly significant differences occurred in 32 morphological traits. The coefficient of variation of 34 characters was 18.19 %. Principal component analysis indicated that 18 of 34 traits explained 60.20 % of the total variance. The phenotypic differentiation coefficient (VST) was 36.06 % for all morphological traits. The Shannon-Wiener index of 34 morphological characters was 6.09, while at the population level, it was 1.77. The percentage of polymorphic bands of all studied A. grosseri populations was 82.14 %. Nei's gene diversity (He) and Shannon's information index (I) were 0.35 and 0.50, respectively. Less genetic differentiation was detected among the natural populations (GST = 0.20, ΦST = 0.10). Twenty-four populations of A. grosseri formed two main clusters, which is consistent with morphological cluster analysis. Principal coordinates analysis and STRUCTURE analysis supported the UPGMA-cluster dendrogram. There was no significant correlation between genetic and geographical distances among populations. Both molecular and morphological data suggested that A. grosseri is rich in genetic diversity. The high level of genetic variation within populations could be affected by the biological characters, mating system and lifespan of A. grosseri, whereas the lower genetic diversity among populations could be caused by effective gene exchange, selective pressure from environmental heterogeneity and the species' geographical range.

Facile and sensitive detection of protamine by enhanced room-temperature phosphorescence of Mn-doped ZnS quantum dots.

Quantum dot (QD) nanohybrids provide an effective route to explore the new properties of materials and are increasingly used as highly valuable sensitive (bio) chemical probes. Interestingly, the room-temperature phosphorescence (RTP) of 3-mercaptopropionic acid (MPA)-capped Mn-doped ZnS QDs could be remarkably enhanced by the addition of protamine. Based on the above finding, a simple, sensitive, and selective method for rapid detection of protamine was successfully designed. With this method, protamine as a cationic peptide interacts electrostatically with MPA-capped Mn-doped ZnS QDs to form MPA-capped Mn-doped ZnS QD/protamine complexes, which leads to the aggregation of QDs and enhances the RTP intensity. Under the optimized conditions, the RTP intensity change was linearly proportional to the concentration of protamine in the range 0.2-3.0 µg ml(-1), and the limit of detection was 0.14 µg ml(-1). The proposed method was successfully applied to detect protamine in protamine sulfate injection and human serum samples with satisfactory results, and the recovery ranged from 96.5 to 105.6%.

Selective room temperature phosphorescence detection of heparin based on manganese-doped zinc sulfide quantum dots/polybrene self-assembled nanosensor.

A selective system was developed to detect heparin in aqueous solutions by using MPA(3-Mercaptopropionic Acid)-capped Mn-doped ZnS quantum dots (QDs)/polybrene (hexadimethrine bromide) hybrids as a sensitive room temperature phosphorescence (RTP) nanosensor. In this system, the RTP intensity of QDs was remarkably enhanced via electrostatic self-assembly after the addition of polybrene. The addition of heparin into the system was competitively bound to polybrene and enable to deprive it from the surface of QDs, as a result, the RTP intensity of Mn-doped ZnS QDs/polybrene hybrids was reduced with the increased of heparin concentration. Based on this effect, a selective system was proposed to detect heparin. Under the optimal conditions, the change of RTP intensity was proportional to the heparin concentration from 0.05 to 1.4 U mL(-1) (about 0.38-10.76 µg mL(-1)) and the limit of detection (LOD) was 0.021 U mL(-1) (about 0.16 µg mL(-1)). This proposed nanosensor is simple and relatively free of interference from coexisting substances, which can be applied to detect heparin in heparin injection and human serum. In addition, a new pathway was also provided based on the assembly of QDs with other cationic homopolymers for further design of biosensors and detection of biomolecules.

Self-assembly of manganese doped zinc sulfide quantum dots/CTAB nanohybrids for detection of rutin.

Quantum dots (QDs) nanohybrids are an effective route to obtain new property of materials, and are very significant for developing specific materials and improving the performance of existing QDs materials. The objectives of this work are to prepare MPA-capped Mn-doped ZnS QDs/CTAB nanohybrids (MPA: 3-mercaptopropionic acid; CTAB: cetyltrimethyl ammonium bromide) through electrostatic self-assembly, to investigate the formation mechanism and the Room-Temperature Phosphorescenee (RTP) changes, and to explore the possibility of their application in detection of rutin. As a result, MPA-capped Mn-doped ZnS QDs/CTAB nanohybrids greatly improve the rutin detection ability of QDs and provide an important method for developing more convenient and effective rutin detection sensor. The sensor for rutin gave a detection limit of 0.037 mg L(-1) and two linear ranges from 0.05 to 0.5 mg L(-1) and from 0.5 to 5 mg L(-1), and thus can be expanded to selective detection of other substances. Since the present QDs-based RTP method does not need deoxidants or other inducers as conventional RTP detection methods, and avoids interference from autofluorescence and the scattering light of the matrix that are encountered in spectrofluorometry, this method can be used to detect the content of rutin in body fluid.