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1.
Water Res ; 266: 122360, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39236504

RESUMO

Freeze-thaw (FT) events profoundly perturb the biochemical processes of soil and water in mid- and high-latitude regions, especially the riparian zones that are often recognized as the hotspots of soil-water interactions and thus one of the most sensitive ecosystems to future climate change. However, it remains largely unknown how the heterogeneously composed and progressively discharged meltwater affect the biochemical cycling of the neighbor soil. In this study, stream water from a valley in the Chinese Loess Plateau was frozen at -10°C for 12 hours, and the meltwater (at +10°C) progressively discharged at three stages (T1 ∼ T3) was respectively added to rewet the soil collected from the same stream bed (Soil+T1 ∼ Soil+T3). Our results show that: (1) Approximately 65% of the total dissolved organic carbon and 53% of the total NO3--N were preferentially discharged at the first stage T1, with enrichment ratios of 1.60 ∼ 1.94. (2) The dissolved organic matter discharged at T1 was noticeably more biodegradable with significantly lower SUVA254 but higher HIX, and also predominated with humic-like, dissolved microbial metabolite-like, and fulvic acid-like components. (3) After added to the soil, the meltwater discharged at T1 (e.g., Soil+T1) significantly accelerated the mineralization of soil organic carbon with 2.4 ∼ 8.07-folded k factor after fitted into the first-order kinetics equation, triggering 125 ∼ 152% more total CO2 emissions. Adding T1 also promoted significantly more accumulation of soil microbial biomass carbon after 15 days of incubation, especially on the FT soil. Overall, the preferential discharge of the nutrient-enriched meltwater with more biodegradable DOM components at the initial melting stage significantly promoted the microbial growth and respiratory activities in the recipient soil, and triggered sizable CO2 emission pulses. This reveals a common but long-ignored phenomenon in cold riparian zones, where progressive freeze-thaw can partition and thus shift the DOM compositions in stream water over melting time, and in turn profoundly perturb the biochemical cycles of the neighbor soil body.


Assuntos
Congelamento , Solo , Solo/química , Água/química , Compostos Orgânicos , Carbono , Rios/química
2.
Sci Total Environ ; 934: 173287, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38776786

RESUMO

Microbial metabolism is closely related to soil carbon dioxide emissions, which in turn is related to environmental issues such as global warming. Dissolved organic matter (DOM) affects many fundamental biogeochemical processes such as microbial metabolism involved in soil carbon cycle, not only directly by its availability, but also indirectly by its chemodiversity. However, the association between the DOM chemodiversity and bioavailability remains unclear. To address this knowledge gap, soils from two agro-ecological experimental sites subjected to various long-term fertilizations in subtropical area was collected. The chemodiversity of DOM was detected by multi-spectroscopic techniques including ultraviolet-visible spectrophotometry, Fourier transform infrared spectroscopy and excitation emission matrices fluorescence spectroscopy. Results showed that long-term manure amendments significantly decreased microbial metabolic quotient (qCO2) by up to 57%. We also observed that long-term manure amendments significantly increased recalcitrant components of DOM (indicated by the aromaticity, humification index, the ratio of aromatic carbon to aliphatic carbon, and the relative abundances of humic-like components) and decreased labile components of DOM. Negatively correlation between the qCO2 and the proportion of recalcitrant components of DOM supported that accumulation in recalcitrant components of DOM increased microbial carbon utilization efficiency. Random forest models also showed the highest contribution of the relative abundances of humic-like components and the aromaticity of DOM in affecting qCO2. Both of the redundancy analysis and structural equation modeling further indicated the decisive role of soil pH in influencing the DOM chemodiversity. Soil pH explained 56.7% of the variation in the chemodiversity of DOM. The accumulation of recalcitrant components in DOM with increasing soil pH might be attributed to the accelerated microbial consumption of bioavailability components and/or to the negative impact on the solubility of bioavailability components. Overall, this research highlights the significance of long-term manure amendments in regulating qCO2 by altering the chemodiversity of soil DOM.


Assuntos
Esterco , Microbiologia do Solo , Solo , Solo/química , Fertilizantes , Substâncias Húmicas , Agricultura/métodos , Ciclo do Carbono , Monitoramento Ambiental
3.
Psicothema ; 36(1): 1-14, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38227295

RESUMO

BACKGROUND: Applying a three-level meta-analysis, the goal of our investigation was to examine the relationship between parental homework involvement and students' achievement, and to investigate whether certain study features could have resulted in the inconsistent results relating to this relationship from prior studies. METHOD: We identified a total of 28 studies (32 independent samples) with 252 effect sizes for a total of 378222 participants. RESULTS: Our meta-analysis revealed an overall weak negative relationship between parental homework involvement and students' achievement ( r = −0.064, p < 0.001). The overall relationship was moderated by the dimension of parental homework involvement. Specifically, students' achievement was positively related to autonomy support, but largely unrelated to content support, parental control, frequency, and mixed. Additionally, the overall relationship was moderated by achievement measure, grade level, and parent gender. CONCLUSIONS: Given that parental autonomy support was the only dimension that was positively related to students' achievement, it would be important to conduct qualitative research that provides longitudinal descriptions of parent-child interactions relating to homework tasks as children make their transition from elementary to middle and high school.


Assuntos
Sucesso Acadêmico , Humanos , Instituições Acadêmicas , Relações Pais-Filho , Pais , Estudantes
4.
Environ Pollut ; 340(Pt 2): 122784, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37871740

RESUMO

Plastic mulching films and phosphate fertilizers have been widely used to improve agricultural soil productivity. Microplastics (MP) and phosphorus (P) significantly accumulate in agricultural soil and water bodies. However, the effects of residual MP on P availability in soil and aqueous mediums remain unclear. In this study, available P (Olsen-P) in soils and P adsorption capacity in aqueous medium were determined to examine the influence of MP properties on P availability in laboratory. In agricultural soils, Olsen-P was significantly affected by MP types. Conventional MP (mulching film particles), such as polyethylene (PE) and polyvinyl chloride (PVC), and biodegradable MP, such as polylactic acid (PLA), substantially reduced soil Olsen-P by 9.7-38.6% and 38.4-73.6%, respectively. The size and concentration of MP strongly affected soil Olsen-P, with smaller (25 µm) and more concentrated (5%) MP causing greater reductions in Olsen-P. In the soil contaminated with MP, increased fulvic acid content significantly increased Olsen-P levels. Microplastics exhibited strong P adsorption capacities, leading to decreased P availability in aqueous medium. Conventional MP exhibited a higher P adsorption capacity than biodegradable MP, with P distribution coefficients (Kd values) ordered as PVC (5.19 L kg-1) > PE (4.23 L kg-1) > PLA (2.48 L kg-1). Notably, the Kd values increased with decreasing sizes of conventional MP, whereas the opposite trend was observed for PLA. The presence of fulvic acid affected the adsorption of P by MP in aqueous medium. Increased fulvic acid content reduced P adsorption capacity of MP, thus enhancing P availability. Our findings contribute to a better understanding of P dynamics in MP-contaminated agricultural soil and aqueous medium, which could aid in formulating sustainable agricultural practices and effective environmental management strategies for plastic mulching films and P contamination.


Assuntos
Plásticos , Solo , Fósforo , Microplásticos , Matéria Orgânica Dissolvida , Água , Poliésteres
5.
EFORT Open Rev ; 8(11): 841-853, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37909700

RESUMO

Purpose: To determine whether using robots in spine surgery results in more clinical advantages and fewer adverse consequences. Methods: Between October 1990 and October 2022, a computer-based search was conducted through the databases of PubMed, Cochrane Library, Embase, Web of Science, China National Knowledge Infrastructure, China Biology Medicine, VIP databases, and WAN FANG. The study only included randomized controlled trials (RCTs) comparing the clinical efficacy and safety of robot-assisted surgery with those of conventional spine surgery. The review was conducted following PRISMA 2020, and AMSTAR-2 was used to evaluate the methodological quality. R version 4.2.1 was used in the meta-analysis. The Cochrane Collaboration Tool was used for evaluating the risk of bias. Results: This study analyzed 954 participants from 20 RCTs involving cervical spondylosis, lumbar degenerative disease, scoliosis, etc. The robot-assisted group outperformed the freehand group in terms of intraoperative blood loss, number of screws in grade A position, grade A + B position, radiation dose, and hospital stay. Operation duration, visual analog scale scores of low back pain, Oswestry disability index, and radiation exposure time did not significantly differ between the two groups. Conclusions: Although robotic spine surgery is more accurate in pedicle screw placement than conventional methods, the robot group did not demonstrate an advantage in terms of clinical efficacy. Studies of complications and cost-effectiveness are still very rare.

6.
Materials (Basel) ; 16(20)2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37895678

RESUMO

Numerous technological advancements in the 21st century depend on the creation of novel materials possessing enhanced properties; there is a growing reliance on materials that can be optimized to serve multiple functions. To efficiently save time and meet the requirements of diverse applications, high-throughput and combinatorial approaches are increasingly employed to explore and design superior materials. Among them, gradient thin-film deposition is one of the most mature and widely used technologies for high-throughput preparation of material libraries. This review summarizes recent progress in gradient thin-film deposition fabricated by magnetron sputtering, multi-arc ion plating, e-beam evaporation, additive manufacturing, and chemical bath deposition, providing readers with a fundamental understanding of this research field. First, high-throughput synthesis methods for gradient thin films are emphasized. Subsequently, we present the characteristics of combinatorial films, including microstructure, oxidation, corrosion tests, and mechanical properties. Next, the screening methods employed for evaluating these properties are discussed. Furthermore, we delve into the limitations of high-throughput preparation and characterization techniques for combinatorial films. Finally, we provide a summary and offer our perspectives.

7.
Sci Total Environ ; 895: 165192, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37385503

RESUMO

The timing and magnitude of greenhouse gas (GHG) production depend strongly on soil oxygen (O2) availability, and the soil pore geometry characteristics largely regulate O2 and moisture conditions relating to GHG biochemical processes. However, the interactions between O2 dynamics and the concentration and flux of GHGs during the soil moisture transitions under various soil pore conditions have not yet been clarified. In this study, a soil-column experiment was conducted under wetting-drying phases using three pore-structure treatments, FINE, MEDIUM, and COARSE, with 0 %, 30 %, and 50 % coarse quartz sand applied to soil, respectively. The concentrations of soil gases (O2, nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4)) were monitored at a depth of 15 cm hourly, and their surface fluxes were measured daily. Soil porosity, pore size distribution, and pore connectivity were quantified using X-ray computed microtomography. The soil O2 concentrations were found to decline sharply as soil moisture increased to the water holding capacities of 0.46, 0.41, and 0.32 cm cm-3 in the FINE, MEDIUM, and COARSE, respectively. The dynamic patterns of the O2 concentrations varied across the soil pore structures, decreasing to anaerobic in FINE (<0.01 %) and MEDIUM (0.02 %), and to hypoxic (4.42 %) in COARSE. Correspondingly, the soil N2O concentration was the highest in FINE (101 µL L-1) and the lowest in COARSE (10 µL L-1), whereas the highest surface N2O flux was observed in MEDIUM (131 µg N m-2 h-1). As soil CO2 concentrations declined, CO2 fluxes increased from FINE to MEDIUM to COARSE. Most pores of FINE, MEDIUM, and COARSE were 15-80 µm, 85-100 µm, and 105-125 µm, respectively, in terms of diameter. The X-ray CT visible (>15 µm) porosity in FINE, MEDIUM and COARSE were 0.09, 0.17, and 0.28 mm3 mm-3, respectively. The corresponding Euler-Poincaré numbers were 180,280, 76,705, and -10,604, respectively, indicating higher connectivity in COARSE than in MEDIUM or FINE. In soil dominated by small air-filled porosity which limits gas diffusion and result in low soil O2 concentration, N2O concentration was increased and CO2 flux was inhibited as the moisture content increased. The turning point in the sharp decrease in O2 concentration was found to correspond with a moisture content, and a pore diameter of 95-110 µm was associated with the critical turning point between holding water and O2 depletion in soil. These findings suggest that O2-regulated biochemical processes are key to the production and flux of GHGs, which in turn are dependent on the soil pore structure and a coupling relationship between N2O and CO2. Improved understanding of the intense effect of soil physical properties provided an empirical foundation for the future development of mechanistic prediction models for how pore-space scale processes with high temporal (hourly) resolution up to GHGs fluxes at larger spatial and temporal scales.

8.
Proc Natl Acad Sci U S A ; 120(21): e2208276120, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37186859

RESUMO

Iron-chalcogenide superconductors FeSe1-xSx possess unique electronic properties such as nonmagnetic nematic order and its quantum critical point. The nature of superconductivity with such nematicity is important for understanding the mechanism of unconventional superconductivity. A recent theory suggested the possible emergence of a fundamentally new class of superconductivity with the so-called Bogoliubov Fermi surfaces (BFSs) in this system. However, such an ultranodal pair state requires broken time-reversal symmetry (TRS) in the superconducting state, which has not been observed experimentally. Here, we report muon spin relaxation (µSR) measurements in FeSe1-xSx superconductors for 0 ≤ x ≤ 0.22 covering both orthorhombic (nematic) and tetragonal phases. We find that the zero-field muon relaxation rate is enhanced below the superconducting transition temperature Tc for all compositions, indicating that the superconducting state breaks TRS both in the nematic and tetragonal phases. Moreover, the transverse-field µSR measurements reveal that the superfluid density shows an unexpected and substantial reduction in the tetragonal phase (x > 0.17). This implies that a significant fraction of electrons remain unpaired in the zero-temperature limit, which cannot be explained by the known unconventional superconducting states with point or line nodes. The TRS breaking and the suppressed superfluid density in the tetragonal phase, together with the reported enhanced zero-energy excitations, are consistent with the ultranodal pair state with BFSs. The present results reveal two different superconducting states with broken TRS separated by the nematic critical point in FeSe1-xSx, which calls for the theory of microscopic origins that account for the relation between nematicity and superconductivity.

9.
Front Neurol ; 13: 948828, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36188404

RESUMO

Background and objective: Diffusion-weighted imaging (DWI) hyperintensities were occasionally seen at previous hematoma in patients several months after intracerebral hemorrhage with surgery. Whether they are newly occurred clinical situations or post-surgery changes is unknown. This study aims to investigate the prevalence and possible mechanisms for this phenomenon. Methods: We retrospectively reviewed the MRI database for intracerebral hemorrhage with surgery after 3 months of disease onset in our hospital. We also prospectively performed repeated multimodal MRI scans for two patients at the chronic stage after surgery for intracerebral hemorrhage. Results: We found that 14 out of 23 patients (60.9%) had DWI hyperintensities at the site of previous hematoma 3 months after intracerebral hemorrhage with surgery. All the DWI lesions were hyperintense on T1- and T2-weighted imaging, most of which appeared long and narrow in shape. The DWI lesions were usually located adjacent to the thin wall of the previous hematoma cavity close to the lateral ventricle. They were more associated with the basal ganglia hemorrhage than with the lobar hemorrhage (P = 0.02) and were more frequently seen for those with intraventricular hemorrhage than without (P = 0.02). Prospectively repeated MRI exams of two patients revealed unchanged DWI hyperintensity during the 18- and 2-month follow-up, respectively. Conclusion: The DWI lesions at previous hematoma were commonly seen in patients after surgery for intracerebral hemorrhage at the chronic stage which would persist for years. We hypothesized a possible mechanism by which extracellular methemoglobin "islands" are formed with delayed or no absorption by macrophages from adjacent thin residual brain tissue. Unnecessary further examinations and treatment would be avoided by realizing this imaging phenomenon.

10.
Huan Jing Ke Xue ; 43(9): 4748-4755, 2022 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-36096615

RESUMO

As an emerging pollutant to the environment, microplastics have received widespread attention worldwide. The Loess Plateau, as one of the major agricultural production areas in China, has various land use types, but how the abundance and morphological patterns of microplastics differ among soils under different land use types remains unclear. In this study, we collected soils from three different land use types:croplands, apple orchards, and landfills in the Wangdonggou Catchment. Microplastics were separated and extracted using a modified density centrifugation method, and the abundance, composition, and morphological characteristics of the soil were analyzed and characterized using a laser infrared imaging system. The results showed that the average abundance of microplastics in the Wangdonggou Catchment was 4715 n·kg-1, mainly composed of PET, PU, and alkyd varnish(ALK), respectively accounting for 30.39%, 29.58%, and 8.42%. More than 80% of the microplastics were fragmented, and more than 60% of the microplastics were of a size ≤ 50 µm. The average abundance of microplastics varied significantly among land use types:cropland soil (7550 n·kg-1)>apple orchard soil (3440 n·kg-1)>landfill soil (2283 n·kg-1). The average area, width, height, eccentricity, circularity, and other morphological characteristics of microplastics in apple orchard soil were significantly different from those in the cropland and landfill soil.


Assuntos
Microplásticos , Plásticos , Agricultura/métodos , China , Solo
11.
Front Psychol ; 13: 923882, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36033015

RESUMO

During the past several decades, the previous studies have been focusing on the related theoretical issues and measuring tool of homework behaviors (mainly including homework time, completion, and homework creativity). However, the effects of these homework behaviors on general creativity remain unknown. Employing a number of questionnaires, this study investigated two samples from middle schools of Mainland China. The results showed that (1) the eight-item version of Homework Creativity Behaviors Scale had acceptable validity and reliability; (2) compared with homework completion and homework time, homework creativity explained less variety of academic achievement (3.7% for homework creativity; 5.4% for completion and time); (3) homework creativity explained more variance of general creativity than that of homework completion and homework time accounted (7.0% for homework creativity; 1.3% for completion and time); and (4) homework creativity was negatively associated with grade level. Contrary to the popular beliefs, homework completion and homework creativity have positive effects on the students' general creativity. Several issues that need further studies were also discussed.

12.
J Immunol Res ; 2022: 5799776, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35607406

RESUMO

Glioma is a serious fatal type of cancer with the shorter median survival period and poor quality of living. The overall 5-year survival rate remains low due to high recurrence rates. Glioma stem cells (GSCs) play the important roles in the development of gliomas. Examination of the numerous biomarkers or cancer-associated genes involved in the development or prevention of glioma may therefore serve the discovery of novel strategies to treat patients with glioma. Hypoxia induced by using CoCl2 application and 14-3-3ß protein knockdown by specific small interfering RNA transfection were performed in GSCs both in vitro and in vivo to observe their role in glioma progression and metastasis occurrence by using western blot analysis and MTT assay. The results demonstrated that CoCl2 application enhanced the 14-3-3ß protein expression and mRNA levels via the PI3K pathway in GSCs. Furthermore, hypoxia promoted GSC cell proliferation and activated the expression of proliferating cell nuclear antigen, which was inhibited following 14-3-3ß knockdown. In addition, tumor growth in mice was enhanced by CoCl2 application but reversed following 14-3-3ß knockdown, which also enhanced GSC cell apoptosis. In conclusion, the present study demonstrated that hypoxia promoted glioma growth both in vitro and in vivo by increasing the 14-3-3ß expression via the PI3K signaling pathway. 14-3-3ß and HIF-1α may therefore be considered as the potential therapeutic target to treat patients with glioma.


Assuntos
Neoplasias Encefálicas , Glioma , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Animais , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Proliferação de Células , Glioma/metabolismo , Humanos , Hipóxia/metabolismo , Camundongos , Células-Tronco Neoplásicas/metabolismo
13.
Materials (Basel) ; 15(3)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35160967

RESUMO

The deformation behavior of the as-extruded Mg-Li-Al-Zn-Si alloy was studied by conducting a hot compression test, with a temperature range of 180-330 °C and a strain rate range of 0.01-10 s-1. The constitutive relationship of flow stress, temperature, and strain rate was expressed by the Zener-Hollomon parameter and included the Arrhenius term. By considering the effect of strain on the material constants, the flow stress at 240-330 °C could be precisely predicted with the constitutive equation (incorporating the influence of strain). A processing map was established at the strain of 0.7. The unsafe domains that are characterized by uneven microstructures were detected at low temperatures (<230 °C) or high temperatures (>280 °C), with high strain rates (>1 s-1). The optimum hot deformation region was obtained at a medium temperature (270-300 °C), with a peak power dissipation efficiency of 0.44. The microstructural evolution in different domains is investigated. The unstable domains are characterized by a non-uniform flow behavior and uneven microstructure. The observation showed that the dynamic recrystallization (DRX) process could easily occur at the safe domain with high power dissipation efficiency. For the α-phase, some features of continuous dynamic recrystallization can be found. The triple points serve as prominent nucleation sites for the ß-phase DRX grains and the growth in the grains was carried out by subgrain boundary migration. The microstructure exhibits characteristics of discontinuous dynamic recrystallization.

14.
ACS Omega ; 6(50): 34989-35001, 2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-34963980

RESUMO

The adiabatic spontaneous combustion period of coal is an important index for the macroscopic characterization of coal spontaneous combustion, and it is affected by many internal and external factors. There are several methods to study it, but there are various shortcomings to these methods. Some require too much time, while others have too many interfering factors. To quickly obtain the accurate adiabatic spontaneous combustion period of coal, a rapid contrastive experimental method was designed. In this method, the coal samples of the experimental and control groups were the same, and air and nitrogen were used as control atmospheres. A theoretical calculation method for the adiabatic spontaneous combustion period based on this method is proposed. The experimental results showed that during the temperature-programmed coal spontaneous combustion experiment, the increase in the coal temperature was due to physical and chemical heating. Physical heating is the heating effect of the temperature-programmed furnace body and the heated gas on the coal sample. Chemical heating includes oxidative exothermic heating promoted by physical and adiabatic oxidation heating. The adiabatic oxidative heat release can be determined by the oxidation heat release in the air atmosphere minus the oxidation heat release corresponding to the coal sample temperature in the nitrogen environment at the same period. The adiabatic spontaneous combustion period of coal can be calculated from the adiabatic oxidation heat release. Our results provide a rapid contrastive experimental method to quickly obtain the accurate adiabatic spontaneous combustion period of coal.

15.
ACS Omega ; 6(30): 19409-19418, 2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34368528

RESUMO

Significant volume shrinkage and drying cracking of high-water-content lignite will occur during low-temperature drying. To determine the variation behaviors of the drying shrinkage rate and desiccation crack surface width in the process of low-temperature drying, low-temperature and low-humidity drying experiments were conducted, and the variations of the surface widths of the desiccation crack with time and water content of old lignite were examined. The results showed that the slow drying of lignite at low temperatures caused significant volume shrinkage and desiccation crack formation, and the occurrence and development of desiccation cracks were highly nonuniform. Three stages of the variation of surface widths of the desiccation cracks were observed with the water content decrease: an initial rapid increase stage, a second slow decrease stage, and a final stable stage, and the average width of the desiccation cracks increased in a Gaussian function. The higher the evaporation rate and volume drying shrinkage rate, the lower the surface width of the desiccation cracks under low-temperature drying conditions. To achieve safe and green mining, storage, transportation, processing, and utilization of lignite, the moisture content of old lignite should be controlled to be above 13-15%.

16.
Front Surg ; 8: 765784, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071311

RESUMO

Background: We performed a meta-analysis to evaluate the effect of hypertonic saline compared to mannitol for the management of elevated intracranial pressure in traumatic brain injury. Methods: A systematic literature search up to July 2021 was performed and 17 studies included 1,392 subjects with traumatic brain injury at the start of the study; 708 of them were administered hypertonic saline and 684 were given mannitol. They were reporting relationships between the effects of hypertonic saline compared to mannitol for the management of elevated intracranial pressure in traumatic brain injury. We calculated the odds ratio (OR) and mean difference (MD) with 95% confidence intervals (CIs) to assess the effect of hypertonic saline compared to mannitol for the management of elevated intracranial pressure in traumatic brain injury using the dichotomous or continuous method with a random or fixed-effect model. Results: Hypertonic saline had significantly lower treatment failure (OR, 0.38; 95% CI, 0.15-0.98, p = 0.04), lower intracranial pressure 30-60 mins after infusion termination (MD, -1.12; 95% CI, -2.11 to -0.12, p = 0.03), and higher cerebral perfusion pressure 30-60 mins after infusion termination (MD, 5.25; 95% CI, 3.59-6.91, p < 0.001) compared to mannitol in subjects with traumatic brain injury. However, hypertonic saline had no significant effect on favorable outcome (OR, 1.61; 95% CI, 1.01-2.58, p = 0.05), mortality (OR, 0.59; 95% CI, 0.34-1.02, p = 0.06), intracranial pressure 90-120 mins after infusion termination (MD, -0.90; 95% CI, -3.21-1.41, p = 0.45), cerebral perfusion pressure 90-120 mins after infusion termination (MD, 4.28; 95% CI, -0.16-8.72, p = 0.06), and duration of elevated intracranial pressure per day (MD, 2.20; 95% CI, -5.44-1.05, p = 0.18) compared to mannitol in subjects with traumatic brain injury. Conclusions: Hypertonic saline had significantly lower treatment failure, lower intracranial pressure 30-60 mins after infusion termination, and higher cerebral perfusion pressure 30-60 mins after infusion termination compared to mannitol in subjects with traumatic brain injury. However, hypertonic saline had no significant effect on the favorable outcome, mortality, intracranial pressure 90-120 mins after infusion termination, cerebral perfusion pressure 90-120 mins after infusion termination, and duration of elevated intracranial pressure per day compared to mannitol in subjects with traumatic brain injury. Further studies are required to validate these findings.

17.
Sci Total Environ ; 755(Pt 2): 142616, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33045603

RESUMO

Despite the pivotal functional roles dominating the pace of nutrient cycles in terrestrial ecosystems, soil fungal communities at erosional and depositional sites have not been comparatively investigated when assessing the ecosystem stability of eroding landscapes. In this study, soil fungal communities in topsoil (0-5 cm) and subsoil (5-10 cm) on simulated eroding slopes of three slope gradients, i.e., 5°, 10°, and 20°, and in the corresponding depositional zones were examined from 2015 to 2017 in the region of the Chinese Loess Plateau. The results showed that, compared with that in the 5° reference slopes, soil fungal richness in the topsoil and subsoil of the 10° and 20° eroding slopes was 11.8-24.9% lower. However, the richness increased by 2.3-22.7% in the subsoil of the depositional zones, yet not in the topsoil. Soil fungal community compositions in both topsoil and subsoil differed between depositional zones and reference slopes but not between eroding slopes and reference slopes. The differentiation of fungal richness and community compositions between eroding slopes and depositional zones increased with slope gradients, regardless of the topsoil and the subsoil. Saprotrophic fungi levels were 22.5-48.0% lower and pathogenic fungi were 45.2-193.3% higher in the subsoil of the depositional zones with 10° and 20° slopes than in the subsoil of the 5° reference slopes. Soil fungal network on the eroding slope was more complex than that in the depositional zone, suggesting more extensive interactions of fungal taxa and higher community stability potential on eroding slopes. The decreasing soil moisture, organic matter, and other properties on the eroding slopes, in contrast with these properties increasing in the depositional zones, were responsible for the variations in fungal richness and community composition. The divergent responses of soil fungal communities to soil erosion and deposition emphasized the complexity and variability of fungal communities during the soil erosion-deposition processes.


Assuntos
Micobioma , Solo , Ecossistema , Erosão do Solo , Microbiologia do Solo
18.
Sci Total Environ ; 756: 144146, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33298321

RESUMO

Subsoil exposure due to factors including erosion and terracing, evidently decreases soil organic carbon storage and productivity, but the responses of bacterial communities and their carbon dynamics remain unclear. Soils from 0-20 cm, 20-60 cm and 60-100 cm were collected from three 100 cm profiles in bare land on the Loess Plateau, and incubated in buried pots for a year (July 2016 to July 2017) to simulate subsoil exposure, with ongoing monitoring of the microbial mineralization rate of soil organic carbon (Kc), using Li-Cor 8100. At the end of the incubation period, the exposed soil and the in situ control soil were sampled to investigate changes in bacterial community composition, as represented by 16S rRNA, and the activities of enzymes involved in soil carbon cycling. Both copiotrophic (Actinobacteria and Alphaproteobacteria) and oligotrophic (Thermoleophilia) groups were stimulated in the exposed vs. control soil at 20-60 and 60-100 cm. The exposed vs. control soil from 60 to 100 cm produced the greatest bacterial responses, such as greater diversity and altered keystone groups (Thermoleophilia vs. unidentified Acidobacteria). Enzyme activities were greater in the exposed vs. control soil at both 20-60 cm (ß-D-xylosidase and cellobiohydrolase) and 60-100 cm (ß-D-xylosidase and ß-D-glucosidase). The exposed soil from 20-60 cm and 60-100 cm had lower Kc and Q10 values than those at 0-20 cm. Our findings revealed the existence of bacterial depth-specific responses to subsoil exposure, and highlight the effect of anthropogenic soil redistribution on soil carbon flux and its potential responses to future climate change.


Assuntos
Carbono , Solo , Bactérias , RNA Ribossômico 16S , Microbiologia do Solo
19.
J Hazard Mater ; 402: 123776, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33254787

RESUMO

The metal-organic frameworks (MOFs) functionalized palygorskite (Pal) hybrid as a novel multicolor fluorescence probe for the detection of bacterial spore biomarker-dipicolinic acid (DPA), had been prepared via in-situ growth. The MOFs can effectively encapsulate dye molecules on the surface of Pal, and the rich carboxyl groups on its surface can coordinate with europium ions (Eu3+), forming a highly sensitive recognition group. The results indicated that the limit of detection (LOD) of this multicolor fluorescence probe was as low as 9.3 nM and was obviously lower than the amount of anthrax spores infecting the human body (60 µM). Moreover, a wide linear range from 0 to 35 µM was obtained. The high specific surface area of Pal, as well as the permanent porosity and suitable binding sites of Eu3+-doped MOFs may play a major role in the sensitivity and linear detection range. The multicolor fluorescence strategy made full use of the diversity of fluorescence signals collected by dye molecules and lanthanide ions, which can realize the real-time and on-site detection through the smartphone with a color-scanning application (APP). The practicability of this probe was further verified by detecting DPA released by non-infectious Bacillus subtilis.


Assuntos
Estruturas Metalorgânicas , Esporos Bacterianos , Biomarcadores , Argila , Corantes Fluorescentes , Humanos , Smartphone
20.
J Stroke Cerebrovasc Dis ; 29(12): 105400, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33096491

RESUMO

OBJECTIVE: The present study aimed to summarize the clinical characteristics, therapeutic effects, and long-term prognosis of cases confirmed with primary angiitis of the central nervous system (PACNS) by biopsy, analyze the risk factors, and provide clinical guidance for the diagnosis and treatment of the disease. METHODS: Retrospective analysis was performed on 28 cases of PACNS confirmed by biopsy, and the age, gender, pathological results, course of the disease, imaging manifestations, treatment, and prognosis of the patients were analyzed and summarized. RESULTS: The cohort (age 16-60 years) comprised of 16 males. The average time from the visit to diagnosis was 6 months. The first symptom was chronic headache in 18 patients. The pathological results were accompanied by demyelination in 10 cases and glial hyperplasia in 6 cases. A total of 27 patients received treatments including glucocorticoid+cyclophosphamide; of these, 3 cases of craniotomy were improved. Among the 28 patients, 15 patients improved after the treatment, 12 patients had no significant improvement, and 1 patient was deceased. Patients with a long course of the disease before diagnosis, a Karnofsky performance status (KPS) score <60 at the time of diagnosis, a behavioral, cognitive abnormality before treatment, and a short-term relapse (0.3-1 month) have a poor outcome. CONCLUSIONS: PACNS patients are prone to misdiagnosis and mistreatment, with unknown etiology and poor prognosis due to delayed treatment. Therefore, early biopsy, pathological diagnosis, and timely treatment with glucocorticoid shock are recommended, and patients with obvious mass effect should be treated by surgical resection.


Assuntos
Sistema Nervoso Central/patologia , Vasculite do Sistema Nervoso Central/patologia , Adolescente , Adulto , Biópsia , Craniotomia , Diagnóstico Precoce , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tempo para o Tratamento , Vasculite do Sistema Nervoso Central/etiologia , Vasculite do Sistema Nervoso Central/terapia , Adulto Jovem
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