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1.
Appl Opt ; 62(28): 7367-7372, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855504

RESUMO

Non-line-of-sight (NLOS) optical camera communications (OCC) exhibit greater link availability and mobility than line-of-sight links, which are more susceptible to blocking and shadowing. In this work, we propose an NLOS OCC system, where the data signal is mapped into color pulse width modulation (CPWM) symbols prior to transmission using a red-, green-, and blue light-emitting diode. A convolutional-neural-network-based receiver is used to demodulate the CPWM signal. Based on experimental results, the proposed scheme effectively mitigates the effects of diffuse reflection induced intersymbol interference, resulting in an increased data transmission rate to 7.2 kbps over a link span of more than 2 m, which is typical for indoor applications.

2.
Ying Yong Sheng Tai Xue Bao ; 34(12): 3340-3346, 2023 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-38511373

RESUMO

To understand the role of denitrifying microbes during vegetation recovery in karst regions, we determined the basic physicochemical properties and abundance of denitrifying microbial functional genes (nirS, nirK, fungal nirK, p450nor, and nosZ) of 13 collected soil samples under three land use types (cropland, grassland, and plantation) in Northwest Guangxi, and investigated the changes in the abundance of denitrifying microbial functional genes and their driving factors. Results showed that soil pH, soil organic carbon, total nitrogen (TN), and exchangeable calcium (Caexe) in plantation soil were significantly higher than those in cropland and grassland. The abundance of nirS, nirK, p450nor, and nosZ in plantation soil were significantly higher than those in cropland and grassland. Soil pH, TN, and Caexe were positively correlated with the abundance of denitrifying functional genes nirS, nirK, and p450nor. Results of redundancy analysis showed that soil Caexe, pH and TN were the primary factors influencing the abundance of denitrifying functional genes, which accounted for 34.1%, 20.1%, and 16.1% of the total variation, respectively. Such a result suggested that Caexe was the main driver of changes in denitrifying functional genes under different land use types. Overall, vegetation restoration (plantation) could effectively increase soil denitrifying microbe genes abundance in the karst region of Northwest Guangxi, and consequently influence soil nitrogen cycling.


Assuntos
Carbono , Solo , Solo/química , Carbono/análise , China , Genes Bacterianos , Nitrogênio/análise , Microbiologia do Solo , Desnitrificação
3.
Sci Total Environ ; 825: 154007, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35192825

RESUMO

Soil moisture (SM) and groundwater (GW) depletion triggered by anthropogenic and natural climate change are influencing food security via crop production per capita decrease in the Nile River Basin (NRB). However, to the best of our understanding, the causes and impact of SM and GW depletion have not been studied yet comprehensively in the NRB. In this study, GW is derived from the Gravity Recovery and Climate Experiment (GRACE) mission, and SM was estimated using the Triple Collocation Analysis (TCA). SM/GW depletion causes were evaluated via the Land Use Land Cover (LULC) and rainfall/temperature change analysis, whereas impact analysis focused on crop production per capita reduction (food insecurity) during SM depletion. The major findings of this study are 1) TCA analyzed SM show a decreasing trend (-0.06 mm/yr) in agricultural land while increasing (+0.21 mm/yr) in forest land, 2) LULC analysis indicated a vast increment of agricultural land (+9%) and bareland (+9%) although the decreasing pattern of forest (-1.5%) and shrubland (-6.9%) during 1990-2019; 3) the impact of SM depletion on crop production per capita caused food insecurity during a drought year, 4) agriculture drought indices and crop production per capita show high correlations (R2 = 0.86 to 0.60) demonstrated that Vegetation Supply Water Index (VSWI) could provide strategic warning of drought impacts on rainfed agricultural regions. In conclusion, SM and GW depletions are mainly caused by human-induced and climate change factors imposing food insecurity challenges in the NRB coupled with increasing temperature and excessive water extraction for irrigation. Therefore, it is highly recommended to rethink and reverse SM/GW depletion causing factors to sustain food security in NRB and similar basins.


Assuntos
Água Subterrânea , Solo , Agricultura , Produção Agrícola , Humanos , Água
4.
Chin Med J (Engl) ; 134(14): 1695-1700, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34397596

RESUMO

BACKGROUND: Glucose control is an important aspect in managing critically ill patients. The goal of this study was to compare the effects of sequential feeding (SF) and continuous feeding (CF) on the blood glucose of critically ill patients. METHODS: A non-inferiority randomized controlled trial was adopted in this study. A total of 62 patients who were fed enteral nutritional suspension through gastric tubes were enrolled. After achieving 80% of the nutrition target calories (25 kcal·kg-1·day-1) through CF, the patients were then randomly assigned into SF and CF groups. In the SF group, the feeding/fasting time was reasonably determined according to the circadian rhythm of the human body as laid out in traditional Chinese medicine theory. The total daily dosage of the enteral nutritional suspension was equally distributed among three time periods of 7 to 9 o'clock, 11 to 13 o'clock, and 17 to 19 o'clock. The enteral nutritional suspension in each time period was pumped at a uniform rate within 2 h by an enteral feeding pump. In the CF group, patients received CF at a constant velocity by an enteral feeding pump throughout the study. Blood glucose values at five points (6:00/11:00/15:00/21:00/1:00) were monitored and recorded for seven consecutive days after randomization. Enteral feeding intolerance was also recorded. Non-inferiority testing was adopted in this study, the chi-square test or Fisher test was used for qualitative data, and the Mann-Whitney U test was used for quantitative data to determine differences between groups. In particular, a repeated measure one-way analysis of variance was used to identify whether changes in glucose value variables across the time points were different between the two groups. RESULTS: There were no significant demographic or physiological differences between the SF and CF groups (P > 0.050). The average glucose level in SF was not higher than that in CF (8.8 [7.3-10.3] vs. 10.7 [9.1-12.1] mmol/L, Z = -2.079, P for non-inferiority = 0.019). Hyperglycemia incidence of each patient was more common in the CF group than that in the SF group (38.4 [19.1-63.7]% vs. 11.8 [3.0-36.7]%, Z = -2.213, P = 0.027). Hypoglycemia was not found in either group. Moreover, there was no significant difference during the 7 days in the incidence of feeding intolerance (P > 0.050). CONCLUSIONS: In this non-inferiority study, the average blood glucose in SF was not inferior to that in CF. The feeding intolerance in SF was similar to that in CF. SF may be as safe as CF for critically ill patients. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03439618; https://clinicaltrials.gov/ct2/show/record/NCT03439618.


Assuntos
Glicemia , Hiperglicemia , Estado Terminal , Ingestão de Energia , Nutrição Enteral , Humanos , Recém-Nascido
5.
Front Psychol ; 11: 1749, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849037

RESUMO

Under the analysis of the psychological level of entrepreneurs, the study focuses on discussing the relationship between the salary gap and enterprise innovation efficiency. It provides a reference basis for promoting employee innovation activities and improving the market competitiveness of enterprises. First, the role of entrepreneur psychology in decision-making was explained theoretically. Based on this, the relationship between the salary gap of employees and enterprise innovation was analyzed from a theoretical perspective. In the empirical analysis, this paper selected the data of China's A-share manufacturing listed enterprises from 2012 to 2016 as the research sample. The explanatory variables include the salary of senior management, the salary of the ordinary employee and salary gap. The explained variable is enterprise innovation efficiency. By constructing an econometric model, this study used a multiple regression model to empirically analyze the correlation between the salary gap and innovation efficiency. The regression coefficients between monetary salary and equity salary of senior managers and enterprise innovation performance are 5.545 and 1.003, respectively. The regression coefficient between the salary of the ordinary employee and enterprise innovation efficiency is 8.357. The regression coefficient between the internal salary gap of the senior management team and the enterprise innovation efficiency is 3.552, both of which show a significant positive correlation at the 1% level. The regression coefficient between the salary gap between senior managers and ordinary employees and the enterprise innovation performance is -3.032, which is significantly negatively correlated at the 5% level. The internal salary gap of the senior management team has a significant positive effect on enterprise innovation efficiency. The salary gap between senior managers and ordinary employees has a negative effect on enterprise innovation efficiency. Enterprises should optimize the salary structure from two levels of senior managers and ordinary employees, to stimulate the work enthusiasm of employees at all levels, and promote enterprise innovation.

6.
BMC Anesthesiol ; 18(1): 187, 2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30537939

RESUMO

BACKGROUND: Central venous oxygen saturation (ScvO2), venous-arterial blood carbon dioxide partial pressures difference (Pv-aCO2), venous-arterial blood carbon dioxide partial pressures difference/arterial-venous oxygen difference ratio (Pv-aCO2/Ca-vO2) and lactate are important parameters employed during shock resuscitation. We designed this study to confirm the effects of time delay and body temperature on measurements of these four parameters. METHODS: Arterial and central venous blood samples were simultaneously drawn by plastic syringes via indwelling intra-arterial and central venous catheters from critically ill patients. Blood gas analyses were performed on both samples and repeated after 10, 20, 30, 40, 50 and 60 min. Patients were divided into a control group and a high temperature group according to whether the body temperature was greater than 38 °C. RESULTS: A total of 30 critically ill patients were enrolled. There was a trend of increasing values for ScvO2, Pv-aCO2, Pv-aCO2/Ca-vO2 and lactate over time (P < 0.001). The ScvO2 differences were all lower in high temperature group after 10, 20, 30, 40, 50 and 60 min when compared to the corresponding differences in the control group (P < 0.05). The differences in lactate values were slightly higher in the high temperature group, relative to the control group after 20, 30, 40, 50 and 60 min (P < 0.05). CONCLUSIONS: Measurements of ScvO2, Pv-aCO2, lactate and Pv-aCO2/Ca-vO2 were affected by time delay or body temperature. We recommend that arterial and central venous blood gas samples be analyzed quickly within 10 min, especially for patients with body temperature <38 °C. TRIAL REGISTRATION: ChiCTR, ChiCTR1800014484 . Registered 16 January 2018.


Assuntos
Temperatura Corporal/fisiologia , Dióxido de Carbono/sangue , Ácido Láctico/sangue , Oxigênio/sangue , Idoso , Gasometria , Estado Terminal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão Parcial , Fatores de Tempo
7.
Analyst ; 140(8): 2656-63, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25697303

RESUMO

A metal (Co)-Organic Framework (Co-MOF) was first found to catalyze the chemiluminescence (CL) of luminol. On the basis of X-ray photoelectron spectroscopy, powder X-ray diffraction, CL spectral, UV-visible absorption spectral, and electron spin resonance (ESR) spectral studies, as well as the research of the influence of various free radical scavengers, a possible CL mechanism was proposed. The enhanced CL might be attributed to the formation of a peroxide analogous complex between the oxygen-related radicals and the active metal site of the Co-MOF material. The established Co-MOF-luminol CL system was successfully applied to determine L-cysteine (CySH), based on the selective and sensitive enhancing effect of CySH on this CL system. Under the optimized conditions, CySH was selectively detected in the range 0.1-10 µM with a detection limit of 18 nM. This novel CL system obviously gives impetus to the new research field of metal-organic frameworks (MOFs) in chemiluminescence.


Assuntos
Cobalto/química , Cisteína/análise , Medições Luminescentes/métodos , Compostos Organometálicos/química , Cisteína/química , Luminol/química
8.
J Colloid Interface Sci ; 369(1): 381-7, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22218342

RESUMO

SiO(2)/graphene composite was prepared through a simple two-step reaction, including the preparation of SiO(2)/graphene oxide and the reduction of graphene oxide (GO). The composite was characterized by UV-Vis spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscope, and X-ray photoelectron spectroscopy, and what is more, the adsorption behavior of as-synthesized SiO(2)/graphene composite was investigated. It was interestingly found that the composite shows high efficiency and high selectivity toward Pb(II) ion. The maximum adsorption capacity of SiO(2)/graphene composite for Pb(II) ion was found to be 113.6 mg g(-1), which was much higher than that of bare SiO(2) nanoparticles. The results indicated that SiO(2)/graphene composite with high adsorption efficiency and fast adsorption equilibrium can be used as a practical adsorbent for Pb(II) ion.

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