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1.
Heliyon ; 10(3): e25304, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38327409

RESUMEN

The urgency to mitigate greenhouse gas emissions from maritime vessels has intensified due to the increasingly stringent directives set forth by the International Maritime Organization (IMO). These directives specifically address energy efficiency enhancements and emissions reduction within the shipping industry. In this context, hydrogen is the much sought after fuel for all the global economies and its applications, for transportation and propulsion in particular, is crucial for cutting down carbon emissions. Nevertheless, the realization of hydrogen-powered vessels is confronted by substantial technical hurdles that necessitate thorough examination. This study undertakes a comprehensive analysis encompassing diverse facets, including distinct variations of hydrogen fuel cells, hydrogen internal combustion engines, safety protocols associated with energy storage, as well as the array of policies and commercialization endeavors undertaken globally for the advancement of hydrogen-propelled ships. By amalgamating insights from these multifaceted dimensions, this paper adeptly encapsulates the myriad challenges intrinsic to the evolution of hydrogen-fueled maritime vessels, while concurrently casting a forward-looking gaze on their prospective trajectory.

2.
Innovation (Camb) ; 2(4): 100168, 2021 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-34746905

RESUMEN

Electro-responsive actuators (ERAs) hold great promise for cutting-edge applications in e-skins, soft robots, unmanned flight, and in vivo surgery devices due to the advantages of fast response, precise control, programmable deformation, and the ease of integration with control circuits. Recently, considering the excellent physical/chemical/mechanical properties (e.g., high carrier mobility, strong mechanical strength, outstanding thermal conductivity, high specific surface area, flexibility, and transparency), graphene and its derivatives have emerged as an appealing material in developing ERAs. In this review, we have summarized the recent advances in graphene-based ERAs. Typical the working mechanisms of graphene ERAs have been introduced. Design principles and working performance of three typical types of graphene ERAs (e.g., electrostatic actuators, electrothermal actuators, and ionic actuators) have been comprehensively summarized. Besides, emerging applications of graphene ERAs, including artificial muscles, bionic robots, human-soft actuators interaction, and other smart devices, have been reviewed. At last, the current challenges and future perspectives of graphene ERAs are discussed.

3.
Front Cell Dev Biol ; 9: 791221, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35004687

RESUMEN

Testis is the primary organ of the male reproductive tract in mammals that plays a substantial role in spermatogenesis. Improvement of our knowledge regarding the molecular mechanisms in testicular development and spermatogenesis will be reflected in producing spermatozoa of superior fertility. Evidence showed that N6-Methyladenosine (m6A) plays a dynamic role in post-transcription gene expression regulation and is strongly associated with production traits. However, the role of m6A in bovine testis has not been investigated yet. In this study, we conducted MeRIP-Seq analysis to explore the expression profiles of the m6A and its potential mechanism underlying spermatogenesis in nine bovine testes at three developmental stages (prepuberty, puberty and postpuberty). The experimental animals with triplicate in each stage were chosen based on their semen volume and sperm motility except for the prepuberty bulls and used for testes collection. By applying MeRIP-Seq analysis, a total of 8,774 m6A peaks and 6,206 m6A genes among the studied groups were identified. All the detected peaks were found to be mainly enriched in the coding region and 3'- untranslated regions. The cross-analysis of m6A and mRNA expression exhibited 502 genes with concomitant changes in the mRNA expression and m6A modification. Notably, 30 candidate genes were located in the largest network of protein-protein interactions. Interestingly, four key node genes (PLK4, PTEN, EGR1, and PSME4) were associated with the regulation of mammal testis development and spermatogenesis. This study is the first to present a map of RNA m6A modification in bovine testes at distinct ages, and provides new insights into m6A topology and related molecular mechanisms underlying bovine spermatogenesis, and establishes a basis for further studies on spermatogenesis in mammals.

4.
Front Chem ; 8: 692, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32903458

RESUMEN

The surface wettability of plants exhibits many unique advantages, which enhances the environmental adaptability of plants. In view of the rapid development of responsive materials, smart surfaces have been explored extensively to regulate surface wettability through external stimuli. Herein, we summarized recent advancements in bioinspired surfaces with switchable wettability. Typical bioinspired surfaces with switchable wettability and their emerging applications have been reviewed. In the end, we have discussed the remaining challenges and provided perspective on future development.

5.
ACS Appl Mater Interfaces ; 12(22): 25435-25443, 2020 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-32401489

RESUMEN

Solar interfacial evaporation has been recognized as a versatile energy conversion protocol for cutting-edge applications such as water treatment and power generation (e.g., hydro voltaic effect). Recently, to enhance water evaporation rates, water temperature and evaporation area have been considered as essential ingredients, and thus photothermal materials and three-dimensional hierarchical structures have been developed to promote light-to-heat conversion efficiency and enhance interfacial evaporation. However, less attention has been paid to the airflow effect, because the interfacial floatability of photothermal membranes should be considered under air blast. Here, inspired from the stable interfacial floatability of lotus leaves, we report the airflow enhanced solar interfacial evaporation approach using a graphene-based Janus membrane. Laser-induced graphene (LIG) film was treated unilaterally by O2 plasma, forming a LIG/oxidized LIG (LIG-O) Janus membrane with distinct wettability on two sides. Higher water evaporation rate of 1.512 kg m-2 h-1 is achieved. The high solar interfacial evaporation performance can be attributed to the two advantages: (i) the combination of microscale capillary water transporting and nanoscale light trapping; (ii) hydrophobic/hydrophilic Janus membrane for stable interfacial floatability under airflow. Our approach is feasible for developing high-performance solar interfacial evaporation devices for practical clean energy utilization.

6.
Gene ; 689: 90-96, 2019 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-30572095

RESUMEN

Copy number variation is a large genome variation which usually happens in the noncoding-region, and it may occur at the locus associated with the functional gene to further influence the phenotype. Potassium inwardly-rectifying channel, subfamily J 12 (KCNJ12) gene expressed widely in cardiomyocytes and neurons, plays an important role in tumor therapy and muscle movement regulation. In this study, we detected the distribution of CNVs for KCNJ12 gene in 404 individuals belonging to four Chinese cattle breeds (NY, JX, JA and GF). We also investigated the KCNJ12 gene expression in different tissues of JX cattle. Additionally, we examined the association of two CNV regions (CNV1: 1,600 bp, intron 1; CNV2: 4,800 bp, intergenic) with growth traits. The statistical analyses indicated that the CNV1 is associated with the body length, rump length and weight in JX cattle population (P < 0.05); and there has a significant association with the body length, chest circumference, and body weight in GF cattle (P < 0.05).The CNV2 had a significant effect on the body length and body weight in JX cattle (P < 0.05); the body length, chest circumference, rump length and body weight in GF cattle (P < 0.01 or P < 0.05). The copy numbers of KCNJ12 gene presented the negative correlations with the transcript level of gene in skeletal muscles (P < 0.05). Our results provide evidence that CNV1 and CNV 2 in KCNJ12 are associated with growth traits in two cattle populations and may be used as candidates for marker-assisted selection and breeding management in cattle.


Asunto(s)
Tamaño Corporal/genética , Peso Corporal/genética , Bovinos/crecimiento & desarrollo , Bovinos/genética , Canales de Potasio de Rectificación Interna/genética , Animales , Cruzamiento , China/epidemiología , Variaciones en el Número de Copia de ADN , Femenino , Estudios de Asociación Genética/veterinaria , Desequilibrio de Ligamiento , Fenotipo , Carácter Cuantitativo Heredable
7.
Phys Chem Chem Phys ; 20(31): 20571-20574, 2018 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-30058658

RESUMEN

The electron localization in Nb-doped CaMnO3 is analyzed in terms of the space and energy distribution of electronic states employing first-principles calculations. The energy difference of Mn 3d states and Nb 4d states makes NbO6 octahedra impede electrical conduction, so the random distribution of Nb in lattices leads to the localization of electrons near the bottom of the conduction bands. Therefore, although more carriers are introduced when Nb-doping content increases, both the electrical conductivity and absolute thermopower decrease in Nb heavy doped CaMnO3. The calculated transport properties agree well with the experimental data, supporting the analysis of localization.

8.
Ying Yong Sheng Tai Xue Bao ; 27(4): 1039-1045, 2016 Apr 22.
Artículo en Chino | MEDLINE | ID: mdl-29732757

RESUMEN

By performing a pot experiment, the study compared leaf and litter element concentration between the dry-red soil and vertisols, and analyzed the interactive effects of soil types and species on leaf nutrient concentration and nutrient resorption efficiency. The results showed that the soil type significantly affected the concentrations of N, P, Ca, Mg, Cu, Zn, Fe and N:P in leaves as well as the concentrations of N, P, Mn and N:P in leaf litters. Concentrations of N, Mn and N:P in leaves and litters derived from the dry-red soil were significantly higher than those from the vertisols. In contrast, concentrations of P, Ca, Mg, Fe, Cu and Zn in leaves and concentration of P in litters derived from the dry-red soil were significantly lower than those from the vertisols. Leaf N concentration was 34.8% higher, and leaf P concentration was 40.0% lower from the dry-red soil compared with those from the vertisols. N, P and K showed net resorption while the other elements showed accumulating patterns when leaf was senesced. Accumulation of Ca, Mg and Mn of senesced leaves was significantly higher on the dry-red soil than on the vertisols. Species identities only significantly affected leaf N concentration. Interactions of species and soil taxonomy significantly affected nutrient concentration neither in leaves nor in leaf litters, indicating that soil taxonomy influenced plant nutrient concentration in a similar way across multiple species. The influences of soil types on plant element concentration could have further effects on litter decomposition, plant-soil nutrient feedback and biogeochemical cycle in this dry and hot valley.


Asunto(s)
Hojas de la Planta/química , Plantas/química , Suelo/química , China , Ambiente , Nitrógeno , Fósforo , Potasio
9.
Ying Yong Sheng Tai Xue Bao ; 24(4): 956-60, 2013 Apr.
Artículo en Chino | MEDLINE | ID: mdl-23898651

RESUMEN

Taking the arid-hot valley of Jinsha River, Southwest China as the object, a comparative study was made on the plant leaf N, P, and K concentrations and ratios as well as their relationships with species dominance in the restoration area and disturbed area, aimed to understand the effects of ecosystem restoration on the plant leaf stoichoimetric characteristics. Ecosystem restoration decreased the plant leaf N and P concentrations and P/K ratio significantly, but had lesser effects on the plant leaf K concentration. In restoration area, the plant leaf N, P, and K concentrations were averagely 10. 405, 0. 604, and 9. 619 g kg-1, being 16. 9% , 34. 9% , and 4. 7% lower than those in disturbed area, respectively. In restoration area, species dominance was significantly negatively correlated with plant leaf P concentration; while the species dominance in disturbed area had a significant negative correlation with plant leaf K concentration. Ecosystem restoration altered the slope and intercept of the scaling relationships among the plant leaf N, P, and K. No significant differences were observed in the leaf N, P, and K concentrations of the same plant species between restoration area and disturbed area, suggesting that the changes of plant leaf stoichiometric characteristics were mainly driven by the shift of species composition in the plant community.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Nitrógeno/análisis , Fósforo/análisis , Hojas de la Planta/química , Potasio/análisis , China , Restauración y Remediación Ambiental , Calor , Desarrollo de la Planta , Especificidad de la Especie
10.
Zhonghua Yu Fang Yi Xue Za Zhi ; 47(3): 249-54, 2013 Mar.
Artículo en Chino | MEDLINE | ID: mdl-23866752

RESUMEN

OBJECTIVE: To study the prevalence of occupational musculoskeletal disorders (OMSD) of male steelworkers and explore its occupational and individual risk factors. METHODS: 1620 male workers from a steel mill were selected as subjects through random cluster sampling in 2010. A revised Nordic Musculoskeletal disorder standard questionnaire and a questionnaire from National Institute for Occupational and Health of the Netherlands were used to ask and record the OMSD and its risk factors. The questionnaires were filled in by the workers. Annual prevalence of OMSD in different parts of the body were counted according to different age, working years and educational level, logistic regression was used to analyze its influence factors. RESULTS: OMSD in these workers primarily located in waist, neck and shoulders, annual prevalence were 51.0% (825), 48.5% (785) and 37.7% (610) respectively. Annual prevalence of other body parts were 28.0% (454) for back, 23.6% (383) for knee, 21.0% (341) for wrist, 17.9% (290) for ankle/foot, 14.1% (229) for elbow and 12.7% (205) for coxa. The annual prevalence of OMSD for each part tended to increase with age, mainly in waist and neck. Of the different age groups ≤ 24, 25 - 29, 30 - 34, 35 - 39, 40 - 44, 45 - 49, ≥ 50, the annual prevalence in waist was 26.4% (43/163), 37.8% (71/188), 52.8% (162/307), 55.6% (160/288), 53.8% (99/184), 55.9% (80/143), 61.6% (204/331) respectively (χ(2) = 72.5, P < 0.05); correspondingly, the annual prevalence in neck was 22.7% (37/163), 40.4% (76/188), 50.2% (154/307), 48.6% (140/288), 56.0% (103/184), 53.1% (76/143), 57.7% (191/331) respectively (χ(2) = 65.3, P < 0.05). The annual prevalence of OMSD increased with the working years. Of the different working years groups ≤ 4, 5 - 9, 10 - 14, 15 - 19, 20 - 24, 25 - 29, ≥ 30, the annual prevalence in waist was 30.2% (85/281), 46.2% (66/143), 56.4% (162/287), 56.8% (137/241), 50.6% (78/154), 59.2% (90/152), 60.7% (173/285) respectively (χ(2) = 71.3, P < 0.05);correspondingly, the annual prevalence in neck was 28.8% (81/281), 49.0% (70/143), 52.6% (151/287), 50.2% (121/241), 51.9% (80/154), 53.9% (82/152), 59.3% (169/285) respectively (χ(2) = 61.5, P < 0.05). The annual prevalence of OMSD decreased with education level. Of the different groups of education level (junior high school level and below, senior high school level, university level or above), the OMSD prevalence in waist was 61.5% (176/286), 61.9% (359/692), 44.2% (272/615) respectively (χ(2) = 26.0, P < 0.05);correspondingly, the annual prevalence in neck was 56.3% (161/286), 50.0% (346/692), 42.3% (260/615)respectively (χ(2) = 21.2, P < 0.05). Univariate logistic regression showed that the work load factors such as the working years ≥ 30 (OR = 3.562, 95%CI: 2.514 - 5.046), maintain substantial stoop for a long time (OR = 2.003, 95%CI: 1.612 - 2.488), often stooping with vast scale (OR = 1.897, 95%CI: 1.557 - 2.312), and torso repeating same action many times per minute (OR = 1.870, 95%CI: 1.529 - 2.288) could increase the annual prevalence of OMSD in waist most likely (P < 0.05). The working years ≥ 30 (OR = 3.597, 95%CI: 2.535 - 5.105), neck leaning forward (OR = 2.455, 95%CI: 2.010-2.99), neck leaning back (OR = 1.999, 95%CI: 1.569 - 2.546), and neck rotation (OR = 2.381, 95%CI: 1.907 - 2.972) were main risk factors causing OMSD in neck (P < 0.05). CONCLUSION: The most serious musculoskeletal disorders of male steelworkers were waist and neck pain. Personal factors such as age, working years, work load factors such as harmful working postures, manual heavy lifting, and labour organizational factors such as work overtime were the main risk factors of musculoskeletal disorders to the male steelworkers.


Asunto(s)
Enfermedades Musculoesqueléticas/epidemiología , Enfermedades Profesionales/epidemiología , Carga de Trabajo , Adulto , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Encuestas y Cuestionarios
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(11): 3136-9, 2010 Nov.
Artículo en Chino | MEDLINE | ID: mdl-21284200

RESUMEN

In the present study, a method for determination of BrO3- and Br- using ion chromatograghy coupling with inductively coupled plasma mass spectrometry (IC-ICP-MS) was developed. BrO3- and Br- were separated on a Hamilton PRP X-100 (150 x 4.1 mm, 10 microm) column guarding with a On-guard II RP (4 x 50 mm) column with 10 mmol x L(-1) NH4NO3 eluent solution at 2 mL x min(-1). By using 200 microL sample loop, the detection limits for BrO3- and Br were 0.35 and 0.36 microg x L(-1), respectively. BrO3- had good linearity in the range 4.8-160.0 ng x L(-1). The standard solution linear equation was y = 250.31x-45.43, and R2 = 0.9999. Br had good linearity in the range 4.2-140.0 ng x L(-1). The standard solution linear equation was y = 186.84x-127.10, and R2 = 0.9994. Recoveries of spiked samples were 98.9%-109.5% and 97.4%-106.1%, respectively. The samples included various kinds of Chinese patent drugs, waters, and beverages. Among them, 14 bottled drinking waters and 2 kinds of tap waters were found containing BrO-, while other samples were under BrO3- detection limit. Br- was detected in all samples.


Asunto(s)
Bebidas/análisis , Compuestos de Bromina/análisis , Cromatografía , Agua Potable/análisis , Medicamentos Herbarios Chinos/análisis , Límite de Detección , Espectrometría de Masas
13.
Artículo en Chino | MEDLINE | ID: mdl-14761400

RESUMEN

OBJECTIVE: To explore the biomarkers of early diagnosis in patients with polycyclic aromatic hydrocarbons (PAHs)-related lung cancer for the application to detection of occupational lung cancer or related lung cancer. METHODS: Western dot blotting was used to explore the expression of ras, p53 and heat stress protein 70 (HSP70) in 29 patients with PAHs-related lung cancer (LC), and 28 patients with non-cancerous pulmonary disease, and 30 healthy controls. RESULTS: The positive detection rates of P21, P53, and HSP70 in LC group (58.62%, 34.48%, 41.38% respectively) were higher than those in non-cancerous pulmonary disease group (14.29%, 7.14%, 10.71% respectively, P < 0.01). The sensitivity of P21, P53 and HSP70 were 58.62%, 34.48% and 41.38% respectively, negative predictive value (NPV) were 68.42%, 78.05% and 63.04% respectively. The co-detection of the three proteins mentioned above produced a sensitivity of 82.76% with a NPV of 78.26% (P < 0.05). Of 18 cases of LC with negative cytology, 13 (72.22%) were found HSP21, P53 or HSP70 positive. CONCLUSIONS: Co-detection of the P21, P53, and HSP70 may be used as the screening marker for diagnosis of PAHs-related lung cancer, and may supplement the diagnostic value of conventional cytology.


Asunto(s)
Biomarcadores/análisis , Neoplasias Pulmonares/patología , Hidrocarburos Policíclicos Aromáticos/envenenamiento , Anciano , Western Blotting , Estudios de Casos y Controles , Proteínas HSP70 de Choque Térmico/análisis , Humanos , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/metabolismo , Persona de Mediana Edad , Exposición Profesional , Proteínas Proto-Oncogénicas p21(ras)/análisis , Proteína p53 Supresora de Tumor/análisis
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