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1.
Adv Mater ; 36(25): e2400810, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38569213

RESUMEN

The catalytic activation of the Li-S reaction is fundamental to maximize the capacity and stability of Li-S batteries (LSBs). Current research on Li-S catalysts mainly focuses on optimizing the energy levels to promote adsorption and catalytic conversion, while frequently overlooking the electronic spin state influence on charge transfer and orbital interactions. Here, hollow NiS2/NiSe2 heterostructures encapsulated in a nitrogen-doped carbon matrix (NiS2/NiSe2@NC) are synthesized and used as a catalytic additive in sulfur cathodes. The NiS2/NiSe2 heterostructure promotes the spin splitting of the 3d orbital, driving the Ni3+ transformation from low to high spin. This high spin configuration raises the electronic energy level and activates the electronic state. This accelerates the charge transfer and optimizes the adsorption energy, lowering the reaction energy barrier of the polysulfides conversion. Benefiting from these characteristics, LSBs based on NiS2/NiSe2@NC/S cathodes exhibit high initial capacity (1458 mAh·g⁻1 at 0.1C), excellent rate capability (572 mAh·g⁻1 at 5C), and stable cycling with an average capacity decay rate of only 0.025% per cycle at 1C during 500 cycles. Even at high sulfur loadings (6.2 mg·cm⁻2), high initial capacities of 1173 mAh·g⁻1 (7.27 mAh·cm⁻2) are measured at 0.1C, and 1058 mAh·g⁻1 is retained after 300 cycles.

2.
Neuron ; 112(1): 93-112.e10, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38096817

RESUMEN

Astrocytes play crucial roles in regulating neural circuit function by forming a dense network of synapse-associated membrane specializations, but signaling pathways regulating astrocyte morphogenesis remain poorly defined. Here, we show the Drosophila lipid-binding G protein-coupled receptor (GPCR) Tre1 is required for astrocytes to establish their intricate morphology in vivo. The lipid phosphate phosphatases Wunen/Wunen2 also regulate astrocyte morphology and, via Tre1, mediate astrocyte-astrocyte competition for growth-promoting lipids. Loss of s1pr1, the functional analog of Tre1 in zebrafish, disrupts astrocyte process elaboration, and live imaging and pharmacology demonstrate that S1pr1 balances proper astrocyte process extension/retraction dynamics during growth. Loss of Tre1 in flies or S1pr1 in zebrafish results in defects in simple assays of motor behavior. Tre1 and S1pr1 are thus potent evolutionarily conserved regulators of the elaboration of astrocyte morphological complexity and, ultimately, astrocyte control of behavior.


Asunto(s)
Proteínas de Drosophila , Pez Cebra , Animales , Astrocitos/metabolismo , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Fosfolípidos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Esfingosina-1-Fosfato/metabolismo
3.
Epidemiol Infect ; 151: e99, 2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37226697

RESUMEN

Large gatherings of people on cruise ships and warships are often at high risk of COVID-19 infections. To assess the transmissibility of SARS-CoV-2 on warships and cruise ships and to quantify the effectiveness of the containment measures, the transmission coefficient (ß), basic reproductive number (R0), and time to deploy containment measures were estimated by the Bayesian Susceptible-Exposed-Infected-Recovered model. A meta-analysis was conducted to predict vaccine protection with or without non-pharmaceutical interventions (NPIs). The analysis showed that implementing NPIs during voyages could reduce the transmission coefficients of SARS-CoV-2 by 50%. Two weeks into the voyage of a cruise that begins with 1 infected passenger out of a total of 3,711 passengers, we estimate there would be 45 (95% CI:25-71), 33 (95% CI:20-52), 18 (95% CI:11-26), 9 (95% CI:6-12), 4 (95% CI:3-5), and 2 (95% CI:2-2) final cases under 0%, 10%, 30%, 50%, 70%, and 90% vaccine protection, respectively, without NPIs. The timeliness of strict NPIs along with implementing strict quarantine and isolation measures is imperative to contain COVID-19 cases in cruise ships. The spread of COVID-19 on ships was predicted to be limited in scenarios corresponding to at least 70% protection from prior vaccination, across all passengers and crew.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Navíos , SARS-CoV-2 , Teorema de Bayes , Viaje , Brotes de Enfermedades/prevención & control , Cuarentena
4.
Bioengineering (Basel) ; 10(4)2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37106638

RESUMEN

Heat stress poses a significant challenge to egg production in layer hens. High temperatures can disrupt the physiological functions of these birds, leading to reduced egg production and lower egg quality. This study evaluated the microclimate of laying hen houses using different management systems to determine the impact of heat stress on productivity and hen health. The results showed that the ALPS system, which manages the hen feeding environment, effectively improved productivity and decreased the daily death rate. In the traditional layer house, the daily death rate decreased by 0.045%, ranging from 0.086% to 0.041%, while the daily production rate increased by 3.51%, ranging from 69.73% to 73.24%. On the other hand, in a water-pad layer house, the daily death rate decreased by 0.033%, ranging from 0.082% to 0.049%, while the daily production rate increased by 21.3%, ranging from 70.8% to 92.1%. The simplified hen model helped design the indoor microclimate of commercial layer houses. The average difference in the model was about 4.4%. The study also demonstrated that fan models lowered the house's average temperature and reduced the impact of heat stress on hen health and egg production. Findings indicate the need to control the humidity of inlet air to regulate temperature and humidity, and suggest that Model 3 is an energy-saving and intelligent solution for small-scale agriculture. The humidity of the inlet air affects the temperature experienced by the hens. The THI drops to the alert zone (70-75) when humidity is below 70%. In subtropical regions, we consider it necessary to control the humidity of the inlet air.

5.
Environ Res ; 233: 115483, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-36791838

RESUMEN

BACKGROUND: How indoor air quality affects the temporal associations of long-term exposure to low-level air pollutants with cognition remains unclear. METHODS: This cohort study (2011-2019) included 517 non-demented older adults at baseline with four repeated cognitive assessments. The time-varying exposure to PM2.5, PM10, NO2, SO2, CO, and O3 was estimated for each participant from 1994 to 2019. Indoor air quality was determined by ventilation status and daily indoor time. Generalized linear mixed models were used to analyze the association of air pollutants, indoor air quality, and cognition adjusting for important covariates. RESULTS: Over time, per 2.97 µg/m3 (i.e., an interquartile range) increment of PM2.5 was associated with the poor performance of memory (Z score of a cognitive test, ߈:-0.14), attention (߈:-0.13), and executive function (߈:-0.20). Similarly, per 2.05 µg/m3 increase in PM2.5-10 was associated with poor global cognition [adjusted odds ratio (aOR): 1.48, ߈:-0.28], attention (߈:-0.07), and verbal fluency (߈:-0.09); per 4.94 µg/m3 increase in PM10 was associated with poor global cognition (aOR: 1.78; ߈:-0.37). In contrast, per 2.74 ppb increase in O3 was associated with better global cognition (߈:0.36 to 0.47). These associations became more evident in participants with poor ventilation or short daily indoor time (<12.5 h/day). For global cognition, the exposure to a 10-µg/m3 increment in PM2.5, PM2.5-10, and PM10 corresponded to 1.4, 5.8, and 2.8 years of aging, respectively. CONCLUSION: This study demonstrated how indoor air quality in areas using clean fuels differentially affected the associations of long-term exposure to low-level air pollutants with cognition. Tightening air quality standards may help prevent dementia.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminación del Aire , Humanos , Anciano , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/efectos adversos , Estudios de Cohortes , Contaminación del Aire/análisis , Cognición , Material Particulado/análisis , Exposición a Riesgos Ambientales/análisis , Dióxido de Nitrógeno/análisis
6.
J Formos Med Assoc ; 122(2): 91-97, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36476674

RESUMEN

This mini-review provides the practice guideline recommendations for ventilation of remodeled negative-pressure isolation wards for COVID-19 Patients. Remodeled "quasi-negative-pressure" isolation wards had been proved a feasible, inexpensive, safe, and effective measure to contain nosocomial outbreaks. We should first determine the minimum required ventilation volume of an isolation ward based on the severity of COVID-19 patients. Mechanical ventilation remains the mainstay for achieving the requirement, while the assistance of recirculation is also helpful. Beyond adequate ventilation volume, the "clean to less-clean" directional airflow remains the golden rule for the solution of indoor ventilation. The virus-laden exhaust should be treated with HEPA/UV device or be kept away from living organisms, buildings, and air inlets.


Asunto(s)
COVID-19 , Humanos , Aislamiento de Pacientes , Ventilación , Hospitales , Brotes de Enfermedades
7.
J Phys Chem Lett ; : 5151-5159, 2022 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-35658442

RESUMEN

The rate capability of lithium-ion batteries is highly dependent on the interphase chemistry of graphite anodes. Herein, we demonstrate an anode interphase tailoring based on a novel electrolyte additive, lithium dodecyl sulfate (LiDS), which greatly improves the rate capability and cyclic stability of graphite anodes. Upon application of 1% LiDS in a base electrolyte, the discharge capacity at 2 C is improved from 102 to 240 mAh g-1 and its capacity retention is enhanced from 51% to 94% after 200 cycles at 0.5 C. These excellent performances are attributed to the preferential absorption of LiDS and the as-constructed interphase chemistry that is mainly composed of organic long-chain polyether and inorganic lithium sulfite. The long-chain polyether possesses flexibility endowing the interphase with robustness, while its combination with inorganic lithium sulfite accelerates lithium intercalation/deintercalation kinetics via decreasing the resistance for charge transfer.

8.
Neural Comput Appl ; : 1-10, 2022 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-35228779

RESUMEN

Based on CT and MRI images acquired from normal pressure hydrocephalus (NPH) patients, using machine learning methods, we aim to establish a multimodal and high-performance automatic ventricle segmentation method to achieve an efficient and accurate automatic measurement of the ventricular volume. First, we extract the brain CT and MRI images of 143 definite NPH patients. Second, we manually label the ventricular volume (VV) and intracranial volume (ICV). Then, we use the machine learning method to extract features and establish automatic ventricle segmentation model. Finally, we verify the reliability of the model and achieved automatic measurement of VV and ICV. In CT images, the Dice similarity coefficient (DSC), intraclass correlation coefficient (ICC), Pearson correlation, and Bland-Altman analysis of the automatic and manual segmentation result of the VV were 0.95, 0.99, 0.99, and 4.2 ± 2.6, respectively. The results of ICV were 0.96, 0.99, 0.99, and 6.0 ± 3.8, respectively. The whole process takes 3.4 ± 0.3 s. In MRI images, the DSC, ICC, Pearson correlation, and Bland-Altman analysis of the automatic and manual segmentation result of the VV were 0.94, 0.99, 0.99, and 2.0 ± 0.6, respectively. The results of ICV were 0.93, 0.99, 0.99, and 7.9 ± 3.8, respectively. The whole process took 1.9 ± 0.1 s. We have established a multimodal and high-performance automatic ventricle segmentation method to achieve efficient and accurate automatic measurement of the ventricular volume of NPH patients. This can help clinicians quickly and accurately understand the situation of NPH patient's ventricles.

9.
Artículo en Inglés | MEDLINE | ID: mdl-34769965

RESUMEN

This study aims to analyze whether exposure to indoor air pollution affects obesity. In our research, we recruited 127 participants, with an average age of 43.30 ± 15.38 years old, residing in 60 households. We monitored indoor air quality for 24 h, and conducted both questionnaire surveys and collected serum samples for analysis, to assess the relationship between indoor air pollutant exposure and obesity. After adjusting for demographic characteristics, the results showed that CO2 exposure is positively associated with being overweight and with a higher risk of being abdominally obese. Exposures to CO and formaldehyde were also positively associated with being overweight. IQR increase in TVOC was positively associated with increases in the risk of a high BMI, being abdominally obese and having a high body fat percentage. Two-pollutant models demonstrate that TVOCs presented the strongest risks associated with overweightness. We concluded that persistent exposure to indoor gaseous pollutants increases the risk of overweightness and obesity, as indicated by the positive association with BMI, abdominal obesity, and percentage body fat. TVOCs display the strongest contribution to obesity.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Compuestos Orgánicos Volátiles , Adulto , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Contaminación del Aire , Contaminación del Aire Interior/análisis , Contaminación del Aire Interior/estadística & datos numéricos , Monitoreo del Ambiente , Gases , Humanos , Persona de Mediana Edad , Obesidad/epidemiología , Obesidad/etiología , Material Particulado/análisis , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/toxicidad
10.
Ecotoxicol Environ Saf ; 227: 112937, 2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34717218

RESUMEN

BACKGROUND: The impact of heavy metals on pulmonary function among young adults has been scarcely studied, especially by a longitudinal cohort study. METHODS: We prospectively enrolled 974 young adults (aged 20-45 years) during 2017-2019 and measured pulmonary function and urinary heavy metals, including manganese, copper, chromium, iron, nickel, zinc, cadmium, and lead. Among them, 461 participants had examination of the same urinary heavy metals during 2006-2008, which could be used as a cohort for long-term effect of urinary metals on pulmonary function. RESULTS: In the 974 enrolled participants, urinary heavy metals were within normal range. The urinary manganese level was the only significant factor for the observed/predicted ratios of forced vital capacity (FVC %)(ß coefficient: -1.217, p = 0.030), forced expiratory volume in one second (FEV1%)(ß: -1.664, p < 0.001), and FEV1/FVC% of predicted (ß: -0.598, p = 0.047) in multivariable linear regression under cross sectional design. In cohort analysis, the urinary manganese level was also negatively associated with the FEV1% (ß: -1.920, p = 0.021). There was no significance between other urinary heavy metals and pulmonary function for all participants. The urinary manganese significantly negatively correlated with FVC%, FEV1% and FEV1/FVC% in female subgroup whereas copper and iron were significantly negatively correlated with FVC% in male subgroup. CONCLUSIONS: Among urinary heavy metals, urinary manganese level was associated with pulmonary function negatively, even the level was within normal range. In addition, women might be more susceptible to manganese. There is emergent need to conduct further investigation to confirm the respiratory hazardous effects of manganese.


Asunto(s)
Manganeso , Metales Pesados , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Estudios Longitudinales , Pulmón , Masculino , Manganeso/toxicidad , Metales Pesados/toxicidad , Adulto Joven
12.
Nat Neurosci ; 23(10): 1297-1306, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32895565

RESUMEN

How astrocytes grow and integrate into neural circuits remains poorly defined. Zebrafish are well suited for such investigations, but bona fide astrocytes have not been described in this system. Here we characterize a zebrafish cell type that is remarkably similar to mammalian astrocytes that derive from radial glial cells and elaborate processes to establish their territories at early larval stages. Zebrafish astrocytes associate closely with synapses, tile with one another and express markers, including Glast and glutamine synthetase. Once integrated into circuits, they exhibit whole-cell and microdomain Ca2+ transients, which are sensitive to norepinephrine. Finally, using a cell-specific CRISPR-Cas9 approach, we demonstrate that fgfr3 and fgfr4 are required for vertebrate astrocyte morphogenesis. This work provides the first visualization of astrocyte morphogenesis from stem cell to post-mitotic astrocyte in vivo, identifies a role for Fgf receptors in vertebrate astrocytes and establishes zebrafish as a valuable new model system to study astrocyte biology in vivo.


Asunto(s)
Astrocitos/fisiología , Encéfalo/crecimiento & desarrollo , Células Ependimogliales/fisiología , Morfogénesis , Neuronas/fisiología , Médula Espinal/crecimiento & desarrollo , Pez Cebra/crecimiento & desarrollo , Animales , Señalización del Calcio , Vías Nerviosas/fisiología , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/fisiología , Receptor Tipo 4 de Factor de Crecimiento de Fibroblastos/fisiología , Sinapsis/fisiología , Proteínas de Pez Cebra/fisiología
13.
Animals (Basel) ; 10(2)2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31973127

RESUMEN

The age of onset of sexual maturity is an important reproductive trait in chickens. In this study, we explored candidate genes associated with sexual maturity and ovary development in chickens. We performed DGE RNA-sequencing analyses of ovaries of pre-laying (P-F-O1, L-F-O1) and laying (P-F-O2, L-F-O2) hens of two sub-breeds of Ningdu Yellow chicken. A total of 3197 genes were identified in the two comparisons, and 966 and 1860 genes were detected exclusively in comparisons of P-F-O1 vs. P-F-O2 and L-F-O1 vs. L-F-O2, respectively. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed that genes involved in transmembrane signaling receptor activity, cell adhesion, developmental processes, the neuroactive ligand-receptor interaction pathway, and the calcium signaling pathway were enriched in both comparisons. Genes on these pathways, including growth hormone (GH), integrin subunit beta 3 (ITGB3), thyroid stimulating hormone subunit beta (TSHB), prolactin (PRL), and transforming growth factor beta 3 (TGFB3), play indispensable roles in sexual maturity. As a gene unique to poultry, hen egg protein 21 kDa (HEP21) was chosen as the candidate gene. Differential expression and association analyses were performed. RNA-seq data and qPCR showed that HEP21 was significantly differentially expressed in pre-pubertal and pubertal ovaries. A total of 23 variations were detected in HEP21. Association analyses of single nucleotide polymorphisms (SNPs) in HEP21 and reproductive traits showed that rs315156783 was significantly related to comb height at 84 and 91 days. These results indicate that HEP21 is a candidate gene for sexual maturity in chickens. Our results contribute to a more comprehensive understanding of sexual maturity and reproduction in chickens.

15.
Front Pharmacol ; 10: 104, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30804790

RESUMEN

Background and Objective: Idiopathic central precocious puberty (ICPP) is characterized by early pubertal changes, the acceleration of growth velocity, and rapid bone maturation that often results in reduced adult height. Gonadotrophin-releasing hormone agonist (GnRHa) is currently considered to be an effective therapeutic agent. At present, GnRH stimulation test is adopted as a gold standard for the diagnosis of ICPP and the efficacy evaluation of GnRHa therapy. However, it is difficult to operate in practice due to the cumbersome procedures and multiple blood samples required. This study was conducted to establish the value of pelvic ultrasound in diagnosing ICPP and evaluating the efficacy of GnRHa therapy. Materials and Methods: One hundred and twenty-two girls with ICPP (ICPP group) were enrolled in the study. Pelvic ultrasound and levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were examined before and after GnRHa therapy for 3 months. Eighty normal prepubertal girls were enrolled as the control group. The difference in pelvic ultrasound parameters between the ICPP group before GnRHa therapy and the control group was compared by independent-sample t-test, while paired t-test for ICPP group before and after GnRHa therapy. Receiver operating characteristic (ROC) curve was used to explore the optimal pelvic ultrasound parameters for diagnosing ICPP. Pearson correlation analysis was performed between the pelvic ultrasound parameters and serum sexual hormone level. Results: The pelvic ultrasound parameters (length of the uterine body, anteroposterior diameter of the uterine body, transverse diameter of the uterine body, volume of the uterine body, uterine body-cervix ratio, length of the ovary, transverse diameter of the ovary, anteroposterior diameter of the ovary, volume of the ovary, number of increased follicles and maximum diameter of the follicle) in the ICPP group before GnRHa therapy were significantly larger than those of the control group (P < 0.05). All the above pelvic ultrasound parameters in the ICPP group were significantly decreased after GnRHa therapy compared with those before treatment (P < 0.05). The volume of the uterine body had the largest area under the ROC curve in differentiating between patients with ICCP and the control group. Pelvic ultrasound parameters were significantly correlated with serum sexual hormone levels (P < 0.05). Conclusion: This study indicates pelvic ultrasound is a simple and reliable tool to diagnose ICPP and evaluates the efficacy of GnRHa therapy by dynamically observing the morphology of internal genitalia. The volume of uterine body was the best ultrasound parameter to distinguish patients with ICPP from normal girls.

16.
Front Pharmacol ; 10: 43, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30766486

RESUMEN

Background and Objective: Intussusception is the most frequent pediatric abdominal emergency. Intestinal spasm, ischemia, necrosis and even death may occur without prompt diagnosis and treatment. The ultrasound-guided reduction by saline enema is a preferred non-surgical procedure for intussusception. Muscular relaxants can relieve the intestinal spasm and edema by relaxing the intestinal smooth muscle, which may facilitate the treatment of intussusception. However, controversy persists on whether muscular relaxants are effective in the procedure. Therefore, the purpose of our study was to assess the efficacy of atropine known as a muscular relaxant in ultrasound-guided reduction by saline enema in children with intussusception. Methods: All patients with intussusception diagnosed and treated in our department from July 2016 to February 2018 were included. Four hundred and thirty-seven children were enrolled and randomly divided into two groups: an atropine group and a control group. Intramuscular atropine at a dose of 0.02 mg per kilogram of body weight was administrated 15 min before ultrasound-guided reduction by saline enema in the atropine group. In the control group, the ultrasound-guided reduction was performed without using any muscular relaxants. The success rate, duration of the reduction, volume of saline, maximum intra-rectal pressure and complications were recorded and compared between the two groups. Results: The success rate was 95.9% (212 out of 221) and 94.9% (205 out of 216) in the atropine group and the control group, respectively. No significant difference was observed in the success rate between the two groups (P > 0.05). The duration of reduction was significantly lower in the atropine group than in the control group (P < 0.01). The volume of saline was also significantly lower in the atropine group than in the control group (P < 0.05). The maximum intra-rectal pressure showed no difference between the two groups (P > 0.05). Conclusion: Atropine premedication can facilitate ultrasound-guided reduction by saline enema in children with intussusception, by reducing the duration of reduction and the volume of saline in the procedure.

17.
Dev Cell ; 45(3): 376-391.e5, 2018 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-29738714

RESUMEN

Atypical cadherin Dachsous (Dchs) is a conserved regulator of planar cell polarity, morphogenesis, and tissue growth during animal development. Dchs functions in part by regulating microtubules by unknown molecular mechanisms. Here we show that maternal zygotic (MZ) dchs1b zebrafish mutants exhibit cleavage furrow progression defects and impaired midzone microtubule assembly associated with decreased microtubule turnover. Mechanistically, Dchs1b interacts via a conserved motif in its intracellular domain with the tetratricopeptide motifs of Ttc28 and regulates its subcellular distribution. Excess Ttc28 impairs cleavages and decreases microtubule turnover, while ttc28 inactivation increases turnover. Moreover, ttc28 deficiency in dchs1b mutants suppresses the microtubule dynamics and midzone microtubule assembly defects. Dchs1b also binds to Aurora B, a known regulator of cleavages and microtubules. Embryonic cleavages in MZdchs1b mutants exhibit increased, and in MZttc28 mutants decreased, sensitivity to Aurora B inhibition. Thus, Dchs1b regulates microtubule dynamics and embryonic cleavages by interacting with Ttc28 and Aurora B.


Asunto(s)
Aurora Quinasa B/metabolismo , Cadherinas/metabolismo , Embrión no Mamífero/citología , Desarrollo Embrionario/fisiología , Microtúbulos/fisiología , Proteínas de Pez Cebra/metabolismo , Pez Cebra/embriología , Animales , Aurora Quinasa B/genética , Cadherinas/genética , Embrión no Mamífero/metabolismo , Mitosis/fisiología , Huso Acromático/fisiología , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética
18.
J Nanosci Nanotechnol ; 18(1): 318-322, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29768847

RESUMEN

Conductive films have attracted much attention in the printed electronics industry. To date, expensive conductive silver inks have been utilized widely in these conductive films, which ultimately increase the cost. Hence the alternative low-cost copper inks will be of great interest in the future. This paper will present how to synthesize antioxidative conductive copper inks with superior adhesion to FR4 substrates. The antioxidative conductive copper inks were prepared by dispersing the antioxidative copper nanoparticles in diethylene glycol with the bisphenol-F type BEF170 epoxy resin as a binder and the Methyl-5-norbornene-2,3-dicarboxylic anhydride (NMA) as a curing agent, then were coated on FR4 substrates to form the copper films, followed by sintering at 250 °C in nitrogen atmosphere for 20 minutes. We found that the formation of three-dimensional structure between BFE170 binder and curing agent NMA don't affect the conductivities of copper films, and meanwhile can enhance the adhesion strength on FR4 substrates. The lowest resistivity of 158 µΩ · cm determined by using the four-point probe method and the highest adhesion of no peeling after the 10 times peel-off test with 3 M Scotch 600 tape were achieved with the copper ink composed of 1 wt% of BEF170 epoxy resin binder mixed with curing agent NMA in an equivalent ratio of 1:1.

19.
Dev Biol ; 430(2): 385-396, 2017 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-28322738

RESUMEN

Intracellular Ca2+ signaling regulates cellular activities during embryogenesis and in adult organisms. We generated stable Tg[ßactin2:GCaMP6s]stl351 and Tg[ubi:GCaMP6s]stl352 transgenic lines that combine the ubiquitously-expressed Ca2+ indicator GCaMP6s with the transparent characteristics of zebrafish embryos to achieve superior in vivo Ca2+ imaging. Using the Tg[ßactin2:GCaMP6s]stl351 line featuring strong GCaMP6s expression from cleavage through gastrula stages, we detected higher frequency of Ca2+ transients in the superficial blastomeres during the blastula stages preceding the midblastula transition. Additionally, GCaMP6s also revealed that dorsal-biased Ca2+ signaling that follows the midblastula transition persisted longer during gastrulation, compared with earlier studies. We observed that dorsal-biased Ca2+ signaling is diminished in ventralized ichabod/ß-catenin2 mutant embryos and ectopically induced in embryos dorsalized by excess ß-catenin. During gastrulation, we directly visualized Ca2+ signaling in the dorsal forerunner cells, which form in a Nodal signaling dependent manner and later give rise to the laterality organ. We found that excess Nodal increases the number and the duration of Ca2+ transients specifically in the dorsal forerunner cells. The GCaMP6s transgenic lines described here enable unprecedented visualization of dynamic Ca2+ events from embryogenesis through adulthood, augmenting the zebrafish toolbox.


Asunto(s)
Blastómeros/metabolismo , Señalización del Calcio/fisiología , Calcio/análisis , Proteínas Recombinantes de Fusión/análisis , Pez Cebra/embriología , Actinas/genética , Animales , Animales Modificados Genéticamente , Blastómeros/química , Blastómeros/ultraestructura , Blástula/química , Blástula/ultraestructura , Tipificación del Cuerpo , Calmodulina/genética , Embrión no Mamífero/química , Embrión no Mamífero/metabolismo , Embrión no Mamífero/ultraestructura , Genes Reporteros , Proteínas Fluorescentes Verdes/análisis , Proteínas Fluorescentes Verdes/genética , Fragmentos de Péptidos/genética , Péptidos/genética , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Ubiquitina/genética
20.
J Occup Environ Hyg ; 13(10): 802-15, 2016 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-27104797

RESUMEN

A desktop fume hood installed with an innovative design of flow boundary-layer separation controllers on the leading edges of the side plates, work surface, and corners was developed and characterized for its flow and containment leakage characteristics. The geometric features of the developed desktop fume hood included a rearward offset suction slot, two side plates, two side-plate boundary-layer separation controllers on the leading edges of the side plates, a slanted surface on the leading edge of the work surface, and two small triangular plates on the upper left and right corners of the hood face. The flow characteristics were examined using the laser-assisted smoke flow visualization technique. The containment leakages were measured by the tracer gas (sulphur hexafluoride) detection method on the hood face plane with a mannequin installed in front of the hood. The results of flow visualization showed that the smoke dispersions induced by the boundary-layer separations on the leading edges of the side plates and work surface, as well as the three-dimensional complex flows on the upper-left and -right corners of the hood face, were effectively alleviated by the boundary-layer separation controllers. The results of the tracer gas detection method with a mannequin standing in front of the hood showed that the leakage levels were negligibly small (≤0.003 ppm) at low face velocities (≥0.19 m/s).


Asunto(s)
Movimientos del Aire , Contaminación del Aire Interior/prevención & control , Exposición Profesional/prevención & control , Diseño de Equipo , Maniquíes , Ventilación/instrumentación
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