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1.
Nature ; 581(7808): 303-309, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32214235

RESUMEN

Single-cell analysis is a valuable tool for dissecting cellular heterogeneity in complex systems1. However, a comprehensive single-cell atlas has not been achieved for humans. Here we use single-cell mRNA sequencing to determine the cell-type composition of all major human organs and construct a scheme for the human cell landscape (HCL). We have uncovered a single-cell hierarchy for many tissues that have not been well characterized. We established a 'single-cell HCL analysis' pipeline that helps to define human cell identity. Finally, we performed a single-cell comparative analysis of landscapes from human and mouse to identify conserved genetic networks. We found that stem and progenitor cells exhibit strong transcriptomic stochasticity, whereas differentiated cells are more distinct. Our results provide a useful resource for the study of human biology.


Asunto(s)
Células/citología , Células/metabolismo , Análisis de la Célula Individual/métodos , Adulto , Animales , Pueblo Asiatico , Diferenciación Celular , Línea Celular , Separación Celular , China , Bases de Datos Factuales , Cuerpos Embrioides/citología , Cuerpos Embrioides/metabolismo , Etnicidad , Feto/citología , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Humanos , Inmunidad , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Ratones , Especificidad de Órganos , ARN Mensajero/análisis , ARN Mensajero/genética , Análisis de Secuencia de ARN , Análisis de la Célula Individual/instrumentación , Procesos Estocásticos
2.
Water Sci Technol ; 89(5): 1401-1417, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38483505

RESUMEN

In this study, the mesoporous material NCNT was prepared by treating carbon nanotubes (CNT) with hydrazine and subsequently loaded with Cu-Fe layered double hydroxide (CuFeLDH) to create a multiphase catalyst (CuFeLDH-NCNT). Its application as a multiphase catalyst was investigated in an ultrasound-assisted Fenton process for ciprofloxacin (CIP) degradation in aqueous solution. In addition, the impacts of catalyst dosage, ultrasonic power, H2O2 dosage, and beginning pH on CIP removal efficiency were carefully evaluated to maximize the removal efficiency of CIP. The findings indicated that the elimination rate of the initial CIP concentration of 20 mg/L surpassed 94.66% after a mere 100 min, while the TOC degradation rate was 70.4%. The high removal rate was due to the synergistic action between the nanoparticles, H2O2, and ultrasonography. The degradation intermediates of CIP were examined, and putative degradation pathways and mechanisms were postulated.


Asunto(s)
Peróxido de Hidrógeno , Nanotubos de Carbono , Ultrasonografía , Ciprofloxacina , Hidróxidos
3.
Water Sci Technol ; 86(11): 2999-3013, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36515202

RESUMEN

A composite catalyst nZVI/Co/N-CNT was prepared by loading nano-zero-valent iron-cobalt bimetals on porous materials (N-CNT) by a liquid-phase reduction method. Transmission electron microscopy (TEM), X-ray diffraction (XRD) and the X-ray electron spectroscopy (XPS) characterization method were used to characterize and analyze the structure of the prepared samples. The effects of different factors on the removal of levofloxacin (LOF) by the nZVI/Co/N-CNT activated persulfate (PMS) system were compared. The results show that the removal rate of LOF can reach 98.14% when the LOF concentration is 20 mg/L, the iron-cobalt molar ratio is 5:1, the dosage of nZVI/Co/N-CNT is 0.3 g·L-1, and the dosage of PMS is 0.2 g·L-1 and pH = 7. Free radical quenching experiments showed that SO4-· and ·OH coexisted during the reaction, and ·OH was the main active species, and the possible removal mechanism of LOF was speculated.


Asunto(s)
Levofloxacino , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/química , Hierro/química , Catálisis , Cobalto
4.
Sensors (Basel) ; 21(16)2021 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-34450789

RESUMEN

In this paper, we present a fully integrated Non-dispersive Infrared (NDIR) CO2 sensor implemented on a silicon chip. The sensor is based on an integrating cylinder with access waveguides. A mid-IR LED is used as the optical source, and two mid-IR photodiodes are used as detectors. The fully integrated sensor is formed by wafer bonding of two silicon substrates. The fabricated sensor was evaluated by performing a CO2 concentration measurement, showing a limit of detection of ∼750 ppm. The cross-sensitivity of the sensor to water vapor was studied both experimentally and numerically. No notable water interference was observed in the experimental characterizations. Numerical simulations showed that the transmission change induced by water vapor absorption is much smaller than the detection limit of the sensor. A qualitative analysis on the long term stability of the sensor revealed that the long term stability of the sensor is subject to the temperature fluctuations in the laboratory. The use of relatively cheap LED and photodiodes bare chips, together with the wafer-level fabrication process of the sensor provides the potential for a low cost, highly miniaturized NDIR CO2 sensor.


Asunto(s)
Dióxido de Carbono , Silicio
5.
Med Sci Monit ; 25: 4202-4206, 2019 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-31168048

RESUMEN

BACKGROUND To study the clinical effective of emergency cervical cerclage (ECC) in pregnant women who have cervical insufficiency with prolapsed membranes. MATERIAL AND METHODS This study was devised as a retrospective cohort in a single medical center, in which we collected clinical data from patient records. Inclusion criteria were: physical examination indicated ECC was performed at 15 to 25 gestational weeks at the Sixth Medical Center of the PLA General Hospital, and singleton pregnancy. The collected clinical data included: duration of pregnancy at delivery, interval between ECC and delivery, neonatal weight, neonatal mortality, neonatal morbidity, and Neonatal Intensive Care Unit (NICU) admission. RESULTS We included 50 women with singleton pregnancies. No surgical complications occurred in any patients. The gestational age at cerclage was 21.3±2.2 weeks. No patients had membrane damage due to surgery. No surgical complications were reported. Five (10%) patients underwent chorioamnionitis. The time interval between ECC and delivery was 11.2±7.1 weeks. The mean gestational age at delivery was 34.1 weeks. The rate of vaginal delivery was 96%. Ten patients had pregnancy lasting longer than 36 weeks. The mean neonate delivery weight was 2510.7 g. Twenty neonates were admitted to the Neonatal Intensive Care Unit (NICU), and the mean NICU stay was 21 days. CONCLUSIONS ECC has good perinatal results. Our results provide clinical evidence for the efficacy and risks of ECC.


Asunto(s)
Cerclaje Cervical/mortalidad , Resultado del Embarazo/epidemiología , Cerclaje Cervical/efectos adversos , Cerclaje Cervical/métodos , Cuello del Útero/cirugía , China , Urgencias Médicas , Femenino , Rotura Prematura de Membranas Fetales/cirugía , Edad Gestacional , Humanos , Recién Nacido , Muerte Perinatal/etiología , Mortalidad Perinatal/tendencias , Embarazo , Nacimiento Prematuro/etiología , Estudios Retrospectivos , Suturas , Incompetencia del Cuello del Útero/cirugía , Prolapso Uterino/complicaciones
6.
Sensors (Basel) ; 19(19)2019 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-31575053

RESUMEN

In this paper, we propose a novel, miniaturized non-dispersive infrared (NDIR) CO2 sensor implemented on a silicon chip. The sensor has a simple structure, consisting of a hollow metallic cylindrical cavity along with access waveguides. A detailed analysis of the proposed sensor is presented. Simulation with 3D ray tracing shows that an integrating cylinder with 4 mm diameter gives an equivalent optical path length of 3 . 5 cm. The sensor is fabricated using Deep Reactive Ion Etching (DRIE) and wafer bonding. The fabricated sensor was evaluated by performing a CO2 concentration measurement, showing a limit of detection of ∼100 ppm. The response time of the sensor is only ∼2.8 s, due to its small footprint. The use of DRIE-based waveguide structures enables mass fabrication, as well as the potential co-integration of flip-chip integrated midIR light-emitting diodes (LEDs) and photodetectors, resulting in a compact, low-power, and low-cost NDIR CO2 sensor.

7.
Water Sci Technol ; 79(10): 1878-1886, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31294704

RESUMEN

In this study, an ordered mesoporous silica modified with lanthanum oxide was synthesized using diatomite as silica source and applied for adsorption of phosphate from aqueous solution. By taking cost-effectiveness for practical application into consideration, the adsorbent with a theoretical La/SiO2 molar ratio of 0.2 (La0.2M41) possessed a promising performance. In the batch adsorption tests, the adsorbents with La2O3 loading possessed markedly enhanced adsorption capacities. Phosphate uptake by La0.2M41 was pH-dependent with the highest sorption capacities observed over a pH range of 3.0-6.0. Coexistent anions displayed an adverse effect on phosphate adsorption following the order of CO3 2-  > F-  > NO3 - > Cl- > SO4 2-. In the kinetic study, phosphate adsorption onto La0.2M41 followed the pseudo-second-order equation better than the pseudo-first-order, suggesting chemisorption. The Langmuir isothermal model well described the adsorption isotherm data, showing a maximum adsorption capacity for phosphate of up to 263.16 mg/g at 298 K. In a real treated wastewater effluent with phosphate concentration of 2.5 mg P/L, La0.2M41 efficiently reduced the phosphate concentration to 28 µg P/L.


Asunto(s)
Tierra de Diatomeas/química , Fosfatos , Dióxido de Silicio , Lantano , Óxidos
8.
Opt Express ; 24(19): 21541-50, 2016 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-27661892

RESUMEN

We report on efficient optical beam-steering using a hot-embossed reflective blazed grating in combination with liquid crystal. A numerical simulation of the electrical switching characteristics of the liquid crystal is performed and the results are used in an FDTD optical simulator to analyze the beam deflection. The corresponding experiment on the realized device is performed and is found to be in good agreement. Beam deflection angles of 4.4° upon perpendicular incidence are found with low applied voltages of 3.4 V. By tilting the device with respect to the incoming optical beam it can be electronically switched such that the beam undergoes either total internal reflection or reflection with a tunable angle.

9.
Chin Med Sci J ; 29(1): 63-4, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24698684

RESUMEN

ABNORMALITIES during pregnancy are regarded as pathological pregnancy. Early detection of anomalies is urgent to take measures as soon as possible to prevent serious pregnancy complications. Procoagulant-anticoagulant imbalance is often the pathological basis of many pathological pregnancy conditions, leading to a hypercoagulable state. We compared the thromboelastographic parameters between pathological pregnancy and normal pregnancy patients, evaluated the value of thromboelastography in early detecting pathological pregnancy and predicting postpartum hemorrhage.


Asunto(s)
Diabetes Gestacional/sangre , Preeclampsia/sangre , Complicaciones Hematológicas del Embarazo/sangre , Tromboelastografía/métodos , Trombosis de la Vena/sangre , Femenino , Humanos , Hemorragia Posparto/sangre , Hemorragia Posparto/prevención & control , Embarazo
10.
Water Sci Technol ; 68(12): 2613-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24355848

RESUMEN

In order to improve the TN removal efficiency on low carbon-to-nitrogen micro-polluted water, in this study, a layered biological aerated filter (L-BAF) was built. The results showed that the removal efficiency for CODMn, NH3-N, and TN was 71.6-90.3%, 99.8-99.9%, and 57.8-65.7%, respectively, when the C/N ratio was kept at 3 and the volumetric flow rate was 0.072 m(3) d(-1). The L-BAF could improve the TN removal efficiency by about 20% compared to a traditional process. The L-BAF and traditional process removal efficiency for NH3-N and CODMn were similar. The kinetic performance of the L-BAF indicated that the relationship of CODMn removal efficiency with the influent CODMn concentration could be described by ln(C/C0) = -(0.0023/Q0C0(0.9398))H.


Asunto(s)
Reactores Biológicos/microbiología , Carbono/aislamiento & purificación , Nitrógeno/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/instrumentación , Purificación del Agua/métodos , Biodegradación Ambiental , Biopelículas/crecimiento & desarrollo , Análisis de la Demanda Biológica de Oxígeno , Cerámica/química , Filtración , Cinética , Oxígeno/análisis , Poliuretanos/química , Porosidad
11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 30(4): 737-42, 2013 Aug.
Artículo en Zh | MEDLINE | ID: mdl-24059047

RESUMEN

This study designed an audio signal acquisition system to achieve real-time detection of R peak for heart rate variability (HRV) analysis, substituting ECG-specific data acquisition board with sound card. It is proved that the R peak with low frequency can be gathered by sound card. The comparison with PowerLab signal acquisition system has shown that the acquisition system of R peak could accurately detect the R peak. The R peak detected by sound card and PowerLab signal acquisition system completely overlap each other, while RR intervals has no difference. The HRV analysis was accurate and reliable with the RR interval from sound card. This low cost, high performance, strong compatibility and easy upgraded acquisition system of R peak compared with the traditional data acquisition board has the value of practical uses and might have broad applications in the future.


Asunto(s)
Electrocardiografía/métodos , Frecuencia Cardíaca/fisiología , Monitoreo Fisiológico/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Sonido , Algoritmos , Humanos
12.
Nat Commun ; 14(1): 4924, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37582782

RESUMEN

Thermal homeostasis is vital for mammals and is controlled by brain neurocircuits. Yet, the neural pathways responsible for cold defense regulation are still unclear. Here, we found that a pathway from the lateral parabrachial nucleus (LPB) to the dorsomedial hypothalamus (DMH), which runs parallel to the canonical LPB to preoptic area (POA) pathway, is also crucial for cold defense. Together, these pathways make an equivalent and cumulative contribution, forming a parallel circuit. Specifically, activation of the LPB → DMH pathway induced strong cold-defense responses, including increases in thermogenesis of brown adipose tissue (BAT), muscle shivering, heart rate, and locomotion. Further, we identified somatostatin neurons in the LPB that target DMH to promote BAT thermogenesis. Therefore, we reveal a parallel circuit governing cold defense in mice, which enables resilience to hypothermia and provides a scalable and robust network in heat production, reshaping our understanding of neural circuit regulation of homeostatic behaviors.


Asunto(s)
Hipotermia , Termogénesis , Ratones , Animales , Termogénesis/fisiología , Área Preóptica/metabolismo , Vías Nerviosas/fisiología , Homeostasis , Hipotermia/metabolismo , Tejido Adiposo Pardo/metabolismo , Frío , Mamíferos
13.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 28(3): 597-601, 606, 2011 Jun.
Artículo en Zh | MEDLINE | ID: mdl-21774231

RESUMEN

This study designed one index of HRV from Poincaré plot named 5SSD1 by the present authors, which can describe the characteristics of the heart rate dynamics with 5-second data. We also investigated the feasibility of its clinical application in real-time monitoring of the activity of autonomic nervous system. We studied 20 patients scheduled for oral maxillofacial surgery. ECG recording was obtained when kept awake and anesthetic states, respectively. We calculated the correlation coefficients between the 5SSD1 and the other quantitative indicators, such as 5-minute HRV in the time domain, the frequency domain, and the Poincaré plot families. The correlation between 5SSD1 and indicators, such as rMSSD, HF and SD1 of 5-minute HRV was significantly high, with r=0.995, 0.895, 0.996, respectively, at P<0.01 for all. However, the correlation between 5SSD1 and the other indicators of 5-minute HRV was relatively poor. It was proved that 5SSD1 could be used to assess the activities of the autonomic nervous system in real-time, and the stable and reliable results might play more roles in the clinical applications.


Asunto(s)
Sistema Nervioso Autónomo/fisiología , Electrocardiografía/métodos , Frecuencia Cardíaca/fisiología , Procesamiento de Señales Asistido por Computador , Adolescente , Adulto , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
14.
Sci China Life Sci ; 64(6): 911-925, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33068286

RESUMEN

Major depressive disorder (MDD) is a prevalent psychiatric disease that involves malfunctions of different cell types in the brain. Accumulating studies started to reveal that microglia, the primary resident immune cells, play an important role in the development and progression of depression. Microglia respond to stress-triggered neuroinflammation, and through the release of proinflammatory cytokines and their metabolic products, microglia may modulate the function of neurons and astrocytes to regulate depression. In this review, we focused on the role of microglia in the etiology of depression. We discussed the dynamic states of microglia; the correlative and causal evidence of microglial abnormalities in depression; possible mechanisms of how microglia sense depression-related stress and modulate depression state; and how antidepressive therapies affect microglia. Understanding the role of microglia in depression may shed light on developing new treatment strategies to fight against this devastating mental illness.


Asunto(s)
Antidepresivos/uso terapéutico , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/patología , Microglía/efectos de los fármacos , Microglía/patología , Animales , Humanos
15.
Sci Adv ; 6(36)2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32917598

RESUMEN

Heat defense is crucial for survival and fitness. Transmission of thermosensory signals into hypothalamic thermoregulation centers represents a key layer of regulation in heat defense. Yet, how these signals are transmitted into the hypothalamus remains poorly understood. Here, we reveal that lateral parabrachial nucleus (LPB) glutamatergic prodynorphin and cholecystokinin neuron populations are progressively recruited to defend elevated body temperature. These two nonoverlapping neuron types form circuits with downstream preoptic hypothalamic neurons to inhibit the thermogenesis of brown adipose tissues (BATs) and activate tail vasodilation, respectively. Both circuits are activated by warmth and can limit fever development. The prodynorphin circuit is further required for regulating energy expenditure and body weight homeostasis. Thus, these findings establish that the genetic and functional specificity of heat defense neurons occurs as early as in the LPB and uncover categorical neuron types for encoding two heat defense variables, inhibition of BAT thermogenesis and activation of vasodilation.

16.
Data Brief ; 25: 104126, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31294065

RESUMEN

The data presented in this article describe characteristics of the polysaccharides, designated as CM1 and CMS, isolated from the fruiting body of C. militaris. Fourier transform infrared spectrometry analysis was used to identify the basic characteristics of the polysaccharides and the completeness of methylation. Gas chromatography-tandem mass spectrometry and nuclear magnetic resonance spectroscopy were carried out to reveal the glycosidic linkages of CM1 and CMS. Further interpretation and discussion could be found at our research article entitled "Structural characterisation and cholesterol efflux improving capacity of the novel polysaccharides from Cordyceps militaris" (Hu et al., 2019; https://doi.org/10.1016/j.ijbiomac.2019.03.078) [1].

17.
Nat Neurosci ; 22(6): 921-932, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31127258

RESUMEN

The neural substrates for predatory hunting, an evolutionarily conserved appetitive behavior, remain largely undefined. Photoactivation of zona incerta (ZI) GABAergic neurons strongly promotes hunting of both live and artificial prey. Conversely, photoinhibition of these neurons or deletion of their GABA function severely impairs hunting. Here electrophysiological recordings reveal that ZI neurons integrate prey-related multisensory signals and discriminate prey from non-prey targets. Visual or whisker sensory deprivation reduces calcium responses induced by prey introduction and attack and impair hunting. ZI photoactivation largely corrects the hunting impairment caused by sensory deprivations. Motivational and reinforcing assays reveal that ZI photoactivation is associated with a strong appetitive drive, causing repetitive self-stimulatory behaviors. These ZI neurons project to the periaqueductal gray matter to induce hunting and motivation. Thus, we have delineated the function of ZI GABAergic neurons in hunting, which integrates prey-related sensory signals into prey detection and attack and induces a strong appetitive motivational drive.


Asunto(s)
Neuronas GABAérgicas/fisiología , Conducta Predatoria/fisiología , Zona Incerta/fisiología , Animales , Ratones
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