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1.
Artigo em Inglês | MEDLINE | ID: mdl-32359089

RESUMO

All-inorganic lead halide perovskites with potential stability improvement is promising candidate for optoelectronic applications. However, fundamental questions remain over the component interaction in the perovskite precursor solution due to the limitation of the most commonly used solvents of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). Here, we report a simple and very effective interaction tailoring strategy for all-inorganic CsPbI3-xBrx perovskites by involving ionic liquid solvent methylammonium acetate (MAAc). We found that C=O has strong interaction with lead (Pb2+) and the N-H…I hydrogen bonds formation are observed. The interaction enables the stable perovskite precursor solution and allows the high-quality production of pinhole-free, large grain size, and flat all-inorganic perovskite films by retarding the crystallization. With a one-step, without the necessity for antisolvent treatment, air-processing approach regardless of humidity, the corresponding photovoltaic cell exhibits a high efficiency of 17.10% along with long operation stability over 1500 h under continuous light illumination.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32433812

RESUMO

Two-dimensional (2D) AA'n-1MnX3n+1 type halide perovskites incorporating straight chain symmetric diammonium cations define a new type of structure that holds potential of both highly efficient charge transport and high environmental stability. Unfortunately, their optoelectronic properties are largely unexplored and there is lack of high quality single crystals in large dimension for practical application. Here, we ventured into synthesizing centimeter-sized AA'n-1MnX3n+1 type perovskite BDAPbI4 (BDA = NH3C4H8NH3) single crystal and reported its charge transport properties under X-ray excitation. The crystals were grown via a modified temperature crystallization method. It is found that the crystal shows a staggered configuration of the [PbI6]4- layers, a bandgap of 2.37 eV and a low trap density of 3.1 × 109 cm-3. The single crystal X-ray detector exhibits an excellent sensitivity of 242 µC Gyair-1 cm-2 under the 10 V bias (0.31 V µm-1), a detection limit as low as 430 nGyair s-1, ultra-stable response current, a stable baseline with the lowest dark current drift of 6.06 ×10-9 nA cm-1 s-1 V-1, and rapid response time of τrise = 7.3 ms and τfall = 22.5 ms. The effective synthesis method and excellent charge transport properties of AA'n-1MnX3n+1 type 2D perovskite single crystals make them promising candidates for the next generation of optoelectronic devices.

3.
Soft Robot ; 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32319857

RESUMO

Grasping is an important characteristic of robots in interacting with humans and the environment. Due to the inherent compliance of soft grippers, they can easily adapt to novel objects and operate safely in a human-centered environment. However, soft hands suffer from poor grasping robustness and operation durability, especially for heavy objects or objects with sharp spikes, mainly due to their fragile material and low structural stiffness of the soft actuators. Thus, the widespread use of soft hands in daily applications is still limited. Existing works have shown a promising direction to enhance grasping performance by solving the contradiction between inherent compliance/adaptability and loading capacity. It is known that the stiffness of the robotic phalange is highly related to the performance of robotic hands. In this article, we propose a novel variable stiffness particle phalange, called VSPP here. The proposed VSPP exhibits variable stiffness characteristics without the need for dedicated actuation by utilizing passive particle jamming resulted from forces in interacting with the environment. The VSPP can cooperate with any kind of actuators, soft or rigid, to function as a compliant and robust robotic hand. A prototype robotic hand based on VSPP could maintain reliable grasping even when pierced by sharp objects such as a needle, a cactus, and a durian. This durability is effective both in air and underwater, thus presents new possibilities for the soft robotic hand to work in a harsh environment. The inherent multidirectional compliance of the VSPP makes safety in human/robot interaction guaranteed. The design and modeling presented in this research will provide useful guidance in VSPP applications. A prototype gripper, VSPP-3, composed of three 2-segments VSPP fingers and pneumatic joints, has been built for demonstrations in reliable and robust grasping of daily objects. The sample grasping has shown that the proposed VSPP has great potential for a robust and durable soft robotic hand or gripper design.

4.
Ecotoxicol Environ Saf ; 196: 110538, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32244118

RESUMO

The use of phytoremediation was an efficient strategy for the restoration of mine slag and the addition of modifier was favorable for improving the phytoremediation efficiency. Herein, spent mushroom compost (SMC) was added in manganese (Mn) slag to reveal the phytoremediation potential of Paulownia fortunei seedlings. The transportation, subcellular distribution and chemical forms of Mn in P. fortunei, the diurnal variation of photosynthesis and antioxidant enzyme activities in P. fortunei leaves were measured to reveal the effect of SMC (mass ratios of 10%, M+) on the phytoremediation of Mn slag. Results showed that the addition of SMC increased the accumulation content of Mn by 408.54% due to the increased biomass of P. fortunei seedlings. After SMC amendment, the maximum net photosynthetic rate (Pn) increased and the superoxide dismutase (SOD) activities decreased significantly (p < 0.05), which was beneficial to the tolerance of leaves to Mn stress. SMC amendment maintained the cell structural integrity of P. fortunei seedlings observed by transmission electron microscope (TEM). Additionally, SMC amendment decreased the damage level of Mn to the cell of P. fortunei seedlings by using function groups (-CH3 and -COOH) to bond Mn in the cell walls and vacuoles. SMC amendment reduced the Mn toxicity to P. fortunei seedlings and improved the phytoremediation capacity.

5.
Soft Robot ; 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32320346

RESUMO

Fluid actuated soft robots, or fluidic elastomer actuators, have shown great potential in robotic applications where large compliance and safe interaction are dominant concerns. They have been widely studied in wearable robotics, prosthetics, and rehabilitations in recent years. However, such soft robots and actuators are tethered to a bulky pump and controlled by various valves, limiting their applications to a small confined space. In this study, we report a new and effective approach to fluidic power actuation that is untethered, easy to design, fabricate, control, and allows various modes of actuation. In the proposed approach, a sealed elastic tube filled with fluid (gas or liquid) is segmented by adaptors. When twisting a segment, two major effects could be observed: (1) the twisted segment exhibits a contraction force and (2) other segments inflate or deform according to their constraint patterns. Utilizing such effects, various actuation modes could be realized. In this research, four modes of actuation are illustrated: (1) soft actuator and pump actuation, (2) serial actuation, (3) parallel actuation, and (4) agonist and antagonist actuation. Theoretic analysis and experimental studies for the basic actuation principle have been conducted. A case study on an anthropomorphic forearm based on the proposed twisting tube actuation has been developed to showcase the effectiveness of the actuation modes. The studies suggest that the proposed approach has a great potential in both soft and compliant robotics.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32148014

RESUMO

The rapidly growing demand for fast information storage and processing has driven the development of resistive random access memories (RRAMs). Recently, RRAMs based on organometal halide perovskite materials have been reported to have promising memory properties, which are essential for next-generation memory devices. In this study, a hybrid two-dimensional/three-dimensional (2D/3D) perovskite heterostructure has been created by depositing n-butylammonium iodide on top of the CH3NH3PbI3-xClx (MAPbI3-xClx) surface. The perovskite film is fabricated by a facile one-step spin-coating method with room-temperature molten salt methylammonium acetate in the air. Resistive switching memory devices with a 2D/3D perovskite heterostructure exhibit a significantly improved switching window (ON/OFF ratio over 103) with a lower operation voltage compared with their 3D counterparts. The 2D/3D perovskite heterostructure is advantageous for fabricating uniform-crystalline-grain, highly compact structures and can passivate defect states for the MAPbI3-xClx film and the interface, which results in improved memory properties. These results provide a new perspective for developing high-performance perovskite-based memory devices.

8.
Medicine (Baltimore) ; 99(8): e19327, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32080152

RESUMO

The optimal number of examined lymph nodes (ELN) for staging and impact of nodal status on survival following total pancreatectomy (TP) for pancreatic ductal adenocarcinoma (PDAC) is unclear. The aim of this study was to evaluate the prognostic impact of different lymph node status after TP for PDAC.The Surveillance, Epidemiology, and End Results (SEER) database was used to identify patients who underwent TP for PDAC from 2004 to 2015. We calculated overall survival (OS) of these patients using Kaplan-Meier analysis and Cox proportional hazards model.Overall, 1291 patients were included in the study, with 869 node-positive patients (49.5%). A cut-off points analysis revealed that 19, 19, and 13 lymph nodes best discriminated OS for all patients, node-negative patients, and node-positive patients, respectively. Higher number of ELN than the corresponding cut-off points was an independent predictor for better prognosis [all patients: hazard ratios (HR) 0.786, P = .002; node-negative patients: HR 0.714, P = .043; node-positive patients: HR 0.678, P < .001]. For node-positive patients, 1 to 3 positive lymph nodes (PLN) correlated independently with better survival compared with those with 4 or more PLN (HR 1.433, P = .002). Moreover, when analyzed in node-positive patients with less than 13 ELN, neither the number of PLN nor lymph node ratio (LNR) was associated with survival. However, when limited node-positive patients with at least 13 ELN, univariate analyses showed that both the number of PLN and LNR were associated with survival, whereas multivariate analyses demonstrated that only number of PLN was consistently associated with survival (HR 1.556, P = .004).Evaluation at least 19 lymph nodes should be considered as quality metric of surgery in patients who underwent TP for PDAC. For node-negative patients, a minimal number of 19 lymph nodes is adequate to avoid stage migration. For node-positive patients, PLN is superior to LNR in predicting survival after TP, predominantly for those with high number of ELN.


Assuntos
Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/cirurgia , Metástase Linfática , Pancreatectomia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/cirurgia , Idoso , Carcinoma Ductal Pancreático/patologia , Feminino , Humanos , Linfonodos/patologia , Masculino , Neoplasias Pancreáticas/patologia , Prognóstico , Programa de SEER , Estados Unidos/epidemiologia
9.
Int J Phytoremediation ; 22(7): 679-686, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32107924

RESUMO

Effect of polyculture of woody and herbaceous plant with different ecological niche in constructed wetlands (CWs) on wastewater treatment is unclear. Herein, three kinds of polyculture CWs were constructed to treat domestic wastewater: woody polyculture system (W, Nerium and Hibiscus), herbaceous polyculture system (H, Acorus and Typha), woody and herbaceous polyculture system (WH, Nerium, Hibiscus, Acorus and Typha) and non-planted system (N) as control. The seasonality removal performance of pollutant, activities of urease and phosphatase, microscopic characteristics of roots were measured. Results showed that the average removals of COD, TN and TP in WH were significantly higher than that in the other systems. Interspecies competition existed in WH system, while the difference in terms of biomass gradually diminished. Furthermore, the root lengths, area, volume and tip number were higher compared to the other systems. The correlation between the removal rate of TP and activity of phosphatase in upper and bottom layer of CWs showed the opposite tendency, the distribution of plant roots in polyculture essentially impact TP removal rate in CWs. Our results provide the necessary insights for appropriately selecting different plant types for doing polyculture in CWs.


Assuntos
Typhaceae , Águas Residuárias , Biodegradação Ambiental , Nitrogênio , Eliminação de Resíduos Líquidos , Áreas Alagadas
10.
Adv Mater ; 32(14): e1905578, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32101356

RESUMO

The rate-determining process for electrochemical energy storage is largely determined by ion transport occurring in the electrode materials. Apart from decreasing the distance of ion diffusion, the enhancement of ionic mobility is crucial for ion transport. Here, a localized electron enhanced ion transport mechanism to promote ion mobility for ultrafast energy storage is proposed. Theoretical calculations and analysis reveal that highly localized electrons can be induced by intrinsic defects, and the migration barrier of ions can be obviously reduced. Consistently, experiment results reveal that this mechanism leads to an enhancement of Li/Na ion diffusivity by two orders of magnitude. At high mass loading of 10 mg cm-2 and high rate of 10C, a reversible energy storage capacity up to 190 mAh g-1 is achieved, which is ten times greater than achievable by commercial crystals with comparable dimensions.

11.
Adv Mater ; 32(4): e1906374, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31799762

RESUMO

An efficient electron transport layer (ETL) plays a key role in promoting carrier separation and electron extraction in planar perovskite solar cells (PSCs). An effective composite ETL is fabricated using carboxylic-acid- and hydroxyl-rich red-carbon quantum dots (RCQs) to dope low-temperature solution-processed SnO2 , which dramatically increases its electron mobility by ≈20 times from 9.32 × 10-4 to 1.73 × 10-2 cm2 V-1 s-1 . The mobility achieved is one of the highest reported electron mobilities for modified SnO2 . Fabricated planar PSCs based on this novel SnO2 ETL demonstrate an outstanding improvement in efficiency from 19.15% for PSCs without RCQs up to 22.77% and have enhanced long-term stability against humidity, preserving over 95% of the initial efficiency after 1000 h under 40-60% humidity at 25 °C. These significant achievements are solely attributed to the excellent electron mobility of the novel ETL, which is also proven to help the passivation of traps/defects at the ETL/perovskite interface and to promote the formation of highly crystallized perovskite, with an enhanced phase purity and uniformity over a large area. These results demonstrate that inexpensive RCQs are simple but excellent additives for producing efficient ETLs in stable high-performance PSCs as well as other perovskite-based optoelectronics.

12.
PLoS One ; 14(12): e0226726, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31856205

RESUMO

BACKGROUND: The survival of pancreatic cancer patients with lesions in different locations is unclear. In addition, the different surgery types for nonmetastatic pancreatic head cancer (PHC) or body/tail cancer (PBTC) have different prognostic influences. We analyzed the association by stage between tumor location (head vs. body/tail) and survival of nonmetastatic pancreatic cancer patients who underwent surgery. METHODS: We identified stages I to III pancreatic cancer patients who underwent surgery from 2004 through 2015 by using the Surveillance, Epidemiology, and End Results (SEER) database. The adjusted hazard ratio (HR) and 95% confidence interval (CI) for cancer-specific survival (CSS) were obtained using Cox regression. RESULTS: A total of 13517 patients or 86.6% had PHC. PHC patients were more likely to have an advanced tumor stage, higher tumor grade, and more frequent and a higher number of positive lymph nodes compared with PBTC patients. The PHC patients had a worse CSS than PBTC patients (P<0.001) and were predominantly at stage I (P = 0.008) and II (P = 0.004). Multivariate Cox regression analysis showed that PHC was an independent prognostic factor associated with a worse CSS in pancreatic cancer patients (HR 1.132, 95% CI 1.042-1.228, P = 0.003), predominantly at stage II (HR 1.128, 95% CI 1.030-1.235, P = 0.009). CONCLUSION: At a resectable early stage, the PHC patients had a worse CSS than PBTC patients after surgery. PHC was an independent prognostic factor associated with worse survival in pancreatic cancer patients, predominantly at stage II.


Assuntos
Pâncreas/patologia , Neoplasias Pancreáticas/epidemiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Análise de Sobrevida
13.
Front Cell Neurosci ; 13: 478, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31708749

RESUMO

Airway vagal nerves play a predominant role in the neural control of the airway, and augmented airway vagal activity is known to play important roles in the pathogenesis of some chronic inflammatory airway diseases. Several lines of evidence indicate that dysfunctional central orexinergic system is closely related to the severity of airway diseases, however, whether orexins affect airway vagal activity is unknown. This study investigates whether and how orexin-A regulates the activity of medullary airway vagal preganglionic neurons (AVPNs). The expression of orexin receptor type 1 (OX1R) and type 2 (OX2R) was examined using immunofluorescent staining. The effects of orexin-A on functionally identified inspiratory-activated AVPNs (IA-AVPNs), which are critical in the control of airway smooth muscle, were examined using patch-clamp in medullary slices of neonatal rats. Airway vagal response to injection of orexin-A into the magna cisterna was examined using plethysmography in juvenile rats. The results show that retrogradely labeled AVPNs were immunoreactive to anti-OX1R antibody and anti-OX2R antibody. Orexin-A dose-dependently depolarized IA-AVPNs and increased their firing rate. In synaptically isolated IA-AVPNs, the depolarization induced by orexin-A was blocked partially by OX1R antagonist SB-334867 or OX2R antagonist TCS OX2 29 alone, and completely by co-application of both antagonists. The orexin-A-induced depolarization was also mostly blocked by Na+/Ca2+ exchanger inhibitor KB-R7943. Orexin-A facilitated the glutamatergic, glycinergic and GABAergic inputs to IA-AVPNs, and the facilitation of each type of input was blocked partially by SB-334867 or TCS OX2 29 alone, and completely by co-application of both antagonists. Injection of orexin-A into the magna cisterna of juvenile rats significantly increased the inspiratory and expiratory resistance of the airway and consequently decreased the dynamic compliance of the lungs, all of which were prevented by atropine sulfate or bilateral vagotomy. These results demonstrate that orexin-A excites IA-AVPNs via activation of both OX1R and OX2R, and suggest that increased central synthesis/release of orexins might participate in the pathogenesis of airway diseases via over-activation of AVPNs.

14.
Front Microbiol ; 10: 2126, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31572332

RESUMO

Despite the convenience and non-invasiveness of fecal sampling, the fecal microbiota does not fully represent that of the gastrointestinal (GI) tract, and the efficacy of fecal sampling to accurately represent the gut microbiota in birds is poorly understood. In this study, we aim to identify the efficacy of feces as a gut proxy in birds using chickens as a model. We collected 1,026 samples from 206 chickens, including duodenum, jejunum, ileum, cecum, and feces samples, for 16S rRNA amplicon sequencing analyses. In this study, the efficacy of feces as a gut proxy was partitioned to microbial community membership and community structure. Most taxa in the small intestine (84.11-87.28%) and ceca (99.39%) could be identified in feces. Microbial community membership was reflected with a gut anatomic feature, but community structure was not. Excluding shared microbes, the small intestine and ceca contributed 34.12 and 5.83% of the total fecal members, respectively. The composition of Firmicutes members in the small intestine and that of Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria members in the ceca could be well mirrored by the observations in fecal samples (ρ = 0.54-0.71 and 0.71-0.78, respectively, P < 0.001). However, there were few significant correlations for each genus between feces and each of the four gut segments, and these correlations were not high (ρ = -0.2-0.4, P < 0.05) for most genera. Our results suggest that fecal microbial community has a good potential to identify most taxa in the chicken gut and could moderately mirror the microbial structure in the intestine at the microbial population level with phylum specificity. However, it should be interpreted with caution by using feces as a proxy to study associations for microbial structure at individual microorganism level.

15.
Soft Robot ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31584322

RESUMO

Soft actuators and robotics have been widely researched in recent years mainly due to their compliance to environments and safe interaction with humans. However, the need of tether and low energy efficiency of such actuators/robots has limited their practical applications. This article presents a novel tendon-driven soft actuator concept that has the property of self-pumping, called soft self-pumping actuator (SSPA) in this research. A SSPA is designed by assembling two soft pneumatic actuators (SPAs) face-to-face, whose air chambers are connected by two check valves. Actuation of the SSPA is achieved by tendons that allows precise and untethered control compared with traditional SPAs. The two chambers in the proposed actuators are precharged with air to a desired pressure to enlarge self-stiffness and to facilitate bending. When actuated, one chamber will be compressed and serve as a pump to inject its air into the other chamber, resulting in further bending of the actuator. The airflow involves energy transmission to help the intended actuation, thus improving energy efficiency. In experimental studies, differential chamber air pressure is found to reduce the force in initiating actuator bending. Experimental results have also shown that energy efficiency increase of up to 45% has been achieved compared with the same design but without air transmission. We believe that the proposed concept could lead to more novel designs of controllable and energy saving soft robots.

16.
World J Gastroenterol ; 25(39): 6006-6015, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31660036

RESUMO

BACKGROUND: In pancreatic cancer, acute pancreatitis (AP) is a serious morbidity, but its negative effect on long-term outcomes remains to be elucidated. AIM: To investigate the effects of AP on the tumor recurrence pattern of pancreatic ductal adenocarcinoma (PDAC) and tumor-specific survival. METHODS: The medical records of 219 patients with curative pancreatectomy for pancreatic cancer at the Pancreatic Surgery Center of West China Hospital from July 2012 to December 2016 were analyzed retrospectively. The severity of acute pancreatitis was classified according to the Atlanta classification of AP. The patient demographics and tumor characteristics were assessed. Early recurrence was defined as a relapse within 12 mo after surgery. Overall and disease-free survival and recurrence patterns were analyzed. Mild acute pancreatitis was excluded because its negative effects can be negligible. RESULTS: Early recurrence in AP group was significantly higher than in non-AP group (71.4% vs 41.2%; P = 0.009). Multivariate analysis of postoperative early recurrence showed that moderate or severe AP was an independent risk factor for an early recurrence [odds ratio (OR): 4.13; 95% confidence interval (CI): 1.41-12.10; P = 0.01]. The median time to recurrence was shorter in patients with AP than in those without (8.4 vs 12.8 mo; P = 0.003). Multivariate analysis identified AP as an independent prognostic factor for overall survival [relative risk (RR): 2.35; 95%CI: 1.45-3.83] and disease-free survival (RR: 2.24; 95%CI: 1.31-3.85) in patients with PDAC. CONCLUSION: Patients with moderate or severe acute pancreatitis developed recurrences earlier than those without. Moderate or severe AP is associated with shorter overall and disease-free survival of patients with PDAC.


Assuntos
Carcinoma Ductal Pancreático/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Pancreatite/epidemiologia , Adulto , Idoso , Carcinoma Ductal Pancreático/complicações , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/mortalidade , China , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Pâncreas/cirurgia , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/mortalidade , Pancreatite/diagnóstico , Pancreatite/etiologia , Pancreatite/cirurgia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Análise de Sobrevida , Fatores de Tempo
17.
Bioinspir Biomim ; 14(6): 066008, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31430730

RESUMO

Research on quadrupedal robots inspired by canids or felids have been widely reported and demonstrated. However, none of these legged robots can deal with difficult environments that include water, such as small lakes, streams, rain, mud, flooded terrain, etc. In this paper, we present for the first time a kinematic analysis and a hydrodynamic model of dog paddling motion in a robotic system. The quadrupedal paddling gait of dogs was first analyzed based on underwater video recording. Hydrodynamic drag force analysis in a paddling gait cycle was conducted for a prototype robotic dog. The prototype robotic dog was developed using four pre-charged pneumatics soft actuators with consideration of relative positions of CG (center of gravity) and CB (center of buoyancy) and their dynamic variation in paddling. It was found that such soft actuators have great potential in developing amphibious legged robots, because they are inherently water-tight, anti-rusty, simple in structural design, and have large hydrodynamic advantage due to their mostly hemi-cylindrical shape design. Trotting and paddling of the prototype robotic dog was also demonstrated. It is believed that our findings reported in this research will provide useful guidance in future development of amphibious robotic dogs.

18.
BMC Surg ; 19(1): 83, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286902

RESUMO

BACKGROUND: Chronic pancreatitis (CP) is considered to be a risk factor for pancreatic cancer. A retrospective study was conducted to evaluate the incidence of pancreatic cancer after surgery for CP and to determine the risk factors. METHODS: The patients who underwent surgery for histologically documented CP between January 2009 and December 2017 were reviewed. The baseline characteristics, operative data, postoperative complications, and follow-up information were analysed. We calculated standardized incidence ratio on the base of the incidence of pancreatic cancer in the standard population in China. The risk factor for pancreatic cancer was assessed using Cox regression. RESULTS: Among 650 patients, pancreatic cancer was detected in 12 patients (1.8%) after a median follow-up of 4.4 years. The standardized incidence ratio of pancreatic cancer was 68.12 (95% CI, 35.20-118.99). Two independent risk factors for the development of pancreatic cancer in patients with chronic pancreatitis after surgery were identified: time interval to surgery [HR 1.005, 95% CI (1.002-1.008), P = 0.002] and de novo endocrine insufficiency [HR 10.672, 95% CI (2.567-44.372), P = 0.001]. CONCLUSIONS: Patients who require surgery for CP are at a very high risk of developing pancreatic cancer. Early surgical intervention plays a protective role in the development of pancreatic cancer from CP. A high index of suspicion for pancreatic cancer should be maintained in CP patients with de novo postoperative diabetes after surgery.


Assuntos
Neoplasias Pancreáticas/epidemiologia , Pancreatite Crônica/complicações , Pancreatite Crônica/cirurgia , Adulto , China/epidemiologia , Insuficiência Pancreática Exócrina/etiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Pancreatectomia , Neoplasias Pancreáticas/etiologia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/prevenção & controle , Pancreaticojejunostomia , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Tempo para o Tratamento
19.
ACS Appl Mater Interfaces ; 11(32): 29132-29138, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31333010

RESUMO

Interfacial engineering between charge transport layers and perovskite light-emitting layers has been applied as an effective strategy to enhance performance of perovskite light-emitting diodes (PeLEDs). Herein, we introduce a Lewis base diamine molecule [2,2-(ethylenedioxy)bis(ethylammonium), EDBE] to modify the interface between the ZnMgO electron transport layer (ETL) and perovskite light-emitting layer in PeLEDs. With two amino groups in EDBE, one amine can interact with ZnMgO beneath to tune the growth of perovskite films, resulting in improved electron injection and suppressed current leakage. Meanwhile, the other amine can passivate the surface trap states of the polycrystalline perovskite films, which would eliminate trap-mediated nonradiative recombination. An enhanced performance for near-infrared PeLEDs is achieved with external quantum efficiency from 9.15 to 12.35% after incorporating the EDBE interfacial layer. This work demonstrated that the introduction of Lewis base diamine molecules as the ETL/perovskite interfacial agent is a promising way for developing high-performance PeLEDs.

20.
Int J Phytoremediation ; 21(11): 1153-1160, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31084357

RESUMO

The contamination of toxic heavy metals was a major issue of concern in the last century. A fast-growing metal-accumulating woody plant is a promising approach for the remediation of toxic heavy metal. In this study, the transportation of heavy metals (Pb, Zn, Cu, and Cd) in Paulownia fortunei cultivated in lead-zinc slag amended with different mass ratios of peat (CK: 0; T1: 10%; T2: 20%; T3: 30%) was investigated, as well as the subcellular distribution of Pb, Zn, Cu, and Cd in Paulownia fortunei. The results showed that the accumulation content of Pb, Zn, Cu, and Cd in Paulownia fortunei were increased with peat amendment, which was in the range of 4.216 ∼ 6.853, 20.905 ∼ 23.017, 1.898 ∼ 2.572, and 0.530 ∼ 0.616 mg/pot, respectivly. The experimental group with 30% dose of peat showed the best performance on the accumulation content of Pb, Zn, Cu, and Cd, with increase rates (compared to control) of 4.088, 10.573, 1.360, and 0.294 mg/pot, respectively. The bioconcentration, translocation and transfer quantity factor of Pb, Zn, Cu, and Cd were less than 1. Fixation of cell wall and compartmentalization of vacuolar appeared to play an important role in reducing the toxicity of Pb, Zn, Cu, and Cd.


Assuntos
Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Chumbo , Solo , Zinco
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