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1.
ACS Nano ; 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32271535

RESUMO

Performance of 2D photodetectors is often predominated by charge traps that offer an effective photogating effect. The device features an ultrahigh gain and responsivity, but at the cost of a retarded temporal response due to the nature of long-lived trap states. In this work, we devise a gain mechanism that originates from massive charge puddles formed in the type-II 2D lateral heterostructures. This concept is demonstrated using graphene-contacted WS2 photodetectors embedded with WSe2 nanodots. Upon light illumination, photoexcited carriers are separated by the built-in field at the WSe2/WS2 heterojunctions (HJs), with holes trapped in the WSe2 nanodots. The resulting WSe2 hole puddles provide a photoconductive gain, as electrons are recirculating during the lifetime of holes that remain trapped in the puddles. The WSe2/WS2 HJ photodetectors exhibit a responsivity of 3 × 102 A/W with a gain of 7 × 102 electrons per photon. Meanwhile, the zero-gate response time is reduced by 5 orders of magnitude as compared to the prior reports for the graphene-contacted pristine WS2 monolayer and WS2/MoS2 heterobilayer photodetectors due to the ultrafast intralayer excitonic dynamics in the WSe2/WS2 HJs.

2.
Anal Bioanal Chem ; 412(8): 1785-1794, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32052065

RESUMO

The prevalence of allergic rhinitis (AR) is increasing worldwide. However, the current systems used to measure levels of immunoglobulin E (IgE) in sera are associated with several disadvantages that limit their further application. Consequently, there is a need to develop novel highly sensitive strategies that can rapidly detect IgE in a quantitative manner. The development of such systems will significantly enhance our ability to diagnose, treat, and even prevent AR. Herein, we describe our experience of using quantum dot-based lateral flow immunoassay (QD-LFIA), combined with a portable fluorescence immunoassay chip detector (PFICD), to detect serum-specific IgE against Dermatophagoides pteronyssinus (Der-p) and Dermatophagoides farinae (Der-f), two common mite allergens in China. Our data showed that our system could detect serum-specific levels of IgE against Der-p and Der-f as low as 0.093 IU/mL and 0.087 IU/mL, respectively. We also established a standard curve to determine serum-specific IgE concentrations that correlated well with the clinical BioIC microfluidics system. The sensitivity of our assay was 96.7% for Der-p and 95.5% for Der-f, while the specificity was 87.2% for Der-p and 85.3% for Der-f. Collectively, our results demonstrate that QD-LFIA is a reliable system that could be applied to detect serum-specific IgE in accordance with clinical demands. This QD-LFIA strategy can be applied at home, in hospitals, and in pharmacies, with reduced costs and time requirements when compared with existing techniques. In the future, this system could be developed to detect other types of allergens and in different types of samples (for example, whole blood). Graphical abstract We describe our experiment using a quantum dot-based lateral flow immunoassay combined with a portable fluorescence immunoassay chip detector for both qualitative and quantitative detection of serum-specific IgE against two common mite allergens. This strategy can be applied at home, in hospitals, and in pharmacies, with reduced costs and time requirements. In the future, this system could be developed to detect other types of allergens and in different types of samples.


Assuntos
Alérgenos/sangue , Imunoensaio/métodos , Imunoglobulina E/sangue , Pontos Quânticos , Rinite Alérgica/sangue , Humanos , Limite de Detecção , Sistemas Automatizados de Assistência Junto ao Leito , Rinite Alérgica/imunologia
3.
ACS Nano ; 14(1): 985-992, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31904930

RESUMO

The most pressing barrier for the development of advanced electronics based on two-dimensional (2D) layered semiconductors stems from the lack of site-selective synthesis of complementary n- and p-channels with low contact resistance. Here, we report an in-plane epitaxial route for the growth of interlaced 2D semiconductor monolayers using chemical vapor deposition with a gas-confined scheme, in which patterned graphene (Gr) serves as a guiding template for site-selective growth of Gr-WS2-Gr and Gr-WSe2-Gr heterostructures. The Gr/2D semiconductor interface exhibits a transparent contact with a nearly ideal pinning factor of 0.95 for the n-channel WS2 and 0.92 for the p-channel WSe2. The effective depinning of the Fermi level gives an ultralow contact resistance of 0.75 and 1.20 kΩ·µm for WS2 and WSe2, respectively. Integrated logic circuits including inverter, NAND gate, static random access memory, and five-stage ring oscillator are constructed using the complementary Gr-WS2-Gr-WSe2-Gr heterojunctions as a fundamental building block, featuring the prominent performance metrics of high operation frequency (>0.2 GHz), low-power consumption, large noise margins, and high operational stability. The technology presented here provides a speculative look at the electronic circuitry built on atomic-scale semiconductors in the near future.

4.
Biomolecules ; 10(1)2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31963204

RESUMO

Since the first discovery in 1961, more than 1300 ent-kaurane diterpenoids have been isolated and identified from different plant sources, mainly the genus Isodon. Chemically, they consist of a perhydrophenanthrene subunit and a cyclopentane ring. A large number of reports describe the anticancer potential and mechanism of action of ent-kaurane compounds in a series of cancer cell lines. Oridonin is one of the prime anticancer ent-kaurane diterpenoids that is currently in a phase-I clinical trial in China. In this review, we have extensively summarized the anticancer activities of ent-kaurane diterpenoids according to their plant sources, mechanistic pathways, and biological targets. Literature analysis found that anticancer effect of ent-kauranes are mainly mediated through regulation of apoptosis, cell cycle arrest, autophagy, and metastasis. Induction of apoptosis is associated with modulation of BCL-2, BAX, PARP, cytochrome c, and cleaved caspase-3, -8, and -9, while cell cycle arrest is controlled by cyclin D1, c-Myc, p21, p53, and CDK-2 and -4. The most common metastatic target proteins of ent-kauranes are MMP-2, MMP-9, VEGF, and VEGFR whereas LC-II and mTOR are key regulators to induce autophagy.

5.
Clin Otolaryngol ; 45(2): 167-176, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31573757

RESUMO

BACKGROUND: Pre-treatment serum albumin (ALB) is a novel index that was identified in recent years and is considered to be closely related to the prognosis of nasopharyngeal carcinoma (NPC). However, the association between ALB and NPC remains controversial. OBJECTIVE OF REVIEW: To assess the prognostic significance of pre-treatment serum ALB in patients with NPC. TYPE OF REVIEW: A systematic review and meta-analysis. SEARCH STRATEGY: We searched PubMed, the Cochrane Library and the Web of Science for studies published up to August 2018. The keywords used were related to albumin, nasopharyngeal carcinoma and prognosis. EVALUATION METHOD: We extracted the following data from all included studies: author, publication year, country, cancer centre, time points of randomisation, sample size, mean or median age, gender, TNM stage of NPC, cut-off value of pre-treatment serum albumin, number of high-grade cases and duration of follow-up. Then, we generated the pooled hazard ratios (HR) for overall survival (OS) and distant metastasis-free survival (DMFS) to perform this meta-analysis. RESULTS: Ten studies comprising 7339 cases were included. Lower pre-treatment serum ALB levels were significantly associated with worse OS (HR = 1.32, 95% CI 1.17-1.48) and DMFS (HR = 1.40, 95% CI 1.08-1.80). In general, our findings were further verified in the subgroup analyses based on three features, including cancer stage, cut-off value and analysis type. CONCLUSION: A decreased level of pre-treatment serum albumin implies a poor prognosis and can be detected to define the risk stratification of NPC patients.

6.
BMC Musculoskelet Disord ; 20(1): 632, 2019 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-31884960

RESUMO

BACKGROUND: Although the risk factors associated with osteonecrosis of femoral head (ONFH) after internal fixation of femoral neck fracture (IFFNF) have been frequently reported, the results remain controversial. Therefore, its related risk factors were systematically evaluated and meta-classified in this study. METHODS: Literature on risk factors of ONFH caused by IFFNF was retrieved in PubMed, Embase and Cochrane Library due June 2019. Review Manager 5.3 software was applied to data synthesis, and Stata 13.0 software was adopted for analyses of publication bias and sensitivity. RESULTS: A total of 17 case-control studies with 2065 patients were included. The risk of ONFH after IF was 0.40-fold higher in patients with Garden III-IV FNF than that in patients with Garden I-II (OR: 0.40, 95%CI: 0.29-0.55). The risk of OFNH with retained IF was uplifted by 0.04 times (OR: 0.04, 95%CI: 0.02-0.07). There was nonsignificant relationship between gender and ONFH after IFFNF (OR: 1.27, 95%CI: 0.84-1.94). Moreover, ONFH after IFFNF presented no association with age (OR:1.66, 95%CI: 0.89-3.11), injury-operation interval (OR:1.29, 95%CI: 0.82-2.04), fracture reduction mode (OR:1.98, 95%CI: 0.92-4.26), preoperative traction (OR:1.69, 95%CI: 0.29-9.98) and mechanism of injury (OR:0.53, 95%CI: 0.06-4.83). Egger's and Begg's tests indicated a publication bias (P = 0.001). CONCLUSION: It was demonstrated that Garden classification and retained IF were important influencing factors of ONFH after IFFNF. Gender, age, injury-operation interval, fracture reduction mode, preoperative traction and the mechanism of ONFH were irrelevant to the complication.


Assuntos
Fraturas do Colo Femoral/cirurgia , Necrose da Cabeça do Fêmur/epidemiologia , Fixação Interna de Fraturas/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Fatores Etários , Feminino , Fraturas do Colo Femoral/complicações , Necrose da Cabeça do Fêmur/etiologia , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Complicações Pós-Operatórias/etiologia , Fatores de Risco , Fatores Sexuais , Fatores de Tempo
7.
Zhongguo Zhong Yao Za Zhi ; 44(20): 4448-4453, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31872631

RESUMO

Musk,with unique and intense perfume,was a kind of deep brown precious medicinal material in traditional Chinese medicine. However,the immature musk in musk pot was white and stench. Given the fact that bacterial diversity generated odorous metabolites in animal hosts,in this study,musk samples at three different mature stages,including MJ( the end of June),MA( the end of August) and MO( the end of October) were harvested from three male forest musk deer,and then next-generation sequencing was used to intensively survey the bacterial communities in musk harvested at different mature stages. RESULTS: indicated that the average OTUs per sample at the end of June,August and October were 47 116. 00 ± 1 567. 24( SE),52 009. 00 ± 8 958. 75( SE) and50 004. 67±4 135. 57( SE),respectively. Feature of the musk 16 S rRNA gene showed a total of 418 genera belonging to 52 phyla were observed in all samples. The main microbiota was bacteria,which accounted for 98. 82%,99. 95% and 99. 58% in MJ,MA and MO,respectively. At phylum level,Firmicutes was the most abundant bacterial of MA( 32. 75%) and MO( 39. 19%). While,the major bacterial in MJ was Proteobacteria( 49. 14%). PICRUSt analysis revealed the functions of bacterial in MJ were mainly involved in secretion,while bacterial functions of MA and MO were mainly involved in amino acid or other substance metabolism,which was in accord with the musk secretion physiological process of forest musk deer. This is the first study involved in the bacterial diversity in musk of forest musk deer across the maturation process,while may provide a new insight into the musk generation mechanism.


Assuntos
Cervos/microbiologia , Ácidos Graxos Monoinsaturados , Animais , Florestas , Sequenciamento de Nucleotídeos em Larga Escala , Masculino
8.
ACS Appl Mater Interfaces ; 11(39): 35969-35976, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31532619

RESUMO

InSe is a high-mobility layered semiconductor with mobility being highly sensitive to any surrounding media that could act as a source of extrinsic scattering. However, little effort has been made to understand electronic transport in thin InSe layers with native surface oxide formed spontaneously upon exposure to an ambient environment. Here, we explore the influence of InOx/InSe interfacial trap states on electronic transport in thin InSe layers. We show that wet oxidation (processed in an ambient environment) causes massive deep-lying band-tail states, through which electrons conduct via 2D variable-range hopping with a short localization length of 1-3 nm. In contrast, a high-quality InOx/InSe interface can be formed in dry oxidation (processed in pure oxygen), with a low trap density of 1012 eV-1 cm-2. Metal-insulator transition can be thus observed in the gate sweep of the field-effect transistors (FETs), indicative of band transport predominated by extended states above the mobility edge. A room-temperature band mobility of 103 cm2/V s is obtained. The profound difference in the transport behavior between the wet and dry InSe FETs suggests that fluctuating Coulomb potential arising from trapped charges at the InOx/InSe interface is the dominant source of disorders in thin InSe channels.

9.
Ann Transl Med ; 7(14): 341, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31475211

RESUMO

Background: To compare surgical outcomes after mitral valve replacement via either minimally invasive thoracoscopic (MIs) or traditional median sternotomy (MS) surgery and determine the short- and mid-term clinical outcomes of the MI approach. Methods: All patients who received either MIs (n=405) or MS (n=691) mitral valve replacement surgery at the Guangdong Cardiovascular Institute between January 2012 and July 2015 were analyzed for outcome differences due to surgical approach using propensity score matching. The best 202 matches from the MI group and the MS group were analyzed. The clinical data of the two groups were collected, including preoperative cardiac function, operative data, postoperative complications, and follow-up. Results: A final total of 404 patients were included in this study after propensity score matching; the MIs group and the MS group each contained 202 patients. The two groups were similar in age, weight, pathological changes, and surgical approach. Compared with the MS group, the MIs group had a longer cardiopulmonary bypass time (P<0.001), aortic cross-clamping time (P<0.001), and total procedure time (P<0.001). There were no significant differences between the groups regarding in-hospital mortality, stroke, pneumonia, acute renal failure, arrhythmia, and chylothorax. The MS group had significantly more patients with poor wound healing than the MIs group (P=0.004). The MI group had a lower rate of transfusion (P=0.037), shorter ventilation time (P=0.041), shorter ICU stay (P=0.033), reduced chest tube drainage and length of chest tube stay (P<0.001), and shorter hospital stay (P<0.001). There was no significant difference between the groups in hospital re-admission for bleeding, but the total hospitalization cost was higher in the MIs group (P=0.002). The mean follow-up was 26.59±12.33 months, the 1-year postoperative survival rate was 98.86%, and the overall survival rate was 97.44%. Compared with the MS group, the MIs group recovered earlier (P<0.05), and returned to work or study earlier (P<0.05). More patients in the MIs group were satisfied with the wound (P<0.001). The MS group had a higher incidence of postoperative osteomyelitis than the MIs group (P=0.028). There were no significant differences between groups in rates of mortality, stroke, pacemaker, reoperation, or 36-item Short Form Health Survey score. Conclusions: Compared with the MS approach, the MIs method of mitral valve replacement has longer cardiopulmonary bypass time and aortic cross-clamp time; however, it does not increase the risk of mortality and complications. Furthermore, MIs causes less trauma, fewer transfusions, less wound infection, faster recovery, faster return to work or study, and greater satisfaction with the incision in the mid-term. MI cardiac surgery is safe, effective, and feasible.

11.
J Cardiothorac Surg ; 14(1): 105, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31186011

RESUMO

BACKGROUND: Rib fractures account for a fairly high proportion of chest injuries, ranging from 55 to 80%. The most common mechanisms of injury include: traffic accident, extrusion and falls from significant heights. Besides, the surgical treatment of multiple rib fractures has been accepted by more and more medical professionals. We reported 5 clinical cases of patients with multiple rib fractures undergoing open reduction and internal fixation using 3D printing technology. CASE PRESENTATION: Retrospective analysis of 5 clinical cases of multiple rib fractures from January 2017 to August 2018 in our hospital. A preoperative CT thin slice scan was used to reconstruct the 3D model according to the scanning results, and 3D printing technology was adopted to prepare the rib model. Preoperative reconstruction of the rib's normal shape and lock plate for the shaped ribs was created according to reconstructed model. For multiple fractures especially patients with severely deformed rib shape, it is suggested to intraoperative shape directly to the metal bone plate fixed on the ribs on both ends of the fracture line, in order to establish a basic support frame. The other various fracture section can be fixed on the lock plate respectively. Postoperative chest radiographs of the 5 patients showed that the internal fixations were in good and natural shape. The thoracic contour was well formed and symmetrically with the contralateral side. CONCLUSION: Making the rib model and the pre-shaped titanium alloy rib locking plate using 3D printing technology, provided a more minimally invasive and precisely individualized treatment for some rib fracture operations.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/métodos , Fraturas Múltiplas/cirurgia , Redução Aberta/métodos , Impressão Tridimensional , Fraturas das Costelas/cirurgia , Acidentes por Quedas , Acidentes de Trânsito , Feminino , Fixação Interna de Fraturas/instrumentação , Fraturas Múltiplas/diagnóstico por imagem , Fraturas Múltiplas/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Redução Aberta/instrumentação , Período Pós-Operatório , Radiografia , Estudos Retrospectivos , Fraturas das Costelas/diagnóstico por imagem , Fraturas das Costelas/etiologia , Tomografia Computadorizada por Raios X
12.
ACS Nano ; 13(7): 8146-8154, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31244047

RESUMO

Contact engineering has been the central issue in the context of high-performance field-effect transistors (FETs) made of atomic thin transition metal dichalcogenides (TMDs). Conventional metal contacts on TMDs have been made on top via a lithography process, forming a top-bonded contact scheme with an appreciable contact barrier. To provide a more efficient pathway for charge injection, an end-bonded contact scheme has been proposed, in which covalent bonds are formed between the contact metal and channel edges. Yet, little efforts have been made to realize this contact configuration. Here, we bridge this gap and demonstrate seeded growth of end-bonded contact with different TMDs by means of chemical vapor deposition (CVD). Monolayer WSe2 FETs with a CVD-grown channel and end contacts exhibit improved performance metrics, including an on-current density of 30 µA/µm, a hole mobility of 90 cm2/V·s, and a subthreshold swing of 94 mV/dec, an order of magnitude superior than those of top-contact FET counterparts that share the same channel material. A fundamental NOT logic gate constructed using top-gated and end-bonded WSe2 and MoS2 FETs is also demonstrated. Calculations using density functional theory indicate that the superior device performance stems mainly from the stronger metal-TMD hybridization and substantial gap states in the end-contact configuration.

13.
J Cell Physiol ; 234(12): 22082-22092, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31066044

RESUMO

Endothelial progenitor cells (EPCs) belong to bone marrow-derived myeloid progenitor cells that have strong proliferative ability. Dysregulation of miRNAs after acute myocardial infarction (AMI) can result in EPCs injury, thus we hypothesize that correction of miRNA expression may contribute to the tolerance of EPCs against oxidative stress. The peripheral blood of healthy volunteers and patients with ST-segment elevation myocardial infarction (STEMI) was clinically collected. EPCs derived from peripheral blood were transfected by miR-324-5p mimic and simultaneously handled with hydrogen peroxide (H2 O2 ) to inducing EPCs injury. At 24 hrs after the H2 O2 treatment, cell viability, the uptake capacity on DiI-Ac-LDL, and carrying ability on FITC-UEA-l and multiplication capacity were analyzed. The mechanism process was carefully researched by valued the characteristics of the mitochondrion morphology, membrane potential, ATP levels, and the expressing of apoptosis pathways. Small RNA sequencing indicated that the expression level of miR-324-5p in peripheral blood EPCs of patients with STEMI was significantly lower compared with the healthy volunteers. The Mtfr1 has been confirmed as a targeted gene of miR-324-5p through miRTarBase software and western blot. The miR-324-5p mimic units could be contributed for the improvement of viability, the uptake capacity on DiI-Ac-LDL and carrying ability on FITC-UEA-l and multiplication capacity on oxidative stress-injured EPCs. miR-324-5p could suppress mitochondrial fragmentation, promote membrane potential, and ATP levels, as well as protect against oxidative stress-induced EPCs apoptosis. Our results suggested that miR-324-5p protects against oxidative stress-induced EPCs injury by regulating Mtfr1.

14.
J Cardiothorac Surg ; 14(1): 83, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31036030

RESUMO

BACKGROUND: To investigate the application of 3D printing technology combined with percutaneous Minimally Invasive Plate Oseoynthesis (MIPO) and thoracoscopic techniques in the treatment of long comminuted rib fractures. CASE PRESENTATION: One case of multiple rib fractures with abnormal respiratory disease (including rib 3 and 4 of long comminuted fractures) due to a fall injury was selected. The 3D model of comminuted rib fracture was reconstructed and printed according to the thin-layer CT scan results. After the fracture model was restored to the normal rib anatomy, the metal plate was accurately shaped according to the 3D rib shape. CONCLUSIONS: 3D printing technology combined with MIPO technology under thoracoscopy in the minimally invasive treatment of long-range comminuted rib fractures, greatly reduced the time and improved the accuracy of intraoperative fixation, reduced the difficulty of surgery, patient injury, and perfectly reconstructed the chest wall. Application of the 3D printing technique to make the rib model and pre-mold the metal plate combined the thoracoscopic MIPO technology provides less invasive and accurate individualized treatment for complex rib fractures.


Assuntos
Fixação Interna de Fraturas/métodos , Fraturas Cominutivas/cirurgia , Impressão Tridimensional , Fraturas das Costelas/cirurgia , Toracoscopia , Acidentes por Quedas , Placas Ósseas , Fraturas Cominutivas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Procedimentos Cirúrgicos Reconstrutivos , Fraturas das Costelas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento
15.
Reprod Domest Anim ; 54(8): 1069-1077, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31099063

RESUMO

Spermatozoa are highly specialized cells, and energy metabolism plays an important role in modulating sperm viability and function. Rosiglitazone is an antidiabetic drug in the thiazolidinedione class that regulates metabolic flexibility and glucose uptake in various cell types, but its effects on boar sperm metabolism are unknown. In this study, we investigated the potential effect of rosiglitazone against time-dependent deterioration of boar spermatozoa during liquid preservation at 17°C. Freshly ejaculated semen was diluted with Beltsville Thawing Solution (BTS) containing different concentrations of rosiglitazone, and the motility, membrane and acrosome integrity of sperm were detected. Besides, we measured glucose uptake capacity, l-lactate production level, mitochondrial membrane potential, adenosine triphosphate (ATP) content and mitochondrial reactive oxygen species (mROS) production of sperm after boar semen had been incubated with or without rosiglitazone, iodoacetate (glycolysis inhibitor) and rotenone (electron transport chain inhibitor) for 5 days. The addition of rosiglitazone significantly enhanced sperm quality and had a strong protective effect on the sperm membrane and acrosome integrity during storage. BTS containing 50 µM rosiglitazone maintained the total motility of liquid-preserved sperm above 60% for 7 days. Rosiglitazone improved sperm quality by regulating energy metabolism manner of preserved sperm, protected the sperm mitochondrial membrane potential, enhanced sperm ATP production and in the meanwhile reduced mROS through enhancing glycolysis but not oxidative phosphorylation. The data suggested the practical feasibility of using rosiglitazone for improving boar spermatozoa quality during semen preservation.


Assuntos
Hipoglicemiantes/farmacologia , Rosiglitazona/farmacologia , Preservação do Sêmen/veterinária , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Suínos , Animais , Crioprotetores/farmacologia , Metabolismo Energético , Masculino , Motilidade Espermática
16.
Artigo em Inglês | MEDLINE | ID: mdl-30993665

RESUMO

BACKGROUND: To investigate the regulatory mechanism of local lymphatic reconstruction after cupping therapy in a mouse model. MATERIALS AND METHODS: The lymphatic reconstruction process in the mouse tail after cupping therapy as well as the expression levels of the vascular endothelial identification molecule CD34, prospero homeobox protein 1 (PROX1), and lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) were investigated for a duration of 4 days through immunohistochemistry experiments. RESULTS: On day 1 after cupping therapy, the CD34+ and LYVE-1+ cell densities were significantly increased, and the formed CD34+LYVE-1+ tubular structure started to express PROX1. This was followed by a decrease in both the CD34+ and LYVE-1+ stem cell densities to basal levels on the second day after cupping therapy. Both the CD34+ and LYVE-1+ cell densities subsequently increased again on the third day after cupping therapy. The increase in the LYVE-1+ density was accompanied by tubular structure formation, which is characteristic of lymphangiogenesis. In addition, the colocalization of CD34+ and LYVE-1+ cells by immunohistochemistry suggests that the CD34+ stem cells differentiated into new lymphatic endothelial cells. CONCLUSIONS: Our findings indicate that the mechanism underlying the therapeutic effect of cupping therapy involves upregulation of vascular and lymphatic endothelial markers (CD34+, LYVE-1+, and CD34+LYVE-1+) in local tissues, which in turn promotes local new lymphatic vessel formation through the expression of PROX1.

17.
Sci Adv ; 5(3): eaau5655, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30899782

RESUMO

Lithium metal-based batteries are attractive energy storage devices because of high energy density. However, uncontrolled dendrite growth and virtually infinite volume change, which cause performance fading and safety concerns, have limited their applications. Here, we demonstrate that a composite lithium metal electrode with an ion-conducting mesoscale skeleton can improve electrochemical performance by locally reducing the current density. In addition, the potential for short-circuiting is largely alleviated due to side deposition of mossy lithium on the three-dimensional electroactive surface of the composite electrode. Moreover, the electrode volume only slightly changes with the support of a rigid and stable scaffold. Therefore, this mesoscale composite electrode can cycle stably for 200 cycles with low polarization under a high areal current density up to 5 mA/cm2. Most attractively, the proposed fabrication process, which only involves simple mechanical deformation, is scalable and cost effective, providing a new strategy for developing high performance and long lifespan lithium anodes.

18.
Sensors (Basel) ; 19(6)2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30875740

RESUMO

The driver gaze zone is an indicator of a driver's attention and plays an important role in the driver's activity monitoring. Due to the bad initialization of point-cloud transformation, gaze zone systems using RGB-D cameras and ICP (Iterative Closet Points) algorithm do not work well under long-time head motion. In this work, a solution for a continuous driver gaze zone estimation system in real-world driving situations is proposed, combining multi-zone ICP-based head pose tracking and appearance-based gaze estimation. To initiate and update the coarse transformation of ICP, a particle filter with auxiliary sampling is employed for head state tracking, which accelerates the iterative convergence of ICP. Multiple templates for different gaze zone are applied to balance the templates revision of ICP under large head movement. For the RGB information, an appearance-based gaze estimation method with two-stage neighbor selection is utilized, which treats the gaze prediction as the combination of neighbor query (in head pose and eye image feature space) and linear regression (between eye image feature space and gaze angle space). The experimental results show that the proposed method outperforms the baseline methods on gaze estimation, and can provide a stable head pose tracking for driver behavior analysis in real-world driving scenarios.


Assuntos
Movimentos da Cabeça/fisiologia , Algoritmos , Movimentos Oculares/fisiologia , Humanos , Modelos Lineares
19.
ChemSusChem ; 12(10): 2154-2160, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-30767387

RESUMO

The high-value-added chemicals hydroxyacetone (HA) and 1-hydroxy-2-butanone (HB) were produced from agricultural waste over a Ni3 Sn4 -SnOx catalyst. The Sn-Ni intermetallic compound and SnOx acted as the active sites for HA and HB production by selectively cleaving the target C-C and C-O bonds. Approximately 70 % of the total HA and HB yield was obtained by selective hydrogenolysis of cellulose. This strategy expands the application of cellulose towards renewable production of high-value C3 and C4 keto-alcohols from cellulosic biomass.

20.
ACS Nano ; 13(3): 3269-3279, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30790512

RESUMO

One of the primary limitations of previously reported two-dimensional (2D) photodetectors is a low frequency response (≪ 1 Hz) for sensitive devices with gain. Yet, little efforts have been devoted to improve the temporal response of photodetectors while maintaining high gain and responsivity. Here, we demonstrate a gain of 6.3 × 103 electrons per photon and a responsivity of 2.6 × 103 A/W while simultaneously exhibiting an ultrafast response time of 40-65 µs in a hybrid photodetector that consists of graphene-WS2-graphene junctions covered with indium (In) adatoms atop. The resultant responsivity is 6 orders of magnitude higher than that of conventional photodetectors comprising solely of a Au-WS2-Au junction. The photogain is provided mainly by the adsorbed In adatoms, from which photogenerated electrons can be transferred to the WS2 channel, while holes remain trapped in In adatoms, leading to a photogating effect as electrons are recirculating during the residence of holes in In adatoms. At a gate voltage near the Dirac point of graphene, a detectivity of D* = 2.2 × 1012 Jones and an ON/OFF ratio of 104 are achieved. The enhanced performance of the device can be attributed partly to the transparent graphene/WS2 contact and partly to the strong capacitive coupling of the In adatoms with the WS2 channel, which enables ultrafast carrier dynamics.

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