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1.
Small Methods ; : e2400779, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38940078

ABSTRACT

Bionic visual systems require multimodal integration of eye-like photodetectors and brain-like image memory. However, the integration of photodetectors (PDs) and artificial optoelectronic synapses devices (OESDs) by one device remains a giant challenge due to their photoresponse discrepancy. Herein, a dual-functional integration of PDs and OESDs based on VO2/WO3 heterojunctions is presented. The device can be able to realize a dual-mode conversion between PDs and OESDs through tuning the bias voltage. Under zero bias voltage, the device exhibiting excellent photodetecting behaviors based on the photovoltaic effect, showing a high self-powered photoresponsivity of 18.5 mA W-1 and high detectivity of 7.5 × 1010 Jones with fast photoresponse. When the external bias voltages are applied, it can be acted as an OESD and exhibit versatile electrical and photonic synaptic characteristics based on the trapping and detrapping effects, including synaptic plasticity and learning-experience behaviors. More importantly, benefiting from the excellent photosensing ability and transporting properties, the device shows ultralow-power consumption of 39.0 pJ and a 4 × 4 OESDs array is developed to realize the visual perception and memory. This work not only supplies a novel route to realize complex functional integration just in one device, but also offers effective strategies for developing neuromorphic visual system.

2.
Ying Yong Sheng Tai Xue Bao ; 34(6): 1630-1638, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37694426

ABSTRACT

Clarifying the distribution pattern and overlapping relationship of sympatric relative species in the spatio-temporal niche is important for our understanding of the behavioral relationship between species and the integrated management of multi-species habitats. Based on the infrared camera monitoring data from 2012 to 2021, we investigted the spatio-temporal distribution characteristics of the national secondary-class key protected animals Naemorhedus griseus and Capricornis milneedwardsii in the Gongga Mountain National Nature Reserve, Sichuan Province. We analyzed the distribution of N. griseuss and C. milneedwardsiis in the reserve using the MaxEnt model, based on 72 and 108 occurrence data of the two species, respectively, obtained by infrared cameras from 2016 to 2021, combined with 12 environmental factors potentially affecting their spatial distribution. Then, based on 1312 occurrence data of N. griseus and 1889 occurrence data of C. milneedwardsii collected by infrared camera from 2012 to 2021, we estimated their daily activity rhythms by using the kernel density estimation to understand the distribution pattern and overlap of the two species in the temporal niche. The results showed that the area of suitable habitats for N. griseus and C. milneedwardsii was 731.95 km2 and 1220.46 km2, respectively. The overlapping area was 697.17 km2. The main environmental factors had similar effects on the habitat selection of the two species. The daily activity of both species peaked in the early morning and evening. The utilization of the interval and intensity of the morning and evening time periods were different for the two species. The morning and evening activity peaks of C. milneedwardsii were earlier and later, respectively, than that of N. griseus. C. milneedwardsii had a higher utilization intensity during the nocturnal period. In general, high degree of spatial overlap and low degree of overlap in the temporal niche dimension contribute to the long-term coexistence of the two species.


Subject(s)
Spatial Analysis , Animals , China
3.
Nanoscale ; 15(10): 4801-4808, 2023 Mar 09.
Article in English | MEDLINE | ID: mdl-36779310

ABSTRACT

Memristors with controllable resistive switching (RS) behavior have been considered as promising candidates for synaptic devices in next-generation neuromorphic computing. In this work, two-terminal memristors with controllable digital and analog RS behavior are fabricated based on two-dimensional (2D) WSe2 nanosheets. Under a relatively high operating voltage of 4 V, the memristor demonstrates stable and reliable non-volatile bipolar digital RS with a high switching ratio of 6.3 × 104. On the other hand, under a relatively low operation voltage, the memristor exhibits analog RS with a series of tunable resistance states. The fabricated memristors can work as an artificial synapse with fundamental synaptic functions, such as long-term potentiation (LTP) and depression (LTD) as well as paired-pulse facilitation (PPF). More importantly, the memristor demonstrates high conductance modulation linearity with the calculated nonlinear parameter for conductance as -0.82 in the LTP process, which is beneficial to improving the accuracy of neuromorphic computing. Furthermore, the neuromorphic computing of file types and image recognition can be emulated based on a constructed three-layer artificial neural network (ANN) with a recognition accuracy that can reach up to 95.9% for small digits. In addition, memristors can be used to emulate the learning-forgetting experience of the human brain. Consequently, the memristor based on 2D WSe2 nanosheets not only exhibits controllable RS behavior but also simulates synaptic functions and is expected to be a potential candidate for future neuromorphic computing applications.

4.
Zhongguo Gu Shang ; 33(3): 203-8, 2020 Mar 25.
Article in Chinese | MEDLINE | ID: mdl-32233244

ABSTRACT

OBJECTIVE: To compare clinical effects of calcaneal traction and external fixator fixation of fractional delayed surgery in treating type C Pilon fractures. METHODS: From January 2012 to December 2017, clinical data of 45 patients with tibial Pilon fractures were respectively analyzed. There were 24 patients in traction group, including 16 males and 8 females, aged from 21 to 57 years old with an average age of (38.6 ±10.5) years old; 18 patients caused by falling down, 6 patients caused by traffic accident; 15 patients on the left side and 9 patients on the right side; according to AO/OTA classification, 3 patients classified type C1, 9 patients classified type C2 and 12 patients classified type C3; treated by calcaneal traction on the first stage, and open reduction and internal fixation on the second stage. There were 21 patients in external fixation group, including 15 males and 6 females, aged from 19 to 58 years old with an average age of (37.8 ±11.2) years old; 17 patients caused by falling down, 4 patients caused by traffic accident; 11 patients on the left side and 10 patients on the right side; according to AO/OTA classification, 2 patients classified type C1, 8 patients classified type C2 and 11 patients classified type C3; treated by external fixator on the first stage, and open reduction and internal fixation on the second stage. All patients were closed fracture. Preoperative waiting time, hospital stays, operative time, postoperative complications, fracture reduction and healing time between two groups were compared, VAS score was used to evaluate relief of pain before internal fixation on the second stage, Burwell-Charnley radiological evaluation criteria was applied to evaluate fracture reduction after internal fixation, AOFAS score was used to evaluate recovery of ankle joint function. RESULTS: There were no statistical difference in operative time, following-up time and fracture healing time between two groups. VAS score before internal fixation in traction group was 3.73± 0.87, while in external fixation group was 2.67±0.69, there was statistical difference between two groups. Preoperative waiting time, and hospital stays in traction group were (9.20±1.40) d ,(12.30±3.60) d; while in external fixation group were (7.60± 1.50) d ,(10.80±2.60) d; and had significant difference between two groups. There was no difference in complications between two groups. According to Burwell-Charnley radiological evaluation criteria, 20 patients obtained anatomical reduction, and 4 patients received normal reduction in traction group; 18 patients obtained anatomical reduction, and 3 patients received normal reduction in external fixation group; while without difference between two groups. There was no difference between two groups in AOFAS score. CONCLUSION: For type C Pilon fractures, one-stage calcaneus traction or temporary external fixation also could achieve temporary fixation and provide better soft tissue conditions for the second stage internal fixation, and could receive better ankle joint function after internal fixation. The operation of calcaneus traction is simple, while external fixation may be increase the number of operation times, but external fixation has more advantages in reducing preoperative pain, shortening preoperative waiting days and hospitalization time than traction.


Subject(s)
Ankle Injuries , Calcaneus , Tibial Fractures , Adult , Case-Control Studies , External Fixators , Female , Fracture Fixation , Fracture Fixation, Internal , Humans , Male , Middle Aged , Traction , Treatment Outcome , Young Adult
5.
Biomed Pharmacother ; 102: 681-688, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29604587

ABSTRACT

Nasopharyngeal carcinoma (NPC) is a type of head and neck cancers with poor prognosis. Despite that platinum-based chemotherapy concurrent with radiotherapy have made great achievements for the treatment of NPC, the therapeutic reaction and toxicity varies dramatically among individuals. Apigenin (API), a naturally occurring plant flavone, is considered to have anti-cancer effect. Cetuximab (CET), a well known epidermal growth factor receptor (EGFR) inhibitor, is widely used in various cancers, especially head and neck cancers. The aim of our study was to measure the combination of API and CET for the treatment of NPC in vitro and in vivo. Results demonstrated that combining API and CET could better suppress the viability of the human nasopharyngeal carcinoma cell lines (HONE1 and CNE2) and inhibit the growth of NPC than API or CET used alone. Besides, the combination of API with CET produced greater pro-apoptosis effect. Moreover, the increased G2/M phase arrest caused by CET could be remarkably enhanced by adding API in HONE1 and CNE2 cells. Although, both API and CET could decrease the expressions of p-EGFR, p-Akt, p-STAT3 and Cyclin D1. Combining them produced greater inhibition effect. These results suggested that the combination of API and CET may be a promising therapeutic approach for the treatment of NPC.


Subject(s)
Antineoplastic Agents/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Apigenin/therapeutic use , Carcinoma/drug therapy , Cetuximab/therapeutic use , ErbB Receptors/metabolism , Nasopharyngeal Neoplasms/drug therapy , Signal Transduction , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Apigenin/pharmacology , Apoptosis/drug effects , Carcinoma/pathology , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cetuximab/pharmacology , Humans , Male , Mice, Nude , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/pathology , Phosphorylation/drug effects , Signal Transduction/drug effects
6.
Int J Ophthalmol ; 9(7): 1020-7, 2016.
Article in English | MEDLINE | ID: mdl-27500112

ABSTRACT

AIM: To examine possible differences in clinical outcomes between sub-threshold micro-pulse diode laser photocoagulation (SDM) and traditional modified Early Treatment Diabetic Retinopathy Study (mETDRS) treatment protocol in diabetic macular edema (DME). METHODS: A comprehensive literature search using the Cochrane Collaboration methodology to identify RCTs comparing SDM with mETDRS for DME. The participants were type I or type II diabetes mellitus with clinically significant macular edema treated by SDM from previously reported randomized controlled trials (RCTs). The primary outcome measures were the changes in the best corrected visual acuity (BCVA) and the central macular thickness (CMT) as measured by optical coherence tomography (OCT). The secondary outcomes were the contrast sensitivity and the damages of the retina. RESULTS: Seven studies were identified and analyzed for comparing SDM (215 eyes) with mETDRS (210 eyes) for DME. There were no statistical differences in the BCVA after treatment between the SDM and mETDRS based on the follow-up: 3mo (MD, -0.02; 95% CI, -0.12 to 0.09; P=0.77), 6mo (MD, -0.02; 95% CI, -0.12 to 0.09; P=0.75), 12mo (MD, -0.05; 95% CI, -0.17 to 0.07; P=0.40). Likewise, there were no statistical differences in the CMT after treatment between the SDM and mETDRS in 3mo (MD, -9.92; 95% CI, -28.69 to 8.85; P=0.30), 6mo (MD, -11.37; 95% CI, -29.65 to 6.91; P=0.22), 12mo (MD, 8.44; 95% CI, -29.89 to 46.77; P=0.67). Three RCTs suggested that SDM laser results in good preservation of contrast sensitivity as mETDRS, in two different follow-up evaluations: 3mo (MD, 0.05; 95% CI, 0 to 0.09; P=0.04) and 6mo (MD, 0.02; 95% CI, -0.10 to 0.14; P=0.78). Two RCTs showed that the SDM laser treatment did less retinal damage than that mETDRS did (OR, 0.05; 95% CI, 0.02 to 0.13; P<0.01). CONCLUSION: SDM laser photocoagulation shows an equally good effect on visual acuity, contrast sensitivity, and reduction of DME as compared to conventional mETDRS protocol with less retinal damage.

7.
Luminescence ; 21(1): 20-5, 2006.
Article in English | MEDLINE | ID: mdl-16078306

ABSTRACT

A simple electrogenerated chemiluminescence (ECL) analysis method for the determination of norfloxacin (NFLX) is reported. It is based on ECL produced by Na(2)SO(3), which is sensitized by the Tb-NFLX complex. The relative ECL intensity of the Tb(3+)-NFLX-Na(2)SO(3) system is proportional to the amount of NFLX. The optimized experimental conditions were investigated. The linear range and detection limit for NFLX were 1.0 x 10(-10)-8.0 x 10(-7) mol/L and 2.8 x 10(-11) mol/L, respectively. This method was successfully applied to the determination of NFLX in a capsule. NFLX in urine can be directly detected without pretreatment or separation.


Subject(s)
Anti-Bacterial Agents/chemistry , Luminescent Measurements/methods , Norfloxacin/chemistry , Terbium/chemistry , Sulfates/chemistry
8.
Neurosci Bull ; 22(2): 115-7, 2006 Mar.
Article in English | MEDLINE | ID: mdl-17687408

ABSTRACT

Objective To explore the effect of leptin on cytokine production by PBMCs obtained from MS patients either in acute (relapse) or in stable (nonrelapse) phase of disease. Methods PBMCs were collected from 25 untreated acute MS patients, 11 stable MS patients and 20 healthy controls. PBMCs were cultured either with RPMI-1640 alone or with leptin (1.25 nmol/ml), phytohemagglutinin (PHA) (100 mug/ml), and leptin + PHA. 72 h later the supernate of the culture medium were collected and stored at -70 degrees C. The pro-inflammatory cytokine (IFN-gamma) concentration were determined using an enzyme-linked immunosorbent assay ( ELISA), and the anti-inflammatory cytokine (IL-4) concentration were investigated by radioimmunity methods. Results Our data showed that leptin induced IFN-gamma production by PBMCs of patients in an acute phase of disease but not in a stable phase or in healthy controls. Moreover, we found that PHA induced IL-4 production by PBMCs of patients in an acute phase of disease, but leptin inhibited this ability of PHA. Conclusion Leptin can affect on pro- and anti-inflammatory cytokine production by PBMCs collected from MS patients, may be this connected with leptin increase the susceptiveness of MS.

9.
Article in Chinese | MEDLINE | ID: mdl-21186594

ABSTRACT

AIM: To investigate the effect of 5-hydroxytryptamine (5-HT) on spontaneous unit discharges of primary somatosensory cortex (SI-SUD) and the role of 5-HT1A receptor in 5-HT inhibitory effect on SI-SUD in rat. METHODS: The SI-SUD was recorded before and during microiontophoresis of 5-HT and 8-OH-DPAT (the selective agonist for 5-HT1A receptor. The changes of mean of interspike interval (MISI) of SI-SUD were analysed and handled with the statistics. RESULTS: (1) Effects of 5-HT on SI-SUD may be inhibitory (48/96), excitatory (26/96) or non-responsive (22/96), and the major effect is inhibitory. (2) In 20 of 5-HT inhibited units, 17 are also inhibited with microiontophoresis of 8-OH-DPAT, but 3 have no obvious response to 8-OH-DPAT. CONCLUSION: The major effect of 5-HT on SI-SUD is inhibitory. In majority of 5-HT inhibited units, 5-HT1A receptor may be existence, which may involve in the inhibition of 5-HT on SI-SUD.


Subject(s)
8-Hydroxy-2-(di-n-propylamino)tetralin/pharmacology , Serotonin/physiology , Somatosensory Cortex/drug effects , Somatosensory Cortex/physiology , Animals , Female , Male , Rats , Rats, Wistar , Receptors, Serotonin/drug effects , Receptors, Serotonin/physiology
10.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-254592

ABSTRACT

<p><b>AIM</b>To investigate the effect of 5-hydroxytryptamine (5-HT) on spontaneous unit discharges of primary somatosensory cortex (SI-SUD) and the role of 5-HT1A receptor in 5-HT inhibitory effect on SI-SUD in rat.</p><p><b>METHODS</b>The SI-SUD was recorded before and during microiontophoresis of 5-HT and 8-OH-DPAT (the selective agonist for 5-HT1A receptor. The changes of mean of interspike interval (MISI) of SI-SUD were analysed and handled with the statistics.</p><p><b>RESULTS</b>(1) Effects of 5-HT on SI-SUD may be inhibitory (48/96), excitatory (26/96) or non-responsive (22/96), and the major effect is inhibitory. (2) In 20 of 5-HT inhibited units, 17 are also inhibited with microiontophoresis of 8-OH-DPAT, but 3 have no obvious response to 8-OH-DPAT.</p><p><b>CONCLUSION</b>The major effect of 5-HT on SI-SUD is inhibitory. In majority of 5-HT inhibited units, 5-HT1A receptor may be existence, which may involve in the inhibition of 5-HT on SI-SUD.</p>


Subject(s)
Animals , Female , Male , Rats , 8-Hydroxy-2-(di-n-propylamino)tetralin , Pharmacology , Rats, Wistar , Receptors, Serotonin , Physiology , Serotonin , Physiology , Somatosensory Cortex , Physiology
11.
Neuroscience Bulletin ; (6): 115-117, 2006.
Article in English | WPRIM (Western Pacific) | ID: wpr-300949

ABSTRACT

Objective To explore the effect of leptin on cytokine production by PBMCs obtained from MS patients either in acute (relapse) or in stable (nonrelapse) phase of disease. Methods PBMCs were collected from 25 untreated acute MS patients, 11 stable MS patients and 20 healthy controls. PBMCs were cultured either with RPMI-1640 alone or with leptin (1.25 nmol/ml), phytohemagglutinin (PHA) (100 mug/ml), and leptin + PHA. 72 h later the supernate of the culture medium were collected and stored at -70 degrees C. The pro-inflammatory cytokine (IFN-gamma) concentration were determined using an enzyme-linked immunosorbent assay ( ELISA), and the anti-inflammatory cytokine (IL-4) concentration were investigated by radioimmunity methods. Results Our data showed that leptin induced IFN-gamma production by PBMCs of patients in an acute phase of disease but not in a stable phase or in healthy controls. Moreover, we found that PHA induced IL-4 production by PBMCs of patients in an acute phase of disease, but leptin inhibited this ability of PHA. Conclusion Leptin can affect on pro- and anti-inflammatory cytokine production by PBMCs collected from MS patients, may be this connected with leptin increase the susceptiveness of MS.

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