Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 219
Filter
Add more filters

Country/Region as subject
Publication year range
1.
J Am Chem Soc ; 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38843464

ABSTRACT

Photoelectrochemical water splitting on n-type semiconductors is highly dependent on catalysis of the rate-determining reaction of O2 evolution. Conventionally, in electrochemistry and photoelectrochemistry O2 evolution is catalyzed by metal oxide catalysts like IrO2 and RuO2, whereas noble metals such as Pt are considered unsuitable for this purpose. However, our study finds that Pt, in its single-atom form, exhibits exceptional cocatalytic properties for photoelectrochemical water oxidation on a TiO2 photoanode, in contrast to Pt in a nanoparticle form. The decoration of Pt single atoms onto TiO2 yields a remarkable current density of 5.89 mA cm-2 at 1.23 VRHE, surpassing bare TiO2 (or Pt nanoparticle decorated TiO2) by 2.52 times. Notably, this enhancement remains consistent over a wide pH range. By accompanying theoretical work, we assign this significant enhancement to an improved charge transfer and separation efficiency along with accelerated kinetics in the oxygen evolution reaction facilitated by the presence of Pt single atoms on the TiO2 surface.

2.
BMC Anesthesiol ; 24(1): 137, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38600490

ABSTRACT

BACKGROUND: With the increasing prevalence of colorectal cancer (CRC), optimizing perioperative management is of paramount importance. This study investigates the potential of stellate ganglion block (SGB), known for its stress response-mediating effects, in improving postoperative recovery. We postulate that preoperative SGB may enhance the postoperative recovery of patients undergoing laparoscopic CRC surgery. METHODS: We conducted a randomized controlled trial of 57 patients undergoing laparoscopic colorectal cancer surgery at a single center. Patients, aged 18-70 years, were randomly assigned to receive either preoperative SGB or standard care. SGB group patients received 10 mL of 0.2% ropivacaine under ultrasound guidance prior to surgery. Primary outcome was time to flatus, with secondary outcomes encompassing time to defecation, lying in bed time, visual analog scale (VAS) pain score, hospital stays, patient costs, intraoperative and postoperative complications, and 3-year mortality. A per-protocol analysis was used. RESULTS: Twenty-nine patients in the SGB group and 28 patients in the control group were analyzed. The SGB group exhibited a significantly shorter time to flatus (mean [SD] hour, 20.52 [9.18] vs. 27.93 [11.69]; p = 0.012), accompanied by decreased plasma cortisol levels (mean [SD], postoperatively, 4.01 [3.42] vs 7.75 [3.13], p = 0.02). Notably, postoperative pain was effectively managed, evident by lower VAS scores at 6 h post-surgery in SGB-treated patients (mean [SD], 4.70 [0.91] vs 5.35 [1.32]; p = 0.040). Furthermore, patients in the SGB group experienced reduced hospital stay length (mean [SD], day, 6.61 [1.57] vs 8.72 [5.13], p = 0.042). CONCLUSIONS: Preoperative SGB emerges as a promising approach to enhance the postoperative recovery of patients undergoing laparoscopic CRC surgery. CLINICAL TRIAL REGISTRATION: ChiCTR1900028404, Principal investigator: Xia Feng, Date of registration: 12/20/2019.


Subject(s)
Colorectal Neoplasms , Colorectal Surgery , Laparoscopy , Humans , Stellate Ganglion , Flatulence/complications , Double-Blind Method , Pain, Postoperative/epidemiology , Pain, Postoperative/prevention & control , Pain, Postoperative/drug therapy , Laparoscopy/adverse effects , Colorectal Neoplasms/surgery , Ultrasonography, Interventional
3.
Chem Soc Rev ; 52(2): 779-794, 2023 Jan 25.
Article in English | MEDLINE | ID: mdl-36541179

ABSTRACT

Major advances in molecular detection are being driven by goals associated with the development of methods that are amenable to miniaturization and automation, and that have high sensitivity and low interference. The new detection methods are confronted by many interfacial issues, which when properly addressed can lead to improved performance. One interfacial property, special wettability, can facilitate precise delivery and local enrichment of molecules to sensing elements. This review summarizes applications of unique features of special wettability in molecular detection including (1) chemical and electrochemical reactions in anchored microdroplets on superwetting surfaces, (2) enrichment of analytes and active materials at low contact areas between droplets and superwetting surfaces, (3) complete opposite affinities of superwetting surfaces toward nonpolar/polar solutes and oil/water phases, and (4) directional droplet transportation on asymmetric superwetting surfaces. The challenges and opportunities that exist in design and applications of special wettability in interfacial delivery and enrichment for detection of a few molecules are also discussed.

4.
Nano Lett ; 23(16): 7371-7378, 2023 Aug 23.
Article in English | MEDLINE | ID: mdl-37534973

ABSTRACT

Hierarchical assembly of arc-like fractal nanostructures not only has its unique self-similarity feature for stability enhancement but also possesses the structural advantages of highly exposed surface-active sites for activity enhancement, remaining a great challenge for high-performance metallic nanocatalyst design. Herein, we report a facile strategy to synthesize a novel arc-like hierarchical fractal structure of PtPd bimetallic nanoparticles (h-PtPd) by using pyridinium-type ionic liquids as the structure-directing agent. Growth mechanisms of the arc-like nanostructured PtPd nanoparticles have been fully studied, and precise control of the particle sizes and pore sizes has been achieved. Due to the structural features, such as size control by self-similarity growth of subunits, structural stability by nanofusion of subunits, and increased numbers of exposed active atoms by the curved homoepitaxial growth, h-PtPd displays outstanding electrocatalytic activity toward oxygen reduction reaction and excellent stability during hydrothermal treatment and catalytic process.

5.
Nano Lett ; 23(3): 1052-1060, 2023 Feb 08.
Article in English | MEDLINE | ID: mdl-36706048

ABSTRACT

Efficient and stable electrocatalysts are critically needed for the development of practical overall seawater splitting. The nanocomposite of RuCoBO has been rationally engineered to be an electrocatalyst that fits these criteria. The study has shown that a calcinated RuCoBO-based nanocomposite (Ru2Co1BO-350) exhibits an extremely high catalytic activity for H2 and O2 production in alkaline seawater (overpotentials of 14 mV for H2 evolution and 219 mV for O2 evolution) as well as a record low cell voltage (1.466 V@10 mA cm-2) and long-term stability (230 h @50 mA cm-2 and @100 mA cm-2) for seawater splitting. The results show that surface reconstruction of Ru2Co1BO-350 occurs during hydrogen evolution reaction and oxygen evolution reaction, which leads to the high activity and stability of the catalyst. The reconstructed surface is highly resistant to Cl- corrosion. The investigation suggests that a new strategy exists for the design of high-performance Ru-based electrocatalysts that resist anodic corrosion during seawater splitting.

6.
Nano Lett ; 23(10): 4390-4398, 2023 May 24.
Article in English | MEDLINE | ID: mdl-37154763

ABSTRACT

Photocatalysts for seawater splitting are severely restricted because of the presence of multiple types of ions in seawater that cause corrosion and deactivation. As a result, new materials that promote adsorption of H+ and hinder competing adsorption of metal cations should enhance utilization of photogenerated electrons on the catalyst surface for efficient H2 production. One strategy to design advanced photocatalysts involves introduction of hierarchical porous structures that enable fast mass transfer and creation of defect sites that promote selective hydrogen ion adsorption. Herein, we used a facile calcination method to fabricate the macro-mesoporous C3N4 derivative, VN-HCN, that contains multiple nitrogen vacancies. We demonstrated that VN-HCN has enhanced corrosion resistance and elevated photocatalytic H2 production performance in seawater. Experimental results and theoretical calculations reveal that enhanced mass and carrier transfer and selective adsorption of hydrogen ions are key features of VN-HCN that lead to its high seawater splitting activity.

7.
Small ; 19(33): e2301279, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37086130

ABSTRACT

The combination of hetero-elemental doping and vacancy engineering will be developed as one of the most efficient strategies to design excellent electrocatalysts for hydrogen evolution reaction (HER). Herein, a novel strategy for N-doping coupled with Co-vacancies is demonstrated to precisely activate inert S atoms adjacent to Co-vacancies and significantly improve charge transfer for CoS toward accelerating HER. In this strategy, N-doping favors the presence of Co-vacancies, due to greatly decreasing their formation energy. The as-developed strategy realizes the upshift of S 3p orbitals followed by more overlapping between S 3py and H 1s orbitals, which results in the favorable hydrogen atom adsorption free energy change (ΔGH ) to activate inert S atoms as newborn catalytical sites. Besides, this strategy synergistically decreases the bandgap of CoS, thereby achieving satisfactory electrical conductivity and low charge-transfer resistance for the as-obtained electrocatalysts. With an excellent HER activity of -89.0 mV at 10.0 mA cm-2 in alkaline environments, this work provides a new approach to unlocking inert sites and significantly improving charge transfer toward cobalt-based materials for highly efficient HER.

8.
Chemistry ; 29(5): e202202811, 2023 Jan 24.
Article in English | MEDLINE | ID: mdl-36321591

ABSTRACT

A solvothermal method to prepare PtNi alloys that have differing morphologies is described. By adjusting the feed ratio of Pt and Ni precursors in this process, PtNi alloys with different compositions (Pt : Ni atomic ratio from 1 : 3 to 3 : 1) and morphologies (evolution from nanobranches to nanoparticles) are generated. The prepared Pt48 Ni52 alloy, which has a composite morphology comprised of nanobranches and nanoparticles, exhibits superior activity and durability towards the hydrogen evolution reaction (HER) in seawater compared to those of commercial Pt/C catalyst and other PtNi alloys that have different compositions and morphologies. The excellent seawater HER performance of Pt48 Ni52 is ascribed to its nanobranch/nanoparticle morphology that optimally facilitates electron accumulation on Pt, which enhances resistance to chloride corrosion in seawater.


Subject(s)
Alloys , Chlorides , Corrosion , Halogens , Hydrogen , Seawater
9.
Chemistry ; 29(18): e202203662, 2023 Mar 28.
Article in English | MEDLINE | ID: mdl-36598845

ABSTRACT

CdS nanoparticles were introduced on E. coli cells to construct a hydrogen generating biohybrid system via the biointerface of tannic acid-Fe complex. This hybrid system promotes good biological activity in a high salinity environment. Under light illumination, the as-synthesized biohybrid system achieves a 32.44 % enhancement of hydrogen production in seawater through a synergistic effect.


Subject(s)
Escherichia coli , Nanoparticles , Semiconductors , Hydrogen
10.
Langmuir ; 39(15): 5375-5383, 2023 Apr 18.
Article in English | MEDLINE | ID: mdl-36951389

ABSTRACT

Many attempts have been made to enhance the relatively poor electrochemical activity of Ni3S2 for the oxygen evolution reaction (OER) by elevating the d-band center. Unfortunately, only limited success has been encountered thus far. Owning to the lower electronegativity and one less 3d electron relative to Ni, Fe shows great potentials in upshifting the overall d-band center of Ni3S2 when incorporating into its crystal structures. Herein, to enhance the intrinsic activity by elevating the d-band center, Ni3S2 nanosheets incorporated with suitable Fe content have been fabricated by a facile one-step solvothermal method. The obtained Fe-incorporated Ni3S2 catalyst exhibits an outstanding OER performance in alkaline media, only requiring 244 mV overpotential (with a reduction of 210 mV compared to Ni3S2) at 50 mA cm-2 in 1 M KOH and without obvious degradation after sustaining for a 60 h test at a voltage above 1.5 V. Ultraviolet photoemission spectroscopy and density functional theory calculations consistently demonstrate that the superior performance of Fe-incorporated Ni3S2 is attributed to the upshift of the d-band center on neutralizing the electron densities of Ni, which optimize greatly the adsorption energy of the intermediate (OOH*) in the rate-determining Volmer step.

11.
Langmuir ; 39(1): 236-248, 2023 Jan 10.
Article in English | MEDLINE | ID: mdl-36525334

ABSTRACT

Besides improving charge transfer, there are two key factors, such as increasing active sites and promoting water dissociation, to be deeply investigated to realize high-performance MoS2-based electrocatalysts in alkaline hydrogen evolution reaction (HER). Herein, we have demonstrated the synergistic engineering to realize rich unsaturated sulfur atoms and activated O-H bonds toward the water for Ni-doped MoS2/CoS2 hierarchical structures by an approach to Ni doping coupled with in situ sulfurizing for excellent alkaline HER. In this work, the Ni-doped atoms are evolved into Ni(OH)2 during alkaline HER. Interestingly, the extra unsaturated sulfur atoms will be modulated into MoS2 nanosheets by breaking Ni-S bonds during the formation of Ni(OH)2. On the other hand, the higher the mass of the Ni precursor (mNi) for the fabrication of our samples, the more Ni(OH)2 is evolved, indicating a stronger ability for water dissociation of our samples during alkaline HER. Our results further reveal that regulating mNi is crucial to the HER activity of the as-synthesized samples. By regulating mNi to 0.300 g, a balance between increasing active sites and promoting water dissociation is achieved for the Ni-doped MoS2/CoS2 samples to boost alkaline HER. Consequently, the optimal samples present the highest HER activity among all counterparts, accompanied by reliable long-term stability. This work will promise important applications in the field of electrocatalytic hydrogen evolution in alkaline environments.

12.
J Liposome Res ; 33(2): 144-153, 2023 Jun.
Article in English | MEDLINE | ID: mdl-35875973

ABSTRACT

OBJECTIVE: To investigate the preparation of novel nanoliposomes (Borneol Angelica Polysaccharide Liposomes, BAPL) for anti-cerebral ischaemia and verify its curative effects and mechanism. METHODS: By applying a uniform experiment design to investigate the fitting combination of BAPL. Encapsulation Efficiency Evaluation of BAPL Preparation; Particle Size and Surface Potential Evaluation of BAPL Biological activity; Cerebral ischaemia models of rats Evaluation of BAPL curative effects and mechanism. RESULTS: (1) The fitting combination of lecithin, Cholesterol, AP mass and the borneol mass was 60 mg, 60 mg, 45 mg and 5 mg. the highest encapsulation efficiency was 80.4%, the particle size was 179.1 nm, and the surface zeta potential was -17.2 mV. It conforms to the nano-material standards. (2) The results of animal experiments show that: In the BAPL group, the infarct volume of TTC staining was significantly decreased, and the expression levels of NF-κBp65, TLR-4, IL-8, IL-6, IL-1ß in brain tissue were significantly decreased, while the expression levels of ZO-1, ZO-2, IL-10 were significantly increased after cerebral ischaemia-reperfusion. CONCLUSION: BAPL is a novel nano and effective material for anti-cerebral ischaemia.


Subject(s)
Brain Ischemia , Liposomes , Rats , Animals , Brain Ischemia/drug therapy , Ischemia , Polysaccharides/pharmacology
13.
Int Wound J ; 20(2): 516-528, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36008920

ABSTRACT

Radiodermatitis is an inevitable side effect of radiotherapy in cancer treatment and there is currently no consensus on effective drugs for treating the condition. Vitamin B12 is known to be effective for repairing and regenerating damaged skin. However, there are few studies on the use of Vitamin B12 for treating radiodermatitis. This study explored the therapeutic efficacy and mechanism of action of Vitamin B12 ointment on radiodermatitis. A porcine model of grade IV radiodermatitis was established. The ointment was applied for 12 weeks after which histological staining, transmission electron microscopy, RT-qPCR, western blotting, and gene sequencing were performed for the evaluation of specific indicators in skin samples. After 12 weeks of observation, the Vitamin B12 treatment was found to have significantly alleviated radiodermatitis. The treatment also significantly reduced the expression levels of NF-κB, COX-2, IL-6, and TGF-ß in the skin samples. The pathways involved in the effects of the treatment were identified by analysing gene expression. In conclusion, Vitamin B12 ointment was found to be highly effective for treating radiodermatitis, with strong anti-radiation, anti-inflammatory, and anti-fibrosis effects. It is thus a promising drug candidate for the treatment of severe radiodermatitis.


Subject(s)
Radiodermatitis , Animals , Swine , Radiodermatitis/drug therapy , Ointments/therapeutic use , Vitamin B 12/therapeutic use , Administration, Topical , Anti-Inflammatory Agents/therapeutic use , Vitamins/therapeutic use
14.
Zhonghua Nan Ke Xue ; 29(1): 43-48, 2023 Jan.
Article in Zh | MEDLINE | ID: mdl-37846831

ABSTRACT

OBJECTIVE: To investigate the outcomes of intracytoplasmic sperm injection (ICSI) in the treatment of special types of teratozoospermia such as globozoospermia, acephalic spermatozoa syndrome (ASS) and multiple morphological abnormalities of sperm flagella (MMAF). METHODS: We retrospectively analyzed the clinical data on 7 cases of globozoospermia (group A), 6 cases of ASS (group B) and 21 cases of MMAF (group C) treated by ICSI from January 2011 to January 2021, all confirmed with pathogenic or likely pathogenic gene variations. We compared the age, body mass index (BMI), sperm parameters, number of mature oocytes, and rates of fertilization, high-quality embryos, clinical pregnancy, live birth and spontaneous abortion among the three groups of patients. RESULTS: There were no statistically significant differences in the age, BMI and number of metaphase Ⅱ (MⅡ) oocytes among the three groups (P > 0.05). Sperm concentration and motility were dramatically higher (P < 0.01) while the rates of fertilization, clinical pregnancy and live birth remarkably lower in group A than in B and C (P < 0.01). No statistically significant difference was observed in the spontaneous abortion rate among the three groups (P > 0.05). CONCLUSION: ICSI can achieve relatively satisfactory outcomes of clinical pregnancy in patients with ASS or MMAF, but only a low fertilization rate or no fertilization at all in those with globozoospermia even if treated by artificial oocyte activation.


Subject(s)
Abortion, Spontaneous , Infertility, Male , Teratozoospermia , Pregnancy , Female , Humans , Male , Sperm Injections, Intracytoplasmic , Teratozoospermia/genetics , Infertility, Male/genetics , Retrospective Studies , Semen , Spermatozoa , Oocytes
15.
Zhonghua Nan Ke Xue ; 29(9): 804-809, 2023 Sep.
Article in Zh | MEDLINE | ID: mdl-38639592

ABSTRACT

OBJECTIVE: Preimplantation genetic testing (PGT) was performed to analyze the embryo euploidy in patients with complete Y chromosome AZFc microdeletion. METHODS: The clinical data of complete AZFc microdeletion underwent PGT from January 2013 to December 2021 in Reproductive Medicine Center of the First Affiliated Hospital of Nanjing Medical University were retrospectively analyzed. The patients with monogenic disease who underwent PGT during the same period were set as the control group. The basic characteristics, fertilization rate, Day 3 high quality embryo rate, blastocyst formation rate, embryo euploid rate, 45, X embryo ratio was compared between the two groups. RESULTS: A total of 220 patients were included, including 91 patients with complete AZFc microdeletion and 129 patients with monogenic disease. There was no significant difference in age between the two groups. In semen parameters, the sperm concentration, total sperm count and progressive motility in AZFc microdeletion group were lower than those in monogenic disease group, and the differences were statistically significant (P=0.001). The fertilization rate of AZFc microdeletion group was lower than that in monogenic disease group (P=0.012), and there was no significant difference in the number of MII oocytes, Day 3 high-quality embryo rate and blastocyst formation rate. A total of 933 blastocysts were successfully tested, including 496 blastocysts in AZFc deletion group and 437 blastocysts in monogenic disease group. The euploid, aneuploid and mosaic rates of the AZFc microdeletion group were 57.26%, 24.60% and 18.14%, respectively, while those of the monogenic disease group were 66.13%, 23.80% and 10.07%, with statistically significant differences between the two groups (P=0.001). Further analysis of the two groups of aneuploid embryos showed that aberrations occurred most commonly in chromosome16 (3.87%), X (3.46%), 13 (2.44%), 22 (2.24%) and 19 (2.03%) in AZFc microdeletion group, respectively, while the monogenic disease group was 22 (4.35%), 16 (2.97%), 7 (2.74%), 15(1.60%) and 2(1.60%), respectively. The proportion of sex chromosome abnormality in AZFc microdeletion group was higher than that in monogenic disease group (P=0.039), and there was no significant difference in the proportion of 45,X between the two groups. CONCLUSION: Compared with monogenic disease group, The embryo euploid rate in AZFc microdeletion patients decreased and the proportion of 45, X embryos did not increase significantly. It is recommended to select euploid female embryos by PGT, which not only avoids vertical transmission of AZFc microdeletion, but also reduces the risk of miscarriage due to aneuploid embryos.


Subject(s)
Preimplantation Diagnosis , Pregnancy , Humans , Male , Female , Retrospective Studies , Semen , Aneuploidy , Genetic Testing , Blastocyst , Y Chromosome
16.
Zhonghua Nan Ke Xue ; 29(10): 922-927, 2023 Oct.
Article in Zh | MEDLINE | ID: mdl-38639663

ABSTRACT

OBJECTIVE: To study the correlation, consistency, and variations between two assays of DNA fragmentation index based on acridine orange (AO) staining via AI-based fluorescence microscopy(AI-DFI), and flow cytometry (FCM-DFI) across multiple centers. METHODS: We selected 421 male patients from Nanjing Drum Tower hospital ( Hospital G) (226 cases), Eastern Theatre General Hospital (Hospital J) (89 cases) and Jiangsu Province Hospital (Hospital S) (106 cases) . Semen samples from each patient were analyzed for routine semen parameters and for DFI using both AI fluorescence microscopy and flow cytometry. We studied the two methods' stability as well as the correlation, consistency, and variation between the two methods' results in various centers. RESULTS: The two replicate studies' results of AI-DFI and the three centers' FCM-DFI for linear regression analysis indicated strong stability (R2>0.9).Overall(Group A), the AI-DFI results demonstrated good correlation and consistency with the FCM-DFI results of three centers (r>0.85;ICC>0.9).The semen specimens were categorized into two groups: normal specimen group (group B) and abnormal specimen group (group C) (including asthenozoospermia, oligospermia, and semen samples with high impurities).Group C's results showed a decline in correlation and consistency when compared to group A and group B, whereas group B's results showed a little rise in correlation and consistency when compared to group A. Although the consistency and correlation between the results of the two DFI testing methods in the three centers were good, there was still a significant difference between Groups A and C (P<0.05), and in Group B there was a significant difference between the two DFI testing methods only in Hospital G (p=0.02), with no significant difference in Hospitals J and S (P> 0.05). CONCLUSION: The two detection methods exhibit good stability and correlation. However, significant differences are observed in the DFI detection methods in samples with abnormal semen parameters and high complexity. The main reason for these significant differences may lie in the variations in detection principles. Each detection method has its own advantages, allowing clinical or research settings to choose between them based on laboratory conditions or specific requirements.


Subject(s)
Infertility, Male , Semen , Humans , Male , Semen Analysis/methods , Flow Cytometry/methods , DNA Fragmentation , Spermatozoa , Microscopy, Fluorescence , Staining and Labeling , Artificial Intelligence , Infertility, Male/diagnosis , Infertility, Male/genetics
17.
Small ; 18(42): e2203778, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36103609

ABSTRACT

An electrocatalyst composed of RuO2 surrounded by interfacial carbon, is synthesized through controllable oxidization-calcination. This electrocatalyst provides efficient charge transfer, numerous active sites, and promising activity for pH-universal electrocatalytic overall seawater splitting. An electrolyzer with this catalyst gives current densities of 10 mA cm-2 at a record low cell voltage of 1.52 V, and shows excellent durability at current densities of 10 mA cm-2 for up to 100 h. Based on the results, a mechanism for the catalytic activity of the composite is proposed. Finally, a solar-driven system is assembled and used for overall seawater splitting, showing 95% Faraday efficiency.

18.
Eur J Anaesthesiol ; 39(9): 758-765, 2022 09 01.
Article in English | MEDLINE | ID: mdl-35919026

ABSTRACT

BACKGROUND: Identifying the interscalene brachial plexus can be challenging during ultrasound-guided interscalene block. OBJECTIVE: We hypothesised that an algorithm based on deep learning could locate the interscalene brachial plexus in ultrasound images better than a nonexpert anaesthesiologist, thus possessing the potential to aid anaesthesiologists. DESIGN: Observational study. SETTING: A tertiary hospital in Shanghai, China. PATIENTS: Patients undergoing elective surgery. INTERVENTIONS: Ultrasound images at the interscalene level were collected from patients. Two independent image datasets were prepared to train and evaluate the deep learning model. Three senior anaesthesiologists who were experts in regional anaesthesia annotated the images. A deep convolutional neural network was developed, trained and optimised to locate the interscalene brachial plexus in the ultrasound images. Expert annotations on the datasets were regarded as an accurate baseline (ground truth). The test dataset was also annotated by five nonexpert anaesthesiologists. MAIN OUTCOME MEASURES: The primary outcome of the research was the distance between the lateral midpoints of the nerve sheath contours of the model predictions and ground truth. RESULTS: The data set was obtained from 1126 patients. The training dataset comprised 11 392 images from 1076 patients. The test dataset constituted 100 images from 50 patients. In the test dataset, the median [IQR] distance between the lateral midpoints of the nerve sheath contours of the model predictions and ground truth was 0.8 [0.4 to 2.9] mm: this was significantly shorter than that between nonexpert predictions and ground truth (3.4 mm [2.1 to 4.5] mm; P < 0.001). CONCLUSION: The proposed model was able to locate the interscalene brachial plexus in ultrasound images more accurately than nonexperts. TRIAL REGISTRATION: ClinicalTrials.gov (https://clinicaltrials.gov) identifier: NCT04183972.


Subject(s)
Brachial Plexus Block , Brachial Plexus , Anesthetics, Local , Artificial Intelligence , Brachial Plexus/diagnostic imaging , Brachial Plexus Block/methods , China , Humans , Neural Networks, Computer , Ultrasonography, Interventional/methods
19.
Nano Lett ; 21(18): 7870-7878, 2021 09 22.
Article in English | MEDLINE | ID: mdl-34318680

ABSTRACT

Fractal Pt-based materials with hierarchical structures and high self-similarity have attracted more and more attention due to their bioinspiring maximum optimization of energy utilization and mass transfer. However, their high-efficiency design of the mass- and electron-transfer still remains to be a great challenge. Herein, fractal PtPdCu hollow sponges (denoted as PtPdCu-HS) facilitating both directed mass- and electron-transfer are presented. Such directed transfer effects greatly promote electrocatalytic activity, regarded as 3.9 times the mass activity, 7.3 times the specific activity, higher poison tolerance, and higher stability than commercial Pt/C for the methanol oxidation reaction (MOR). A new "directed mass- and electron-transfer" concept, characteristics, and mechanism are proposed at the micro/nanoscale to clarify the structural design and functional enhancement of fractal electrocatalyst. This work displays new possibilities for designing novel nanomaterials with high activity and superior stability toward electrocatalysis or other practical applications.


Subject(s)
Electrons , Fractals , Catalysis , Electron Transport , Oxidation-Reduction
20.
Small ; 17(22): e2002811, 2021 Jun.
Article in English | MEDLINE | ID: mdl-32734686

ABSTRACT

Carbon-based nanomaterials have been widely utilized in catalysis and energy-related fields due to their fascinating properties. However, the controllable synthesis of porous carbon with refined morphology is still a formidable challenge due to inevitable aggregation/fusion of resulted carbon particles during the high-temperature synthetic process. Herein, a hierarchically oriented carbon-structured (fiber-like) composite is fabricated by simultaneously taking advantage of a confined pyrolysis strategy and disparate bond environments within metal-organic frameworks (MOFs). In the resultant composite, the oriented carbon provides a fast mass (molecule/ion/electron) transfer efficiency; the doping-N atoms can anchor or act as active sites; the mesoporous SiO2 (mSiO2 ) shell not only effectively prevents the derived carbon or active metal nanoparticles (NPs) from aggregation or leaching, but also acts as a "polysulfide reservoir" in the Li-S batteries to suppress the "shuttle" effect. Benefiting from these advantages, the synthesized composite Pd@NDHPC@mSiO2 (NDHPC means N-doped hierarchically porous carbon) exhibits extremely high catalytic activity and stability toward the one-pot Knoevenagel condensation-hydrogenation reaction. Furthermore, the oriented NDHPC@mSiO2 manifests a boosted capacity and cycling stability in Li-S batteries compared to the counterpart that directly pyrolyzes without silica protection. This report provides an effective strategy of fabricating hierarchically oriented carbon composites for catalysis and energy storage applications.

SELECTION OF CITATIONS
SEARCH DETAIL