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1.
Biodivers Data J ; 12: e122325, 2024.
Article in English | MEDLINE | ID: mdl-38827585

ABSTRACT

Cinnamomumparthenoxylon (Jack) Meisn. is a tree in genus Cinnamomum that has been facing global threats due to forest degradation and habitat fragmentation. Many recent studies aim to describe habitats and assess population and species genetic diversity for species conservation by expanding afforestation models for this species. Understanding their current and future potential distribution plays a major role in guiding conservation efforts. Using five modern machine-learning algorithms available on Google Earth Engine helped us evaluate suitable habitats for the species. The results revealed that Random Forest (RF) had the highest accuracy for model comparison, outperforming Support Vector Machine (SVM), Classification and Regression Trees (CART), Gradient Boosting Decision Tree (GBDT) and Maximum Entropy (MaxEnt). The results also showed that the extremely suitable ecological areas for the species are mostly distributed in northern Vietnam, followed by the North Central Coast and the Central Highlands. Elevation, Temperature Annual Range and Mean Diurnal Range were the three most important parameters affecting the potential distribution of C.parthenoxylon. Evaluation of the impact of climate on its distribution under different climate scenarios in the past (Last Glacial Maximum and Mid-Holocene), in the present (Worldclim) and in the future (using four climate change scenarios: ACCESS, MIROC6, EC-Earth3-Veg and MRI-ESM2-0) revealed that of C.parthenoxylon would likely expand to the northeast, while a large area of central Vietnam will gradually lose its adaptive capacity by 2100.

2.
Small ; : e2402074, 2024 May 25.
Article in English | MEDLINE | ID: mdl-38794990

ABSTRACT

The high theoretical energy density (2600 Wh kg-1) and low cost of lithium-sulfur batteries (LSBs) make them an ideal alternative for the next-generation energy storage system. Nevertheless, severe capacity degradation and low sulfur utilization resulting from shuttle effect hinder their commercialization. Herein, Single-atom Ru-doped 1T/2H MoS2 with enriched defects decorates V2C MXene (Ru-MoS2/MXene) produced by a new phase-engineering strategy employed as sulfur host to promote polysulfide adsorption and conversion reaction kinetics. The Ru single atom-doped adjusts the chemical environment of the MoS2/MXene to anchor polysulfide and acts as an efficient center to motivate the redox reaction. In addition, the rich defects of the MoS2 and ternary boundary among 1T/2H MoS2 and V2C accelerate the charge transfer and ion movements for the reaction. As expected, the Ru-MoS2/MXene/S cathode-based cell exhibits a high-rate capability of 684.3 mAh g-1 at 6 C. After 1000 cycles, the Ru-MoS2/MXene/S cell maintains an excellent cycling stability of 696 mAh g-1 at 2 C with a capacity degradation as low as 0.02% per cycle. Despite a high sulfur loading of 9.5 mg cm-2 and a lean electrolyte-to-sulfur ratio of 4.3, the cell achieves a high discharge capacity of 726 mAh g-1.

3.
Small ; 19(11): e2206726, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36599644

ABSTRACT

The development of trifunctional electrocatalyst for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER) with deeply understanding the mechanism to enhance the electrochemical performance is still a challenging task. In this work, the distorted metastable hybrid-phase induced 1T'/1T Co,PSnS2 nanosheets on carbon cloth (1T'/1T Co,PSnS2 @CC) is prepared and examined. The density functional theoretical (DFT) calculation suggests that the distorted 1T'/1T Co,PSnS2 can provide excellent conductivity and strong hydrogen adsorption ability. The electronic structure tuning and enhancement mechanism of electrochemical performance are investigated and discussed. The optimal 1T'/1T Co,PSnS2 @CC catalyst exhibits low overpotential of ≈94 and 219.7 mV at 10 mA cm-2 for HER and OER, respectively. Remarkably, the catalyst exhibits exceptional ORR activity with small onset potential value (≈0.94 V) and half-wave potential (≈0.87 V). Most significantly, the 1T'/1T Co,PSnS2 ||Co,PSnS2 electrolyzer required small cell voltages of ≈1.53, 1.70, and 1.82 V at 10, 100, and 400 mA cm-2 , respectively, which are better than those of state-of-the-art Pt-C||RuO2 (≈1.56 and 1.84 V at 10 and 100 mA cm-2 ). The present study suggests a new approach for the preparation of large-scalable, high performance hierarchical 3D next-generation trifunctional electrocatalysts.

4.
Small ; 19(10): e2206341, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36650925

ABSTRACT

Rechargeable zinc-air batteries (ZABs) are promising energy storage systems due to their low-cost and safety. However, the working principle of ZABs is based on oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), which display sluggish kinetic and low stability. Herein, this work proposes a novel method to design a heterogeneous CoP/CoO electrocatalyst on mesopore nanobox carbon/carbon nanotube (CoP/CoO@MNC-CNT) that enriched active sites and synergistic effect. Moreover, the well-defined heterointerfaces could lower the energy barrier for intermediate species adsorption and promote OER and ORR electrochemical performances. The CoP/CoO@MNC-CNT electrocatalyst presents a high half-wave potential of 0.838 V for ORR and a small overpotential of 270 mV for OER. The ZABs-based CoP/CoO@MNC-CNT air-cathode shows an open-circuit voltage of 1.409 V, the long-term cycle life of 500 h with a small voltage difference change of 7.7%. Additionally, the flexible ZABs exhibit highly mechanical stability, demonstrating their application potential in wearable electronic devices.

5.
Chemosphere ; 307(Pt 2): 135870, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35921886

ABSTRACT

Metal-free carbonaceous catalysts have gained growing interest because of their excellence in organic pollutant degradation. However, most of them suffer from deactivation after use, and the origins have not been investigated or understood. In this study, the changes in the characteristics after multiple uses of a carbonaceous catalyst, i.e., oxygen-doped graphitic carbon nitride (O-gCN), were investigated to identify the key factors affecting its reactivity. The O-gCN was repeatedly used to remove an antibiotic (oxytetracycline, OTC) in the presence of peroxymonosulfate (PMS). OTC removal was significantly reduced as the O-gCN was repeatedly used. The reactivity of O-gCN used five times (O-gCN5) corresponded well with the decreased signals of DMPO-X, DMPO-O2•-, and TEMP-1O2 in electron paramagnetic resonance spectra. These signal changes were accompanied by a shift of the involved reactive species from 1O2 and OH• for O-gCN to 1O2 and SO4•- for O-gCN5. The changes in activity and involved reactive species were attributed to the changes in the properties of O-gCN, considering the negligible OTC adsorption and slight PMS consumption. The results of X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy showed a decrease in the degree of defects, graphene-like layers, and crystallinity in graphitic structures, but an increase in the fractions of N and O, for O-gCN5. However, the OTC degradation pathways and intermediates were not significantly different for O-gCN and O-gCN5. These results provide valuable information for developing strategies for the design, practical use, and regeneration of carbonaceous catalysts.


Subject(s)
Environmental Pollutants , Graphite , Oxytetracycline , Anti-Bacterial Agents , Nitrogen Compounds , Oxygen , Peroxides
6.
World J Clin Cases ; 9(31): 9670-9679, 2021 Nov 06.
Article in English | MEDLINE | ID: mdl-34877305

ABSTRACT

BACKGROUND: Brunner's gland hyperplasia (BGH) is a rare benign lesion of the duodenum. Lipomatous pseudohypertrophy (LiPH) of the pancreas is an extremely rare disease. Because each condition is rare, the probability of purely coincidental coexistence of both conditions is extremely low. CASE SUMMARY: We report a 26-year-old man presenting to our hospital with symptoms of recurrent upper gastrointestinal bleeding. Upper gastrointestinal endoscopy showed a huge pedunculated polypoid lesion in the duodenum with bleeding at the base of the lesion. Histopathological examination of the duodenal biopsy specimens showed BGH. Besides, abdominal computed tomography and magnetic resonance imaging revealed marked fat replacement over the entire pancreas, confirmed by histopathological evaluation on percutaneous pancreatic biopsies. Based on the radiological and histological findings, LiPH of the pancreas and BGH were diagnosed. The patient refused any surgical intervention. Therefore, he was managed with supportive treatment. The patient's symptoms improved and there was no further bleeding. CONCLUSION: This is the first well-documented case showing the coexistence of LiPH of the pancreas and BGH.

7.
Healthcare (Basel) ; 9(1)2021 Jan 06.
Article in English | MEDLINE | ID: mdl-33419018

ABSTRACT

Deep learning is one of the most effective approaches to medical image processing applications. Network models are being studied more and more for medical image segmentation challenges. The encoder-decoder structure is achieving great success, in particular the Unet architecture, which is used as a baseline architecture for the medical image segmentation networks. Traditional Unet and Unet-based networks still have a limitation that is not able to fully exploit the output features of the convolutional units in the node. In this study, we proposed a new network model named TMD-Unet, which had three main enhancements in comparison with Unet: (1) modifying the interconnection of the network node, (2) using dilated convolution instead of the standard convolution, and (3) integrating the multi-scale input features on the input side of the model and applying a dense skip connection instead of a regular skip connection. Our experiments were performed on seven datasets, including many different medical image modalities such as colonoscopy, electron microscopy (EM), dermoscopy, computed tomography (CT), and magnetic resonance imaging (MRI). The segmentation applications implemented in the paper include EM, nuclei, polyp, skin lesion, left atrium, spleen, and liver segmentation. The dice score of our proposed models achieved 96.43% for liver segmentation, 95.51% for spleen segmentation, 92.65% for polyp segmentation, 94.11% for EM segmentation, 92.49% for nuclei segmentation, 91.81% for left atrium segmentation, and 87.27% for skin lesion segmentation. The experimental results showed that the proposed model was superior to the popular models for all seven applications, which demonstrates the high generality of the proposed model.

8.
Small ; 16(48): e2004661, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33169511

ABSTRACT

Highly flexible quasi solid-state batteries are promising in next-generation energy storage sectors due to their high energy density, power density, and low manufacturing cost. However, poor cycle life seriously limits their application in industrial sectors. Herein, a novel strategy is established to design the oxygenated cobalt vanadium selenide (O-Cox V1- x Se2 ) nanostructures for high-performance quasi solid-state (QSS) zinc-cobalt batteries (ZCBs) and zinc-air batteries (ZABs). Density functional theory (DFT) calculation reveals that the doping effect of Co2+ into O-VSe2 nanostructure could increase the density of states near the edge of the conduction band, demonstrating ultrafast electron transport kinetics. Most interestingly, the optimal O-Co0.33 V0.67 Se2 cathode-based QSS-ZCB exhibits an ultrahigh specific capacity of 422.7 mAh g-1 at a current density of 1 A g-1 , excellent energy density of 186.4 Wh kg-1 , tremendous power density of 5.65 kW kg-1 , and ultralong cycle life (86.9% capacity retention after 3000 cycles). Furthermore, O-Co0.33 V0.67 Se2 air-cathode based QSS-ZAB delivers a peak power density of 162 mW cm-2 and ultralong cycle life over 100 h. These experimental and theoretical studies indicate that the electrochemically induced, cobalt stabilizes the vanadium is essential to boost the energy storage properties and cycle life of both ZCBs and ZABs.

9.
J Endourol ; 34(4): 450-455, 2020 04.
Article in English | MEDLINE | ID: mdl-31973590

ABSTRACT

Purpose: Several case series have demonstrated the safety and feasibility of outpatient robot-assisted radical prostatectomy (RARP) in well-selected patients; however, the patient perspective of this practice has not been well explored. In this study, we explored patients' perspectives on the potential barriers and benefits of outpatient RARP. Materials and Methods: We developed a multidimensional questionnaire to assess socioeconomic status, presence of caretaker at home, preferred transportation to the emergency room in case of chest pain or postsurgical complications, readiness for discharge at postanesthesia care unit (PACU), and potential barriers for discharge. In addition, patients were asked to provide an estimate of overnight hospitalization costs and their willingness to pay out-of-pocket expenses for their overnight stay. Patients who underwent RARP between August 1, 2018, and April 30, 2019, were asked to fill the questionnaire within the first week following their operation. Results: During our study, 157/292 (53.8%) of men undergoing RARP from a single high-volume robotic surgeon completed the survey. Patients who completed <80% of the survey (n = 5) were excluded from the final analysis. Thirty-seven (24.3%) patients felt that they would have been ready for discharge immediately from PACU, and 48 (31.6%) patients after extended recovery and before midnight. Only 17.8% (n = 27) of the patients claim that they experienced a medical intervention in the hospital that could not have been managed at home. The main barriers for same-day discharge were pain (55.9%, 80/143), catheter discomfort (44.7%, 64/143), insufficient education about catheter care (31.4%, 45/143), postoperative nausea and vomiting (15.3%, 22/143), and medical complications (13.2%, 19/143). Conclusions: Two-thirds of patients following RARP did not feel ready to be discharged on the day of their surgery. Further research is necessary to identify patients who may benefit from this approach to reduce health care costs while minimizing patient postoperative morbidity.


Subject(s)
Prostatic Neoplasms , Robotic Surgical Procedures , Robotics , Humans , Male , Outpatients , Patient Discharge , Postoperative Complications , Prostatectomy , Prostatic Neoplasms/surgery , Treatment Outcome
10.
Front Surg ; 5: 58, 2018.
Article in English | MEDLINE | ID: mdl-30283787

ABSTRACT

Objectives: The purpose of this study was to investigate the impact of neoadjuvant chemotherapy (NAC) on perioperative morbidity and on oncological outcomes according to the type of chemotherapy regimen administered to patients with muscle-invasive bladder cancer (MIBC) who subsequently underwent radical cystectomy (RC). Methods: Data were collected retrospectively on 40 patients with bladder urothelial carcinoma who had at least two cycles of NAC, followed by RC, from 2011 to 2015 at our institution. The outcomes evaluated were NAC toxicity, perioperative complications, cancer-specific, and overall survival. Results: Among these cases, 23 patients (57.5%) received methotrexate, vinblastine, doxorubicin and cisplatin (MVAC), 4 patients (10%) received gemcitabine and cisplatin (GC), and 13 patients (32.5%) received other regimes. The early and late postoperative complication rates were 35% and 12.5%. Regarding toxicity, 85% of patients had at least one side effect of NAC, but only 21.7% discontinued therapy in the MVAC group. The pathological complete response (pCR) rates for cisplatin-based regimens (MVAC and GC) and other regimens were 44.4 and 15.4%, respectively, (p = 0.09). The pathological partial response (pPR) rates for cisplatin-based regimens and other regimens were 66.7 and 15.4%, respectively, (p = 0.002). Patients treated with a cisplatin-based chemotherapy regimen had longer overall survival than those treated with other regimen (median 38.1 vs. 18.4 months, p = 0.01). Conclusions: NAC administration was not associated with high toxicity or surgical morbidity. The pathological response rates and survival outcomes in the cisplatin-based regimens were higher than with those with non-cisplatin-based regimens. These data support the use, in patients elective to a neoadjuvant setting prior to RC for MBIC, of a cisplatin-based regimen.

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