Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 16 de 16
Filter
Add more filters










Publication year range
1.
World J Orthop ; 15(7): 642-649, 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39070933

ABSTRACT

BACKGROUND: Tibial avulsion fractures of the posterior cruciate ligament (PCL) are challenging to treat and compromise knee stability and function. Traditional open surgery often requires extensive soft tissue dissection, which may increase the risk of morbidity. In response to these concerns, arthroscopic techniques have been evolving. The aim of this study was to introduce a modified arthroscopic technique utilizing an M-shaped suture fixation method for the treatment of tibial avulsion fractures of the PCL and to evaluate its outcomes through a case series. AIM: To evaluate the effects of arthroscopic M-shaped suture fixation on treating tibia avulsion fractures of the PCL. METHODS: We developed a modified arthroscopic M-shaped suture fixation technique for tibia avulsion fractures of the PCL. This case series included 18 patients who underwent the procedure between January 2021 and December 2022. The patients were assessed for range of motion (ROM), Lysholm score and International knee documentation committee (IKDC) score. Postoperative complications were also recorded. RESULTS: The patients were followed for a mean of 13.83 ± 2.33 months. All patients showed radiographic union. At the final follow-up, all patients had full ROM and a negative posterior drawer test. The mean Lysholm score significantly improved from 45.28 ± 8.92 preoperatively to 91.83 ± 4.18 at the final follow-up (P < 0.001), and the mean IKDC score improved from 41.98 ± 6.06 preoperatively to 90.89 ± 5.32 at the final follow-up (P < 0.001). CONCLUSION: The modified arthroscopic M-shaped suture fixation technique is a reliable and effective treatment for tibia avulsion fractures of the PCL, with excellent fracture healing and functional recovery.

2.
Chemosphere ; 361: 142551, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38852280

ABSTRACT

The fate of volatile organic compounds (VOC) vapors in the unsaturated zone is the basis for evaluating the natural attenuation potential and vapor intrusion risk. Microcosm and column experiments were conducted to study the effects chemical speciation and soil types/properties on the fate of petroleum VOCs in unsaturated zone. The biodegradation and total attenuation rates of the seven VOCs obtained by microcosm experiments in black soil and yellow earth were also generally higher than those in floodplain soil, lateritic red earth, and quartz sand. The VOC vapors in floodplain soil, lateritic red earth, and quartz sand showed slow total attenuation rates (<0.3 d-1). N-pentane, methylcyclopentane, and methylcyclohexane showed lower biodegradation rates than octane and three monoaromatic hydrocarbons. Volatilization into the atmosphere and biodegradation are two important natural attenuation paths for VOCs in unsaturated soil columns. The volatilization loss fractions of different volatile hydrocarbons in all five unsaturated soils were generally in the order: n-pentane (93.5%-97.8%) > methylcyclopentane (77.2%-85.5%) > methylcyclohexane (53.5%-69.2%) > benzene (17.1%-73.3%) > toluene (0-45.7%) > octane (1.9%-34.2%) > m-xylene (0-5.7%). The fractions by volatilization into the atmosphere of all seven hydrocarbons in quartz sand, lateritic red earth, and floodplain soil were close and higher compared to the yellow earth and black soil. Overall, this study illustrated the important roles chemical speciation and soil properties in determining the vapor-phase transport and natural attenuation of VOCs in the unsaturated zone.


Subject(s)
Biodegradation, Environmental , Petroleum , Soil Pollutants , Soil , Volatile Organic Compounds , Volatile Organic Compounds/analysis , Volatile Organic Compounds/chemistry , Petroleum/analysis , Soil/chemistry , Soil Pollutants/analysis , Soil Pollutants/chemistry , Adsorption , Volatilization , Pentanes/chemistry , Pentanes/analysis , Octanes/chemistry , Toluene/chemistry , Toluene/analysis , Benzene/analysis , Benzene/chemistry
3.
Nano Lett ; 24(25): 7716-7723, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38848111

ABSTRACT

Mixed-dimensional heterostructures integrate materials of diverse dimensions with unique electronic functionalities, providing a new platform for research in electron transport and optoelectronic detection. Here, we report a novel covalently bonded one-dimensional/two-dimensional (1D/2D) homojunction structure with robust junction contacts, which exhibits wide-spectrum (from the visible to near-infrared regions), self-driven photodetection, and polarization-sensitive photodetection capabilities. Benefiting from the ultralow dark current at zero bias voltage, the on/off ratio and detectivity of the device reach 1.5 × 103 and 3.24 × 109 Jones, respectively. Furthermore, the pronounced anisotropy of the WSe2 1D/2D homojunction is attributed to its low symmetry, enabling polarization-sensitive detection. In the absence of any external bias voltage, the device exhibits strong linear dichroism for wavelengths of 638 and 808 nm, with anisotropy ratios of 2.06 and 1.96, respectively. These results indicate that such mixed-dimensional structures can serve as attractive building blocks for novel optoelectronic detectors.

4.
Environ Sci Technol ; 58(28): 12477-12487, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-38943037

ABSTRACT

Although the impacts of exotic wetland plant invasions on native biodiversity, landscape features, and carbon-nitrogen cycles are well appreciated, biogeochemical consequences posed by ecological competition, such as the heterogeneity of dissolved organic matter (DOM) from plant detritus and its impact on the formation of reactive oxygen species, are poorly understood. Thus, this study delves into O2•- photogeneration potential of DOM derived from three different parts (stem, leaf, and panicle) of invasive Spartina alterniflora (SA) and native Phragmites australis (PA). It is found that DOM from the leaves of SA and the panicles of PA has a superior ability to produce O2•-. With more stable aromatic structures and a higher proportion of sulfur-containing organic compounds, SA-derived DOM generally yields more O2•- than that derived from PA. UVA exposure enhances the leaching of diverse DOM molecules from plant detritus. Based on the reported monitoring data and our findings, the invasion of SA is estimated to approximately double the concentration of O2•- in the surrounding water bodies. This study can help to predict the underlying biogeochemical impacts from the perspective of aquatic photochemistry in future scenarios of plant invasion, seawater intrusion, wetland degradation, and elevated solar UV radiation.


Subject(s)
Wetlands , Superoxides/metabolism , Introduced Species , Plants/metabolism
5.
Sci Total Environ ; 927: 172333, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38608896

ABSTRACT

Although ligand-promoted photodissolution of ferrihydrite (FH) has long been known for low molecular weight organic acids (LMWOAs), such as oxalate (Oxa) and malonate (Mal), photochemistry of coprecipitated FH with Oxa and Mal remains unknown, despite the importance of these mineral-organic associations in carbon retention has been acknowledged recently. In this study, ferrihydrite-LMWOAs associations (FLAs) were synthesized under circumneutral conditions. Photo-dissolution kinetics of FLAs were compared with those of adsorbed LMWOAs on FH surface and dissolved Fe-LMWOAs complexes through monitoring Fe(II) formation and organic carbon decay. For aqueous Fe(III)-LMWOAs complexes, Fe(II) yield was controlled by the initial concentration of LMWOAs and nature of photochemically generated carbon-centered radicals. Inner-sphere mononuclear bidentate (MB) configuration dominated while LMWOAs were adsorbed on the FH surface. MB complex of FH-Oxa was more photoreactive, leading to the rapid depletion of Oxa. Oxa can be readsorbed but in the form of binuclear bidentate and outer-sphere complexation, with much lower photoreactivity. While LMWOAs was coprecipitated with FH, the combination mode of LMWOAs with FH includes surface adsorption with a mononuclear bidentate structure and internal physical inclusion. Higher content of LMWOAs in the FLAs promoted the photo-production of Fe(II) as compared to pure FH, while it was not the case for FLAs containing moderate amounts of LMWOAs. The distinct photochemistry of adsorbed and coprecipitated Fe-LMWOAs complexes is attributed to ligand availability and configuration patterns of LMWOAs on the surface or entrapped in the interior structure. The present findings have significant implications for understanding the photochemical redox cycling of iron across the interface of Fe-organic mineral associates.

6.
Water Res ; 255: 121519, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38552488

ABSTRACT

Whilst it is generally recognized that phosphate enables to promote the removal of some organic pollutants with peroxymonosulfate (PMS) oxidation, however, there is an ongoing debate as to whether free radicals are involved. By integrating different methodologies, here we provide new insights into the reaction mechanism of the binary mixture of phosphates (i.e., NaH2PO4, Na2HPO3, and NaH2PO2) with peroxymonosulfate (PMS) or hydrogen peroxide (H2O2). Enhanced degradation of organic pollutants and observation of 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) adducts (i.e. DMPOOH and 5,5-dimethyl-2-oxopyrroline-1-oxyl (DMPOX)) with electron paramagnetic resonance (EPR) in most phosphates/PMS system seemly support a radical-dominant mechanism. However, fluorescence probe experiments confirm that no significant amount of hydroxyl radicals (•OH) are produced in such reaction systems. PMS in the phosphate solutions (without any organics) remains relatively stable, but is only consumed while organic substrates are present, which is distinct from a typical radical-dominant Co2+/PMS system where PMS is continuously decomposed. Through density functional theory (DFT) calculation, the energy barriers of the phosphates/PMS reaction processes are greatly decreased when non-radical mechanism dominates. Complementary evidence suggests that the reactive intermediates of PMS-phosphate complex, rather than the free radicals, are capable of oxidizing electron-rich substrates such as DMPO and organic pollutants. Taking the case of phosphate/PMS system as an example, this study demonstrates the necessity of acquisition of lines of evidence for resolving paradoxes in identifying EPR adducts.

7.
Chemosphere ; 336: 139275, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37343641

ABSTRACT

Traditional natural attenuation studies focus on aqueous process in the saturated zone while vapor-phase biodegradation and natural attenuation in the unsaturated zone received much less attention. This study used microcosm experiments to explore the vapor-phase biodegradation and natural attenuation of 23 petroleum VOCs in the unsaturated zone including 7 monoaromatic hydrocarbons, 6 n-alkanes, 4 cycloalkanes, 3 alkylcycloalkanes and 3 fuel ethers. We found that monoaromatic hydrocarbon vapors were easily attenuated with significantly high first-order attenuation rates (9.48 d-1-43.20 d-1) in live yellow earth, of which toluene and benzene had the highest rates (43.20 d-1 and 28.32 d-1, respectively). The 13 aliphatic hydrocarbons and 3 fuel ethers all have relatively low attenuation rates (<0.54 d-1) in live soil and negligible biodegradation contribution. We explored the effects of soil types (black soil, yellow earth, lateritic red earth and quartz sand), soil moisture (2, 5, 10, and 17 wt%) contents and temperatures (4, 15, 25, 35 and 45 °C) on the vapor attenuation. Results showed that increasing soil organic matter (SOM) content, silt content, porosity and soil microorganism numbers enhanced contaminant attenuation and remediation efficiency. Increasing moisture content reduced the apparent first-order biodegradation rates of monoaromatic hydrocarbon vapors. The vapor-phase biodegradation had optimal temperature (∼25 °C in yellow earth) and increasing or decreasing temperature slowed down biodegradation rate. Overall, this study enhanced our understanding of vapor-phase biodegradation and natural attenuation of petroleum VOCs in the unsaturated zone, which is critical for the long-term management and remediation of petroleum contaminated site.


Subject(s)
Petroleum , Soil Pollutants , Petroleum/metabolism , Hydrocarbons/metabolism , Biodegradation, Environmental , Gases , Soil , Soil Pollutants/analysis , Ethers
8.
Natl Sci Rev ; 9(3): nwab050, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35401989

ABSTRACT

Room-temperature sodium-sulfur batteries (RT-Na-S batteries) are attractive for large-scale energy storage applications owing to their high storage capacity as well as the rich abundance and low cost of the materials. Unfortunately, their practical application is hampered by severe challenges, such as low conductivity of sulfur and its reduced products, volume expansion, polysulfide shuttling effect and Na dendrite formation, which can lead to rapid capacity fading. The review discusses the Na-S-energy-storage chemistry, highlighting its promise, key challenges and potential strategies for large-scale energy storage systems. Specifically, we review the electrochemical principles and the current technical challenges of RT-Na-S batteries, and discuss the strategies to address these obstacles. In particular, we give a comprehensive review of recent progresses in cathodes, anodes, electrolytes, separators and cell configurations, and provide a forward-looking perspective on strategies toward robust high-energy-density RT-Na-S batteries.

9.
Nanomicro Lett ; 14(1): 50, 2022 Jan 25.
Article in English | MEDLINE | ID: mdl-35076763

ABSTRACT

Silicon monoxide (SiO) is an attractive anode material for next-generation lithium-ion batteries for its ultra-high theoretical capacity of 2680 mAh g-1. The studies to date have been limited to electrodes with a relatively low mass loading (< 3.5 mg cm-2), which has seriously restricted the areal capacity and its potential in practical devices. Maximizing areal capacity with such high-capacity materials is critical for capitalizing their potential in practical technologies. Herein, we report a monolithic three-dimensional (3D) large-sheet holey graphene framework/SiO (LHGF/SiO) composite for high-mass-loading electrode. By specifically using large-sheet holey graphene building blocks, we construct LHGF with super-elasticity and exceptional mechanical robustness, which is essential for accommodating the large volume change of SiO and ensuring the structure integrity even at ultrahigh mass loading. Additionally, the 3D porous graphene network structure in LHGF ensures excellent electron and ion transport. By systematically tailoring microstructure design, we show the LHGF/SiO anode with a mass loading of 44 mg cm-2 delivers a high areal capacity of 35.4 mAh cm-2 at a current of 8.8 mA cm-2 and retains a capacity of 10.6 mAh cm-2 at 17.6 mA cm-2, greatly exceeding those of the state-of-the-art commercial or research devices. Furthermore, we show an LHGF/SiO anode with an ultra-high mass loading of 94 mg cm-2 delivers an unprecedented areal capacity up to 140.8 mAh cm-2. The achievement of such high areal capacities marks a critical step toward realizing the full potential of high-capacity alloy-type electrode materials in practical lithium-ion batteries.

10.
ACS Appl Mater Interfaces ; 13(42): 50005-50016, 2021 Oct 27.
Article in English | MEDLINE | ID: mdl-34637269

ABSTRACT

Practical applications of carbon anodes in high-power potassium-ion batteries (PIBs) were hampered by their limited rate properties, due to the sluggish K+ transport kinetics in the bulk. Constructing convenient ion/electron transfer channels in the electrode is of great importance to realize fast charge/discharge rates. Here, cross-linked porous carbon nanofibers (inner porous carbon nanotubes and outer soft carbon layer) modified with oxygen-containing functional groups were well designed as anodes to realize robust de-/potassiation kinetics. The novel anode delivered excellent rate capabilities (107 mAh g-1 at 20 A g-1 and 78 mAh g-1 at 40 A g-1) and superior cycling stability (76% capacity retention after 14,000 cycles at 2 A g-1). In situ XRD measurement, in situ Raman spectra, and galvanostatic intermittent titration verified its surface-dominated potassium storage behavior with fast de-/potassiation kinetics, excellent reversibility, and rapid ion/electron transport. Moreover, theoretical investigation revealed that the carboxyl groups in the carbon offered additional capacitive adsorption sites for K+, thus significantly enhancing the reversible capacity. Surprisingly, a full cell using the anode and perylene-3,4,9,10-tetracarboxylic dianhydride cathode achieved an outstanding power density of 23,750 W kg-1 and superior fast charge/slow discharge performance.

11.
ACS Appl Mater Interfaces ; 13(7): 8497-8506, 2021 Feb 24.
Article in English | MEDLINE | ID: mdl-33586950

ABSTRACT

Potassium-ion hybrid capacitors (KIHCs) have attracted growing attention due to the natural abundance and low cost of potassium. However, KIHCs are still limited by sluggish redox reaction kinetics in electrodes during the accommodation of large-sized K+. Herein, a starch-derived hierarchically porous nitrogen-doped carbon (SHPNC) anode and active carbon cathode were rationally designed for dual-carbon electrode-based KIHCs with high energy density. The hierarchical structure and rich doped nitrogen in the SHPNC anode result in a distensible interlayer space to buffer volume expansion during K+ insertion/extraction, offers more electrochemical active sites to achieve high specific capacity, and has highly efficient channels for fast ion/electron transports. The in situ Raman and ex situ TEM demonstrated a reversible electrochemical behavior of the SHPNC anode. Thus, the SHPNC anode delivers superior cycling stability and a high reversible capacity (310 mA h g-1 at 50 mA g-1). In particular, the KIHCs assembled by the SHPNC anode and commercial active carbon cathode can deliver a high energy density of 165 W h kg-1 at a current density of 50 mA g-1 and an ultra-long cycle life of 10,000 cycles at 1 A g-1 (calculated based on the total mass of the anode and cathode).

12.
Medicine (Baltimore) ; 99(24): e20558, 2020 Jun 12.
Article in English | MEDLINE | ID: mdl-32541479

ABSTRACT

BACKGROUND: Cervical cancer (CC) is a very common and malignant tumor in female population. Although a variety of single medications are reported to treat this condition, they all have limited efficacy. Previous studies have reported the combination of paclitaxel, carboplatin, and bevacizumab (PCB) can be used for the treatment of patients with CC effectively. However, no systematic review has explored its efficacy and safety. This study will address its efficacy and safety systematically and comprehensively. METHODS: The following electronic databases will be retrieved from their inceptions to the January 1, 2020 to identify all potential associated studies: MEDLINE, EMBASE, Cochrane Library, Scopus, Web of Science, CINAHL, Google scholar, and Chinese Biomedical Literature Database. We will include randomized controlled trials (RCTs) of adult women (≥18 years) with CC globally. Eligible interventions will target any forms of PCB. The study methodological quality of all included studies will be appraised using Cochrane risk of bias tool. Statistical analysis will be undertaken using RevMan 5.3 software. In addition, we will perform a narrative synthesis to describe quality and content of the evidence. RESULTS: This study will summarize recent evidence and provide quality evidence for the efficacy and safety of PCB on CC. CONCLUSION: The findings of this study will seek to identify the efficacy and safety of PCB and suggest future directions for research efforts targeting CC among this population. SYSTEMATIC REVIEW REGISTRATION: INPLASY202040195.


Subject(s)
Antineoplastic Agents/therapeutic use , Bevacizumab/therapeutic use , Carboplatin/therapeutic use , Paclitaxel/therapeutic use , Uterine Cervical Neoplasms/drug therapy , Antineoplastic Combined Chemotherapy Protocols , Female , Humans , Meta-Analysis as Topic , Systematic Reviews as Topic
13.
Nanomicro Lett ; 12(1): 113, 2020 May 22.
Article in English | MEDLINE | ID: mdl-34138147

ABSTRACT

Potassium-ion hybrid capacitors (KIHCs) have attracted increasing research interest because of the virtues of potassium-ion batteries and supercapacitors. The development of KIHCs is subject to the investigation of applicable K+ storage materials which are able to accommodate the relatively large size and high activity of potassium. Here, we report a cocoon silk chemistry strategy to synthesize a hierarchically porous nitrogen-doped carbon (SHPNC). The as-prepared SHPNC with high surface area and rich N-doping not only offers highly efficient channels for the fast transport of electrons and K ions during cycling, but also provides sufficient void space to relieve volume expansion of electrode and improves its stability. Therefore, KIHCs with SHPNC anode and activated carbon cathode afford high energy of 135 Wh kg-1 (calculated based on the total mass of anode and cathode), long lifespan, and ultrafast charge/slow discharge performance. This study defines that the KIHCs show great application prospect in the field of high-performance energy storage devices.

14.
Org Biomol Chem ; 14(42): 10070-10073, 2016 Oct 25.
Article in English | MEDLINE | ID: mdl-27722692

ABSTRACT

Hydrogen peroxide and anhydride mediated transformation of enamides to afford substituted α-acyloxy ketones is described. This transition-metal-free cascade reaction has a broad substrate scope and high efficiency. The acyl intramolecular migration procedure successfully achieved this acyloxylation process under mild conditions and increased the atom efficiency.

15.
Chem Asian J ; 11(20): 2829-2833, 2016 Oct 20.
Article in English | MEDLINE | ID: mdl-27582251

ABSTRACT

A novel and convenient one-pot route for the synthesis of 3-benzyl-2-phenylquinolin-4(1 H)-ones has been developed under transition-metal-free conditions. This new strategy features high yield and good functional group tolerance. In addition, a proposed mechanism has been confirmed for this reaction.

16.
J Org Chem ; 81(1): 25-31, 2016 Jan 04.
Article in English | MEDLINE | ID: mdl-26624930

ABSTRACT

A conversion of pyridines and enamides for the synthesis of 3-bromo-imidazo[1,2-a]pyridines was developed by copper-mediated aerobic oxidative coupling in a one-pot manner. This procedure tolerates various functional groups and affords a series of 3-bromo-imidazo[1,2-a]pyridines under mild conditions.

SELECTION OF CITATIONS
SEARCH DETAIL