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1.
Int J Biol Macromol ; : 134248, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39098463

RESUMO

Passive daytime radiative cooling is a zero-energy consumption cooling technology, which can dissipate heat to outer space via infrared radiation. Recently, coupling radiative cooling technology and thermoelectric devices to generate electricity has attracted much attention. However, existing radiative cooling integrated thermoelectric devices still suffer from low-temperature gradient and output voltage. Here, based on the Mie scattering and internal reflection enhancing principle, an impact-inducing geometry reconstruction approach was proposed to fabricate hierarchical nanostructured cellulosic coatings with good daytime cooling performance to achieve stable electricity generation function, which can be realized by using a scalable and facile wet ball milling technology. Guided by the theoretical simulations of the finite difference time domain method (FDTD), the cellulose and TiO2 nanoparticles can assemble into spherical envelope structured coatings drying by the shear, impact, and friction interaction in the ball milling process, dramatically enhancing the Mie scattering and internal reflection of coatings. The cellulosic coatings exhibit sunlight reflectivity of 0.962 and infrared emissivity of 0.94, resulting in a daytime radiative cooling efficiency of 5.9 °C under direct sunlight. Energy Plus stimulation demonstrated 35 % cooling energy and 468.9 kWh of cooling energy can be saved annually in China. Meanwhile, this cellulosic coating-based thermoelectric device can deliver a high voltage output of 150 mV under 1 Sun due to the strong bonding and high-temperature gradient formation (30 °C), which is higher than previous reports. This study will facilitate the development of sustainable power generation device for the goal of green future.

2.
Nano Lett ; 24(31): 9477-9486, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39072447

RESUMO

Capacitive deionization (CDI), renowned for its eco-friendly and low-energy approach to water treatment, encounters challenges in achieving optimal deionization efficiency and cycle stability despite recent advancements. In this study, the CDI electrodes were crafted with multilevel pore structures using modified cellulose (MCNF) and porous activated MXene (PAMX), aiming to the impact of surface modification on adsorption efficiency, stability, and overall performance. The experimental results demonstrated the superiority of the electrode, specifically the formulation integrating sulfonic acid-treated cellulose and PAMX (SCNF@PAMX). This configuration exhibited remarkably a higher desalination rate (3.91 mg·g-1·min-1) and enhanced desalination capacity (31.24 mg·g-1), with cycling performance exceeding 90%. Density functional theory calculations underscored the formidable adsorption energy of SCNF for Na+ (2.15 eV), surpassing that of other modified electrodes. The enhancement of deionization performance and efficiency through surface charge modification, altering Na+ electrostatic adsorption, lays a solid foundation for advancing more efficient and durable seawater desalination technologies.

3.
Int J Biol Macromol ; 267(Pt 2): 131653, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631568

RESUMO

Aerogel possesses the advantages of high specific surface area, low density, and high porosity, which have shown great application in thermal regulation due to its efficient light scattering capability. However, traditional polymer-based aerogels have poor mechanical properties and lack ductility in outdoor applications, the cooling efficiency of the material is easily affected by damage during transportation, installation, and environmental factors. In this work, combining the porous nature of aerogels and the high ductility of membranes, a polylactic acid-based porous membrane cooler was developed by combining a regular honeycomb surface porous structure design and physical/chemical modification to enhance flexibility, using a simple non-solvent induced phase separation method. This porous membrane exhibits both super-flexibility (116 % elongation at break) and porous characteristics. It achieves a sub-ambient temperature decrease of 4-6 °C under direct sunlight. The optimized porous membrane demonstrates high solar reflectance (94 % of peak reflectivity, 90 % of average reflectivity) and strong infrared emissivity (96 % of peak emissivity, 91 % of average emissivity), it also maintains a solar peak reflectivity of 91 % under 100 % tensile strain and 1000 bending cycles, the cooler still maintains a cooling effect of 2-5 °C below ambient temperature. This work paves the way for developing mechanical flexible and strong radiative coolers for thermal regulation.


Assuntos
Membranas Artificiais , Poliésteres , Poliésteres/química , Porosidade , Polimerização , Temperatura , Resistência à Tração
4.
ACS Nano ; 18(5): 4376-4387, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38270109

RESUMO

Harvesting atmospheric water and converting it into electricity play vital roles in advancing next-generation energy conversion systems. However, the current water harvester systems suffer from a weak water capture ability and poor recyclability due to high diffusion barriers and low sorption kinetics, which significantly limit their practical application. Herein, we drew inspiration from the natural "Pump effect" observed in wood and successfully developed a dual "absorption-adsorption" networked MXene aerogel atmospheric water harvester (MAWH) through ice templating and confining LiCl processes, thereby serving multiple purposes of clean water production, passive dehumidification, and power generation. The MAWH benefits from the dual H-bond network of MXene and cellulose nanocrystals (absorption network) and the hygroscopic properties of lithium chloride (adsorption network). Furthermore, its aligned wood-like channel structure efficiently eliminates water nucleation near the 3D network, resulting in fast moisture absorption. The developed MAWH demonstrates a high moisture absorption ability of 3.12 g g-1 at 90% relative humidity (RH), featuring rapid vapor transport rates and durable cyclic performance. When compared with commercial desiccants such as the 4A molecular sieve and silica gel, the MAWH can reduce the RH from 80% to 20% within just 6 h. Most notably, our integrated MAWH-based water harvesting-power generation system achieves a high voltage of ∼0.12 V at 77% RH, showcasing its potential for practical application. These developed MAWHs are considered as high-performance atmospheric water harvesters in the water collection and power generation field.

5.
Small ; 19(28): e2300076, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37029708

RESUMO

Polysulfides huttling and interfacial instability of Lithium-anode are the main technical issues hindering commercialization of high-energy-density lithium-sulfur batteries. Simply addressing the problem of polysulfide shuttling or lithium dendrite growth can result in safety hazards or short lifespan. To synchronously tackle the aforementioned issues, the authors have designed an asymmetric cellulose gel electrolyte, a defective and ionized UiO66/black phosphorus heterostructure coating layer (Di-UiO66/BP) and a cationic cellulose gelelectrolyte (QACA). Defective and ionized engineered UiO66 particles significantly enhances performance of UiO66/BP layer in anchoring free polysulfides, promoting smooth and effective polysulfide conversion and expediting the redox kinetics of sulfur cathode, therefore suppressing polysulfide shuttling. QACA electrolyte with numerous cationic groups can interact with anions via electrostatic adsorption, thus enhancing lithium-ion transference number and contributing to formation of stable solid electrolyte interface to suppress lithium dendrite growth. Owing to the superior performance of QACA/Di-UiO66/BP, the final cells exhibit outstanding electrochemical performance, presenting high sulfur utilization (1420.1 mAh g-1 at 0.1 C), high-rate capacity (665.4 mAh g-1 at 4 C) and long cycle lifespan. This work proposes a strategy of designing asymmetric electrolytes to simultaneously address the challenges in both S-cathode and Li-anode, which contributes to advanced Li-S batteries and their practical application.

6.
Ann Surg Oncol ; 18(6): 1575-81, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21431408

RESUMO

BACKGROUND: This randomized phase III study was to evaluate the efficacy and safety of cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) for the treatment of peritoneal carcinomatosis (PC) from gastric cancer. METHODS: Sixty-eight gastric PC patients were randomized into CRS alone (n = 34) or CRS + HIPEC (n = 34) receiving cisplatin 120 mg and mitomycin C 30 mg each in 6000 ml of normal saline at 43 ± 0.5°C for 60-90 min. The primary end point was overall survival, and the secondary end points were safety profiles. RESULTS: Major clinicopathological characteristics were balanced between the 2 groups. The PC index was 2-36 (median 15) in the CRS + HIPEC and 3-23 (median 15) in the CRS groups (P = 0.489). The completeness of CRS score (CC 0-1) was 58.8% (20 of 34) in the CRS and 58.8% (20 of 34) in the CRS + HIPEC groups (P = 1.000). At a median follow-up of 32 months (7.5-83.5 months), death occurred in 33 of 34 (97.1%) cases in the CRS group and 29 of 34 (85.3%) cases of the CRS + HIPEC group. The median survival was 6.5 months (95% confidence interval 4.8-8.2 months) in CRS and 11.0 months (95% confidence interval 10.0-11.9 months) in the CRS + HIPEC groups (P = 0.046). Four patients (11.7%) in the CRS group and 5 (14.7%) patients in the CRS + HIPEC group developed serious adverse events (P = 0.839). Multivariate analysis found CRS + HIPEC, synchronous PC, CC 0-1, systemic chemotherapy ≥ 6 cycles, and no serious adverse events were independent predictors for better survival. CONCLUSIONS: For synchronous gastric PC, CRS + HIPEC with mitomycin C 30 mg and cisplatin 120 mg may improve survival with acceptable morbidity.


Assuntos
Adenocarcinoma Mucinoso/mortalidade , Adenocarcinoma/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células em Anel de Sinete/mortalidade , Carcinoma de Células Escamosas/mortalidade , Hipertermia Induzida , Neoplasias Peritoneais/mortalidade , Neoplasias Gástricas/mortalidade , Adenocarcinoma/secundário , Adenocarcinoma/terapia , Adenocarcinoma Mucinoso/secundário , Adenocarcinoma Mucinoso/terapia , Adulto , Idoso , Carcinoma de Células em Anel de Sinete/secundário , Carcinoma de Células em Anel de Sinete/terapia , Carcinoma de Células Escamosas/secundário , Carcinoma de Células Escamosas/terapia , Quimioterapia Adjuvante , Quimioterapia do Câncer por Perfusão Regional , Cisplatino/administração & dosagem , Terapia Combinada , Feminino , Humanos , Injeções Intraperitoneais , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Estadiamento de Neoplasias , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/terapia , Estudos Prospectivos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapia , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
7.
Hepatogastroenterology ; 57(99-100): 663-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20698246

RESUMO

BACKGROUND/AIMS: Gastric cancer (GC) is the leading cause of death in China. Although surgery based comprehensive treatment is the best approach to improve survival, postoperative recurrence is a major problem. This study was aimed to find out the relationship of cancer recurrence with major clinico-pathological factors, with special attention focused on time of recurrence. METHODOLOGY: Data of 59 recurrences after surgery among 286 GC patients were systemically collected and analyzed. Time of recurrence, the relationship between clinical stages and time of recurrence, and between number of adjuvant chemotherapy cycles and time of recurrence were evaluated. RESULTS: 76.3% (45/59) recurrence happened within 1 year after surgery. Median time to recurrence was 7 months. Most recurrences were locoregional recurrence (57.6%). The differences in time of recurrence among stage I, stage II, stage III and stage IV were statistically not significant (p > 0.05, Kruskal-Wallis Test). There were significant differences among different adjuvant chemotherapy cycles for time to recurrence (p = 0.014, Kruskal-Wallis Test). CONCLUSION: Close monitoring and active followup of patients with GC should be conducted over the first 2 years after operation. Adjuvant chemotherapy could prolong recurrence-free survival.


Assuntos
Recidiva Local de Neoplasia/epidemiologia , Neoplasias Gástricas/patologia , Adulto , Idoso , Quimioterapia Adjuvante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Estudos Retrospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Fatores de Tempo
8.
World J Gastroenterol ; 11(8): 1105-8, 2005 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-15754389

RESUMO

AIM: To clarify the clinicopathologic significance of COX-2 expression in human colorectal cancer. METHODS: A total of 128 surgically resected colorectal cancer specimens were immunohistochemically analyzed with the use of anti-COX-2, anti-VEGF and anti-MMP-2 antibodies. The relationship between the cyclooxygenase-2 expression in primary lesions of colorectal cancer and clinicopathologic parameters was evaluated by chi-square test. RESULTS: Among 128 cases of colorectal cancer, 87 (67.9%) were positive for cyclooxygenase-2. The expression of cyclooxygenase-2 was significantly correlated with the depth of invasion, stage of disease, and metastasis (lymph node and liver). Patients in T3-T4, stages III-IV and with metastasis had much higher expression of cyclooxygenase-2 than ones in T1-T2, stages I-II and without metastasis (P<0.05). Among 45 cases of colorectal cancer with lymph node metastasis, the COX-2- positive rate was 86.7% (39/45) for primary lesions and diffuse cytoplasmic staining for COX-2 protein was detected in cancer cells in 100% of metastatic lesions of the lymph nodes. VEGF expression was detected in 49 tumors (38.3%), and VEGF expression was closely correlated with COX-2 expression. The positive expression rate of VEGF (81.6%) in the cyclooxygenase-2-positive group was higher than that in the cyclooxygenase-2- negative group (18.4%, P<0.05). MMP-2 expression was detected in 88 tumors (68.8%), and MMP-2 expression was closely correlated with COX-2 expression. The positive expression rate of MMP-2 (79.6%) in the positive COX-2 group was higher than that in the negative COX-2 group (20.4%, P<0.05). CONCLUSION: Cyclooxygenase-2 may be associated with tumor progression by modulating the angiogenesis and cancer cell motility and invasive potential in colorectal cancer and it can be used as a possible biomarker.


Assuntos
Biomarcadores Tumorais , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/secundário , Prostaglandina-Endoperóxido Sintases/metabolismo , Adulto , Idoso , Ciclo-Oxigenase 2 , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Proteínas de Membrana , Pessoa de Meia-Idade , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Ai Zheng ; 23(9): 1069-73, 2004 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-15363204

RESUMO

BACKGROUND & OBJECTIVE: It remains controversial whether lymph node micrometastasis has impact on staging and prognosis of colorectal cancer. This study was to compare the sensitivity of reverse transcriptase- polymerase chain reaction (RT-PCR) in detecting lymph node micrometastasis of colorectal cancer with pathological morphology and immunohistochemistry, and assess the impact of lymph node micrometastasis on clinical staging and prognosis of colorectal cancer. METHODS: Lymph nodes from 56 cases of colorectal cancer radical resection specimens were studied by RT-PCR to detect the expression of cytokeratin 20 (CK20) mRNA, and compared with routine pathology detection using hematoxylin and eosine (HE) staining, and immunohistochemistry using monoclonal antibody specifically against CK20. The patients had been followed up for 5 years. RESULTS: A total of 432 lymph nodes in 56 patients were analysed by pathological morphology, immunohistochemistry, and RT-PCR, the detected positive lymph node numbers were 247 (57.2%), 269 (62.3%), and 316 (73.1%), respectively. The difference in metastatic lymph node numbers was significant between pathological morphology and RT-PCR method (P< 0.05). Five-year disease- free survival rates of PN0,PN1, and PN2 stages detected by RT-PCR method were 100%, 61.9%, and 55.6%, respectively, significantly higher than those obtained by pathological morphology method, which were 80.0%, 60.0%, and 50.0%, respectively (P< 0.05). CONCLUSIONS: Detecting lymph node micrometastasis of colorectal cancer with RT-PCR method is more sensitive than pathological morphology. RT-PCR method could define the TNM stage and make accurate prognosis for patients with colorectal cancer.


Assuntos
Carcinoma Ductal/metabolismo , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas de Filamentos Intermediários/biossíntese , Linfonodos/patologia , Adulto , Idoso , Carcinoma Ductal/secundário , Carcinoma de Células em Anel de Sinete/metabolismo , Carcinoma de Células em Anel de Sinete/secundário , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Proteínas de Filamentos Intermediários/genética , Queratina-20 , Linfonodos/metabolismo , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
World J Gastroenterol ; 9(6): 1237-40, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12800231

RESUMO

AIM: Cyclooxygenase-2 is involved in a variety of important cellular functions, including cell growth and differentiation, cancer cell motility and invasion, angiogenesis and immune function. However, the role of cyclooxygenase-2 as an angiogenic factor in colorectal cancer tissue is still unclear. We investigated the relationship between cyclooxygenase-2 and angiogenesis by analyzing the expression of cyclooxygenase-2 in colorectal cancer tissue, as well as its association with vascular endothelial growth factor (VEGF) and microvascular density (MVD). METHODS: The expression of cyclooxygenase-2, VEGF, as well as MVD was detected in 128 cases of colorectal cancer by immunohistochemical staining. The relationship between the cyclooxygenase-2 and VEGF expression and MVD was evaluated. Our objective was to determine the effect of cyclooxygenase-2 on the angiogenesis of colorectal cancer tissue. RESULTS: Among 128 cases of colorectal cancer, 87 were positive for cyclooxygenase-2 (67.9 %), and 49 for VEGF (38.3 %), respectively. The microvessel counts ranged from 23 to 142, with a mean of 51.7 (standard deviation, 19.8). The expression of cyclooxygenase-2 was correlated significantly with the depth of invasion, stage of disease, metastasis (lymph node and liver), VEGF expression and MVD. Patients in T3-T4, stage III-IV and with metastasis had much higher expression of cyclooxygenase-2 than patients in T1-T2, stage I-II and without metastasis (P<0.05). The positive expression rate of VEGF (81.6 %) in the cyclooxygenase-2 positive group was higher than that in the cyclooxygenase-2 negative group (18.4 %, P<0.05). Also, the microvessel count (56+/-16) in cyclooxygenase-2 positive group was significantly higher than that in cyclooxygenase-2 negative group (43+/-12, P<0.05). The microvessel count in tumors with positive cyclooxygenase-2 and VEGF was the highest (60+/-18, 41-142, P<0.05), whereas that in tumors with negative cyclooxygenase-2 and VEGF was the lowest (39+/-16, 23-68, P<0.05). CONCLUSION: Cyclooxygenase-2 may be associated with tumor progression by madulating the angiogenesis in colorectal cancer tissue and used as a possible biomarker.


Assuntos
Adenocarcinoma/irrigação sanguínea , Adenocarcinoma/metabolismo , Neoplasias Colorretais/irrigação sanguínea , Neoplasias Colorretais/metabolismo , Isoenzimas/metabolismo , Neovascularização Patológica/fisiopatologia , Prostaglandina-Endoperóxido Sintases/metabolismo , Adulto , Idoso , Vasos Sanguíneos/patologia , Ciclo-Oxigenase 2 , Fatores de Crescimento Endotelial/metabolismo , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Linfocinas/metabolismo , Masculino , Proteínas de Membrana , Microcirculação , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
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