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1.
Toxics ; 12(8)2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39195703

RESUMO

The airport and its surrounding areas are home to a variety of pollution sources, and air pollution is a recognized health concern for local populated regions. Submicron particulate matter (PM1 with an aerodynamic diameter of <1 mm) is a typical pollutant at airports, and the enrichment of heavy metals (HMs) in PM1 poses a great threat to human health. To comprehensively assess the source-specific health effects of PM1-bound HMs in an airport community, PM1 filter samples were collected around the Tianjin Binhai International Airport for 12 h during the daytime and nighttime, both in the spring and summer, and 10 selected HMs (V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, and Pb) were analyzed. The indicatory elements of aircraft emissions were certified as Zn and Pb, which accounted for more than 60% of the sum concentration of detected HMs. The health risks assessment showed that the total non-cancer risks (TNCRs) of PM1-bound HMs were 0.28 in the spring and 0.23 in the summer, which are lower than the safety level determined by the USEPA, and the total cancer risk (TCR) was 2.37 × 10-5 in the spring and 2.42 × 10-5 in the summer, implying that there were non-negligible cancer risks in the Tianjin Airport Community. After source apportionment with EF values and PMF model, four factors have been determined in both seasons. Consequently, the source-specific health risks were also evaluated by combining the PMF model with the health risk assessment model. For non-cancer risk, industrial sources containing high concentrations of Mn were the top contributors in both spring (50.4%) and summer (44.2%), while coal combustion with high loads of As and Cd posed the highest cancer risk in both seasons. From the perspective of health risk management, targeted management and control strategies should be adopted for industrial emissions and coal combustion in the Tianjin Airport Community.

2.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(6): 742-747, 2024 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-38918197

RESUMO

Objective: To evaluate the influence of lateral hinge fracture (LHF) on the early effectiveness of supramalleolar osteotomy (SMO) and to explore the related risk factors for LHF. Methods: A total of 39 patients (39 feet) with varus-type ankle osteoarthritis treated with SMO between January 2016 and December 2022 were analyzed retrospectively. There were 10 males and 29 females, aged from 41 to 71 years (mean, 57.7 years). According to Takakura stage, there were 6 feet in stage Ⅱ, 19 feet in stage Ⅲa, and 14 feet in stage Ⅲb. The LHF was recognized by the immediate postoperative X-ray film. The osteotomy healing time and the changes of pain visual analogue scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS) score, tibial anterior surface angle (TAS), tibial lateral surface angle (TLS), and tibiotalar angle (TT) before and after operation were compared between patients with and without LHF. The age, gender, affected side, body mass index, Takakura stage, preoperative VAS score, preoperative AOFAS score, preoperative TAS, preoperative TLS, preoperative TT, SMO correction angle, osteotomy distraction, distance from medial osteotomy to ankle joint line (MD), and distance from lateral osteotomy to ankle joint line (LD) were compared between with and without LHF patients, and further logistic regression analysis was used to screen the risk factors of LHF during SMO. Results: All patients were followed up 12-54 months (mean, 27.1 months). During operation, 13 feet developed LHF (group A) and 26 feet did not develop LHF (group B). X-ray film reexamination showed that 1 patient in group A complicated with tibial articular surface cleft fracture had delayed osteotomy and healed successfully after plaster fixation; the osteotomy of other patients healed, and there was no significant difference in healing time between the two groups ( P>0.05). At last follow-up, there were significant differences in VAS score, AOFAS score, TAS, TLS, and TT of the two groups when compared with preoperative ones ( P<0.05), but there was no significant difference in the changes of above indicators before and after operation between the two groups ( P>0.05). The differences in SMO correction angle, osteotomy distraction, and LD between with and without LHF patients were significant ( P<0.05), and further logistic regression analysis showed that excessive LD was the risk factor of LHF during SMO ( P<0.05). Conclusion: Too high or too low lateral hinge position during SMO may lead to LHF, but as long as appropriate treatment and rehabilitation measurements are taken, the early effectiveness is similar to that of patients without LHF.


Assuntos
Articulação do Tornozelo , Osteotomia , Humanos , Osteotomia/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto , Articulação do Tornozelo/cirurgia , Idoso , Resultado do Tratamento , Osteoartrite/cirurgia , Osteoartrite/etiologia , Amplitude de Movimento Articular , Tíbia/cirurgia , Fraturas do Tornozelo/cirurgia
3.
Nano Lett ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842083

RESUMO

The primary challenge for resonant-gravimetric gas sensors is the synchronous improvement of the sensitivity and response time, which is restricted by low adsorption capacity and slow mass transfer in the sensing process and remains a great challenge. In this study, a novel 2D/2D Cu-TCPP@ZnIn2S4 composite is successfully constructed, in which Cu-TCPP MOF is used as a core substrate for the growth of 2D ultrathin ZnIn2S4 nanosheets with well-defined {0001} crystalline facets. The Cu-TCPP@ZnIn2S4 sensor exhibited high sensitivity (1.5 Hz@50 and 2.3 Hz@100 ppb), limit of detection (LOD: 50 ppb), and ultrafast (9 s @500 ppb) detection of triethylamine (TEA), which is the lowest LOD and the fastest sensor among the reported TEA sensors at room temperature, tackling the bottleneck for the ultrafast detection of the resonant-gravimetric sensor. These above results provide an innovative and easily achievable pathway for the synthesis of heterogeneous structure sensing materials.

4.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(3): 309-314, 2024 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-38500424

RESUMO

Objective: To compare the effectiveness of talonavicular-cuneiform joint fusion with iliac bone grafting and without bone grafting in the treatment of Müller-Weiss diseases (MWD). Methods: The clinical data of 44 patients (44 feet) with MWD who received talonavicular-cuneiform joint fusion between January 2017 and November 2022 and met the selection criteria was retrospectively analyzed. Among them, 25 patients were treated with structural iliac bone grafting (bone grafting group) and 19 patients without bone grafting (non-bone grafting group). There was no significant difference ( P>0.05) in age, gender composition, body mass index, disease duration, affected side, Maceira stage, and preoperative American Orthopaedic Foot and Ankle Society (AOFAS) score, visual analogue scale (VAS) score, anteroposterior/lateral Meary angle, and Pitch angle between the two groups. Operation time, operation cost, and postoperative complications were recorded in the two groups. AOFAS and VAS scores were used to evaluate the function and pain degree of the affected foot. Meary angle and Pitch angle were measured on the X-ray film, and the joint fusion was observed after operation. The difference (change value) of the above indexes before and after operation was calculated for comparison between groups to evaluate the difference in effectiveness. Results: The operation was successfully completed in both groups, and the incisions in the two groups healed by first intention. The operation time and cost in the bone grafting group were significantly more than those in the non-bone grafting group ( P<0.05). All patients were followed up. The median follow-up time was 41.0 months (range, 16-77 months) in the non-bone grafting group and 40.0 months (range, 16-80 months) in the bone grafting group. There was skin numbness of the medial dorsalis of the foot in 1 case, internal fixation stimulation in 2 cases, and pain at the iliac bone harvesting area in 1 case of the bone grafting group. There was skin numbness of the medial dorsalis of the foot in 1 case and muscle atrophy of the lower limb in 1 case of the non-bone grafting group. There was no significant difference in the incidence of complications between the two groups ( P>0.05). At last follow-up, the AOFAS scores of the two groups significantly improved when compared with those before operation, while the VAS scores significantly decreased, the anteroposterior/lateral Meary angle and Pitch angle significantly improved, and the differences were significant ( P<0.05). There was no significant difference in the change values of outcome indicators between the two groups ( P>0.05). There was no delayed bone union or bone nonunion in both groups, and joint fusion was achieved at last follow-up. Conclusion: In the treatment of MWD, there is no significant difference in effectiveness and imaging improvement of talonavicular-cuneiform joint fusion combined with or without bone grafting. However, non-bone grafting can shorten the operation time, reduce the cost, and may avoid the complications of bone donor site.


Assuntos
Doenças Ósseas , Doenças do Pé , Humanos , Transplante Ósseo , Doenças do Pé/cirurgia , Hipestesia , Dor , Estudos Retrospectivos , Resultado do Tratamento , Masculino , Feminino
5.
Arch Orthop Trauma Surg ; 144(1): 161-170, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37789151

RESUMO

PURPOSE: The purpose of this study was to investigate the changes in clinical outcomes and alignment of the ipsilateral knee and ankle in patients with varus ankle osteoarthritis after supramalleolar osteotomy (SMO). METHODS: We retrospectively reviewed 23 patients (24 ankles) with Takakura II, IIIa and IIIb ankle osteoarthritis treated with SMO between May 2017 and March 2022. The radiologic parameters of ankles contained medial distal tibial angle (TAS), tibiotalar angle (TT), tibial lateral surface (TLS), tibial plafond inclination (TPI) and talar inclination (TI). The radiologic parameters of knees contained medial proximal tibial angle (MPTA), joint line convergence angle (JLCA), the knee joint line orientation relative to ground (G-KJLO) and WBL. Hip-knee-ankle angle (HKA) was also collected. The Takakura system was used for evaluating the ankle osteoarthritis and the Kellgren-Lawrence (KL) system was used for evaluating the knee osteoarthritis. Clinical evaluation of the ankle joints contained American Orthopedic Foot and Ankle Society (AOFAS), range of motion (ROM) and visual analogue scale (VAS). Clinical evaluation of the knee joints contained Japanese Orthopaedic Association Scores (JOA), ROM, VAS. RESULTS: The mean follow-up times were 20.3 ± 7.3 months (range 12-38). According to the radiologic evaluation, the TAS increased from preoperative 84.7° ± 2.0° to 91.2° ± 1.8° at the last follow-up (P < 0.001). The TPI and TI decreased from 4.4° ± 4.2° and 11.0° ± 5.2° to 0.1° ± 4.7° and 4.1° ± 4.8° (P < 0.001 for both). The TT angel improved from 9.5° ± 4.1° to 4.9° ± 3.3° (P < 0.001). No significant differences were found regarding MPTA, JLCA, G-KJLO, knee WBL and HKA (P > 0.05 for all). The Takakura stage improved after SMO (P < 0.001) whilst the KL stage maintains the similar lever (P > 0.05). According to the clinical evaluation, the AOFAS significantly increased from 67.5 ± 10.6 to 88.5 ± 9.3 and the VAS of the ankle decreased from 4.7 ± 1.6 to 1.2 ± 1.1, whilst there were no changes on VAS and even the JOA and knee ROM after SMO (P > 0.05 for all). CONCLUSIONS: SMO can alleviate the symptoms of varus ankle osteoarthritis and delay the time for ankle replacement or arthrodesis by redistributing the abnormal stress of the ankle and restoring the congruence of the tibiotalar joint. In addition, it did not induce the clinical symptoms of knee without compromising lower limb alignment or knee joint line orientation in the short term. LEVEL OF EVIDENCE: Level IV case series.


Assuntos
Tornozelo , Osteoartrite do Joelho , Humanos , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Seguimentos , Estudos Retrospectivos , Extremidade Inferior , Articulação do Joelho/cirurgia , Osteotomia , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia
6.
Target Oncol ; 18(6): 869-883, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37847485

RESUMO

BACKGROUND: Poly (ADP-ribose) polymerase (PARP) inhibitors are a new maintenance therapy option for patients with ovarian cancer (OC). OBJECTIVE: To evaluate the efficacy and influencing factors of the novel PARP inhibitor niraparib for maintenance treatment of Chinese patients with advanced OC. PATIENTS AND METHODS: In this retrospective multicenter real-world study patients with advanced OC from 15 hospitals throughout China were enrolled. The primary endpoint was progression-free survival (PFS) and the secondary endpoints included the time to treatment discontinuation and safety. Least Absolute Shrinkage and Selection Operator (LASSO) regression was used to identify possible risk factors for PFS, after which a prediction model was established to evaluate the likelihood of achieving an 18-month PFS. The relationship between the dose of niraparib and PFS was also evaluated. RESULTS: The PFS rates of 199 patients at 6, 12, 18, 24, and 30 months were 87.4%, 75.9%, 63.6%, 56.1%, and 51.8%, respectively. LASSO regression model revealed that only age < 65 years (P = 0.011), BRCA mutations (P < 0.001), and R0 status after cytoreductive surgery (P = 0.01) were significant factors associated with prolonged PFS times. Based on the LASSO logistic regression analysis, a clinical prediction formula was developed: - 2.412 + 1.396Age≥65yr + 2.374BRCAwt + 1.387R1 + 0.793Interval≥12w + 0.178BMI>24kg/m2 which yielded a cut-off value of 0.091, an area under the curve (AUC) of 0.839 (0.763-0.916), a sensitivity of 94.3%, and an accuracy of 78.5%. A nomogram was then built to visualize the results. The major treatment-emergent adverse events of ≥ grade 3 included a platelet count decrease (19.1%), white blood cell count decrease (15.1%), neutrophil count decrease (13.1%), and anemia (18.6%). The 18-month PFS rates in patients treated with 200 mg niraparib were somewhat higher than in patients treated with 100 mg after 3-months of therapy. CONCLUSIONS: For Chinese OC patients, niraparib, particularly at a 200 mg individual starting dose, was an effective therapy with easily manageable safety.


Maintenance therapy with poly (ADP-ribose) polymerase inhibitors is a new option for patients with ovarian cancer (OC) after they have received platinum-based chemotherapy to reduce the recurrence or relapse rates, but it remains unclear whether there are any changes in efficacy and safety when different starting doses of niraparib are administrated to Chinese patients, who typically have a bodyweight < 77 kg. We found that niraparib exhibited satisfactory efficacy with tolerable safety during maintenance therapy for advanced OC whether administered at 100 mg or 200 mg doses. We believe these regimens can serve as a valuable addition to the previous results of randomized controlled trials.


Assuntos
Neoplasias Ovarianas , Humanos , Feminino , Idoso , Carcinoma Epitelial do Ovário/tratamento farmacológico , Indazóis/farmacologia , Indazóis/uso terapêutico , Piperidinas/farmacologia , Piperidinas/uso terapêutico
7.
Sci Total Environ ; 905: 167247, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37739079

RESUMO

The effects of antibiotics on the proliferation of antibiotic resistant genes (ARGs) in WWTPs have drawn great attention in recent years. The effects of antibiotics on ARGs in the enhanced biological phosphorus removal (EBPR) system and its mechanisms, however, are still not well understood. In this study, EBPR systems were constructed using activated sludge to investigate the effects of ten commonly detected antibiotics in the environment on the proliferation of ARGs and the mechanisms involved. The results showed that the total abundance of ARGs increased to varying degrees with the addition of different antibiotics (0.05 mmol/L), and the top 30 ARGs increased by 271.1 % to 370.0 %. Mobile genetic elements (MGEs), functional modules, and the bacteria community were consistently related to the changes in ARGs. Refractory antibiotics, in particular, have a stronger promoting effect on transduction in the EBPR system. The insertion sequence common region (ISCR) and transposon (Tnp) were identified as crucial factors in the proliferation of ARGs. Moreover, the risk of polyphosphate accumulating organisms (PAOs) carrying ARGs in the presence of antibiotics should not be ignored. Our findings emphasize the potential efficacy of employing strategies that target the reduction of MGEs, regulation of cellular communication, and management of microbial communities to effectively mitigate the risks associated with ARGs.


Assuntos
Antibacterianos , Genes Bacterianos , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Bactérias/genética , Esgotos/microbiologia
8.
Anal Chem ; 94(51): 18050-18058, 2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36507709

RESUMO

The development of formaldehyde (HCHO) gas sensors with high sensitivity, good selectivity, and fast response at room temperature is an important research topic. The resonant microcantilever, with high sensitivity, easy batch manufacturing, and integration, generates sensing signals based on the relationship between the frequency and the mass addition of the adsorbed molecules and shows good application potential in HCHO detection. Herein, we report two species of MoS2 nanosheets (NSs) with 1T and 2H phases as sensitive materials to construct high-performance HCHO resonant cantilever sensors. The 2H-MoS2 gas sensors show better sensitivity toward HCHO compared to the 1T-MoS2 gas sensor. Specifically, the 2H-MoS2 sensor displayed a high sensitivity (Hz) of 13.6-1 ppm HCHO at room temperature, with high selectivity, low limit of detection (10 ppb), and good humidity resistance. The effect of phase structures on the sensing performance was studied by in situ characterizations, thermodynamic analysis, and density functional theory calculations. The good sensing ability could be attributed to the abundant active sites induced by the surface defects, suitable adsorption strength, and the outstanding thermodynamic performance of the 2H-MoS2. The combination of two-dimensional (2D) nanosheet and microcantilever sensors provides a new direction for developing a high-performance room-temperature gas sensor in the future.

9.
Nanoscale Adv ; 4(4): 1227-1234, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36131768

RESUMO

The work aims to elucidate the importance of hybrid microwave annealing technology (HMA) in ultrafast fabrication of deficient cadmium stannate (Cd2SnO4) photoanodes with a worm-like porous structure and significant enhancement of solar water oxidation performance and stability. Comparison of three synthetic routes and experimental characterization revealed that relative to conventional thermal annealing (CTA) or even with extra HMA for 5 min (optimal), direct HMA for only 8 min can form cubic Cd2SnO4 thin films of unique worm-like and highly porous nanostrucures with a large interfacial surface area, high degree of phase crystallinity and high-concentration defects. The obtained results from the photoluminescence spectra and the charge efficiency measurements collaboratively verified that compared to using CTA treatment solely, the HMA treatment is effective in significantly improving charge separation, recombination and transfer processes, mainly by an over 13.5-fold increase in the bulk charge separation efficiency. Benefiting from these merits, under optimized conditions the HMA treated Cd2SnO4 film exhibited a remarkable 6-fold and 2-fold solar photocurrent enhancement compared with those of the CTA treated one and the combined CTA-HMA treated one, respectively, and an IPCE of 39% at 300 nm and 18% at 350 nm at 1.7 V versus RHE. Despite a high external bias required in this case, the study provides a simple route for synthesis of ideal Cd2SnO4 photoanodes which can be further extended to doping engineering and non-noble metal cocatalyst deposition.

10.
ACS Appl Mater Interfaces ; 14(32): 37059-37067, 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35938577

RESUMO

Highly conductive corrosion protection coatings are necessary for metallic bipolar plates (BPs) of the proton-exchange membrane fuel cell. Graphene coatings have the potential of protecting metal substrates from corrosion without obscuring their excellent electrical conductivity. The electron transfer in the coatings facilitates the formation of galvanic cells, so the challenge is to block the mass transfer of the corrosion process. Here, we constructed highly compacted hybrid coatings with aligned water-dispersible graphene layers. The water-dispersible graphene (SG) held an electrical conductivity of >270 S cm-1 while providing an unprecedented dispersibility, which can be redispersed from filter cake with a concentration of 120 mg mL-1 or even dry state. The cohesion of the hybrid coatings was attributed to the interaction between highly aligned SG layers and the heterointerface between SG and polydopamine (PDA), as proven by the molecular dynamics simulations. The hybrid coatings presented a corrosion current density of 0.023 µA cm-2 and an interfacial contact resistance of 9.94 mΩ cm2, which meets the requirements of corrosion protection and electron transfer for the coatings on metallic BPs. The water-based fabrication method of the graphene-dominated hybrid coatings was a promising alternative of the vacuum-based deposition method for industrial production.

11.
J Colloid Interface Sci ; 608(Pt 1): 1074-1085, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34785455

RESUMO

Two-dimensional (2D) ZnSnO3 is a promising candidate for future gas sensors due to its high chemical response and excellent electronic properties. However, the preparation of 2D ZnSnO3 nanosheets by utilizing soluble inorganic salts and nonorganic solvents remains a challenge. In this work, 2D ZnSnO3 was synthesized via a facile graphene oxide (GO)-assisted co-precipitation method, in which inorganic salts in the aqueous phase replaced metal organic salts in a non-aqueous system. Meanwhile, a "dissolution and recrystallization" mechanism was proposed to explain the transformation from 3D nanocubes to 2D nanosheets. In comparison, the 2D ZnSnO3 nanosheets showed a higher response to formaldehyde (HCHO) at low operating temperature (100 °C). The response (Ra/Rg) of the 2D ZnSnO3 sensor to 10 ppm HCHO was as high as 57, which was approximately 5 times the response of the ZnSnO3 nanocubes sensor. However, the ZnSnO3 nanocubes sensor showed better gas sensing performance to ethanol at high temperature (200 °C). Different gas-sensitive properties were attributed to the different gas diffusion and adsorption processes caused by the morphology and nanostructure. Moreover, both sensors could detect either 0.1 ppm HCHO or ethanol at their optimum operating temperature. This work presents a relatively economical method to prepare 2D compound metal oxides, provides a novel "dissolution and recrystallization" mechanism for 2D multi-metal oxide preparation, and sheds light on the great potential of high-efficiency HCHO and/or ethanol gas sensors.


Assuntos
Nanoestruturas , Formaldeído , Metais , Óxidos , Temperatura
12.
Sci Total Environ ; 744: 140977, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-32755786

RESUMO

Water reclamation and ecological reuse is gradually becoming a popular solution to address the high pollutant loads and insufficient ecological flow of many urban rivers. However, emerging contaminants in water reuse system and associated human health and ecological risks need to be assessed. This study determined the occurrence and human health and ecological risk assessments of 35 emerging contaminants during one year, including 5 types of persistent organic pollutants (POPs), 5 pharmaceutical and personal care products (PPCPs), 7 endocrine disrupting chemicals (EDCs) and 18 disinfection by-products (DBPs), in a wastewater treatment plant (WWTP) and receiving rivers, as well as an unimpacted river for comparison. Results showed that most of PPCPs and EDCs, especially antibiotics, triclosan, estrogens and bisphenol A, occurred frequently at relatively high concentrations, and they were removed from 20.5% to 88.7% with a mean of 58.9% via WWTP. The highest potential noncarcinogenic and carcinogenic risks in different reuse scenarios were assessed using maximal detected concentrations, all below the acceptable risk limits, with the highest total combined risk value of 9.21 × 10-9 and 9.98 × 10-7, respectively. Ecological risk assessment was conducted using risk quotient (RQ) method and indicated that several PPCPs, EDCs and haloacetonitriles (HANs) pose high risk (RQ > 1) to aquatic ecology in the rivers, with the highest RQ up to 83.8. The study suggested that ecological risks need to be urgently addressed by updating and optimizing the process in WWTPs to strengthen the removal efficiencies of emerging contaminants. The study can serve as a reference for safer water reuse in the future, while further studies could be conducted on the health risk of specific groups of people, exposure parameters in water reuse, as well as more emerging contaminants.

13.
ACS Appl Mater Interfaces ; 11(48): 45214-45225, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31710803

RESUMO

In this work, three-dimensional (3D) hierarchical In2O3@SnO2 core-shell nanofiber (In2O3@SnO2) was designed and successfully prepared via a facile electrospinning and further hydrothermal methods. Vertically aligned SnO2 nanosheets uniformly grown on the outside surface of In2O3 nanofibers were clearly observed by field emission scanning electron microscopy. Besides, hierarchical core-shell nanostructure of In2O3@SnO2 was characterized by elemental maps using scanning transmission electron microscopy. The formaldehyde (HCHO) sensing performances of pure In2O3 nanofibers, SnO2 nanosheets, and In2O3@SnO2 core-shell nanocomposite were compared, and the In2O3@SnO2 nanocomposite possessed highest response value, fast response/recovery speed, best selectivity, and lowest HCHO detection limit. Specifically, the response value (Ra/Rg) of the In2O3@SnO2 nanocomposite reached 180.1 toward 100 ppm of HCHO gas, which was near 9 and 6 times higher than that of the pure In2O3 nanofibers (Ra/Rg = 19.7) and pure SnO2 nanosheets (Ra/Rg = 33.2), respectively. In addition, the gas sensor showed instantaneous response/recovery time (3/3.6 s) toward 100 ppm of HCHO at the optimal operation temperature of 120 °C. More importantly, the detection limit toward HCHO gas was as low as 10 ppb (Ra/Rg = 1.9), which could be used for trace HCHO gas detection. The excellent sensing properties of the In2O3@SnO2 were attributed to the synergistic effect of large specific surface areas of SnO2 nanosheet arrays, abundant adsorbed oxygen species on the surface, unique electron transformation between core-shell heterogeneous materials, and long electronic transmission channel of SnO2 transition layer. This work provides an efficient route for the preparation of novel hierarchical sensitive materials.

14.
Artigo em Chinês | MEDLINE | ID: mdl-21991807

RESUMO

OBJECTIVE: To investigate the method of combining radial forearm free flap and adjacent tissue flap in reconstruction of palatomaxillary defects and its effectiveness. METHODS: Between March 2005 and May 2010, 17 patients with palatomaxillary defects were treated. There were 11 males and 6 females with an age range of 45-74 years (mean, 62.5 years), including 1 case of benign tumor and 16 cases of malignant tumors (7 cases of squamous cell carcinoma of palate, 1 case of recurring squamous cell carcinoma of palate, 1 case of malignant melanoma of palate, 1 case of adenoid cystic carcinoma of palate, 1 case of malignant melanoma of maxilla, 1 case of ductal carcinoma of maxilla, and 4 cases of squamous cell carcinoma of maxilla). The maxillectomy defect ranged from 7.0 cm x 5.5 cm to 10.0 cm x 7.5 cm. According to Brown's classification for the maxillectomy defect, there were type II in 15 cases, type III in 2 cases. Palatomaxillary defects were repaired with radial forearm free flap and buccal fat pad in 11 cases, and with radial forearm free flap, buccal fat pad, and mandibular osteomuscular flap pedicled with temporal muscle in 6 cases. The effectiveness was evaluated after operation by observing the vitality of the flap, the functions of speech, swallowing, breath, and the facial appearance. RESULTS: All cases were followed up 6-12 months without tumor recurrence. All flaps and skin grafts at donor sites survived. The functions of speech, swallowing, and breath were normal without obvious opening limitation. The facial appearance was satisfactory without obvious maxillofacial deformity. No enophthalmos occurred in patients with orbital floor and infraorbital rim defects. The patients had no oronasal fistula with satisfactory oral and nasal functions. CONCLUSION: According to the type of palatomaxillary defects, it can have good early effectiveness to select combining radial forearm free flap and buccal fat pad or combining radial forearm free flap, buccal fat pad, and mandibular osteomuscular flap for repairing defects.


Assuntos
Neoplasias Maxilares/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Transplantes , Idoso , Feminino , Antebraço/cirurgia , Humanos , Masculino , Maxila/lesões , Pessoa de Meia-Idade , Palato/lesões , Transplante de Pele , Retalhos Cirúrgicos , Resultado do Tratamento
15.
J Hazard Mater ; 190(1-3): 214-21, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21458159

RESUMO

The long-term destabilization process of a water-in-oil emulsion was investigated with two different biodemulsifiers produced under different culture conditions by Alcaligenes sp. S-XJ-1. Biodemulsifier I was obtained by using paraffin as substrate at initial culture pH of 10 and biodemulsifier II was produced with waste frying oils at pH of 7. The former exhibited higher demulsifying ability and interfacial activity than the latter. Bottle test, microscopy and Turbiscan Lab(®) Expert were used to investigate the biological demulsification process. It was found that biodemulsifiers' ability to decrease the interfacial tension played a more important role in demulsification than their ability to decrease the surface tension. Owing to their amphiphilic nature, demulsification process began with the adsorption of the biodemulsifiers onto the water-oil interface. Then the biodemulsifiers reacted with the emulsifiers because of their interfacial activity. As a result, thin liquid film was removed from the surface of dispersed droplets and coalescence occurred. This led to the settling of the dispersed droplets and the clarification of the continuous phase. Turbiscan Lab(®) Expert can be used to evaluate the demulsification efficiency and to analyze the destabilization process of different biodemulsifiers. It is a rapid and accurate method to screen high-efficiency demulsifiers from other bioproducts.


Assuntos
Emulsificantes/farmacologia , Emulsões/química , Alcaligenes/química , Emulsificantes/química , Concentração de Íons de Hidrogênio , Óleos , Parafina , Tensão Superficial , Água
16.
J Hazard Mater ; 183(1-3): 466-73, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20702035

RESUMO

A biodemulsifier-producing strain of Alcaligenes sp. S-XJ-1, isolated from petroleum-contaminated soil of the Karamay Oilfield, exhibited excellent demulsifying ability. The application of this biodemulsifier significantly improved the quality of separated water compared with the chemical demulsifier, polyether, which clearly indicates that it has potential applications in the crude oil extraction industry. To optimize its biosynthesis, the impacts of carbon sources, nitrogen sources and pH were studied in detail. Paraffin, a hydrophobic carbon source, favored the synthesis of this cell wall associated biodemulsifier. The nitrogen source ammonium citrate stimulated the production and demulsifying performance of the biodemulsifier. An alkaline environment (pH 9.5) of the initial culture medium favored the strain's growth and improved its demulsifying ability. The results showed paraffin, ammonium citrate and pH had significant effects on the production of the biodemulsifier. These three variables were further investigated using a response surface methodology based on a central composite design to optimize the biodemulsifier yield. The optimal yield conditions were found at a paraffin concentration of 4.01%, an ammonium citrate concentration of 8.08 g/L and a pH of 9.35. Under optimal conditions, the biodemulsifier yield from Alcaligenes sp. S-XJ-1 was increased to 3.42 g/L.


Assuntos
Alcaligenes/metabolismo , Biodegradação Ambiental , Emulsões/metabolismo , Petróleo/metabolismo , Alcaligenes/crescimento & desenvolvimento , Tensoativos
17.
Bioresour Technol ; 100(24): 6481-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19643603

RESUMO

In order to lower the production cost, waste frying oils were used in the biosynthesis of demulsifier by Dietzia sp. S-JS-1, which was isolated from petroleum contaminated soil. After 7 days of cultivation, the biomass concentration of the most suitable waste frying oil (WFO II) culture reached 3.78 g/L, which was 2.4 times the concentration of paraffin culture. The biodemulsifier produced with WFO II culture broke the emulsions more efficiently than that produced with paraffin culture, given the same volume ratio of carbon source in the culture medium and the same cultivation conditions. It achieved 88.3% of oil separation ratio in W/O emulsion and 76.4% of water separation ratio in O/W emulsion within 5 h. With the aid of thin layer chromatography (TLC) and Fourier transform infrared (FTIR) spectrometry, biodemulsifiers produced from both paraffin and WFO II were identified as a mixture of lipopeptide homologues. The subtle variation in the distribution of these homologues and high biomass concentration of WFO II cultures may account for the afore-mentioned good demulsification performance.


Assuntos
Carbono/química , Corynebacterium/metabolismo , Emulsificantes/síntese química , Óleos/química , Parafina/química , Resíduos/análise , Biomassa , Corynebacterium/isolamento & purificação , Emulsões , Ácidos Graxos/metabolismo , Fermentação , Suspensões
18.
J Hazard Mater ; 169(1-3): 309-17, 2009 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-19443107

RESUMO

To reclaim treated steel wastewater as cooling water, manganese ore constructed wetland was proposed in this study for the removal of iron and manganese. In lab-scale wetlands, the performance of manganese ore wetland was found to be more stable and excellent than that of conventional gravel constructed wetland. The iron and manganese concentration in the former was below 0.05 mg/L at hydraulic retention time of 2-5 days when their influent concentrations were in the range of 0.16-2.24 mg/L and 0.11-2.23 mg/L, respectively. Moreover, its removals for COD, turbidity, ammonia nitrogen and total phosphorus were 55%, 90%, 67% and 93%, respectively, superior to the corresponding removals in the gravel wetland (31%, 86%, 58% and 78%, respectively). The good performance of manganese ore was ascribed to the enhanced biological manganese removal with the aid of manganese oxide surface and the smaller size of the medium. The presence of biological manganese oxidation was proven by the facts of good manganese removal in wetlands at chemical unfavorable conditions (such as ORP and pH) and the isolation of manganese oxidizing strains from the wetlands. Similar iron and manganese removal was later observed in a pilot-scale gravel-manganese-ore constructed wetland, even though the manganese ore portion in total volume was reduced from 100% (in the lab-scale) to only 4% (in the pilot-scale) for the sake of cost-saving. The quality of the polished wastewater not only satisfied the requirement for cooling water but also suitable as make-up water for other purposes.


Assuntos
Conservação dos Recursos Naturais , Metais Pesados/isolamento & purificação , Aço , Purificação da Água/métodos , Áreas Alagadas , Resíduos Industriais/prevenção & controle , Ferro/isolamento & purificação , Manganês/isolamento & purificação , Projetos Piloto
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