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Nanocomposites containing Ni or Co or NiCo alloy and nitrogen-doped carbon with diverse ratios have been prepared and utilized as active elements in supercapacitors. The atomic contents of nitrogen, nickel, and cobalt have been adjusted by the supplement amount of Ni and Co salts. In virtue of the excellent surface groups and rich redox active sites, the NC/NiCo active materials exhibit superior electrochemical charge-storage performances. Among these as-prepared active electrode materials, the NC/NiCo1/1 electrode performs better than other bimetallic/carbon electrodes and pristine metal/carbon electrodes. Several characterization methods, kinetic analyses, and nitrogen-supplement strategies determine the specific reason for this phenomenon. As a result, the better performance can be ascribed to a combination of factors including the high surface area and nitrogen content, proper Co/Ni ratio, and relatively low average pore size. The NC/NiCo electrode delivers a maximum capacity of 300.5 C g-1 and superior capacity retention of 92.30% after 3000 unceasing charge-discharge cycles. After assembling it into the battery-supercapacitor hybrid device, a high energy density of 26.6 Wh kg-1 (at 412 W kg-1 ) is achieved, comparable to the recent reports. Furthermore, this device can also power four light-emitting-diode (LED) demos, suggesting the potential practicability of these N-doped carbon compositing with bimetallic materials.
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Lithium-Sulfur batteries (LSBs) have been considered as a promising candidate for the next generation of energy storage systems due to their high theoretical capacity. However, there are still lots of pending scientific and technological issues to be solved. Framework materials show great potential to address the above-mentioned issues due to the highly ordered distribution of pore sizes, effective catalytic activity, and periodically arranged aperture. In addition, good tunability gives framework materials unlimited possibilities to achieve satisfying performance for LSBs. In this review, the recent advances in pristine framework materials, their derivatives, and composites have been summarized. And a short conclusion and outlook regard to future prospects for guiding the development of framework materials and LSBs.
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Fontes de Energia Elétrica , Lítio , EnxofreRESUMO
A novel method, reduction followed by oxidation procedure, has been developed to fabricate efficient electrodes derived from metal-organic frameworks (MOFs), which were synthesized using terephthalic acid (TP) and 1,3,5-benzenetricarboxylic acid (BTC) as organic ligands. The copper-based composites, namely Cu/CuxO@C (x = 1 and 2), were obtained through two steps: first calcining the precursors at high temperature under a nitrogen atmosphere, and then calcining in air to increase the number of porous active sites. For a more convenient description, the calcined materials are denoted as 800-TP, 900-TP, 800-BTC and 900-BTC, respectively, according to the calcination temperature and the corresponding organic ligand. Their electrochemical performances in supercapacitors (SCs) suggest that a higher calcination temperature endows the as-resultant materials with a larger specific surface area, higher carbon content, higher electrical conductivity, and better ion transport ability. For example, the 900-BTC electrode delivers a specific capacity of 400 C g-1 at a current density of 3 A g-1 under a three-electrode configuration. Even under a double-electrode system, the corresponding 900-BTC//AC device (AC represents activated carbon) also achieves superior electrochemical performance with an energy density of 24.02 W h kg-1 at a power density of 825 W kg-1 and the specific capacitance retention rate for the device is maintained at 91.7% after 3000 unceasing loops, indicating its potential for practical applications.
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OBJECTIVE: To study the clinical value of accelerated rehabilitation nursing (ARN) in improving the symptoms of PCa patients after surgery. METHODS: This study included 80 cases of PCa treated surgically in our hospital from October 2020 to October 2021. We randomly divided the patients into two groups of an equal number to receive ARN and routine nursing care (the control group), respectively. We obtained the scores of the patients on IPSS, TCM syndromes, quality of life (QOL) and pain, incidence of postoperative complications, satisfaction with nursing care and Gleason scores, and compared them between the two groups. RESULTS: The IPSS and TCM syndrome scores were significantly lower (P < 0.05 ), and the physical and psychological function score remarkably higher in the ARN than in the control group (P < 0.05), but there was no statistically significant difference in the social function scores between the two groups (P > 0.05). The postoperative pain score was also significantly lower in the ARN than in the control group (P < 0.05), and so was the incidence rate of postoperative complications (10% vs 37.5%, P < 0.05). The patients' satisfaction with nursing care was markedly higher in the former than in the latter group (90% vs 80%, P < 0.05). No statistically significant difference was observed in the Gleason scores between the two groups of patients. CONCLUSION: Accelerated rehabilitation nursing can effectively improve the symptoms of PCa patients after surgery and therefore deserves clinical application.
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Neoplasias da Próstata , Enfermagem em Reabilitação , Humanos , Masculino , Dor Pós-Operatória , Complicações Pós-Operatórias , Neoplasias da Próstata/cirurgia , Qualidade de Vida , SíndromeRESUMO
The electrocatalytic characteristics of nanostructures are significantly affected by surface structure. The strict regulation of structural characteristics is highly beneficial for the creation of novel nanocatalysts with enhanced electrocatalytic performance. This work reports a nitrite electrochemical sensor based on novel flower-like Pd-ZnO nanostructures. The Pd-ZnO nanocatalysts were synthesized through a simple hydrothermal method, and their morphology and structure were characterized via field-emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). Their electrocatalytical performance in the nitrite oxidation reaction was studied via cyclic voltammetry (CV) and the amperometric technique. Compared to pure ZnO and Pd nanoparticles, the Pd-ZnO nanostructures exhibited enhanced electrochemical performance in the nitrite oxidation reaction. In order to investigate the relationships between the structures of Pd-ZnO nanocatalysts and the corresponding electrocatalytic performances, different surface morphologies of Pd-ZnO nanocatalysts were fabricated by altering the solution pH. It was found that the flower-like Pd-ZnO nanostructures possessed larger effective surface areas and faster electron transfer rates, resulting in the highest electrocatalytic performance in the nitrite oxidation reaction. The designed nitrite sensor based on flower-like Pd-ZnO displayed a wide concentration linear range of 1 µM-2350 µM, a low detection limit of 0.2 µM (S/N of 3), and high sensitivity of 151.9 µA mM-1 cm-2. Furthermore, the proposed sensor exhibited perfect selectivity, excellent reproducibility, and long-time stability, as well as good performance in real sample detection.
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Nitritos , Óxido de Zinco , Óxido de Zinco/química , Reprodutibilidade dos Testes , Eletrodos , Limite de DetecçãoRESUMO
Transition metal hydroxides are a kind of promising electrode material in electrochemical energy storage, but the poor conductivity limits their application. Lanthanides are good proton conductors and can usually improve the intrinsic conductivity of other materials. By integrating the merits of lanthanide elements and transition metal hydroxide, we designed lanthanum oxide nickel hydroxide composites (LONH) with unique ultrathin triangle nanosheet morphology via a controllable synthetic strategy for high-performance supercapacitors. When the LONH is used as positive electrode material in aqueous asymmetric supercapacitor, it reveals an energy density (107.8 W h kg-1 at 800 W kg-1), rate performance (86.9% retention at 4 kW kg-1) and outstanding cycle stability (more than 90% retention after 3,000 cycles). This work confirms that compositing La2O3 and Ni(OH)2 can significantly improve the supercapacitor performance of both pristine La2O3 and transition metal hydroxide composites. We hope this work would offer a good prospect for developing other lanthanide-transition metal hydroxide composites as an attractive class of electrode materials in electrochemical energy storage.
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Electrocatalysis of the hydrogen evolution reaction (HER) is a vital and demanding, yet challenging, task to produce clean energy applications. Here, the RuRh2 bimetallene nanoring with rich structural defects is designed and successfully synthesized by a mixed-solvent strategy, displaying ascendant HER performance with high mass activity at -0.05 and -0.07 V, separately higher than that of the commercial Pt catalyst. Also, it maintains steady hydrogen bubble evolution even after 30 000 potential cycles in acid media. Furthermore, the RuRh2 bimetallene nanoring shows an outstanding activity in both alkaline and neutral media, outperforming that of Pt catalysts and other reported HER catalysts. A combination of atomic-scale structure observation and density functional theory calculations demonstrates that both the grain boundaries and symmetry breaking of RuRh2 bimetallene cannot only weaken the adsorption strength of atomic hydrogen, but also facilitate the transfer of electrons and the adsorption of reactants, further boosting the HER electrocatalytic performance in all pH values.
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Background: The efficacy and safety of corticosteroids and immunosuppressive therapy remain controversial for the treatment of immunoglobulin A nephropathy (IgAN). This study aimed to evaluate the effects of corticosteroid and immunosuppressant therapy in Chinese patients with early-stage IgAN whose estimated glomerular filtration rate (eGFR) was ≥45 ml/min/1.73 m2 and proteinuria was ≥1 g/24 h at biopsy. Methods: Patients with biopsy-proven IgAN were retrospectively enrolled from four study centers between 2007 and 2016. Patients were regularly followed up for at least 1 year or until the study end point. Patients were categorized into three treatment groups: supportive care (SC), steroids alone (CS), and steroids plus immunosuppressants (IT). The observed responses to therapy included complete remission (CR), partial remission (PR), no response (NR), and end-stage renal disease (ESRD). The primary end point of the current study was defined as a 50% decline in eGFR and/or ESRD. Results: A total of 715 patients (male 47% and female 53%) were recruited and followed up for 44.69 ± 24.13 months. The observed CR rate was 81.8% with corticosteroids alone (CS), 62.7% with corticosteroids + immunosuppresants (IT), and 37% with supportive care alone (SC). Renal outcomes were remarkably better in the CS group compared with the SC and IT groups (the percentage of patients reaching the end point in each group was 4.6 vs. 14.4 vs. 11.5%, respectively; p = 0.001). Moreover, 36 and 80-month renal survival were significantly better for the CS group (98.3 and 86.4%) than for the IT (94.2 and 82.4%) and SC (94.0 and 51.6%) groups. Early CKD stage also presented with better kidney survival (p < 0.001). Renal survival of CKD stage 1 patients was relatively good regardless of the specific treatment regimen. CS and IT treatment significantly improved renal survival for CKD stage 2 patients when compared with the SC group (p < 0.001 and 0.007, respectively). However, renal survival of CKD stage 3a patients was not impacted by any of the three treatment regimens. Subgroup analysis also showed that renal survival of patients with proteinuria >3.5 g, M1, E0, S1, T0, and C0 was significantly better in the CS group than in the SC and IT groups. A multivariate model showed that hypertension, serum creatinine, E1 lesion, and T1/T2 lesion remained independent predictors of poor renal survival. Conclusions: Immunosuppressive therapy does not have further benefit beyond that provided by steroids. Corticosteroids plus optimal supportive care may further be beneficial in treating early-stage IgAN patients in that it could significantly improve the short-term renal outcome.
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BACKGROUND: We aimed to evaluate the effect of immunosuppressant therapy for immunoglobulin A nephropathy (IgAN) patients with mild proteinuria (<1âg/d). METHODS: We recruited patients with biopsy-proven IgAN from 4 study centers. Patients were followed for more than 1 year or up to the study end point. Clinical indexes, renal pathological data, and treatment information were collected during the follow-up period. IgAN patients with mild proteinuria (<1âg/d at biopsy) were included. Patients were divided into a supportive care group (SC) and an immunosuppressant group (IT). Patients in the SC group received the optimal dose of renin angiotensin system inhibitors (RASi). Patients in the IT group received corticosteroids or immunosuppressant therapy plus RASi. Responses to therapy included complete remission (CR), partial remission (PR), no response (NR), and end stage renal disease (ESRD). A 50% decline in estimated glomerular filtration rate (eGFR) and/or ESRD was the primary end point of this study. RESULTS: 295 patients (36.3% male and 63.7% female) were included in this study and were followed for 49.46â±â24.35 months. We found a significant difference in estimated glomerular filtration rate, urine protein, mesangial hypercellularity, segmental glomerulosclerosis, cellular or fibrocellular crescents, and glomerulosclerosis between the 2 treatment groups at baseline. At the final follow-up, 224 patients (75.9%) achieved CR, 7 patients (2.4%) achieved PR, 55 patients (18.6%) had NR, and 9 patients (3.1%) reached ESRD. However, no significant differences were observed between the SC and IT groups with respect to CR (76.4% vs 73.5%, Pâ=â.659), PR (2.0% vs 4.1%, Pâ=â.329), NR (18.3% vs 20.4%, Pâ=â.728), and ESRD (3.3% vs 2.0%, Pâ=â1.000). Kidney survival rates were also comparable between the SC and IT groups (93.7% vs 94.1%, Pâ=â.808). We observed similar results after subgroup analysis according to chronic kidney disease stages or pathological manifestations. A multivariate model showed that segmental sclerosis (HR 9.55, 95% CI 1.04-88.16, Pâ=â.047) and glomerulosclerosis (HR 21.09, 95% CI 1.39-320.53, Pâ=â.028) were independent predictors of poor renal survival. CONCLUSIONS: Corticosteroids or immunosuppressants were not superior to supportive care in IgA nephropathy patients with mild proteinuria.
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Corticosteroides/uso terapêutico , Glomerulonefrite por IGA/tratamento farmacológico , Imunossupressores/uso terapêutico , Proteinúria/tratamento farmacológico , Adulto , Feminino , Glomerulonefrite por IGA/complicações , Humanos , Falência Renal Crônica/imunologia , Masculino , Adulto JovemRESUMO
Defect engineering is widely applied in transition metal dichalcogenides to produce high-purity hydrogen. However, the instability of vacancy states on catalysis still remains a considerable challenge. Here, our first-principles calculations showed that, by optimizing the asymmetric S vacancy in the highly asymmetric 1T' crystal of layered bitransition metal dichalcogenides (Co-MoS2) in light of Pd modulation, the relative amount of metastable phase and the quantity of active sites in the structure can be reduced and increased, respectively, leading to a further boosted hydrogen evolution reaction (HER) activity toward layered bi-transition metal dichalcogenides. Thus, we then used a "click" chemistry strategy to make such a catalyst with engineered unsaturated sulfur edges via a strong coupling effect between ultrafine Pd ensembles and Co-MoS2 nanosheets. As expected, the Pd-modulated Co-MoS2 nanosheets exhibited a very low overpotential of 60 mV at 10 mA cm-2 with a small Tafel slope (56 mV dec-1) for the HER in 1.0 M PBS, comparable to those of commercial Pt/C. In addition, their high HER activity was retained in acidic and alkaline conditions. Both the theoretical and experimental results revealed that Pd ensembles can efficiently activate and stabilize the inert basal plane S sites during HER processes as a result of the formation of Pd-S in Co-MoS2. This work not only provides a deeper understanding of the correlation between defect sites and intrinsic HER catalytic properties for transition metal chalcogenide (TMD)-based catalysts, but also offers new insights into better designing earth-abundant HER catalysts displaying high efficiency and durability.
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Low-cost and highly effective catalysts are crucial to the electrocatalytic hydrogen evolution reaction (HER). Among non-noble catalysts, molybdenum carbides are promising candidates because of their high reserves, stability, low cost, and structural diversity. In this work, we report a simple method to fabricate a hollow porous Mo2C@C nanoball through a hydrothermal preparation process of molybdenum precursors at high temperatures. Specifically, we have combined interfacial polymerization and the chelation effect to synthesize the Mo-polydopamine (Mo-PDA) precursor. As a result, Mo2C@C-3 only requires an ultralow Tafel slope (~55 mV dec-1) and low overpotential (η50 ≈ 167 mV) in a 0.5 M H2SO4 solution with long-term cycling stability. Besides, it also exhibits outstanding activity and stability under extensive HER testing in alkaline media. This study is promising for the development of advanced molybdenum carbide electrocatalysts toward electrochemical applications.
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Small molecules solely consisting of H, N, O, and S are highly relevant intermediates in atmospheric chemistry and biology. Even though several isomers of [HNO2S] have been computationally predicted, only the IR spectra for the two lowest-energy isomers HNSO2 and syn-syn HONSO have been previously reported. Herein, the photochemistry (193 nm laser) of HNSO2 in N2-, Ne-, and Ar-matrices (≤15 K) has been studied. Aside from syn-syn HONSO, several new isomers including anti-syn HONSO, gauche-syn HOSNO, syn HOS(O)N, anti HOS(O)N, syn HS(O)NO, anti HN(O)SO, gauche-syn HSONO, and an elusive caged-radical pair HOSËËNO have been identified. Additionally, the formation of fragments HONO, HOË, ËNO, and ËNO2 has also been observed. The characterization of these species with matrix-isolation IR and UV/Vis spectroscopy is supported by 15N-labeling and quantum chemical computations at the B3LYP/6-311++G(3df,3pd) level. Furthermore, the photo-induced isomerization reactions, including the conformational conversion of syn-syn HONSO â anti-syn HONSO and reversible isomerization of HOSNO â anti-syn HONSO, syn-syn HONSO â HN(O)SO, HSONO â HS(O)NO, and HOSËËNO â HOSNO have also been observed, and the underlying mechanism is discussed.
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Introduction of surface defects and phase control engineering in the electrocatalytic system of overall water splitting has played a crucial role in significantly enhancing its electrocatalytic activity toward the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in water splitting, but the relationship between structure and electrocatalysis is still elusive. Herein, we report a solid-liquid method to induce surface reorganization (formation of a chalcogenide layer with rich chalcogenide vacancies) and phase transformation (Co9S8-to-Co3S4) simultaneously on cobalt chalcogenide. Featuring a uniform 2D morphology and the in situ formation of sulfur (S) vacancies, in a 0.1 M KOH solution, it exhibits a low overpotential of 288 mV vs. RHE at 10 mA cm-2, a low Tafel slope of 43.4 mV dec-1, and strong cycling stability (35 h), outperforming commercial RuO2 and most reported OER electrocatalysts. In addition, we also investigate the OER activity of the Co-S-P electrode in 1.0 M KOH solutions. Co0.37S0.38P0.02 NSs only need 257 mV to reach a current density of 10 mA cm-2. Meanwhile, the Tafel slope of Co0.37S0.38P0.02 NSs (44.0 mV dec-1) is lower than those of other recently reported electrocatalysts. Also, it shows high HER electrocatalytic activity in alkaline and acidic solutions. Finally, the Co0.37S0.38P0.02 electrode is used as a cathode and anode simultaneously for overall water splitting, which merely requires a cell voltage of 1.59 V at 10 mA cm-2 with excellent stability (40 h).
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The elusive hydrogen-bonded sulfur monoxide-hydroxyl radical complex (â¢OH···OS), a missing intermediate in the atmospheric chemistry of SO2, was generated in the 266 nm laser photolysis of the sulfinyl radical HOSO⢠in cryogenic Ar-matrixes. In addition to the IR spectroscopic characterization with deuteration, its thermal conversion to HOSO⢠with an activation barrier of 0.33 ± 0.11 kcal mol-1 (calcd 0.32 kcal mol-1, CCSD(T)-F12a/AVTZ) in the temperature range of 15.0-21.0 K and a H/D kinetic isotope effect of 2.4 at 16.0 K have been observed.
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Monomeric methyl metaphosphate (CH3OPO2), a highly electrophilic phosphorylating intermediate in chemical oligonucleotide synthesis, has been generated in the gas phase by high-vacuum flash pyrolysis (1000 K) of methyl 2-butenylphosphonate. In addition to the unambiguous characterization using IR spectroscopy in solid N2-, Ar-, and Ne-matrices, the formation CH3OPO2 in the photooxidation of the prototypical phosphinidene oxide CH3PO by O2 with 18O-isotope scrambling has been observed in the solid N2-matrix (15 K).
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Methoxyphosphinidene oxide (CH3 OPO) and isomeric methyldioxophosphorane (CH3 PO2 ) are key intermediates in the degradation of organophosphorus compounds (OPCs). Unlike the nitrogen analogues CH3 ONO and CH3 NO2 , the experimental data for these two prototypical OPCs are scarce. By high-vacuum flash pyrolysis (HVFP) of the diazide CH3 OP(O)(N3 )2 at 1000â K, the cis and trans conformers of CH3 OPO have been generated in the gas phase and subsequently isolated in cryogenic Ar and N2 matrices for IR spectroscopic characterization. Upon 266â nm laser irradiation of CH3 OPO, cisâtrans conformational conversion occurs with concurrent isomerization to CH3 PO2 . The spectroscopic identification of CH3 OPO and CH3 PO2 is supported by D-, 13 C-, and 18 O-isotope labeling and quantum chemical calculations at the CCSD(T)-F12a/cc-pVTZ-F12 level using configuration-selective vibrational configuration interaction (VCI).
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S-Nitrosothiols (RSNO) are exogenous and endogenous sources of nitric oxide in biological systems due to facile homolytic cleavage of the S-N bonds. By following the photolytic decomposition of prototypical RSNO (R = Me and Et) in Ne, Ar, and N2 matrixes (<10 K), elusive caged radical pairs consisting of nitric oxide (NOâ¢) and thiyl radicals (RSâ¢), bridged by O···S and H···N connections, were identified with IR and UV/vis spectroscopy. Upon red-light irradiation, both caged radical pairs (RS⢷··â¢ON) vanish and reform RSNO. According to the calculation at the CASPT2(10,8)/cc-pVDZ level (298.15 K), the dissociation energy of MeS⢷··â¢ON amounts to 4.7 kcal mol-1.
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The construction of a high efficiency and stable catalyst for use in electrochemical hydrogen generation has great significance for renewable energy technologies. Herein, we show for the first time that Ru decorated with NiCoP is an excellent hydrogen evolving catalyst in both acidic and alkaline conditions, close in performance to that of Pt/C.
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As representative two-dimensional (2D) materials, layered double hydroxides (LDHs) have received increasing attention in electrochemical energy storage and conversion because of the facile tunability between their composition and morphology. The high dispersion of active species in layered arrays, the simple exfoliation into monolayer nanosheets and chemical modification offer the LDHs an opportunity as active electrode materials in electrochemical capacitors (ECs). LDHs are favourable in providing large specific surface areas, good transport features as well as attractive physicochemical properties. In this review, our purpose is to provide a detailed summary of recent developments in the synthesis and electrochemical performance of the LDHs. Their composites with carbon (carbon quantum dots, carbon black, carbon nanotubes/nanofibers, graphene/graphene oxides), metals (nickel, platinum, silver), metal oxides (TiO2, Co3O4, CuO, MnO2, Fe3O4), metal sulfides/phosphides (CoS, NiCo2S4, NiP), MOFs (MOF derivatives) and polymers (PEDOT:PSS, PPy (polypyrrole), P(NIPAM-co-SPMA) and PET) are also discussed in this review. The relationship between structures and electrochemical properties as well as the associated charge-storage mechanisms is discussed. Moreover, challenges and prospects of the LDHs for high-performance ECs are presented. This review sheds light on the sustainable development of ECs with LDH based electrode materials.
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PURPOSE: The study aimed to assess the relationship between indium exposure and surfactant protein and any oxidative damage in indium tin oxide (ITO)-exposed workers. METHODS: The study was conducted in two typical ITO-manufacturing plants in Taiwan. One hundred and seventy manufacturing workers and 132 administrators were recruited. RESULTS: The geometric mean serum indium (S-In) level in the workers of the manufacturing department was 1.26 µg/l, which was significantly higher than those in the administrative department (0.72 µg/l). The S-In levels of 49 workers were higher than 3 µg/l (49/302, 16.2%), exceeding an occupational exposure limit suggested by the Japan Society for Occupational Health. Significant positive relationships were found between S-In and surfactant protein A (SP-A), and surfactant protein D (SP-D) levels. SP-A and SP-D levels were elevated significantly in the workers with moderately high indium exposure. CONCLUSION: The present study indicates a significant elevating trend of SP-A and SP-D levels in ITO-manufacturing workers, which are sensitive markers of interstitial lung disease. Though the indium exposure is not directly linked to all indicators of oxidative DNA damage, the ITO-manufacturing workplace is suggested to be related to oxidative DNA damage for the workers in the current study. Therefore, in addition to the indium exposure, there might be other occupational hazards in the ITO workplace to cause oxidative damage.