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BACKGROUND: Early and accurate identification of lymphatic node metastasis (LNM) and lymphatic vascular space invasion (LVSI) for endometrial cancer (EC) patients is important for treatment design, but difficult on multi-parametric MRI (mpMRI) images. PURPOSE: To develop a deep learning (DL) model to simultaneously identify of LNM and LVSI of EC from mpMRI images. STUDY TYPE: Retrospective. POPULATION: Six hundred twenty-one patients with histologically proven EC from two institutions, including 111 LNM-positive and 168 LVSI-positive, divided into training, internal, and external test cohorts of 398, 169, and 54 patients, respectively. FIELD STRENGTH/SEQUENCE: T2-weighted imaging (T2WI), contrast-enhanced T1WI (CE-T1WI), and diffusion-weighted imaging (DWI) were scanned with turbo spin-echo, gradient-echo, and two-dimensional echo-planar sequences, using either a 1.5 T or 3 T system. ASSESSMENT: EC lesions were manually delineated on T2WI by two radiologists and used to train an nnU-Net model for automatic segmentation. A multi-task DL model was developed to simultaneously identify LNM and LVSI positive status using the segmented EC lesion regions and T2WI, CE-T1WI, and DWI images as inputs. The performance of the model for LNM-positive diagnosis was compared with those of three radiologists in the external test cohort. STATISTICAL TESTS: Dice similarity coefficient (DSC) was used to evaluate segmentation results. Receiver Operating Characteristic (ROC) analysis was used to assess the performance of LNM and LVSI status identification. P value <0.05 was considered significant. RESULTS: EC lesion segmentation model achieved mean DSC values of 0.700 ± 0.25 and 0.693 ± 0.21 in the internal and external test cohorts, respectively. For LNM positive/LVSI positive identification, the proposed model achieved AUC values of 0.895/0.848, 0.806/0.795, and 0.804/0.728 in the training, internal, and external test cohorts, respectively, and better than those of three radiologists (AUC = 0.770/0.648/0.674). DATA CONCLUSION: The proposed model has potential to help clinicians to identify LNM and LVSI status of EC patients and improve treatment planning. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.
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In this study, three tetracoordinated bis(silylene) iron(II) chlorides, namely, [SiCHRSi]FeCl2 (1) (R = H), (2) (R = CH3), and (3) (R = Ph), were synthesized through the reactions of the three different bis(silylene) ligands [LSiCHRSiL] (L = PhC(NtBu)2, L1 (R = H), L2 (R = CH3), L3 (R = Ph)) with FeCl2·(THF)1.5 in THF. The bis(silylene) Fe complexes 1-3 could be used as effective catalysts for dinitrogen silylation, with complex 3 demonstrating the highest turnover number (TON) of 746 equiv among the three complexes. The catalytic mechanism was explored, revealing the involvement of the pentacoordinated bis(dinitrogen) iron(0) complexes [SiCHRSi]Fe(N2)2(THF), (4)-(6), as the active catalysts in the dinitrogen silylation reaction. Additionally, the cyclic silylene compound 10 was obtained from the reaction of L1 with KC8. Single-crystal X-ray diffraction analyses confirmed the molecular structures of complexes 1-3 and 10 in the solid state.
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In this study, a feature analysis and extraction method was proposed for specific emitter identification based on the signal generation mechanisms of radar transmitters. The generation of radar signals by radar transmitters was analyzed theoretically and experimentally. In the analysis, the main source of unintentional modulation in radar signals was identified, and the frequency stabilization of the solid-state frequency source, the nonlinear characteristics of the radio frequency amplifier chain, and the envelope of the pulse front edge were extracted as features for specific emitter identification. Subsequently, these characteristics were verified through simulation. The results revealed that the features extracted by this method exhibit "fingerprint characteristics" and can be used to identify specific radar emitters.
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Algoritmos , Radar , Simulación por Computador , Ondas de RadioRESUMEN
Background Endoscopic retrograde cholangiopancreatography (ERCP) is recommended by major guidelines for the removal of common bile duct (CBD) stones but is technically challenging in patients with low cardiopulmonary reserve and anatomic abnormalities of the upper gastrointestinal (GI) tract. Purpose To compare percutaneous transhepatic papillary balloon dilation (PTPBD) with ERCP for CBD stone removal. Materials and Methods Participants with one to three CBD stones (largest stone ≤30 mm) and without intrahepatic bile duct or gallbladder stones were eligible for this prospective cohort study. PTPBD was recommended in participants with low cardiopulmonary reserve or definitive anatomic abnormalities of the upper GI tract. Otherwise, both procedures were offered without preference. Follow-up, including abdominal CT, was conducted at 1-week and 1-, 3- and 6-month follow-up, and every 6 months thereafter. US and MR cholangiopancreatography were conducted if recurrence could not be confirmed with CT. Technical success rate was the primary outcome. Results A total of 531 participants were analyzed: there were 360 undergoing PTPBD (median age, 76 years; interquartile range [IQR], 64-82 years; 163 men) and 171 undergoing ERCP (median age, 66 years; IQR, 57-74 years; 94 men). The technical success rate was 99% (355 of 360) in the PTPBD group and 98% (167 of 171) in the ERCP group (relative risk, 1.02; P = .12). The incidence of overall complications was 4% (13 of 360) for PTPBD and 8% (13 of 171) for ERCP (relative risk, 0.27; 95% CI: 0.12, 0.61; P < .001). The PTPBD group showed a longer fluoroscopy time and a higher radiation exposure, with adjusted differences of 28.7 minutes (95% CI: 22.2, 35.2) and 384.3 mGy (95% CI: 296.5, 472), respectively. A propensity score-matching analysis (n = 123 per group) indicated that PTPBD had a slightly higher technical success rate and significantly fewer complications. Conclusion When compared with endoscopic retrograde cholangiopancreatography, percutaneous transhepatic papillary balloon dilation has a similar technical success rate and fewer perioperative complications but a higher radiation exposure. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by van Sonnenberg and Mueller in this issue.
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Colangiopancreatografia Retrógrada Endoscópica , Dilatación/métodos , Cálculos Biliares/cirugía , Anciano , Anciano de 80 o más Años , Femenino , Cálculos Biliares/diagnóstico por imagen , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios ProspectivosRESUMEN
Triarylboranes have attracted significantly increasing research interest as a remarkable class of photoelectronic π-electron materials. Because of the presence of vacant p orbital on the B center, the boryl group is a very unique electron acceptor that exhibits not only electron-accepting ability through p-π* conjugation but also high Lewis acidity to coordinate with Lewis bases and steric bulk arising from the aryl substituent on the B center to get enough kinetic stability. Thus, the incorporation of a trivalent B element into π-conjugated systems is an efficient strategy to tune the electronic and stereo structures and thus the photoelectronic properties of π-electron systems. When an electron-donating group, such as amino, is present, triarylboranes would likely display intramolecular charge-transfer transitions. These kinds of molecules are often highly emissive. In addition, the geometry of the molecules has a great impact on the emission properties. In this Forum Article, we herein describe our recent progress on the charge-transfer emitting triarylborane π-electron systems with novel geometries, which include the lateral boryl-substituted π-system with amino groups at the terminal positions, the o,o'-substituted biaryl π-system with boryl and amino groups at the o,o'-positions, a triarylborane-based BODIPY system, and a B,N/S-bridged ladder-type π-system. We mainly put the emphasis on the molecular design concept, structure-property relationships, intriguing emission properties and great applications of the corresponding triarylborane π-systems.
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OBJECTIVE: To investigate the safety and efficacy of trans-T tube duodenal papilla balloon dilatation for the removal of residual common bile duct stone after choledocholithotomy and T tube drainage. METHODS: Thirteen cases with residual common bile duct stone treated with trans-T tube duodenal papilla balloon dilatation in our department from June 2010 to April 2012 were analyzed retrospectively. Record CA19-9, bilirubin and albumin before the procedure, 1 week and 1 month later. Check if immediate complications occurs, including hemorrhage, perforation, pancreatitis and cholangitis. During the following up for 2 years, stone recurrence, reflux cholangitis and other long-term complications were observed. Analyze the changes of indicators between preoperative and postoperative and the correlation. RESULTS: All of the 13 patients were treated successfully. 11 patients underwent one procedure, and 2 patients received twice or more times of procedures. CA19-9 decreased significantly 1 week later and 1 month later compared with those before the procedure, while ALB was opposite. Incidences of biliary tract infection and hemorrhage were 1 and 1 respectively. No severe complications occurred, including perforation of gastrointestinal or biliary tract. Incidences of recurrent stone and reflux cholangeitis were 2 and 1 in two years after the procedure. CONCLUSIONS: Trans-T tube duodenal papilla balloon dilatation is a safe and effective procedure for patients with recurrent common bile duct stone after choledocholithotomy and T-tube drainage. For the cases which could not be handled with endoscopic procedures, it provides a new therapeutic approach.
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Colangiopancreatografia Retrógrada Endoscópica , Conducto Colédoco , Cálculos Biliares , Sistema Biliar , Cateterismo , Dilatación , Drenaje , Humanos , Periodo Posoperatorio , Recurrencia , Estudios RetrospectivosRESUMEN
The basic tribological experiments have reported that nano-graphene lubricating oil has excellent anti-friction and anti-wear properties, which has been widely concerned. However, the real anti-friction effect of nano-graphene lubricating oil and its impact on engine power performance, economic performance and emission performance remain to be proved. This has seriously hindered the popularization and application of nano-graphene lubricating oil in the engine field. In this paper, nano-graphene powder was chemically grafted to prepare nano-graphene lubricating oil with high dispersion stability. The influence of nano-graphene on physicochemical properties of lubricating oil was studied, and the influence of nano-graphene on engine power performance, economic performance and emission performance was explored. The results show that after modification, the dispersion of nano-graphene in lubricating oil is improved. Compared with pure lubricating oil, the addition of nano-graphene makes the kinematic viscosity of lubricating oil slightly lower, and has little effect on the density, flash point, pour point and total acid value of lubricating oil. The reversed towing torque of nano-graphene lubricating oil is reduced by 1.82-5.53%, indicating that the friction loss decreases. The specific fuel consumption of the engine is reduced, which indicates that the fuel economic performance is improved. Engine HC+NOX, CH4, CO2 emissions do not change much, but particulate matter (PM) emissions increase by 8.85%. The quantity concentration of nuclear particles, accumulated particles and total particles of nano-graphene lubricating oil are significantly higher than that of pure lubricating oil. And the increase of the quantity concentration of accumulated particles is more obvious than that of nuclear particles, and the larger the load, the more obvious this phenomenon. In order to apply nano-graphene lubricating oil to the engine, it is also necessary to further study its impact on the post-processing system, adjust the control strategy of the post-processing system and then test and calibrate.
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Grafito , Lubricantes , Viscosidad , Grafito/química , Lubricantes/química , Gasolina/análisis , Nanoestructuras/química , Aceites/química , Lubrificación , Emisiones de Vehículos/análisisRESUMEN
Nano-graphene lubricating oil with appropriate concentration shows excellent performance in reducing friction and wear under different working conditions of diesel engines, and has been widely concerned. Lubricating oil has a significant impact on particulate matter (PM) emissions. At present, there are few studies on the impact of nano-graphene lubricating oil on the physicochemical properties of PM. In order to comprehensively evaluate the impact of nano-graphene lubricating oil on diesel engines, this paper mainly focused on the effects of lubricating oil nano-graphene additives on the particle size distribution and physicochemical properties of PM. The results show that, compared with pure lubricating oil, the total number of nuclear PM and accumulated PM of nano-graphene lubricating oil is significantly increased. The fractal dimension of PM of nano-graphene lubricating oil increases and its structure becomes more compact. The average fringe separation distance of basic carbon particles decreases, the average fringe length increases. The degree of ordering and graphitization of basic carbon particles are higher. The fringe tortuosity of basic carbon particles decreases, and the fluctuation of carbon layer structure of basic carbon particles decreases. Aliphatic substances in PM are basically unchanged, aromatic components and oxygen functional groups increase. The initial PM oxidation temperature and burnout temperature increase, the maximum oxidation rate temperature and combustion characteristic index decrease, and the activation energy increases, making it more difficult to oxidize. This was mainly caused by the higher graphitization degree of PM of nano-graphene lubricating oil and the increased content of aromatic substances.
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BACKGROUND: Endometrial Cancer (EC) is a highly heterogeneous cancer comprising both histological and molecular subtypes. Using a non-invasive modality method to trigger these subtypes as early as possible can aid clinicians in establishing individualized treatment. PURPOSE: The study aimed to clarify the value of the Apparent Diffusion Coefficient (ADC) of EC MRI in determining molecular subtypes. MATERIAL AND METHODS: We retrospectively recruited 109 patients with pathologically proven EC (78 endometrioid cancers and 31 non-endometrioid cancers) with available molecular classification from a tertiary centre. MRI was prospectively performed a month prior to surgery; images were blindly interpreted by two experienced radiologists with consensus reading. The ADC value was measured by an experienced radiologist on the commercially available processing workstation. Interoperator measurement consistency was calculated. RESULTS: Our sample comprised 17 PLOE, 32 MSI-H, 31 NSMP, and 29 P53abn ECs. Clinical information did not differ significantly among the groups. The maximum diameter and volume of the lesions differed among the groups. The ADC value in the maximal area (ADCarea) or region of interest (ROI, ADCroi) in the P53abn group was higher than that in the other groups (894.0 ±12.6 and 817.5 ± 83.3 x10-6 mm2/s). The ADC mean values were significantly different between the P53abn group and the other groups (P = 0.000). The nomogram showed the highest discriminative ability to distinguish P53abn EC from other types (AUC: 0.859). CONCLUSION: Our results have suggested the quantitative MR characteristics (ADC values) derived from preoperative EC MRI to provide useful information in preoperatively determining P53abn cancer.
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Imagen de Difusión por Resonancia Magnética , Neoplasias Endometriales , Proteína p53 Supresora de Tumor , Humanos , Femenino , Neoplasias Endometriales/diagnóstico por imagen , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Imagen de Difusión por Resonancia Magnética/métodos , Adulto , Carcinoma Endometrioide/diagnóstico por imagenRESUMEN
OBJECTIVES: To identify lymphatic vascular space invasion (LVSI) and lymphatic node metastasis (LNM) status of endometrial cancer (EC) patients, using radiomics based on MRI images. METHODS: Five hundred and ninety-eight EC patients between January 2015 and September 2020 from two institutions were retrospectively included. Tumoral regions on DWI, T1CE, and T2W images were manually outlined. Radiomics features were extracted from tumor region and peri-tumor region of different thicknesses. We established sub-models to select features from each smaller category. Using this method, we separately constructed radiomic signatures for intra-tumoral and peri-tumoral images using different sequences. We constructed intra-tumoral and peri-tumoral models by combining their features, and a multi-sequence model by combining logits. Models were trained with 397 patients and validated with 170 internal and 31 external patients. RESULTS: For LVSI positive/LNM positive status identification, the multi-parameter MRI radiomics model achieved the area under curve (AUC) values of 0.771 (95%CI: [0.692-0.849])/0.801 (95%CI: [0.704, 0.898]) and 0.864 (95%CI: [0.728-1.000])/0.976 (95%CI: [0.919, 1.000]) in internal and external test cohorts, respectively. CONCLUSIONS: Intra-tumoral and peri-tumoral radiomics signatures based on mpMRI can both be used to identify LVSI or LNM status in EC patients non-invasively. Further studies on LVSI and LNM should pay attention to both of them.
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Oil exploitation may pose adverse effects on marine ecosystems, but its impacts on surface carbonate dynamics remain unknown. In a carbonate system with low air-sea ∆pCO2, such as the South China Sea (SCS), human activities may affect the pCO2 distribution patterns and potentially alter CO2 sink or source at the surface. This study investigates the surface carbonate system in two oil fields, namely the Wenchang Oil Feld and Enping Oil Feld, located on the northwestern SCS (NWSCS) shelf. In Enping Oil Field, although there is a slight increase in surface pCO2 due to probable total alkalinity (TA) consumption from CaCO3 precipitation, strong biological production makes the plume water a strong CO2 sink. Similarly, the biological processes dominated the pCO2 variability in Wenchang Oil Feld, exhibiting high values in its central area. In NWSCS, the influence of shelf water was observed during both cruises. And the pCO2 drawdown caused by the decreased sea surface temperature (SST) and CO2 outgassing outweighed their increases via enhanced vertical mixing, leading to a pCO2 drawdown from September to October within this water mass. More importantly, there were no significant disparities observed in carbonate parameters at stations along transects with and without wells, and the observed parameter values in this study fell within the range reported previously on the nSCS shelf with similar controlling processes. Thus the impact of oil exploitation on carbonate dynamics is negligible, and the characteristics of the carbonate system in oil field are primarily governed by natural processes such as the mixing of plume water and basin water, CaCO3 precipitation and the changes in SST. The provided data establish a crucial baseline for detecting future alterations in carbonate chemistry within oil fields, and the rapid fluctuations in sea surface pCO2 highlight the need for higher spatiotemporal resolution observation.
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Hyperspectral technology, with its high spectrum resolution and nanometer continuous spectral information acquisition ability, provide a possibility for rapidly and nondestructive evaluating compost maturity. In this study, the near-infrared spectroscopy (NIRS) analysis techniques was used to analyze quantitatively organic matter (OM) content, total nitrogen (TN) content and carbon-nitrogen (C/N) ratio in compost based on two different composting procedures. In the basis of spectra preprocessing and strategies of variable selection, the nonlinear modeling LBC-siPLS-PLSR for OM, MSC-SPA-PLSR for TN and R-SPA-PLSR for C/N ratio was respectively constructed using partial least squares regression (PLSR). LBC-siPLS-PLSR, MSC-SPA-PLSR and R-SPA-PLSR provided a better prediction capability with root mean square error of prediction, the coefficient of determination for prediction and residual predictive deviation values of 4.061, 0.746 and 2.02 for OM, values of 0.205, 0.65 and 1.71 for TN and values of 1.11, 0.706 and 2.07 for C/N ratio, respectively. These results showed that the NIRS technique could be fitted to each element, using specific spectrum pretreatment, in order to achieve an acceptable accuracy in the prediction.
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Heavy metals in sediments and waters in the Chukchi Plateau and adjacent waters were investigated in this study. The results showed that most metals (especially Ni, As and Co) have accumulated in sediments, and their levels followed the order of Zn > Ni > Co > Cr > Cu > As > Pb > Cd. Spatial variations of environmental variables and metal characteristics were revealed based on the transect research. Furthermore, heavy metal concentrations presented vertical variations in water column with the levels of Ni > As > Zn > Cu > Cr > Pb > Cd > Co, and they were inhomogeneous in different water masses. This paper will be helpful to the study of the pollution and distribution of the heavy metals in Arctic Ocean and its surrounding environment.
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Metales Pesados , Contaminantes Químicos del Agua , Sedimentos Geológicos , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Cadmio , Plomo , Metales Pesados/análisis , Agua , Medición de Riesgo , ChinaRESUMEN
Surface sediment samples were collected from Daya Bay in October 2018, and analyzed for total organic carbon (OC), total nitrogen (TN) and their stable isotopes (δ13C and δ15N), total phosphorus (TP), biogenic silica (BSi), sediment textures and specific surface area (SSA). The primary objective was to evaluate the influence of mariculture/aquaculture on the distribution characteristics of organic matter (OM), and preservation status of OC, TN, TP, and BSi in sediments. The average δ13C and δ15N values, and OC/TN ratios were -21.27, 6.74, and 8.90, respectively. Monte Carlo simulation results revealed that mariculture/aquaculture biodeposits accounted for >40% of the buried OM at sites where the breeding rafts and cages are located, whereas marine OM increased gradually to the open sea. Terrestrial OM was generally low accounting for 17% by average. The contents and distribution characteristics of biogenic elements were more influenced by mariculture/aquaculture and primary productivity than sediment textures. Lower OC/SSA (0.3-1.2 mg OC/m2), TN/SSA (~0.05-0.18 mg TN/m2), and TP/SSA (0.02-0.04 mg TP/m2) loadings indicated that increased sequestration of labile OM in a coastal bay could contribute to significant degradation of recalcitrant OM in sediments with significant loss of P relative to OC. Nitrogen contamination in surface sediments was due to increased injection of aquaculture biodeposits, and may pose a detrimental effect on the ecological sustainability of the bay. Higher BSi/SSA loadings (0.9-1.7 mg BSi/m2) revealed that BSi was more preserved, and that BSi-based proxy could be used for paleo-productivity studies. However, such preservation may induce adverse dissolved silicate limitation in a bay perturbed by eutrophication. Fine-grained sediments (clay and silt) accounted for >77% of the sediment texture types with higher SSA, and while controlling the contents of biogenic elements under given depositional conditions were not the main determining factors of OC, TN, TP, and BSi preservation.
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In this paper, a novel portable hard-disk encryption/decryption system with a MEMS coded lock is presented, which can authenticate the user and provide the key for the AES encryption/decryption module. The portable hard-disk encryption/decryption system is composed of the authentication module, the USB portable hard-disk interface card, the ATA protocol command decoder module, the data encryption/decryption module, the cipher key management module, the MEMS coded lock controlling circuit module, the MEMS coded lock and the hard disk. The ATA protocol circuit, the MEMS control circuit and AES encryption/decryption circuit are designed and realized by FPGA(Field Programmable Gate Array). The MEMS coded lock with two couplers and two groups of counter-meshing-gears (CMGs) are fabricated by a LIGA-like process and precision engineering method. The whole prototype was fabricated and tested. The test results show that the user's password could be correctly discriminated by the MEMS coded lock, and the AES encryption module could get the key from the MEMS coded lock. Moreover, the data in the hard-disk could be encrypted or decrypted, and the read-write speed of the dataflow could reach 17 MB/s in Ultra DMA mode.
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Two new triarylborane-based o,o'-substituted 2,2'-bithienyls, BT-BNMe 2 and BT-BNBn 2 , which contain BMes2 and NMe2/NBn2 groups at the 3,3'-positions, have been synthesized. Similar to the o,o'-substituted biphenyl analogues, BP-BNMe 2 and BP-BNBn 2 , which contain BMes2 and NMe2/NBn2 groups at the 2,2'-positions, the steric effect of the amino group has significant influence on the conformation of the 2,2'-bithienyl skeleton. The boryl and amino groups are located at the same side of 2,2'-bithienyls axis with a short B···N distance (3.63 Å) for the NMe2-substituted BT-BNMe 2 . On the contrary, the two substituents are arranged on the two different sides of the 2,2'-bithienyls axis for BT-BNBn 2 , which is modified with bulky NBn2. Despite the remarkable differences in the steric structure, the two 2,2'-bithienyls display fluorescence at close wavelengths, which is in sharp contrast to the much red-shifted fluorescence of BP-BNMe 2 than BP-BNBn 2 . The theoretical calculations demonstrated that the two 2,2'-bithienyls have close highest occupied molecular orbital-lowest unoccupied molecular orbital gaps in the excited state, which firmly support the experimental results. Thus, the parent main chain framework can exhibit great impact on the charge-transfer emission of o,o'-substituted biaryls.
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A triarylborane-based biphenyl, 4,4'-dibromo-2-dimesitylboryl-2'-(N,N-dimethylamino)biphenyl (Br2-BN-BPh), exhibits very unique temperature-dependent fluorescence behavior. Although Br2-BN-BPh is weakly emissive at room temperature, its fluorescence increases abruptly at a specific high temperature (68 °C in MOE, 88 °C in toluene). In addition, the fluorescence still remains very strong even after cooling to room temperature, providing the possibility of the fluorescence detection of a specific high temperature.
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BACKGROUND: The aim of the present study was to assess the quality of diabetes care and characteristics of the healthcare system in underdeveloped rural mountain areas of western China. METHODS: Questionnaires were used to collect data from 288 diabetic patients with a multistage cluster sampling method in Zhongjiang County (Sichuan Province) between October 2009 and April 2010. Sixty-two village clinics, 23 town health centers, and a county central hospital were included to assess the availability of diabetes-related medical resources, in addition to diabetes-related medical insurance, reimbursement policies, and manpower. RESULTS: Of 288 patients, 38.2 % monitored their blood glucose regularly. Targets for fasting blood glucose (≤7 mmol/L) and blood pressure (≤130/80 mmHg) were achieved by 7.6 % and 9.7 % of patients, respectively. On average, each patient paid US$120 out of pocket annually for out-patient diabetes care, with a maximum US$86 reimbursed. The county central hospital was the only healthcare facility in the county that could provide all essential diabetes-related drugs and process-of-care measures and tests, except measures of HbA1c and the urinary albumin: creatinine ratio. Insulin was not available at village clinics, and only 29 % of village clinics had glucometers. "Certified" doctors were not available to provide primary care in village clinics. CONCLUSIONS: The quality of diabetes care was quite poor in underdeveloped rural mountain areas of western China. Recommendations for further intervention research to improve diabetes healthcare include increasing investment in medical infrastructure, improving the availability of essential drugs and process measures, organizing regular diabetes patient education, and recruiting village doctors.
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Diabetes Mellitus/tratamiento farmacológico , Accesibilidad a los Servicios de Salud/normas , Atención Primaria de Salud/estadística & datos numéricos , Salud Rural/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Pueblo Asiatico/estadística & datos numéricos , Glucemia/análisis , Presión Sanguínea , China , Estudios Transversales , Diabetes Mellitus/sangre , Diabetes Mellitus/etnología , Femenino , Hemoglobina Glucada/análisis , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Atención Primaria de Salud/métodos , Encuestas y CuestionariosRESUMEN
Congener profiles, distribution and sources of parent and alkyl-polycyclic aromatic hydrocarbons (PAHs) in surface sediments of Southern Yellow Sea (SYS), China were investigated. The ecological risk of parent-PAHs to aquatic organisms were evaluated based on sediment quality guidelines (SQGs), risk quotient (RQ), organic carbon (OC)-normalized analysis and mean effects range-median quotient (M-ERM-Q). The concentrations of 33 PAHs were analyzed, including 14 parent PAHs (without naphthalene and acenaphthylene), 16 alkyl-PAHs (7 methylphenanthrenes, 3 methylanthracenes, 3 methylfluoranthenes, and 3 methylpyrenes), dibenzothiophene, retene and perylene. Total concentrations of PAHs (TPAHs) ranged from 200.8 to 3629.0ng/g dry weight (d.w.), with a mean value of 1035.4ng/g d.w., and mainly contributed by fluorene, phenanthrene, methylphenanthrene, retene, fluoranthene and pyrene. Analysis of a broad variety of diagnostic ratios suggested that combustion was the key source of PAHs. Principal component analysis-multiple linear regression (PCA-MLR) indicated that combustion of coal, softwood and nature gas, coke oven, petroleum and vehicle emission were the main sources of PAHs in sediments of SYS, contributing 41.5%, 30.6%, 18.8%, and 9.0% to TPAHs, respectively. Ecological risk assessment of individual parent-PAHs suggested that fluorene, phenanthrene and fluoranthene may cause some risk to aquatic organisms in some stations. OC-normalized analysis and M-ERM-Q indicated that risk of multiple parent-PAHs was quite low in the studied area.
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Monitoreo del Ambiente , Sedimentos Geológicos/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminantes Químicos del Agua/análisis , China , Océanos y Mares , Medición de RiesgoRESUMEN
BACKGROUND: Percutaneous brachytherapy is a valuable method for the treatment of lung cancer and mediastinal lymph nodes metastasis. However, in some of the metastatic lymph nodes in the middle mediastinum, the percutaneous approach cannot be used safely due to possible damage to surrounding anatomical structures. We established an animal model (group of 12 pigs) to assess the safety and feasibility of computed tomography (CT)-guided vena cava puncture. METHODS: Under CT guidance, an 18G needle was used to puncture the anterior wall of the anterior vena cava (AVC) in 12 pigs. The 18G needle was chosen as it is similar in size to the needles employed for clinical application in brachytherapy. The incidence of complications and vital signs was monitored during the procedure. Thoracotomy was performed to remove AVC specimens, which were analyzed for histological evidence of vessel wall damage and repair. RESULTS: Following postoperative enhanced CT, two animals were found to have a small pneumothorax (one being hemopneumothorax). The intraoperative oxygen saturation of both animals was not significantly decreased and was maintained at 93-100%. No animals developed mediastinal hematoma. Preoperative, intraoperative, and postoperative changes in blood pressure, heart rate, hemoglobin, and blood oxygen saturation were not significant. Histological evaluation of AVC specimens showed that by 7 days following the procedure, the endothelial layer was smooth with notable scar repair in the muscularis layer. CONCLUSIONS: CT performed after the procedure and histological preparations confirmed the safety of the procedure. This indicates that percutaneous brachytherapy for metastatic middle mediastinal lymph nodes can be carried out via the superior vena cava.