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1.
Langmuir ; 38(46): 14172-14184, 2022 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-36367785

RESUMEN

Research on the dispersion and stability of nanoparticles in liquid media is one of the key subjects for nanomaterial utilization. In consideration of the preponderance of coarse-grained (CG) molecular dynamics (MD) simulation in following and understanding the structure and dynamics on the nanoscale, an improved CG model for nanoparticles based on the Martini force field is established to facilitate the more extensive applications of this simulation method and further studies on complex nanoparticle liquid systems. Gel ink is selected as the liquid system for nanoparticles to validate the improved CG model on the one hand and introduce the CGMD simulation method into the studies of this system on the other. The calculation shows that the improved model can provide relatively precise results and has good computational stability. The effect mechanisms of the thickener and disperser on the carbon black nanoparticle are similar, namely the result of a delicate balance between the interaction of the thickener/disperser with the carbon black nanoparticle and the interaction of the thickener and disperser with each other. Furthermore, the phase assimilating effect of disperser molecules is key for separating the agglomerated carbon black nanoparticles; thereafter, the space steric hindrance effect and the electrostatic hindrance effect play main roles in maintaining the dispersion of carbon black nanoparticles.


Asunto(s)
Simulación de Dinámica Molecular , Nanopartículas , Humanos , Hollín , Tinta , Nanopartículas/química , Electricidad Estática
2.
Br J Nutr ; 128(9): 1798-1805, 2022 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-34776040

RESUMEN

Excessive iodine can lead to goiters. However, the relationship between the water iodine concentration (WIC) and goiter rate (GR) is unclear. This study aims to explore the factors that influence children's GR in areas with high WIC and analyse the threshold value of the GR increase associated with the WIC. According to the monitoring of the areas with high WIC in China in 2018-2020, a total of 54 050 children in eight high water iodine provinces were chosen. Drinking water, urine and edible salt samples of children were collected. The thyroid volume (Tvol) was measured. A generalised additive model (GAM) was used to analyse the relationship between the WIC and GR in children. Among the 54 050 children in areas with high WIC, the overall GR was 3·34 %, the median of water iodine concentration was 127·0 µg/l, the median of urinary iodine concentration was 318 µg/l and the non-iodised salt coverage rate (NISCR) was 63·51 %. According to the GAM analysis results, water iodine and urinary iodine are factors that influence the Tvol and GR, while the NISCR affects only the GR. When the WIC was more than 420 µg/l or the urinary iodine concentration was more than 800 µg/l, the GR increased rapidly. When the NISCR reached more than 85 %, the GR was the lowest. Thus, in areas with high WIC, WIC more than 420 µg/l may increase the risk of goiter, and the NISCR should be increased to over 85 % to avoid goiters in children.


Asunto(s)
Agua Potable , Bocio , Yodo , Humanos , Niño , Yodo/análisis , Agua Potable/análisis , Cloruro de Sodio Dietético/análisis , China , Prevalencia
3.
Front Chem ; 9: 704012, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34249872

RESUMEN

Laterite ore is one of the important sources of nickel (Ni). However, it is difficult to liberate Ni from ore structure during reduction roasting. This paper provided an effective way for a robust recovery of Ni from laterite ore by H2 reduction using sodium thiosulfate (Na2S2O3) as a promoter. . It was found that a Ni content of 9.97% and a Ni recovery of 99.24% were achieved with 20 wt% Na2S2O3 at 1,100°C. The promoting mechanism of Na2S2O3 in laterite ore reduction by H2 was also investigated. The thermogravimetric results suggested the formation of Na2Mg2SiO7, Na2SO3, Na2SO4, and S during the pyrolysis of laterite with Na2S2O3, among which the alkali metal salts could destroy the structures of nickel-bearing silicate minerals and hence release Ni, while S could participate in the formation of the low-melting-point eutectic phase of FeS-Fe. The formation of low-melting-point phases were further verified by the morphology analysis, which could improve the aggregation of Ni-Fe particles due to the capillary forces of FeS-Fe as well as the enhanced element migration by the liquid phase of sodium silicates during reduction.

4.
Thyroid ; 30(10): 1535-1540, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32245343

RESUMEN

Background: The appropriate range of median urinary iodine concentration (MUI) in children has always been controversial. To prevent the occurrence of a goiter epidemic in Shanghai, we explored the appropriate range of MUI by integrating multiple monitoring results. Methods: This study summarized and analyzed the monitoring data from 1997, 1999, 2011, 2014, and 2017 of children living in Shanghai. In each monitoring year, the probability-proportional-to-size sampling technique was used to select 30 sampling units. In each sampling unit, one primary school was randomly selected. From each selected school, 40 children 8- to 10-year-old were randomly recruited to measure thyroid volume (Tvol) and their household salt iodine intake. Results: In 1997, 1999, 2011, 2014, and 2017, MUI of 8- to 10-year-old children was 228, 214, 182, 171, and 183 µg/L, and median Tvol (MTvol) was 2.9, 1.2, 1.0, 1.8, and 2.8 mL, respectively. There was a linear correlation between goiter rate and MTvol (r = 0.95, p = 0.014; 100 × goiter rate = 1.314 × MTvol -1.287). Generalized additive model (GAM) was used to predict MTvol as follows, MTvol = 0.60689 + 0.00302 MUI +0.999928 s (MUI) -0.05172 mean salt iodized concentrations (MSIs) +0.03481 × 100 × iodized salt coverage rate +0.00000969 per capita disposable income +0.271422 s (per capita disposable income) -0.38772 × monitoring year gap. The results revealed that the average relative error between predicted and actual value was 15.2%. GAM results showed that at 27-277 µg/L MUI, the goiter rate was <5%. Conclusions: Iodine status is appropriate in Shanghai. Under the existing economy and MSI, the optimal range of MUI should be 70-277 µg/L in 8- to 10-year-old children living in Shanghai.


Asunto(s)
Bocio/prevención & control , Yodo/orina , Cloruro de Sodio Dietético/uso terapéutico , Niño , China/epidemiología , Humanos , Yodo/uso terapéutico , Estado Nutricional , Tamaño de los Órganos , Control de Calidad , Valores de Referencia , Glándula Tiroides/fisiología
5.
ACS Omega ; 5(6): 3047-3054, 2020 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-32095728

RESUMEN

A large amount of sulfur dioxide (SO2) will be released during rural household coal combustion, causing serious environmental pollution. Therefore, it is very urgent to develop a clean and efficient fuel to substitute rural household coal controlling SO2 emission. In this paper, a new strategy toward scattered coal combustion with remarkably reducing SO2 emission was proposed. Coal and compound additive of Al2O3 and CaCO3 were blended and then copyrolysis at 1050 °C was performed to produce clean coke. First, the sulfur content of clean coke was reduced, meanwhile, generating sulfur fixation precursor during pyrolysis. Then, clean coke is used for efficient sulfur fixation during the subsequent combustion process to reduce SO2 emissions. The effects of combustion temperature, Al/S molar ratio, and the mechanism of sulfur retention during clean coke combustion were studied in the tube furnace and muffle furnace. The mechanism can be attributed the following reason: (a) CaS produced during pyrolysis and CaO decomposed by complex additives were oxidized during combustion, and CaO captured the SO2 released from clean coke combustion, which formed CaSO4. (b) CaSO4 reacts with Al2O3 to produce calcium sulfoaluminate at high temperatures, which improves the sulfur fixation efficiency of clean coke combustion at high temperatures. In a word, this new strategy can greatly reduce the emission of SO2, thus helping to solve rural household coal pollution problems.

7.
Biol Trace Elem Res ; 193(1): 36-43, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30840185

RESUMEN

The objectives of this study were to explore reference intervals of ratios of concentrations of urinary iodine to creatinine (UIC/UCr) in pregnant women, to determine specific reference intervals for thyroid hormone concentrations (FT3, FT4, TSH) in the first trimester of pregnancy, and provide a comprehensive evaluation of iodine nutritional status and thyroid function. Cross-sectional data analysis, including questionnaires and thyroid ultrasonograms, were used to exclude subjects who had a history of thyroid disease, a family history of thyroid disease, or thyroid morphological abnormalities. Tests of thyroid hormone were evaluated together with urinary iodine concentration (UIC), urinary creatinine concentration (UCr), and salt iodine concentration in pregnant women. For the sample of pregnant women eligible for inclusion, the 95% reference intervals of the bilateral limits of UIC/UCr and thyroid hormone concentrations in pregnant women were determined by the percentile method. Pregnant women were recruited in Harbin, Heilongjiang Province, a particular geographical area of China, where iodine nutrition is adequate. The median UIC was 141.47 µg/L, while the median UIC/UCr was 141.12 µg/g. The reference intervals of thyroid hormone concentrations in the first trimester were FT3 3.63-6.12 pmol/L, FT4 11.89-22.91 pmol/L, and TSH 0.013-3.814 mIU/L. The reference intervals of UIC/UCr were 52.47 to 532.09 µg/g (first trimester 47.25-353.91 µg/g, second trimester 57.95-639.08 µg/g, third trimester 46.98-494.73 µg/g).The established UIC/UCr medical reference intervals and thyroid hormone concentration reference intervals may be used for iodine nutritional assessment and thyroid disease screening in pregnant women.


Asunto(s)
Yodo/orina , Primer Trimestre del Embarazo , Embarazo , Hormonas Tiroideas/sangre , Adulto , China , Creatinina/orina , Femenino , Humanos , Embarazo/sangre , Embarazo/orina , Primer Trimestre del Embarazo/sangre , Primer Trimestre del Embarazo/orina
8.
Nutr J ; 18(1): 63, 2019 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-31677639

RESUMEN

BACKGROUND: In 1996, Shanghai implemented universal salt iodization and has became the last provincial unit in China to carry out this intervention. In this study, we summarized achievements in past 20 years, to provide suggestions and evidence for the next stage of iodine supplementation. METHODS: This study summarized and analyzed monitoring data of children from 1997, 1999, 2005, 2011, 2014, and 2017 in Shanghai. In each monitoring year, 30 streets or towns were selected using the probability-proportional-to-size sampling technique. One primary school was selected from each street or town by a simple random sampling technique. From each school, 40 children aged 8 to 10 years were randomly selected. The number of children was divided equally by sex and age. RESULTS: In 1997, 1999, 2005, 2011, 2014, and 2017, median urinary iodine (MUI) was 227.5 µg/L, 214.3 µg/L, 198.1 µg/L, 181.6 µg/L, 171.4 µg/L, and 183.0 µg/L, goiter rate was 3.07, 0.40, 0.08, 0.08, 0.86, and 1.90%, and median thyroid volume (MTvol) was 2.9 mL, 1.2 mL, 2.4 mL, 1.0 mL, 1.8 mL, and 2.8 mL, respectively. There was a linear correlation between goiter rate and median thyroid volume (MTvol) (r = 0.95, P = 0.014). Household salt iodine concentration (SIC) was dropping every monitoring (P < 0.05). There was a significant difference among different household SIC groups in MUI in 1999 and 2017, and in MTvol in 1999 (P < 0.05). No significant differences were detected in the other years. CONCLUSIONS: In Shanghai, the iodine status of 8 to 10 years old children is adequate. Household SIC have little effect on iodine status of children. Future studies should analyze the dietary sources of iodine, especially from pre-packaged and prepared-away-from-home foods or meals. The regular monitoring of iodine status is important to human health.


Asunto(s)
Suplementos Dietéticos/estadística & datos numéricos , Yodo/orina , Política Nutricional , Estado Nutricional , Cloruro de Sodio Dietético/administración & dosificación , Niño , China/epidemiología , Femenino , Estudios de Seguimiento , Bocio/epidemiología , Humanos , Yodo/administración & dosificación , Masculino , Tamaño de los Órganos , Glándula Tiroides/anatomía & histología
9.
Sensors (Basel) ; 19(1)2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30609667

RESUMEN

In this paper, we consider the problem of decision fusion for noncoherent detection in a wireless sensor network. Novel to the current work is the integration of the hybrid multi-access channel (MAC) in the fusion rule design. We assume that sensors transmit their local binary decisions over a hybrid MAC which is a composite of conventional orthogonal and nonorthogonal MACs. Under Rayleigh fading scenario, we present a likelihood ratio (LR)-based fusion rule, which has been shown to be optimal through theoretical analysis and simulation. However, it requires a large amount of computation, which is not easily implemented in resource-constrained sensor networks. Therefore, three sub-optimal alternatives with low-complexity are proposed, namely the weighed energy detector (WED), the deflection-coefficient-maximization (DCM), and the two-step (TS) rules. We show that when the channel signal-to-noise ratio (SNR) is low, the LR-based fusion rule reduces to the WED rule; at high-channel SNR, it is equivalent to the TS rule; and at moderate-channel SNR, it can be approached closely by the DCM rule. Compared with the conventional orthogonal and nonorthogonal MACs, numerical results show that the hybrid MAC with the proposed fusion rules can improve the detection performance when the channel SNR is medium.

10.
Biol Trace Elem Res ; 187(1): 59-64, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29730749

RESUMEN

Both Shanghai and Switzerland are developed regions with long-standing salt iodization programs and periodic monitoring. However, the two regions have their own approach to the implementation of the iodized salt policy. In Shanghai, monitoring was carried out every few years, using probability-proportional-to-size sampling technique to select 30 sampling units. Each unit consisted of more than 12 pregnant women and one randomly selected primary school. Urine samples were then taken from the chosen pregnant women and randomly recruited students of that school for iodine test. Data of Switzerland used in this comparative study was extracted from published researches. In Shanghai, the median urinary iodine concentration (UIC) in 2014 was 20% lower than in 1999 (P < 0.05). The median UIC of pregnant women in 2014 was 9.5% lower than that in 2011 (P < 0.05). In terms of iodized salt concentration, opposite to the increasing in Switzerland, it has exhibited a downward trend in Shanghai (P < 0.05). For the years monitored, the iodized salt concentration in Shanghai was significantly (P < 0.05) higher than in Switzerland. Though the UIC of children exhibited a downward trend in Shanghai (P < 0.05), it was still significantly (P < 0.05) higher than in Switzerland over the same monitoring period. However, the UIC in pregnant women was a totally different story, which was significantly (P < 0.05) lower in Shanghai than in Switzerland. Iodized salt is very important for maintaining sufficient iodine level in the population. Appropriate concentration of iodine in fortified salt needs to be decided according to local conditions. Special attention should be paid to the iodine level of pregnant women in Shanghai, and more education about iodine is necessary for the public health.


Asunto(s)
Yodo/orina , Cloruro de Sodio Dietético/orina , China , Femenino , Humanos , Yodo/deficiencia , Embarazo , Suiza
11.
Br J Nutr ; 119(11): 1245-1253, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29580306

RESUMEN

Universal salt iodisation (USI) has been successfully implemented in China for more than 15 years. Recent evidence suggests that the definition of 'adequate iodine' (100-199 µg/l) be revised to 'sufficient iodine' (100-299 µg/l) based on the median urinary iodine concentration (MUI) in school-age children. The objective of this study was to determine the prevalence of thyroid dysfunction in populations after long-term salt iodisation and examine whether the definition of adequate iodine can be broadened to sufficient iodine based on the thyroid function in four population groups. A cross-sectional survey was conducted in six provinces in the northern, central and southern regions of China. Four population groups consisting of 657 children, 755 adults, 347 pregnant women and 348 lactating women were recruited. Three spot urinary samples were collected over a 10-d period and blood samples were collected on the 1st day. In the study, among the adults, pregnant women and lactating women, the prevalence rates of elevated thyroglobulin antibody and thyroid microsomal antibody levels were 12·4, 8·5 and 7·8 %, and 12·1, 9·1 and 9·1 %, respectively. Abnormally high thyroid dysfunction prevalence was not observed after more than 15 years of USI in China because the thyroid dysfunction rates were all <5 %. The recommended range should be cautiously broadened from adequate iodine to sufficient iodine according to the MUI of school-age children considering the high levels of hormones and antibodies in the other populations. Adults, particularly pregnant women positive for thyroid antibodies, should be closely monitored.


Asunto(s)
Autoanticuerpos/sangre , Yodo/administración & dosificación , Lactancia/fisiología , Cloruro de Sodio Dietético/administración & dosificación , Glándula Tiroides/efectos de los fármacos , Adolescente , Adulto , Niño , China/epidemiología , Estudios Transversales , Femenino , Humanos , Hipotiroidismo/epidemiología , Hipotiroidismo/prevención & control , Yodo/orina , Masculino , Persona de Mediana Edad , Embarazo , Tiroglobulina/inmunología , Glándula Tiroides/fisiología , Adulto Joven
12.
Biol Trace Elem Res ; 185(2): 275-281, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29541993

RESUMEN

In Shanghai, a new iodized salt standard was implemented in 2012. To provide evidence to the government, we compared iodine status before (35 mg/kg) and after (30 mg/kg) adjustment in vulnerable populations living in Shanghai. The probability-proportional-to-size sampling technique was used to select at least 360 pregnant women for urine iodine test and at least 1200 students for thyroid measurement and the household salt test. Of these students, at least 360 performed urine iodine test. The median thyroid volume and the median household salt iodine concentration of children aged 8-10 years were 1.80 ml and 24.8 mg/kg in 2015, and 0.97 ml and 28.3 mg/kg in 2011. The median urine iodine concentration (UIC) of pregnant women was 126.52 and 139.77 µg/L in 2015 and 2011. All differences were statistically significant (P < 0.05). The median UIC of students was 171.40 and 181.63 µg/L in 2015 and 2011, the difference was not statistically significant. Multivariate linear regression analysis showed that thyroid volume in children was associated with sex, age, region, and household salt iodized concentration. The current iodized salt concentration meets the basic needs of the population's iodine requirements except for pregnant women. Periodic monitoring is necessary particularly in vulnerable groups.


Asunto(s)
Yodo/orina , Estado Nutricional , Embarazo/orina , Adulto , Niño , China/epidemiología , Femenino , Humanos , Masculino , Análisis Multivariante , Sales (Química)/orina , Nódulo Tiroideo/diagnóstico
13.
Asia Pac J Public Health ; 29(4): 288-295, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28569114

RESUMEN

National iodine-deficiency disorder surveillance surveys were conducted in 1999, 2005, and 2011 in China. Probability-proportional-to-size sampling technique was used to select sampling units. The mean of thyroid volume (Tvol) in the 100 to 199 µg/L UIC (urinary iodine concentration) group was significantly lower than that in the 200 to 299 µg/L UIC group in 2011 ( P < .05). The status in the 100 to 199 µg/L versus ≥300 µg/L and 200 to 299 µg/L versus ≥300 µg/L groups in 1999, and 100 to 199 µg/L versus ≥300 µg/L group in 2011 were the same ( P < .05). The mean Tvol in the <100 µg/L UIC group was significantly higher than that in the 100 to 199 µg/L UIC group in 1999 ( P < .05). Both insufficient and excess iodine may be associated with an increase in Tvol, and adequate iodine intake should be defined as median UIC 100 to 299 µg/L.


Asunto(s)
Yodo/deficiencia , Yodo/orina , Vigilancia de la Población , Glándula Tiroides/crecimiento & desarrollo , Niño , China , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Tamaño de los Órganos
14.
Medicine (Baltimore) ; 96(16): e6663, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28422875

RESUMEN

OBJECTIVES: Invasive micropapillary carcinoma of the breast (IMPC) constitutes a unique and aggressive subtype of breast cancer. We aimed to evaluate the prognostic significance of the Jagged1 (a ligand of the Notch pathway) expression, and infiltration density of tumor-associated macrophages (TAMs) in patients with IMPC. METHODS: Jagged1 expression and CD163+, CD68+ macrophage infiltration were evaluated by immunohistochemistry in 222 tumor samples, and the clinical significance was analyzed. mRNA level of Jagged1 was analyzed by real time PCR in tumor tissues. RESULTS: The IMPC patients showed larger tumor size, more lymphatic invasion, higher expression levels of estrogen receptor (ER), increased Ki67 index, higher Jagged1 protein level, and denser infiltration of CD163+ macrophages compared to patients with invasive breast ductal carcinoma. In the IMPC cohort, positive Jagged1 expression was related to aggressive features including large tumor size, lymphatic invasion, and Ki67 overexpression. Statistical significance was found between CD163+ macrophage infiltration and Jagged1 expression levels. Cox regression analysis revealed that ER negativity, positive Jagged1 expression, and a high degree of CD163+ macrophage infiltration were independent prognostic factors for disease-free survival, and positive Jagged1 expression was an independent prognostic factor for overall survival. The level of Jagged1 mRNA was higher in tumor tissues of patients with IMPC. CONCLUSION: Jagged1, by modulating TAMs infiltration, is associated with a less favorable prognosis for patients with IMPC. Our results have important implications for therapies targeting Jagged1-Notch signaling and re-educating TAMs polarization for patients with IMPC.


Asunto(s)
Carcinoma Ductal de Mama/mortalidad , Carcinoma Ductal de Mama/patología , Proteína Jagged-1/biosíntesis , Macrófagos/metabolismo , Adulto , Anciano , Diferenciación Celular , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Metástasis Linfática , Persona de Mediana Edad , Pronóstico , ARN Mensajero , Receptores de Estrógenos/biosíntesis
15.
Br J Nutr ; 116(6): 1068-76, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27498626

RESUMEN

I deficiency is a worldwide public health problem. Median urinary I concentration in school-aged children has been used globally as a proxy for all populations. This study aims to determine whether median urinary I concentration of school-aged children is an appropriate indicator of I nutritional status in different adult populations. This is a secondary data analysis of two national I Deficiency Disorder surveys (2011, 2014) and two regional surveys (in coastal areas, 2009, and in high-risk areas, 2009-2014). Population groups included in these surveys were school-aged children (8-10 years), pregnant women, lactating women, women of childbearing age and adults (men and women, 18-45 years). All participants were self-reported healthy without history of thyroid diseases or were not using thyroid medicines. The median urinary I concentration of school-aged children was matched with that of the other population at the county level. The matched populations had similar iodised salt supply, food and water I, food composition and I content in salt. Weak or moderate correlation of median urinary I concentrations was observed between school-aged children and pregnant women and between children and lactating women. However, the agreement was stronger between children and women of childbearing age and between children and adult men and women. The results could be affected by cut-off values, data aggregation level and sample size. Using median urinary I concentration of school-aged children tends to overestimate that of pregnant women and lactating women. Median urinary I concentration of school-aged children can be used for assessing I nutrition in the adult population.


Asunto(s)
Yodo/deficiencia , Yodo/orina , Adolescente , Adulto , Niño , China , Femenino , Humanos , Lactancia , Masculino , Persona de Mediana Edad , Estado Nutricional , Embarazo , Factores de Riesgo , Adulto Joven
16.
PLoS One ; 11(6): e0157369, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27333072

RESUMEN

Nickel laterites cannot be effectively used in physical methods because of their poor crystallinity and fine grain size. Na2SO4 is the most efficient additive for grade enrichment and Ni recovery. However, how Na2SO4 affects the selective reduction of laterite ores has not been clearly investigated. This study investigated the decomposition of laterite with and without the addition of Na2SO4 in an argon atmosphere using thermogravimetry coupled with mass spectrometry (TG-MS). Approximately 25 mg of samples with 20 wt% Na2SO4 was pyrolyzed under a 100 ml/min Ar flow at a heating rate of 10°C/min from room temperature to 1300°C. The kinetic study was based on derivative thermogravimetric (DTG) curves. The evolution of the pyrolysis gas composition was detected by mass spectrometry, and the decomposition products were analyzed by X-ray diffraction (XRD). The decomposition behavior of laterite with the addition of Na2SO4 was similar to that of pure laterite below 800°C during the first three stages. However, in the fourth stage, the dolomite decomposed at 897°C, which is approximately 200°C lower than the decomposition of pure laterite. In the last stage, the laterite decomposed and emitted SO2 in the presence of Na2SO4 with an activation energy of 91.37 kJ/mol. The decomposition of laterite with and without the addition of Na2SO4 can be described by one first-order reaction. Moreover, the use of Na2SO4 as the modification agent can reduce the activation energy of laterite decomposition; thus, the reaction rate can be accelerated, and the reaction temperature can be markedly reduced.


Asunto(s)
Espectrometría de Masas/métodos , Minerales/química , Níquel/química , Sulfatos/química , Termogravimetría/métodos , Cinética , Microscopía Electrónica de Rastreo , Temperatura , Agua/química , Difracción de Rayos X
17.
PLoS One ; 11(2): e0148330, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26863208

RESUMEN

BACKGROUND: This study aimed to confirm whether strain ratio should be added after evaluation of lesions with 5-point elasticity scoring for differentiating benign and malignant breast lesions on ultrasonographic elastography(UE). MATERIALS AND METHODS: From June 2010 to March 2012, 1080 consecutive female patients with breast lesions were recruited into a multicenter retrospective study, which involved 8 centers across China. Each institutional ethic review board approved the study, and all the patients gave written informed consent. All the patients underwent the UE procedure and the strain ratios were calculated and the final diagnosis was made by histological findings. The sensitivity, specificity, accuracy, PPV and NPV were calculated for each of the two evaluation systems and the areas under the ROC curve were compared. RESULTS: The strain ratios of benign lesions (mean, 2.6±2.0) and malignant lesions (mean,7.9±5.8) were significantly different (p <0.01). When the cutoff point was 3.01, strain ratio method had 79.8% sensitivity, 82.8% specificity, and 81.3% accuracy, while the 5-point scoring method had 93.1% sensitivity, 73.0% specificity, and 76.8% accuracy. The areas under the ROC curve with the strain ratio method and 5-point scoring method were 0.863 and 0.865, respectively(p>0.05). The strain ratio method shows better a diagnosis performance of the lesions with elasticity score 3 and 4. CONCLUSIONS: Although the two UE methods have similar diagnostic performance, separate calculation of the strain ratios seems compulsory, especially for the large solid breast lesions and the lesions with elasticity score 3 and 4.


Asunto(s)
Adenocarcinoma/diagnóstico , Neoplasias de la Mama/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Diagnóstico por Imagen de Elasticidad/métodos , Ultrasonografía Mamaria/métodos , Adenocarcinoma/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Elasticidad , Diagnóstico por Imagen de Elasticidad/instrumentación , Femenino , Humanos , Glándulas Mamarias Humanas/patología , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos , Ultrasonografía Mamaria/instrumentación
18.
Eur J Radiol ; 84(12): 2492-500, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26349410

RESUMEN

OBJECTIVES: The purpose was to evaluate whether BI-RADS (the Breast Imaging Recording and Data System) combined with UE (ultrasound elastography) could improve the differentiation and characterization of benign and malignant breast lesions by comparing with BI-RADS. METHODS: A total of 1080 patients with 1194 breast lesions were studied retrospectively at 8 different institutions from 3 geographic areas across China (North, South, and West) from June 2010 to March 2012. Each institutional ethic review board approved the study and all patients gave written informed consent. All the cases were examined by conventional US (ultrasonography) and UE prior to ultrasound-guided core biopsy. Performance of BI-RADS and BI-RADS combined with UE were compared in different size groups, age groups and area groups. RESULTS: BI-RADS combined with UE cloud improve the accuracy by 13.2% compared to BI-RADS alone for all lesions, 23.2% for <10 mm lesions, 13.3% for ≥10-20 mm lesions, 6.3% for ≥20 mm lesions, 18.4% for <50 years group, 1.7% for ≥50 years group, 13.7% for northern area group, 17.7% for southern area group and 4.4% for western area group. CONCLUSIONS: The help which UE contributed to BI-RADS was greater for breast lesions <10mm and <50 years group.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Diagnóstico por Imagen de Elasticidad/métodos , Sistemas de Información Radiológica , Ultrasonografía Mamaria/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , China , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Adulto Joven
19.
Arch Iran Med ; 18(6): 386-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26058937

RESUMEN

A 30-day-old neonate was brought to our hospital due to testicular neoplasm in the right scrotum. Scrotal ultrasonography revealed a mixed cystic and solid mass in the testis. Analysis of testicular tumor markers was negative. Scrotal exploration was performed. A red nodular tumor was removed from the testis by surgery. Histological examination of the specimen showed it to be hemangiolymphangioma (HLA).


Asunto(s)
Hemangioma/diagnóstico , Linfangioma/diagnóstico , Escroto/diagnóstico por imagen , Neoplasias Testiculares/diagnóstico , Testículo/patología , Hemangioma/cirugía , Humanos , Recién Nacido , Linfangioma/cirugía , Masculino , Neoplasias Testiculares/cirugía , Ultrasonografía
20.
PLoS One ; 9(11): e111937, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25375854

RESUMEN

BACKGROUND: In spite of the salt iodization, iodine deficiency disorders (IDD) have not been sustainably eliminated in China. There are coastal areas with low iodized salt coverage rates (iodine nutrition is inadequate) and other areas with excessive amounts of iodine in the drinking water. OBJECTIVE: This study aimed to clarify the association of iodine deficiencies resulting from a low coverage rate of iodized salt, excess iodine intake from drinking water with thyroid function and disease in adults. DESIGN: A cross-sectional study was conducted in adults in different iodine nutrition areas in three provinces in China. RESULTS: The prevalence of thyroid nodules was 15.52%, 8.66% and 22.17% in the iodine excess, sufficient and deficient groups, respectively. The prevalence of subclinical hypothyroidism was 20.09%, 10.41%, and 2.25% in the excess, sufficient and deficient iodine groups, respectively. The prevalence of subclinical hyperthyroidism and overt hyperthyroidism in the iodine deficient group was higher than that in the iodine excess group ([Formula: see text] = 9.302, p = 0.002) and iodine sufficient group ([Formula: see text] = 7.553, p = 0.006). Thyroid-stimulating hormone (TSH) was significantly correlated with excess iodine intake (ß = 1.764,P = 0.001) and deficient iodine intake (ß = -1.219, P = 0.028). CONCLUSIONS: Thyroid nodules are more likely to be present in the iodine excess and deficient areas than in the iodine sufficient areas. Subclinical hyperthyroidism and overt hyperthyroidism are more likely to be prevalent in the iodine deficient areas than in the iodine excess or sufficient areas. Subclinical hypothyroidism is more likely to be prevalent in the high iodine intake areas than in the iodine deficient or sufficient areas. Median TSH may be deemed as an alternative indicator for monitoring the iodine nutrition status of the adult population in iodine excess and deficient areas.


Asunto(s)
Agua Potable/análisis , Yodo/deficiencia , Cloruro de Sodio Dietético/efectos adversos , Enfermedades de la Tiroides/epidemiología , Adulto , Anciano , China , Estudios Transversales , Femenino , Humanos , Hipertiroidismo/epidemiología , Hipotiroidismo/epidemiología , Masculino , Persona de Mediana Edad , Enfermedades de la Tiroides/patología , Nódulo Tiroideo/epidemiología , Tirotropina/sangre
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