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1.
ACS Nano ; 18(13): 9470-9485, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38506224

RESUMO

Piezoelectric poly(vinylidene fluoride) (PVDF) and its copolymer, poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)), have attracted considerable attention due to their potential in flexible, biocompatible energy harvesting and sensing devices. However, their limited piezoelectric performance hinders their widespread application. Inspired by the concept of morphotropic phase boundary (MPB) prevalent in high-performance piezoelectric ceramics, we successfully constructed MPB in the piezoelectric polymer P(VDF-TrFE) through size-dependent interface effects. We provided direct structural evidence using atomic force microscopy-infrared spectroscopy (AFM-IR) and significantly improved the piezoelectric performance of P(VDF-TrFE). The emergence of MPB is attributed to the interface effect induced by electrostatic interactions between ZnO fillers and the -CH2, -CF2, and -CHF groups in P(VDF-TrFE). This interaction drives a concomitant competition between the all-trans ß phase (normal ferroelectric) and the 3/1 helical phase (relaxor), resulting in enhanced piezoelectric responses in the transition region. By coupling the MPB effect with a porous structure, we developed a piezoelectric nanogenerator (PENG) that surpasses the electrical output limitation of current P(VDF-TrFE)-based PENGs. The fabricated PENG exhibits superior piezoelectric outputs (6.9 µW/cm2), impressive pressure sensitivity (2.3038 V/kPa), ultrafast response time (4.3 ms), and recovery time (46.4 ms)─notably, without the need for additional poling treatment. In practical applications, the constructed PENG can efficiently generate characteristic signals in response to various human movements and harvest biomechanical energy. This work offers insight into utilizing interface-induced MPB and proposes a simple, scalable approach for developing high-performance self-polarized piezoelectric polymer films for self-powered sensing systems toward human-machine interaction.

2.
J Pain Res ; 17: 677-685, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38375406

RESUMO

Purpose: The pericapsular nerve group (PENG) block provides satisfactory postoperative analgesia without hampering motor function for total hip arthroplasty (THA); however, unexpected motor block has been observed clinically. It is unknown whether this motor block is related to the dose of ropivacaine. We aimed to conduct a prospective randomized trial to test whether reducing the volume or concentration of ropivacaine was better for less motor block after PENG block. Patients and Methods: Ninety-nine patients with fracture or femoral head necrosis scheduled for THA were randomly allocated to receive 20 mL 0.5% ropivacaine (Group A), 20 mL 0.25% ropivacaine (Group B), and 10 mL 0.5% ropivacaine (Group C). The primary outcome was the incidence of postoperative quadriceps motor block at 6 hours. Secondary outcomes were the incidence of postoperative quadriceps motor block at 0, 12, 24 and 48 hours; pain scores on the numeric rating scale (NRS) at all postoperative time points (0, 6, 12, 24, and 48 hours); the time to first walk; the incidence of rescue analgesia; side effects such as dizziness, ache, nausea, and vomiting; and patient satisfaction. Results: Compared with Group A, Group C resulted in a lower incidence of quadriceps motor block at 0 hours, 6 hours and 12 hours postoperatively (P < 0.05), while Group B only resulted in a lower incidence of motor block at 12 hours postoperatively (P < 0.05). No intergroup differences were found in terms of postoperative pain scores, the incidence of rescue analgesia, adverse events or patient satisfaction (P > 0.05). Conclusion: A higher incidence of motor blockade was observed when 20 mL of 0.5% ropivacaine was administered, which was mainly caused by the excessive volume. Therefore, we recommend performing PENG block with 10 mL 0.5% ropivacaine.

3.
Zookeys ; 1190: 195-212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38323097

RESUMO

Taxonomic notes on the Talaus species from China are provided. Two new species, T.yuyang Yao & Liu, sp. nov. and T.zhangjiangkou Yao & Liu, sp. nov. are described and illustrated, and a further three species are redescribed based on their genitalic characters: T.dulongjiang Tang, Yin, Ubick & Peng, 2008, T.niger Tang, Yin, Ubick & Peng, 2008, and T.sulcus Tang & Li, 2010. The species T.xiphosus Zhu & Ono, 2007 is considered a junior synonym of T.triangulifer Simon, 1886 based on an examination of many recently collected female and male specimens from Guangxi Province, China. Diagnoses, detailed illustrations and a map of distributional records of the six treated species of Talaus in China are provided.

4.
Mater Horiz ; 11(4): 995-1007, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38047955

RESUMO

Transcutaneous energy-harvesting technology based on ultrasound-driven piezoelectric nanogenerators is the most promising technology in medical and industrial applications. Based on ultrasonic coupling effects at the interfaces, the interfacial architecture is a critical parameter to attain desirable electromechanical properties of nanocomposites. Herein, we successfully synthesized core-conductive shell-structured BaTiO3@Carbon [BT@Carbon] nanoparticles [NPs] as nanofillers to design implantable poly(vinylidenefluoride-co-chlorotrifluoroethylene)/BT@Carbon [P(VDF-CTFE)/BT@Carbon] piezoelectric nanogenerators (PENGs) and actuators for harvesting ultrasound (US) underneath the skin. For US-driven PENGs, the electrons and holes are generated not only from the interfaces between the BT@Carbon NPs and the matrix, but also from the dipoles vibrating in the smaller lamellae of ferroelectric ß-phase crystals in poled nanocomposites. Remarkably, P(VDF-CTFE)/BT@Carbon piezoelectric nanogenerators could attain an extraordinary output power of 521 µW cm-2 under ultrasound stimulation, which is far greater than that of force-induced PVDF-based nanogenerators and other ultrasound-driven triboelectric generators. Furthermore, the US-PENG actuator system, which is composed of an amplifier and a microcontroller, could efficiently convert ultrasonic energy into electricity or instructions to switch on/off small electronics in the tissues and organs of mice. Finally, the nanocomposite-based US-driven PENGs have a good biocompatibility, with no cytotoxicity or immune response in vivo, indicating their potential for developing wireless power generators and actuators for medical implant devices.

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1005106

RESUMO

This paper summarized PENG Qinghua's clinical experience in treating dry eye by applying therapeutic method of maintaining with sweet medicinals and restoring the body fluids. It is believed that the spleen earth insufficiency and fluids damage transforming into dryness are the main pathogenesis of the disease, and the basic therapeutic principle is maintaining with the sweet and restoring the body fluids by mainly using sweet medicines. It is advocated to use mild-sweet herbs, such as Baibiandou (Lablab purpureus subsp. purpureus), Fuling (Smilax glabra Roxb.), and Yiyiren (Coix lacryma-jobi L.), to transport spleen earth, so that qi is restored and body fluids are recovered; moderate-sweet herbs, such as Dangshen (Codonopsis pilosula [Franch.] Nannf.), Taizishen (Pseudostellaria heterophylla [Miq.] Pax), Shanyao (Dioscorea oppositifolia L.) and Zhigancao (Glycyrrhiza glabra L.) are suggested to cultivate earth and generate metal, so as to move qi and circulate fluid; sweet-cool herbs, such as Nanshashen (Adenophora triphylla [Thunb.] A.DC.), Beishashen (Glehnia littoralis [A.Gray] F.Schmidt ex Miq.), Yuzhu (Polygonatum odoratum [Mill.] Druce), Tianhuafen (Trichosanthes kirilowii Maxim.) are suggested to nourish yin and increase body fluids, so as to promote fluid production to moisten dryness. In this way, when the source of fluid is restored and the fluid is circulated, the fluid can be produced continuously, which provides new ideas for the treatment of dry eyes with traditional Chinese medicine.

6.
Small ; 19(48): e2304599, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37544920

RESUMO

Considerable thermal energy is emitted into the environment from human activities and equipment operation in the course of daily production. Accordingly, the use of thermoelectric generators (TEGs) can attract wide interest, and it shows high potential in reducing energy waste and increasing energy recovery rates. Notably, TEGs have aroused rising attention and been significantly boosted over the past few years, as the energy crisis has worsened. The reason for their progress is that thermoelectric generators can be easily attached to the surface of a heat source, converting heat energy directly into electricity in a stable and continuous manner. In this review, applications in wearable devices, and everyday life are reviewed according to the type of structure of TEGs. Meanwhile, the latest progress of TEGs' hybridization with triboelectric nanogenerator (TENG), piezoelectric nanogenerator (PENG), and photovoltaic effect is introduced. Moreover, prospects and suggestions for subsequent research work are proposed. This review suggests that hybridization of energy harvesting, and flexible high-temperature thermoelectric generators are the future trends.

7.
Insects ; 14(4)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37103180

RESUMO

Spiders of the genus Pholcus were collected for the first time during an expedition to the Lüliang Mountains in Shanxi Province, North China. Phylogenetic analyses of DNA sequence data from COI, H3, wnt, and 28S genes allowed us to group them into nine well-supported clades. We used morphology and four methods of molecular species delimitation, namely Automatic Barcode Gap Discovery (ABGD), the Generalized Mixed Yule Coalescent (GMYC), Bayesian Poisson Tree Processes (bPTP), and Bayesian Phylogenetics and Phylogeography (BPP), to investigate species boundaries. These integrative taxonomic analyses identified the nine clades as nine distinct species, comprising Pholcus luya Peng & Zhang, 2013 and eight other species new to science: Pholcus jiaocheng sp. nov., Pholcus linfen sp. nov., Pholcus lishi sp. nov., Pholcus luliang sp. nov., Pholcus wenshui sp. nov., Pholcus xiangfen sp. nov., Pholcus xuanzhong sp. nov., and Pholcus zhongyang sp. nov. The species occur in geographic proximity and show many morphological similarities. All of them belong to the P. phungiformes species group. The records from the Lüliang Mountains represent the westernmost distribution limit of this species group.

8.
Med Sci Monit ; 29: e939599, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36718656

RESUMO

This publication has been retracted by the Editor due to non-original content and deficiencies in the conduct of the study. Reference: Jia-Yuan Zhuang, Zhi-Yao Chen, Tao Zhang, Du-Peng Tang, Xiao-Yin Jiang, Ze-Hao Zhuang. Effects of Different Ratio of n-6/n-3 Polyunsaturated Fatty Acids on the PI3K/Akt Pathway in Rats with Reflux Esophagitis. Med Sci Monit, 2017; 23: 542-547. DOI: 10.12659/MSM.898131.

9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1003831

RESUMO

This paper summarized clinical experience of Professor Peng Qinghua in the staged treatment of autoimmune uveitis (AU). The pathogenesis of AU is always based on root-cause deficiency and manifestation excess, with weakness of healthy qi as the root, and accumulation of wind, dampness and blood stasis as the minifestation. Syndrome differentiation and treatment is usually carried out according to different stages of disease. During the acute stage, deficiency of healthy qi and stagnation of wind-dampness are the key pathomechanisms, so the treatment is to replenish qi and activate blood, dispel wind and remove dampness, and self-made Yiqi Huoxue Qufeng Chushi Decoction (益气活血祛风除湿方) can be used. During remission stage, deficiency of spleen and kidney is the key mechanism, so the treatment is to tonify the spleen and kidney, replenish the essence and brighten the eyes, and self-made Yijing Mingmu Decoction (益精明目汤) can be used. Meanwhile, it was recommened to treat early, prevent and interrupt the disease, commonly combine with Chinese patent medicine Zhengqing Fengtongning tablets (正清风痛宁缓释片), and promote regulation of living to prevent recurrence.

10.
J Chem Theory Comput ; 18(3): 1569-1583, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35138865

RESUMO

We present an accurate computational approach to calculate absolute K-edge core electron excitation energies as measured by X-ray absorption spectroscopy. Our approach employs an all-electron Bethe-Salpeter equation (BSE) formalism based on GW quasiparticle energies (BSE@GW) using numeric atom-centered orbitals (NAOs). The BSE@GW method has become an increasingly popular method for the computation of neutral valence excitation energies of molecules. However, it was so far not applied to molecular K-edge excitation energies. We discuss the influence of different numerical approximations on the BSE@GW calculation and employ in our final setup (i) exact numeric algorithms for the frequency integration of the GW self-energy, (ii) G0W0 and BSE starting points with ∼50% of exact exchange, (iii) the Tamm-Dancoff approximation and (iv) relativistic corrections. We study the basis set dependence and convergence with common Gaussian-type orbital and NAO basis sets. We identify the importance of additional spatially confined basis functions as well as of diffuse augmenting basis functions. The accuracy of our BSE@GW method is assessed for a benchmark set of small organic molecules, previously used for benchmarking the equation-of-motion coupled cluster method [Peng et al., J. Chem. Theory Comput., 2015, 11, 4146], as well as the medium-sized dibenzothiophene (DBT) molecule. Our BSE@GW results for absolute excitation energies are in excellent agreement with the experiment, with a mean average error of only 0.63 eV for the benchmark set and with errors <1 eV for the DBT molecule.

11.
ACS Omega ; 7(6): 5332-5339, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35187348

RESUMO

The alpha function is an important part of the attractive term of cubic equation of state (EoS), which affected the predictive accuracy of thermodynamic properties. In this paper, four new alpha functions (Alpha Function-1 to Alpha Function-4) were proposed for the Peng-Robinson (PR) EoS. The proposed alpha functions and their derivatives satisfied the requirements of the thermodynamic consistency test. The four alpha functions with PR EoS were used to predict the thermodynamic properties of 11 kinds of compounds, the average relative deviation (ARD) of Alpha Function-1 and Alpha Function-2 for the prediction of vapor pressures was 0.57%, and the ARDs of Alpha Function-3 and Alpha Function-4 were 0.44 and 0.38%, respectively. The ARDs of Alpha Function-4 for the estimation of enthalpy of vaporization, liquid volume, and liquid isobaric heat capacity of seven kinds of compounds were 1.46, 7.54, and 7.59%, respectively. The proposed three-parameter alpha functions were more accurate than the two-parameter function for the prediction the vapor pressure and enthalpy of vaporization of pure compounds. However, any alpha function used in the attractive term of PR EoS had great deviations for the estimation of liquid volume and isobaric heat capacity.

12.
Journal of Chinese Physician ; (12): 823-827,832, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-956224

RESUMO

Objective:To investigate the analgesic effect of ultrasound-guided pericapsular nerve group (PENG) block combined with laryngeal mask general anesthesia and internal fixation of proximal femoral nail antirotation (PFNA) under ERAS concept in elderly patients.Methods:A total of 50 elderly patients with femoral trochanteric fractures treated with PFNA internal fixation who were admitted to Changsha Central Hospital from January 2021 to March 2022 were selected and according to the random number table method, they were divided into groups P and F, with 26 cases in group P (ultrasound-guided PENG block combined with laryngeal mask general anesthesia group) and 24 cases in group F [ultrasound-guided fascia iliaca compartment block (FICB)] combined with laryngeal mask general anesthesia group]. The bispectral index (BIS) of the two groups of patients was maintained within the range of 40-60, and the dosage of cyclopofol and remifentanil was adjusted according to the BIS and hemodynamic changes. Postoperative oxycodone was used for patient controlled intravenous analgesia (PCIA). When the Visual Analogue Scale (VAS) score ≥4, 1 mg intravenous oxycodone was administered as rescue analgesia. The VAS score was observed and recorded before nerve block (T 0), 10 minutes after nerve block (T 1), 20 minutes after nerve block (T 2), when the patients were placed in body position after bed (T 3), after laryngeal mask removal (T 4), 12 h after operation (T 5), 24 h after operation (T 6) and 48 h after operation (T 7). The mean arterial pressure (MAP), heart rate (HR) and blood oxygen saturation (SpO 2) at each time point from T 0 to T 4 were observed and recorded; the intraoperative dose of remifentanil, the rescue dose of oxycodone at postoperative T 6 and T 7, Lovett muscle strength score, anesthesia operation time, anesthesia recovery time and postoperative anesthesia-related complications were recorded. Results:There was no significant difference between the two groups in VAS scores at T 0, T 4, T 5 and T 6, MAP, HR and SpO 2 at T 0, T 1, T 2 and T 4, the dosage of remifentanil during operation, the remedial dosage of oxycodone at T 6 after operation, anesthesia operation time and anesthesia recovery time (all P>0.05). Compared with group F, the VAS scores of group P at T 1, T 2, T 3 and T 7 were lower than those of group F (all P<0.05); At T 3, there was no significant difference in SpO 2 between the two groups ( P>0.05), but the MAP and HR in group P was lower than that in group F (all P<0.05); The remedial dose of oxycodone at T 7 in group P was lower than that in group F ( P<0.05), and the analgesic effect was longer; Lovett muscle strength score at T 6 and T 7 in group P was better than that in group F (all P<0.05). There was no significant difference in the incidence of postoperative complications between the two groups ( P>0.05). Conclusions:Compared with FICB, ultrasound-guided PENG block used in PFNA internal fixation in elderly patients has faster effect, lower dosage of opioid analgesics, longer duration of analgesia, and less impact on postoperative lower limb muscle strength.

13.
Entropy (Basel) ; 22(9)2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-33286779

RESUMO

A high-pressure pneumatic catapult works under extreme boundaries such as high-pressure and rapid change of pressure and temperature, with the features of nonlinearity and gas-solid convection. In the thermodynamics processes, the pressure is much larger than the critical pressure, and the compressibility factor can deviate from the Zeno line significantly. Therefore, the pneumatic performance and thermo-physical properties need to be described with the real gas hypothesis instead of the ideal gas one. It is found that the analytical results based on the ideal gas model overestimate the performance of the catapult, in comparison to the test data. To obtain a theoretical model with dynamic leakage compensation, leakage tests are carried out, and the relationship among the leakage rate, pressure and stroke is fitted. The compressibility factor library of the equation of state for compressed air is established and evaluated by referring it to the Nelson-Obert generalized compressibility charts. Based on the Peng-Robinson equation, a theoretical model of the high-pressure pneumatic catapult is developed, in which the effects of dynamic leakage and the forced convective heat transfer between the gas and the metal wall are taken into account. The results from the theoretical model are consistent with the data from ejection tests. This research presents an approach to study the performance of a high-pressure pneumatic catapult with high precision.

14.
PhytoKeys ; 162: 29-36, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117069

RESUMO

A new species of Begonia section Coelocentrum, B. guangdongensis W.H. Tu, B.M. Wang & Y.L. Li from Guangdong Province, China, is described and illustrated here. Morphologically, the new species is most similar to B. biflora T. C. Ku and B. longistyla Y. M. Shui & W. H. Chen, but differs from B. biflora by its rugose leaves and glabrous capsules and from B. longistyla by its glabrous stipules without ciliate margin, densely hirsute-pilose leaves and obtuse apex of bracts. Additionally, it is also somewhat similar to B. chongzuoensis Yan Liu, S. M. Ku & C.-I Peng, but there are significant distinctions in their stipules, leaves and bracts. The conservation status of B. guangdongensis is assessed as Critically Endangered (CR), according to the IUCN Red List Categories and Criteria.

15.
FASEB J ; 33(1): 163-174, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29969578

RESUMO

A key member of the sentrin/small ubiquitin-like modifier (SUMO)-specific protease (SENP) family, SENP2 has been shown to implicate embryonic development, fatty acid metabolism, atherosclerosis, and neurodegenerative diseases. However, other biologic functions of SENP2 and its specific targets are incompletely understood. Here, we uncovered a novel role of SENP2 in negative regulation of keratinocyte migration, a process crucial to wound epithelialization. Defects in this function are often associated with the clinical phenotypes of chronic nonhealing wounds. Mechanistically, SENP2 as a specific de-SUMOylase targets NDR1 (nuclear Dbf2-related 1), also called STK38 (serine-threonine kinase 38), for de-SUMOylation and SUMO conjugation of NDR1 on Lys-465 attenuates its inhibition of p38/ERK1/2 activation by decreasing the association of NDR1 with MEK kinase 1/2. Significantly, low-level laser (LLL) irradiation increases NDR1 SUMOylation and subsequent p38/ERK1/2 activation via down-regulation of SENP2, leading to faster keratinocyte migration. Our findings fill the gaps that linger in the basic mechanisms underlying LLL therapy.-Xiao, N., Li, H., Yu, W., Gu, C., Fang, H., Peng, Y., Mao, H., Fang, Y., Ni, W., Yao, M. SUMO-specific protease 2 (SENP2) suppresses keratinocyte migration by targeting NDR1 for de-SUMOylation.


Assuntos
Movimento Celular , Cisteína Endopeptidases/metabolismo , Queratinócitos/fisiologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Sumoilação , Ubiquitina/metabolismo , Células Cultivadas , Regulação para Baixo , Humanos , Queratinócitos/citologia , Proteínas Serina-Treonina Quinases/metabolismo
16.
FASEB J ; 32(2): 576-587, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28935820

RESUMO

Serum- and glucocorticoid-inducible kinase 3 (SGK3) is a downstream mediator of PI3K, which is essential for maintaining the functional integrity of podocytes. However, little is known about the role of SGK3 in podocyte function. Herein, we demonstrated that SGK3 contributes to the maintenance of podocyte integrity. Conditionally immortalized mouse podocyte cells (MPCs) were treated with puromycin aminonucleoside (PAN). PAN treatment inhibited the activity of SGK3 and the expression of podocin. Short hairpin RNA (shRNA)-mediated knockdown of SGK3 also reduced podocin expression in the absence of PAN. Adriamycin (ADR)-treated mice developed proteinuria and had decreased renal glomerular SGK3 expression in comparison to control mice. Consistent with a role for SGK3 in the ADR effect, SGK3 knockout (KO) mice had markedly reduced kidney podocin expression and significantly elevated proteinuria compared with wild-type mice. Electron microscopy revealed that SGK3 KO mice displayed partial effacement of podocyte foot processes. Further, a SGK3 target protein, glycogen synthase kinase-3 (GSK3), was discovered to be dramatically activated in PAN and SGK3 shRNA-treated MPCs and in SGK3 KO mice. Taken together, these data strongly suggest that SGK3 plays a significant role in regulating podocyte function, likely by controlling the expression and activity of GSK3.-Peng, L.-Q., Zhao, H., Liu, S., Yuan, Y.-P., Yuan, C.-Y., Mwamunyi, M.-J., Pearce, D., Yao, L.-J. Lack of serum- and glucocorticoid-inducible kinase 3 leads to podocyte dysfunction.


Assuntos
Podócitos/enzimologia , Proteínas Serina-Treonina Quinases/deficiência , Animais , Linhagem Celular Transformada , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Podócitos/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Puromicina Aminonucleosídeo/efeitos adversos , Puromicina Aminonucleosídeo/farmacologia
17.
Environ Health Perspect ; 124(1): 164-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26009470

RESUMO

BACKGROUND: Thallium (Tl) is a highly toxic heavy metal widely present in the environment. Case reports have suggested that maternal exposure to high levels of Tl during pregnancy is associated with low birth weight (LBW), but epidemiological data are limited. OBJECTIVES: This study was designed to evaluate whether prenatal Tl exposure is associated with an increased risk of LBW. METHODS: This case-control study involving 816 study participants (204 LBW cases and 612 matched controls) was conducted in Hubei Province, China, in 2012-2014. Tl concentrations were measured in maternal urine collected at delivery, and associations with LBW were evaluated using conditional logistic regression. RESULTS: Higher maternal urinary Tl levels were significantly associated with increased risk of LBW [crude odds ratio (OR) = 1.52; 95% CI: 1.00, 2.30 for the highest vs. lowest tertile], and the association was similarly elevated after adjustment for potential confounders (adjusted OR = 1.90; 95% CI: 1.01, 3.58 for the highest vs. lowest tertile). Stratified analyses showed slightly higher risk estimates for LBW associated with higher Tl levels for mothers < 28 years old and for mothers with lower household income; however, there was no statistical evidence of heterogeneity in risk according to maternal age (p for heterogeneity = 0.18) or household income (p for heterogeneity = 0.28). CONCLUSION: To our knowledge, ours is the first case-control study to investigate the association between prenatal Tl exposure and LBW. The results suggest that prenatal exposure to high levels of Tl may be associated with an increased risk of LBW. CITATION: Xia W, Du X, Zheng T, Zhang B, Li Y, Bassig BA, Zhou A, Wang Y, Xiong C, Li Z, Yao Y, Hu J, Zhou Y, Liu J, Xue W, Ma Y, Pan X, Peng Y, Xu S. 2016. A case-control study of prenatal thallium exposure and low birth weight in China. Environ Health Perspect 124:164-169; http://dx.doi.org/10.1289/ehp.1409202.


Assuntos
Recém-Nascido de Baixo Peso/fisiologia , Tálio/toxicidade , Estudos de Casos e Controles , China , Feminino , Humanos , Recém-Nascido , Modelos Logísticos , Exposição Materna/efeitos adversos , Gravidez
18.
J Phys Chem B ; 110(26): 13195-202, 2006 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-16805632

RESUMO

We present complementary molecular simulations and experimental results of phase equilibria for carbon dioxide expanded acetonitrile, methanol, ethanol, acetone, acetic acid, toluene, and 1-octene. The volume expansion measurements were done using a high-pressure Jerguson view cell. Molecular simulations were performed using the Gibbs ensemble Monte Carlo method. Calculations in the canonical ensemble (NVT) were performed to determine the coexistence curve of the pure solvent systems. Binary mixtures were simulated in the isobaric-isothermal distribution (NPT). Predictions of vapor-liquid equilibria of the pure components agree well with experimental data. The simulations accurately reproduced experimental data on saturated liquid and vapor densities for carbon dioxide, methanol, ethanol, acetone, acetic acid, toluene, and 1-octene. In all carbon dioxide expanded liquids (CXL's) studied, the molecular simulation results for the volume expansion of these binary mixtures were found to be as good as, and in many cases superior to, predictions based on the Peng-Robinson equation of state, demonstrating the utility of molecular simulation in the prediction of CXL phase equilibria.


Assuntos
Dióxido de Carbono/química , Solventes/química , Método de Monte Carlo
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