Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 36
Filtrar
1.
Angew Chem Int Ed Engl ; 63(4): e202316194, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38009443

RESUMO

Borate crystals can be chemically and functionally modified by the fluorination strategy, which encourages the identification of emerging fluorooxoborates with a structure and set of characteristics not seen in any other oxide parents. However, the bulk of fluorooxoborates have been found accidentally, rational methods of synthesis are required, particularly for the infrequently occurring poly-fluorinated components. Herein, we reported the use of bifluoride salts as a potent source of fluorine to prepare fluorooxoborates that contain rarely tri-fluorinated [BF3 X] (X=O and CH3 ) tetrahedra and eleven compounds were found. We identified the optical properties of the organofluorinated group [CH3 BF3 ] and their potential for nonlinear optics for the first time. Among these, two non-centrosymmetric components hold potential for the production of 266 nm harmonic coherent light for nonlinear optics, and more crucially, have the benefit of growing large size single crystals. Our study establishes experimental conditions for the coexistence of the diverse functional groups, enabling the production of poly-fluorinated optical crystals.

2.
Angew Chem Int Ed Engl ; 62(42): e202310835, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37610762

RESUMO

Second-harmonic generation (SHG) is a fundamental optical property of nonlinear optical (NLO) crystals. Thus far, it has proved difficult to engineer large SHG responses, particularly in the mid-infrared region, owing to the difficulty in simultaneously controlling the arrangement and density of functional NLO-active units. Herein, a new assembly strategy employing functional modules only, and aimed at maximizing the density and optimizing the spatial arrangement of highly efficient functional modules, has been applied to the preparation of NLO crystals, affording the van der Waals crystal MoO2 Cl2 . This exhibits the strongest powder SHG response (2.1×KTiOPO4 (KTP) @ 2100 nm) for a transition-metal oxyhalide, a wide optical transparency window, and a sufficient birefringence. MoO2 Cl2 is the first SHG-active transition-metal oxyhalide effective in the infrared region. Theoretical studies and crystal structure analysis suggest that the densely packed, optimally-aligned [MoO4 Cl2 ] modules within the two-dimensional van der Waals layers are responsible for the giant SHG response.

3.
Zygote ; 31(4): 350-358, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37183670

RESUMO

This study aimed to screen factors related to live birth outcomes of women with first frozen embryo transfer (FET). The enrolled women were divided into training and validation cohorts. The least absolute shrinkage and selection operator (Lasso) regression algorithm of machine learning and the multiple regression model were then used to screen factors relevant to live birth failure (LBF) for the training dataset. A nomogram risk prediction model was established on the basis of the screened factors, and the consistency index (C-index) and calibration curve were derived for evaluating the model. The validation cohort was utilized to validate the nomogram model further. In total, 2083 women who accepted the first FET in our hospital were included and 44 factors were initially screened in this study. On the basis of the training cohort, the screened risk factors via multiple regression analysis with odds ratio (OR) values were female age (OR: 3.092, 95%CI: 1.065-4.852), body mass index (BMI; OR: 1.106, 95%CI: 1.015-1.546), caesarean section (OR: 1.909, 95%CI: 1.318-2.814), number of high-quality embryos (OR: 0.698, 95%CI: 0.599-0.812), and endometrial thickness (OR: 0.957, CI: 0.904-0.980). The nomogram model was generated based on five predictors. Furthermore, favourable results with C-indexes and calibration curves close to ideal curves indicated the accurate predictive ability of the nomogram. Female age, BMI, caesarean section, number of high-quality embryos, and endometrial thickness were independent predictors for LBF. The five factors of the risk assessment model may help to identify LBF with high accuracy in women who accept FET.


Assuntos
Cesárea , Nascido Vivo , Gravidez , Humanos , Feminino , Masculino , Estudos Retrospectivos , Taxa de Gravidez , Transferência Embrionária/métodos
4.
Inorg Chem ; 62(23): 9209-9216, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37257153

RESUMO

Borates provide an excellent platform for investigating the optical nonlinearity and linearity of crystals as photoelectric functional materials. In our work, borate derivatives with isolated [B3O3] six-membered rings as structural features are the preferred system due to their simple functional units and excellent properties. Herein, by utilizing the target-oriented synthesis, a series of borate derivatives, A2[B3O3F4(OH)] (A= NH4, Rb, Cs) (ABOFH), K2.3Cs0.7B3O3F6 (KCsBOF), and Cs3[B3O3(OH)3]Cl3 (CsBOHCl), with novel heteroanionic groups containing [BOxF4-x] (x = 0-3) and/or [BO2(OH)] units were obtained. ABOFH, KCsBOF, and CsBOHCl construct different two-dimensional pesudolayers featuring [B3O3F4(OH)], [B3O3F6], and [B3O3(OH)3] units, respectively. Also, the optical properties and the arrangement information of these anionic groups were studied. Among the total five compounds, (NH4)2[B3O3F4(OH)] and Cs3[B3O3(OH)3]Cl3 with enlarged birefringence and sufficient band gaps were screened out as promising birefringent crystals due to the optimally aligned configuration of birefringence-active heteroanionic units. The successful results of target-oriented synthesis indicate a more profound conclusion that the borate system now has more diversified structural chemistry, and an effective strategy was proposed to modify the arrangement and species of anionic units to optimize the performance of optical crystals.

5.
Langmuir ; 39(17): 6240-6248, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37083475

RESUMO

In this work, an urchin-like Ni@Ni2P@NiCoP (Ni@NP@NCP) composite was prepared on nickel foam by a simple hydrothermal treatment process. Using the prepared NiO nanosheets as templates, the NiCo precursor was prepared in the presence of three solvothermal systems of water/dimethylformamide (DMF)/dimethyl sulfoxide (DMSO) by the hydrothermal process. After mixing and calcining with sodium hypophosphite under a nitrogen atmosphere at a high temperature for phosphating, an urchin-like Ni@NP@NCP(F/SO/H) nanostructured catalyst was obtained with superior hydrogen evolution and oxygen evolution performance. To further explore their efficiency in seawater splitting. Ni@NP@NCP(F/SO/H) composites were used as the cathode and anode of an electrolytic cell, which delivered 1.822 V potential at 300 mA cm-2 in simulated seawater (1 M KOH and 0.5 M NaCl). This may provide an effective way of developing clean energy.

6.
mSphere ; 8(3): e0009623, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37017519

RESUMO

A balanced vaginal microbiome dominated by Lactobacillus can help promote women's reproductive health, with Lactobacillus crispatus showing the most beneficial effect. However, the potential role of vaginal microbiomes in hypertensive disorders of pregnancy (HDP) development is not thoroughly explored. In this nested case-control study based on an assisted reproductive technology follow-up cohort, we prospectively assessed the association between pregestational vaginal microbiomes with HDP by collecting vaginal swabs from 75 HDP cases (HDP group) and 150 controls (NP group) and using 16S amplicon sequencing for bacterial identification. The vaginal microbial composition of the HDP group significantly differed from that of the NP group. The abundance of L. crispatus was significantly lower, and the abundances of Gardnerella vaginalis was significantly higher, in the HDP group than in the NP group. Of note, L. crispatus-dominated vaginal community state type was associated with a decreased risk for HDP (odds ratio = 0.436; 95% confidence interval, 0.229 to 0.831) compared with others. Additionally, network analysis revealed different bacterial interactions with 61 and 57 exclusive edges in the NP and HDP groups, respectively. Compared with the HDP group, the NP group showed a higher weighted degree and closeness centrality. Several taxa, including G. vaginalis, L. iners, and bacterial vaginosis-associated bacteria (Prevotella, Megasphaera, Finegoldia, and Porphyromonas), were identified as "drivers" for network rewiring. Notable alterations of predicted pathways involved in amino acid, cofactor, and vitamin metabolism; membrane transport; and bacterial toxins were observed in the HDP group. IMPORTANCE The etiology of HDP remains unclear to date. Effective methods for the individualized prediction and prevention are lacking. Pregestational vaginal dysbiosis precedes the diagnosis of HDP, providing a novel perspective on the etiology of HDP. Early pregnancy is the critical period of placental development, and abnormal placentation initiates HDP development. Thus, disease prevention should be considered before pregnancy. Vaginal microbiome characterization and probiotic interventions before pregnancy are preferred because of their safety and potential for early prevention. This study is the first to prospectively assess associations between pregestational vaginal microbiome and HDP. L. crispatus-dominated vaginal community state type is linked to a reduced risk for HDP. These findings suggest that vaginal microbiome characterization may help identify individuals at high risk for HDP and offer potential targets for the development of novel pregestational intervention methods.


Assuntos
Disbiose , Hipertensão Induzida pela Gravidez , Feminino , Gravidez , Humanos , Estudos de Casos e Controles , Placenta , Vagina/microbiologia
7.
Reprod Biomed Online ; 46(6): 1005-1016, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37085428

RESUMO

RESEARCH QUESTION: What are the different features of the vaginal microbiome (VMB) between patients with polycystic ovary syndrome (PCOS) and healthy women? DESIGN: A cross-sectional study was conducted at a single academic university-affiliated centre. A total of 1446 participants were recruited (PCOS group, n =713, control group, n = 733). Vaginal swabs were analysed using 16S rRNA gene sequencing. The diversity and composition of the microbiome were compared between the PCOS group and the control group. Microbial interaction networks and functional prediction were investigated. RESULTS: The PCOS group had a higher alpha diversity than the control group (Shannon P = 0.03, Simpson P = 0.02), and higher intra-group variability was observed in PCOS group (P < 2.2E-16). At the genus level, the proportion of Lactobacillus decreased (85.1% versus 89.3%, false discovery rate [FDR] = 0.02), whereas the proportion of Gardnerella vaginalis and Ureaplasma increased in the PCOS group (5.1% versus 3.3%, FDR = 0.006; 1.2% versus 0.6%, FDR = 0.002, respectively). Lactobacillus acidophilus, Prevotella buccalis and G. vaginalis were identified as the main differential species. L. acidophilus was positively correlated with serum levels of anti-Müllerian hormone (AMH), and triglyceride (P = 2.01E-05, P = 0.004, respectively). P. buccalis was negatively correlated with serum levels of AMH and testosterone (P = 0.002, P = 0.003, respectively). G. vaginalis was positively correlated with serum levels of AMH, oestradiol and progesterone (P = 0.004, P = 0.005, P = 0.03, respectively). The VMB interaction network indicated that Lactobacillus crispus, Prevotella timonensis, and P. buccalis could be key drivers in the PCOS group. Overall, 55 predicted genes were found to be differentially abundant between PCOS and the control (FDRs < 0.25). CONCLUSIONS: The PCOS group had a higher diversity of vaginal microbiome and showed an enhanced level of heterogeneity. The proportion of Lactobacillus in the PCOS group decreased, whereas the proportions of Gardnerella and Ureaplasma increased. These results warrant further research that can validate the correlation between PCOS and VMB.


Assuntos
Microbiota , Síndrome do Ovário Policístico , Feminino , Humanos , Estudos Transversais , RNA Ribossômico 16S/genética , Hormônio Antimülleriano
8.
Reprod Biomed Online ; 46(3): 527-535, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36604214

RESUMO

RESEARCH QUESTION: Does follicular stimulation using human menopausal gonadotrophin (HMG) after pituitary down-regulation by a GnRH agonist improve endometrial thickness (EMT) and clinical outcomes of frozen-thawed embryo transfer (FET; using vitrified-warmed embryos) in women with thin endometrium after intensified oestrogen administration (IOA)? DESIGN: This was a retrospective study. A total of 627 patients attempted 683 FET cycles with at least one previous history of thin endometrium. None of the cycles reached over 7 mm EMT after using oral and vaginal oestradiol for more than 21 days (IOA protocol). A total of 129 cycles proceeded with FET, 305 cycles were cancelled, and 249 cycles involved administration of HMG following GnRH agonist pituitary down-regulation (GnRH agonist + HMG protocol) for further endometrial preparation. RESULTS: EMT became significantly greater (7.18 ± 1.14 mm versus 6.13 ± 0.63 mm, P < 0.001) using GnRH agonist + HMG compared with previous IOA cycles, but this was not related to serum oestrogen concentrations. A total of 213 cycles after the GnRH agonist + HMG protocol proceeded with FET, showing a significantly increased clinical pregnancy rate, implantation rate and live birth rate compared with those after IOA. CONCLUSIONS: The GnRH agonist + HMG protocol for endometrial preparation in FET cycles improves EMT in women with a thin endometrium after IOA and showed significantly better clinical outcomes than IOA. The authors suggest that the GnRH agonist + HMG protocol should be used for EMT that is less than 7 mm after there has been no optimal response to IOA.


Assuntos
Criopreservação , Transferência Embrionária , Gravidez , Humanos , Feminino , Estudos Retrospectivos , Transferência Embrionária/métodos , Taxa de Gravidez , Estrogênios , Menotropinas , Hormônio Liberador de Gonadotropina , Endométrio/fisiologia , Indução da Ovulação/métodos
9.
Comput Math Methods Med ; 2022: 1456187, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36238467

RESUMO

Objective: Although prolactin (PRL) is known to affect food intake, weight gain, and insulin resistance, its effects on lipid metabolism and underlying mechanisms remain underinvestigated. This study aimed to investigate the effects of PRL and its receptor (PRLR) on fat metabolism in regulating the JAK2/STAT5 signaling pathway. Methods: SW872 adipocytes were incubated with oleic acid to establish an insulin resistance (IR) model. Western blot was used to detect the expression of PRLR, JAK2, p-JAK2, STAT5, and p-STAT5. Triglyceride (TG) mass was detected by chemical colorimetry methods. Results: Fat droplets in the high-dose and medium-dose PRL groups were significantly higher than in the IR model group. TG mass in the cells was increased significantly compared with the model group. Compared with the control group, the expression of PRLR, p-JAK2, and p-STAT5 were significantly decreased in the IR model group when PRL was intervened for 24 h and 48 h. The expression of PRLR, p-JAK2, and p-STAT5 in the high-dose PRL intervention group increased significantly compared with the model group. The PRLR overexpressing group had significantly increased TG content and PRLR, and JAK2, p-JAK2, STAT5, and p-STAT5 levels compared with the IR model. Conclusion: PRL and PRLR are related to fat metabolism, and the PRL/PRLR signaling pathway can promote insulin resistance by activating the JAK2/STAT5 signaling pathway and increasing the deposition of TGs.


Assuntos
Resistência à Insulina , Fator de Transcrição STAT5 , Humanos , Janus Quinase 2/metabolismo , Ácido Oleico/farmacologia , Prolactina/metabolismo , Receptores da Prolactina/genética , Receptores da Prolactina/metabolismo , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais , Triglicerídeos
10.
Angew Chem Int Ed Engl ; 61(30): e202203984, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35538644

RESUMO

Polarization modulation of deep-UV light is of significance to current technologies, and to this end, the birefringent crystal has emerged as an invaluable material as it allows for effective light modulation. Herein, a double-modification strategy driven by F and OH anions that makes double effects towards the critical property enhancement of deep-UV birefringent crystals is proposed. This leads to a new hydroxyborate (NH4 )4 [B12 O16 F4 (OH)4 ] with giant cluster as a deep-UV birefringent crystal with large birefringence (Δnexp. =0.12@546.1 nm). This birefringence is a record among inorganic hydroxyborates with experimentally measured birefringence. Structural analysis shows that the near-plane arrangement of [B12 O16 F4 (OH)4 ] cluster is responsible for the large optical anisotropy. Theoretical calculations indicate that its π-conjugated [BO3 ] and [BO2 OH] units are the main source of this large optical anisotropy.

11.
Chem Commun (Camb) ; 58(37): 5594-5597, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35437534

RESUMO

Although phosphates are a rich source of deep-ultraviolet optical materials, the realization of large optical anisotropy in them still remains a challenge because of the small polarizability anisotropy of [PO4] units. Inspired by the fluoridation strategy and hydrogen bond interaction, a new metal-free monofluorophosphate, (N2H6)[HPO3F]2, was synthesized, which exhibits a large birefringence (cal. 0.077) and wide band gap (∼6.51 eV). Such a large birefringence in (N2H6)[HPO3F]2 sets a new record among available fluorophosphates, and the [HPO3F] unit is theoretically confirmed to be a new birefringence-active unit.

12.
Angew Chem Int Ed Engl ; 61(21): e202202096, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35258151

RESUMO

Discovery of new efficient nonlinear optical (NLO) materials with large second-order nonlinearity for the short-wave ultraviolet spectral region (λPM ≤266 nm, PM=phase-matching) is still very challenging. Herein, a new beryllium-free borate CaZn2 (BO3 )2 with Sr2 Be2 B2 O7 (SBBO) double-layered like configuration was rationally designed, which not only preserves the structural merits but also eliminates the limitations of the SBBO crystal. CaZn2 (BO3 )2 shows a large PM second harmonic generation (SHG) reponse of 3.8×KDP, which is 38 times higher than that of its barium analogue. This enhancement mainly originates from the 1 [Zn2 O6 ]∞ polar chains with a large net dipole moment and [BO3 ] units with a high NLO active density. Our findings show the great significance of the [ZnO4 ] tetrahedra introduced strategy to design beryllium-free SBBO-type NLO crystals and also verify the feasibility of using simple non-isomorphic substitution to induce giant second-order nonlinearity enhancement.

13.
Inorg Chem ; 61(1): 688-692, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34919392

RESUMO

A new alkali-metal iodate, K6(IO6H4)(HI2O6)(HIO3)2(IO3)4·2H2O (KIOH), was successfully grown at room temperature by a slow evaporation method. To our knowledge, the title compound is the first alkali-metal iodate containing isolated [I5+O3] and [I7+O6] units in one structure. Both the bond valence sum and X-ray photoelectron spectroscopy confirmed this phenomenon, which is consistent with the single-crystal data. Also, the theoretical calculation results showed that the title compound is a potential birefringent material. What is more, the low-cost growth of centimeter-sized crystals for the title compound greatly enriches the structural chemistry of the iodate system.

14.
BMC Endocr Disord ; 21(1): 240, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34856980

RESUMO

BACKGROUND: Pentraxin 3 (PTX3) - a crucial humoral innate immunity component - is related to obesity and cardiovascular complications in women who suffer from polycystic ovary syndrome (PCOS). However, the circulating PTX3 level in PCOS is still debated. In this study, we aimed to evaluate PTX3 plasma levels in PCOS women of childbearing age, and find possible endocrine/metabolic factors that could affect this level. METHODS: A total of 360 women were enrolled: 120 PCOS women and 240 body mass index (BMI) matched normally ovulating women. Blood samples were collected on the third day of natural menstrual cycle or from the bleeding after progesterone withdrawal. The PTX3 concentration was measured by immunoassay. RESULTS: The PTX3 plasma level was significantly higher in PCOS women compared to controls. There was a positive correlation between PTX3 plasma level and PCOS diagnosis, overweight, cycle length, serum LH to FSH ratio, estradiol, total testosterone (TT) on the third day of menstrual cycle, antral follicle count (AFC), as well as uric acid. Multivariant linear regression analysis indicated that participants' serum PTX3 levels were proportional to the circulating TT level, existence of PCOS, basal estradiol level and AFC. CONCLUSIONS: Overall, the circulating PTX3 level was elevated in PCOS women and significantly associated with the presence of hyperandrogenism. This study provided the basis for further in-depth researches regarding PTX3 role in PCOS pathophysiology.


Assuntos
Proteína C-Reativa/análise , Hiperandrogenismo/sangue , Síndrome do Ovário Policístico/sangue , Componente Amiloide P Sérico/análise , Adulto , Índice de Massa Corporal , Estudos de Casos e Controles , Estradiol/sangue , Feminino , Humanos , Folículo Ovariano/patologia , Sobrepeso/sangue , Síndrome do Ovário Policístico/patologia , Testosterona/sangue
15.
Front Endocrinol (Lausanne) ; 12: 712855, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34552558

RESUMO

Objective: To evaluate the association between neck circumference (NC) and hyperuricemia in women with polycystic ovary syndrome (PCOS). Methods: This is a cross-sectional study that recruited 601 women with PCOS from January 2018 to January 2021. PCOS was diagnosed according to the Rotterdam definition. Hyperuricemia was defined as serum uric acid level of at least 357 µmol/L. Results: PCOS females with hyperuricemia had significantly greater values of NC, body mass index (BMI), waist circumference (WC) and hip circumference (HC). NC was positively associated with serum uric acid levels, with a standardized regression coefficient of 0.34 after adjusting for confounding factors. Furthermore, logistic regression analysis showed that NC was significantly associated with an increased risk of hyperuricemia, with an adjusted odds ratio of 1.36. The associations between NC and serum uric acid levels were more considerable in those with medium/high BMI (BMI ≥ 21.63 kg/m2), all ranges of WC or medium/high HC (HC ≥ 90 cm). The optimal cut-off point of NC in predicting hyperuricemia was 32.0 cm (Youden index = 0.48), with the sensitivity and negative predictive value of 84.81% and 92.08%, respectively. Conclusions: NC was positively correlated with serum uric acid levels and the prevalence of hyperuricemia in women with PCOS. Therefore, we suggest NC as a simple, novel, and reliable anthropometric measure to be used in the routine clinical assessment of women with PCOS to screen those at high risk of hyperuricemia.


Assuntos
Antropometria , Hiperuricemia/epidemiologia , Pescoço , Síndrome do Ovário Policístico/fisiopatologia , Adulto , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Razão de Chances , Síndrome do Ovário Policístico/patologia , Ácido Úrico/sangue , Circunferência da Cintura
16.
Langmuir ; 37(35): 10403-10412, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34436907

RESUMO

Elaborating the development of functional materials with excellent performance for supercapacitors is important in energy storage devices. In the present study, nanoflower-like MCoP (M = Ni and Fe) composites were successfully fabricated on Ni foam (denoted as NF@MCoP) by a cost-effective hydrothermal and low-temperature phosphating method. Simultaneously, the unique three-dimensional structure, nanoflower morphology, and the conductive substrate provide a favorable large electroactive area, shorter electron transfer distance, and rapid electron conductivity. The as-synthesized nanoflower-like MCoP composites exhibit outstanding energy density, power density, and long-term cycling stability. These results show that the developed electrode materials with excellent performance have great application prospects in the field of supercapacitor applications.

17.
J Vis Exp ; (173)2021 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-34279504

RESUMO

The mechanisms contributing to the natural onset of cerebral venous sinus thrombosis (CVST) are mostly unknown, and a variety of uncontrollable factors are involved in the course of the disease, resulting in great limitations in clinical research. Therefore, the establishment of stable CVST animal models that can standardize a variety of uncontrollable confounding factors have helped to circumvent shortcomings in clinical research. In recent decades, a variety of CVST animal models have been constructed, but the results based on these models have been inconsistent and incomplete. Hence, in order to further explore the pathophysiological mechanisms of CVST, it is necessary to establish a novel and highly compatible animal model, which has important practical value and scientific significance for the diagnosis and treatment of CVST. In the present study, a novel Sprague-Dawley (SD) rat model of superior sagittal sinus (SSS) thrombosis was established via a thread-embolization method, and the stability and reliability of the model were verified. Additionally, we evaluated changes in cerebral venous blood flow in rats after the formation of CVST. Collectively, the SD-rat SSS-thrombosis model represents a novel CVST animal model that is easily established, minimizes trauma, yields good stability, and allows for accurately controlling ischemic timing and location.


Assuntos
Embolia , Trombose dos Seios Intracranianos , Animais , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Seio Sagital Superior
18.
Angew Chem Int Ed Engl ; 60(37): 20469-20475, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34152654

RESUMO

Maximizing the optical anisotropy in birefringent materials has emerged as an efficient route for modulating the polarization-dependent light propagation. Currently, the generation of deep-ultraviolet (deep-UV) polarized light below 200 nm is essential but challenging due to the interdisciplinary significance and insufficiency of high-performing birefringent crystals. Herein, by introducing multiple heteroanionic units, the first sodium difluorodihydroxytriborate-boric acid Na[B3 O3 F2 (OH)2 ]⋅[B(OH)3 ] has been characterized as a novel deep-UV birefringent crystal. Two rare heteroanionic units, [B3 O3 F2 (OH)2 ] and [B(OH)3 ], optimally align to induce large optical anisotropy and also the dangling bonds are eliminated with hydrogens, which results in an extremely large birefringence and band gap. The well-ordered OH/F anions in [B3 O3 F2 (OH)2 ] and [B(OH)3 ] were identified and confirmed by various approaches, and also the origin of large birefringence was theoretically discussed. These results confirm the feasibility of utilizing hydrogen involved heteroanionic units to design crystals with large birefringence, and also expand the alternative system of deep-UV birefringent crystals with new hydroxyfluorooxoborates.

19.
Inorg Chem ; 60(8): 6099-6106, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33823113

RESUMO

Three new tellurates, namely, K2BaPb0.62Ba0.38Te2O9 (1), Rb2BaPb0.7Ba0.3Te2O9 (2), and Ba2KLiTe2O9 (3), with hexagonal triple-perovskite structures have been designed via a cation substitution strategy. All three centrosymmetric compounds crystallize in the same hexagonal space group P63/mmc. In their structures, the [BTe2O9] (B = Pb/Ba for 1 and 2 and Li for 3) groups construct the final three-dimensional framework using face-sharing [Te2O9] dimmers and vertex-linked [BO6] linkages. Meanwhile, the theoretical calculations demonstrate the numerical differences of their birefringence. Thermal stability analysis and differential scanning calorimetry were performed, and UV-vis-NIR diffuse reflectance spectra and infrared spectra of the three title compounds were also characterized and analyzed.

20.
Med Sci Monit ; 26: e916175, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33306667

RESUMO

BACKGROUND This retrospective study aimed to evaluate the predictive value of the follicular output rate (FORT) on the pregnancy outcome of patients with polycystic ovary syndrome (PCOS) undergoing in vitro fertilization and embryo transfer (IVF-ET). MATERIAL AND METHODS Between January 2012 and June 2016, a total of 1,541 patients with PCOS who underwent IVF-ET at our center were enrolled in the study. FORT was calculated as the pre-ovulatory follicle count (PFC)/antral follicle count (AFC)×100%. RESULTS According to the FORT, patients were divided into low, medium, and high FORT groups. With an increase in the FORT, the PFC and serum estradiol at the day of human chorionic gonadotropin (hCG) injection, the number of retrieved oocytes, metaphase II (MII) oocytes, total number of embryos, and number of high-quality embryos significantly increased (P<0.05 and P<0.001) from the low to high FORT groups, while the AFC, gonadotropin (Gn) stimulation day, and total Gn decreased significantly (P<0.001). The live birth rate from frozen embryo transfer and the cumulative live birth rate was the lowest in middle FORT group but increased significantly in high FORT group (P<0.05). The correlation analysis between FORT and related factors showed that the FORT was negatively correlated with body mass index (BMI), Gn stimulation days, and total Gn (P<0.05). CONCLUSIONS FORT is a powerful tool for measuring ovarian reactivity. For patients with PCOS, a high FORT to obtain high-quality embryos and perform frozen embryo transplantation can achieve good pregnancy outcome.


Assuntos
Transferência Embrionária , Fertilização in vitro , Folículo Ovariano/fisiopatologia , Síndrome do Ovário Policístico/fisiopatologia , Resultado da Gravidez , Adulto , Feminino , Humanos , Nascido Vivo , Indução da Ovulação , Valor Preditivo dos Testes , Gravidez , Injeções de Esperma Intracitoplásmicas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...