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1.
Small ; 19(46): e2303847, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37464565

RESUMEN

Chalcohalides not only keep the balance between the nonlinear optical (NLO) coefficient and wide band gap, but also provide a promising solution to achieve sufficient birefringence for phase-matching ability in NLO crystals. In this study, a novel chalcohalide, Cs4 Zn5 P6 S18 I2 (1) is successfully synthesized, by incorporating the highly electropositive Cs and the large electronegative I element into the zinc thiophosphate. Its 3D open framework features an edge-shared by distorted [ZnS4 ], ethanol-like [P2 S6 ], and unusual [ZnS2 I2 ] polyhedrons, which is inconsistent with the soft-hard-acids-bases theory. Remarkably, compound 1 simultaneously exhibits the large second-harmonic generation (SHG, 1.1×AgGaS2 , @1.3 µm) and a wide band gap (3.75 eV) toward a high laser-induced damage threshold (16.7×AgGaS2 , @1.06 µm), satisfying the rigorous requirements for a prominent infrared NLO material with concurrent SHG intensity (≥0.5×AGS) and band gap (≥3.5 eV). Moreover, to the best of the knowledge, the experimental result shows that phase 1 has the largest birefringence (0.108, @546 nm) in chalcohalide and meets phase-matching behavior demand originating from the polarizable anisotropy of NLO-functional motifs. This finding may provide great opportunities for designing birefringent chalcohalides.

2.
Curr Med Imaging ; 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37070449

RESUMEN

BACKGROUND: Extra-adrenal non-functional adrenocortical carcinoma (ACC)is an extremely rare tumor with only eight cases having been reported at different localizations. CASE PRESENTATION: A 60-year-old woman was presented to our hospital with abdominal pain. Magnetic resonance imaging revealed a solitary mass abutting the wall of the small bowel. She underwent resection of the mass, and the results of histopathology and immunohistochemistry were consistent with ACC. CONCLUSION: We report the first occurrence of non-functional adrenocortical carcinoma in the wall of the small bowel in the literature. Magnetic resonance examination is sensitive enough to indicate the accurate location of the tumor and is of great help to clinical operation.

3.
Contraception ; 122: 109999, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36849032

RESUMEN

OBJECTIVES: To assess the effectiveness, safety, and acceptability of postplacental insertion of GyneFix postpartum intrauterine device (PPIUD) in women undergoing cesarean section (C-section). STUDY DESIGN: We conducted a prospective cohort study at 14 hospitals in four eastern coastal provinces of China between September 2017 and November 2020. A total of 470 women who underwent C-section and consented to the postplacental insertion of GyneFix PPIUD were enrolled, and 400 completed the 12-month follow-up. Participants were interviewed in the wards after delivery and followed up at 42 days, and months 3, 6, and 12 after delivery. We used Pearl Index (PI) to measure the rate of contraceptive failure, life-table method to measure the rate of PPIUD discontinuation, including IUD expulsion, and Cox regression model to explore the risk factors associated with discontinuation of the device. RESULTS: Nine pregnancies were detected during the first year after GyneFix PPIUD insertion: seven were due to device expulsion and two occurred with PPIUD in situ. The PIs for overall 1-year pregnancy rate and pregnancies with IUD in situ were 2.3 (95% CI: 1.1-4.4) and 0.5 (95% CI: 0.1-1.9), respectively. The 6- and 12-month cumulative expulsion rates for PPIUD expulsion were 6.3% and 7.6%, respectively. The overall 1-year continuation rate was 86.6% (95% CI: 83.3-89.8). We did not identify any patient with insertion failure, uterine perforation, pelvic infection, or excess bleeding due to GyneFix PPIUD insertion. Women's age, education, occupation, previous history of C-section, parity, and breastfeeding were not associated with removal of GyneFix PPIUD in the first year of use. CONCLUSIONS: Postplacental insertion of GyneFix PPIUD is effective, safe, and acceptable for women undergoing C-section. Expulsion is the most common reason for GyneFix PPIUD discontinuation and pregnancy. The expulsion rate for GyneFix PPIUD is lower than that for framed IUDs, but more evidence is needed for a firm verdict.


Asunto(s)
Dispositivos Intrauterinos de Cobre , Dispositivos Intrauterinos , Embarazo , Femenino , Humanos , Cesárea , Estudios Prospectivos , Periodo Posparto , Expulsión de Dispositivo Intrauterino , Paridad , China , Dispositivos Intrauterinos de Cobre/efectos adversos
4.
Angew Chem Int Ed Engl ; 60(33): 18223-18230, 2021 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-34114311

RESUMEN

Similarities in sizes, shapes, and physical properties between carbon dioxide (CO2 ) and acetylene (C2 H2 ) make it a great challenge to separate the major impurity CO2 from products in C2 H2 production. The use of porous materials is an appealing path to replace current very costly and energy-consuming technologies, such as solvent extraction and cryogenic distillation; however, high CO2 /C2 H2 uptake ratio with minor adsorption of C2 H2 at standard pressure was only unexpectedly observed in scarce examples in recent years although the related research started early at 1950s, and general design strategies to realize this aim are still absent. This work has successfully developed an efficient PIET strategy and obtained the second highest CO2 /C2 H2 adsorption ratio for porous materials in a proof-of-concept MOF with a photochromism-active bipyridinium zwitterion. An unprecedented photocontrollable gate effect, owing to change of interannular dihedral after photoinduced generation of radical species, was also observed for the first time. These findings will inspire design and synthesis of porous materials for high efficient gas adsorption and separation.

5.
Angew Chem Int Ed Engl ; 60(21): 11799-11803, 2021 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-33749981

RESUMEN

Exploring nonlinear optical (NLO) functional motifs (FM, the structural origin of NLO efficiency) is vital for the rational design of NLO materials. Normal spectrum techniques applied in studying photon exciting materials are invalid for NLO materials, in which electrons are not excited substantially but only distorted under laser. A general strategy of determining NLO FM is proposed by comparative studies of experimental electron density (ED) without and under the laser. The in situ experimental ED and wavefunction of typical NLO material LiB3 O5 (LBO) under dark and 360 and 1064 nm lasers are investigated. Compared with the initial state under dark, the ED of [B3 O5 ]- unit at functional states under laser irradiation exhibits remarkable changes of topological atomic and bond properties, confirming the NLO FM being [B3 O5 ]- . The work extracts for the first time the FM of a NLO material experimentally and highlights the crucial role of in situ ED analysis in studying NLO mechanisms.

6.
ACS Sens ; 6(3): 1103-1110, 2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33576603

RESUMEN

The urgent requirement of monitoring air pollution worldwide evokes intensive research interest in developing chemiresistive gas sensing techniques. To overcome the limits in sensitivity and selectivity of room temperature (RT) chemiresistive sensing materials, a new strategy using single-atom catalysts (SACs) via surface coordination is proposed. As a proof-of-concept, single Pd atoms on TiO2 (Pd1-TiO2) possess high efficiency in generating adsorbed O2- as well as high activity and selectivity in catalyzing CO oxidation at RT. As a result, Pd1-TiO2 shows record high sensitivity among the reported RT sensing materials, which is even comparable to those of the best materials working at high temperature. It also provides an approximately 1 order of magnitude lower limit of detection than the best CO sensing materials. Moreover, Pd1-TiO2 presents high selectivity toward 12 kinds of interference gases. This work not only paves a way to design high-performance RT gas sensing materials but also extends the application of SACs.


Asunto(s)
Gases , Catálisis , Oxidación-Reducción , Temperatura
7.
Health Qual Life Outcomes ; 18(1): 54, 2020 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-32131839

RESUMEN

BACKGROUNDS: Social Health Scale for the Elderly short version (SHSE-S) is a psychometrically sound instrument that comprehensively assesses the social health status of older adults in China. The aim of the present study was to establish continuous normative data of SHSE-S. METHODS: We conducted a multicenter cross-sectional study among 31 communities in eastern China. Older adults aged 60 years and above were invited to participate in the study. Each participant was interviewed in-person to finish a structured questionnaire. The SHES-S score was calculated and standardized for each participant. We split the sample into generation and validation datasets and compared the distribution of SHSE-S score between two datasets. Multivariable linear regression was used to assess the SHSE-S score and demographic variables. Regression-based norms were built using a four-step process. RESULTS: A total of 6089 participants (51.2% females) aged 60 years old and above (mean age = 71.3, SD = 8.0) were enrolled as the normative sample. No significant difference was found between the distribution of SHSE-S standardized score in the generation (N = 2392) and validation (N = 3697) datasets. Multivariable linear regression showed that females, higher education levels were positive indicators while aging, living alone, divorced or never married, multimorbidity were negative factors. The regression-based norm which taking demographic factors into account was established and a user-friendly worksheet was also provided to facilitate the scoring and norming of the SHSE-S. CONCLUSIONS: The population-based regression norm of SHSE-S can be a useful tool for assessing the social health status of the Chinese elderly population.


Asunto(s)
Calidad de Vida/psicología , Determinantes Sociales de la Salud/estadística & datos numéricos , Encuestas y Cuestionarios/normas , Anciano , Anciano de 80 o más Años , China , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Ajuste Social , Apoyo Social
8.
J Zhejiang Univ Sci B ; 20(11): 910-919, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31595727

RESUMEN

OBJECTIVE: Mental disorders of the elderly population in China deserve attention. Social health is significantly associated with depression. This study aimed to evaluate the rate of depressive symptoms and to test the relationships between social health and depressive symptoms among a large sample of community-dwelling elderly adults. METHODS: We conducted a cross-sectional study among community-dwelling adults aged 60 years or above in Zhejiang Province, China. Face-to-face interviews were used to complete a structured questionnaire for all participants. We used the Social Health Scale for the Elderly (SHSE) to evaluate social health status and used the short form of the Geriatric Depression Scale to evaluate depressive symptoms. Multivariate logistic regression was used to evaluate the association between social health status and depressive symptoms. RESULTS: Of the total of 3757 participants included, 1887 (50.23%) were female, and the mean±standard deviation (SD) age was (70.0±8.3) years. The rate of depressive symptoms was 25.92%. The social health score was higher in non-depressed participants than in depressed participants (raw score 50.7 vs. 48.3, P<0.001). Participants with "moderate" or "good" social health had a significantly lower risk of depressive symptoms than those with "poor" social health (odds ratio (OR)=0.55, 95% confidence interval (CI): 0.46-0.66 for moderate social health; OR=0.45, 95% CI: 0.35-0.60 for good social health). The association between social health and depressive symptoms was consistent across several subgroups. CONCLUSIONS: Social health is significantly inversely associated with depressive symptoms. The SHSE may serve as an efficient screener to identify those elderly adults with social health deficits, but systematic assessment to guide intervention merits further investigation.


Asunto(s)
Depresión/epidemiología , Estado de Salud , Vida Independiente , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad
9.
Phys Chem Chem Phys ; 17(17): 11499-508, 2015 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25854200

RESUMEN

Density functional theory (DFT) calculations are employed to investigate the reactivity of tungsten oxide clusters towards carbon monoxide. Extensive structural searches show that all the ground-state structures of (WO3)n(+) (n = 1-4) contain an oxygen radical center with a lengthened W-O bond which is highly active in the oxidation of carbon monoxide. Energy profiles are calculated to determine the reaction mechanisms and evaluate the effect of cluster sizes. The monomer WO3(+) has the highest reactivity among the stoichiometric clusters of different sizes (WO3)n(+) (n = 1-4). The reaction mechanisms for CO with mono-nuclear stoichiometric tungsten oxide clusters with different charges (WO3(-/0/+)) are also studied to clarify the influence of charge states. Our calculated results show that the ability to oxidize CO gets weaker from WO3(+) to WO3(-) as the negative charge accumulates progressively.

10.
World J Gastroenterol ; 20(38): 13981-6, 2014 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-25320536

RESUMEN

AIM: To evaluate the efficacy, safety and feasibility of endoscopic full-thickness resection (EFR) for the treatment of gastric submucosal tumors (SMTs) arising from the muscularis propria. METHODS: A total of 35 gastric SMTs arising from the muscularis propria layer were resected by EFR between January 2010 and September 2013. EFR consists of five major steps: injecting normal saline into the submucosa; pre-cutting the mucosal and submucosal layers around the lesion; making a circumferential incision as deep as the muscularis propria around the lesion using endoscopic submucosal dissection and an incision into the serosal layer around the lesion with a Hook knife; a full-thickness resection of the tumor, including the serosal layer with a Hook or IT knife; and closing the gastric wall with metallic clips. RESULTS: Of the 35 gastric SMTs, 14 were located at the fundus, and 21 at the corpus. EFR removed all of the SMTs successfully, and the complete resection rate was 100%. The mean operation time was 90 min (60-155 min), the mean hospitalization time was 6.0 d (4-10 d), and the mean tumor size was 2.8 cm (2.0-4.5 cm). Pathological examination confirmed the presence of gastric stromal tumors in 25 patients, leiomyomas in 7 and gastric autonomous nerve tumors in 2. No gastric bleeding, peritonitis or abdominal abscess occurred after EFR. Postoperative contrast roentgenography on the third day detected no contrast extravasation into the abdominal cavity. The mean follow-up period was 6 mo, with no lesion residue or recurrence noted. CONCLUSION: EFR is efficacious, safe and minimally invasive for patients with gastric SMTs arising from the muscularis propria layer. This technique is able to resect deep gastric lesions while providing precise pathological information about the lesion. With the development of EFR, the indications of endoscopic resection might be extended.


Asunto(s)
Gastrectomía/métodos , Mucosa Gástrica/cirugía , Gastroscopía/métodos , Neoplasias Gástricas/cirugía , Adulto , Anciano , Estudios de Factibilidad , Femenino , Gastrectomía/efectos adversos , Mucosa Gástrica/patología , Gastroscopía/efectos adversos , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Tempo Operativo , Neumoperitoneo/etiología , Neumoperitoneo/terapia , Punciones , Estudios Retrospectivos , Neoplasias Gástricas/patología , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
11.
World J Gastroenterol ; 20(38): 14076-8, 2014 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-25320550

RESUMEN

The small intestine is approximately 5-6 m long and occupies a large area in the abdominal cavity. These factors preclude the use of ordinary endoscopy and X-ray to thoroughly examine the small intestine for bleeding of vascular malformations. Thus, the diagnosis of intestinal bleeding is very difficult. A 47-year-old man presented at the hospital 5 mo ago with dark stool. Several angiomas were detected by oral approach enteroscopy, but no active bleeding was observed. Additionally, no lesions were detected by anal approach enteroscopy; however, gastrointestinal tract bleeding still occurred for an unknown reason. We performed an abdominal vascular enhanced computed tomography examination and detected ileal vascular malformations. Ileum angioma and vascular malformation were detected by a laparoscopic approach, and segmental resection was performed for both lesions, which were confirmed by pathological diagnosis. This report systemically emphasizes the imaging findings of small intestinal vascular malformation bleeding.


Asunto(s)
Malformaciones Arteriovenosas/complicaciones , Hemorragia Gastrointestinal/etiología , Íleon/irrigación sanguínea , Arteria Mesentérica Superior/anomalías , Malformaciones Arteriovenosas/diagnóstico , Malformaciones Arteriovenosas/cirugía , Biopsia , Endoscopía Gastrointestinal , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/cirugía , Hemangioma/complicaciones , Hemangioma/cirugía , Humanos , Neoplasias del Íleon/complicaciones , Neoplasias del Íleon/cirugía , Masculino , Arteria Mesentérica Superior/diagnóstico por imagen , Arteria Mesentérica Superior/cirugía , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
12.
World J Gastroenterol ; 20(25): 8253-9, 2014 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-25009400

RESUMEN

AIM: To assess the effectiveness of endoscopic full-thickness resection (EFR) and laparoscopic surgery in the treatment of gastric stromal tumors arising from the muscularis propria. METHODS: Out of 62 gastric stromal tumors arising from the muscularis propria, each > 1.5 cm in diameter, 32 were removed by EFR, and 30 were removed by laparoscopic surgery. The tumor expression of CD34, CD117, Dog-1, S-100, and SMA was assessed immunohistochemically. The operative time, complete resection rate, length of hospital stay, incidence of complications, and recurrence rate were compared between the two groups. Continuous data were compared using independent samples t-tests, and categorical data were compared using χ (2) tests. RESULTS: The 32 gastric stromal tumors treated by EFR and the 30 treated by laparoscopic surgery showed similar operative time [20-155 min (mean, 78.5 ± 30.1 min) vs 50-120 min (mean, 80.9 ± 46.7 min), P > 0.05], complete resection rate (100% vs 93.3%, P > 0.05), and length of hospital stay [4-10 d (mean, 5.9 ± 1.4 d) vs 4-19 d (mean, 8.9 ± 3.2 d), P >0.05]. None of the patients treated by EFR experienced complications, whereas two patients treated by laparoscopy required a conversion to laparotomy, and one patient had postoperative gastroparesis. No recurrences were observed in either group. Immunohistochemical staining showed that of the 62 gastric stromal tumors diagnosed by gastroscopy and endoscopic ultrasound, six were leiomyomas (SMA-positive), one was a schwannoglioma (S-100 positive), and the remaining 55 were stromal tumors. CONCLUSION: Some gastric stromal tumors arising from the muscularis propria can be completely removed by EFR. EFR could likely replace surgical or laparoscopic procedures for the removal of gastric stromal tumors.


Asunto(s)
Gastrectomía/métodos , Tumores del Estroma Gastrointestinal/cirugía , Gastroscopía , Laparoscopía , Leiomioma/cirugía , Neurilemoma/cirugía , Neoplasias Gástricas/cirugía , Adulto , Anciano , Biomarcadores de Tumor/análisis , Distribución de Chi-Cuadrado , China , Femenino , Gastrectomía/efectos adversos , Tumores del Estroma Gastrointestinal/química , Tumores del Estroma Gastrointestinal/patología , Gastroscopía/efectos adversos , Humanos , Inmunohistoquímica , Laparoscopía/efectos adversos , Leiomioma/química , Leiomioma/patología , Tiempo de Internación , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Neurilemoma/química , Neurilemoma/patología , Tempo Operativo , Complicaciones Posoperatorias/terapia , Estudios Retrospectivos , Neoplasias Gástricas/química , Neoplasias Gástricas/patología , Factores de Tiempo , Resultado del Tratamiento
13.
J Phys Chem A ; 117(14): 3093-9, 2013 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-23496349

RESUMEN

Density functional theory (DFT) calculations are employed to investigate the structural and electronic properties of bare tritungsten clusters (W3, W3(-), W3(2-)) and tritungsten oxide clusters W3Ox(-/0) (x = 1, 2). Generalized Koopmans' theorem is applied to predict the vertical detachment energies and simulate the photoelectron spectra (PES) for W3Ox(-) (x = 0-2) clusters. Extensive DFT calculations are performed in search of the lowest energy structures for both the anions and the neutrals. The bare tritungsten clusters are predicted to be triangular structures with D3h ((3)A1'), C2v ((2)A1) and D3h ((1)A1') symmetry for W3, W3(-) and W3(2-), respectively. For W3O(-) and W3O clusters, the oxygen atom occupies the terminal site, while the next added oxygen atom is found to be a bridging one in both W3O2(-) and W3O2 clusters. Molecular orbital analyses are carried out to elucidate the chemical bonding of these clusters and provide insights into the sequential oxidation from W3(-) to W3O2(-). Partial σ- and δ-aromaticity are revealed in the neutral W3 (D3h, (3)A1'), while the anion W3(2-) (D3h, (1)A1') possesses only δ-aromaticity.

14.
J Phys Chem A ; 117(6): 1042-52, 2013 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-22671951

RESUMEN

The electronic and structural properties of monohafnium oxide clusters, HfO(n)(-) and HfO(n) (n = 1-6), are investigated using anion photoelectron spectroscopy and density-functional theory at the B3LYP level. The observed ground-state adiabatic detachment energy is low for HfO(-) (0.5 ± 0.1 eV) and HfO(2)(-) (2.125 ± 0.010 eV), roughly constant for HfO(3)(-) (3.6 ± 0.1 eV), HfO(4)(-) (3.67 ± 0.05 eV), and HfO(5)(-) (3.9 ± 0.1 eV), and substantially higher for HfO(6)(-) (4.9 ± 0.1 eV). Activated oxygen species, such as radical, superoxide, peroxide, diradical, and triradical, are identified in the HfO(n)(-) and HfO(n) clusters. The Hf center is shown to be flexible to accommodate the oxygen species. The sum of formal Hf-O bond orders around the Hf center is equal to four for all of the neutral clusters studied, and five for all of the anions. The O-rich HfO(n)(-) and HfO(n) (n = 3-6) clusters provide well-defined molecular models to understand O(2) adsorption and activation on an Hf center.

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