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1.
Heliyon ; 10(15): e35507, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39166026

RESUMO

Optical paths in telescopes frequently incorporate silver mirrors for high sensitivity. Unfortunately, silver mirrors without protective coatings are susceptible to sulfurization and oxidation, compromising their quality. Even with protective layers, insufficient adhesion between the coating and the silver film can lead to peeling, exposing the silver to external environments and affecting its quality. This study aimed to identify dielectric materials with superior adhesion to silver, rendering them ideal choices for silver coating applications. By electron gun evaporation, different dielectric layers were deposited on the top and bottom of the silver film under a substrate temperature below 150 °C. These coatings were composed of materials with desired refractive indices, including aluminum oxide (Al2O3), aluminum-doped silicon, magnesium fluoride (MgF2), and other dielectrics. Following the deposition, a tape adhesion test was conducted to evaluate the bond strength of the samples. X-ray photoelectron spectroscopy (XPS) analysis was carried out to investigate the interaction between silver and its neighboring layers. The results revealed that Al2O3 and MgF2 exhibited exceptional adhesion to silver. Moreover, these multilayer coatings can effectively enhance the reflectance of silver in the visible (VIS) wavelength ranges.

2.
Phys Rev E ; 110(1): L012802, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39160931

RESUMO

A steel ball with a density higher than that of water can bounce on a water surface when heated to a temperature well above the Leidenfrost point. In this letter, an experiment is conducted where heated steel balls are released onto a water surface. The heated steel ball descends into the liquid, thus causing the liquid to evaporate and form a vapor cushion with an upward force that lifts the steel ball. Subsequently, the steel ball bounces off the water surface, like a solid ball bouncing off an elastic surface without sinking into the water. This phenomenon is known as the inverse Leidenfrost effect. In this letter, we evaluate the various motion behaviors of spheres at different Reynolds numbers and temperatures. Additionally, we analyze the bouncing behavior of solid spheres on a free liquid surface and examine the various force components.

3.
World J Exp Med ; 14(2): 88867, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38948422

RESUMO

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease in which multiple organs are damaged that prevails in fertile women. Currently, glucocorticoids and immunosuppressants are widely used to treat SLE patients. However, ovarian dysfunction occurs following the use of these drugs in women with SLE. Here, we summarize recent progress in terms of understanding ovarian injury, the effects of drug application and strategies to improve ovarian function in women with SLE. This review could be helpful to precisely cure SLE in women desiring to have offspring.

4.
World J Stem Cells ; 16(3): 245-256, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38577237

RESUMO

Mesenchymal stem cells (MSCs) are stem/progenitor cells capable of self-renewal and differentiation into osteoblasts, chondrocytes and adipocytes. The transformation of multipotent MSCs to adipocytes mainly involves two subsequent steps from MSCs to preadipocytes and further preadipocytes into adipocytes, in which the process MSCs are precisely controlled to commit to the adipogenic lineage and then mature into adipocytes. Previous studies have shown that the master transcription factors C/enhancer-binding protein alpha and peroxisome proliferation activator receptor gamma play vital roles in adipogenesis. However, the mechanism underlying the adipogenic differentiation of MSCs is not fully understood. Here, the current knowledge of adipogenic differentiation in MSCs is reviewed, focusing on signaling pathways, noncoding RNAs and epigenetic effects on DNA methylation and acetylation during MSC differentiation. Finally, the relationship between maladipogenic differentiation and diseases is briefly discussed. We hope that this review can broaden and deepen our understanding of how MSCs turn into adipocytes.

5.
Polymers (Basel) ; 16(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38611132

RESUMO

In low-pressure wax injection molding, cooling time refers to the period during which the molten plastic inside the mold solidifies and cools down to a temperature where it can be safely ejected without deformation. However, cooling efficiency for the mass production of injection-molded wax patterns is crucial. This work aims to investigate the impact of varying surface roughness on the inner walls of the cooling channel on the cooling efficiency of an aluminum-filled epoxy resin rapid tool. It was found that the cooling time for the injection-molded products can be determined by the surface roughness according to the proposed prediction equation. Employing fiber laser processing on high-speed steel rods allows for the creation of microstructures with different surface roughness levels. Results demonstrate a clear link between the surface roughness of cooling channel walls and cooling time for molded wax patterns. Employing an aluminum-filled epoxy resin rapid tool with a surface roughness of 4.9 µm for low-pressure wax injection molding can save time, with a cooling efficiency improvement of approximately 34%. Utilizing an aluminum-filled epoxy resin rapid tool with a surface roughness of 4.9 µm on the inner walls of the cooling channel can save the cooling time by up to approximately 60%. These findings underscore the significant role of cooling channel surface roughness in optimizing injection molding processes for enhanced efficiency.

6.
BMC Pregnancy Childbirth ; 24(1): 143, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368325

RESUMO

PURPOSE: Acknowledging the associated risk factors may have a positive impact on reducing the incidence of ectopic pregnancy (EP). In recent years, body mass index (BMI) has been mentioned in research. However, few studies are available and controversial on the relationship between EP and BMI. METHODS: We retrospectively studied the EP women as a case group and the deliveries as a control group in the central hospital of Wuhan during 2017 ~ 2021. χ2 test of variables associated with ectopic pregnancy was performed to find differences. Univariate and multivariate binary logistic regression analysis was conducted to analyze the association of the variables of age, parity, history of induced abortion, history of ectopic pregnancy, history of spontaneous abortion, history of appendectomy surgery and BMI (< 18.5 kg/m2, 18.5 ~ 24.9 kg/m2, 25 kg/m2 ~ 29.9 kg/m2, ≥ 30 kg /m2) with EP. RESULTS: They were 659 EP and 1460 deliveries. The variables of age, parity, history of induced abortion, history of ectopic pregnancy and BMI were different significantly(P < 0.05). Multivariate analysis showed that the variables of age > 35 years old [(OR (Odds Ratio), 5.415; 95%CI (Confidence Interval), 4.006 ~ 7.320, P < 0.001], history of ectopic pregnancy (OR, 3.944; 95%CI, 2.405 ~ 6.467; P < 0.001), history of induced abortion(OR, 3.365; 95%CI, 2.724 ~ 4.158, P < 0.001) and low BMI (< 18.5 kg/m2) (OR, 1.929; 95%CI, 1.416 ~ 2.628, P < 0.001])increased the risk of EP. CONCLUSION: The history of ectopic pregnancy, history of induced abortion and age > 35 years old were the risk factors with EP. In addition to these traditional factors, we found low BMI (< 18.5 kg/m2) with women may increase the risk to EP.


Assuntos
Aborto Induzido , Gravidez Ectópica , Gravidez , Feminino , Humanos , Adulto , Estudos Retrospectivos , Estudos de Casos e Controles , Índice de Massa Corporal , Gravidez Ectópica/epidemiologia , Gravidez Ectópica/etiologia , Aborto Induzido/efeitos adversos , Fatores de Risco
7.
Sci Rep ; 14(1): 937, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38195767

RESUMO

Notwithstanding recent advances in direct antiviral specialists (DAAs) for hepatitis C infection (HCV), it is yet a pervasive overall issue in patients with rheumatoid arthritis (RA). Exosomal microRNAs (miRNAs) is associated with HCV infection. However, it remains unknown how miRNAs respond following biologic disease-modifying antirheumatic drug (bDMARD) and targeted synthetic DMARD (tsDMARD) treatment in HCV patients with RA. We prospectively recruited RA patients taking anti-tumor necrosis factor-α (TNF-α) inhibitors rituximab (RTX) and tofacitinib. The serum hepatitis C viral load was measured using real-time quantitative reverse transcriptase PCR before and 6 months after bDMARD and tsDMARD therapy. HCV RNA replication activity was measured using an HCV-tricistronic replicon reporter system, and quantitative analysis of hsa-mir-122-5p and hsa-mir-155-5p in patients was performed using quantitative PCR. HCV RNA replication in hepatocytes was not affected by tofacitinib or TNF-α inhibitor treatment. Hsa-mir-155-5p and hsa-mir-122-5p were significantly expanded in RA patients with HCV as compared with those without HCV. We observed a dramatic increase in hsa-mir-122-5p and a decrease in hsa-mir-155-5p expression levels in patients taking RTX in comparison with other treatments. Finally, a reduction in hsa-mir-122-5p and an increase in hsa-mir-155-5p were observed in a time-dependent manner after tofacitinib and DAA therapy in RA-HCV patients. These results showed that hsa-mir-155-5p and hsa-mir-122-5p were significantly increased in RA-HCV patients as compared with those without HCV after taking tofacitinib. Hsa-mir-155-5p and hsa-mir-122-5p may be potential biomarkers for treatment efficacy in RA patients with HCV.


Assuntos
Antirreumáticos , Artrite Reumatoide , Hepatite C Crônica , Hepatite C , MicroRNAs , Humanos , MicroRNAs/genética , Antivirais/farmacologia , Antivirais/uso terapêutico , Fator de Necrose Tumoral alfa , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C/genética , Replicação Viral , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/genética , Rituximab , Antirreumáticos/farmacologia , Antirreumáticos/uso terapêutico , Biomarcadores
8.
Acta cir. bras ; 27(5): 338-342, May 2012. ilus
Artigo em Inglês | LILACS | ID: lil-626249

RESUMO

PURPOSE: To study the effects of percutaneous reconstruction plate internal fixation in the treatment of unstable sacral fractures. METHODS: Percutaneous reconstruction plate internal fixation was applied on 21 cases of unstable sacral fracture (15 males and six females, at age range of 16-65 years, mean 38.3 years) including four cases of Denis Zone I, 14 cases of Zone II and three cases of Zone III. In operation, an arc incision (about 3-5 cm long) was made along the iliac crest on the outside border of posterior superior iliac spine (PSIS) on both sides, and then the plate was transported from the wounded side to the opposite one through the subcutaneous tunnel. RESULTS: The mean incision length, operation time, intraoperative blood loss was 4.3cm, 45.2min, and 160.8ml respectively. All these patients were followed up for 12-33 months (average 16.3 months), which showed no incision infection, intraoperative neurovascular injury, internal fixation loose or breakage, disunion, or obvious lower limb length inequality. The function result was rated as excellent in six cases, good in 12 and fair in 3, with excellence rate of 85.7%, according to the Majeed scoring system. CONCLUSION: Percutaneous reconstruction plate internal fixation is an ideal surgical approach to unstable sacral fractures, as it is easy, safe, causing less trauma and fewer complications, and conducive to quicker recovery.


OBJETIVO: Estudar os efeitos da reconstrução percutânea com fixação de placa interna no tratamento de fraturas sacrais instáveis. MÉTODOS: A reconstrução percutânea com fixação de placa interna foi aplicada em 21 casos de fratura sacral instável (15 homens e seis mulheres, com idade variando entre 16 e 65 anos, média de 38,3 anos) incluindo quatro casos de Zona I de Denis, 14 casos de Zona II e três casos de Zona III. No ato operatório, uma incisão arqueada (cerca de 3 a 5cm de comprimento) foi feita ao longo da crista ilíaca na borda externa da espinha ilíaca supero-posterior (PSIS) em ambos os lados, e então a placa foi transportada do lado da ferida para o lado oposto através do túnel subcutâneo. RESULTADOS: O comprimento médio da incisão, tempo operatório e perda sanguínea intra-operatória foram, respectivamente, 4,3cm, 45,2min e 160,8ml. Todos estes pacientes foram acompanhados por 12 a 33 meses (média 16,3 meses), o que mostrou nenhuma infecção de ferida operatória, lesão neurovascular intraoperatória, perda da fixação interna ou quebra, desunião ou desigualdade nos comprimentos dos membros inferiores. O resultado funcional foi excelente em seis casos, bom em doze e falho em três, com taxa excelente de 85,7%, de acordo com o sistema de escore de Majeed. CONCLUSÃO: Reconstrução percutânea com fixação de placa interna é uma abordagem cirúrgica ideal para fraturas sacrais instáveis, sendo fácil e segura, causando menos trauma e poucas complicações, conduzindo a uma recuperação mais rápida.


Assuntos
Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Placas Ósseas , Fixação Interna de Fraturas/métodos , Sacro/lesões , Fraturas da Coluna Vertebral/cirurgia , Período Pós-Operatório
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