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1.
Sensors (Basel) ; 24(13)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-39000881

RESUMO

Conventionally, the electromechanical system requires the installation of auxiliary displacement sensors and only the amount on the drive part and motion end, which increases volume, cost, and measurement error in the system. This paper presents an integrated measurement method with a sensing head, which takes the equal division characteristics of mechanical structures as part of the sensor, thus, the so-called self-sensing system. Moreover, the displacement is measured by counting the time pulses. The sensing head is integrated with the entire electromechanical system, including the driving, transmitting, and moving parts. Thus, the integration of the sensing part is greatly improved. Taking the rotary table as a special example, and the sensing head embedded into each part of the system, displacement information is obtained by the common processing system and fused by the adaptive weighted average method. The results of the experiment show that the fusion precision of each component is higher than only the motor position information as the feedback. The proposed method is a practical self-sensing technology with significant volume reduction and intelligent control benefits in the industry, especially suitable for extremely small and narrow spaces.

2.
iScience ; 27(6): 109900, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38883837

RESUMO

Type 2 diabetes mellitus (T2DM) represents a common complication during pregnancy that affects fetoplacental development. We demonstrated the existence of impaired trophoblast syncytialization under hyperglycemic conditions. However, the exact mechanism remains unknown. RNA N6-methyladenosine (m6A) is an emerging regulatory mechanism of mRNA and participates in various biological processes. We described the global m6A modification pattern in T2DM placenta by the combined analysis of methylated RNA immunoprecipitation sequencing (MeRIP-Seq) and RNA sequencing (RNA-Seq). Both the m6A modification and expression of SIK1, which is critical for syncytialization, were significantly decreased in trophoblast exposed to hyperglycemic conditions. In addition, the m6A demethylase fat mass and obesity-associated protein (FTO) affects the expression and mRNA stability of SIK1 by binding to its 3'-untranslated region (UTR) m6A site. This work reveals that the FTO-m6A-SIK1 axis plays critical roles in regulating syncytialization in the placenta.

3.
ACS Appl Mater Interfaces ; 16(25): 32334-32343, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38861694

RESUMO

Transition metal thiophosphates (MTPs) are a group of emerging van der Waals materials with widely tunable band gaps. In the MTP family, CdPSe3 is demonstrated to possess a wide energy band gap and high carrier mobility, making it a potential candidate in optoelectronic applications. Here, we reported photoelectric response behaviors of both CdPSe3- and CdPSe3/MoS2-based photodetectors (noted as CPS and CM, respectively); these showed prominent photoelectric performances, and the latter proved to be significantly superior to the former. These devices exhibited ultralow dark current at a magnitude order of 10-12 A and fine cycle and air stabilities. Compared with CPS, CM demonstrated the highest responsivity (91.12 mA/W) and detectivity (1.74 × 1011 Jones) at 5 V under 425 nm light illumination. Besides, CM showed self-powered photoelectric responses at zero bias, which was attributed to the improved separation efficiency of photogenerated carriers by the built-in electric field at the interface of the p-n junction. This work proves a prospect for the CM device in portable, self-powered optoelectronic device applications.

4.
Nat Prod Res ; : 1-4, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693720

RESUMO

Hydroxytyrosol acetate is one of the polyphenolic compounds in olive leaves. Hydroxytyrosol acetate has a variety of biological activities, such as antibacterial, antioxidant, anti-inflammatory, cognitive improvement and neuroprotective effects. However, there is no report on the antitumor activity and the antitumor mechanism of hydroxytyrosol acetate. In our study, we studied the antitumor activity of hydroxytyrosol acetate by MTT assay and determined the antitumor mechanism by DNA ladder assay, mitochondrial membrane potential assay and western blot assay. We found that hydroxytyrosol acetate could inhibit cell proliferation, and the inhibition rate was 78.08%. The further researches showed that hydroxytyrosol acetate could downregulate Bcl-2 protein while upregulate Bax protein. It also could induce mitochondrial depolarisation and release of cytochrome C. These results indicated that hydroxytyrosol acetate might induce BEL7402 cells apoptosis via mitochondrial pathway.

5.
Front Cell Infect Microbiol ; 14: 1382145, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38736748

RESUMO

Carbapenem-resistant Acinetobacter baumannii (CRAB) has become a new threat in recent years, owing to its rapidly increasing resistance to antibiotics and new effective therapies are needed to combat this pathogen. Phage therapy is considered to be the most promising alternative for treating CRAB infections. In this study, a novel phage, Ab_WF01, which can lyse clinical CRAB, was isolated and characterized from hospital sewage. The multiplicity of infection, morphology, one-step growth curve, stability, sensitivity, and lytic activity of the phage were also investigated. The genome of phage Ab_WF01 was 41, 317 bp in size with a GC content of 39.12% and encoded 51 open reading frames (ORFs). tRNA, virulence, and antibiotic resistance genes were not detected in the phage genome. Comparative genomic and phylogenetic analyses suggest that phage Ab_WF01 is a novel species of the genus Friunavirus, subfamily Beijerinckvirinae, and family Autographiviridae. The in vivo results showed that phage Ab_WF01 significantly increased the survival rate of CRAB-infected Galleria mellonella (from 0% to 70% at 48 h) and mice (from 0% to 60% for 7 days). Moreover, after day 3 post-infection, phage Ab_WF01 reduced inflammatory response, with strongly ameliorated histological damage and bacterial clearance in infected tissue organs (lungs, liver, and spleen) in mouse CRAB infection model. Taken together, these results show that phage Ab_WF01 holds great promise as a potential alternative agent with excellent stability for against CRAB infections.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Bacteriófagos , Carbapenêmicos , Genoma Viral , Terapia por Fagos , Filogenia , Esgotos , Acinetobacter baumannii/virologia , Acinetobacter baumannii/efeitos dos fármacos , Esgotos/virologia , Esgotos/microbiologia , Animais , Carbapenêmicos/farmacologia , Bacteriófagos/genética , Bacteriófagos/fisiologia , Bacteriófagos/classificação , Bacteriófagos/isolamento & purificação , Infecções por Acinetobacter/microbiologia , Camundongos , Antibacterianos/farmacologia , Fases de Leitura Aberta , Modelos Animais de Doenças , Mariposas/virologia , Mariposas/microbiologia , Composição de Bases
6.
Front Oncol ; 14: 1376496, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38741782

RESUMO

FOXK2, a member of the Forkhead box K (FOXK) transcription factor family, is widely expressed in various tissues and organs throughout the body. FOXK2 plays crucial roles in cell proliferation, differentiation, autophagy, de novo nucleotide biosynthesis, DNA damage response, and aerobic glycolysis. Although FOXK2 is recognized as an oncogene in colorectal cancer and hepatocellular carcinoma, it acts as a tumor suppressor in breast cancer, cervical cancer, and non-small cell lung cancer (NSCLC). This review provides an overview of the recent progress in understanding the regulatory mechanisms of FOXK2 and its downstream targets, highlights the significant impact of FOXK2 dysregulation on cancer etiology, and discusses the potential of targeting FOXK2 for cancer treatment.

7.
BMC Microbiol ; 24(1): 161, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730357

RESUMO

Gestational diabetes mellitus (GDM) is characterized by insulin resistance and low-grade inflammation, and most studies have demonstrated gut dysbiosis in GDM pregnancies. Overall, they were manifested as a reduction in microbiome diversity and richness, depleted short chain fatty acid (SCFA)-producing genera and a dominant of Gram-negative pathogens releasing lipopolysaccharide (LPS). The SCFAs functioned as energy substance or signaling molecules to interact with host locally and beyond the gut. LPS contributed to pathophysiology of diseases through activating Toll-like receptor 4 (TLR4) and involved in inflammatory responses. The gut microbiome dysbiosis was not only closely related with GDM, it was also vital to fetal health through vertical transmission. In this review, we summarized gut microbiota signature in GDM pregnancies of each trimester, and presented a brief introduction of microbiome derived SCFAs. We then discussed mechanisms of microbiome-host interactions in the physiopathology of GDM and associated metabolic disorders. Finally, we compared offspring microbiota composition from GDM with that from normal pregnancies, and described the possible mechanism.


Assuntos
Diabetes Gestacional , Disbiose , Ácidos Graxos Voláteis , Microbioma Gastrointestinal , Diabetes Gestacional/microbiologia , Diabetes Gestacional/metabolismo , Humanos , Gravidez , Feminino , Disbiose/microbiologia , Ácidos Graxos Voláteis/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Bactérias/isolamento & purificação , Interações entre Hospedeiro e Microrganismos , Lipopolissacarídeos/metabolismo
8.
J Ovarian Res ; 17(1): 98, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38725001

RESUMO

Ovarian Hyperstimulation Syndrome (OHSS) is a systemic condition marked by the enlargement of the ovaries and heightened vascular permeability. And hypothyroidism (HT) emerges as a potential risk factor for OHSS occurrence. This review presented a comprehensive summary of pertinent case reports involving patients diagnosed with both HT and OHSS. Detailed exploration was conducted into their clinical presentations, diagnostic methodologies, and treatment modalities. Additionally, the review delved into potential interaction mechanisms between HT and OHSS, encompassing various aspects including hormone levels. Moreover, management strategies for mitigating the risk of OHSS in HT patients were thoroughly reviewed and the importance of monitoring thyroid function in those experiencing OHSS was emphasized. This review indicated that the association between HT and OHSS, underscoring its multifaceted complexity. It could accentuate the ongoing necessity for rigorous research and clinical refinement to deepen our comprehension of this association and to bolster diagnostic and therapeutic methodologies for optimal patient care. In conclusion, this review offered valuable insights for future research directions and clinical practices for patients afflicted with OHSS and HT.


Assuntos
Hipotireoidismo , Síndrome de Hiperestimulação Ovariana , Humanos , Síndrome de Hiperestimulação Ovariana/complicações , Síndrome de Hiperestimulação Ovariana/terapia , Síndrome de Hiperestimulação Ovariana/etiologia , Hipotireoidismo/complicações , Feminino , Fatores de Risco
9.
Int J Nanomedicine ; 19: 3315-3332, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617797

RESUMO

Background: Acute myocardial infarction (AMI) is a common cardiovascular disease in clinic. Currently, there is no specific treatment for AMI. Carbon dots (CDs) have been reported to show excellent biological activities, which hold promise for the development of novel nanomedicines for the treatment of cardiovascular diseases. Methods: In this study, we firstly prepared CDs from the natural herb Curcumae Radix Carbonisata (CRC-CDs) by a green, simple calcination method. The aim of this study is to investigate the cardioprotective effect and mechanism of CRC-CDs on isoproterenol (ISO) -induced myocardial infarction (MI) in rats. Results: The results showed that pretreatment with CRC-CDs significantly reduced serum levels of cardiac enzymes (CK-MB, LDH, AST) and lipids (TC, TG, LDL) and reduced st-segment elevation and myocardial infarct size on the ECG in AMI rats. Importantly, cardiac ejection fraction (EF) and shortening fraction (FS) were markedly elevated, as was ATPase activity. In addition, CRC-CDs could significantly increase the levels of superoxide dismutase (SOD), reduced glutathione (GSH), catalase (CAT), and reduce the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) in myocardial tissue, thereby exerting cardioprotective effect by enhancing the antioxidant capacity of myocardial tissue. Moreover, the TUNEL staining image showed that positive apoptotic cells were markedly declined after CRC-CDs treatment, which indicate that CRC-CDs could inhibit cardiomyocyte apoptosis. Importantly, The protective effect of CRC-CDs on H2O2 -pretreated H9c2 cells was also verified in vitro. Conclusion: Taken together, CRC-CDs has the potential for clinical application as an anti-myocardial ischemia drug candidate, which not only provides evidence for further broadening the biological application of cardiovascular diseases, but also offers potential hope for the application of nanomedicine to treat intractable diseases.


Assuntos
Infarto do Miocárdio , Isquemia Miocárdica , Animais , Ratos , Peróxido de Hidrogênio , Infarto do Miocárdio/tratamento farmacológico , Miocárdio , Carbono
10.
FEBS Lett ; 598(9): 959-977, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38644468

RESUMO

Reversible S-acylation plays a pivotal role in various biological processes, modulating protein functions such as subcellular localization, protein stability/activity, and protein-protein interactions. These modifications are mediated by acyltransferases and deacylases, among which the most abundant modification is S-palmitoylation. Growing evidence has shown that this rivalrous pair of modifications, occurring in a reversible cycle, is essential for various biological functions. Aberrations in this process have been associated with various diseases, including cancer, neurological disorders, and immune diseases. This underscores the importance of studying enzymes involved in acylation and deacylation to gain further insights into disease pathogenesis and provide novel strategies for disease treatment. In this Review, we summarize our current understanding of the structure and physiological function of deacylases, highlighting their pivotal roles in pathology. Our aim is to provide insights for further clinical applications.


Assuntos
Neoplasias , Humanos , Animais , Neoplasias/enzimologia , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/genética , Aciltransferases/metabolismo , Aciltransferases/química , Doenças do Sistema Nervoso/enzimologia , Doenças do Sistema Nervoso/metabolismo , Acilação , Lipoilação , Processamento de Proteína Pós-Traducional , Doenças do Sistema Imunitário/enzimologia , Doenças do Sistema Imunitário/metabolismo
11.
J Pharmacol Exp Ther ; 389(2): 163-173, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38453527

RESUMO

Hepatocellular carcinoma (HCC) is the predominant pathologic type of primary liver cancer. It is a malignant tumor of liver epithelial cells. There are many ways to treat HCC, but the survival rate for HCC patients remains low. Therefore, understanding the underlying mechanisms by which HCC occurs and develops is critical to explore new therapeutic targets. Aldehyde dehydrogenase 2 (ALDH2) is an important player in the redox reaction of ethanol with endogenous aldehyde products released by lipid peroxidation. Increasing evidence suggests that ALDH2 is a crucial regulator of human tumor development, including HCC. Therefore, clarifying the relationship between ALDH2 and HCC is helpful for formulating rational treatment strategies. This review highlights the regulatory roles of ALDH2 in the development of HCC, elucidates the multiple potential mechanisms by which ALDH2 regulates the development of HCC, and summarizes the progress of research on ALDH2 gene polymorphisms and HCC susceptibility. Meanwhile, we envision viable strategies for targeting ALDH2 in the treatment of HCC SIGNIFICANCE STATEMENT: Numerous studies have aimed to explore novel therapeutic targets for HCC, and ALDH2 has been reported to be a critical regulator of HCC progression. This review discusses the functions, molecular mechanisms, and clinical significance of ALDH2 in the development of HCC and examines the prospects of ALDH2-based therapy for HCC.


Assuntos
Aldeído Oxirredutases , Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/genética , Aldeído Desidrogenase , Aldeído-Desidrogenase Mitocondrial/genética
12.
Opt Lett ; 49(5): 1169-1172, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38426965

RESUMO

The bound states in the continuum (BICs) have attracted much attention in designing metasurface due to their high Q-factor and effectiveness in suppressing radiational loss. Here we report on the realization of the third harmonic generation (THG) at a near-ultraviolet wavelength (343 nm) via accidental BICs in a metasurface. The absolute conversion efficiency of the THG reaches 1.13 × 10-5 at a lower peak pump intensity of 0.7 GW/cm2. This approach allows the generation of an unprecedentedly high nonlinear conversion efficiency with simple structures.

13.
BMC Cardiovasc Disord ; 24(1): 147, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448835

RESUMO

OBJECTIVE: Postoperative delirium is a common and debilitating complication that significantly affects patients and their families. The purpose of this study is to investigate whether there is an effective sedative that can prevent postoperative delirium while also examining the safety of using sedatives during the perioperative period. METHODS: The net-meta analysis was used to compare the incidence of postoperative delirium among four sedatives: sevoflurane, propofol, dexmedetomidine, and midazolam. Interventions were ranked according to their surface under the cumulative ranking curve (SUCRA). RESULTS: A total of 41 RCT studies involving 6679 patients were analyzed. Dexmedetomidine can effectively reduce the incidence of postoperative delirium than propofol (OR 0.47 95% CI 0.25-0.90), midazolam (OR 0.42 95% CI 0.17-1.00), normal saline (OR 0.42 95% CI 0.33-0.54) and sevoflurane (OR 0.39 95% CI 0.18-0.82). The saline group showed a significantly lower incidence of bradycardia compared to the group receiving dexmedetomidine (OR 0.55 95% CI 0.37-0.80). In cardiac surgery, midazolam (OR 3.34 95%CI 2.04-5.48) and normal saline (OR 2.27 95%CI 1.17-4.39) had a higher rate of postoperative delirium than dexmedetomidine, while in non-cardiac surgery, normal saline (OR 1.98 95%CI 1.44-2.71) was more susceptible to postoperative delirium than dexmedetomidine. CONCLUSION: Our analysis suggests that dexmedetomidine is an effective sedative in preventing postoperative delirium whether in cardiac surgery or non-cardiac surgery. The preventive effect of dexmedetomidine on postoperative delirium becomes more apparent with longer surgical and extubation times. However, it should be administered with caution as it was found to be associated with bradycardia.


Assuntos
Anestésicos , Delírio do Despertar , Hipnóticos e Sedativos , Humanos , Anestésicos/uso terapêutico , Bradicardia , Dexmedetomidina , Delírio do Despertar/prevenção & controle , Hipnóticos e Sedativos/uso terapêutico , Midazolam , Propofol , Solução Salina , Sevoflurano , Metanálise em Rede
14.
Front Cell Infect Microbiol ; 14: 1360880, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529472

RESUMO

Metal ions are essential trace elements for all living organisms and play critical catalytic, structural, and allosteric roles in many enzymes and transcription factors. Mycobacterium tuberculosis (MTB), as an intracellular pathogen, is usually found in host macrophages, where the bacterium can survive and replicate. One of the reasons why Tuberculosis (TB) is so difficult to eradicate is the continuous adaptation of its pathogen. It is capable of adapting to a wide range of harsh environmental stresses, including metal ion toxicity in the host macrophages. Altering the concentration of metal ions is the common host strategy to limit MTB replication and persistence. This review mainly focuses on transcriptional regulatory proteins in MTB that are involved in the regulation of metal ions such as iron, copper and zinc. The aim is to offer novel insights and strategies for screening targets for TB treatment, as well as for the development and design of new therapeutic interventions.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/metabolismo , Tuberculose/microbiologia , Metais/metabolismo , Homeostase/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Íons/metabolismo
15.
Materials (Basel) ; 17(6)2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38541527

RESUMO

Internal pore defects are inevitable during laser powder bed fusion (LPBF), which have a significant impact on the mechanical properties of the parts. Therefore, detecting pores and obtaining their morphology will contribute to the quality of LPBF parts. Currently, supervised models are used for defect image detection, which requires a large amount of LPBF sample data, image labeling, and computing power equipment during the training process, resulting in high detection costs. This study extensively collected LPBF sample data and proposed a method for pore defect classification by obtaining its morphological features while detecting pore defects in optical microscopy (OM) images under various conditions. Compared with other advanced models, the proposed method achieves better detection accuracy on pore defect datasets with limited data. In addition, quickly detecting pore defects in a large number of labeling ground truth images will also contribute to the development of deep learning. In terms of image segmentation, the average accuracy scores of this method in the test images exceed 85%. The research results indicate that the algorithm proposed in this paper is suitable for quickly and accurately identifying pore defects from optical microscopy images.

16.
Front Microbiol ; 15: 1329715, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357346

RESUMO

Mycobacterium tuberculosis (Mtb) is a bacterial pathogen that can endure for long periods in an infected patient, without causing disease. There are a number of virulence factors that increase its ability to invade the host. One of these factors is lipolytic enzymes, which play an important role in the pathogenic mechanism of Mtb. Bacterial lipolytic enzymes hydrolyze lipids in host cells, thereby releasing free fatty acids that are used as energy sources and building blocks for the synthesis of cell envelopes, in addition to regulating host immune responses. This review summarizes the relevant recent studies that used in vitro and in vivo models of infection, with particular emphasis on the virulence profile of lipolytic enzymes in Mtb. A better understanding of these enzymes will aid the development of new treatment strategies for TB. The recent work done that explored mycobacterial lipolytic enzymes and their involvement in virulence and pathogenicity was highlighted in this study. Lipolytic enzymes are expected to control Mtb and other intracellular pathogenic bacteria by targeting lipid metabolism. They are also potential candidates for the development of novel therapeutic agents.

17.
Cancer Med ; 13(3): e6736, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38204220

RESUMO

BACKGROUND: The mechanism of decreased T cells infiltrating tumor tissues in hepatocellular carcinoma is poorly understood. METHODS: Cells were separated from the single-cell RNA-sequence dataset of hepatocellular carcinoma patients (GSE149614) for cell-cell communication. Flow cytometry, EDU staining, H3-Ser28 staining, confocal immunofluorescence staining, western blotting and naked microsubcutaneous tumors were performed for the mechanism of NGF-NGFR promoting proliferation. RESULTS: The present study has revealed that during the process of T-cell infiltration from adjacent tissues to tumor tissues, an inefficiency in NGF-NGFR communication occurs in the tumor tissues. Importantly, NGF secreted by tumor cells interacts with NGFR present on the membranes of the infiltrated T cells, thereby promoting the proliferation through the activation of mitotic spindle signals. Mechanistically, the mediation of mitotic spindle signal activation promoting proliferation is executed by HDAC1-mediated inhibition of unclear trans-localization of PREX1. Furthermore, PD-1 mAb acts synergistically with the NGF-NGFR communication to suppress tumor progression in both mouse models and HCC patients. Additionally, NGF-NGFR communication was positively correlates with the PD-1/PDL-1 expression. However, expressions of NGF and NGFR are low in tumor tissues, which is responsible for the invasive clinicopathological features and the disappointing prognosis in HCC patients. CONCLUSION: Inefficiency in NGF-NGFR communication impairs PD-1 mAb immunotherapy and could thus be utilized as a novel therapeutic target in the treatment of HCC patients in clinical practice.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Humanos , Carcinoma Hepatocelular/terapia , Receptor de Morte Celular Programada 1 , Neoplasias Hepáticas/terapia , Linfócitos T , Imunoterapia , Fatores de Troca do Nucleotídeo Guanina , Proteínas do Tecido Nervoso , Receptores de Fator de Crescimento Neural
18.
Adv Mater ; 36(14): e2310438, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38165969

RESUMO

Surface nonlinear optics are essential for developments in integrated photonics and micro/nano optoelectronics. However, the nonlinear optical conversion efficiency on a surface is restricted by the finite nonlinear susceptibility of matter and the intrinsic atomic-layered interaction length between light and matter. In this work, based on an angular engineering strategy, it is demonstrated that the centrosymmetric topological semimetal HfGe0.92Te crystal has a giant and anisotropic surface second-order nonlinear susceptibility up to 5535 ± 308 pm V-1 and exhibits efficient and unprecedented second-harmonic generation (SHG). The maximum optical conversion efficiency is found to be up to 3.75‰, which is 104 times higher than that obtained from a silicon surface. Because of the linear dispersion over a wide range of energies around the Dirac points, this high conversion efficiency can be maintained with SHG wavelengths ranging from the visible region (779 nm) to the deep-UV region (257.5 nm). This study can facilitate the development of topological photonics and integrated nonlinear photonics based on topological semimetals.

19.
Opt Express ; 32(1): 959-968, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175116

RESUMO

Blue-laser-diode-pumped Pr3+-based continuous-wave (CW) green lasers have aroused growing research interest in developing optoelectronic applications and deep ultraviolet laser sources due to their simple and compact structural design. However, the obstacle of thermally induced effects limits the available output power of Pr3+-based green lasers. Herein, combined with the theoretical analysis and experimental feedback, we effectively adjust the heat distribution inside the Pr3+:LiYF4 gain crystal by optimizing the crystal dimension and doping concentration. The excellent mode matching between the pump and green lasers is achieved under the consideration of thermally induced effects, yielding a maximum CW output power of 7.56 W. To the best of our knowledge, this is the largest output power of Pr3+-based CW green lasers so far. Moreover, the obtained green laser demonstrates excellent output stability (RMS = 1.27%) and beam quality (M2 = 1.30 × 1.12) under the lasing operation state with the maximum output power. We hope that this study can provide a feasible paradigm for developing blue-laser-diode-pumped visible lasers, especially for high-power lasers.

20.
Adv Ther ; 41(1): 215-230, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37884809

RESUMO

INTRODUCTION: Exogenous gonadotropin (Gn) is given to regulate follicle-stimulating hormone (FSH) levels to achieve optimal ovarian response in in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). The objective of this study was to analyze the optimal degree of change in FSH blood concentration with ovarian responsiveness in a short-acting gonadotropin-releasing hormone agonist (GnRH-a) long protocol for IVF/ICSI. METHODS: This retrospective study was conducted at Changzhou Maternity and Child Health Hospital's Reproductive Center from May 2017 to May 2023. A total of 794 ovarian stimulation cycles for IVF/ICSI using the short-acting GnRH-a long protocol was included. Ovarian responsiveness was assessed based on the number of follicles > 14 mm on human chorionic gonadotropin (HCG) trigger day, refine-follicular output rate (Refine-FORT) and good quality embryos. Delta 1 referred to the change in FSH level between days 6-8 of gonadotropin usage and baseline FSH, while Delta 2 referred to the change in FSH level between HCG trigger day and days 6-8 of gonadotropin usage. Simple and multiple linear regression analysis were performed to adjust for confounding factors. RESULTS: The number of follicles > 14 mm on HCG trigger day was found to be the most suitable indicator for evaluating ovarian responsiveness compared to the number of follicles > 16 mm and the number of retrieved oocytes. When Delta 1 ranged from 1.94 to 3.37, the number of follicles > 14 mm on HCG trigger day was the highest. When Delta 1 ranged from 3.37 to 5.90, the Refine-FORT was the highest. However, when Delta 1 exceeded 5.90, the number of follicles > 14 mm on HCG trigger day, Refine-FORT and good quality embryo all significantly decreased. On the other hand, when Delta 2 was ≤ - 1.58, the number of follicles > 14 mm on HCG trigger day and the Refine-FORT were both the highest. CONCLUSION: This study identifies optimal Delta 1 and Delta 2 ranges for effective ovarian responsiveness in a short-acting GnRH-a long protocol for IVF/ICSI and introduces the novel measure of the number of follicles > 14 mm on HCG trigger day. The optimal range for Delta 1 was 1.94 to 3.37, and Delta 2 should be < - 1.58 for achieving a higher number and quality of oocytes.


Assuntos
Hormônio Liberador de Gonadotropina , Injeções de Esperma Intracitoplásmicas , Criança , Gravidez , Feminino , Masculino , Humanos , Injeções de Esperma Intracitoplásmicas/métodos , Estudos Retrospectivos , Taxa de Gravidez , Sêmen , Fertilização in vitro/métodos , Gonadotropina Coriônica , Indução da Ovulação/métodos , Hormônio Foliculoestimulante/uso terapêutico
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