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This study aimed to develop a longitudinal ultrasonic-assisted milling system to investigate the machinability of titanium (Ti) Alloy Ti-6Al-4V (TC4). Aiming at reduced milling force and enhanced surface quality, ultrasonic-assisted milling was investigated taking into account the following processing parameters: spindle speed (cutting rate) n, feed per tooth fz, milling depth ap, and ultrasonic amplitude A. A comparison was made with conventional milling. The results of univariate tests demonstrated that the ultrasonic amplitude had the most significant impact on the milling force along the z-axis, resulting in a reduction of 15.48% compared with conventional milling. The range analysis results of multivariate tests demonstrated that ap and fz were the dominant factors influencing the cutting force. The minimum reduction in the milling force in ultrasonic-assisted milling along the x-, y-, and z-axes was 11.77%, 15.52%, and 17.66%, respectively, compared with that in conventional milling. The ultrasonic-assisted milling led to reduced surface roughness and enhanced surface quality; the maximum surface roughness in ultrasonic-assisted milling was 25.93%, 36.36% and 26.32% in terms of n, fz, and ap, respectively. In longitudinal ultrasonic-assisted milling, the periodic "separation-contact" was accompanied by microimpacts, resulting in even smaller intermittent periodic cutting forces. Hence, regular fish scale machining mesh was observed on the processed surface, and the workpiece surface exhibited high cleanness and smoothness. The reasonable configuration of ultrasonic-assisted milling parameters can effectively improve the milling force and surface quality of Ti alloys and accumulate reference data for the subsequent machining process research.
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In a laboratory environment, in order to test the attitude recognition capability and accuracy of the satellite attitude sensor-the infrared Earth sensor-the infrared Earth simulator is fixed on a five-axis turntable to enable multi-angle testing. In the past, the temperature control system of the Earth simulator was water cooled, which not only affected the working accuracy of the Earth simulator but also affected its size and portability and made it more difficult to use on the turntable. Therefore, we designed a cooling method for the cold plate based on semiconductor cooling technology combined with air cooling, and we designed a fuzzy PID control algorithm to accurately control the temperature according to this cooling method. In this article, we use SOLIWORKS to build the system model for the system and use the ANAYS Workbench to perform temperature analysis of the Earth simulator. The results show that the cold plate temperature can be maintained at 20.089 °C when the hot plate temperature is 85 °C. The overall temperature uniformity of the hot plate is better than ±0.3 °C, which meets the index requirements of the Earth simulator. We found that this cooling method can replace water cooling, giving the simulator the advantage of being miniaturized, and it can be adaptable to the turntable, which can be widely used in various sizes of Earth simulators and in various complex environments and operating conditions.
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Despite numerous studies on Escherichia coli (E. coli) from sheep, there have been few reports on the characterization of E. coli isolates from various organs of individual sheep until now. The present study conducted molecular typing, antibiotics resistance, biofilm formation, and virulence genes on E. coli isolated from 57 freshly slaughtered apparently healthy sheep carcasses, gallbladders, fecal samples, and mesenteric lymph nodes (MLNs). The results demonstrated that the detection rate of R1 LPS core type in E. coli isolated from fecal samples (70.83%) was higher than that from other organs, but the detection rate of antibiotic resistance genes was lower (P < 0.05). The predominant phylogenetic group of E. coli isolated from the carcasses was group B1 (93.33%), and the detection rate of multidrug-resistance phenotype (80%) and the resistance rate of E. coli was higher than that from other organs (P < 0.05). Interestingly, the intensity of biofilm formation of E. coli isolated from MLNs was higher than that from other organs (P < 0.05). However, except for ibeB, the detection rates of virulence genes did not differ in E.coli isolated from different organs. In conclusion, differences were noted in these parameters of E. coli isolated from different organs of individual sheep. Therefore, the data may contain considerable mistakes concerning the actual situation in the host if we only analyze the data of E. coli isolated from feces or carcasses.
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This study conducted longitudinal ultrasonic-assisted milling (UAM) tests and optimized a combination of milling technological parameters to achieve high-quality machining of TC18 titanium alloy. The motion paths of the cutter under the coupled superposition states of longitudinal ultrasonic vibration and end milling were analyzed. Based on the orthogonal test, the cutting forces, cutting temperatures, residual stresses, and surface topographical patterns of TC18 specimens under different UAM conditions (cutting speeds, feeds per tooth, cutting depths, and ultrasonic vibration amplitudes) were examined. The differences between ordinary milling and UAM in terms of machining performance were compared. Using UAM, numerous characteristics (including variable cutting thickness in the cutting area, variable cutting front angles of the tool, and the lifting of the cuttings by the tool) were optimized, reducing the average cutting force in all directions, lowering the cutting temperature, increasing the surface residual compressive stress, and significantly improving the surface morphology. Finally, fish scale bionic microtextures with clear, uniform, and regular patterns were formed on the machined surface. High-frequency vibration can improve material removal convenience, thus reducing surface roughness. The introduction of longitudinal ultrasonic vibration to the end milling process can overcome the limitations of traditional processing. The optimal combination of UAM parameters for titanium alloy machining was determined through the end milling orthogonal test with compound ultrasonic vibration, which significantly improved the surface quality of TC18 workpieces. This study provides insightful reference data for subsequent machining process optimization.
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Objective: To summarize the use of Chinese Herbal Medicines (CHMs) for Idiopathic Pulmonary Fibrosis (IPF) and provide high-level evidence for clinical decisions. Methods: We analyzed systematic reviews (SRs). Two English-language and three Chinese-language electronic databases were searched from inception to July 1, 2019. Published SRs and meta-analyses evaluating CHM use in IPF and reporting clinically-relevant outcomes such as lung function, PO2, and quality of life were eligible for inclusion in this overview. The methodological qualities of the included SRs were assessed by AMSTAR and ROBIS tools. Results: All reviews were published from 2008 to 2019. 15SRs were published in Chinese-language while 2 were in English. A total of 15550 participants were included. All intervention arms received CHM with or without conventional treatment and were compared with control arms with conventional treatment alone, or hormone therapy. Twelve SRs were assessed with low risk of bias while five were assessed high risk by ROBIS. The quality of evidence was assessed to be "moderate" or "low" or "very low" using GRADE. Conclusions: CHM has potential benefits for patients with IPF especially in improving lung function (forced vital capacity (FVC), total lung capacity (TLC), and diffusing capacity of the lungs for carbon monoxide (DLCO)), PO2 level, and the quality of life of patients. Due to the low methodological quality of reviews, our findings should be interpreted with caution.
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Medicamentos Herbarios Chinos , Fibrosis Pulmonar Idiopática , Humanos , Medicamentos Herbarios Chinos/uso terapéutico , Fibrosis Pulmonar Idiopática/tratamiento farmacológico , Lenguaje , Calidad de Vida , Revisiones Sistemáticas como AsuntoRESUMEN
BACKGROUND: Brugada syndrome (BrS) is a genetic disorder characterized by a typical electrocardiogram pattern and predisposition to arrhythmias and sudden cardiac death. Despite our considerably evolved understanding of BrS, no bibliometrics have been performed in this research field. We aimed to analyze and visualize the characteristics of the scientific outputs, topical evolutions, and research trends of BrS over the past 2 decades using bibliometric analysis. METHODS: The literature associated with BrS was retrieved from the Science Citation Index Expanded of the Web of Science Core Collection database. Acquired data were then visually analyzed using CiteSpace and VOSviewer. RESULTS: 3042 qualifying records were included in the final analysis. The publication outputs increased over time. The United States was the leading country in the BrS research. The University of Amsterdam (Netherlands) was the most prolific and influential institution. Pedro Brugada, Arthur Wilde, and Charles Antzelevitch exerted notable publication impact and made the most significant contributions in the field of BrS. Heart Rhythm had the highest outputs and Circulation was the most influential journal. Bundle branch block, ST-segment elevation, mechanism, management, right precordial lead, and guideline were the keywords with the strongest citation burst. CONCLUSION: Research on BrS is prosperous. Keywords and co-citation analysis revealed that the mechanism, diagnosis, risk stratification, and management of BrS were the research hotspots. Besides, the underlying pathophysiology, novel therapies, and personalized risk assessment might be the emerging trends of future research.
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Síndrome de Brugada , Humanos , Bibliometría , Bloqueo de Rama , Trastorno del Sistema de Conducción Cardíaco , Bases de Datos FactualesRESUMEN
BACKGROUND: With the Coronavirus disease 2019 epidemic, wearing a mask has become routine to prevent and control the virus's spread, especially for healthcare workers. However, the impact of long-term mask wear on the human body has not been adequately investigated. This study aimed to investigate whether Powered Air Purifying Respirators and N95 masks impact the olfaction in healthcare workers. METHODS: We recruited fifty-six healthcare workers and randomly divided them into 2 groups, wearing a powered air purifying respirator (PAPR) (experiment group, N = 28) and an N95 mask (control group, N = 28). Olfactory discrimination and threshold tests were performed before and after wearing the masks. SPSS 26.0 (SPSS Inc., Chicago, Illinois) software was used for the statistical analyses. RESULTS: There was a statistical difference in the olfactory threshold test after wearing the mask in both PAPR Group (Z = -2.595, P = .009) and N95 Group (Z = -2.120, P = .034), with no significant difference between the 2 (χ2 = 0.29, P = .589). There was no statistical difference in the discrimination test scores in both 2 groups after wearing the masks. CONCLUSION: Wearing a mask affects the healthcare workers' olfaction, especially odor sensitivity. Healthcare workers have a higher olfactory threshold after long-term mask wear, whether wearing PAPRs or N95 masks.
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COVID-19 , Epidemias , Dispositivos de Protección Respiratoria , Humanos , Respiradores N95 , COVID-19/prevención & control , Personal de SaludRESUMEN
The cytokine storm plays an indispensable role in the severe and critical illness and death of the COVID-19 vulnerable population. Thus, suppressing the cytokine storm is of great significance. Ginseng is a traditional Chinese herb originally used for improving physiological conditions and ameliorating disease. Common throughout the history of ancient Chinese medicine is utilizing ginseng as a major ingredient to successfully fight various pandemics, and the most famous decoction is Renshen Baidu powder. In recent years, ginseng has been observed to provide preventive and therapeutic benefits in the treatment of various conditions by suppressing hyper-inflammation, inhibiting virus intrusion, and balancing the host's immunity. This paper summarizes the ancient Chinese medicine books' recordings of, the clinical practice of, and the laboratory exploration of ginseng for the treatment of pandemics and COVID-19. Ginseng and its active ingredients were found to downregulate inflammatory cytokines, upregulate anti-inflammatory cytokines, stimulate the secretion of the antiviral cytokine IFN-[Formula: see text], prevent viral entry and replication, and improve viral clearance. Furthermore, ginseng modulates both natural and acquired immunity during viral infection. Collectively, we propose that ginseng can act as a key immune response modulator against the cytokine storm of COVID-19. This paper may provide a new approach to discover specific medications using ginseng to combat COVID-19.
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COVID-19 , Panax , Humanos , SARS-CoV-2 , Medicina Tradicional China , Síndrome de Liberación de Citoquinas/tratamiento farmacológico , Citocinas , InmunidadRESUMEN
We aimed to identify the relationship between variations in metabolic genes and human urinary changes in mercapturic acids (MAs), including CEMA, HMPMA, SPMA, HPMA and HEMA, before and after air pollution exposure. Genotype detection for 47 relevant single nucleotide polymorphisms (SNPs) collected by literature research was performed. Five MAs expression levels in the urinary samples of 50 young healthy individuals with short-term exposure to clean, polluted and purified air at five time points were detected by targeted online solid-phase extraction liquid chromatography tandem mass spectrometry (SPE-LC-MS/MS), followed with associations of SNPs with MAs changes. Difference in MAs between polluted and clean/purified air was significantly associated with 21 SNPs mapped into 9 genes. Five SNPs in GSTP1 showed the most prominent association with the changes in SPMA expression, indicating that those SNPs in GSTP1 and SPMA might serve as biomarkers for susceptibility and the prognosis of lung cancer.
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Acetilcisteína , Contaminación del Aire , Humanos , Cromatografía Liquida/métodos , Voluntarios Sanos , Espectrometría de Masas en Tándem/métodos , Polimorfismo Genético , BiomarcadoresRESUMEN
BACKGROUND: Wiskott-Aldrich syndrome (WAS) is a rare X-linked primary immunodeficiency disorder. Despite our enormous progress in the strategies used to diagnose, treat, and cure WAS, no bibliometric studies have been performed in this research field. This study explored the trends in WAS research through a bibliometric analysis evaluating relevant literature quantitatively and qualitatively. METHODS: The literature concerning WAS from 2001 to 2021 was retrieved from the Science Citation Index Expanded (SCI-expanded) of the Web of Science Core Collection database. Acquired data were then visually analyzed using CiteSpace and VOSviewer. RESULTS: 2036 papers were included in the final analysis. The annual publication outputs reached its peak in 2013 but declined in recent years. The dominant position of the United States in WAS research was quite obvious. Harvard University (USA), University College London (UK), and Inserm (France) were the three most prolific institutions. Adrian J. Thrasher exerted significant publication impact and made the most notable contributions in the field of WAS. Blood was the most influential journal with the highest publication outputs, and nearly all the top 10 journals and co-cited journals belonged to Q1. Immune dysregulation, thrombocytopenia, syndrome protein deficiency, stem cell, mutation, and diagnosis were the keywords with the strongest citation burst. CONCLUSION: From 2001 to 2021, the United States was a global leader in the WAS research. Collaboration between countries and institutions is expected to deepen and strengthen in the future. Research hotspots included pathogenesis, clinical manifestations, diagnosis, and therapy. Our results suggest a greater understanding of the mechanistic underpinnings of immune dysfunction in WAS patients, the application of targeted therapies for individual complications, and the development of curative approaches, which will remain research hotspots in the future.
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Trombocitopenia , Síndrome de Wiskott-Aldrich , Humanos , Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/terapia , Bibliometría , Bases de Datos Factuales , FranciaRESUMEN
Background: Danlou tablet (DLT), the traditional Chinese medicine has been commonly used for dyslipidemia, atherosclerosis, and coronary heart disease. Whether it was effective against vascular injury caused by CIH has remained unknown. The aim of the current study was to observe the effects of DLT on chronic intermittent hypoxia (CIH)-induced vascular injury via regulation of blood lipids and to explore potential mechanisms. Methods: Sixteen 12-week-old male ApoE-/- mice were randomly divided into four groups. The sham group was exposed to normal room air, whereas the other three groups were exposed to CIH. Mice in the CIH + normal saline (NS) group were gavaged with NS. Mice in the CIH + Angptl4-ab group were intraperitoneally injected with Angptl4-antibody. Mice in the CIH + DLT group were gavaged with DLT. After four weeks of intervention, serum lipid concentrations, and serum lipoprotein lipase (LPL) activity were detected. The changes in atherosclerosis in vascular tissue were detected by hematoxylin and eosin (H&E) staining. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis were applied to detect the expression levels of hypoxia-induciblefactor-1 (HIF-1), factor-inhibiting HIF-1 (FIH-1), angiopoietin-like 4 (Angptl4), and LPL in different tissues. Results: CIH exposure increases serum lipid levels, decreases serum LPL activity, and exacerbates atherosclerosis. Both Angptl4-ab and DLT treatment reversed the changes in lipid concentration, LPL activity, and atherosclerosis caused by CIH. In the epididymal fat pad, CIH exposure decreased the expression of FIH-1 and increased the expression of HIF-1, whereas DLT treatment increased the expression of FIH-1 and LPL and inhibited the expression of HIF-1 and Angptl4. In heart tissue, the expression levels of LPL and Angptl4 were not affected by modeling or treatment. Conclusions: DLT improved vascular damage by improving the increase in blood lipids induced by CIH, potentially by upregulating FIH-1 and downregulating HIF-1 and Angptl4 in adipose tissue. Therefore, DLT may be a promising agent for the prevention and treatment of CIH-induced vascular injury.
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The detection of phytohormones in real time has attracted increasing attention because of their critical roles in regulating the development and signaling of plants, especially in defense against biotic stresses. Herein, stainless steel sheet electrodes modified with carbon cement were coupled with paper-based analysis devices for direct and simultaneous detection of salicylic acid (SA) and indole-3-acetic acid (IAA) in plants. We demonstrated that the excellent conductivity of stainless steel sheet electrodes enabled us to simultaneously differentiate IAA and SA at a level of 10 nM. With our approach, the content of IAA and SA in Arabidopsis thaliana leaves infected or not infected with Pst DC3000 could be rapidly quantified at the same time. Our experimental results on differentiation of IAA and SA at different time points showed that there were antagonistic interactions between the IAA and SA after infection of Arabidopsis leaves with Pst DC3000. By offering a cost-effective approach for rapid and sensitive detection of IAA and SA, this study suggests that electrochemical detection can be used in the study and development of precision agriculture technology.
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Proteínas de Arabidopsis , Arabidopsis , Ácido Salicílico/farmacología , Acero Inoxidable , Reguladores del Crecimiento de las Plantas , Proteínas de Arabidopsis/farmacología , Pseudomonas syringae/fisiología , Ácidos Indolacéticos , Electrodos , Estrés Fisiológico , Carbono/farmacología , Enfermedades de las PlantasRESUMEN
Objective: This study aims to explore the effect of integrating routine treatment with Tai Chi Chuan (TCC) intervention on the clinical symptom of patients with Chronic Obstructive Pulmonary Disease (COPD) from clinical and neurological perspectives. Methods: Twenty patients with COPD were recruited for regular treatment combined with 8-week TCC rehabilitative practice. Clinical symptoms were evaluated by Chronic Obstructive Pulmonary Symptom Assessment Scale (CAT) and Modified Dyspnea Scale (mMRC) at baseline and after treatment. Resting-state MRI scan was also performed with multiline T2-weighted echo-planar imaging (EPI) to acquire their functional images before and after the treatment. TCC rehabilitation involved a total of 8 weeks of practice with 90 min per session, three times a week. Results: After an 8-week integration routine treatment with TCC practice, the patient's clinical symptoms improved significantly. Imaging analysis showed that COPD patients exhibited decreased Degree of Centrality (DC) in the right inferior frontal gyrus (IFG), right middle frontal gyrus, bilateral cingulate cortex, bilateral precuneus, and right precentral gyrus. Moreover, correlation analysis found that the decreased DC in the right IFG was positively correlated with the CAT improvements. Conclusion: The routine treatment involving TCC rehabilitation practice could improve the clinical symptoms of patients with COPD. The right IFG might be a key brain region to contribute to the neural mechanism underlying integrative intervention on the clinical symptoms in COPD. These findings provide neurological evidence for treating COPD rehabilitation practice with mind-body practice based on Chinese culture to some extent, which also advances the understanding of the efficacy of TCC as the adjuvant technology from a neuroscience perspective. Clinical Trial Registration: [http://www.chictr.org.cn/showproj.aspx?proj=45189], identifier [ChiCTR1900028335].
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With the in-depth advancement of the fifth generation (5G) mobile communication technology, the technical requirements for filters are also constantly improving. Surface acoustic wave (SAW) filters are widely used in home TV, mobile communications, radio frequency filters and radar due to their simple structure, few mask layers, easy miniaturization, and low cost. Through the continuous improvement of communication technology, SAW has developed into various high-performance acoustic filters from bulk SAW with the support of some new architectures, new materials and advanced modeling techniques. This paper analyzes and reviews the research situation of SAW filter technology.
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Numerous epidemiological studies have shown a close relationship between outdoor air pollution and increased risks for cancer, infection, and cardiopulmonary diseases. However, very few studies have investigated the potential health effects of coexposure to airborne particulate matter (PM) and bioaerosols through the transmission of infectious agents, particularly under the current circumstances of the coronavirus disease 2019 pandemic. In this study, we aimed to identify urinary metabolite biomarkers that might serve as clinically predictive or diagnostic standards for relevant diseases in a real-time manner. We performed an unbiased gas/liquid chromatography-mass spectroscopy (GC/LC-MS) approach to detect urinary metabolites in 92 samples from young healthy individuals collected at three different time points after exposure to clean air, polluted ambient, or purified air, as well as two additional time points after air repollution or repurification. Subsequently, we compared the metabolomic profiles between the two time points using an integrated analysis, along with Kyoto Encyclopedia of Genes and Genomes-enriched pathway and time-series analysis. We identified 33 and 155 differential metabolites (DMs) associated with PM and bioaerosol exposure using GC/LC-MS and follow-up analyses, respectively. Our findings suggest that 16-dehydroprogesterone and 4-hydroxyphenylethanol in urine samples may serve as potential biomarkers to predict or diagnose PM- or bioaerosol-related diseases, respectively. The results indicated apparent differences between PM- and bioaerosol-associated DMs at five different time points and revealed dynamic alterations in the urinary metabolic profiles of young healthy humans with cyclic exposure to clean and polluted air environments. Our findings will help in investigating the detrimental health effects of short-term coexposure to airborne PM and bioaerosols in a real-time manner and improve clinically predictive or diagnostic strategies for preventing air pollution-related diseases.
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Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Biomarcadores/análisis , Humanos , Material Particulado/análisis , Adulto JovenRESUMEN
INTRODUCTION: Pulmonary alveolar proteinosis (PAP) is an ultrarare disorder characterised by the accumulation of alveolar surfactant and the dysfunction of alveolar macrophages that results in hypoxemic respiratory failure. Whole-lung lavage (WLL) is currently the primary therapy for PAP. However, systematic evaluation of the clinical efficacy of WLL is lacking. We aim to perform a systematic review and meta-analysis of existing evidence to support WLL for the clinical treatment of PAP. METHODS AND ANALYSIS: We will search the PubMed (MEDLINE), Cochrane Library, Embase, Web of Science and Google Scholar databases from inception to December 2021 for observational studies using WLL for the treatment of PAP. Two authors will independently screen the eligible studies, assess the quality of the included papers and extract the required information. Review Manager V.5.4 will be used to perform the meta-analysis. We will evaluate the overall quality of evidence using the Grading of Recommendations, Assessment, Development and Evaluation approach. All steps of this protocol will be performed using the Cochrane Handbook for Preferred Reporting Items for Systematic Review and Meta-analysis statement. ETHICS AND DISSEMINATION: This systematic review and meta-analysis will be based on published data. Therefore, ethical approval is not required. We will publish our results in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42022306221 (https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022306221).
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Proteinosis Alveolar Pulmonar , Insuficiencia Respiratoria , Lavado Broncoalveolar/métodos , Humanos , Metaanálisis como Asunto , Proteinosis Alveolar Pulmonar/terapia , Revisiones Sistemáticas como AsuntoRESUMEN
Background: Pulmonary alveolar proteinosis (PAP) is a rare syndrome first described by Rosen et al. in 1958. Despite our considerably evolved understanding of PAP over the past decades, no bibliometric studies have been reported on this field. We aimed to analyze and visualize the research hotspots and current trends of the PAP research field using a bibliometric analysis to help understand the future development of basic and clinical research. Methods: The literature regarding PAP was culled from the Web of Science Core Collection (WoSCC) database. Data were extracted from the relevant articles and visually analyzed using CiteSpace and VOSviewer software. Results: Nine hundred and nine qualifying articles were included in the analysis. Publications regarding PAP increased over time. These articles mainly come from 407 institutions of 57 countries. The leading countries were the USA and Japan. University of Cincinnati (USA) and Niigata University (Japan) featured the highest number of publications among all institutions. Bruce C Trapnell exerts a significant publication impact and has made the most outstanding contributions in the field of PAP. American Journal of Physiology-Lung Cellular and Molecular Physiology was the journal with the most publications, and American Journal of Respiratory and Critical Care Medicine was the most commonly cited journal. All the top 5 co-cited journals belong to Q1. Keyword citation bursts revealed that inflammation, deficiency, tissue resident macrophage, classification, autoimmune pulmonary alveolar proteinosis, sarcoidosis, gm csf, high resolution ct, and fetal monocyte were the emerging research hotspots. Conclusion: Research on PAP is prosperous. International cooperation is also expected to deepen and strengthen in the future. Our results indicated that the etiology and pathogenesis of PAP, current and emerging therapies, especially the novel pathogenesis-based options will remain research hotspots in the future.
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To achieve high-quality machining of the 2195 aluminum-lithium alloy, this paper presents an experimental study on the effect of milling processing parameters on milling forces and surface topography, during which conventional milling and longitudinal-torsional ultrasonic vibration milling of the 2195 Al-Li alloy were performed. The characterization of the tool tip trajectory illustrates some of the advantages of ultrasonic machining, which include variable depth of cut and tool chip pulling. The differences in milling forces between conventional milling and longitudinal-torsional ultrasonic vibration machining were compared using orthogonal tests, and the effect of ultrasonic vibration on milling forces was investigated in detail. The maximum reduction of milling force Fy in the feed direction under the influence of torsional vibration is 62% and 54% for larger feed per tooth and cutting depth, respectively. The high-frequency impact generated by the longitudinal vibration not only reduces the chip accumulation on the surface, but also smooths out the tool-tooth scratches and creates a regular surface profile. In addition, the characteristics of the milling force signals of the two machining methods were analyzed, and the analysis of the spectrum of the collected milling forces revealed that the ultrasonic vibration caused the high-frequency components of the milling forces Fy and Fz. The orthogonal result analysis and single-factor result analysis verified the superiority of ultrasonic machining, provided parameter selection for subsequent aluminum-lithium alloy machining, and bridged the gap of longitudinal torsional ultrasonic vibration machining of 2195 aluminum-lithium alloy in the study of milling force.
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Background: Birt-Hogg-Dubé syndrome (BHD) is a rare autosomal dominant inherited disorder caused by germline mutations in folliculin (FLCN). Despite our significantly evolved understanding of BHD over the past decades, no bibliometric analyses have been conducted in this field. This study aimed to analyze and visualize the characteristics of publication outputs, the research hotspots, and scientific frontiers about BHD using bibliometric analysis. Methods: All relevant literature on BHD was culled from the Web of Science Core Collection (WoSCC) database. Valid data were extracted from the articles and visually analyzed using CiteSpace and VOSviewer. Results: A total of 751 qualifying papers were included. Publication outputs concerning BHD increased over time. The dominant position of the United States and Japan in BHD research field was evident. National Cancer Institute (the USA) and Yokohama City University (Japan) were the two most productive organizations. W. Marston Linehan exerted a considerable publication impact and had made the most remarkable contributions in the field of BHD. Plos One was the journal with the highest publication outputs, and half of the top 10 journals and co-cited journals belonged to Q1 or Q2. Keyword citation bursts revealed that management, tumor suppressor, flcn gene, spectrum, diagnosis, risk, computed tomography were the emerging research hotspots. Conclusion: Research on BHD is prosperous. International cooperation between countries and organizations is also expected to deepen and strengthen in the future. Our results indicated that FLCN-associated pathways involved in the pathogenesis of BHD, specific options for early diagnosis, and molecular-targeting therapies will remain research hotspots in the future.