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IllustrisTNG Insights: Factors Affecting the Presence of Bars in Disk Galaxies
Get PDFBars are important in the secular evolution of galaxies. This study is aimed at exploring the reasons why some galaxies have bars at redshift z=0 while others do not. We use ellipse fitting to measure the properties and evolution of bars in the IllustrisTNG cosmological simulation. By using the K-S two-sample test and tracing their evolutionary changes, we analyze the parameter differences between barred and unbarred galaxies. The properties of galaxies with short bars are also studied. When tracing all disk galaxies at z=0 back to z=1, all of them show similar bar features at z=1. The fraction of bars increases in barred and short-bar galaxies but decreases in unbarred galaxies during z=1−0. In the case of disk galaxies with stellar mass log(M∗/M⊙)>10.8, nurture (mainly mergers) plays the most important role in suppressing or destroying bars. Bars are more likely to endure in galaxies that experience fewer mergers, which can be quantified by smaller stellar halos and ex-situ mass fractions. Approximately 60\% of the unbarred galaxies in the local Universe once had a bar. In contrast, the lack of responsiveness to bar instabilities (a larger Toomre-Q parameter) due to a less compact nature plays an important role in generating unbarred disk galaxies with stellar mass log(M∗/M⊙)<10.8. Moreover, short bars generally form at a similar time to normal bars, during which they either grow mildly or contract significantly. The fact that IllustrisTNG simulations may produce too many short-bar galaxies indicates that the dynamical properties of the central regions in IllustrisTNG galaxies are less likely to be affected by external factors, such as mergers and gas inflows
Metastatic basal cell carcinomas in Gorlin syndrome—A case series and literature review
No full textMetastatic basal cell carcinomas (mBCCs) are exceedingly rare, with an estimated variable prevalence rate between 0.003 and 0.55% among all basal cell carcinomas. Although there are hundreds of reported cases of mBCCs, a dearth of evidence exists of mBCCs in patients with Gorlin syndrome—an autosomal dominant genetic disorder. The purpose of this article was to present the first and largest case series of patients with mBCC in Gorlin. A literature review (LR) compares our data with the existing evidence base to underscore the importance of early surveillance, diagnosis and surgical intervention of suspicious lesions as distant metastases significantly reduce survival rates
A systematic assessment of the stability of SLA® vs. SLActive® implant surfaces over 12 weeks
Get PDFObjective
This study aims to assess the impact of two implant surfaces, SLA and SLActive, on implant stability, measured by ISQ levels over a 12-week period.
Methods
A comprehensive search of MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Dentistry and Oral Sciences databases for randomized controlled trials (RCTs) up to February 2023 was conducted. The inclusion criteria were studies involving adult patients treated with SLA and SLActive implants, with assessment of implant stability through ISQ levels up to 12 weeks post-placement.
Results
From the initial 180 potentially eligible publications identified, six RCTs were included in our analysis, comprising 326 implants (50.6% SLA and 49.4% SLActive). Three studies were classified as low risk, while three had an unclear risk of bias. Overall, SLActive implants demonstrated comparable stability levels, as measured by ISQ, to SLA implants within the 12-week interval for implants placed in the maxillary or mandibular region. However, findings from the RCTs suggest that the SLActive surface led to an earlier transition point, a faster return to stability levels, and higher ISQ values at the end of 12 weeks compared to the SLA surface for implants placed in the palatal region.
Conclusion
SLActive surfaces exhibited stability levels similar to SLA surfaces for maxillary and mandibular implants. Notably, for palatal implants, SLActive resulted in a quicker transition point and higher stability levels at the 12-week mark. Due to the limited number of trials and potential study heterogeneity, further research is needed to validate these findings
Taylor dispersion analysis as a tool for size measurement of PAMAM dendrimers: the effect of generation, functionality and pH
Get PDFTaylor Dispersion Analysis (TDA) is explored to measure the hydrodynamic sizes of full and half generation PAMAM dendrimers up to generation 4.5 in various buffer solutions. A method was used to minimize the interaction between the capillary and cationic dendrimers. The effects of generation, surface functionality, pH and ionic strength on the hydrodynamic radii of PAMAM dendrimers were investigated. Our results show that TDA can accurately measure the sizes of PAMAM dendrimers with a relatively low standard deviation especially for half generations. It was found that the ionisation of functional groups at various pH values led to a conformational change due to electrostatic repulsion or back-folding of the branches. Furthermore, adding salt to a half-generation dendrimer (G4.5) can lead to a profound size change that is dependent on ionic strength. A 17% increase in the size of the G4.5 dendrimer was observed in a 1 M NaCl solution compared to that in a 0.1 M solution. Compared to dynamic light scattering, TDA is more reliable and tolerant to large particles in the solutions. The findings of this study indicate that TDA could serve as a viable alternative technique for assessing dendrimer size and conformation, as well as studying their binding behavior
Liberty, the Maria Luz Incident and the Liminal Legal Status of Chinese Indentured Labourers and Japanese Licensed Prostitutes
No full textWhile covering the same ground as recent scholarship on the emancipatory potential of the Maria Luz incident, this article takes a radical departure, arguing that the background to the incident was British desire to disrupt the Macao trade in Chinese labour to Peru; that the legal focus of the ad hoc tribunals was not on any nascent human right to free the Chinese men and minors from being trafficked to Peru but on who owned and controlled their labour; and that the release of Japanese licensed prostitutes from their contracts was an unintended consequence of the legal fiction that the Japanese legal system was comparable with the principles of British common law
The Rise of Dark Kitchens: Characteristics and Operational Challenges
Get PDFThe dark kitchen model has gained popularity in recent years, with many choosing this model over traditional dine-in restaurants or takeaways. Despite its popularity, there remain limited studies on this type of food business operating model. This study aims to investigate why food business operators choose to adopt the dark kitchen model and the lessons learned from their operational experiences. An online survey was conducted among 123 Environmental Health Officers (EHOs) based in Local Authorities in England. Sixteen semi-structured interviews with dark kitchens were conducted of which 12 were dark kitchen tenants and 4 dark kitchen owners. The primary reasons for choosing this model include affordability, flexibility, and convenience. Social media platforms and online aggregators are essential for dark kitchens to advertise their food. However, some inconsistencies between different online aggregators occur when onboarding. A key issue raised by participants were the challenges of managing food safety and hygiene practices in shared spaces where several food businesses utilise the same space or resources. Other challenges faced when operating the dark kitchen model include competition, dependence on online aggregators, commission fees, and lack of visibility. In conclusion, the dark kitchen model presents both advantages and challenges for dark kitchen operators. While it offers cost-effectiveness, flexibility, and convenience, it also presents its own set of challenges. The operational challenges identified in this study offer practical implications and lessons learnt from dark kitchens’ previous experiences of starting a delivery-only food business. The challenges outlined should be considered by
policymakers, online aggregators and dark kitchens to support the development of more comprehensive guidelines and standardised practice
Correction: Historical context and drivers of forest cover change in wayanad plateau: a key elephant landscape in India’s Western Ghats
No full textP332: Oncological Safety and Patient Satisfaction of Immediate Lipofilling in Breast-Conserving Surgery: A Systematic Reviewand Subgroup Meta-Analysis Comparing Outcomes with No Lipofilling
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Commentary on: Inspiratory Muscle Training, with or without Pulmonary Rehabilitation, for COPD: A Critical Appraisal of a Cochrane Review
Get PDFApproximately 300 million people worldwide have COPD (1) with a global prevalence of between approximately 10-12.2% (2-4). COPD is a highly prevalent respiratory disease in the United Kingdom, ranking as the second most common lung disease, with approximately 1.2 million people diagnosed (5).
In COPD, oxidative stress and sarcomere injury lead to proteolysis and subsequent atrophy of the diaphragm, the main inspiratory muscle (6). The reduction in capacity of the respiratory muscles lead to a reduction in the body’s capacity to generate inspiratory pressures, thus reducing lung capacity and is thought to contribute to dyspnoea in adults with advanced COPD (7).
Respiratory muscle weakness is a modifiable weakness and can be targeted with interventions including variations in frequency and duration of Inspiratory Muscle Training (IMT) (8). Inspiratory muscle training uses resistance to challenge inhalation, stimulating respiratory muscles and potentially enhancing contractile force through hypertrophy (9). A previous Cochrane review examined the effectiveness of IMT, both with and without pulmonary rehabilitation, in increasing inspiratory muscle strength in individuals with COPD (10)