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Label-Free Visualization and Segmentation of Endothelial Cell Mitochondria Using Holotomographic Microscopy and U-Net
Get PDFUnderstanding the physiological processes underlying cardiovascular disease (CVD) requires examination of endothelial cell (EC) mitochondrial networks, because mitochondrial function and adenosine triphosphate production are crucial in EC metabolism, and consequently influence CVD progression. Although current biochemical assays and immunofluorescence microscopy can reveal how mitochondrial function influences cellular metabolism, they cannot achieve live observation and tracking changes in mitochondrial networks through fusion and fission events. Holotomographic microscopy (HTM) has emerged as a promising technique for real-time, label-free visualization of ECs and their organelles, such as mitochondria. This nondestructive, noninterfering live cell imaging method offers unprecedented opportunities to observe mitochondrial network dynamics. However, because existing image processing tools based on immunofluorescence microscopy techniques are incompatible with HTM images, a machine-learning model is required. Here, we developed a model using a U-net learner with a Resnet18 encoder to identify four classes within HTM images: mitochondrial networks, cell borders, ECs, and background. This method accurately identifies mitochondrial structures and positions. With high accuracy and similarity metrics, the output image successfully provides visualization of mitochondrial networks within HTM images of ECs. This approach enables the study of mitochondrial networks and their effects, and holds promise in advancing understanding of CVD mechanisms
Layover start timing predicts layover sleep quantity and timing on long-range and ultra-long-range trips
Get PDFStudy Objectives: Airline transport pilot sleep during layover is an important factor for alertness on subsequent flights. Assessing pilots\u27 sleep on layover is an important first step in helping them obtain the most recuperative sleep possible on layover. Here, we investigate the quantity and timing of sleep during layovers and determine predictors for layover sleep. Methods: Sleep was assessed in 256 pilots flying a total of 473 long-range (LR; flight time 12-16 hours) or ultra-long-range (ULR; flight time \u3e 16 hours) trips. Sleep was assessed using actigraphy. We employed linear mixed-effects models with layover sleep characteristics as the outcomes. The predictor variables included operational factors and sleep history. Results: Overall, pilots averaged 7.2 hours of sleep per 24 hours of layover, which was significantly less than their daily sleep before or after the trip. Layover start time (relative to home base time) was the most salient predictor of sleep timing and quantity during both shorter (∼24-hour) and the first 24 hours of longer (∼48-hour) layovers. During the last 24 hours of longer layovers, crew type predicted sleep quantity. Conclusions: Although average sleep quantity during layovers was within the margins of recommended sleep duration, it was still less than pre- and post-trip sleep duration, suggesting modest sleep loss on layovers. Layover start timing was the strongest predictor of layover sleep quantity and timing and, thus, may be a modifiable factor to protect circadian-aligned sleep opportunities during layover
Using a Sober Curious Framework to Explore Barriers and Facilitators to Helping Sexual Minority Women Reduce Alcohol-Related Harms: Protocol for a Descriptive Study
Get PDFBackground: Globally, women consume less alcohol than men, but alcohol consumption among women has declined less in recent years than among men. Drinking rates and alcohol-related harms vary substantially across population groups of women, and sexual minority women (eg, lesbian, bisexual, and queer) are at notably high risk. An emerging body of literature suggests that in addition to minority stress (eg, stigma, discrimination), drinking norms and drinking cultures likely influence sexual minority women’s drinking. Almost no research has explored these factors as possible targets of interventions. Sober curiosity is a rapidly growing wellness movement that may be particularly salient for sexual minority women. It encourages individuals to be “curious” about the reasons they choose to drink and alcohol’s effects on their life and health. Objective: The aims of this research are to (1) explore the perspectives of the drinking social worlds of sexual minority women, their awareness of the sober curious movement, perceptions of their own and their peers’ drinking and desire to drink less, and perceived barriers and facilitations to changing their drinking behaviors and (2) identify key elements of an alcohol reduction intervention tailored for sexual minority women. Methods: We conducted a comprehensive review of the literature on alcohol interventions with sexual minority women. The handful of studies we found paid scant attention to drinking cultures, normative beliefs, or other key elements of sober curiosity. To address the study aims, we are conducting 2 descriptive studies with adult (\u3e18 years) sexual minority women using mixed methods. One includes focus group interviews (n=24-36) and a national survey (n=100-120) with sexual minority women in Scotland. The other includes in-depth interviews (n=18-20) with sexual minority women in the United States. Data from the 2 countries and 3 sources will be analyzed using qualitative and quantitative methods to identify patterns and relationships across data to validate or corroborate findings. Results: Each of the studies received ethics approval in August 2023 and is currently open for recruitment. We anticipate completing data collection in spring 2025. The results of qualitative analyses will be summarized as themes, and results of survey data analyses will be summarized in tables. Findings will be presented to 2 panels of international experts who will assist in identifying critical elements of an alcohol reduction intervention tailored to the unique needs of sexual minority women. Conclusions: With the assistance of the expert panels, we will use Acceptability, Practicability, Effectiveness, Affordability, Side-Effects, and Equity criteria to inform the development of a tailored intervention building on tenants of sober curiosity to assist sexual minority women in reducing harmful drinking
New Zealand Security Agencies’ Secrecy, Accountability, and Transparency in the Modern Era
Get PDFNew Zealand’s security agencies need to balance conflicting missions of secrecy, accountability, and transparency in conducting national security government operations. Citizens expect protection without violating their liberties and for security agencies to act effectively and legally. From public revelations about the agencies and government reform efforts, the agencies evolved from almost total secrecy to greater accountability and transparency since World War II. This study employs a historical methodology, which examines primary source documents to reveal the history of secret behavior and to reform the New Zealand Security Intelligence Service and the Government Communications Security Bureau
Creative Commons Reboot of the FOSIL-based Heroic Inquiry Cycle
Get PDFThis brief multimedia article discusses the Creative Commons reboot of FOSIL-based Heroic Inquiry in two parts. The first part is a written reflection by Darryl Toerien on the collaborative development of Heroic Inquiry (1.x) at Blanchelande College in 2021, which is the alignment of the stages in the FOSIL-based inquiry process (2010) with the stages in the Hero\u27s Journey, and then the reasons for the collaborative redevelopment of Heroic Inquiry (2.x) for the FOSIL Symposium in 2025. The second part is a recorded reflection by Hugh Rose on his visual interpretation of the design brief for Heroic Inquiry (2.x)
Spartan Daily, February 11, 2025
Get PDFVolume 164, Issue 8https://scholarworks.sjsu.edu/spartan_daily_2025/1007/thumbnail.jp
Leveraging Diverse Knowledge to Support Collection Development: Maximizing Student Engagement and Community Resource Value in Varied Community College Settings
Get PDFSpartan Daily, February 19, 2025
Get PDFVolume 164, Issue 12https://scholarworks.sjsu.edu/spartan_daily_2025/1011/thumbnail.jp
Differential encoding of mammalian proprioception by voltage-gated sodium channels
Get PDFAnimals requiring purposeful movement for survival are endowed with mechanoreceptors, called proprioceptors, that provide essential sensory feedback from muscles and joints to spinal cord circuits, which modulates motor output. Despite the essential nature of proprioceptive signaling in daily life, the mechanisms governing proprioceptor activity are poorly understood. Here, we identified nonredundant roles for two voltage-gated sodium channels (NaVs), NaV1.1 and NaV1.6, in mammalian proprioception. Deletion of NaV1.6 in somatosensory neurons (NaV1.6cKO mice) causes severe motor deficits accompanied by loss of proprioceptive transmission, which contrasts with our previous findings using similar mouse models to target NaV1.1 (NaV1.1cKO). In NaV1.6cKO animals, we observed impairments in proprioceptor end-organ structure and a marked reduction in skeletal muscle myofiber size that were absent in NaV1.1cKO mice. We attribute the differential contributions of NaV1.1 and NaV1.6 to distinct cellular localization patterns. Collectively, we provide evidence that NaVs uniquely shape neural signaling within a somatosensory modality
Dynamic Imprints of Colliding-wind Dust Formation from WR 140
Get PDFCarbon-rich Wolf-Rayet (WR) binaries are a prominent source of carbonaceous dust that contribute to the dust budget of galaxies. The “textbook” example of an episodic dust-producing WR binary, WR 140 (HD 193793), provides us with an ideal laboratory for investigating the dust physics and kinematics in an extreme environment. This study is among the first to utilize two separate JWST observations, from Cycle 1 ERS (2022 July) and Cycle 2 (2023 September), to measure WR 140’s dust kinematics and confirm its morphology. To measure the proper motions and projected velocities of the dust shells, we performed a novel point-spread function (PSF) subtraction to reduce the effects of the bright diffraction spikes and carefully aligned the Cycle 2 to the Cycle 1 images. At 7.7 μm, through the bright feature common to 16 dust shells (C1), we find an average dust shell proper motion of 390 ± 29 mas yr−1, which equates to a projected velocity of 2714 ± 188 km s−1 at a distance of 1.64 kpc. Our measured speeds are constant across all visible shells and consistent with previously reported dust expansion velocities. Our observations not only prove that these dusty shells are astrophysical (i.e., not associated with any PSF artifact) and originate from WR 140, but also confirm the “clumpy” morphology of the dust shells, in which identifiable substructures within certain shells persist for at least 14 months from one cycle to the next. These results support the hypothesis that clumping in the wind collision region is required for dust production in WR binaries