California Institute Research Articles

Use of Desktop Computers at the California Institute of Technology Libraries

Student access to desktop computers is still important in today’s age of portable electronic and mobile devices. This paper will examine a sample of student usage of desktop computers in a small university library. Survey results indicated that students do find having access to desktop computers is still relevant for their research and personal needs. This paper will show that library administration should continue to invest in desktop computers for student use, despite the common belief that notebooks, laptops, and mobile devices have overshadowed the need.

KBSS-InCLOSE. I. Design and First Results from the Inner Circumgalactic Medium of QSO Line-of-sight Emitting Galaxies at z ∼ 2–3 * * Some of the data presented herein were obtained at Keck Observatory, which is a private 501(c)3 non-profit organization operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and

We present the design and first results of the inner circumgalactic medium (CGM) of QSO line-of-sight emitting galaxies at z ∼ 2–3, Keck Baryonic Structure Survey (KBSS)-InCLOSE. The survey will connect galaxy properties (e.g., stellar mass M *, interstellar medium, hereafter ISM, metallicity) with the physical conditions of the inner CGM (e.g., kinematics, metallicity) to directly observe the galaxy-scale baryon cycle. We obtain deep Keck/KCWI optical IFU pointings of KBSS QSOs to discover new star-forming galaxies at small projected distances b ≲ 12″ (98 kpc, z¯=2.3 ), then obtain follow-up Keck/MOSFIRE near-IR spectra to confirm their redshifts. We leverage KBSS images and Keck/High Resolution Echelle Spectrometer QSO spectra to model stellar populations and inner CGM absorption. In this paper, we analyze two QSO fields and discover more than 15 new galaxies with KCWI, then use MOSFIRE for two galaxies Q2343-G1 (z = 2.43; G1) and Q2233-N1 (z = 3.15; N1), which are both associated with damped Lyα absorbers. We find that G1 has typical M *, UV/optical emission properties. N1 has lower M * with very strong nebular emission. We jointly analyze neutral phase CGM and ionized ISM in N/O (for the first time at this z), dust extinction, and high-ionization CGM finding that G1's CGM is metal poor and less evolved than its ISM, while N1's CGM and ISM abundances are comparable; their CGM shows ∼1 dex less dust extinction than the ISM; and G1's CGM has direct evidence of hot, metal-rich galactic outflow ejecta. These findings support that metals and dust are driven into the CGM from outflows, but may also be, e.g., stripped ISM gas or satellite enrichment. The full KBSS-InCLOSE sample will explore these scenarios.

Disrupting the Reproductive Lives of Japanese American Families During Wartime: The Overlapping Histories of Removal, Incarceration, and Eugenic Sterilization, 1942–1946

The World War II mass incarceration of 120,000 Japanese Americans disrupted families, enacted intergenerational trauma, and characterized Japanese Americans as inherent racial threats. This federal exercise in biopolitical management intersected with state-sponsored eugenic sterilization in California institutions. Linking War Relocation Authority and California Department of Institutions records, we document 32 Japanese American sterilization survivors during the wartime incarceration period (1942–1946). We show how federal and state authority converged to deprive Japanese Americans of civil rights and reproductive liberty. We add original research and analysis to the intertwined histories of Japanese American incarceration, eugenics, and family in the United States.

Design and Implementation of a Ka-band Folding Rib Mesh Antenna for CubeSats

In the past decade, CubeSats have undergone a revolution, moving from university research projects to enabling industry opportunities and government missions. In 2014, the Jet Propulsion Laboratory, California Institute of Technology (JPL/Caltech) initiated a research and technology development effort to advance CubeSat communication capabilities. One of the critical thrusts was the Ka-band parabolic deployable antenna (KaPDA). This antenna started with the ambitious goal of fitting a 42 dB, 0.5 m, 35 GHz antenna in a 1.5U canister. At that time, there had been minimal development in high-gain CubeSat antennas, critical for high-data-rate communications and remote sensing science. A Ka-band high-gain antenna would provide a 10,000 times increase in data communication rates over an X-band patch antenna and a 100 times increase over state-of-the-art S-band parabolic antennas. This paper discusses designing, building, integrating, and operating the flight antenna from a mechanical perspective, its final performance, and lessons learned. KaPDA enabled the RainCube mission, the first Earth Science CubeSat to have an active instrument. RainCube was launched in May 2018, making KaPDA the second deployable parabolic antenna to fly on a CubeSat and the first to operate in Ka-band, enabling follow-on opportunities for high-rate antenna communications and remote sensing science.

Two-Step Quadratic Programming for Physically Meaningful Smoothing of Longitudinal Vehicle Trajectories

Longitudinal vehicle trajectories suffer from errors and noise because of detection and extraction techniques, challenging their applications. Existing smoothing methods either lack physical meaning or cannot ensure solution existence and uniqueness. To address this, we propose a two-step quadratic programming method that aligns smoothed speeds and higher-order derivatives with physical laws, drivers’ behaviors, and vehicle characteristics. Unlike the well-known smoothing splines method, which minimizes a weighted sum of discrepancy and roughness in a single quadratic programming problem, our method incorporates prior knowledge of position errors into two sequential quadratic programming problems. Step 1 solves half-smoothed positions by minimizing the discrepancy between them and raw positions, subject to physically meaningful bounds on speeds and higher-order derivatives of half-smoothed positions. Step 2 solves smoothed positions by minimizing the roughness while maintaining physically meaningful bounds and allowing the deviations from raw data of smoothed positions by at most those of the half-smoothed positions and prior position errors. The second step’s coefficient matrix is not positive definite, necessitating the matching of the first few smoothed positions with corresponding half-smoothed ones, with equality constraints equaling the highest order of derivatives. We establish the solution existence and uniqueness for both problems, ensuring their well-defined nature. Numerical experiments using Next Generation Simulation (NGSIM) data demonstrate that a third-order derivative constraint yields an efficient method and produces smoothed trajectories comparable with manually re-extracted ones, consistent with the minimum jerk principle for human movements. Comparisons with an existing approach and application to the Highway Drone data set further validate our method’s efficacy. Notably, our method is a postprocessing smoothing technique based on trajectory data and is not intended for systematic errors. Future work will extend this method to lateral vehicle trajectories and trajectory prediction and planning for both human-driven and automated vehicles. This approach also holds potential for broader smoothing problems with known average error in raw data. History: This paper has been accepted for the Transportation Science Special Issue on ISTTT25 Conference. Funding: The authors extend their gratitude to the Pacific Southwest Region University Transportation Center and the University of California Institute of Transportation Studies (UC ITS) Statewide Transportation Research Program (STRP) for their valuable financial support.

Environmental Effects on the Stellar Mass Function in a z ∼ 3.3 Overdensity of Galaxies in the COSMOS Field* *Some of the data presented herein were obtained at Keck Observatory, which is a private 501(c)3 nonprofit organization operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The

We present an analysis of the number density of galaxies as a function of stellar mass (i.e., the stellar mass function (SMF)) in the COSMOS field at z ∼ 3.3, making a comparison between the SMF in overdense environments and the SMF in the coeval field. In particular, this region contains the Elentári proto-supercluster, a system of six extended overdensities spanning ∼70 cMpc on a side. A clear difference is seen in the high-mass slope of these SMFs, with overdense regions showing an increase in the ratio of high-mass galaxies to low-mass galaxies relative to the field, indicating a more rapid buildup of stellar mass in overdense environments. This result qualitatively agrees with analyses of clusters at z ∼ 1, though the differences between protocluster and field SMFs at z ∼ 3.3 are smaller. While this is consistent with overdensities enhancing the evolution of their member galaxies, potentially through increased merger rates, whether this enhancement begins in protocluster environments or even earlier in group environments is still unclear. Though the measured fractions of quiescent galaxies between the field and overdense environments do not vary significantly, implying that this stellar mass enhancement is ongoing and any starbursts triggered by merger activity have not yet quenched, we note that spectroscopic observations are biased toward star-forming populations, particularly for low-mass galaxies. If mergers are indeed responsible, high-resolution imaging of Elentári and similar structures at these early epochs should then reveal increased merger rates relative to the field. Larger samples of well-characterized overdensities are necessary to draw broader conclusions in these areas.

A Decade of Earth-Centered Scholarship and Activism

Abstract Origin stories reveal the myriad causes that converge to birth a new initiative. On the occasion of its tenth anniversary, this essay looks back to document the context and intellectual lineage out of which the Ecology, Spirituality, and Religion graduate program at the California Institute of Integral Studies (CIIS) emerged in 2013, and suggests some possibilities for the future of transdisciplinary education and the fields of religion and ecology (e.g. Tucker and Grim 2001), religion and nature (e.g. B. Taylor 2010), and spiritual ecology (e.g. Sponsel 2012) more broadly.

Revolutionizing consumer insights: the impact of fMRI in neuromarketing research

This study performs a comprehensive bibliometric (performance analysis) and thematic content analysis of global research in "neuromarketing or consumer neuroscience" and "functional magnetic resonance imaging or fMRI." Utilizing the PRISMA framework and R package software, we analyzed thirty-six Scopus-indexed articles. The USA and California Institute of Technology emerged as leading contributors, with Rangel, A., and Reimann, M., as notable authors. Prominent themes include 'advertising,' 'product,' 'price,' and 'brand', with the “Journal of Consumer Psychology” and “Journal of Neuroscience” being key publications. The most cited article is "Marketing actions can modulate neural representations of experienced pleasantness," with 620 citations. In addition, fMRI has been used to study consumer behavior (impulsiveness, reward, emotion, decision-making, and memory) toward marketing stimuli such as price (WTP), advertising (celebrity endorsement, MSV), product (packaging design), and brand (Halal logo, label, and personality). This study provides an invaluable literature review matrix and detailed insights into the current trends in global neuromarketing research utilizing fMRI. This study highlights the significant impact of fMRI in both academic and commercial realms, offering new insights for targeted marketing and consumer behavior research. It provides valuable guidance for developing more effective advertising strategies, understanding consumer decision-making processes, enhancing business performance, and collaborating academically.

Racial Micro-Affirmations: Latinx Close Friendships and Ethnic Identity Development

Through analysis of semi-structured interviews of 30 Latinx college students, we examined how Latinx students experience belonging, acceptance, and affirmations at a Hispanic-Serving Research Institution (HSRI) in California. Drawing from the theoretical perspectives of racial micro-affirmations, we uncovered two major themes: the importance of close friendships and the impact that ethnic studies courses have on ethnoracial identity development. This study contributes to the ongoing discussion of the on-campus experiences of underrepresented students as well as how to best serve and affirm them at HSRIs.

Idiopathic Subglottic Stenosis in Non-Caucasian Women.

To characterize presentation, disease course, and treatment of idiopathic subglottic stenosis (iSGS) in non-Caucasian women and compare this cohort to the predominantly female, Caucasian patient cohorts identified in the literature. Retrospective review. Results are compared to systematic review of demographics. Multiple California institutions from 2008 to 2021. Patients with intubation within 2 years of disease or who met exclusion criteria listed in prior publications were excluded. A systematic review of iSGS patient demographics was also completed for comparison. Of 421 patients with iSGS, 58 self-identified as non-Caucasian women, with 50 ultimately included. Mean age of onset was 45.1 years old (95% confidence interval [CI], 41.5-48.8), and mean age at diagnosis was 47.2 years (95% CI, 43.6-50.7). Mean Charlson comorbidity index was 1.06 (n = 49, 95% CI, 0.69-1.44). At diagnosis, Cotton-Meyer severity scores (documented in n = 45) were Cotton-Myer (CM) I (28.9%), CM II (40%), and CM III (31.1%). Mean age at first endoscopic surgery was 47.7 (95% CI, 44.2-51.3) years. 64% experienced disease recurrence with a median of 11 months between their first and second surgery. Our systematic review identified 60 studies that reported demographic features in patients with iSGS. 95% of pooled patients were Caucasian, while other demographic features were similar to the current cohort. The non-Caucasian population, almost 14% of this Californian cohort, does not differ from the majority Caucasian population detailed in contemporary literature. This cohort supports the presence of some racial and ethnic heterogeneity in this disease population.

The Web Epoch of Reionization Lyα Survey (WERLS). I. MOSFIRE Spectroscopy of z ∼ 7–8 Lyα Emitters* *The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the

We present the first results from the Web Epoch of Reionization Lyα Survey (WERLS), a spectroscopic survey of Lyα emission using Keck I/MOSFIRE and LRIS. WERLS targets bright (J < 26) galaxy candidates with photometric redshifts of 5.5 ≲ z ≲ 8 selected from pre-JWST imaging embedded in the Epoch of Reionization (EoR) within three JWST deep fields: CEERS, PRIMER, and COSMOS-Web. Here, we report 11 z ∼ 7–8 Lyα emitters (LAEs; three secure and eight tentative candidates) detected in the first five nights of WERLS MOSFIRE data. We estimate our observed LAE yield is ∼13%, which is broadly consistent with expectations assuming some loss from redshift uncertainty, contamination from sky OH lines, and that the Universe is approximately half-ionized at this epoch, whereby observable Lyα emission is unlikely for galaxies embedded in a neutral intergalactic medium. Our targets are selected to be UV-bright, and span a range of absolute UV magnitudes with −23.1 < M UV < −19.8. With two LAEs detected at z = 7.68, we also consider the possibility of an ionized bubble at this redshift. Future synergistic Keck+JWST efforts will provide a powerful tool for pinpointing beacons of reionization and mapping the large-scale distribution of mass relative to the ionization state of the Universe.

A Larger Sample Confirms Small Planets around Hot Stars Are Misaligned ∗ ∗ The data presented herein were obtained at the W. M. Keck Observatory, operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M.

The distribution of stellar obliquities provides critical insight into the formation and evolution pathways of exoplanets. In the past decade, it was found that hot stars hosting hot Jupiters are more likely to have high obliquities than cool stars, but it is not clear whether this trend exists only for hot Jupiters or holds for other types of planets. In this work, we extend the study of the obliquities of hot (6250–7000 K) stars with transiting super-Earth-sized and sub-Neptune-sized planets. We constrain the obliquity distribution based on measurements of the stars’ projected rotation velocities. Our sample consists of 170 TESS and Kepler planet-hosting stars and 180 control stars chosen to have indistinguishable spectroscopic characteristics. In our analysis, we find evidence suggesting that the planet hosts have a systematically higher 〈sini〉 compared to the control sample. This result implies that the planet hosts tend to have lower obliquities. However, the observed difference in 〈sini〉 is not significant enough to confirm spin–orbit alignment as it is 3.8σ away from perfect alignment. We also find evidence that within the planet-hosting stars there is a trend of higher obliquity (lower 〈sini〉 ) for the hotter stars (T eff > 6250 K) than for the cooler stars in the sample. This suggests that hot stars hosting smaller planets exhibit a broader obliquity distribution ( 〈sini〉=0.79±0.053 ) than cooler planet-hosting stars, indicating that high obliquities are not exclusive to hot Jupiters and instead are more broadly tied to hot stars.

The TESS-Keck Survey. VII. A Superdense Sub-Neptune Orbiting TOI-1824* *Some of the data presented herein were obtained at Keck Observatory, which is a private 501(c)3 nonprofit organization operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of

We confirm a massive sub-Neptune-sized planet on a P = 22.8 days orbit around the star TOI-1824 (T eff = 5200 K, V = 9.7 mag). TESS first identified TOI-1824 b (formerly TOI-1824.01) as an object of interest in 2020 April after two transits in Sector 22 were matched with a single transit in Sector 21. TOI-1824 was subsequently targeted for ground-based Doppler monitoring with Keck-HIRES and APF-Levy. Using a joint model of the TESS photometry, radial velocities, and Ca ii H and K emission measurements as an activity indicator, we find that TOI-1824 b is an unusually dense sub-Neptune. The planet has a radius R p = 2.63 ± 0.15 R ⊕ and mass M p = 18.5 ± 3.2 M ⊕, implying a bulk density of 5.6 ± 1.4 g cm−3. TOI-1824 b's mass and radius situate it near a small group of “superdense sub-Neptunes” (R p ≲ 3 R ⊕ and M p ≳ 20 M ⊕). While the formation mechanism of superdense sub-Neptunes is a mystery, one possible explanation is the constructive collision of primordial icy cores; such giant impacts would drive atmospheric escape and could help explain these planets' apparent lack of massive envelopes. We discuss TOI-1824 b in the context of these overdense planets, whose unique location in the exoplanet mass–radius plane make them a potentially valuable tracer of planet formation.

The people behind the papers - Jingjing Sun and Angelike Stathopoulos.

Collective migration of caudal visceral mesoderm (CVM) cells in Drosophila embryos helps form the longitudinal muscles of the larval gut. In their study, Angelike Stathopoulos and colleagues reveal that cell division coordinates two gene expression programmes in migrating CVM cells. To know more about their work, we spoke to the first author, Jingjing Sun, and the corresponding author, Angelike Stathopoulos, Professor in the Division of Biology at the California Institute of Technology, USA.

Robert Millikan, Japanese internment, and eugenics

Robert A. Millikan (1868–1953) was the second American to win the Nobel Prize in physics. At the peak of his influence, no scientist save Einstein was more admired by the American public. Millikan, the head of the California Institute of Technology (Caltech) during its first 24 years, oversaw its rapid growth into one of the leading scientific institutions of the world. However, in response to demands for social justice following the murder of George Floyd, Caltech launched an investigation into Millikan. Caltech reached a decision to strip Millikan of honors (such as the library named after him), following accusations from various sources that he was a sexist, racist, xenophobic, antisemitic, pro-eugenic Nazi sympathizer. In short, Caltech threw the book at him. This article analyzes two accusations against Millikan. The first of these accusations was published in Nature: that he collaborated to deprive Japanese Americans of their rights during their forced relocation to internment camps during the Second World War. An examination of original historical sources will show that this accusation is false. On the contrary, Millikan actively campaigned during the war to promote the rights of Japanese Americans. This article traces the stages of misrepresentation that led to current false beliefs about Millikan. In view of Millikan’s extraordinary position in American science, this misrepresentation is a cautionary tale. The article also treats Caltech’s central accusation against Millikan: he lent his name to “a morally reprehensible eugenics movement” that had been scientifically discredited in his time. The article considers the statements purporting to show that eugenics movement had been denounced by the scientific community by 1938. In a reversal of Caltech’s claims, all three of Caltech’s scientific witnesses against eugenics—including two Nobel laureates—were actually pro-eugenic to varying degrees. This article concludes that Millikan’s beliefs fell within acceptable scientific norms of his day.

Abstract PO1-11-11: A Novel Body Composition Risk Score (B-Score) and Overall Survival among Patients with Early-Stage Breast Cancer

Abstract Background: Measurements (amount, distribution, and radiodensity) of muscle and adipose tissue were reported to be individually associated with overall survival in breast cancer survivors, but they were not typically combined to develop an overall risk score. Such a score can identify patients at high risk of death and prioritize patients in need of lifestyle interventions. Objectives: We developed a novel body composition risk score (B-Score) by combining multiple tissue measurements. Methods: We included 3105 patients with stage II or III breast cancer (diagnosed from 2000 to 2013) at Kaiser Permanente Northern California and Dana Farber Cancer Institute. From CT scans at diagnosis, we used the third lumber vertebrae as the landmark to assess areas (cm2) and radiodensity (HU) of muscle and adipose tissue. We divided the area by height2 (m2) to derive the index and measured the average HU of the tissue area as the radiodensity, which acts as a marker of tissue 'quality' to be indicative of lipid content, inflammation, and angiogenesis. Out of all tissue measurements, we considered skeletal muscle index (SMI), subcutaneous adipose tissue index (SATI) and SAT radiodensity as they were independent predictors for overall survival. Each measurement was dichotomized using optimal stratification, with low SMI (&amp;lt; 40.1cm2/m2), high SATI (≥75.7cm2/m2), and high SAT radiodensity (≥ -97.2HU) considered risk factors. We calculated B-Score as the sum of these factors and estimated its association with overall survival using Cox proportional hazards regression with adjustment for clinicopathologic factors. Results: Mean (standard deviation) age at diagnosis was 53.9 (11.8) years, 2161 (70.1%) were Non-Hispanic White, 1880 (60.5%) were stage II, and 919 (29.6%) died over a median follow-up of 10.7 years. Most patients (60.6%) had only one body composition risk factor (B-Score = 1). Compared to those with no body composition risk factors (B-Score = 0), the risk of death increased with more body composition risk factors: the adjusted hazard ratios were 1.10 (95% CI: 0.85, 1.42), 1.47 (95% CI: 1.12, 1.92), and 2.11 (95% CI: 1.26, 3.53) for B-Scores of 1, 2, and 3, respectively (Ptrend &amp;lt; 0.001). Conclusions: More unfavorable body composition characteristics were associated with increased risks of overall mortality in a dose-response manner. Considering body composition measurements together as a composite score (B-Score) may prove a useful tool to identify patients at high risk of death following breast cancer diagnosis. Table. Adjusted Associations of the Body Composition Risk Score (B-Score) with Overall Mortality Among Patients with Early-Stage Breast Cancer Abbreviations: HR, hazard ratio. a Areas (cm2) and radiodensity (HU) of skeletal muscle and subcutaneous adipose tissue (SAT) were extracted from the single axial CT slice at the third lumbar vertebra. The body composition risk score was defined as the sum of three risk factors: low skeletal muscle index (SMI; &amp;lt;40.1cm2/m2), high SAT index (SATI; ≥75.7cm2/m2), and high SAT radiodensity (≥ -97.2HU). b Adjusted for age (years), race and ethnicity (Asian, Black, Hispanic, Non-Hispanic White, and Others), stage (II, III), ER (ER+, ER-), PR (PR+, PR-), HER2 (HER2+, HER2-, unknown), smoking (current, former, never), Charlson comorbidity index (0, 1-2, ≥3), and BMI (&amp;lt;18.5, 28.5-24.9, 25-29.9, and ≥30 kg/m2). For the trend test, B-Score was considered as a continuous variable with adjustment for the above covariates. Citation Format: En Cheng, Bette Caan, Wendy Chen, Carla Prado, Elizabeth Cespedes Feliciano. A Novel Body Composition Risk Score (B-Score) and Overall Survival among Patients with Early-Stage Breast Cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-11-11.

Regeneration of Neuromuscular Synapses by Inhibition of the Prostaglandin Degrading Enzyme 15-PGDH

Background: Skeletal muscles require voluntary activation to move, which is supplied via motor neurons. The terminal axons of motor neurons innervate muscle fibers at the neuromuscular junction (NMJ). NMJ degeneration increases with age and injury, decreasing muscle contractility and strength and severely reducing individuals’ quality of life. Treatments able to restore NMJ integrity and muscle innervation after injury and in aging are currently lacking. Aim: Our lab has recently shown that boosting prostaglandin E2 (PGE2) levels in aged mice by inhibiting its degrading enzyme 15-prostaglandin dehydrogenase (15-PGDH) stimulates muscle growth and restores muscle strength and endurance. The present study aimed at investigating whether 15-PGDH inhibition promotes muscle reinnervation and NMJ restoration, thus improving muscle function. Methods and results: We treated young (3-month) and old (27-month) mice with a small molecule compound with high specificity for 15-PGDH inhibition for 30 days. Old treated mice displayed increased muscle mass and strength (p&lt;0.05) compared to aged control mice. While aged control displayed, as expected, a high percentage of denervated NMJ (21.6%), denervation was partially rescued by 15-PGDH inhibition (12.1%, p&lt;0.05). Similarly, NMJ fragmentation was lower in treated versus control mice (18.1% vs 29.3%, p&lt;0.05). To translate our findings to a more acute scenario, we induced nerve-crush injury in young mice (3-month) and treated animals with 15-PGDH inhibition during injury recovery. Treated mice were able to exert a 37.2% higher tetanic force 14 days after injury compared to control mice. This was accompanied by increased muscle mass and specific force (+32.2%, p&lt;0.05) and an increased percentage of innervated NMJs (97.4% versus 84.5%) in treated versus control mice, suggesting that 15-PGDH inhibition was promoting NMJ restoration and muscle reinnervation after injury. Conclusion: In this study we identify 15-PGDH inhibition as a new potential therapeutic strategy to promote reinnervation of NMJs and strength recovery after acute or chronic denervation due to injury or aging. Funding: E.M. is supported by a “Wu Tsai Human Performance Alliance” fellowship. This study was supported by the Donald E. and Delia B. Baxter Foundation, the Li Ka Shing Foundation, Milky Way Research Foundation MWRF-216064, California Institute for Regenerative Medicine grant DISC2-10604, and U.S. National Institutes of Health (NIH) grants R01-AG020961, R01-AG069858, and R01-RHG009674 to H.M.B. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

The effect of VEGF-A isoforms on capillary endothelial cell differentiation in human fetal lung development

Rationale: Single-cell RNA-sequencing has revealed two distinct capillary cell populations in the lung - general capillary cells (gCap) and alveolar capillary cells (aCap). Studies in mouse have demonstrated that VEGF-A188 promotes the formation of aCaps in vitro. Our study investigates the role of VEGF-A in endothelial cell (EC) differentiation into functional pulmonary capillaries during human lung development. We hypothesize that VEGFA-189, the human equivalent of murine VEGFA-188, promotes the formation of aCaps in the developing human lung. Methods: We examined the expression of the different VEGF-A isoforms ( VEGF-A121, 145, 165 and 189) on human fetal lungs aged 10-20 weeks gestation. RT-qPCR was performed to correlate the expression of VEGF-A isoforms to the expression of aCap makers ( CA4, EDNRB, SOSTDC1, HPGD, TBX2 and IL1RL1). In parallel to these analyses, we examined the effects of VEGF-A isoforms by culturing human fetal lung explants (13-20 weeks gestation) for either 2 or 7 days in the presence or absence of either recombinant human protein VEGF-A165 (20 ng/mL) or VEGF-A189 (80 ng/mL) (n=8). To verify this hypothesis of VEGF-A189, we selected VEGF-A165 which has one exon less (exon 6) than VEGF-A189. Explants were collected and analyzed for gCap ( EDN1) and aCap ( TBX2, EDNRB, SOSTDC1, HPGD, and CA4) markers expression by RT-qPCR. Immunofluorescence (IF) staining was also performed on explants to analyze the effect of VEGF-A isoforms on the proliferation of endothelial cell. Results: In native human fetal lung, we demonstrated a simultaneous expression of VEGF-A-121, 145 and 189 isoforms with several aCap markers ( SOSTDC1, EDNRB, HPGD), that peaked at around 18 weeks of gestation. Based on this, we decided to culture human fetal lung explants within this same developmental stage in the presence or absence of either VEGF-A165 or -189. Following 2 days treatment with VEGF-A165, RT-qPCR demonstrated that human fetal lung explants exhibited a significant increase in the expression of EDN1 (p&lt;0.005), accompanied by a significant decrease in expression of CA4 (p&lt;0.005). Interestingly, whereas VEGF-A189 also demonstrated decreased expression of several aCap markers ( CA4, EDNRB, SOSTDC1, and HPGD (p&lt;0.01)) it also showed increased expression of TBX2 and EDN1 (p&lt;0.05). Furthermore, IF staining displayed decreased Ki67/CD31 double positive cells on explants treated with VEGF-A189 with a more elongated and flattened morphology, much like what is observed in aCaps. Prolonging the treatment to 7 days yielded comparable results to the 2 days treatment, with VEGF-A165 and VEGF-A189 downregulating several aCap markers. Conclusion: Our study revealed that the VEGF-A189 isoform does not have the same effect on human lung capillary differentiation as observed in mouse. We noted a contrasting impact of VEGF-A isoforms on the expression of gCap and aCap markers and highlighted the significance of specific VEGF isoforms in capillary EC differentiation. Additional investigations are required to elucidate the underlying mechanisms. California Institute for Regenerative Medicine-CIRM. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

A novel body composition risk score (B-Score) and overall survival among patients with nonmetastatic breast cancer

Measurements (amount, distribution, and radiodensity) of muscle and adipose tissue were reported to be individually associated with overall survival in patients with breast cancer. However, they were not typically combined to develop an overall risk score, which can identify patients at high risk of death and prioritize patients in need of dietary and lifestyle interventions. Thus, we aimed to develop a novel composite body composition risk score (B-Score). We included 3105 patients with stage II or III breast cancer at Kaiser Permanente Northern California and Dana Farber Cancer Institute. From CT scans at diagnosis, we assessed areas and radiodensity of muscle and adipose tissue at the third lumber vertebrae. We considered skeletal muscle index (SMI), subcutaneous adipose tissue index (SATI) and SAT radiodensity as they were independent prognostic factors for overall survival. Each measurement was dichotomized using optimal stratification, with low SMI (<40.1cm2/m2), high SATI (≥75.7cm2/m2), and high SAT radiodensity (≥-97.2HU) considered risk factors. We calculated B-Score as the sum of these factors and estimated its association with overall survival using Cox proportional hazards regression with adjustment for clinicopathologic factors. Mean (standard deviation) age was 53.9 (11.8) years, 70.3% were Non-Hispanic White, and 60.5% were stage II. Most patients (60.6%) had only one body composition risk factor (B-Score=1). Compared to those with no risk factors (B-Score=0), the risk of death increased with more body composition risk factors: the adjusted hazard ratios were 1.10 (95% CI: 0.85, 1.42), 1.47 (95% CI: 1.12, 1.92), and 2.11 (95% CI: 1.26, 3.53) for B-Scores of 1, 2, and 3, respectively (Ptrend < 0.001). More unfavorable body composition characteristics were associated with increased risks of overall mortality in a dose-response manner. Considering body composition measurements together as a composite score (B-Score) may improve risk stratification and inform dietary and lifestyle interventions following breast cancer diagnosis.

Disparities in pre-health advising across California's public universities.

The Supreme Court's decision in Students for Fair Admissions, Inc., v. Harvard College is likely to result in the matriculation of fewer students from historically excluded racial/ethnic groups at more selective colleges and universities and matriculation of more students at less selective colleges and universities. Because of this, it is important to understand how resources for pre-health advising, a modifiable factor that can help increase the diversity of the health workforce, vary across institutions with differing levels of selectivity. Colleges are known to vary in resources, structure, and investment in pre-health advising but data are lacking and there is no estimate of any pre-health advising resource gap. To quantify availability of advising resources and identify perceived challenges in pre-health advising in California's highly diverse public and select private undergraduate institutions. Structured 60-minute Zoom interviews from June 2022 -October 2022 at 18/23 CSU (California State Universities), 9/9 University of California (UC) institutions and 6 select private institutions with varying levels of selectivity. Two investigators independently analyzed interviews using a Grounded Theory Approach. The full study team reviewed transcripts and themes. Pre-health advisor capacity varied greatly across the three types of institutions. CSU: mean = 1 FTE advisor: 24,620 graduates (range: 1: 1,059-1: 150,520); UC mean = 1 FTE advisor: 4,526 graduates (range: 1: 1,912-1: 10,920); private institutions mean = 1 FTE advisor:1,794 graduates (range: 1: 722-1: 5,300). Participants reported common challenges: advising capacity, lack of advisor training, advisor turnover, and student difficulties in accessing clinical opportunities and required coursework. CSU and UC participants noted that these had greatest impact for first generation and racially/ethnically underrepresented students for whom lack of informal professional networks, lack of other mentors, and financial responsibilities complicate college navigation and professional school application. Students at CSU campuses had 5 times less access to pre-health advising per graduate than UC students, and 13 times less than students at private institutions. Much greater investment is needed in California's public institutions, particularly CSUs, to increase equity in access to advising for pre-health professional students. Research should examine pre-health advising resource capacity in other states, especially those that are now facing race-neutral admissions policies at undergraduate institutions and health professions schools.