44 research outputs found
An Analysis of RF Transfer Learning Behavior Using Synthetic Data
Transfer learning (TL) techniques, which leverage prior knowledge gained from
data with different distributions to achieve higher performance and reduced
training time, are often used in computer vision (CV) and natural language
processing (NLP), but have yet to be fully utilized in the field of radio
frequency machine learning (RFML). This work systematically evaluates how radio
frequency (RF) TL behavior by examining how the training domain and task,
characterized by the transmitter/receiver hardware and channel environment,
impact RF TL performance for an example automatic modulation classification
(AMC) use-case. Through exhaustive experimentation using carefully curated
synthetic datasets with varying signal types, signal-to-noise ratios (SNRs),
and frequency offsets (FOs), generalized conclusions are drawn regarding how
best to use RF TL techniques for domain adaptation and sequential learning.
Consistent with trends identified in other modalities, results show that RF TL
performance is highly dependent on the similarity between the source and target
domains/tasks. Results also discuss the impacts of channel environment,
hardware variations, and domain/task difficulty on RF TL performance, and
compare RF TL performance using head re-training and model fine-tuning methods.Comment: arXiv admin note: substantial text overlap with arXiv:2206.0832
ESG Framework for Investment Managers of WUIMC
ESG Framework for Investment Managers for Sustainability Exchange, Washington University in St. Louis, Fall 202
Addressing human resources for health needs to support HIV epidemic control: prioritizing site-level interventions in Democratic Republic of the Congo, 2018-2020
Introduction: The United States President's Emergency Plan for AIDS Relief (PEPFAR) in Democratic Republic of the Congo (DRC) continues to fund programs aimed at achieving epidemic control in three provinces where 30 percent of people living with HIV/AIDS in the country reside. Challenges around human resources for health impede the delivery of quality HIV/AIDS services in DRC. Methods: In partnership with the United States Health Resources and Services Administration (HRSA), PEPFAR, and DRC Ministry of Health (MoH), Columbia University's International Center for AIDS Prevention (ICAP at Columbia University) worked with 16 PEPFAR-identified high-priority health facilities and developed specific interventions to address challenges in achieving PEPFAR 95-95-95 targets. Once interventions were selected and prioritized using a collaborative, criteria-driven approach, implementation of these human resources for health improvements began alongside care and treatment efforts already underway. This study began in October 2018, and high-priority interventions were launched in July 2019. Monthly reporting of key PEPFAR metrics continues for evaluation purposes. Results: All 16 high-priority health facilities participated fully. Of several hypothesized interventions, 12 were selected as highest priority, and budgets and task plans were developed for each. The interventions were launched for implementation and evaluation within six months of Ministry of Health approval. Conclusion: This assessment delineated necessary interventions to address site-specific human resources for health challenges/deficiencies. Downstream reporting of key PEPFAR 95-95-95 metrics, including Monitoring, Evaluation, and Reporting indicators, will allow intervention teams to conduct program evaluations and their impacts on targets
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Increasing nursing student interest in rural healthcare: lessons from a rural rotation program in Democratic Republic of the Congo
Background
Many challenges exist in providing equitable access to rural healthcare in the Democratic Republic of the Congo (DRC). WHO recommends student exposure to rural clinical rotations to promote interest in rural healthcare. Challenges to rural engagement include lack of adequate infrastructure and staff to lead rural education. This case report highlights key steps in developing a rural rotation program for DRC nursing students.
Case presentation
To implement a rural rotation (RR) program, ICAP at Columbia University (ICAP) consulted with students, the Ministries of Health (MoH) and Education (MoE), and nursing schools to pilot and expand a rural rotation program. Nursing schools agreed to place students in rural clinics and communities. Key stakeholders collaborated to assess and select rural sites based on availability of nursing mentors, educational resources, security, accessibility, and patient volume. To support this, 85 preceptors from 55 target schools and 30 rural health facilities were trained of which 30 were selected to be “master trainers”. These master trainers led the remaining 55 preceptors implementing the rural rotation program. We worked with rural facilities to engage community leaders and secure accommodation for students.
A total of 583 students from five Lubumbashi schools and two rural schools outside Kinshasa participated across 16 rural sites (298 students in 2018–2019 school year and 285 in 2019–2020). Feedback from 274 students and 25 preceptors and nursing school leaders was positive with many students actively seeking rural assignments upon graduation. For example, 97% agreed or strongly agreed that their RR programs had strengthened their educational experience. Key challenges, however, were long-term financial support (35%) for rural rotations, adequate student housing (30%) and advocacy for expanding the rural workforce.
Conclusions
With nearly 600 participants, this project showed that a RR program is feasible and acceptable in resource-limited settings yet availability of ample student accommodation and increasing availability of rural jobs remain health system challenges. Using a multipronged approach to rural health investment as outlined by WHO over two decades ago remains essential. Attracting future nurses to rural health is necessary but not sufficient to achieve equitable health workforce distribution
Another Shipment of Six Short-Period Giant Planets from TESS
We present the discovery and characterization of six short-period, transiting
giant planets from NASA's Transiting Exoplanet Survey Satellite (TESS) --
TOI-1811 (TIC 376524552), TOI-2025 (TIC 394050135), TOI-2145 (TIC 88992642),
TOI-2152 (TIC 395393265), TOI-2154 (TIC 428787891), & TOI-2497 (TIC 97568467).
All six planets orbit bright host stars (8.9 <G< 11.8, 7.7 <K< 10.1). Using a
combination of time-series photometric and spectroscopic follow-up observations
from the TESS Follow-up Observing Program (TFOP) Working Group, we have
determined that the planets are Jovian-sized (R = 1.00-1.45 R),
have masses ranging from 0.92 to 5.35 M, and orbit F, G, and K stars
(4753 T 7360 K). We detect a significant orbital eccentricity
for the three longest-period systems in our sample: TOI-2025 b (P = 8.872 days,
= ), TOI-2145 b (P = 10.261 days, =
), and TOI-2497 b (P = 10.656 days, =
). TOI-2145 b and TOI-2497 b both orbit subgiant host
stars (3.8 g 4.0), but these planets show no sign of inflation
despite very high levels of irradiation. The lack of inflation may be explained
by the high mass of the planets; M (TOI-2145
b) and M (TOI-2497 b). These six new discoveries
contribute to the larger community effort to use {\it TESS} to create a
magnitude-complete, self-consistent sample of giant planets with
well-determined parameters for future detailed studies.Comment: 20 Pages, 6 Figures, 8 Tables, Accepted by MNRA
Identification of the top TESS objects of interest for atmospheric characterization of transiting exoplanets with JWST
Funding: Funding for the TESS mission is provided by NASA's Science Mission Directorate. This work makes use of observations from the LCOGT network. Part of the LCOGT telescope time was granted by NOIRLab through the Mid-Scale Innovations Program (MSIP). MSIP is funded by NSF. This paper is based on observations made with the MuSCAT3 instrument, developed by the Astrobiology Center and under financial support by JSPS KAKENHI (grant No. JP18H05439) and JST PRESTO (grant No. JPMJPR1775), at Faulkes Telescope North on Maui, HI, operated by the Las Cumbres Observatory. This paper makes use of data from the MEarth Project, which is a collaboration between Harvard University and the Smithsonian Astrophysical Observatory. The MEarth Project acknowledges funding from the David and Lucile Packard Fellowship for Science and Engineering, the National Science Foundation under grant Nos. AST-0807690, AST-1109468, AST-1616624 and AST-1004488 (Alan T. Waterman Award), the National Aeronautics and Space Administration under grant No. 80NSSC18K0476 issued through the XRP Program, and the John Templeton Foundation. C.M. would like to gratefully acknowledge the entire Dragonfly Telephoto Array team, and Bob Abraham in particular, for allowing their telescope bright time to be put to use observing exoplanets. B.J.H. acknowledges support from the Future Investigators in NASA Earth and Space Science and Technology (FINESST) program (grant No. 80NSSC20K1551) and support by NASA under grant No. 80GSFC21M0002. K.A.C. and C.N.W. acknowledge support from the TESS mission via subaward s3449 from MIT. D.R.C. and C.A.C. acknowledge support from NASA through the XRP grant No. 18-2XRP18_2-0007. C.A.C. acknowledges that this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). S.Z. and A.B. acknowledge support from the Israel Ministry of Science and Technology (grant No. 3-18143). The research leading to these results has received funding from the ARC grant for Concerted Research Actions, financed by the Wallonia-Brussels Federation. TRAPPIST is funded by the Belgian Fund for Scientific Research (Fond National de la Recherche Scientifique, FNRS) under the grant No. PDR T.0120.21. The postdoctoral fellowship of K.B. is funded by F.R.S.-FNRS grant No. T.0109.20 and by the Francqui Foundation. H.P.O.'s contribution has been carried out within the framework of the NCCR PlanetS supported by the Swiss National Science Foundation under grant Nos. 51NF40_182901 and 51NF40_205606. F.J.P. acknowledges financial support from the grant No. CEX2021-001131-S funded by MCIN/AEI/ 10.13039/501100011033. A.J. acknowledges support from ANID—Millennium Science Initiative—ICN12_009 and from FONDECYT project 1210718. Z.L.D. acknowledges the MIT Presidential Fellowship and that this material is based upon work supported by the National Science Foundation Graduate Research Fellowship under grant No. 1745302. P.R. acknowledges support from the National Science Foundation grant No. 1952545. This work is partly supported by JSPS KAKENHI grant Nos. JP17H04574, JP18H05439, JP21K20376; JST CREST grant No. JPMJCR1761; and Astrobiology Center SATELLITE Research project AB022006. This publication benefits from the support of the French Community of Belgium in the context of the FRIA Doctoral Grant awarded to M.T. D.D. acknowledges support from TESS Guest Investigator Program grant Nos. 80NSSC22K1353, 80NSSC22K0185, and 80NSSC23K0769. A.B. acknowledges the support of M.V. Lomonosov Moscow State University Program of Development. T.D. was supported in part by the McDonnell Center for the Space Sciences. V.K. acknowledges support from the youth scientific laboratory project, topic FEUZ-2020-0038.JWST has ushered in an era of unprecedented ability to characterize exoplanetary atmospheres. While there are over 5000 confirmed planets, more than 4000 Transiting Exoplanet Survey Satellite (TESS) planet candidates are still unconfirmed and many of the best planets for atmospheric characterization may remain to be identified. We present a sample of TESS planets and planet candidates that we identify as “best-in-class” for transmission and emission spectroscopy with JWST. These targets are sorted into bins across equilibrium temperature Teq and planetary radius Rp and are ranked by a transmission and an emission spectroscopy metric (TSM and ESM, respectively) within each bin. We perform cuts for expected signal size and stellar brightness to remove suboptimal targets for JWST. Of the 194 targets in the resulting sample, 103 are unconfirmed TESS planet candidates, also known as TESS Objects of Interest (TOIs). We perform vetting and statistical validation analyses on these 103 targets to determine which are likely planets and which are likely false positives, incorporating ground-based follow-up from the TESS Follow-up Observation Program to aid the vetting and validation process. We statistically validate 18 TOIs, marginally validate 31 TOIs to varying levels of confidence, deem 29 TOIs likely false positives, and leave the dispositions for four TOIs as inconclusive. Twenty-one of the 103 TOIs were confirmed independently over the course of our analysis. We intend for this work to serve as a community resource and motivate formal confirmation and mass measurements of each validated planet. We encourage more detailed analysis of individual targets by the community.Peer reviewe
31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two
Background
The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd.
Methods
We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background.
Results
First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001).
Conclusions
In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
Post-Traumatic Stress Disorder Symptoms and Alcohol Use in Firefighters: A Systematic Review
The purpose of this systematic literature review was to examine if there were any associations between post-traumatic stress disorder symptoms and alcohol use in firefighters. Sufficient evidence was found of an association, indicating that firefighters experiencing higher rates of PTSD symptoms also exhibit higher rates of alcohol use. A causal relationship was not found, and further research would need to be done in order to determine a cause