1,083 research outputs found
SpeckleNN: A unified embedding for real-time speckle pattern classification in X-ray single-particle imaging with limited labeled examples
With X-ray free-electron lasers (XFELs), it is possible to determine the
three-dimensional structure of noncrystalline nanoscale particles using X-ray
single-particle imaging (SPI) techniques at room temperature. Classifying SPI
scattering patterns, or "speckles", to extract single hits that are needed for
real-time vetoing and three-dimensional reconstruction poses a challenge for
high data rate facilities like European XFEL and LCLS-II-HE. Here, we introduce
SpeckleNN, a unified embedding model for real-time speckle pattern
classification with limited labeled examples that can scale linearly with
dataset size. Trained with twin neural networks, SpeckleNN maps speckle
patterns to a unified embedding vector space, where similarity is measured by
Euclidean distance. We highlight its few-shot classification capability on new
never-seen samples and its robust performance despite only tens of labels per
classification category even in the presence of substantial missing detector
areas. Without the need for excessive manual labeling or even a full detector
image, our classification method offers a great solution for real-time
high-throughput SPI experiments
On a three-dimensional and two four-dimensional oncolytic viro-therapy models
We revisit here and carry out further works on tumor-virotherapy
compartmental models of [Tian, 2011, Wang et al., 2013, Phan and Tian, 2017,
Guo et al., 2019]. The results of these papers are only slightly pushed
further. However, what is new is the fact that we make public our electronic
notebooks, since we believe that easy electronic reproducibility is crucial in
an era in which the role of the software becomes very important.Comment: 41 pages, 15 figure
The P174L mutation in human Sco1 severely compromises Cox17-dependent metallation but does not impair copper binding.
International audienceSco1 is a metallochaperone that is required for copper delivery to the Cu(A) site in the CoxII subunit of cytochrome c oxidase. The only known missense mutation in human Sco1, a P174L substitution in the copper-binding domain, is associated with a fatal neonatal hepatopathy; however, the molecular basis for dysfunction of the protein is unknown. Immortalized fibroblasts from a SCO1 patient show a severe deficiency in cytochrome c oxidase activity that was partially rescued by overexpression of P174L Sco1. The mutant protein retained the ability to bind Cu(I) and Cu(II) normally when expressed in bacteria, but Cox17-mediated copper transfer was severely compromised both in vitro and in a yeast cytoplasmic assay. The corresponding P153L substitution in yeast Sco1 was impaired in suppressing the phenotype of cells harboring the weakly functional C57Y allele of Cox17; however, it was functional in sco1delta yeast when the wild-type COX17 gene was present. Pulse-chase labeling of mitochondrial translation products in SCO1 patient fibroblasts showed no change in the rate of CoxII translation, but there was a specific and rapid turnover of CoxII protein in the chase. These data indicate that the P174L mutation attenuates a transient interaction with Cox17 that is necessary for copper transfer. They further suggest that defective Cox17-mediated copper metallation of Sco1, as well as the subsequent failure of Cu(A) site maturation, is the basis for the inefficient assembly of the cytochrome c oxidase complex in SCO1 patients
Unlocking Community Capabilities Across Health Systems in Low- and Middle-Income Countries: Lessons Learned from Research and Reflective Practice
The right and responsibility of communities to participate
in health service delivery was enshrined in the 1978
Alma Ata declaration and continues to feature centrally
in health systems debates today. Communities are
a vital part of people-centred health systems and
their engagement is critical to realizing the diverse
health targets prioritised by the Sustainable Development
Goals and the commitments made to Universal
Health Coverage. Community members' intimate
knowledge of local needs and adaptive capacities are essential
in constructively harnessing global transformations
related to epidemiological and demographic transitions,
urbanization, migration, technological innovation and
climate change. Effective community partnerships and
governance processes that underpin community capability
also strengthen local resilience, enabling communities to
better manage shocks, sustain gains, and advocate for
their needs through linkages to authorities and services.
This is particularly important given how power relations
mark broader contexts of resource scarcity and concentration,
struggles related to social liberties and other types of
ongoing conflicts.IS
Severe lung fibrosis requires an invasive fibroblast phenotype regulated by hyaluronan and CD44
Hyaluronan synthase 2 and CD44 are required for severe lung fibrosis in response to bleomycin
Recommended from our members
Continuation vs Discontinuation of Renin-Angiotensin System Inhibitors Before Major Noncardiac Surgery
ImportanceBefore surgery, the best strategy for managing patients who are taking renin-angiotensin system inhibitors (RASIs) (angiotensin-converting enzyme inhibitors or angiotensin receptor blockers) is unknown. The lack of evidence leads to conflicting guidelines.ObjectiveTo evaluate whether a continuation strategy vs a discontinuation strategy of RASIs before major noncardiac surgery results in decreased complications at 28 days after surgery.Design, setting, and participantsRandomized clinical trial that included patients who were being treated with a RASI for at least 3 months and were scheduled to undergo a major noncardiac surgery between January 2018 and April 2023 at 40 hospitals in France.InterventionPatients were randomized to continue use of RASIs (n = 1107) until the day of surgery or to discontinue use of RASIs 48 hours prior to surgery (ie, they would take the last dose 3 days before surgery) (n = 1115).Main outcomes and measuresThe primary outcome was a composite of all-cause mortality and major postoperative complications within 28 days after surgery. The key secondary outcomes were episodes of hypotension during surgery, acute kidney injury, postoperative organ failure, and length of stay in the hospital and intensive care unit during the 28 days after surgery.ResultsOf the 2222 patients (mean age, 67 years [SD, 10 years]; 65% were male), 46% were being treated with angiotensin-converting enzyme inhibitors at baseline and 54% were being treated with angiotensin receptor blockers. The rate of all-cause mortality and major postoperative complications was 22% (245 of 1115 patients) in the RASI discontinuation group and 22% (247 of 1107 patients) in the RASI continuation group (risk ratio, 1.02 [95% CI, 0.87-1.19]; P = .85). Episodes of hypotension during surgery occurred in 41% of the patients in the RASI discontinuation group and in 54% of the patients in the RASI continuation group (risk ratio, 1.31 [95% CI, 1.19-1.44]). There were no other differences in the trial outcomes.Conclusions and relevanceAmong patients who underwent major noncardiac surgery, a continuation strategy of RASIs before surgery was not associated with a higher rate of postoperative complications than a discontinuation strategy.Trial registrationClinicalTrials.gov Identifier: NCT03374449
Middle Eastern Cities in a Time of Climate Crisis
The climate crisis is hitting around the world, including in the Middle East and its cities. Urban regions are exposed to increasingly frequent heat waves and floods that leave decision makers without immediate answers. In the context of this global crisis, this book addresses the need for a better understanding of the current model of urban expansion. Cities are major sources of greenhouse gas (GHG) emissions but they are also celebrated for their contribution to economic growth. The current moment is one of a large paradigm shift as climate change is now recognized as a legitimate public problem. This is especially true for city dwellers, who are increasingly exposed to climate change, the loss of biodiversity and heavy pollution while natural breathing spaces continue to shrink around them. The sixteen chapters of this book do not offer any off-the-rack or technical solutions, but they analyze the urban conundrum and the contribution of cities to the climate crisis. Some chapters focus on individual car ownership, land privatization, waste management and land use changes under the guise of development. Others explore local and contextual answers to urban governance issues. With the support of CEDEJ and the Friedrich-Ebert-Stiftung, researchers, experts and civil society actors explore the ongoing transformations of Middle Eastern urban environments and mobilities and question them in relation to the climate crisis. The contributions are based on empirical knowledge gathered in the Nile Delta, the Greater Cairo Region, Riyadh and Beirut. Without concessions to mainstream thinking, this book contributes to a better understanding of urban challenges, climate threats and policy responses in contexts marked by growing environmental inequalities
iPTF Archival Search for Fast Optical Transients
There has been speculation about a class of relativistic explosions with an initial Lorentz factor Γ_(init) smaller than that of classical gamma-ray bursts (GRBs). These "dirty fireballs" would lack prompt GRB emission but could be pursued via their optical afterglow, appearing as transients that fade overnight. Here we report a search for such transients (that fade by 5-σ in magnitude overnight) in four years of archival photometric data from the intermediate Palomar Transient Factory (iPTF). Our search criteria yielded 50 candidates. Of these, two were afterglows to GRBs that had been found in dedicated follow-up observations to triggers from the Fermi GRB Monitor. Another (iPTF14yb) was a GRB afterglow discovered serendipitously. Eight were spurious artifacts of reference image subtraction, and one was an asteroid. The remaining 38 candidates have red stellar counterparts in external catalogs. The photometric and spectroscopic properties of the counterparts identify these transients as strong flares from M dwarfs of spectral type M3–M7 at distances of d ≈ 0.15–2.1 kpc; three counterparts were already spectroscopically classified as late-type M stars. With iPTF14yb as the only confirmed relativistic outflow discovered independently of a high-energy trigger, we constrain the all-sky rate of transients that peak at m = 18 and fade by Δm = 2 mag in Δt = 3 hr to be 680 yr^(-1), with a 68% confidence interval of 119-2236, yr^(-1). This implies that the rate of visible dirty fireballs is at most comparable to that of the known population of long-duration GRBs
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