national laboratory
Recently Published Documents


TOTAL DOCUMENTS

5423
(FIVE YEARS 561)

H-INDEX

54
(FIVE YEARS 7)

2022 ◽  
Vol 33 (1) ◽  
pp. 50
Author(s):  
Eduardo Sánchez-Lara

<p><span>La Mioglobina fue la primer proteína visualizada en tres dimensiones (3D) a través de la cristalografía de rayos-X, sentando las bases para una nueva era de comprensión biológica. A partir de este hecho, se comenzaron a determinar estructuralmente una serie de macromoléculas de considerable interés biológico. Sin embargo, este impresionante avance en las ciencias de la vida, contrastaba radicalmente con la ausencia de un repositorio global para archivar y compartir los datos cristalográficos colectados de los experimentos de difracción. Con el propósito de llenar este vacío, en 1971 se estableció el Protein Data Bank (PDB) en el Brookhaven National Laboratory, como el único almacén central de estructuras 3D de macromoléculas biológicas. Establecido con apenas siete estructuras, el PDB ha evolucionado a un gigantesco repositorio de acceso abierto, almacenando datos estructurales de más de 170,000 biomoléculas, principalmente de proteínas y ácidos nucleicos. Además de ser un banco de datos biológicos, el PDB sirve como un portal educativo a través del PDB-101, ofreciendo un conjunto de recursos extraordinarios para admirar el mundo biológico. En esta revisión, festejamos los 50 años de oro del PDB con una mirada a su historia y un recorrido por algunas herramientas educativas que el archivo pone a disposición de estudiantes, investigadores, profesores y público no especializado. Ilustramos el valor de estos recursos con la estructura 3D de la maquinaria biológica recientemente depositada en el archivo, del ubicuo y nuevo coronavirus causante del síndrome respiratorio agudo severo (SARS-CoV-2) o COVID-19.</span></p>


2022 ◽  
Vol 12 (1) ◽  
pp. 503
Author(s):  
João Leite ◽  
Paulo B. Lourenço ◽  
Nuno Mendes

Several factors influence the behaviour of masonry infilled frames, which have been the subject of previous research with moderate success. The new generation of European design standards imposes the need to prevent the brittle collapse of infills and makes the structural engineer accountable for this requirement, yet it fails to provide sufficient information for masonry infill design. The present study aimed to compare experimental results with the provisions of the standard for the computation of the demand and capacity of infilled frames. Three reinforced concrete buildings with different infill solutions were constructed at a 1:1.5 scale. The infill walls were tested until collapse, or severe damage, using the shake table of the National Laboratory for Civil Engineering, Portugal, and their response was measured using accelerometers attached to the walls. The European normative standard provides results close to the experimental ones as far as demand and capacity are concerned. Based on the experiments, two design proposals for infill walls are presented here, one for the definition of the natural frequency of the infills, and another for a reduction factor to account for the presence of openings in the out-of-plane capacity of infills.


2021 ◽  
Vol 7 (1) ◽  
pp. 5
Author(s):  
Eugenia Naselli ◽  
Richard Rácz ◽  
Sandor Biri ◽  
Maria Mazzaglia ◽  
Luigi Celona ◽  
...  

At the Italian National Institute for Nuclear Physics-Southern National Laboratory (INFN-LNS), and in collaboration with the ATOMKI laboratories, an innovative multi-diagnostic system with advanced analytical methods has been designed and implemented. This is based on several detectors and techniques (Optical Emission Spectroscopy, RF systems, interfero-polarimetry, X-ray detectors), and here we focus on high-resolution, spatially resolved X-ray spectroscopy, performed by means of a X-ray pin-hole camera setup operating in the 0.5–20 keV energy domain. The diagnostic system was installed at a 14 GHz Electron Cyclotron Resonance (ECR) ion source (ATOMKI, Debrecen), enabling high-precision, X-ray, spectrally resolved imaging of ECR plasmas heated by hundreds of Watts. The achieved spatial and energy resolutions were 0.5 mm and 300 eV at 8 keV, respectively. Here, we present the innovative analysis algorithm that we properly developed to obtain Single Photon-Counted (SPhC) images providing the local plasma-emitted spectrum in a High-Dynamic-Range (HDR) mode, by distinguishing fluorescence lines of the materials of the plasma chamber (Ti, Ta) from plasma (Ar). This method allows for a quantitative characterization of warm electrons population in the plasma (and its 2D distribution), which are the most important for ionization, and to estimate local plasma density and spectral temperatures. The developed post-processing analysis is also able to remove the readout noise that is often observable at very low exposure times (msec). The setup is now being updated, including fast shutters and trigger systems to allow simultaneous space and time-resolved plasma spectroscopy during transients, stable and turbulent regimes.


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0260979
Author(s):  
Manickam Ponnaiah ◽  
Rizwan Suliankatchi Abdulkader ◽  
Tarun Bhatnagar ◽  
Jeromie Wesley Vivian Thangaraj ◽  
Muthusamy Santhosh Kumar ◽  
...  

Background The Indian Council of Medical Research set up a pan-national laboratory network to diagnose and monitor Coronavirus disease 2019 (COVID-19). Based on these data, we describe the epidemiology of the pandemic at national and sub-national levels and the performance of the laboratory network. Methods We included surveillance data for individuals tested and the number of tests from March 2020 to January 2021. We calculated the incidence of COVID-19 by age, gender and state and tests per 100,000 population, the proportion of symptomatic individuals among those tested, the proportion of repeat tests and test positivity. We computed median (Interquartile range—IQR) days needed for selected surveillance activities to describe timeliness. Results The analysis included 176 million individuals and 188 million tests. The overall incidence of COVID-19 was 0.8%, and 12,584 persons per 100,000 population were tested. 6.1% of individuals tested returned a positive result. Ten of the 37 Indian States and Union Territories accounted for about 75.6% of the total cases. Daily testing scaled up from 40,000 initially to nearly one million in March 2021. The median duration between symptom onset and sample collection was two (IQR = 0,3) days, median duration between both sample collection and testing and between testing and data entry were less than or equal to one day. Missing or invalid entries ranged from 0.01% for age to 0.7% for test outcome. Conclusion The laboratory network set-up by ICMR was scaled up massively over a short period, which enabled testing a large section of the population. Although all states and territories were affected, most cases were concentrated in a few large states. Timeliness between the various surveillance activities was acceptable, indicating good responsiveness of the surveillance system.


Physics World ◽  
2021 ◽  
Vol 34 (12) ◽  
pp. 11ii-11ii
Author(s):  
Michael Banks

Leading physics facilities including CERN, the European Space Agency, Fermilab and the Los Alamos National Laboratory plan to step up scientific collaboration on carbon-neutral energy and climate change.


Physics World ◽  
2021 ◽  
Vol 34 (10) ◽  
pp. 11ii-11ii
Author(s):  
Michael Banks

Scientists at the Lawrence Livermore National Laboratory in California say they have come closer to realizing “ignition”, at which fusion reactions generate at least as much energy as its lasers put in.


Physics World ◽  
2021 ◽  
Vol 34 (11) ◽  
pp. 15iii-15iii

The Borexino neutrino experiment at the Gran Sasso National Laboratory in central Italy has shut down after 14 years of operation.


Symmetry ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2278
Author(s):  
Hao Jian ◽  
Yufeng Gao ◽  
Fanchao Dai ◽  
Jiajian Liu ◽  
Xinxing Xu ◽  
...  

The study of the origin of asymmetries in mirror β decay is extremely important to understand the fundamental nuclear force and the nuclear structure. The experiment was performed at the National Laboratory of Heavy Ion Research Facility in Lanzhou (HIRFL) to measure the β-delayed γ rays of 26P by silicon array and Clover-type high-purity Germanium (HPGe) detectors. Combining with results from the β decay of 26P and its mirror nucleus 26Na, the mirror asymmetry parameter δ ( ≡ft+/ft−− 1) was determined to be 46(13)% for the transition feeding the first excited state in the daughter nucleus. Our independent results support the conclusion that the large mirror asymmetry is close to the proton halo structure in 26P.


Sign in / Sign up

Export Citation Format

Share Document