Determining the Spectral Signature of Spatial Coherent Structures

We applied to an open flow a proper orthogonal decomposition (pod) technique, on 2D snapshots of the instantaneous velocity field, to reveal the spatial coherent structures responsible of the self-sustained oscillations observed in the spectral distribution of time series. We applied the technique to 2D planes out of 3D direct numerical simulations on an open cavity flow. The process can easily be implemented on usual personal computers, and might bring deep insights on the relation between spatial events and temporal signature in (both numerical or experimental) open flows.Comment: 4 page

Esophageal cancer-related gene 4 at the interface of injury, inflammation, infection, and malignancy

In humans, esophageal cancer-related gene 4 (ECRG4) is encoded by four exons in the c2orf40 locus of chromosome 2. Translation of ECRG4 messenger ribonucleic acid produces a 148 amino acid-secreted 17 KDa protein that is then processed to 14, ten, eight, six, four, and two KDa peptides, depending on the cell in which the gene is expressed. As hypermethylation at the c2orf40 locus inhibits ECRG4 gene expression in many epithelial cancers, several investigators have speculated that ECRG4 is a candidate tumor suppressor. Indeed, overexpression of ECRG4 inhibits cell proliferation in vitro, but it also has a wide range of effects in vivo beyond its antitumor activity. ECRG4 overexpression affects apoptosis, senescence, cell migration, inflammation, injury, and infection responsiveness. ECRG4 activities also depend on its cellular localization, secretion, and post-translational processing. These cytokine/chemokine-like characteristics argue that ECRG4 is not a traditional candidate tumor suppressor gene, as originally predicted by its downregulation in cancer. We review how insights into the regulation of ECRG4 gene expression, knowledge of its primary structure, and the study of its emerging physiological functions come together to support a much more complex role for ECRG4 at the interface of inflammation, infection, and malignancy

Multiwavelength fluorescence lidar observations of smoke plumes

A five-channel fluorescence lidar was developed for the study of atmospheric aerosol. The fluorescence spectrum induced by 355 nm laser emission is analyzed in five spectral intervals using interference filters. Central wavelengths and the widths of these five interference filters are, respectively, as follows: 438 and 29, 472 and 32, 513 and 29, 560 and 40, and 614 and 54 nm. The relative calibration of these channels has been performed using a tungsten–halogen lamp with a color temperature of 2800 K. This new lidar system was operated during summer–autumn 2022, when strong forest fires occurred in the Moscow region and generated a series of smoke plumes analyzed in this study. Our results demonstrate that, for urban aerosol, the maximal fluorescence backscattering is observed in a 472 nm channel. For the smoke, the maximum is shifted toward longer wavelengths, and the fluorescence backscattering coefficients in 472, 513 and 560 nm channels have comparable values. Thus, from the analysis of the ratios of fluorescence backscattering in available channels, we show that it is possible to identify smoke layers. The particle classification based on single-channel fluorescence capacity (ratio of the fluorescence backscattering to the elastic one) has limitations at high relative humidity (RH). The fluorescence capacity indeed decreases when water uptake of particles enhances the elastic scattering. However, the spectral variation of fluorescence backscattering does not exhibit any dependence on RH and can be therefore applied to aerosol identification.</p

PHOTONS/AERONET sunphotometer network overview. Description – Activities - Results

Fourteenth International Symposium on Atmospheric and Ocean Optics/Atmospheric Physics celebrado del 24 al 30 de junio de 2007 en Buryatia, Russia

Ecrg4 expression and its product augurin in the choroid plexus: impact on fetal brain development, cerebrospinal fluid homeostasis and neuroprogenitor cell response to CNS injury

<p>Abstract</p> <p>Background</p> <p>The content and composition of cerebrospinal fluid (CSF) is determined in large part by the choroid plexus (CP) and specifically, a specialized epithelial cell (CPe) layer that responds to, synthesizes, and transports peptide hormones into and out of CSF. Together with ventricular ependymal cells, these CPe relay homeostatic signals throughout the central nervous system (CNS) and regulate CSF hydrodynamics. One new candidate signal is augurin, a newly recognized 14 kDa protein that is encoded by <it>esophageal cancer related gene-4 </it>(<it>Ecrg4</it>), a putative tumor suppressor gene whose presence and function in normal tissues remains unexplored and enigmatic. The aim of this study was to explore whether <it>Ecrg4 </it>and its product augurin, can be implicated in CNS development and the response to CNS injury.</p> <p>Methods</p> <p><it>Ecrg4 </it>gene expression in CNS and peripheral tissues was studied by <it>in situ </it>hybridization and quantitative RT-PCR. Augurin, the protein encoded by <it>Ecrg4</it>, was detected by immunoblotting, immunohistochemistry and ELISA. The biological consequence of augurin over-expression was studied in a cortical stab model of rat CNS injury by intra-cerebro-ventricular injection of an adenovirus vector containing the <it>Ecrg4 </it>cDNA. The biological consequences of reduced augurin expression were evaluated by characterizing the CNS phenotype caused by <it>Ecrg4 </it>gene knockdown in developing zebrafish embryos.</p> <p>Results</p> <p>Gene expression and immunohistochemical analyses revealed that, the CP is a major source of <it>Ecrg4 </it>in the CNS and that <it>Ecrg4 </it>mRNA is predominantly localized to choroid plexus epithelial (CPe), ventricular and central canal cells of the spinal cord. After a stab injury into the brain however, both augurin staining and <it>Ecrg4 </it>gene expression decreased precipitously. If the loss of augurin was circumvented by over-expressing <it>Ecrg4 in vivo</it>, BrdU incorporation by cells in the subependymal zone decreased. Inversely, gene knockdown of <it>Ecrg4 </it>in developing zebrafish embryos caused increased proliferation of GFAP-positive cells and induced a dose-dependent hydrocephalus-like phenotype that could be rescued by co-injection of antisense morpholinos with <it>Ecrg4 </it>mRNA.</p> <p>Conclusion</p> <p>An unusually elevated expression of the <it>Ecrg4 </it>gene in the CP implies that its product, augurin, plays a role in CP-CSF-CNS function. The results are all consistent with a model whereby an injury-induced decrease in augurin dysinhibits target cells at the ependymal-subependymal interface. We speculate that the ability of CP and ependymal epithelium to alter the progenitor cell response to CNS injury may be mediated, in part by <it>Ecrg4</it>. If so, the canonic control of its promoter by DNA methylation may implicate epigenetic mechanisms in neuroprogenitor fate and function in the CNS.</p

Long-range-transported Canadian smoke plumes in the lower stratosphere over northern France

Long-range-transported Canadian smoke layers in the stratosphere over northern France were detected by three lidar systems in August 2017. The peaked optical depth of the stratospheric smoke layer exceeds 0.20 at 532&thinsp;nm, which is comparable with the simultaneous tropospheric aerosol optical depth. The measurements of satellite sensors revealed that the observed stratospheric smoke plumes were transported from Canadian wildfires after being lofted by strong pyro-cumulonimbus. Case studies at two observation sites, Lille (lat 50.612, long 3.142, 60&thinsp;m&thinsp;a.s.l.) and Palaiseau (lat 48.712, long 2.215, 156&thinsp;m&thinsp;a.s.l.), are presented in detail. Smoke particle depolarization ratios are measured at three wavelengths: over 0.20 at 355&thinsp;nm, 0.18–0.19 at 532&thinsp;nm, and 0.04–0.05 at 1064&thinsp;nm. The high depolarization ratios and their spectral dependence are possibly caused by the irregular-shaped aged smoke particles and/or the mixing with dust particles. Similar results are found by several European lidar stations and an explanation that can fully resolve this question has not yet been found. Aerosol inversion based on lidar 2α+3β data derived a smoke effective radius of about 0.33&thinsp;µm for both cases. The retrieved single-scattering albedo is in the range of 0.8 to 0.9, indicating that the smoke plumes are absorbing. The absorption can cause perturbations to the temperature vertical profile, as observed by ground-based radiosonde, and it is also related to the ascent of the smoke plumes when exposed in sunlight. A direct radiative forcing (DRF) calculation is performed using the obtained optical and microphysical properties. The calculation revealed that the smoke plumes in the stratosphere can significantly reduce the radiation arriving at the surface, and the heating rate of the plumes is about 3.5&thinsp;K&thinsp;day−1. The study provides a valuable characterization for aged smoke in the stratosphere, but efforts are still needed in reducing and quantifying the errors in the retrieved microphysical properties as well as radiative forcing estimates.</p

Interiorized Feminism and Gendered Nostalgia of The ‘Daughter Generation’ in Ning Ying's Perpetual Motion

This is the author's accepted manuscript. The original publication is available at http://dx.doi.org/10.1386/jcc.5.3.253_1Ning Ying’s 2006 film Wuqiong dong/Perpetual Motion can be regarded as her first attempt to explore the genre of ‘women’s film’. Deviating from her previous neo-realist style, this film seeks to cultivate an alternative cinematic practice through developing a heavy-handed negative aesthetics. Ning Ying interiorizes the filmic exploration of female subjectivity in an enclosed time and space, which is constantly haunted by a spectral aesthetics characterized by audio-visual allusions to loss, grave, ruins and ghosts. However, the film’s radical content and alternative aesthetics are, ironically, packaged in prevailing consumer aesthetics and commodity fetishism on and off the silver screen. All these competing drives and accounts render the film a contested narrative constantly oscillating between avant-garde feminism and domestic melodrama, and between a register of disintegrating sisterhood and a celebrity scandal of adultery. This article examines the discursive and aesthetic innovations, contradictions and limits of Ning Ying’s cinematic feminism

Overview of the Chemistry-Aerosol Mediterranean Experiment/Aerosol Direct Radiative Forcing on the Mediterranean Climate (ChArMEx/ADRIMED) summer 2013 campaign

The Chemistry-Aerosol Mediterranean Experiment (ChArMEx; http://charmex.lsce.ipsl.fr) is a collaborative research program federating international activities to investigate Mediterranean regional chemistry-climate interactions. A special observing period (SOP-1a) including intensive airborne measurements was performed in the framework of the Aerosol Direct Radiative Impact on the regional climate in the MEDiterranean region (ADRIMED) project during the Mediterranean dry season over the western and central Mediterranean basins, with a focus on aerosol-radiation measurements and their modeling. The SOP-1a took place from 11 June to 5 July 2013. Airborne measurements were made by both the ATR-42 and F-20 French research aircraft operated from Sardinia (Italy) and instrumented for in situ and remote-sensing measurements, respectively, and by sounding and drifting balloons, launched in Minorca. The experimental setup also involved several ground-based measurement sites on islands including two ground-based reference stations in Corsica and Lampedusa and secondary monitoring sites in Minorca and Sicily. Additional measurements including lidar profiling were also performed on alert during aircraft operations at EARLINET/ACTRIS stations at Granada and Barcelona in Spain, and in southern Italy. Remote-sensing aerosol products from satellites (MSG/SEVIRI, MODIS) and from the AERONET/PHOTONS network were also used. Dedicated meso-scale and regional modeling experiments were performed in relation to this observational effort. We provide here an overview of the different surface and aircraft observations deployed during the ChArMEx/ADRIMED period and of associated modeling studies together with an analysis of the synoptic conditions that determined the aerosol emission and transport. Meteorological conditions observed during this campaign (moderate temperatures and southern flows) were not favorable to producing high levels of atmospheric pollutants or intense biomass burning events in the region. However, numerous mineral dust plumes were observed during the campaign, with the main sources located in Morocco, Algeria and Tunisia, leading to aerosol optical depth (AOD) values ranging between 0.2 and 0.6 (at 440 nm) over the western and central Mediterranean basins. One important point of this experiment concerns the direct observations of aerosol extinction onboard the ATR-42, using the CAPS system, showing local maxima reaching up to 150Mm(-1) within the dust plume. Non-negligible aerosol extinction (about 50Mm(-1)) has also been observed within the marine boundary layer (MBL). By combining the ATR- 42 extinction coefficient observations with absorption and scattering measurements, we performed a complete optical closure revealing excellent agreement with estimated optical properties. This additional information on extinction properties has allowed calculation of the dust single scattering albedo (SSA) with a high level of confidence over the western Mediterranean. Our results show a moderate variability from 0.90 to 1.00 (at 530 nm) for all flights studied compared to that reported in the literature on this optical parameter. Our results underline also a relatively low difference in SSA with values derived near dust sources. In parallel, active remote-sensing observations from the surface and onboard the F-20 aircraft suggest a complex vertical structure of particles and distinct aerosol layers with sea spray and pollution located within the MBL, and mineral dust and/or aged North American smoke particles located above (up to 6–7 km in altitude). Aircraft and balloon-borne observations allow one to investigate the vertical structure of the aerosol size distribution showing particles characterized by a large size (> 10 μm in diameter) within dust plumes. In most of cases, a coarse mode characterized by an effective diameter ranging between 5 and 10 μm, has been detected above the MBL. In terms of shortwave (SW) direct forcing, in situ surface and aircraft observations have been merged and used as inputs in 1-D radiative transfer codes for calculating the aerosol direct radiative forcing (DRF). Results show significant surface SW instantaneous forcing (up to (-90)Wm(-2) at noon). Aircraft observations provide also original estimates of the vertical structure of SW and LW radiative heating revealing significant instantaneous values of about 5 K per day in the solar spectrum (for a solar angle of 30 ) within the dust layer. Associated 3-D modeling studies from regional climate (RCM) and chemistry transport (CTM) models indicate a relatively good agreement for simulated AOD compared with observations from the AERONET/PHOTONS network and satellite data, especially for long-range dust transport. Calculations of the 3-D SW (clear-sky) surface DRF indicate an average of about -10 to -20Wm(-2) (for the whole period) over the Mediterranean Sea together with maxima (-50Wm(-2)) over northern Africa. The top of the atmosphere (TOA) DRF is shown to be highly variable within the domain, due to moderate absorbing properties of dust and changes in the surface albedo. Indeed, 3-D simulations indicate negative forcing over the Mediterranean Sea and Europe and positive forcing over northern Africa. Finally, a multiyear simulation, performed for the 2003 to 2009 period and including an ocean–atmosphere (O–A) coupling, underlines the impact of the aerosol direct radiative forcing on the sea surface temperature, O–A fluxes and the hydrological cycle over the Mediterranean.French National Research Agency (ANR) ANR-11-BS56-0006ADEMEFrench Atomic Energy CommissionCNRS-INSU and Meteo-France through the multidisciplinary programme MISTRALS (Mediterranean Integrated Studies aT Regional And Local Scales)CORSiCA project - Collectivite Territoriale de Corse through Fonds Europeen de Developpement Regional of the European Operational ProgramContrat de Plan Etat-RegionEuropean Union's Horizon 2020 research and innovation program 654169Spanish Ministry of Economy and Competitivity TEC2012-34575Science and Innovation UNPC10-4E-442European Union (EU)Department of Economy and Knowledge of the Catalan Autonomous Government SGR 583Andalusian Regional Government P12-RNM-2409Spanish Government CGL2013-45410-R 26225

Esophageal Cancer Related Gene-4 Is a Choroid Plexus-Derived Injury Response Gene: Evidence for a Biphasic Response in Early and Late Brain Injury

By virtue of its ability to regulate the composition of cerebrospinal fluid (CSF), the choroid plexus (CP) is ideally suited to instigate a rapid response to traumatic brain injury (TBI) by producing growth regulatory proteins. For example, Esophageal Cancer Related Gene-4 (Ecrg4) is a tumor suppressor gene that encodes a hormone-like peptide called augurin that is present in large concentrations in CP epithelia (CPe). Because augurin is thought to regulate senescence, neuroprogenitor cell growth and differentiation in the CNS, we evaluated the kinetics of Ecrg4 expression and augurin immunoreactivity in CPe after CNS injury. Adult rats were injured with a penetrating cortical lesion and alterations in augurin immunoreactivity were examined by immunohistochemistry. Ecrg4 gene expression was characterized by in situ hybridization. Cell surface augurin was identified histologically by confocal microscopy and biochemically by sub-cellular fractionation. Both Ecrg4 gene expression and augurin protein levels were decreased 24–72 hrs post-injury but restored to uninjured levels by day 7 post-injury. Protein staining in the supraoptic nucleus of the hypothalamus, used as a control brain region, did not show a decrease of auguin immunoreactivity. Ecrg4 gene expression localized to CPe cells, and augurin protein to the CPe ventricular face. Extracellular cell surface tethering of 14 kDa augurin was confirmed by cell surface fractionation of primary human CPe cells in vitro while a 6–8 kDa fragment of augurin was detected in conditioned media, indicating release from the cell surface by proteolytic processing. In rat CSF however, 14 kDa augurin was detected. We hypothesize the initial release and proteolytic processing of augurin participates in the activation phase of injury while sustained Ecrg4 down-regulation is dysinhibitory during the proliferative phase. Accordingly, augurin would play a constitutive inhibitory function in normal CNS while down regulation of Ecrg4 gene expression in injury, like in cancer, dysinhibits proliferation

Parental and infant characteristics and childhood leukemia in Minnesota

<p>Abstract</p> <p>Background</p> <p>Leukemia is the most common childhood cancer. With the exception of Down syndrome, prenatal radiation exposure, and higher birth weight, particularly for acute lymphoid leukemia (ALL), few risk factors have been firmly established. Translocations present in neonatal blood spots and the young age peak of diagnosis suggest that early-life factors are involved in childhood leukemia etiology.</p> <p>Methods</p> <p>We investigated the association between birth characteristics and childhood leukemia through linkage of the Minnesota birth and cancer registries using a case-cohort study design. Cases included 560 children with ALL and 87 with acute myeloid leukemia (AML) diagnoses from 28 days to 14 years. The comparison group was comprised of 8,750 individuals selected through random sampling of the birth cohort from 1976–2004. Cox proportional hazards regression specific for case-cohort studies was used to compute hazard ratios (HR) and 95% confidence intervals (CIs).</p> <p>Results</p> <p>Male sex (HR = 1.41, 95% CI 1.16–1.70), white race (HR = 2.32, 95% CI 1.13–4.76), and maternal birth interval ≥ 3 years (HR = 1.31, 95% CI 1.01–1.70) increased ALL risk, while maternal age increased AML risk (HR = 1.21/5 year age increase, 95% CI 1.0–1.47). Higher birth weights (>3798 grams) (HRALL = 1.46, 1.08–1.98; HRAML = 1.97, 95% CI 1.07–3.65), and one minute Apgar scores ≤ 7 (HRALL = 1.30, 95% CI 1.05–1.61; HRAML = 1.62, 95% CI 1.01–2.60) increased risk for both types of leukemia. Sex was not a significant modifier of the association between ALL and other covariates, with the exception of maternal education.</p> <p>Conclusion</p> <p>We confirmed known risk factors for ALL: male sex, high birth weight, and white race. We have also provided data that supports an increased risk for AML following higher birth weights, and demonstrated an association with low Apgar scores.</p