Hermetic edge sealing of photovoltaic modules

The feasibility of using an electrostatic bonding (ESB) and ultrasonic welding process to produce hermetic edge seals on terrestrial solar cell modules was investigated. The fabrication sequence is to attach an aluminum foil "gasket' to the perimeter of a glass sheet. A cell circuit is next encapsulated inside the gasket, and its aluminum foil back cover is seam welded ultrasonically to the gasket. An ESB process for sealing aluminum to glass was developed in an ambient air atmosphere, which eliminates the requirement for a vacuum or pressure vessel. An ultrasonic seam welding process was also developed which did not degrade the quality of the ESB seal. Good quality welds with minimal deformation were produced. The effectiveness of the above described sealing techniques was tested by constructing 400 sq cm (8 x 8 s64 sq in) sample modules, and then subjecting them to nondestructive fine and gross leak tests. The gross leak tests identified several different causes of leaks which were then eliminated by modifying the assembly process

Large area space solar cell assemblies

Development of a large area space solar cell assembly is presented. The assembly consists of an ion implanted silicon cell and glass cover. The important attributes of fabrication are (1) use of a back surface field which is compatible with a back surface reflector, and (2) integration of coverglass application and call fabrication

Identification of Mechanosensitive Genes during Embryonic Bone Formation

Although it is known that mechanical forces are needed for normal bone development, the current understanding of how biophysical stimuli are interpreted by and integrated with genetic regulatory mechanisms is limited. Mechanical forces are thought to be mediated in cells by “mechanosensitive” genes, but it is a challenge to demonstrate that the genetic regulation of the biological system is dependant on particular mechanical forces in vivo. We propose a new means of selecting candidate mechanosensitive genes by comparing in vivo gene expression patterns with patterns of biophysical stimuli, computed using finite element analysis. In this study, finite element analyses of the avian embryonic limb were performed using anatomically realistic rudiment and muscle morphologies, and patterns of biophysical stimuli were compared with the expression patterns of four candidate mechanosensitive genes integral to bone development. The expression patterns of two genes, Collagen X (ColX) and Indian hedgehog (Ihh), were shown to colocalise with biophysical stimuli induced by embryonic muscle contractions, identifying them as potentially being involved in the mechanoregulation of bone formation. An altered mechanical environment was induced in the embryonic chick, where a neuromuscular blocking agent was administered in ovo to modify skeletal muscle contractions. Finite element analyses predicted dramatic changes in levels and patterns of biophysical stimuli, and a number of immobilised specimens exhibited differences in ColX and Ihh expression. The results obtained indicate that computationally derived patterns of biophysical stimuli can be used to inform a directed search for genes that may play a mechanoregulatory role in particular in vivo events or processes. Furthermore, the experimental data demonstrate that ColX and Ihh are involved in mechanoregulatory pathways and may be key mediators in translating information from the mechanical environment to the molecular regulation of bone formation in the embryo

Action Recognition with a Bio--Inspired Feedforward Motion Processing Model: The Richness of Center-Surround Interactions

International audienceHere we show that reproducing the functional properties of MT cells with various center--surround interactions enriches motion representation and improves the action recognition performance. To do so, we propose a simplified bio--inspired model of the motion pathway in primates: It is a feedforward model restricted to V1-MT cortical layers, cortical cells cover the visual space with a foveated structure, and more importantly, we reproduce some of the richness of center-surround interactions of MT cells. Interestingly, as observed in neurophysiology, our MT cells not only behave like simple velocity detectors, but also respond to several kinds of motion contrasts. Results show that this diversity of motion representation at the MT level is a major advantage for an action recognition task. Defining motion maps as our feature vectors, we used a standard classification method on the Weizmann database: We obtained an average recognition rate of 98.9%, which is superior to the recent results by Jhuang et al. (2007). These promising results encourage us to further develop bio--inspired models incorporating other brain mechanisms and cortical layers in order to deal with more complex videos

Acceptance-based Behavior Therapy for Depression With Psychosis: Results From a Pilot Feasibility Randomized Controlled Trial

Acceptance-based depression and psychosis therapy (ADAPT), a mindfulness/acceptance-based behavioral activation treatment, showed clinically significant effects in the treatment of depression with psychosis in a previous open trial. The goal of the current study was to further test the feasibility of ADAPT to determine the utility of testing it in a future clinical trial, following a stage model of treatment development. Feasibility was determined by randomizing a small number of patients (N = 13) with comorbid depression and psychosis to medication treatment as usual plus enhanced assessment and monitoring (EAM) versus ADAPT for 4 months of outpatient treatment. Both conditions were deemed acceptable by patients. Differences in between-subjects effect sizes favored ADAPT post-treatment and were in the medium to large range for depression, psychosocial functioning, and experiential avoidance (ie, the target mechanism). Thus ADAPT shows promise for improving outcomes compared to medications alone and requires testing in a fully powered randomized trial

Genetic information: important but not "exceptional"

Much legislation dealing with the uses of genetic information could be criticised for exceptionalising genetic information over other types of information personal to the individual. This paper contends that genetic exceptionalism clouds the issues, and precludes any real debate about the appropriate uses of genetic information. An alternative to “genetically exceptionalist” legislation is to “legislate for fairness”. This paper explores the “legislating for fairness” approach, and concludes that it demonstrates a fundamental misunderstanding of both how legislation is drafted, and how it is interpreted. The uncomfortable conclusion is this: policy-makers and legislators must tackle head-on the difficult policy questions concerning what should and should not be done with genetic information. Only by confronting this crucial issue will they achieve a workable legislative solution to the problems caused by genetic information

Validation of water vapour profiles from the Atmospheric Chemistry Experiment (ACE)

International audienceThe Atmospheric Chemistry Experiment (ACE) mission was launched in August 2003 to sound the atmosphere by solar occultation. Water vapour (H2O), one of the most important molecules for climate and atmospheric chemistry, is one of the key species provided by the two principal instruments, the infrared Fourier Transform Spectrometer (ACE-FTS) and the MAESTRO UV-Visible spectrometer (ACE-MAESTRO). The first instrument performs measurements on several lines in the 1362?2137 cm?1 range, from which vertically resolved H2O concentration profiles are retrieved, from 7 to 90 km altitude. ACE-MAESTRO measures profiles using the water absorption band in the near infrared part of the spectrum at 926.0?969.7 nm. This paper presents a comprehensive validation of the ACE-FTS profiles. We have compared the H2O volume mixing ratio profiles with space-borne (SAGE II, HALOE, POAM III, MIPAS, SMR) observations and measurements from balloon-borne frostpoint hygrometers and a ground based lidar. We show that the ACE-FTS measurements provide H2O profiles with small retrieval uncertainties in the stratosphere (better than 5% from 15 to 70 km, gradually increasing above). The situation is unclear in the upper troposphere, due mainly to the high variability of the water vapour volume mixing ratio in this region. A new water vapour data product from the ACE-MAESTRO (Measurement of Aerosol Extinction in the Stratosphere and Troposphere Retrieved by Occultation) is also presented and initial comparisons with ACE-FTS are discussed

Stresses and strains on the human fetal skeleton during development

Mechanical forces generated by fetal kicks and movements result in stimulation of the fetal skeleton in the form of stress and strain. This stimulation is known to be critical for prenatal musculoskeletal development; indeed, abnormal or absent movements have been implicated in multiple congenital disorders. However, the mechanical stress and strain experienced by the developing human skeleton in utero have never before been characterized. Here, we quantify the biomechanics of fetal movements during the second half of gestation by modelling fetal movements captured using novel cine-magnetic resonance imaging technology. By tracking these movements, quantifying fetal kick and muscle forces, and applying them to three-dimensional geometries of the fetal skeleton, we test the hypothesis that stress and strain change over ontogeny. We find that fetal kick force increases significantly from 20 to 30 weeks' gestation, before decreasing towards term. However, stress and strain in the fetal skeleton rises significantly over the latter half of gestation. This increasing trend with gestational age is important because changes in fetal movement patterns in late pregnancy have been linked to poor fetal outcomes and musculoskeletal malformations. This research represents the first quantification of kick force and mechanical stress and strain due to fetal movements in the human skeleton in utero, thus advancing our understanding of the biomechanical environment of the uterus. Further, by revealing a potential link between fetal biomechanics and skeletal malformations, our work will stimulate future research in tissue engineering and mechanobiology

Validation of OMPS Suomi NPP and OMPS NOAA‐20 Formaldehyde Total Columns With NDACC FTIR Observations

We validate formaldehyde (HCHO) vertical column densities (VCDs) from Ozone Mapping and Profiler Suite Nadir Mapper (OMPS-NM) instruments onboard the Suomi National Polar-orbiting Partnership (Suomi NPP) satellite for 2012–2020 and National Oceanic and Atmospheric Administration-20 (NOAA-20) satellite for 2018–2020, hereafter referred to as OMPS-NPP and OMPS-N20, with ground-based Fourier-Transform Infrared (FTIR) observations of the Network for the Detection of Atmospheric Composition Change (NDACC). OMPS-NPP/N20 HCHO products reproduce seasonal variability at 24 FTIR sites. Monthly variability of OMPS-NPP/N20 has a very good agreement with FTIR, showing correlation coefficients of 0.83 and 0.88, respectively. OMPS-NPP (N20) biases averaged over all sites are −0.9 (4) ± 3 (6)%. However, at clean sites (with VCDs 4.0 × 10$^{15}$ molecules cm$^{−2}$, negative biases of −15% ± 4% appear for OMPS-NPP, but OMPS-N20 shows smaller bias of 0.5% ± 6% due to its smaller ground pixel footprints. Therefore, smaller satellite footprint sizes are important in distinguishing small-scale plumes. In addition, we discuss a bias correction and provide lower limit for the monthly uncertainty of OMPS-NPP/N20 HCHO products. The total uncertainty for OMPS-NPP (N20) at clean sites is 0.7 (0.8) × 10$^{15}$ molecules cm$^{−2}$, corresponding to a relative uncertainty of 32 (30)%. In the case of HCHO VCDs > 4.0 × 10$^{15}$ molecules cm$^{−2}$, however, the relative uncertainty in HCHO VCDs for OMPS-NPP (N20) decreases to 31 (18)%