Opposite direction multiple-phase clocking in adjacent CCD shift registers

Parallelled charge transfer channels have multiple-phase-clocked gate electrodes overspanning them in one of a number of arrangements conditioning the transfer of charge packets in opposing directions in adjacent charge transfer channels. Three-phase, four-phase, five-phase and six-phase clocking arrangements constructed in three layers of polysilicon embody the invention

Method of making a semiconductor device

There is disclosed herein a method of making a device made up of at least two separate parts each of which is formed of a patterned array with the parts being mounted one on the other, with the patterned arrays of the parts being aligned, such as a CCD imager having a color filter thereon. The two parts are made on separate substrates with a first alignment key being formed on each substrate. The first alignment keys are formed by photolithography using the same mask to form the first alignment keys on each substrate. The various features of each of the parts are then formed on each substrate with each feature being formed by a photolithographic step using a mask which is aligned to a first alignment key so as to align all the features. A second alignment key is formed on each substrate and is positioned on each substrate in the same relationship with a first alignment key. The second alignment keys are of a material and construction so as to be visible when radiation of a desired wavelength is directed through the substrates. A part formed on one of the substrates is placed over a part formed on the other substrate. Radiation is directed through the substrates and the second alignment keys are aligned so as to align the patterned array of the two parts

High density Schottky barrier IRCCD sensors for SWIR applications at intermediate temperature

Monolithic 32 x 64 and 64 x 1:128 palladium silicide (Pd2Si) interline transfer infrared charge coupled devices (IRCCDs) sensitive in the 1 to 3.5 micron spectral band were developed. This silicon imager exhibits a low response nonuniformity of typically 0.2 to 1.6% rms, and was operated in the temperature range between 40 to 140 K. Spectral response measurements of test Pd2Si p-type Si devices yield quantum efficiencies of 7.9% at 1.25 microns, 5.6% at 1.65 microns 2.2% at 2.22 microns. Improvement in quantum efficiency is expected by optimizing the different structural parameters of the Pd2Si detectors. The spectral response of the Pd2Si detectors fit a modified Fowler emission model. The measured photo-electric barrier height for the Pd2Si detectors is 0.34 eV and the measured quantum efficiency coefficient, C1, is 19%/eV. The dark current level of Pd2Si Schottky barrier focal plane arrays (FPAs) is sufficiently low to enable operation at intermediate temperatures at TV frame rates. Typical dark current level measured at 120 K on the FPA is 2 nA/sq cm. The operating temperature of the Pd2Si FPA is compatible with passive cooler performance. In addition, high density Pd2Si Schottky barrier FPAs are manufactured with high yield and therefore represent an economical approach to short wavelength IR imaging. A Pd2Si Schottky barrier image sensor for push-broom multispectral imaging in the 1.25, 1.65, and 2.22 micron bands is being studied. The sensor will have two line arrays (dual band capability) of 512 detectors each, with 30 micron center-to-center detector spacing. The device will be suitable for chip-to-chip abutment, thus providing the capability to produce large, multiple chip focal planes with contiguous, in-line sensors

DNA methyltransferase-3-dependent nonrandom template segregation in differentiating embryonic stem cells.

Asymmetry of cell fate is one fundamental property of stem cells, in which one daughter cell self-renews, whereas the other differentiates. Evidence of nonrandom template segregation (NRTS) of chromosomes during asymmetric cell divisions in phylogenetically divergent organisms, such as plants, fungi, and mammals, has already been shown. However, before this current work, asymmetric inheritance of chromatids has never been demonstrated in differentiating embryonic stem cells (ESCs), and its molecular mechanism has remained unknown. Our results unambiguously demonstrate NRTS in asymmetrically dividing, differentiating human and mouse ESCs. Moreover, we show that NRTS is dependent on DNA methylation and on Dnmt3 (DNA methyltransferase-3), indicating a molecular mechanism that regulates this phenomenon. Furthermore, our data support the hypothesis that retention of chromatids with the old template DNA preserves the epigenetic memory of cell fate, whereas localization of new DNA strands and de novo DNA methyltransferase to the lineage-destined daughter cell facilitates epigenetic adaptation to a new cell fate

Edge passivated charge-coupled device image sensor

A charge-coupled device (CCD) image sensor includes in a substrate of single crystalline silicon of one conductivity type an array of a plurality of spaced, parallel channel regions of the opposite conductivity type extending along one major surface of the substrate. A plurality of parallel conductive gates are over the one major surface of the substrate and extend transversely across the channel regions. The outermost channel regions of the array are positioned adjacent edges of the substrate so that a plurality of the image sensors can be mounted in edge-to-edge relation with the channel regions of the various sensors being close together. The sensor includes passivating means between each outermost channel region and the adjacent edge to prevent charge carriers generated by the edge from being injected into the outermost channel region. The passivating means includes a highly conductive drain region of a conductivity type opposite to that of the substrate within the substrate and extending along the one major surface between the outermost channel region and the edge. Also, a highly conductive region of the same conductivity type as the substrate is on the substrate and extends along the one major surface directly at the edge

Oxytocin is an age-specific circulating hormone that is necessary for muscle maintenance and regeneration.

The regenerative capacity of skeletal muscle declines with age. Previous studies suggest that this process can be reversed by exposure to young circulation; however, systemic age-specific factors responsible for this phenomenon are largely unknown. Here we report that oxytocin--a hormone best known for its role in lactation, parturition and social behaviours--is required for proper muscle tissue regeneration and homeostasis, and that plasma levels of oxytocin decline with age. Inhibition of oxytocin signalling in young animals reduces muscle regeneration, whereas systemic administration of oxytocin rapidly improves muscle regeneration by enhancing aged muscle stem cell activation/proliferation through activation of the MAPK/ERK signalling pathway. We further show that the genetic lack of oxytocin does not cause a developmental defect in muscle but instead leads to premature sarcopenia. Considering that oxytocin is an FDA-approved drug, this work reveals a potential novel and safe way to combat or prevent skeletal muscle ageing

Expression screening using a Medaka cDNA library identifies evolutionarily conserved regulators of the p53/Mdm2 pathway

Background: The p53 tumor suppressor protein is mainly regulated by alterations in the half-life of the protein, resulting in significant differences in p53 protein levels in cells. The major regulator of this process is Mdm2, which ubiquitinates p53 and targets it for proteasomal degradation. This process can be enhanced or reduced by proteins that associate with p53 or Mdm2 and several proteins have been identified with such an activity. Furthermore, additional ubiquitin ligases for p53 have been identified in recent years. Nevertheless, our understanding of how p53 abundance and Mdm2 activity are regulated remains incomplete. Here we describe a cell culture based overexpression screen to identify evolutionarily conserved regulators of the p53/Mdm2 circuit. The results from this large-scale screening method will contribute to a better understanding of the regulation of these important proteins. Methods: Expression screening was based on co-transfection of H1299 cells with pools of cDNA’s from a Medaka library together with p53, Mdm2 and, as internal control, Ror2. After cell lysis, SDS-PAGE/WB analysis was used to detect alterations in these proteins. Results: More than one hundred hits that altered the abundance of either p53, Mdm2, or both were identified in the primary screen. Subscreening of the library pools that were identified in the primary screen identified several potential novel regulators of p53 and/or Mdm2. We also tested whether the human orthologues of the Medaka genes regulate p53 and/or Mdm2 abundance. All human orthologues regulated p53 and/or Mdm2 abundance in the same manner as the proteins from Medaka, which underscores the suitability of this screening methodology for the identification of new modifiers of p53 and Mdm2. Conclusions: Despite enormous efforts in the last two decades, many unknown regulators for p53 and Mdm2 abundance are predicted to exist. This cross-species approach to identify evolutionarily conserved regulators demonstrates that our Medaka unigene cDNA library represents a powerful tool to screen for these novel regulators of the p53/Mdm2 pathway

Delay in development and behavioural abnormalities in the absence of p53 in zebrafish

p53 is well-known for its tumour-suppressive activity. However, in the past decade it became clear that p53 is also involved in other processes including stem cell proliferation, differentiation and animal development. To investigate the role of p53 in early embryonic development, we targeted p53 by CRISPR/Cas9 to make a p53 knock-out zebrafish (Danio rerio). Our data show developmental and behavioural effects in p53-deficient zebrafish embryos and larvae. Specifically, we found that early development of zebrafish was clearly delayed in the absence of p53. However, after 1 day (1 dpf), the p53-deficient embryos appeared to recover, as evidenced by a similar level of pigmentation at 26 hpf, similar size of the eye at 4 dpf and only a minor difference in body size at 4 dpf compared to p53 wild-type siblings. The recovery of development after 1 dpf in p53-deficient embryos could be due to a compensatory mechanism involving other p53 family members. p63 and p73 were found over-expressed with respect to wild-type siblings. However, despite this adaptation, the hatching time remained delayed in p53-/- zebrafish. In addition to differences in development, p53-null zebrafish embryos also showed differences in behaviour. We observed an overall reduced activity and a reduced travel distance under non-stressed conditions and after exposing the larvae to vibration. We also observed a longer latency until the larvae started to move after touching with a needle. Overall, these data indicate that p53 is involved in early development and locomotion activities.</p

Credibility of online political news among Egyptian youth

This study confirms previous literature discoveries that perceived credibility of medium, source and message have a direct influence on the perceived credibility of online political news. Each credibility factor is examined separately to identify its influence and strength on the dependent variable. Medium credibility, Internet, is considered the factor that has the strongest influence on perceived credibility of online political news, followed by the source then finally message of online political news. Consumption of online political news has also a direct influence on perception of credibility of online political news but to a much lesser extent. Timely coverage, freedom of speech and dynamic representation are Internet’s inherent features and are highly recognized by Egyptian youth as credibility factors. As for other credibility factors related to believability, objectivity and balance youth become more skeptical about credibility of online political news. Many reasons led to this doubtful view but the most apparent reason in this study is attributed to the abuse of Internet as a communication tool for online political news and lack of regulation. Hence, the uncontrollable freedom of publishing and commenting on political news stories by average citizens who could be politically ignorant, with personal agendas and without any media knowledge