The design of optical systems for digital cameras is complicated by the requirement that the image surface be planar, which results in complex and expensive optics. We analyze a compact optical system with a curved image surface and compare its performance to systems with planarimage surfaces via optics analysis and image system simulation. Our analysis shows that a curved image surface provides a way to lower the number of optical elements, reduce aberrations including astigmatism and coma, and increase off-axis brightness and sharpness. A method to fabricate curved image focal plane arrays using monolithic silicon is demonstrated.

Despite progress in the performance of image sensors, comparatively little work has focused on overcoming the limitations of planar image sensor arrays. We present a technique to construct curved monolithic silicon structures that can be processed using standard silicon processing prior to curving. The process relies on microstructuring of a monolithic silicon die using a deep reactive ion etch process. This technique can be used to build curved integrated circuits such as image sensors for more compact cameras with improved optical performance.

Our earlier studies had suggested that endonuclease G (EndoG), a member of the evolutionarily conserved DNA͞RNA nonspecific ␤␤␣-Me-finger nuclease family, functioned in the a sequencemediated segment inversion observed during herpes simplex virus 1 replication. To test this hypothesis, we used RNA interference to reduce the level of EndoG in mammalian cells in culture. Reduction of EndoG produced a small but statistically significant decrease in a sequence-mediated recombination, suggesting that EndoG does play a role in this process. We also observed that reduction in the level of EndoG resulted in a deficiency in cell proliferation. Cells with a reduced level of EndoG also showed changes in cell distribution in the cell cycle, producing a pattern characteristic of cells that have been arrested in the G2 phase. These findings suggest that EndoG is required for normal cellular proliferation.herpes simplex virus 1 ͉ short hairpin RNA ͉ cell cycle ͉ nuclease ͉ HSV-1 a sequence E ndonuclease G (EndoG) belongs to a group of conserved, DNA͞RNA nonspecific ␤␤␣-metal-ion-finger nucleases (1). In the mouse, EndoG is expressed in the cytoplasm as a precursor of Ϸ33 kDa, which is converted into the mature form of Ϸ28 kDa when it enters the mitochondria (2). EndoG is capable of digesting double-and single-stranded DNA and DNA⅐RNA heteroduplexes (2-5). With double-stranded DNA as substrate, EndoG first generates single-stranded breaks preferentially in (dG) n ⅐(dC) n homopolymer sequences followed by double-stranded breaks (3, 6, 7). EndoG also generates double-stranded breaks in R loops (7) and cleaves DNA with cisplatin-mediated damage (8). Although EndoG is present predominantly in the intermembrane space of mitochondria (7,9,10), it is also found in the nucleus (2, 11). It has been suggested that EndoG functions in mitochondrial DNA synthesis (2) and apoptosis (10, 12). However, its role in those cellular functions remains controversial, as does its requirement for cell viability (9).Our interest in EndoG originated in our studies of the genomic inversion that occurs during herpes simplex virus 1 (HSV-1) DNA replication. The HSV-1 genome consists of a linear 152-kb double-stranded DNA comprising two unique segments, L and S (13). The HSV-1 a sequence, a recombinogenic sequence containing 83% GϩC (14,15), is present as a direct repeat at the two termini of the viral genome and as an inverted repeat at the junction of L and S. Breakage at the HSV-1 a sequence is believed to trigger a recombination reaction resulting in inversion of the L and the S segments, producing the four possible isomers (16-18). In a previous study, we purified EndoG from HeLa cell nuclei and demonstrated that under our experimental conditions, EndoG is the only cellular enzyme capable of generating double-stranded breaks at the HSV-1 a sequence (6). We therefore hypothesized that EndoG initiates the recombinational event that triggers HSV-1 segment inversion. In this study, we tested this hypothesis by using RNA interference to reduce the cellular ...

Using a large sample of 26 623 quasars with redshifts in the range 1.5 ≤ z ≤ 5.1 with C IV λ1549 Å emission line in Fifth Data Release of the Sloan Digital Sky Survey (SDSS), we investigate the cosmological evolution of the Baldwin effect, i.e. the relation between the equivalent width (EW) of the C IV emission line and continuum luminosity. We confirm the earlier result that there exists a strong correlation between the C IV EW and the continuum luminosity, and we find that, up to z ≈ 5, the slope of the Baldwin effect seems to have no effect of cosmological evolution. A subsample of 13 960 quasars with broad C IV λ1549 Å emission line from SDSS is used to explore the origin of the Baldwin effect. We find that C IV EW have a strong correlation with the mass of supermassive black hole (SMBH), and a weak correlation with the Eddington ratio, L Bol /L Edd . This suggests that the SMBH mass is probably the primary drive for the Baldwin effect.

A coculture system that routinely produces a group of cells from adult peripheral blood is presented. A subset of CD45− cells with a fibroblastic morphology was isolated. The CD45− fibroblastic cells are the first peripheral blood‐derived cells that fulfill the criteria of mesenchymal stem cells as defined by the International Society for Cellular Therapy.

unrolls last and is given by imax=t/D, where t is the thickness of the spiral ribbon defined by the fabrication process and D We have developed an approach to build large-area electronics the diameter of the innermost spiral winding (Fig. 3). For from monolithic silicon integrated circuits. The method used t=2gm, and assuming a maximum allowable strain of Fax=1%, deep reactive ion etching to structure a monolithic silicon a minimum node diameter of D=200m is required. If finer substrate into a stretchable, two-dimensional, wired network lithography is used to define thinner ribbons, the silicon that can be expanded to cover large planar or curved surfaces islands can be shrunk proportionally. In Fig. 4, a typical force to realize high-performance, large-area, monolithic silicon vs. displacement calculated using finite-element simulations electronics in a cost-effective manner. This approach has ( Fig. 3) is shown. The length of the spiral ribbon can be applications in sensing, smart materials, electronic textile, adjusted depending on the desired density of silicon after RFID tag and microconcentrator solar cell manufacturing.stretching.

Using the properties of the quasi-stellar object (QSO) catalogue of Shen et al., from the Seventh Data Release of the Sloan Digital Sky Survey, we investigate the Baldwin effect, its slope evolution, and the underlying drive for a large sample of 35 019 QSOs with reliable spectral analysis. We find that the Baldwin effect exists in this large sample of QSOs, and that it is almost the same in 11 different redshift bins, up to z ∼ 5. The slope is −0.238 using the bivariate correlated errors and intrinsic scatter (BCES) algorithm -the equivalent width (EW) of C IV depends on the continuum -and −0.787 using the BCES bisector. For 11 redshift bins, there is an increase in the slope of the Baldwin effect from z ∼ 1.5 to z ∼ 2.0. From z ∼ 2.0 to z ∼ 5.0, the change in the slope is not clear, considering the uncertainties or larger redshift bins. There is a strong correlation between the rest-frame C IV EW and the C IV-based M BH , while the relation between the C IV EW and the Mg II-based M BH is very weak. With the correction of the C IV-based M BH from the C IV blueshift relative to Mg II, we suggest that this strong correlation is a result of the bias of the C IV-based M BH , with respect to that from the Mg II line. Considering the Mg II-based M BH , a medium strong correlation is found between the C IV EW and the Eddington ratio, which implies that the Eddington ratio seems to be a better underlying physical parameter than the central black hole mass.

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