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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2004.03.032 Byline: Ying Cao, Jue Zhao, Zhihui Sun, Zhixing Zhao, John Postlethwait, Anming Meng Keywords: Fibroblast growth factor; Mesoderm; Dorsalization; Neuroectoderm; Zebrafish Abstract: Fibroblast growth factors (Fgfs) play important roles in the pattern formation of early vertebrate embryos. We have identified a zebrafish ortholog of human FGF17, named fgf17b. The first phase of fgf17b expression occurs in the blastodermal margin of late blastulae and in the embryonic shield of early gastrulae. The second phase starts after the onset of segmentation, mainly in the presomitic mesoderm and newly formed somites. Injection of fgf17b mRNA into one-cell embryos induces expression of the mesodermal marker no tail (ntl) and rescues ntl expression suppressed by overexpression of lefty1 (lft1). Overexpression of fgf17b dorsalizes zebrafish gastrulae by enhancing expression of chordin (chd), which is an antagonist of the ventralizing signals BMPs. In addition, overexpression of fgf17b posteriorizes the neuroectoderm. Simultaneous knockdown of fgf17b and fgf8 with antisense morpholinos results in reduction of chd and ntl. Knockdown of fgf17b can alleviate inhibitory effect of ectopic expression of fgf3 on otx1. These data together suggest that Fgf17b plays a role in early embryonic patterning. We also demonstrate that fgf17b and fgf8 have stronger mesoderm inducting activity than fgf3, whereas fgf17b and fgf3 have stronger activity in posteriorizing the neuroectoderm than fgf8. Like fgf8, activation of fgf17b expression depends on Nodal signaling. Article History: Received 3 September 2003; Revised 1 March 2004; Accepted 25 March 2004

We have investigated the ability of dsRNA to inhibit gene functions in zebrafish using sequences targeted to the maternal gene pouII-1, the transgene GFP, and an intron of the zebrafish gene terra. We found that embryos injected with all of these dsRNAs at approximately 7.5 pg/embryo or higher had general growth arrest during gastrulation and displayed various nonspecific defects at 24 h postfertilization, although embryonic development was unaffected before the midblastula stage. Reducing dsRNA concentration could alleviate the global defects. Injection of GFP dsRNA (7.5-30 pg/embryo) did not inhibit GFP expression in transgenic fish, although abnormal embryos were induced. Co-injection of GFP mRNA with either GFP or non-GFP dsRNA caused reduction of GFP expression. Whole-mount in situ hybridization clearly showed that embryos injected with dsRNA degraded co-injected and endogenous mRNA without sequence specificity, indicating that dsRNA has a nonspecific effect at the posttranscriptional level. It appears that RNAi is not a viable technique for studying gene function in zebrafish embryos. [C] 2001 Academic Press Key Words: zebrafish; embryos; embryogenesis; RNAi; GFP; double-stranded RNA; mRNA; terra; pouII-1.

In a MOSFET transistor, the subthreshold swing defines the switching efficiency, and the associated slope factor, or so-called body factor, is a critical parameter in charge-based models. However, in an advanced Fully-Depleted Silicon-On-Insulator (FDSOI) process, the slope factor is influenced by a strong back gate coupling due to a thin buried oxide (BOX). A conventional constant expression cannot describe the slope factor at various back-gate voltages. Therefore, this paper proposes a general slope factor expression for front- and back-gate transfer characteristics of long-channel FDSOI MOSFETs in a strong gate coupling. The proposed expression is a continuous function of the surface potential difference between the front and back sides, which explains the slope factor behavior versus the back-gate voltage. Besides, the systematic study is presented for the front/back interface states. The proposed model is applied to evaluate the down-scaling of FDSOI technologies in terms of the gate-coupled slope factor. The scaling in the buried oxide layer degrades the front slope factor, which a thinner channel or a reverse body bias can compensate for at the cost of a higher vertical electric field. Compared to the SiO2 , the application of high- κ dielectric for the buried oxide layer shows a better stand to the degraded slope factor by the interface states. • The model is proposed for subthreshold swing and slope with strong gate coupling. • The reverse body bias shows the efficient enhancement on the subthreshold swing. • The proposed model gives insight into the down-scaling of FDSOI technology. [ABSTRACT FROM AUTHOR]

• Medium thick gate oxide devices with steeper doping profiles on FDSOI. • Enabling gate length scaling and reduce Ron, thus increase Ft and Fmax. • Electron mobility increase due to low channel doping. • Improved switch FoM Coff*Ron/Vmax. In this paper two processes with different source and drain out diffusion into the channel of medium thick gate oxide devices in 22FDX® are compared in terms of HCI reliability (electrical field) and DC/RF performance. The margin to pass HCI reliability of the under-drive device allows a steeper source/drain doping profile which enables further gate length reduction. The steeper doping profile reduces R on significantly while improving the electrostatic behavior due to the longer effective channel. Gate length scaling allows a better trade-off between electrostatic behavior, DC/RF performance, breakdown voltage and reliability. For switch applications the C off *R on,AC /V max figure of merit can be reduced while ft and fmax is increased for power amplifier applications. [ABSTRACT FROM AUTHOR]

• The construction of the artificial SEI layer is realized by a common solvent DMSO. • The components of Li 2 SO 4 and sulfur-containing organic compounds in SEI are helpful to stabilize the lithium anode. • A facile strategy to construct artificial SEI through chemical reaction for lithium metal batteries is proposed. Lithium metal is considered one of the most promising anode materials because of its high theoretical capacity and the lowest electrode potential, but practical application is hampered by high reactivity and volume variation in circulation. As a key component, the artificial solid electrolyte interphase (SEI) is designed to effectively stabilize the lithium anode. Here, the chemical reaction between dimethyl sulfoxide (DMSO) and lithium is accelerated in the presence of potassium hydroxide (KOH). The sulfur-containing organic compounds, lithium sulfate (Li 2 SO 4), lithium hydroxide (LiOH) and other favorable components are introduced into SEI, which enable the modified lithium metal anode to have lower interfacial impedance, higher lithium ion transference number, and more uniform Li-ion deposition. The assembled Li-Li symmetric battery realizes a stable cycle of more than 800 h at a current density of 0.5 mA cm−1 and an areal capacity density of 1 mAh cm−1. The full cell coupled with LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622) still maintains 113 mAh g−1 discharge capacity with 63% capacity retention rate after 400 cycles at a current density of 0.5 C. The simple construction of artificial SEI strategy of this study provides an effective strategy for LMBs with superior electrochemical performance. [Display omitted] [ABSTRACT FROM AUTHOR]

• Parasitic surface conduction of high-resistivity substrates degrades quality factor of inductors. • RF inductors quality factor strongly improves with high-resistivity substrate. • mm-wave inductors need re-design for large gain in quality factor with high-resistivity substrate. The quality factor (Q) of two inductors for 5–60 GHz applications fabricated in an industrial back-end of line (22FDX® from GlobalFoundries) with thick Cu metal layers on top of several Si substrates of different bulk resistivities is analyzed in this paper. The low frequency RF inductor shows an improvement of up to 44% in Q with a high-resistivity substrate. However, no significant improvement is observed for the high-frequency MMW fabricated inductor. This is identified to be due to lower electric field concentration in the substrate due to the small geometry of this MMW inductor that is realized in the top metal Cu layer. Nevertheless, simulations show that a 30% improvement can be achieved with a low loss substrate when designing a MMW inductor as a stacked coil of all BEOL thick metal layers. [ABSTRACT FROM AUTHOR]

• Investigating carrier transport of long/short transistors of 22nm FD-SOI CMOS technology by lowering the temperature and sweeping back-gate voltage. • Intersubband scattering pronouncing at low temperatures that is less significant in short devices due to high ballisticity. • Proposing the ballistic transport as an alternative explanation to the mobility of short devices that is less-enhanced at cryogenic temperatures due to drift-diffusion-based extraction methodology. • Proposing the source-to-drain tunneling as an alternative mechanism that makes subthreshold swing saturate to 30 mV/dec due to a strong drain-to-source voltage. This paper presents an in-depth DC characterization of a 22 nm FDSOI CMOS technology down to deep cryogenic temperature, i.e., 2.95 K. The impact of the back-gate voltage (V back) on device performance, i.e., threshold voltage (V T) and carrier transport, is investigated over a wide temperature range. Moreover, semiclassical and quantum transports of two-dimensional carrier gas are investigated. The effective mobility ( μ eff ) extracted from short devices at cryogenic temperatures is lower than actual mobility due to the presence of ballistic transport. The discontinuous I D –V G is found in both long and extremely short transistors, which is ascribed to the intersubband transition happening during the scattering event. Oscillatory I D –V G due to resonant tunneling manifests itself in short devices at cryogenic temperatures and depends on V back. On the other hand, the worse subthreshold swing is found for short devices in the saturation regime and at cryogenic temperatures due to source-to-drain tunneling. [ABSTRACT FROM AUTHOR]