A manually annotated Actinidia chinensis var. chinensis (kiwifruit) genome highlights the challenges associated with draft genomes and gene prediction in plants

Most published genome sequences are drafts, and most are dominated by computational gene prediction. Draft genomes typically incorporate considerable sequence data that are not assigned to chromosomes, and predicted genes without quality confidence measures. The current Actinidia chinensis (kiwifruit) 'Hongyang' draft genome has 164\ua0Mb of sequences unassigned to pseudo-chromosomes, and omissions have been identified in the gene models

Design and Optimization of SRAM Macro and Logic Using Backside Interconnects at 2nm node

In this work, we explore the resource of backside (BS) interconnect for signal routing in SRAM macro and logic at 2nm technology node to tackle the technology scaling induced frontside (FS) BEOL routing congestion challenge. High-Aspect ratio nano-Through-Silicon-Vias (nTSVs) used as BS to FS metal layers connections have been manufactured with sufficiently low resistance (20 Ohm) and capacitance (0.04fF). Compared to the FS BEOL, the BS routing is very beneficial in improving delay and power efficiency for long interconnect signal routing. Performance and power efficiency improvement up to 44% and 32% respectively is observed using the BS routing for customized SRAM macros (2nm nanosheet, up to 4Mbit) global routing when compared to the FS counterpart. In addition, the BS routing also leads to logic cells (2nm forksheet, extracted from an ARM™ CPU) speed improvement of up to 2.5X and energy efficiency increase of 60% for logic gates driving long interconnect. With capacitance optimization for BS metals, additional 20% performance improvement is observed for SRAM macros and logic cells driving long wirelength.SCOPUS: cp.pinfo:eu-repo/semantics/publishe

Backside PDN and 2.5D MIMCAP to Double Boost 2D and 3D ICs IR-Drop beyond 2nm Node

In this paper, backside power delivery network (BS-PDN) and a high density 2.5D Mimcap (Metal-insulator-metal capacitor) are applied to improve dynamic IR-drop of 2D and 3D ICs at a sub-2nm node. An on-chip PDN design and IR drop modelling framework is proposed and calibrated with the physical design results of 64-bit low power CPU. The calibrated framework is applied to 2D IC PDN with various Mimcap integration and then to 3D IC PDN. The 2.5D Mimcap used here was manufactured with optimized capacitance density of -70 fF/um2. The BSPDN using 2.5D Mimcap has 32.1%/23.5% improvement in IR drop over the no Mimcap/2D Mimcap counterparts respectively, and BSPDN shows 36.3% improvement over the front side PDN (FSPDN) counterpart. Furthermore, by using 2.5D Mimcap + BSPDN in the 3D-IC, the top logic die IR drop is improved by 21.7%.SCOPUS: cp.pinfo:eu-repo/semantics/publishe

Analysis of expressed sequence tags from Actinidia : Applications of a cross species EST database for gene discovery in the areas of flavor, health, color and ripening

Background Kiwifruit (Actinidia spp.) are a relatively new, but economically important crop grown in many different parts of the world. Commercial success is driven by the development of new cultivars with novel consumer traits including flavor, appearance, healthful components and convenience. To increase our understanding of the genetic diversity and gene-based control of these key traits in Actinidia, we have produced a collection of 132,577 expressed sequence tags (ESTs). Results The ESTs were derived mainly from four Actinidia species (A. chinensis, A. deliciosa, A. arguta and A. eriantha) and fell into 41,858 non redundant clusters (18,070 tentative consensus sequences and 23,788 EST singletons). Analysis of flavor and fragrance-related gene families (acyltransferases and carboxylesterases) and pathways (terpenoid biosynthesis) is presented in comparison with a chemical analysis of the compounds present in Actinidia including esters, acids, alcohols and terpenes. ESTs are identified for most genes in color pathways controlling chlorophyll degradation and carotenoid biosynthesis. In the health area, data are presented on the ESTs involved in ascorbic acid and quinic acid biosynthesis showing not only that genes for many of the steps in these pathways are represented in the database, but that genes encoding some critical steps are absent. In the convenience area, genes related to different stages of fruit softening are identified. Conclusion This large EST resource will allow researchers to undertake the tremendous challenge of understanding the molecular basis of genetic diversity in the Actinidia genus as well as provide an EST resource for comparative fruit genomics. The various bioinformatics analyses we have undertaken demonstrates the extent of coverage of ESTs for genes encoding different biochemical pathways in Actinidia