Implementation of an 8-Core, 64-Thread, Power-Efficient SPARC Server on a Chip

The second in the Niagara series of processors (Niagara2) from Sun Microsystems is based on the power-efficient chip multi-threading (CMT) architecture optimized for Space, Watts (Power), and Performance (SWaP) [SWap Rating = Performance/(Space _* Power) ]. It doubles the throughput performance and performance/watt, and provides >10times improvement in floating point throughput performance as compared to UltraSPARC T1 (Niagara1). There are two 10 Gb Ethernet ports on chip. Niagara2 has eight SPARC cores, each supporting concurrent execution of eight threads for 64 threads total. Each SPARC core has a floating point and graphics unit and an advanced cryptographic unit which provides high enough bandwidth to run the two 10 Gb Ethernet ports encrypted at wire speeds. There is a 4 MB Level2 cache on chip. Each of the four on-chip memory controllers controls two FBDIMM channels. Niagara2 has 503 million transistors on a 342 mm² die packaged in a flip-chip glass ceramic package with 1831 pins. The chip is built in Texas Instruments' 65 nm 11LM triple-Vt CMOS process. It operates at 1.4 GHz at 1.1 V and consumes 84 W.     

Real-world design as a one-semester undergraduate project: example of a robust and low-cost solar lantern

The purpose of this project was to develop a rugged and efficient solar lantern. The lantern was designed to meet the requirements of persons who reside in areas in which access to the electrical grid is limited and whose resources do not permit import of electrical generation capabilities. A representative of a missionary organization operating in Africa developed the original set of specifications for the solar lantern. It will be used by the local school children for doing homework in the evening. These specifications prioritized reliability, ease of operation, rugged construction, portability, and low cost. The resulting design was realized in a single prototype. The design and construction of the prototype was completed as a student/faculty project in the Junior Engineering Clinic course at Rowan University in Glassboro, NJ. It was funded and directed by ETM Solar Works, a New York-based corporation.     

In Vitro Antiamoebic Activity Evaluation and Docking Studies of Metronidazole–Triazole Hybrids

An in‐house database of 520 compounds was docked against Entamoeba histolytica thioredoxin reductase (EhTrR), a promising target for the treatment of amoebiasis. Amongst these, some metronidazole (MTZ)–triazole hybrids were ranked high, with docking scores from ?10.23 to ?7.56. Studies of the binding orientations and conformations show that the head groups of MTZ–triazole hybrids interact with the arginine residues within the binding pocket of EhTrR, making it clear that such is the optimal and most reliable orientation for this class of compounds. The top‐ten MTZ–triazole hybrids were then selected for evaluation of their activity against the HM1:IMSS strain of amoeba. The most active compound, 2‐pyridyl‐(1,2,3‐triazolyl)metronidazole 10 , with an IC₅₀ value of 8.4 nM , was significantly more active than the standard drug MTZ alone. Docking studies revealed that compound 10 may act as an EhTrR inhibitor with activity in the nanomolar range and satisfactory ADME properties; it is a suitable candidate to be carried forward as a potential lead in the discovery of drugs to combat amoebiasis.     

Molecular recognition of the Lewis Y antigen by monoclonal antibodies

The murine monoclonal antibody BR55-2 is directed against thetumor-associated antigen Lewis Y oligosaccharide. The LewisY core antigen is a difucosylated structure consisting of fourhexose units. Analysis of binding profiles of lactoseries isomericstructures by BR55–2 suggest that the binding epitopeincludes the OH-4 and OH-3 groups of the ß-D-galactoseunit, the 6-CH₃ groups of the two fucose units and the N-acetylgroup of the subterminal ß-D-N-acetylglucosamine (ßDGlcNAc).To elucidate the molecular recognition properties of BR55–2for the Y antigen, BR55–2 was cloned, sequenced and itsthree-dimensional structure was examined by molecular modeling.The crystal structure of BR96, another anti-Lewis Y antibody,solved in complex with a nonoate methyl ester Lewis Y tetrasaccharide,and the lectin IV protein in complex with a Lewis b tetrasaccharidecore were used as a guide to probe the molecular basis for BR55–2antigen recognition and specificity. Our modeling study showsthat BR55–2 shares similar recognition features for thedifucosylated type 2 lactoseries Lewis Y structure observedin the BR96-sugar complex. We observe that a major source ofspecificity for the Lewis Y structure by anti-Y antibodies emanatesfrom interaction with the ß-D-N-acetylglucosamineresidue and the nature of the structures extended at the reducingsite of the fucosylated lactosoamine.     

Vartalaap: A distributed multicast communication system

With the increasing proliferation of computer networks and distributed systems, there is a growing number of applications using multicast communication. This paper presents the Vartalaap system developed at IIT, Bombay. Vartalaap is an hierarchical distributed system for multicast communication over a network, implemented in a hardware-independent fashion. The multicast is achieved without resorting to unnecessary broadcasting of messages over the network. Issues covered in this paper include the primitives for multicast, the multicast model and the system architecture. We discuss the implementation of Vartalaap and compare it with some other systems. We conclude with a discussion on the limitations of the current implementation and directions for future work.     

Electrical characteristics and reliability of UV transparent Si/sub 3/N/sub 4/ metal-insulator-metal (MIM) capacitors

In this paper, we discuss the electrical characteristics and reliability of UV transparent Si/sub 3/N/sub 4/ metal-insulator-metal (MIM) capacitors. We examine film thicknesses in the range of 55 to 25 nm with capacitance densities from 1.2 ff//spl mu/m/sup 2/ to 2.8 ff//spl mu/m/sup 2/, respectively, for single MIM capacitors. A new approach for projecting the dielectric reliability of these films extends the limits of maximum operating voltage. Accounting for temperature acceleration and area scaling, the projected lifetimes can be met for a wide range of operating conditions.     

Record bandwidth, spectrally flat coupling with microbend gratings in dispersion-tailored fibers

We demonstrate resonant grating couplers with the broadest bandwidth (565 nm) reported to date, using microbend gratings in dispersion-optimized few-mode fibers. Control of modal dispersion enables the demonstration of spectrally flat (< 0.25-dB ripple) coupling. This enables a compact (1 cm), broad-band (110 nm) variable optical attenuator, which is highly cost-effective, since device assembly simply involves pressing an as-drawn fiber between two corrugated blocks.     

Is 1-hexene epoxidation in TS-1 diffusion limited in different solvents?

PFG NMR diffusion measurements were carried out to determine the effect of solvent on intracrystalline reactant diffusivities and on 1-hexene epoxidation rates in TS-1 catalyst. Using n-hexane in silicalite as a mimic for the TS-1 system, the self-diffusivity of n-hexane in silicalite was found to be 24% higher in methanol solvent than in acetonitrile solvent and 45% higher than in acetone solvent. The presence of trace Al did not affect n-hexane diffusivity. Based on analysis of the Weisz modulus for a slab morphology, the 1-hexene epoxidation reaction in TS-1 was found to be diffusion limited only if the crystal size is at least 38 μm in the methanol system.