The quest for efficiency improvement raises questions regarding the optimal air temperature for data centers. The ASHRAE TC-9.9 committee has recently adopted an extension of the recommended thermal envelope for server inlet temperature and humidity. A popular hypothesis suggests that total energy demands should diminish as the server inlet temperatures increase. This paper tests that hypothesis through the development of a composite power consumption baseline for a mixture of servers as a function of inlet temperature and applying this data to a variety of cooling architectures.

Download white paper

The trend of increasing heat densities in data centers has held consistent with advances in computing technology for many years. As power density increased, it became evident that the degree of difficulty in cooling these higher power demand loads was also increasing. In recent years, traditional cooling system design has proven inadequate to remove concentrated heat loads (up to and greater than 20 kW per rack). This has driven an architectural shift in data center cooling. The advent of a newer cooling architecture that was designed for the higher densities has brought with it increased efficiencies for the data center. This article discusses the efficiency benefits of row-based cooling compared to two other common cooling architectures.

Download white paper

Traditional methodologies for monitoring the data center environment are no longer sufficient. With technologies such as blade servers driving up cooling demands and regulations such as Sarbanes-Oxley driving up data security requirements, the physical environment in the data center must be watched more closely. While well understood protocols exist for monitoring physical devices such as UPS systems, computer room air conditioners, and fire suppression systems, there is a class of distributed monitoring points that is often ignored. This paper describes this class of threats, suggests approaches to deploying monitoring devices, and provides best practices in leveraging the collected data to reduce downtime.

Download white paper

High-density servers offer a significant performance per watt benefit. However, depending on the deployment, they can present a significant cooling challenge. Vendors are now designing servers that can demand over 40 kW of cooling per rack. With most data centers designed to cool an average of no more than 2 kW per rack, innovative strategies must be used for proper cooling of high-density equipment. This paper provides ten approaches for increasing cooling efficiency, cooling capacity, and power density in existing data centers.

Download white paper

Despite advances in computer technology, power outages continue to be a major cause of PC and server downtime. Protecting computer systems with Uninterruptible Power Supply (UPS) hardware is part of a total solution, but power management software is also necessary to prevent data corruption after extended power outages. Various software configurations are discussed, and best practices aimed at ensuring uptime are presented.

Download white paper

Whether you are evaluating static analysis in your development cycle or already using static analysis today, learn what every development team needs to know, including what to look for when evaluating static analysis solutions, how to minimize the risk that noise and false positive rates pose to successful deployments, how to measure and report on quality, and ease of adoption. Includes live demonstration of Coverity Prevent, the static analysis solution of choice for scanning billions of lines of mission-critical code at over 600 companies and government agencies worldwide.

View webcast

[via UC Berkeley Press Release]
By Robert Sanders, Media Relations | 08 December 2009

BERKELEY — The 2009 H1N1 influenza virus used a new strategy to cross from birds into humans, a warning that it has more than one trick up its sleeve to jump the species barrier and become virulent.

The sequence of the three subunits of the influenza virus polymerase (center) determines whether or not the enzyme works efficiently in birds, pigs or humans. A mutation in the PB2 subunit allows the bird virus to function in humans, as does switching out the bird PA subunit for a human PA subunit. Two mutations in the PB2 subunit of 2009 H1N1 allow the pig virus to work in humans. The background is a false-color electron micrograph image of influenza virions. (Andrew Mehle/UC Berkeley)

In a report in this week’s early online edition of the journal Proceedings of the National Academy of Sciences, University of California, Berkeley, researchers show that the H1N1, or swine flu, virus adopted a new mutation in one of its genes distinct from the mutations found in previous flu viruses, including those responsible for the Spanish influenza pandemic of 1918, the “Asian” flu pandemic in 1957 and the “Hong Kong” pandemic of 1968.

Previous influenza strains that crossed from birds into people had a specific point mutation in the bird virus’s polymerase gene that allowed the protein to operate efficiently inside humans as well. The polymerase transcribes the virus’s RNA, allowing the host to express viral genes, and also copies the viral genome, needed to make new viruses.

The 2009 H1N1 virus retains the bird version of the polymerase, but has a second mutation that seems to suppress the ability of human cells to prevent the bird polymerase from working.

“We were quite shocked when we looked at the swine flu virus, which was clearly replicating in people and other mammalian systems, yet had a polymerase that looked like it was derived from a bird virus, which should not function too well in a human cell type,” said UC Berkeley post-doctoral fellow Andrew Mehle of the Department of Molecular and Cell Biology. “The other mutation within the polymerase seems to compensate and allow the enzyme to function.”

The researchers also discovered another strategy – one not yet adopted by any known flu virus – by which influenza virus can increase its virulence even more. When a particular human subunit is substituted for one of the three protein subunits that make up the bird polymerase, the new combination makes the polymerase more efficient in human cells.

“This is an extremely rare mutation and a rare combination, which suggests that there may be other ways that haven’t emerged yet that these viruses are going to continue to evolve,” said Jennifer Doudna, UC Berkeley professor of molecular and cell biology and an investigator in the Howard Hughes Medical Institute.

“As mechanistic biologists, we are hoping that by understanding how the virus works at the molecular level, we will be able to predict with more accuracy how it will evolve.”

She suggested that those monitoring influenza outbreaks around the world in search of new variants be on the lookout for this recombination of polymerase subunits, which could herald an uptick in swine flu virulence. The findings also could help scientists develop better antiviral treatments, Mehle and Doudna said.

“The more we can understand the biochemistry and the particular structure of these polymerase complexes, the better we can make rational decisions about drug development,” Mehle said.

H1N1, which appeared on the scene earlier this year, was dubbed swine flu because it emerged from pigs, in which human, bird and pig influenza viruses mixed, swapped genes and gave rise to a variant that could infect human cells and reproduce.

While mutations in the surface protein hemagglutinin – indicated by the H in H1N1 – are key to allowing the virus to enter human cells, mutations in the polymerase enzyme are key to the virus’s ability to replicate inside human cells. All previous flu strains that entered and were transmitted in humans had a single mutation in the second subunit of the bird polymerase gene, which apparently allowed the enzyme to operate in human cells.

Last year, Mehle and Doudna showed that human cells apparently prevent the three subunits of bird virus polymerases from assembling into a functioning enzyme. A single amino acid switch at position 627 on the second subunit of the polymerase overcomes that inhibition and allows the virus to replicate. Apparently, Mehle said, when the amino acid glutamic acid – typical of most bird virus polymerases – is changed to a lysine, typical of human polymerases, the surface charge of the subunit changes from acidic (negatively charged) to basic (positively charged) and allows assembly of the subunits. Previous studies in mammals have shown that a lysine in that position enhances polymerase activity, increases viral replication and transmission, and in some cases, is associated with increased pathogenicity and death.

In their new study, Mehle and Doudna found that H1N1 has two rare mutations in the second subunit: a serine at position 590 and an arginine at position 591. This combination, which is most common in pigs, apparently has the same effect on surface charge as the mutation at position 627, allowing the polymerase complex to form and function in human cells.

Mehle noted that, in addition to such point mutations, flu viruses also mix and match the three subunits. Both the 1957 and 1968 viruses had polymerases composed of a first subunit from a bird and the other two subunits from humans. H1N1 has a human-like first subunit, while the second and third are bird-like – hence the need for a mutation in the second subunit to make it more human-like.

To see which other combinations might make H1N1 more virulent, they mixed human, avian and pig subunits in culture, replicating the pig “mixing vessel,” Mehle said. Several combinations with a human third subunit increased the activity of the polymerase enzyme when other mutations were not present in the second subunit. Viruses with this alteration are now being tested in human cell culture to see if they are more virulent.

“In addition to having individual amino acid changes affecting the ability of the virus to transmit across species and be more pathogenic, we need to think about these entire gene segments being exchanged back and forth,” said Doudna, who also is a faculty affiliate of the California Institute for Quantitative Biosciences (QB3). “Those will affect the outcome of disease.”

“We are very hopeful that the kind of basic science that we are doing here will have an impact on human health, either at the level of diagnostics or thinking forward to development of antiviral therapeutics,” she added.

Mehle and Doudna continue to explore the polymerase to discover what in human cells prevents the assembly of the bird polymerase, and to determine the three-dimensional structure of the enzyme and its three subunits.

The work was supported by the National Institute of General Medical Sciences of the National Institutes of Health.

Whether your organization utilizes an agile or waterfall development methodology, the addition of static analysis will bring about a change in the way your development team thinks about their code. This is because an accurate static analysis tool is a source of information that demands the attention of developers, QA testers, and managers alike. Read this white paper to learn best practices for managing statically detected defects, as well as how to set the right static analysis defect reduction goals for you and your team.

Download white paper

Bridging the gap between CAD and GIS, AutoCAD Map 3D allows engineering and GIS professionals to work with the same data, and enables design processes to integrate geospatial functions in a single environment for more efficient workflows.

This results in better designs, increased productivity, and better data quality. View this screencast to learn about the top five ways AutoCAD Map 3D can help you improve your infrastructure design process.

View screencast

Software integrity experts Mark Donsky and George Swan, Ph.D, from Coverity present how static analysis supports Agile to automate testing and find defects earlier in the development cycle, enforces in-cycle QA to share the quality responsibility across QA and development, and is used at Coverity to support its own development processes to deliver high quality, error-free code faster.

View webcast

Hear industry experts discuss using static analysis to identify the top software code issues, how to identify those hard to spot defects that could lead to quality, security and performance issues, how to divide and conquer to fix the defects once identified, and how to prevent defects from occurring as the development cycle moves forward.

View webcast

Gain insight into how to successfully overcome strict compliance and testing requirements, and increasing demand for increasingly complex functionality with Coverity software integrity products for organizations with zero tolerance policies for software failures and security breaches. Results summarized alongside Deloitte, VDC Research, and other studies.

View video in wma format

Hugh Thompson, Chief Security Strategist at People Security and a world-renowned expert in application security, debunks several important software security myths.

In this paper, we outline some of the most prevalent myths about security that you should consider when looking to improve the security of your software. Falling prey to these deadly myths could at best cause you to waste valuable cycles on useless “security” activities or at worst, cause your applications to be less secure.

Download white paper

Data center electrical efficiency is rarely planned or managed. The unfortunate result is that most data centers waste substantial amounts of electricity. Today it is both possible and prudent to plan, measure, and improve data center efficiency. In addition to reducing electrical consumption, efficiency improvements can gain users higher IT power densities and the ability to install more IT equipment in a given installation. This paper explains how data center efficiency can be measured, evaluated, and modeled, including a comparison of the benefits of periodic assessment vs. continuous monitoring.

Download white paper

There is much confusion in the marketplace about the different types of UPS systems and their characteristics. Each of these UPS types is defined, practical applications of each are discussed, and advantages and disadvantages are listed. With this information, an educated decision can be made as to the appropriate UPS topology for a given need.

Download white paper