Network acceleration techniques

Splintered offloading techniques with receive batch processing are described for network acceleration. Such techniques offload specific functionality to a NIC while maintaining the bulk of the protocol processing in the host operating system ("OS"). The resulting protocol implementation allows the application to bypass the protocol processing of the received data. Such can be accomplished this by moving data from the NIC directly to the application through direct memory access ("DMA") and batch processing the receive headers in the host OS when the host OS is interrupted to perform other work. Batch processing receive headers allows the data path to be separated from the control path. Unlike operating system bypass, however, the operating system still fully manages the network resource and has relevant feedback about traffic and flows. Embodiments of the present disclosure can therefore address the challenges of networks with extreme bandwidth delay products (BWDP)

Genetic Markers Associated with an Intermediate Phenotype of the Metabolic Syndrome: Insulin Resistance and Hypertension

Thesis advisor: Catherine Y. ReadBackground and Significance: The metabolic syndrome is a heterogeneous disorder leading to increased morbidity and mortality. Components of the metabolic syndrome are known to be inherited, however efforts to identify genomic markers in humans have been unsuccessful and a candidate-gene/intermediate phenotype approach may be useful. Evidence supports a relationship between altered metabolic function and three candidate genes, caveolin-1 (CAV1), peroxisome proliferator receptor-activated gamma, and angiotensinogen (AGT). These genes may serve as markers for the co-aggregation of insulin resistance and hypertension. Research Question: To examine whether single nucleotide polymorphisms (SNPs) in the CAV1, PPARg and AGT genes are associated with the co-aggregation of insulin resistance and hypertension. Methods: Three gene association studies were conducted in a Caucasian hypertensive cohort (HyperPATH). The homeostasis assessment model (HOMA-IR), hyperinsulinemic euglycemic clamp, and salt sensitive blood pressure were determined in each subject. Statistical analyses were conducted using a general linear model accounting for relatedness and adjusting for the following covariates: age, gender, body mass index, study site. Replication was assessed in a hypertensive Mexican-American cohort (HTN-IR) for the CAV1 gene and a hypertensive African American cohort (HyperPATH) for the PPARg gene. Results: SNPs of the CAV1 gene were significantly associated with insulin resistance in Caucasians from HyperPATH. These results were replicated in the HTN-IR cohort. A SNP of the PPARg gene was associated with salt sensitive blood pressure and increased plasma renin levels in Caucasians and African Americans from HyperPATH. SNPs of the AGT gene were associated with insulin sensitivity in Caucasians from HyperPATH. Conclusion: CAV1 and AGT are genomic markers for the co-aggregation of insulin resistance and hypertension. The PPARg gene is a potential genomic marker for vascular dysfunction in hypertension. Clinical Perspective: Genomic markers for insulin resistance exist in human populations with hypertension. These markers explain the inter-individual variability of insulin resistance and hypertension and help identify potential underlying mechanisms. Use of these bio-markers in clinical practice may improve individualized prevention and treatment strategies, decreasing the incidence of and improving outcomes for this chronic disease. Promoting health through individualized care makes the incorporation of genomic markers into nursing practice essential.Thesis (PhD) — Boston College, 2010.Submitted to: Boston College. Connell School of Nursing.Discipline: Nursing

Vagal Recovery From Cognitive Challenge Moderates Age-Related Deficits in Executive Functioning

Decline in executive functioning (EF) is a hallmark of cognitive aging. We have previously reported that faster vagal recovery from cognitive challenge is associated with better EF. This study examined the association between vagal recovery from cognitive challenge and age-related differences in EF among 817 participants in the Midlife in the U.S. study (aged 35–86). Cardiac vagal control was measured as high-frequency heart rate variability. Vagal recovery moderated the association between age and EF (β = .811, p = .004). Secondary analyses revealed that older participants (aged 65–86) with faster vagal recovery had superior EF compared to their peers who had slower vagal recovery. In contrast, among younger (aged 35–54) and middle-aged (aged 55–64) participants, vagal recovery was not associated with EF. We conclude that faster vagal recovery from cognitive challenge is associated with reduced deficits in EF among older, but not younger individuals

Long-Term Changes in Physical Activity Following a One-Year Home-Based Physical Activity Counseling Program in Older Adults with Multiple Morbidities

This study assessed the sustained effect of a physical activity (PA) counseling intervention on PA one year after intervention, predictors of sustained PA participation, and three classes of post-intervention PA trajectories (improvers, maintainers, and decliners) in 238 older Veterans. Declines in minutes of PA from 12 to 24 months were observed for both the treatment and control arms of the study. PA at 12 months was the strongest predictor of post-intervention changes in PA. To our surprise, those who took up the intervention and increased PA levels the most, had significant declines in post-intervention PA. Analysis of the three post-intervention PA trajectories demonstrated that the maintenance group actually reflected a group of nonresponders to the intervention who had more comorbidities, lower self-efficacy, and worse physical function than the improvers or decliners. Results suggest that behavioral counseling/support must be ongoing to promote maintenance. Strategies to promote PA appropriately to subgroups of individuals are needed

Weeds in organic fertility-building leys:aspects of species richness and weed management

Legume-based leys (perennial sod crops) are an important component of fertility management in organic rotations in many parts of Europe. Despite their importance, however, relatively little is known about how these leys affect weed communities or how the specific composition of leys may contribute to weed management. To determine whether the choice of plant species in the ley affects weeds, we conducted replicated field trials at six locations in the UK over 24 months, measuring weed cover and biomass in plots sown with monocultures of 12 legume and 4 grass species and in plots sown with a mixture of 10 legume species and 4 grass species. Additionally, we monitored weed communities in leys on 21 organic farms across the UK either sown with a mixture of the project species or the farmers? own species mix. In total, 63 weed species were found on the farms, with the annuals Stellaria media, Sonchus arvensis, and Veronica persica being the most frequent species in the first year after establishment of the ley, while Stellaria media and the two perennials Ranunculus repens and Taraxacum officinale dominated the weed spectrum in the second year. Our study shows that organic leys constitute an important element of farm biodiversity. In both replicated and on-farm trials, weed cover and species richness were significantly lower in the second than in the first year, owing to lower presence of annual weeds in year two. In monocultures, meadow pea (Lathyrus pratensis) was a poor competitor against weeds, and a significant increase in the proportion of weed biomass was observed over time, due to poor recovery of meadow pea after mowing. For red clover (Trifolium pratense), we observed the lowest proportion of weed biomass in total biomass among the tested legume species. Crop biomass and weed biomass were negatively correlated across species. Residuals from the linear regression between crop biomass and weed biomass indicated that at similar levels of crop biomass, grasses had lower weed levels than legumes. We conclude that choice of crop species is an important tool for weed management in leys.authorsversionPeer reviewe

Conducting polymer 3D microelectrodes

Conducting polymer 3D microelectrodes have been fabricated for possible future neurological applications. A combination of micro-fabrication techniques and chemical polymerization methods has been used to create pillar electrodes in polyaniline and polypyrrole. The thin polymer films obtained showed uniformity and good adhesion to both horizontal and vertical surfaces. Electrodes in combination with metal/conducting polymer materials have been characterized by cyclic voltammetry and the presence of the conducting polymer film has shown to increase the electrochemical activity when compared with electrodes coated with only metal. An electrochemical characterization of gold/polypyrrole electrodes showed exceptional electrochemical behavior and activity. PC12 cells were finally cultured on the investigated materials as a preliminary biocompatibility assessment. These results show that the described electrodes are possibly suitable for future in-vitro neurological measurements