bluuebunny/crossref_metadata_2025 huggingface dataset:
Health education for Somali Bantu refugees via home visits
Authors: Eisenhauer Elizabeth R. , Mosher Elaine C. , Lamson Karen S. , Wolf Helen Ann , Schwartz Diane G.
Published: February 2012

Background:  Somali Bantu refugees, with unique health information needs, created challenges for health and social service providers.

Objectives:  A service innovation was developed (i) to raise awareness, especially among local health and social service providers, about the Bantu refugees’ presence in the community, their culture, and their information needs and (ii) to deliver needed health information, emphasizing child health, to the Bantu mothers in their homes.

Methods:  The project consisted of: (i) a community conference targeting local health and social service providers, describing the refugees’ presence in the community, their culture, and information needs. (ii) Focus groups conducted with members of the Bantu population elicited additional information needs. (iii) Curriculum was developed based on identified needs, and (iv) the curriculum was delivered to the refugees in their homes. A clinical informationist and MP3 technology enhanced the project.

Findings:  Conference attendees’ evaluation responses indicated improved understanding of Bantu culture. Focus groups’ identification of health information needs provided a framework for the health education curriculum. A project website made educational materials available to other healthcare providers.

Conclusions:  The project raised awareness of the Bantus’ presence, culture, and information needs. Identification of other unmet needs demonstrated that additional support for refugees is required.
Human longevity and common variations in the LMNA gene: a meta‐analysis
Authors: Conneely Karen N. , Capell Brian C. , Erdos Michael R. , Sebastiani Paola , Solovieff Nadia , Swift Amy J. , Baldwin Clinton T. , Budagov Temuri , Barzilai Nir , Atzmon Gil , Puca Annibale A. , Perls Thomas T. , Geesaman Bard J. , Boehnke Michael , Collins Francis S.
Published: February 2012

A mutation in the LMNA gene is responsible for the most dramatic form of premature aging, Hutchinson–Gilford progeria syndrome (HGPS). Several recent studies have suggested that protein products of this gene might have a role in normal physiological cellular senescence. To explore further LMNA’s possible role in normal aging, we genotyped 16 SNPs over a span of 75.4 kb of the LMNA gene on a sample of long‐lived individuals (LLI) (US Caucasians with age ≥ 95 years, N = 873) and genetically matched younger controls (N = 443). We tested all common nonredundant haplotypes (frequency ≥ 0.05) based on subgroups of these 16 SNPs for association with longevity. The most significant haplotype, based on four SNPs, remained significant after adjustment for multiple testing (OR = 1.56, P = 2.5 × 10−5, multiple‐testing‐adjusted P = 0.0045). To attempt to replicate these results, we genotyped 3619 subjects from four independent samples of LLI and control subjects from (i) the New England Centenarian Study (NECS) (N = 738), (ii) the Southern Italian Centenarian Study (SICS) (N = 905), (iii) France (N = 1103), and (iv) the Einstein Ashkenazi Longevity Study (N = 702). We replicated the association with the most significant haplotype from our initial analysis in the NECS sample (OR = 1.60, P = 0.0023), but not in the other three samples (P > 0.15). In a meta‐analysis combining all five samples, the best haplotype remained significantly associated with longevity after adjustment for multiple testing in the initial and follow‐up samples (OR = 1.18, P = 7.5 × 10−4, multiple‐testing‐adjusted P = 0.037). These results suggest that LMNA variants may play a role in human lifespan.
Liposome‐Encapsulated Hemoglobin Improves Energy Metabolism in Skeletal Muscle Ischemia and Reperfusion in the Rat
Authors: Kurita Daisuke , Kawaguchi Akira T. , Aso Kensuke , Yamano Mariko , Minamitani Haruyuki , Haida Munetaka
Published: February 2012

The effect of liposome‐encapsulated hemoglobin (LEH) was tested in a rodent model of limb ischemia and reperfusion—causing local reperfusion injury and a cascade of systemic responses. Intracellular pH (pHi) and phosphocreatine (PCr)/inorganic phosphate (Pi) ratio were serially monitored using 31P‐nuclear magnetic resonance spectroscopy with a 2‐cm solenoid coil on a rodent hind limb. After baseline measurements, the right hind limb underwent ischemia for 70 min, followed 10 min later by intravenous administration of LEH (10 mL/kg, n = 6), homologous red blood cells (RBCs, n = 6), saline (n = 6), or no treatment (n = 6). Reperfusion was then observed for an additional 60 min. While pHi decreased precipitously after the onset of ischemia and even following reperfusion, LEH‐treated rats had significantly milder intracellular acidosis compared with all other groups during ischemia, and after reperfusion as well throughout the observation with the saline‐treated rats. In contrast, the PCr/Pi ratio decreased regardless of treatment after ischemia until reperfusion, when the ratio returned toward normal or the energy status improved only in the LEH‐treated rats, while the ratio remained depressed in the control animals receiving RBC, saline, or no treatment. Morphological studies 7 days later revealed a tendency toward suppressed mononuclear cell infiltration with preservation of muscular mass and structure in the LEH‐treated rats. LEH treatment after early limb ischemia appeared to improve intracellular energy metabolism and eventually preserve skeletal muscle in a rodent model of limb ischemia and reperfusion.
Neural Processes of an Indirect Analog of Risk Taking in Young Nondependent Adult Alcohol Drinkers—An fMRI Study of the Stop Signal Task
Authors: Bednarski Sarah R. , Erdman Emily , Luo Xi , Zhang Sheng , Hu Sien , Li Chiang‐Shan R.
Published: February 2012

Background:  Alcohol abuse and dependence are common problems in the United States that stem from a variety of factors, one of which may be a period of high level social drinking during college and early adulthood. Extant study implicates risk taking as a cognitive factor that contributes to habitual and heavy drinking. We sought to examine the neural processes of risk taking in young, nondependent drinkers.

Methods:  We compared 20 young adult social drinkers with a high level of alcohol use (AH), as defined by number of drinks per month, and 21 demographically matched drinkers with low to moderate alcohol use (ALM) in a functional magnetic resonance imaging study of the stop signal task. By contrasting risk taking (speeded) to risk aversion (slowed) trials, we examined the neural correlates of risk taking. Brain imaging data were analyzed with Statistical Parametric Mapping. Regions of interest were identified and corresponding effect sizes were examined for correlations with self‐reported alcohol use.

Results:  The results showed that, compared with ALM, AH demonstrated decreased activation in right superior frontal gyrus and left caudate nucleus when contrasting risk taking and risk aversion trials at p < 0.001, uncorrected. Furthermore, examination of the effect size data showed that the extent of these decreased regional activations correlated with frequency of drinking in women, but not men.

Conclusions:  These findings suggest a neural analog of nondependent, high level drinking. Specifically, high level social drinking is associated with altered activation of the caudate and superior frontal cortex, an association that appears to be stronger in women than in men and is strongly tied to the frequency of drinking. These results are relevant in understanding risk taking behavior in social drinking as well as in examining the potential path from high level social use in young adults to dangerous alcohol consumption later in life.
Parental Involvement in Neonatal Pain Management: An Empirical and Conceptual Update
Authors: Franck Linda S , Oulton Kate , Bruce Elizabeth
Published: February 2012

Background: New findings are emerging about parental perceptions and desires for involvement in infant pain management in the neonatal intensive care unit (NICU) setting, and the importance of building greater knowledge about this aspect of the patient care is beginning to be appreciated.

Objectives: The study had two aims: (a) to describe perceptions and feelings of parents who participated in a randomized controlled trial of an intervention to increase parent knowledge and involvement in infant pain management; and (b) to further refine the conceptual representation of the parental experience of involvement in infant pain management (or lack thereof) and the influencing factors.

Methods: Thematic analysis was used to explore the content of parents’ written comments and to integrate the present and previous research findings.

Results: Parents expressed strong preferences for more information about all aspects of infant pain care, improved timing of information giving, and involvement opportunities. They further desired increased sensitivity and consistency in infant care giving and increased use of specific pain‐relieving interventions by NICU staff. Contextual factors such as parents’ emotional state and the communication and support from NICU staff influenced parents’ ability to achieve their desired level of involvement.

Discussion: The role of parents in infant pain management is a relatively new area of research. The discussion of conceptual models to guide research and practice is an important milestone representing new opportunity for further scientific developments with important clinical implications for the nursing care of critically ill infants and their families.

Clinical Relevance: New data continue to emerge about parental perceptions and desires for involvement in infant pain management. A new empirically based model may be useful to nurses in providing optimal pain management for NICU infants in partnership with parents.

Journal of Nursing Scholarship, 2011; 44:1, XXX–XXX. ©2011 Sigma Theta Tau International.
Influence of Demographic Factors, Knowledge, and Beliefs on Jordanian Women's Intention to Undergo Mammography Screening
Authors: Othman Areej K. , Kiviniemi Marc T. , Wu Yow‐Wu B. , Lally Robin M.
Published: February 2012

Purpose: The purpose of this study was to determine the influence of demographic characteristics, breast cancer knowledge, fatalistic beliefs, health beliefs, and subjective norms on Jordanian women's intention to participate in mammography screening.

Design: A cross‐sectional survey was used to collect data at 14 comprehensive healthcare centers in Amman and Zarqa, Jordan. A convenience sample of 142 Jordanian women 40 years of age or older with no history of breast cancer and able to read and write in Arabic participated.

Methods: Self‐report surveys included a combination of researcher‐designed and existing instruments to measure the study variables. Data were analyzed using descriptive statistics, Pearson's correlation, t tests, and multiple logistic regression.

Findings: Jordanian women surveyed lacked knowledge about breast cancer. Social norms and self‐efficacy highly influenced these women's intention to engage in mammography screening. Younger women were more willing to indicate intention to engage in mammographic screening.

Conclusions: Self‐efficacy and the social connectedness of Jordanian society, but not religious beliefs or perceived barriers to screening, influence Jordanian women's intention to undergo mammography. Future research should examine cultural influences, rather than religious beliefs, and investigate Jordanian women's potentially unique perspectives on barriers to actual mammography screening behavior.

Clinical Relevance: The prevalence of mammography screening may be enhanced by focusing interventions on Jordanian women's support systems and empowering women by providing knowledge and skills needed to engage in the procedure.

Journal of Nursing Scholarship, 2012; 44:1, XXX–XXX. ©2011 Sigma Theta Tau International.
Settling behavior of the glassy‐winged sharpshooter, Homalodisca vitripennis, vector of Xylella fastidiosa, on southern highbush blueberry cultivars
Authors: Tertuliano M. , Srinivasan R. , Scherm H.
Published: February 2012

The xylem‐limited bacterium Xylella fastidiosa Wells, Raju, Hung, Wiseberg, Mandelico‐Paul & Brenner causes bacterial leaf scorch, a new disease of southern highbush blueberry [Vaccinium corymbosum L. (Ericaceae) interspecific hybrids] in the southeastern USA. The bacterium is transmitted by sharpshooter leafhoppers (Hemiptera: Cicadellidae), with the glassy‐winged sharpshooter (GWSS), Homalodisca vitripennis (Germar), being the most common potential vector in blueberry plantings. Considerable differences are observed in disease intensity among blueberry cultivars in the field, but it remains unknown whether these differences are due to variations in cultivar susceptibility to the bacterium, differences in attractiveness to its vector(s), or both. The settling and feeding behavior of GWSS was evaluated on three southern highbush blueberry cultivars (FL 86‐19, Star, and Emerald) in the greenhouse; in previous field studies, these cultivars were found to be affected by bacterial leaf scorch at high, moderate, and low levels, respectively. Potted plants were caged together with field‐collected GWSS adults for a period of 5 days, with either all three cultivars caged simultaneously (choice test) or individually (no‐choice test). In the choice tests, no differences in cultivar attractiveness were observed during the first 2 days of study. However, from the 3rd day, significantly more adults settled on Emerald (52.7%) than on Star (25.5%) and FL 86‐19 (17.7%). In contrast, in no‐choice tests, the overall host plant acceptance for the three cultivars was similar, and 89.3–92.1% of adults settled on these plants. A significantly greater number of adults settled on the stems (79.3%) vs. the leaves (11.2%). Moreover, they preferred the middle portion of the shoot (56.9%) compared with the upper (7.8%) and the lower (14.7%) portions. In a separate study on FL 86‐19, greater numbers of GWSS nymphs settled on the upper (actively growing) portion of the shoot (82.3%), whereas only 15.8 and 1.5% settled on the middle and lower portions, respectively.
Immediate provisional restoration of single‐piece zirconia implants: a prospective case series – results after 24 months of clinical function
Authors: Payer Michael , Arnetzl Vincent , Kirmeier Robert , Koller Martin , Arnetzl Gerwin , Jakse Norbert
Published: February 2012

Objective

Aim of this prospective case series was to evaluate the outcome of immediately provisionalized single‐piece zirconia implants.

Material and methods

A total of 20 zirconia implants were inserted in single‐tooth gaps in the maxilla (11) and mandible (9) of 20 patients. Implants were restored with all‐ceramic CAD/CAM provisionals without occlusal contacts immediately after placement. Permanent all‐ceramic restoration was performed 4 months after surgery. Plaque index (PI), bleeding on probing (BOP), Periotest® (PV), pink aesthetic score (PES), mean radiographic marginal bone levels (MBL), implant survival and success were evaluated up to 24 months.

Results

Assessment of PI at baseline and follow‐ups after 6, 12, 18 and 24 months revealed 27% (±5.3), 24% (±6), 23% (±6.1), 23% (±5.3) and 22% (±6.4), respectively. Evaluation of BOP revealed 25% (±5.6), 21% (±6), 21% (±7.2), 18% (±5.9) and 15% (±5.5), respectively. Implants presented stable at follow‐ups (PV). PES improved, but not statistically significant from 8.13 (±1.5) at baseline to 10 (±2) 24 months after implantation. Measurements of MBL showed a significant bone loss of 1.01 mm within the first year after placement (P < 0.001) and 1.29 mm 24 months post‐implant insertion, not reaching further statistically significant levels (P > 0.05). One implant was lost 4 months after placement, resulting in a survival and success rate of 95%.

Conclusion

Clinical and radiographic parameters demonstrated a 95% integration of immediately loaded zirconia single‐piece implants. A long‐term randomized‐controlled clinical trial was initiated to confirm evidence of this protocol.
Immunohistochemical dual staining as an adjunct in assessment of mitotic activity in melanoma
Authors: Ikenberg Kristian , Pfaltz Madeleine , Rakozy Christiane , Kempf Werner
Published: February 2012

Background: The mitotic rate was introduced as a major prognostic criterion for the staging of thin (≤1.0 mm) melanoma by the 2009 American Joint Committee on Cancer Staging and Classification (seventh edition). The detection of a single mitotic figure changes the tumor stage in thin melanoma. We sought to address the value of a dual staining to facilitate the determination of the mitotic rate and to assign the mitotic activity to melanocytes.

Methods: The mitotic rate of melanoma cells was determined by dual phosphohistone‐H3 (PHH3)/Melan‐A immunohistochemistry. Results were compared with PHH3 staining alone and conventional hematoxylin and eosin (H&E)‐stained slides of 15 melanomas with a tumor thickness <1.0 mm.

Results: PHH3 staining clearly labeled cells in the mitotic cell cycle. The mitotic rate in the PHH3/Melan‐A dual stain was equal to that derived by H&E staining. Time required for counting mitotic figures was significantly reduced.

Conclusions: The evaluation of mitotic rate with an immunohistochemical dual stain is faster (mean 63.0%) and more reliable than evaluation by routine H&E staining alone. Dual staining immunohistochemistry may be a useful additional tool to standardize the determination of mitotic rate and may be helpful in evaluation of challenging cases.

Ikenberg K, Pfaltz M, Rakozy C, Kempf W. Immunohistochemical dual staining as an adjunct in assessment of mitotic activity in melanoma.
Randomised controlled pilot study in Japan comparing a home visit program using a Functioning Improvement Tool with a home visit with conversation alone
Authors: Ukawa Shigekazu , Yuasa Motoyuki , Ikeno Tamiko , Yoshioka Eiji , Satoh Hiroki , Murata Waka , Ikoma Katsunori , Kishi Reiko
Published: February 2012

Aim:  This study aimed to determine the effect of a home visit program using a Functioning Improvement Tool (FIT) compared with a home visit using conversation alone.

Methods:  Twenty‐eight participants (mean age, 78.6 ± 7.5 years) were randomly assigned to an intervention (n = 13) or control (n = 15) group for 3 months. The intervention group received a 60‐minute FIT home visit program; the control group received a 30‐minute home visit using common conversational techniques. Measures were Mini‐Mental State Examination, Frontal Assessment Battery (FAB) and Geriatric Depression Scale.

Results:  The FAB score was significantly improved in the intervention group compared with the control group (2.5 vs −0.5, P = 0.02).

Conclusions:  Our FIT home visit program improved cognitive function. Further studies with larger samples and longer follow‐up periods are needed to assess the long‐term effectiveness of a FIT home visit program on cognition.
Inhibition of Bacterial Virulence: Drug‐Like Molecules Targeting the Salmonella enterica PhoP Response Regulator
Authors: Tang Yat T. , Gao Rong , Havranek James J. , Groisman Eduardo A. , Stock Ann M. , Marshall Garland R.
Published: February 2012

Two‐component signal transduction (TCST) is the predominant signaling scheme used in bacteria to sense and respond to environmental changes in order to survive and thrive. A typical TCST system consists of a sensor histidine kinase to detect external signals and an effector response regulator to respond to external changes. In the signaling scheme, the histidine kinase phosphorylates and activates the response regulator, which functions as a transcription factor to modulate gene expression. One promising strategy toward antibacterial development is to target TCST regulatory systems, specifically the response regulators to disrupt the expression of genes important for virulence. In Salmonella enterica, the PhoQ/PhoP signal transduction system is used to sense and respond to low magnesium levels and regulates the expression for over 40 genes necessary for growth under these conditions, and more interestingly, genes that are important for virulence. In this study, a hybrid approach coupling computational and experimental methods was applied to identify drug‐like compounds to target the PhoP response regulator. A computational approach of structure‐based virtual screening combined with a series of biochemical and biophysical assays was used to test the predictability of the computational strategy and to characterize the mode of action of the compounds. Eight compounds from virtual screening inhibit the formation of the PhoP‐DNA complex necessary for virulence gene regulation. This investigation served as an initial case study for targeting TCST response regulators to modulate the gene expression of a signal transduction pathway important for bacterial virulence. With the increasing resistance of pathogenic bacteria to current antibiotics, targeting TCST response regulators that control virulence is a viable strategy for the development of antimicrobial therapeutics with novel modes of action.
Final‐year student and employer views of essential personal, interpersonal and professional attributes for new veterinary science graduates
Authors: Schull DN , Morton JM , Coleman GT , Mills PC
Published: February 2012

Objective  To describe the perceptions of final‐year veterinary science students regarding the importance of a variety of personal, interpersonal and professional attributes for new graduates, and to compare these with the views held by employers of new veterinary science graduates.

Design  Final‐year veterinary science students at The University of Queensland and a sample of employers of new graduates from The University of Queensland were surveyed using a written questionnaire.

Results  The distributions of responses given by students and employers did not differ significantly for 44 of 54 attributes listed. Communication skills, teamwork, respect for co‐workers, honesty and an awareness of personal limitations were valued highly by students and employers.

Conclusion  Final‐year students and employers of new graduates from The University of Queensland ascribe similar importance to a variety of personal, interpersonal and professional attributes for new veterinary science graduates.
Gene flow networks among American Aedes aegypti populations
Authors: Gonçalves da Silva Anders , Cunha Ivana C. L. , Santos Walter S. , Luz Sérgio L. B. , Ribolla Paulo E. M. , Abad‐Franch Fernando
Published: February 2012

The mosquito Aedes aegypti, the dengue virus vector, has spread throughout the tropics in historical times. While this suggests man‐mediated dispersal, estimating contemporary connectivity among populations has remained elusive. Here, we use a large mtDNA dataset and a Bayesian coalescent framework to test a set of hypotheses about gene flow among American Ae. aegypti populations. We assessed gene flow patterns at the continental and subregional (Amazon basin) scales. For the Americas, our data favor a stepping‐stone model in which gene flow is higher among adjacent populations but in which, at the same time, North American and southeastern Brazilian populations are directly connected, likely via sea trade. Within Amazonia, the model with highest support suggests extensive gene flow among major cities; Manaus, located at the center of the subregional transport network, emerges as a potentially important connecting hub. Our results suggest substantial connectivity across Ae. aegypti populations in the Americas. As long‐distance active dispersal has not been observed in this species, our data support man‐mediated dispersal as a major determinant of the genetic structure of American Ae. aegypti populations. The inferred topology of interpopulation connectivity can inform network models of Ae. aegypti and dengue spread.
Is spinal manipulation effective for paediatric conditions? An overview of systematic reviews
Authors: Posadzki Paul , Ernst Edzard
Published: February 2012

The aim of this overview was to critically evaluate the evidence of effectiveness for spinal manipulation in any paediatric condition. Four electronic databases were searched from their inception to July 2011 to identify all relevant systematic reviews of spinal manipulation for any paediatric condition. Reviews were defined as systematic if they included explicit and repeatable inclusion and exclusion criteria. Five systematic reviews were included, which covered the following conditions: infant colic (n=2), kinetic imbalance due to suboccipital strain (n=1), nocturnal enuresis (n=1) and otitis media (n=1). None of the systematic reviews generated conclusive evidence to suggest that spinal manipulation is an effective treatment for any paediatric condition. Collectively these data failed to demonstrate that spinal manipulation is a useful therapy for paediatric complaints. The safety of spinal manipulation in paediatrics is also less than clear.
Does auricular acupuncture reduce postoperative pain after gynaecological surgery?
Authors: Liu J
Published: February 2012

Holzer A, Leitger U, Spacer A, Wenzl R, Herkner H, Kettner S.

Auricular acupuncture for postoperative pain after gynaecological surgery: a randomized controlled trail
[sic].

Minerva Anestesiol 2011; 77: 298–304.
Acupuncture for herpes zoster pain
Authors: Larhammar D
Published: February 2012

Ursini T, Tontodonati M, Manzoli L, Polilli E, Rebuzzi C, Congedo G, Di Profio S, Marani Toro P, Consorte A, Placido G, Laganà S, D'Amario C, Granchelli C, Parruti G, Pippa L, VZV Pain Study Group.

Acupuncture for the treatment of severe acute pain in herpes zoster: results of a nested, open‐label, randomized trial in the VZV pain study.

BMC Complement Altern Med 2011; 11: 46.
Efficacy and safety of Antarth for osteoarthritis
Authors: Hung SK
Published: February 2012

Gupta AK, Acharya K, Sancheti PS, Joshi RS.

A double‐blind, randomized, multicentric, placebo‐controlled clinical trial of Antarth, a phytomedicine, in the treatment of osteoarthritis.

Indian J Pharmacol 2011; 43: 69–72.
Liquid Cooling Network Systems for Energy Conservation in Data Centers
Authors: Ouchi Mayumi , Abe Yoshiyuki , Fukagaya Masato , Ohta Haruhiko , Shinmoto Yasuhisa , Sato Masahide , Iimura Ken-ichi
Published: February 2012

Energy consumption in data center has been drastically increasing in recent years. In data center, server racks are cooled down by air conditioning for the whole room in a roundabout way. This air cooling method is inefficient in cooling and it causes hotspot problem that IT equipments are not cooled down enough, but the room is overcooled. On the other hand, countermeasure against the heat of the IT equipments is also one of the big issues. We therefore proposed new liquid cooling systems which IT equipments themselves are cooled down and exhaust heat is not radiated into the server room. For our liquid cooling systems, three kinds of cooling methods have been developed simultaneously. Two of them are direct cooling methods that the cooling jacket is directly attached to heat source, or CPU in this case. Single-phase heat exchanger or two-phase heat exchanger is used as cooling jackets. The other is indirect cooling methods that the heat generated from CPU is transported to the outside of the chassis through flat heat pipes, and condensation sections of the heat pipes are cooled down by liquid. Verification tests have been conducted by use of real server racks equipped with these cooling techniques while pushing ahead with five R&D subjects which constitute our liquid cooling system, which single-phase heat exchanger, two-phase heat exchanger, high performance flat heat pipes, nanofluids technology, and plug-in connector. As a result, the energy saving effect of 50∼60% comparing with conventional air cooling system was provided in direct cooling technique with single-phase heat exchanger.
Precision Evaluation for Thermal Fatigue Life of Power Module Using Coupled Electrical-Thermal-Structural Analysis
Authors: Takahashi Tomohiro , Yu Qiang , Kobayashi Masahiro
Published: February 2012

For power module, the reliability evaluation of thermal fatigue life by power cycling has been prioritized as an important concern. Since in power cycling produces there exists non-uniform temperature distribution in the power module, coupled thermal-structure analysis is required to evaluate thermal fatigue mechanism. The thermal expansion difference between a Si chip and a substrate causes thermal fatigue. In this study, thermal fatigue life of solder joints on power module was evaluated. The finite element method (FEM) was used to evaluate temperature distribution induced by joule heating. Higher temperature appears below the Al wire because the electric current flows through the bonding Al wire. Coupled thermal-structure analysis is also required to evaluate the inelastic strain distribution. The damage of each part of solder joint can be calculated from equivalent inelastic strain range and crack propagation was simulated by deleting damaged elements step by step. The initial cracks were caused below the bonding Al wire and propagated concentrically under power cycling. There is the difference from environmental thermal cycling where the crack initiated at the edge of solder layer. In addition, in order to accurately evaluate the thermal fatigue life, the factors affecting the thermal fatigue life of solder joint where verified using coupled electrical-thermal-structural analysis. Then, the relation between the thermal fatigue life of solder joint and each factor is clarified. The precision evaluation for the thermal fatigue life of power module is improved.
Spatially-Aware Optimization of Energy Consumption in Consolidated Data Center Systems
Authors: Chen Hui , Kesavan Mukil , Schwan Karsten , Gavrilovska Ada , Kumar Pramod , Joshi Yogendra
Published: February 2012

Energy efficiency in data center operation depends on many factors, including power distribution, thermal load and consequent cooling costs, and IT management in terms of how and where IT load is placed and moved under changing request loads. Current methods provided by vendors consolidate IT loads onto the smallest number of machines needed to meet application requirements. This paper’s goal is to gain further improvements in energy efficiency by also making such methods ‘spatially aware’, so that load is placed onto machines in ways that respect the efficiency of both cooling and power usage, across and within racks. To help implement spatially aware load placement, we propose a model-based reinforcement learning method to learn and then predict the thermal distribution of different placements for incoming workloads. The method is trained with actual data captured in a fully instrumented data center facility. Experimental results showing notable differences in total power consumption for representative application loads indicate the utility of a two-level spatially-aware workload management (SpAWM) technique in which (i) load is distributed across racks in ways that recognize differences in cooling efficiencies and (ii) within racks, load is distributed so as to take into account cooling effectiveness due to local air flow. The technique is being implemented using online methods that continuously monitor current power and resource usage within and across racks, sense BladeCenter-level inlet temperatures, understand and manage IT load according to an environment’s thermal map. Specifically, at data center level, monitoring informs SpAWM about power usage and thermal distribution across racks. At rack-level, SpAWM workload distribution is based on power caps provided by maximum inlet temperatures determined by CRAC speeds and supply air temperature. SpAWM can be realized as a set of management methods running in VMWare’s ESXServer virtualization infrastructure. Its use has the potential of attaining up to 32% improvements on the CRAC supply temperature requirement compared to non-spatially aware techniques, which can lower the inlet temperature 2∼3°C, that is to say we can increase the CRAC supply temperature 2∼3°C to save nearly 13% −18% cooling energy.
An Investigation Into Cooling System Control Strategies for Data Center Airflow Containment Architectures
Authors: Patterson Michael K. , Weidmann Rainer , Leberecht Markus , Mair Manuel , Libby Richard M.
Published: February 2012

Data Center efficiency is critical to successful operation of today’s large IT installations. The reduction of infrastructure energy use will allow an increase in IT carrying capacity and / or a reduction in operating costs. The cooling portion of the data center Power Usage Effectiveness (PUE) can represent a significant cost and energy burden to the data center. The use of containment hardware (hot aisle, chimney, or cold aisle containment) is a good step in reducing the Data Center PUE; however the specifics of the implementation remains a challenge and some legacy controls strategies limit the efficacy of their use. The most typical control scheme in today’s data center is the return airflow temperature modulating a linked supply temperature and airflow. This control scheme is unsuitable for an advanced data center and limits the efficiency that can be gained with the containment strategy. But the optimal control scheme for a containment strategy remains a matter of discussion and debate. This paper reports on testing performed at our collaborative data center test lab facility in Munich, Germany where we have explored three different control designs for a containment strategy. The primary goal for energy savings in a containment strategy is to provide just enough cool air to the servers such that the server fans are satisfied without causing any recirculation to occur from the hot side of the containment. We investigated control based on temperature, pressure, and velocity measurements. The specifics of each are discussed as well as recommendations for choosing the appropriate controls. Practical considerations as well as system implementation recommendations are also shared. Each strategy can be made to work but the pressure control scenario provided the best level of control.
Effect of Cyclic Strain-Hardening Exponent on Fatigue Ductility Exponent for Sn Based Alloy
Authors: Kanda Yoshihiko , Oto Yuji , Shiigi Yusuke , Kariya Yoshiharu
Published: February 2012

The influence of cyclic strain-hardening exponents on fatigue ductility exponents for Sn-Bi solid solution alloys and Sn-Ag-Cu microsolder joints was investigated. In Sn-Bi solid solution alloys, the fatigue ductility exponent in Coffin-Manson’s law was confirmed to increase with a decrease in the cyclic strain-hardening exponent. On the other hand, in the Sn-Ag-Cu miniature solder joint, the fatigue ductility exponent increases with a rise in temperature and strain holding. Thus, the fatigue ductility exponents are closely related to the cyclic strain-hardening exponent: the former increases due to the depression of the latter with a rise in temperature and increase in intermetallic compound particle size during strain holding. The results differ for the creep damage mechanism (grain boundary fracture), which is the main reason for the life depression in large-size specimens.
SIF Evaluation Using XFEM and Line Spring Models Under High Strain Rate Environment for Leadfree Alloys
Authors: Lall Pradeep , Kulkarni Mandar , Shantaram Sandeep , Suhling Jeff
Published: February 2012

In this paper, fracture properties of Sn3Ag0.5Cu leadfree high strain-rate solder-copper interface have been evaluated and validated with those from experimental methods. Bi-material Copper-Solder specimen have been tested at strain rates typical of shock and vibration with impact-hammer tensile testing machine. Models for crack initiation and propagation have been developed using Line spring method and extended finite element method (XFEM). Critical stress intensity factor for Sn3Ag0.5Cu solder-copper interface have been extracted from line spring models. Displacements and derivatives of displacements have been measured at crack tip and near interface of bi-material specimen using high speed imaging in conjunction with digital image correlation. Specimens have been tested at strain rates of 20s−1 and 55s−1 and the event is monitored using high speed data acquisition system as well as high speed cameras with frame rates in the neighborhood of 300,000 fps. Previously the authors have applied the technique of XFEM and DIC for predicting failure location and to develop constitutive models in leaded and few leadfree solder alloys [Lall 2010a]. The measured fracture properties have been applied to prediction of failure in ball-grid arrays subjected to high-g shock loading in the neighborhood of 12500g in JEDEC configuration. Prediction of fracture in board assemblies using explicit finite element full-field models of board assemblies under transient-shock is new. Stress intensity factor at Copper pad and bulk solder interface is also evaluated in ball grid array packages.
PHM of Leadfree Interconnects Using Resistance Spectroscopy Based Particle Filter Models for Shock and Vibration Environments
Authors: Lall Pradeep , Lowe Ryan , Goebel Kai
Published: February 2012

Electronic assemblies have been monitored using state-space vectors from resistance spectroscopy, phase-sensitive detection and particle filtering (PF) to quantify damage initiation, progression and remaining useful life of the electronic assembly. A prognostication health management (PHM) methodology has been presented for electronic components subjected to mechanical shock and vibration. The presented methodology is an advancement of the state-of-art, which presently focuses on reactive failure detection and provides limited or no insight into the system reliability and residual life. Previously damage initiation, damage progression, and residual life in the pre-failure space has been correlated with micro-structural damage based proxies, feature vectors based on time, spectral and joint time-frequency characteristics of electronics [Lall2004a-d, 2005a-b, 2006a-f, 2007a-e, 2008a-f]. Precise resistance measurements based on the resistance spectroscopy method have been used to monitor interconnects for damage and prognosticate failure [Lall 2009a,b, 2010a,b, Constable 1992, 2001]. In this paper, the effectiveness of the proposed particle filter and resistance spectroscopy based approach in a prognostic health management (PHM) framework has been demonstrated for electronics. The measured state variable has been related to the underlying damage state using non-linear finite element analysis. The particle filter has been used to estimate the state variable, rate of change of the state variable, acceleration of the state variable and construct a feature vector. The estimated state-space parameters have been used to extrapolate the feature vector into the future and predict the time-to-failure at which the feature vector will cross the failure threshold. Remaining useful life has been calculated based on the evolution of the state space feature vector. Standard prognostic health management metrics were used to quantify the performance of the algorithm against the actual remaining useful life. Application to part replacement decisions for ultra-high reliability system has been demonstrated. Using the technique described in the paper the appropriate time to reorder a replacement part could be monitored, and defended statistically. Robustness of the prognostication algorithm has been quantified using standard performance evaluation metrics.
Nature of Package-Induced Deformation and the Risk of Fracture in Low-k Dielectric Stacks
Authors: Lin Hung-Yun , Tambat Abhishek , Claydon Ian , Subbarayan Ganesh , Jung Dae Young , Sammakia Bahgat
Published: February 2012

The risk of fracture in Interlayer Dielectric (ILD) stack is evaluated for various configurations of flip-chip packages in this paper. A novel analysis on the mechanical behavior of package with a focus on die surface provides the insights into the critical deformation state as well as its location. In Controlled Collapse Chip Connection (C4) process, the reflow phase involves a cooling of the entire package from the reflow temperature to room temperature, and is critical for package induced die cracking (Chip-Package Interaction or CPI). We use commercial finite element software ABAQUS to construct local sub-models of ILD region from global models of a representative 3-D package with component materials modeled as being temperature dependent elastic or elasto-plastic as appropriate. The risk of ILD fracture is systematically investigated using the described approach.
Cloud-Based Scalable Parallel Electromagnetic Tools for Full-System Simulation
Authors: Jandhyala Vikram , Gope Dipanjan , Chakraborty Swagato , Wang Xiren
Published: February 2012

Large-scale public cloud commodity computing is a potential paradigm-shifter for EDA tools. However, to go beyond merely web-hosted software and to exploit the true power of on-demand scalable computing is as yet an unmet challenge on many fronts. In this paper, we examine one computationally expensive and rapidly growing area within EDA as a candidate for the cloud, namely parasitic extraction and electromagnetic field simulation. With the growing emphasis on multifunctional systems in consumer electronics around commodity chips, the need for scale and speed in such tools is paramount. We examine from three aspects the suitability of and modifications needed to accelerated multilevel algorithms in boundary element methods in order to ensure cloud deployment: scalability without hitting Amdahl’s law prematurely, fault tolerance with low time penalties in realistic computing systems, and encryption-free approaches to ensuring IP security.
Supported Iron Nanoparticles as Catalysts for Sustainable Production of Lower Olefins
Authors: Torres Galvis Hirsa M. , Bitter Johannes H. , Khare Chaitanya B. , Ruitenbeek Matthijs , Dugulan A. Iulian , de Jong Krijn P.
Published: February 2012

From Plant to Plastic

Petroleum is primarily used as fuel, but it is also used in the production of plastics. Thus, if biomass were to replace petroleum as society's carbon feedstock, a means of deriving ethylene and propylene—the principal building blocks of today's commodity plastics— would be helpful. Well-known Fischer-Tropsch (FT) catalysts can transform gasified biomass into a range of hydrocarbon derivatives, but ethylene and propylene tend to constitute a small fraction of the overall product distribution.

Torres Galvis
et al.

(p.
835
) now demonstrate a class of iron catalysts on relatively passive supports (carbon nanofibers or α-alumina) that robustly directed the FT process toward light olefins.
A Human Stem Cell Model of Early Alzheimer’s Disease Pathology in Down Syndrome
Authors: Shi Yichen , Kirwan Peter , Smith James , MacLean Glenn , Orkin Stuart H. , Livesey Frederick J.
Published: February 2012

Cultured cerebral cortex neurons generated from human Down syndrome induced pluripotent stem cells rapidly develop Alzheimer’s disease pathologies.
Effect of Increased CRM197Carrier Protein Dose on Meningococcal C Bactericidal Antibody Response
Authors: Lee Lucia H. , Blake Milan S.
Published: February 2012

New multivalent CRM197-based conjugate vaccines are available for childhood immunization. Clinical studies were reviewed to assess meningococcal group C (MenC) antibody responses following MenC-CRM197coadministration with CRM197-based pneumococcal orHaemophilus influenzaetype b conjugate vaccines. Infants receiving a total CRM197carrier protein dose of ∼50 μg and concomitant diphtheria-tetanus-acellular pertussis (DTaP)-containing vaccine tended to have lower MenC geometric mean antibody titers and continued to have low titers after the toddler dose. Nevertheless, at least 95% of children in the reported studies achieved a MenC serum bactericidal antibody (SBA) titer of ≥1:8 after the last infant or toddler dose. SBA was measured using an assay with a baby rabbit or human complement source. Additional studies are needed to assess long-term antibody persistence and MenC CRM197conjugate vaccine immunogenicity using alternative dosing schedules.
Antibodies to Borrelia burgdorferi OspA, OspC, OspF, and C6 Antigens as Markers for Early and Late Infection in Dogs
Authors: Wagner Bettina , Freer Heather , Rollins Alicia , Garcia-Tapia David , Erb Hollis N. , Earnhart Christopher , Marconi Richard , Meeus Patrick
Published: February 2012

Lyme disease in the United States is caused byBorrelia burgdorferisensu stricto, which is transmitted to mammals by infected ticks.Borreliaspirochetes differentially express immunogenic outer surface proteins (Osp). Our aim was to evaluate antibody responses to Osp antigens to aid the diagnosis of early infection and the management of Lyme disease. We analyzed antibody responses during the first 3 months after the experimental infection of dogs using a novel multiplex assay. Results were compared to those obtained with two commercial assays detecting C6 antigen. Multiplex analysis identified antibodies to OspC and C6 as early as 3 weeks postinfection (p.i.) and those to OspF by 5 weeks p.i. Antibodies to C6 and OspF increased throughout the study, while antibodies to OspC peaked between 7 and 11 weeks p.i. and declined thereafter. A short-term antibody response to OspA was observed in 3/8 experimentally infected dogs on day 21 p.i. Quant C6 enzyme-linked immunosorbent assay (ELISA) results matched multiplex results during the first 7 weeks p.i.; however, antibody levels subsequently declined by up to 29%. Immune responses then were analyzed in sera from 125 client-owned dogs and revealed high agreement between antibodies to OspF and C6 as robust markers for infection. Results from canine patient sera supported that OspC is an early infection marker and antibodies to OspC decline over time. The onset and decline of antibody responses toB. burgdorferiOsp antigens and C6 reflect their differential expression during infection. They provide valuable tools to determine the stage of infection, treatment outcomes, and vaccination status in dogs.
Efficient Transmission of Pandemic H1N1 Influenza Viruses with High-Level Oseltamivir Resistance
Authors: Seibert Christopher W. , Rahmat Saad , Krammer Florian , Palese Peter , Bouvier Nicole M.
Published: February 2012

The limited availability of approved influenza virus antivirals highlights the importance of studying the fitness and transmissibility of drug-resistant viruses. S247N is a novel, naturally occurring N1 neuraminidase mutation that reduces oseltamivir sensitivity and greatly potentiates oseltamivir resistance in the context of the H275Y mutation. Here we show that highly oseltamivir-resistant viruses containing both the S247N and H275Y mutations transmit efficiently in the guinea pig transmission model.