bluuebunny/crossref_metadata_2025 huggingface dataset:
Prophylactic dietary restriction may promote functional recovery and increase lifespan after spinal cord injury
Authors: Plunet Ward T. , Lam Clarrie K. , Lee Jae H. T. , Liu Jie , Tetzlaff Wolfram
Published: June 2010

Functional recovery after spinal cord injury (SCI) is limited, and the injury results in a dramatic reduction in long‐term lifespan. Prophylactic dietary restriction (DR) robustly extends animal lifespan, and is beneficial in models of neuronal insult. In rats, we found that one form of DR, every‐other‐day‐fasting (EODF), which started 1 month prior to a cervical SCI improved functional recovery, resulted in greater numbers of neurons surrounding the injury site, and a ∼ 45% reduction in lesion size compared to the control group. In the light of the low‐risk implementation of prophylactic EODF, the clinical translation as a treatment prior to elective subacute or chronic interventions is attractive. There are numerous secondary complications after human SCI, including a 13‐ to 25‐year reduction in lifespan. DR consistently increases median and maximal lifespan in a large range of organisms, including non‐human primates. Animal research suggests that EODF might reduce many of the secondary complications people with SCI suffer from. Dietary interventions may provide the possibility to improve the quality and span of life for individuals with SCI.
Anti‐Nogo on the go: from animal models to a clinical trial
Authors: Zörner Björn , Schwab Martin E.
Published: June 2010

Small lesions of the adult central nervous system (CNS) often have a good prognosis with extensive functional recovery based in part on spontaneous neuritic sprouting and rearrangements of projections. This is well documented for the cortex, but these changes can also occur in the spinal cord. Nogo‐A is a protein present in CNS myelin that inhibits neurite growth. Models of spinal cord injury (SCI) in rats and macaque monkeys demonstrate that treatment with function‐blocking antibodies of Nogo‐A results in an upregulation of growth‐specific proteins, enhanced regenerative and compensatory sprouting of fibers, and the formation of new functional connections in the spinal cord. In animals with unilateral sensorimotor cortex lesions followed by Nogo‐A antibody treatment, fibers from the intact corticofugal system crossed the midline, supplying innervation to the denervated brain stem or spinal cord. Behavioral tests showed marked improvements of functional recovery in the Nogo‐A antibody treated spinal cord‐ or brain‐injured animals. A Phase I clinical trial applying anti‐Nogo‐A antibody to subjects with acute SCI has been successfully conducted and a multicentric, multinational Phase II trial is currently in preparation.
Raised Plasma Urotensin II in Type 2 Diabetes Patients Is Associated With the Metabolic Syndrome Phenotype
Authors: Gruson Damien , Rousseau Michel F. , Ketelslegers Jean‐Marie , Hermans Michel P.
Published: June 2010

J Clin Hypertens(Greenwich). 2010;12:653–660. © 2010 Wiley Periodicals, Inc.

Urotensin II (UII) exerts multiple effects on the cardiovascular system, acts as a diabetogenic agent, and may also contribute to the development of the metabolic syndrome (MetS). The aim of this study was to determine circulating UII in patients with type 2 diabetes mellitus (T2DM) and its relationship with MetS. A total of 360 consecutive patients with T2DM were included. MetS presence/absence (MetS [+]/[−]) was defined according to American Heart Association/National Heart, Lung and Blood Institute criteria. Plasma concentrations of UII were determined by radioimmunoassay. UII levels were significantly higher in MetS (+) than in MetS (−) T2DM patients (0.97 pg/mL [0.93–1.01], n=294 vs 0.82 pg/mL [0.75–0.88] pg/mL, n=66, respectively; P<.001). Multiple logistic regression analysis showed that UII was significantly associated with MetS (+) (odds ratio, 6.41 [95% confidence interval, 1.21–16.04]; P=.02). UII plasma concentrations are significantly higher in T2DM patients presenting with MetS. Therefore, circulating UII may participate in the worsening course of some T2DM patients and may provide novel therapeutic perspectives.
Tracking Cholera in Coastal Regions Using Satellite Observations1
Authors: Jutla Antarpreet S. , Akanda Ali S. , Islam Shafiqul
Published: June 2010

Jutla, Antarpreet S., Ali S. Akanda, and Shafiqul Islam, 2010. Tracking Cholera in Coastal Regions Using Satellite Observations. Journal of the American Water Resources Association (JAWRA) 46(4): 651‐662. DOI: 10.1111/j.1752‐1688.2010.00448.x

Abstract:  Cholera remains a significant health threat across the globe. The pattern and magnitude of the seven global pandemics suggest that cholera outbreaks primarily originate in coastal regions and then spread inland through secondary means. Cholera bacteria show strong association with plankton abundance in coastal ecosystems. This review study investigates the relationship(s) between cholera incidence and coastal processes and explores utility of using remote sensing data to track coastal plankton blooms, using chlorophyll as a surrogate variable for plankton abundance, and subsequent cholera outbreaks. Most studies over the last several decades have primarily focused on the microbiological and epidemiological understanding of cholera outbreaks. Accurate identification and mechanistic understanding of large scale climatic, geophysical, and oceanic processes governing cholera‐chlorophyll relationship is important for developing cholera prediction models. Development of a holistic understanding of these processes requires long and reliable chlorophyll datasets, which are beginning to be available through satellites. We have presented a schematic pathway and a modeling framework that relate cholera with various hydroclimatic and oceanic variables for understanding disease dynamics using the latest advances in remote sensing. Satellite data, with its unprecedented spatial and temporal coverage, have potentials to monitor coastal processes and track cholera outbreaks in endemic regions.
Conclusion to the Featured Series on Satellites and Transboundary Water: Emerging Ideas1
Authors: Hossain Faisal
Published: June 2010

Hossain, Faisal, 2010. Conclusion to the Featured Series on Satellites and Transboundary Water: Emerging Ideas. Journal of the American Water Resources Association (JAWRA) 46(4): 663‐664. DOI: 10.1111/j.1752‐1688.2010.00449.x
REVIEW: Cardiovascular Implantable Electronic Devices in Athletes
Authors: Do Rose , Patton Kristen K.
Published: June 2010

Cardiovascular implantable electronic device (CIED) implantation indications have greatly increased over the past decade, with use of pacemakers and implantable cardiac defibrillators now growing more common even in athletes. Management of CIEDs in this subgroup is of greater complexity due to augmented physical stressors, a longer exposure time to system components in a younger population, and less common, highly clinically variable underlying cardiac pathologies. We will review management issues specific to CIED therapy, sudden cardiac death, and consensus recommendations for physical activity.
Chronotropic Incompentence and Functional Capacity in Chronic Heart Failure: No Role of β‐Blockers and β‐Blocker Dose
Authors: Magrì Damiano , Palermo Pietro , Cauti Filippo M. , Contini Mauro , Farina Stefania , Cattadori Gaia , Apostolo Anna , Salvioni Elisabetta , Magini Alessandra , Vignati Carlo , Alimento Marina , Sciomer Susanna , Bussotti Maurizio , Agostoni Piergiuseppe
Published: June 2010

Aim: To assess the effect of chronotropic incompetence on functional capacity in chronic heart failure (CHF) patients, as evaluated as NYHA and peak oxygen consumption (pVO2), focusing on the presence and dose of β‐blocker treatment. Methods: Nine hundred and sixty‐seven consecutive CHF patients were evaluated, 328 of whom were discarded because they failed to meet the study criteria. Of the 639 analyzed, 90 were not treated with β‐blockers whereas the other 549 were. The latter were further subdivided in high (n = 184) and low (n = 365) β‐blockers daily dose group in accordance with an arbitrary cut‐off of 25 mg for carvedilol and of 5 mg for bisoprolol. Failure to achieve 80% of the percentage of maximum age predicted peak heart rate (%Max PHR) or of HR reserve (%HRR) constituted chronotropic incompetence. Results: No differences were found in NYHA or pVO2 between patients with and without β‐blockers and, similarly, between high and low β‐blocker dose groups. Twenty and sixty‐nine percent of not β‐blocked patients showed chronotropic incompetence according to %Max PHR and %HRR, respectively, whereas this prevalence rose to 61% and 84% in those on β‐blocker therapy. Patients taking β‐blockers without chronotropic incompetence, as inferable from both %Max PHR and %HRR, showed higher NYHA and pVO2 regardless of drug dose, whereas, in not β‐blocked patients, only %HRR revealed a difference in functional capacity. At multivariable analysis, HR increase during exercise (ΔHR) was the variable most strongly associated to pVO2 (β: 0.572; SE: 0.008; P < 0.0001) and NYHA class (β: −0.499; SE: 0.001; P < 0.0001). Conclusions: ΔHR is a powerful predictor of CHF severity regardless of the presence of β‐blocker therapy and of β‐blocker daily dose.
Vitamin D and Cardiovascular Prevention
Authors: Nadir M. Adnan , Szwejkowski Benjamin R. , Witham Miles D.
Published: June 2010

Vitamin D has been known to medical science for almost a century. Yet, it is only in the last 15 years that we have realized that the biological effects of vitamin D extend far beyond the control of calcium metabolism. Recent observational evidence suggests strong links between low vitamin D levels and a range of cardiovascular conditions, including stroke, myocardial infarction, hypertension, and diabetes. Interventional studies are beginning to explore whether vitamin D supplementation can modify vascular health and prevent cardiovascular disease. This article reviews the physiology and function of vitamin D, examines the current observational and intervention data in cardiovascular disease, and discusses future research and current practice recommendations.
REVIEW: Genome‐Wide Findings in Schizophrenia and the Role of Gene–Environment Interplay
Authors: Van Winkel Ruud , Esquivel Gabriel , Kenis Gunter , Wichers Marieke , Collip Dina , Peerbooms Odette , Rutten Bart , Myin‐Germeys Inez , Van Os Jim
Published: June 2010

The recent advent of genome‐wide mass‐marker technology has resulted in renewed optimism to unravel the genetic architecture of psychotic disorders. Genome‐wide association studies have identified a number of common polymorphisms robustly associated with schizophrenia, in ZNF804A, transcription factor 4, major histocompatibility complex, and neurogranin. In addition, copy number variants (CNVs) in 1q21.1, 2p16.3, 15q11.2, 15q13.3, 16p11.2, and 22q11.2 were convincingly implicated in schizophrenia risk. Furthermore, these studies have suggested considerable genetic overlap with bipolar disorder (particularly for common polymorphisms) and neurodevelopmental disorders such as autism (particularly for CNVs). The influence of these risk variants on relevant intermediate phenotypes needs further study. In addition, there is a need for etiological models of psychosis integrating genetic risk with environmental factors associated with the disorder, focusing specifically on environmental impact on gene expression (epigenetics) and convergence of genes and environment on common biological pathways bringing about larger effects than those of genes or environment in isolation (gene–environment interaction). Collaborative efforts that bring together expertise in statistics, genetics, epidemiology, experimental psychiatry, brain imaging, and clinical psychiatry will be required to succeed in this challenging task.
Antidepressant‐Induced Suicidality: An Update
Authors: Reeves Roy R. , Ladner Mark E.
Published: June 2010

Evidence suggests that antidepressant treatment may in some cases result in worsening depression and increased risk of suicidality in pediatric and adolescent patients. The United States Food and Drug Administration requires that antidepressants carry a black box warning regarding such a risk in patients up to age 24. Many studies of antidepressant‐induced suicidality among adults have also reported an increased risk, while several other investigations involving that population have not supported such a finding. This article provides an update of the controversy surrounding antidepressants as a potential cause of suicidal ideations or behavior. Antidepressant‐induced suicidality appears to be an uncommon occurrence but also a legitimate phenomenon. Close monitoring and a follow‐up care should be provided for patients after initiation of a new antidepressant.
The Role of Inflammation in the Pathogenesis of Delirium and Dementia in Older Adults: A Review
Authors: Simone Mark J. , Tan Zaldy S.
Published: June 2010

Aims: To review recent evidence that suggests inflammation plays a similar role in the pathogenesis of delirium and dementia. Methods: We performed a literature search of original research and review articles in PubMed using the keywords: delirium, dementia, and inflammation. We summarized the evidence linking inflammation to the pathogenesis of delirium and dementia. Discussion: Delirium and dementia share similarities in clinical and pathogenic features, leading to the speculation that instead of being distinct clinical entities, the two age‐related conditions may be linked by a common pathogenic mechanism. Inflammatory markers have been shown to be elevated in both delirium and dementia, thereby implicating inflammation as a possible mediating factor in their genesis. There is evidence in both basic science and clinical research literature that elevated cytokines play a crucial role in the development of cognitive dysfunction observed in both dementia and delirium. Conclusion: Mounting evidence supports the role of inflammation in the development of both dementia and delirium. Further studies are needed to elucidate the mechanisms underlying these relationships.
Dynamics of Japanese and Chinese Security Policies in East Asia and Implications for Regional Stability
Authors: Atanassova‐Cornelis Elena , Mendes Carmen Amado
Published: June 2010

This article examines the dynamics of Japanese and Chinese post–Cold War security policies in East Asia and assesses the implications for regional stability. To this end, the discussion explores elements in both countries' security policy behavior, and Sino‐Japanese relations that have a stabilizing and/or destabilizing impact on the region. The article argues that, on the whole, Japanese and Chinese security policies have contributed to more stability than instability. Although the security dilemma between Japan (and the United States) and China may have become more pronounced, the balance of power currently maintained may be assessed in positive terms for the region. In addition, Sino‐Japanese competition for influence has led to strengthening East Asian institution building and thereby fostered stability. While there is ground for cautious optimism regarding the future of Sino‐Japanese cooperation, mutual strategic distrust between Tokyo and Beijing will underpin the security dilemma and their competitive policies in the region.
Exploring the Sources of Institutional Trust in China: Culture, Mobilization, or Performance?
Authors: Yang Qing , Tang Wenfang
Published: June 2010

While democratic countries have been concerned about a “trust crisis” since the 1960s, China surprisingly displays a very high level of public trust in institutions. Why do people trust institutions and to what extent does institutional trust in China differ from that in democracies? Using the 2004 China Values and Ethics Survey, this article explores three different dimensions of institutional trust in China: trust in administrative institutions, trust in legal institutions, and trust in societal institutions. The analysis shows that institutional trust is more than a product of traditional values in China. Rather, it is more of an individual rational choice based heavily on the evaluations of the institutional performance, and it is also a result of government‐controlled politicization. Trust in administrative institutions, in particular, mainly comes from satisfactory institutional performance. Institutional trust has a great impact on the development of democracy and legal participation in China.
The Clash of David and Goliath at Sea: The USSColeBombing as Sea Insurgency and Lessons for the ROK Navy
Authors: Ban Kil‐Joo
Published: June 2010

On October 12, 2000, the USSColewas attacked by a small band of Islamic (global) insurgents. Why would sea insurgents attack a professional warship that did not appear to be related to counterinsurgency? When are such attacks successful, and when are they not successful? Three dimensions—value, vulnerability, and learning—give convincing answers to this puzzle. I trace two cases: the USSColebombing and the USSAshlandandKearsargemissile attack. I find that when the navy is equipped with a fast learning process and this reduces its vulnerability, sea insurgents' attacks are less successful. This strategic interaction dynamic is strongly applicable to South Korea under three subdynamics: alliance, commitment dilemma, and enhanced naval capabilities. Thus, the Republic of Korea Navy needs to establish a flexible strategy in its effort to effectively deal with nontraditional threats as well as traditional threats, such as North Korea.
Thermal Conductance of a Multilayer Drift Chamber: An Experimental Approach
Authors: Daniel-Leal Manuel , Romero-Barajas Luciano , Perez-Diaz Jose L.
Published: June 2010

Drift chambers in the compact muon solenoid (CMS) detector are piled modular structures joined together by a structural adhesive. This structure is used for the detection and tracking of high energy particles—particularly muons. According to Fourier’s law, the conductance of a multilayered drift chamber prototype can be measured using a simple device based on the thermal transience between two heat sinks. The heat gradients in the global CMS detector in operation at the European Council for Nuclear Research are estimated in this way. The resultant values are used to determine whether to include a forced cooling device in the CMS.
Dynamic Modeling of a Novel Cooling, Heat, Power, and Water Microturbine Combined Cycle
Authors: Ryu ChoonJae , Tiffany David R. , Crittenden John F. , Lear William E. , Sherif S. A.
Published: June 2010

The power, water extraction, and refrigeration (PoWER) engine has been investigated for several years as a distributed energy (DE) system among other applications for civilian or military use. Previous literature describing its modeling and experimental demonstration have indicated several benefits, especially when the underlying semiclosed cycle gas turbine is combined with a vapor absorption refrigeration system, the PoWER system described herein. The benefits include increased efficiency, high part-power efficiency, small lapse rate, compactness, low emissions, lower air and exhaust flows (which decrease filtration and duct size), and condensation of fresh water. The present paper describes the preliminary design and its modeling of a modified version of this system as applied to DE, especially useful in regions, which are prone to major grid interruptions due to hurricanes, undercapacity, or terrorism. In such cases, the DE system should support most or all services within an isolated service island, including ice production, so that the influence of the power outage is contained in magnitude and scope. The paper describes the rather straightforward system modifications necessary for ice production. However, the primary focus of the paper is on dynamic modeling of the ice making capacity to achieve significant load-leveling via thermal energy storage during the summer utility peak, hence reducing the electrical capacity requirements for the grid.
Energy and Exergy Analysis of Gasifier-Based Coal-to-Fuel Systems
Authors: Zhu Yunhua , Somasundaram Sriram , Kemp James W.
Published: June 2010

National energy security concerns related to liquid transportation fuels have revived interests in alternative liquid fuel sources. Coal-to-fuel technologies feature high efficiency energy conversion and environmental advantages. While a number of factors are driving coal-to-fuel projects forward, there are several barriers to wide commercialization of these technologies such as financial, construction, operation, and technical risks. The purpose of this study is to investigate the performance features of coal-to-fuel systems based on different gasification technologies. The target products are the Fischer–Tropsch synthetic crude and synthetic natural gas. Two types of entrained-flow gasifier-based coal-to-fuel systems are simulated and their performance features are discussed. One is a single-stage water quench cooling entrained-flow gasifier, and another one is a two-stage syngas cooling entrained-flow gasifier. The conservation of energy (first law of thermodynamics) and the quality of energy (second law of thermodynamics) for the systems are both investigated. The results of exergy analysis provide insights about the potential targets for technology improvement. The features of different gasifier-based coal-to-fuel systems are discussed. The results provide information about the research and development priorities in future.
Turning CO2 Capture On and Off in Response to Electric Grid Demand: A Baseline Analysis of Emissions and Economics
Authors: Cohen Stuart M. , Rochelle Gary T. , Webber Michael E.
Published: June 2010

Coal consumption accounted for 36% of America’s CO2 emissions in 2005, yet because coal is a relatively inexpensive, widely available, and politically secure fuel, its use is projected to grow in the coming decades (USEIA, 2007, “World Carbon Dioxide Emissions From the Use of Fossil Fuels,” International Energy Annual 2005, http://www.eia.doe.gov/emeu/iea/carbon.html). In order for coal to contribute to the U.S. energy mix without detriment to an environmentally acceptable future, implementation of carbon capture and sequestration (CCS) technology is critical. Techno-economic studies establish the large expense of CCS due to substantial energy requirements and capital costs. However, such analyses typically ignore operating dynamics in response to diurnal and seasonal variations in electricity demand and pricing, and they assume that CO2 capture systems operate continuously at high CO2 removal and permanently consume a large portion of gross plant generation capacity. In contrast, this study uses an electric grid-level dynamic framework to consider the possibility of turning CO2 capture systems off during peak electricity demands to regain generation capacity lost to CO2 capture energy requirements. This practice eliminates the need to build additional generation capacity to make up for CO2 capture energy requirements, and it might allow plant operators to benefit from selling more electricity during high price time periods. Post-combustion CO2 absorption and stripping is a leading capture technology that, unlike many other capture methods, is particularly suited for flexible or on/off operation. This study presents a case study on the Electric Reliability Council of Texas (ERCOT) electric grid that estimates CO2 capture utilization, system-level costs, and CO2 emissions associated with different strategies of using on/off CO2 capture on all coal-fired plants in the ERCOT grid in order to satisfy peak electricity demand. It compares base cases of no CO2 capture and “always on” capture with scenarios where capture is turned off during: (1) peak demand hours every day of the year, (2) the entire season of peak system demand, and (3) system peak demand hours only on seasonal peak demand days. By eliminating the need for new capacity to replace output lost to CO2 capture energy requirements, flexible CO2 capture could save billions of dollars in capital costs. Since capture systems remain on for most of the year, flexible capture still achieves substantial CO2 emissions reductions.
Evolution of the Transition to a World Driven by Renewable Energy
Authors: Fronk Brian M. , Neal Richard , Garimella Srinivas
Published: June 2010

The world’s energy supplies will continue to be pressured as the population grows and the standard of living rises in the developing world. A move by the rest of the world toward energy consumption rates on par with the United States is most probably unsustainable. An examination of population trends, current energy utilization rates, and estimated reserves shows that a major worldwide transition to renewable resources is necessary in the next 100 years. This paper examines one possible scenario of how energy usage and renewable power generation must evolve during this time period. As the global standard of living increases, energy consumption in developing nations will begin to approach that of the developed world. A combination of energy conservation and efficiency improvements in developed nations will be needed to push the worldwide energy consumption to approximately 200 million Btu per person per year. Fossil fuel resources will be exhausted or become prohibitively expensive, necessitating the development of renewable energy resources. At this projected steady state population and energy consumption, the required contribution of each type of renewable resource can be calculated. Comparing these numbers to the current renewable capacities illustrates the enormous effort that must be made in the next century.
Life Cycle Assessment of Hydrogen Production Using Nuclear Energy: An Application Based on Thermochemical Water Splitting
Authors: Lubis L. L. , Dincer I. , Rosen M. A.
Published: June 2010

A life cycle assessment of nuclear-based hydrogen production using thermochemical water splitting is conducted. The copper-chlorine thermochemical cycle is considered, and the environmental impacts of the nuclear and thermochemical plants are assessed. Environmental impacts are investigated using CML-2001 impact categories. The nuclear plant and the construction of the hydrogen plant contribute significantly to the total environmental impacts. The environmental impacts of operating the hydrogen production plant contribute much less. Changes in the inventory of materials or chemicals needed in the thermochemical plant do not affect significantly the total impacts. Improvement analysis suggests the development of more sustainable processes, particularly in the nuclear plant and construction of the hydrogen production plant.
Constitutive Modeling and Rupture Predictions of Al-6061-T6 Tubes Under Biaxial Loading Paths
Authors: Korkolis Y. P. , Kyriakides S. , Giagmouris T. , Lee L.-H.
Published: June 2010

This brief note reports the results of a set of biaxial experiments on Al-6061-T6 tubes tested to rupture under radial stress paths of combined internal pressure and axial load. The experiments are then simulated with shell-type finite element models, in which several yield functions are calibrated and implemented and their performance evaluated against the experimental results.
Metacenter and ship stability
Authors: Mégel Jacques , Kliava Janis
Published: June 2010

We address the location of the metacenter M of a floating body such as a ship. Previous studies of M in relation to the stability of a ship have mainly used geometrical approaches and were limited to near equilibrium. We develop a quantitative approach to the location of M for a general shape of the cross-section of a floating body in a rolling/pitching motion and for an arbitrary heel angle. We show that different definitions of M refer to one and the same special point of the floating body. We discuss the relation between the height of M with respect to the line of flotation and the contribution of the buoyancy force to ship stability. We provide expressions and graphs of the buoyancy, flotation, and metacentric curves for some simple shapes of floating bodies.
Rowing and the same-sum problem have their moments
Authors: Barrow John D.
Published: June 2010

We consider the optimal positioning of an even number of identical crew members in a coxless racing boat so as to avoid the presence of a sideways wiggle as the boat is propelled forward through the water. We show that the traditional (alternate port and starboard) positioning always possesses an oscillating nonzero transverse moment and associated wiggling motion and that the problem of finding the zero-moment positions is related to a special case of the subset sum problem. We find the one (known) zero-moment rig for a racing Four and show that there are four possible such rigs for a racing Eight, of which only two are known. We show that only balanced boats with crew numbers that are divisible by four can have the zero-moment property and give the 29 zero-moment solutions for racing Twelves, which have zero transverse moments. Some aspects of unbalanced boats in which the numbers of port and starboard oars are unequal are also discussed.
Helping students learn effective problem solving strategies by reflecting with peers
Authors: Mason Andrew , Singh Chandralekha
Published: June 2010

We study how introductory physics students engage in reflection with peers about problem solving. The recitations for an introductory physics course with 200 students were broken into a “peer reflection” (PR) group and a traditional group. Each week in recitation, small teams of students in the PR group reflected on selected problems from the homework and discussed why the solutions of some students employed better problem solving strategies than others. The graduate and undergraduate teaching assistants in the PR recitations provided guidance and coaching to help students learn effective problem solving heuristics. In the traditional group recitations students could ask the graduate TA questions about the homework before they took a weekly quiz. The traditional group recitation quiz questions were similar to the homework questions selected for peer reflection in the PR group recitations. As one measure of the impact of this intervention, we investigated how likely students were to draw diagrams to help with problem solving on the final exam with only multiple-choice questions. We found that the PR group drew diagrams on more problems than the traditional group even when there was no explicit reward for doing so. Also, students who drew more diagrams for the multiple-choice questions outperformed those who did not, regardless of which group they were a member.
The domino effect
Authors: van Leeuwen J. M. J.
Published: June 2010

The physics of a row of toppling dominoes is discussed. The forces between the falling dominoes are analyzed, including the effect of friction. The propagation speed of the domino effect is calculated for the range of spatial separations for which the domino effect exists. The dependence of the speed as a function of the domino width, height, and interspacing is derived.
High performance Raman spectroscopy with simple optical components
Authors: Somerville W. R. C. , Le Ru E. C. , Northcote P. T. , Etchegoin P. G.
Published: June 2010

Several simple experimental setups for the observation of Raman scattering in liquids and gases are described. Typically these setups do not involve more than a small (portable) CCD-based spectrometer (without scanning), two lenses, and a portable laser. A few extensions include an inexpensive beam-splitter and a color filter. We avoid the use of notch filters in all of the setups. These systems represent some of the simplest but state-of-the-art Raman spectrometers for teaching/demonstration purposes and produce high quality data in a variety of situations; some of them traditionally considered challenging (for example, the simultaneous detection of Stokes/anti-Stokes spectra or Raman scattering from gases). We show examples of data obtained with these setups and highlight their value for understanding Raman spectroscopy. We also provide an intuitive and nonmathematical introduction to Raman spectroscopy to motivate the experimental findings.
Using XBee transducers for wireless data collection
Authors: Ayars Eric , Lai Estella
Published: June 2010

This article describes how to use XBee transducers to create small and lightweight wireless sensors, which send data to a base station for collection and analysis. Data collection is limited to 10-bit accuracy by the XBee hardware. Depending on the type of XBee used, up to six data channels can be transmitted over a range of up to 15 miles. We describe the technical details of the process using the low-power version of the XBee transducer and a three-axis accelerometer chip.
Capture of the Sun's Oort Cloud from Stars in Its Birth Cluster
Authors: Levison Harold F. , Duncan Martin J. , Brasser Ramon , Kaufmann David E.
Published: June 2010

Out of the Oort Cloud

Long-period comets originate from the Oort cloud, a vast reservoir of icy bodies that surrounds the solar system. These bodies are thought to be remnants from the formation of the solar system. But did they all form in the Sun's protoplanetary disk, or could they have been generated in the protoplanetary disks of other stars in the cluster where the Sun probably formed?

Levison
et al.

(p.
187
, published online 10 June) used detailed numerical simulations to investigate what fraction of comets might transfer from the outer reaches of one stellar system to another. The simulations suggest that a substantial number of comets can be captured through this mechanism, which may explain why the number of bodies in the Oort cloud is larger than models predict.
Reprogramming of T Cells to Natural Killer–Like Cells upon
Bcl11b
Deletion
Authors: Li Peng , Burke Shannon , Wang Juexuan , Chen Xiongfeng , Ortiz Mariaestela , Lee Song-Choon , Lu Dong , Campos Lia , Goulding David , Ng Bee Ling , Dougan Gordon , Huntly Brian , Gottgens Bertie , Jenkins Nancy A. , Copeland Neal G. , Colucci Francesco , Liu Pentao
Published: June 2010

One Two T

T cells develop in the thymus, where they proceed through several developmental stages, losing alternative lineage potential as they progress. The molecular regulation of this developmental process, however, is not fully understood (see the Perspective by

Di Santo

).

P. Li
et al.

(p.
85
, published online 10 June),

L. Li
et al.

(p.
89
), and

Ikawa
et al.

(p.
93
) now identify expression of the zinc finger transcription factor
Bcl11b
as the earliest checkpoint in T cell development in mice. Genetic deletion of
Bcl11b
in developing T cells inhibited commitment to the T cell lineage. Under conditions that should have stimulated T lineage differentiation,
Bcl11b
-deficient T cell progenitors failed to up-regulate genes associated with lineage-committed T cells and maintained stem cell– and progenitor cell–associated gene expression. In both developing and committed T cells, loss of
Bcl11b
resulted in the generation of cells that resembled natural killer (NK) cells in both phenotype and function. These NK-like cells could be expanded easily in vitro and possessed antitumor cytotoxicity, but they did not exhibit cytotoxicity against normal cells and were not tumorigenic. Because T cells are much easier to obtain from human patients than NK cells, deletion of
Bcl11b
in T cells may thus provide a source of easy-to-grow NK cells for cell-based antitumor therapies.
Controlled Injection of Spin-Triplet Supercurrents into a Strong Ferromagnet
Authors: Robinson J. W. A. , Witt J. D. S. , Blamire M. G.
Published: June 2010

Maintaining the Supercurrent

When a superconductor is placed in contact with a ferromagnet, the antiparallel spin pairs that form the supercurrent are expected to be broken almost immediately upon entering the ferromagnet, which tends to orient spins parallel to each other. If the supercurrent survives for more than a few nanometers, it is assumed that a change of pairing symmetry has taken place, with the spin-singlet pairs having been converted into spin-triplets. Magnetic inhomogeneity at the superconductor-ferromagnet interface is thought to account for this change.

Robinson
et al.

(p.
59
, published online 10 June) have now been able to observe long-ranged supercurrents in a symmetric junction consisting of a superconductor, a conical magnet, and a ferromagnet. The conical magnet layer provided the required inhomogeneity, and varying its thickness enabled control over the magnitude of the current.
Ku70 Corrupts DNA Repair in the Absence of the Fanconi Anemia Pathway
Authors: Pace Paul , Mosedale Georgina , Hodskinson Michael R. , Rosado Ivan V. , Sivasubramaniam Meera , Patel Ketan J.
Published: June 2010

Righting Repair Pathways

The genetic disease Fanconi anemia (FA) results from mutations in a series of genes involved in a DNA repair pathway that helps process the damage caused by erroneous chemical cross-links between the two strands of the DNA double helix. The double-stranded breaks in DNA that arise from such cross-links can be repaired in an error-free manner or through an error-prone repair pathway.

Pace
et al.

(p.
219
, published online 10 June) show that the FA pathway can drive repair through the error-free pathway. The FA
FANCC
gene shows a genetic interaction with a component of the error-prone repair pathway, Ku70, inhibiting its action and thereby promoting the error-free pathway.
Attachment of Mouse Hepatitis Virus to O-Acetylated Sialic Acid Is Mediated by Hemagglutinin-Esterase and Not by the Spike Protein
Authors: Langereis Martijn A. , van Vliet Arno L. W. , Boot Willemijn , de Groot Raoul J.
Published: June 2010

The members of
Betacoronavirus
phylocluster A possess two types of surface projections, one comprised of the spike protein (S) and the other of hemagglutinin-esterase (HE). Purportedly, these viruses bind to O-acetylated sialic acids (O-Ac-Sias) primarily through S, with HE serving merely as receptor-destroying enzyme. Here, we show that, in apparent contrast to human and ungulate host range variants of
Betacoronavirus-1
, murine coronaviruses actually bind to O-Ac-Sias via HE exclusively. Apparently, expansion of group A betacoronaviruses into new hosts and niches was accompanied by changes in HE ligand and substrate preference and in the roles of HE and S in Sia receptor usage.
JOB SATISFACTION OF YOUTH OUTREACH WORKERS IN HONG KONG
Authors: LEE FRANCIS WING-LIN , WONG CHRIS SUM-YEE
Published: June 2010

The promotion of job satisfaction that may lead to staff retention has always been a popular concern for human resources research. The job satisfaction and staff retention of workers in District Youth Outreaching Social Work Teams (YOTs) in Hong Kong are the themes of the present study. Through a literature review, eight facets of job satisfaction, namely Coworker Relationships, Job Complexity and Nature, Promotional Opportunity, Pay and Benefits, Work Environment, Supervision and Leadership, Role and Responsibility, and Recognition, are identified and measured among the frontline staff of the YOTs through pre-set self-administered mailed questionnaires. In relation to these facets, their intention to leave the service is also explored. The findings reveal that these workers are generally satisfied with their job (the service). At the end, some recommendations are made to promote job satisfaction and facilitate staff retention in YOTs in Hong Kong.
MENTAL HEALTH ISSUES EXPRESSED BY THE CANTONESE-CHINESE RADIO LISTENERS
Authors: CHEUNG MONIT
Published: June 2010

In order to disseminate mental health information to the Cantonese-speaking Chinese immigrants in the greater Houston area in the United States, the author initiated a local radio program to deliver 25 mental health topics to educate and stimulate the interests of the listeners. Once a week for 25 weeks, six shows were pre-recorded, and 19 shows were broadcasted live to receive phone-in calls from listeners. Among these weekly radio shows, 31 calls were received and answered. All female callers (n = 22) addressed parenting and emotional issues, while most male callers (n = 8; 89%) described being maltreated by their wife. The purpose of this qualitative practice update is to use content analysis data to inform practitioners about the unaddressed mental health needs of Chinese immigrants and make service planning suggestions based on "unheard voices".
Up and coming SIGWEB supported conferences
Authors: Deshpande Yogesh
Published: June 2010

SIGWEB supports several specialized conferences, short courses, and workshops, as well as the Annual Hypertext Conference. SIGWEB sponsored conferences focus on timely topics in applied and computational hypertext and Web disciplines and provide a place for members and the entire applied Hypermedia and Web community to exchange ideas and to meet with and expand their network of colleagues. In this article, we provide a brief overview of SIGWEB sponsored conferences, in addition to events that are in cooperation with SIGWEB.
Some philosophical implications of information-theoretic computational complexity
Authors: Chaitin G. J.
Published: June 2010

Greg Chaitin, a frequent past contributor to SIGACT News, has produced a non-technical exposition of some of the concepts and methods in information-theoretic computational complexity, and some of his results, as presented in "Information Theoretic Limitations of Formal Systems". Both a revised version of the technical paper (see SIGACT News, December 1971, page 12, for an abstract) and the non-technical exposition should appear in the literature soon. Meanwhile, we excerpt - by permission - some of the philosophical implications which we find interesting. -Ed.
A terminological proposal
Authors: Knuth D. E.
Published: June 2010

While preparing a book on combinatorial algorithms, I felt a strong need for a new technical term, a word which is essentially a one-sided version of polynomial complete. A great many problems of practical interest have the property that they are at least as difficult to solve in polynomial time as those of the Cook-Karp class KP. I needed an adjective to convey such a degree of difficulty, both formally and informally; and since the range of practical applications is so broad, I felt it would be best to establish such a term as soon as possible.
On the Aanderaa-Rosenberg Conjecture
Authors: Lipton Richard J. , Snvder Lawrence
Published: June 2010

In a recent paper [1], Rosenberg conjectures that the results found in Holt and Reingold [2], can be generalized. Suppose that graphs are presented via their adjacency matrices. Then Holt and Reingold show that any algorithm which detects whether or not a graph is strongly connected (respectively, contains a cycle) must in worst case probe 0(n
2
) entries of the given n x n adjacency matrix. Rosenberg then considers restrictions on graph property P such that any algorithm takes in worst case 0(n
2
) probes to determine whether or not a n-node graph has property P.
Modification of Aho and Ullman's correctness proof of Warshall's algorithm
Authors: Wegner Peter
Published: June 2010

Aho and Ullman's correctness proof of Warshall's algorithm (ref. 1, p. 48) is obscure and at one point incorrect. A modified version of this proof is presented.
A cross-platform test system for evolutionary black-box testing of embedded systems
Authors: Kruse Peter M. , Wegener Joachim , Wappler Stefan
Published: June 2010

When developing an electronic control unit (ECU) in a domain like the automotive industry, tests are performed on several test platforms, such as model-in-the-loop, software-in-the-loop and hardware-in-the-loop in order to find faults in early development stages. Test cases must be specified to verify the properties demanded of the developed system on these platforms. This is an expensive and non-trivial task. Evolutionary black-box testing, a recent approach to test case generation, can perform this task completely automatically. This paper describes our test system that implements evolutionary black-box testing and how to apply it to test functional and non-functional properties of an embedded system. Our test system supports the aforementioned test platforms and allows reuse of the generated test cases across them. We demonstrate the functioning of the test system in a case study with an antilock braking system.
COSMO-RS: An Alternative to Simulation for Calculating Thermodynamic Properties of Liquid Mixtures
Authors: Klamt Andreas , Eckert Frank , Arlt Wolfgang
Published: June 2010

The conductor-like screening model for realistic solvation (COSMO-RS) method has been established as a novel way to predict thermophysical data for liquid systems and has become a frequently used alternative to force field–based molecular simulation methods on one side and group contribution methods on the other. Through its unique combination of a quantum chemical treatment of solutes and solvents with an efficient statistical thermodynamics procedure for the molecular surface interactions, it enables the efficient calculation of many properties that other methods can barely predict. This review presents a short delineation of the theory, the application potential and limitations of COSMO-RS, and its most important application areas.
Ionic Liquids in Chemical Engineering
Authors: Werner Sebastian , Haumann Marco , Wasserscheid Peter
Published: June 2010

The development of engineering applications with ionic liquids stretches back to the mid-1990s when the first examples of continuous catalytic processes using ionic liquids and the first studies of ionic liquid–based extractions were published. Ever since, the use of ionic liquids has seen tremendous progress in many fields of chemistry and engineering, and the first commercial applications have been reported. The main driver for ionic liquid engineering applications is to make practical use of their unique property profiles, which are the result of a complex interplay of coulombic, hydrogen bonding and van der Waals interactions. Remarkably, many ionic liquid properties can be tuned in a wide range by structural modifications at their cation and anion. This review highlights specific examples of ionic liquid applications in catalysis and in separation technologies. Additionally, the application of ionic liquids as working fluids in process machines is introduced.
Batteries for Electric and Hybrid-Electric Vehicles
Authors: Cairns Elton J. , Albertus Paul
Published: June 2010

Batteries have powered vehicles for more than a century, but recent advances, especially in lithium-ion (Li-ion) batteries, are bringing a new generation of electric-powered vehicles to the market. Key barriers to progress include system cost and lifetime, and derive from the difficulty of making a high-energy, high-power, and reversible electrochemical system. Indeed, although humans produce many mechanical and electrical systems, the number of reversible electrochemical systems is very limited. System costs may be brought down by using cathode materials less expensive than those presently employed (e.g., sulfur or air), but reversibility will remain a key challenge. Continued improvements in the ability to synthesize and characterize materials at desired length scales, as well as to use computations to predict new structures and their properties, are facilitating the development of a better understanding and improved systems. Battery research is a fascinating area for development as well as a key enabler for future technologies, including advanced transportation systems with minimal environmental impact.
Theoretical Aspects of Immunity
Authors: Deem Michael W. , Hejazi Pooya
Published: June 2010

The immune system recognizes a myriad of invading pathogens and their toxic products. It does so with a finite repertoire of antibodies and T cell receptors. We here describe theories that quantify the dynamics of the immune system. We describe how the immune system recognizes antigens by searching the large space of receptor molecules. We consider in some detail the theories that quantify the immune response to influenza and dengue fever. We review theoretical descriptions of the complementary evolution of pathogens that occurs in response to immune system pressure. Methods including bioinformatics, molecular simulation, random energy models, and quantum field theory contribute to a theoretical understanding of aspects of immunity.