bluuebunny/crossref_metadata_2025 huggingface dataset:
An Accuracy Metric
Authors: Fisher Craig W. , Lauria Eitel J. M. , Matheus Carolyn C.
Published: January 2010

Practitioners and researchers regularly refer to error rates or accuracy percentages of databases. The former is the number of cells in error divided by the total number of cells; the latter is the number of correct cells divided by the total number of cells. However, databases may have similar error rates (or accuracy percentages) but differ drastically in the complexity of their accuracy problems. A simple percent does not provide information as to whether the errors are systematic or randomly distributed throughout the database. We expand the accuracy metric to include a randomness measure and include a probability distribution value. The proposed randomness check is based on the Lempel-Ziv (LZ) complexity measure. Through two simulation studies we show that the LZ complexity measure can clearly differentiate as to whether the errors are random or systematic. This determination is a significant first step and is a major departure from the percentage-alone technique. Once it is determined that the errors are random, a probability distribution, Poisson, is used to help address various managerial questions.
Compensated Signature Embedding for Multimedia Content Authentication
Authors: Ababneh Sufyan , Ansari Rashid , Khokhar Ashfaq
Published: January 2010

One of the main goals of digital content authentication and preservation techniques is to guarantee the originality and quality of the information. In this article, robust watermarking is used to embed content-based fragile signatures in multimedia signals to achieve efficient authentication without requiring any third-party reference or side information. To overcome the signature alteration caused by the embedding perturbation and other possible encoding operations, a closed-form compensation technique is proposed for ensuring signature consistency by employing a Lagrangian-based approach. A minimum distortion criterion is used to ensure signal quality. The effectiveness of the proposed approach is investigated with simulations of examples of image authentication in which signatures are designed to reveal tamper localization. Results using quantitative performance criteria show successful authentication over a range of robustness in embedding watermarks using both QIM-DM and spread-spectrum techniques. A comparison with two iterative compensation schemes is also presented.
New review of hypermedia and multimedia
Authors: Cunliffe Daniel , Tudhope Douglas
Published: January 2010

The 1987 ACM Hypertext conference was seen by many as the catalyst for a significant period of growth in hypertext (and subsequently hypermedia) as a coherent research area and in its impact on the general public. The period since 1987 has been punctuated by many significant events, including the development and free distribution of HyperCard, the establishing of the ACM Hypertext conference series, the founding of SIGLINK/SIGWEB, the rapid growth in the market for CD-ROM based multimedia applications, the widespread adoption of the WWW leading to the first truly large-scale hypertext application and the popularisation and commercialisation of hypertext concepts, and the emergence of web2.0. Early among those events was the launch in 1989 by Taylor Graham Publishing of the first specialist journal Hypermedia.
Book Review: Learning in Real Time by Jonathan Finkelstein
Authors: Roller Colleen
Published: January 2010

Jonathan Finkelstein says there are certain learning objectives that cannot be met without real human interaction. To remove live interaction from the learning environment is to remove the lifeblood of learning. This is why asynchronous online training solutions sometimes fall short. But when the asynchronous and the synchronous are combined in a synergistic way, the results can be highly effective.
Predictions for 2010
Authors: staff
Published: January 2010

Will GoogleWave flourish or perish? Are mobile phones going to be the next big learning devices or are they already on their way out of the e-learner's toolbox? At the start of each year, eLearn Magazine's contributors predict what changes are afoot for the coming 12 months. Here are our predictions for 2010.
Power-Efficient Software
Authors: Saxe Eric
Published: January 2010

The rate at which power-management features have evolved is nothing short of amazing. Today almost every size and class of computer system, from the smallest sensors and handheld devices to the "big iron" servers in data centers, offers a myriad of features for reducing, metering, and capping power consumption. Without these features, fan noise would dominate the office ambience, and untethered laptops would remain usable for only a few short hours (and then only if one could handle the heat), while data-center power and cooling costs and capacity would become unmanageable.
What Signals Are Removed and Retained by Using an Anomaly Field in Climatic Research?
Authors: Wang Chunzai , Song Zhenya , Qiao Fangli , Dong Shenfu
Published: January 2010

Signals in data are often detected by analyzing anomaly field that is calculated by subtracting the mean value over a time length from the data. Here we demonstrate that the anomaly calculation removes signals which satisfy that the ratio between the time length of the mean T and signals' period L is an integer (i.e., T/L=n where n is an integer) and retains other signals if the ratio is not an integer. In climatic and other studies, the time length of the mean is usually chosen as T=12 months from January to December and the mean is called the monthly climatology. Anomaly is calculated by subtracting the monthly climatology from data. This anomaly calculation thus removes the climatic signals with the periods of 12, 6, 4, 3, 2.4, and 2 months which correspond to (12 months)/n with n=1, 2, 3, 4, 5, and 6, respectively, whereas it retains other signals such as those with the periods of 11, 10, 9, 8, 7, and 5 months. This paper suggests that one should be cautious when an anomaly field is used in research. The conventional notion is that the monthly anomaly calculation removes the annual cycle. However, here we show that the anomaly calculation removes all signals as long as the time length of the mean is an integer multiple of signals' period.
On the Beams with External Auxetic Patches
Authors: Chiroiu Veturia , Munteanu Ligia , Donescu Ştefania
Published: January 2010

The paper discusses the behavior of beams with external damping patches made of auxetic materials. The damping force is modeled by using the nonlocal theory. Unlike the local models, the nonlocal damping force is modeled as a weighted average of the velocity field over the spatial domain, determined by a kernel function based on distance measures. The performance with respect to the eigenvalues is discussed next, in order to avoid resonance. The optimization is performed by determining the location of patches from maximizing the eigenvalues, or the gap between them.
Analytical Expression for Sound Transmission Loss Calculation: An Improvement to the Existing Method after Singh and Katra
Authors: Yahya Iwan
Published: January 2010

An analytical expression for measuring of sound transmission loss (TL) has been developed by using two microphones, an impedance tube and an impulse sound source as a proposed improvement to the existing procedure after Singh and Katra (1978). The calculation procedure is based on the autospectrum of short‐time signals captured by the two microphones placed on two opposite positions from test sample while the sound source is on its surface. No spectral decomposition is required and the TL is calculated directly from the autospectrums of captured signals.
Ghrelin and Functional Dyspepsia
Authors: Akamizu Takashi , Iwakura Hiroshi , Ariyasu Hiroyuki , Kangawa Kenji
Published: January 2010

The majority of patients with dyspepsia have no identifiable cause of their disease, leading to a diagnosis of functional dyspepsia (FD). While a number of different factors affect gut activity, components of the nervous and endocrine systems are essential for normal gut function. Communication between the brain and gut occurs via direct neural connections or endocrine signaling events. Ghrelin, a peptide produced by the stomach, affects gastric motility/emptying and secretion, suggesting it may play a pathophysiological role in FD. It is also possible that the functional abnormalities in FD may affect ghrelin production in the stomach. Plasma ghrelin levels are reported to be altered in FD, correlating with FD symptom score. Furthermore, some patients with FD suffer from anorexia with body-weight loss. As ghrelin increases gastric emptying and promotes feeding, ghrelin therapy may be a new approach to the treatment of FD.
Gene-Gene Interactions in the Folate Metabolic Pathway and the Risk of Conotruncal Heart Defects
Authors: Lupo Philip J. , Goldmuntz Elizabeth , Mitchell Laura E.
Published: January 2010

Conotruncal and related heart defects (CTRD) are common, complex malformations. Although there are few established risk factors, there is evidence that genetic variation in the folate metabolic pathway influences CTRD risk. This study was undertaken to assess the association between inherited (i.e., case) and maternal gene-gene interactions in this pathway and the risk of CTRD. Case-parent triads (n=727), ascertained from the Children's Hospital of Philadelphia, were genotyped for ten functional variants of nine folate metabolic genes. Analyses of inherited genotypes were consistent with the previously reported association betweenMTHFRA1298C and CTRD (adjustedP=.02), but provided no evidence that CTRD was associated with inherited gene-gene interactions. Analyses of the maternal genotypes provided evidence of aMTHFRC677T/CBS844ins68 interaction and CTRD risk (unadjustedP=.02). This association is consistent with the effects of this genotype combination on folate-homocysteine biochemistry but remains to be confirmed in independent study populations.
Cholesteryl Ester Transfer Protein and Mortality in Patients Undergoing Coronary Angiography
Authors: Ritsch Andreas , Scharnagl Hubert , Eller Philipp , Tancevski Ivan , Duwensee Kristina , Demetz Egon , Sandhofer Anton , Boehm Bernhard O. , Winkelmann Bernhard R. , Patsch Josef R. , März Winfried
Published: January 2010

Background—

The role of cholesteryl ester transfer protein (CETP) in the development of atherosclerosis is still open to debate. In the Investigation of Lipid Level Management to Understand its Impact in Atherosclerotic Events (ILLUMINATE) trial, inhibition of CETP in patients with high cardiovascular risk was associated with increased high-density lipoprotein levels but increased risk of cardiovascular morbidity and mortality. In this report, we present a prospective observational study of patients referred to coronary angiography in which CETP was examined in relation to morbidity and mortality.

Methods and Results—

CETP concentration was determined in 3256 participants of the Ludwigshafen Risk and Cardiovascular Health (LURIC) study who were referred to coronary angiography at baseline between 1997 and 2000. Median follow-up time was 7.75 years. Primary and secondary end points were cardiovascular and all-cause mortality, respectively. CETP levels were higher in women and lower in smokers, in diabetic patients, and in patients with unstable coronary artery disease, respectively. In addition, CETP levels were correlated negatively with high-sensitivity C-reactive protein and interleukin-6. After adjustment for age, sex, medication, coronary artery disease status, cardiovascular risk factors, and diabetes mellitus, the hazard ratio for death in the lowest CETP quartile was 1.33 (1.07 to 1.65;
P
=0.011) compared with patients in the highest CETP quartile. Corresponding hazard ratios for death in the second and third CETP quartiles were 1.17 (0.92 to 1.48;
P
=0.19) and 1.10 (0.86 to 1.39;
P
=0.46), respectively.

Conclusions—

We interpret our data to suggest that low endogenous CETP plasma levels per se are associated with increased cardiovascular and all-cause mortality, challenging the rationale of pharmacological CETP inhibition.
Angiotensin Receptor Agonistic Autoantibody–Mediated Tumor Necrosis Factor-α Induction Contributes to Increased Soluble Endoglin Production in Preeclampsia
Authors: Zhou Cissy Chenyi , Irani Roxanna A. , Zhang Yujin , Blackwell Sean C. , Mi Tiejuan , Wen Jiaming , Shelat Harnath , Geng Yong-Jian , Ramin Susan M. , Kellems Rodney E. , Xia Yang
Published: January 2010

Background—

Preeclampsia is a prevalent life-threatening hypertensive disorder of pregnancy. The circulating antiangiogenic factor, soluble endoglin (sEng), is elevated in the blood circulation of women with preeclampsia and contributes to disease pathology; however, the underlying mechanisms responsible for its induction in preeclampsia are unknown.

Methods and Results—

Here, we discovered that a circulating autoantibody, the angiotensin receptor agonistic autoantibody (AT
1
-AA), stimulates sEng production via AT
1
angiotensin receptor activation in pregnant mice but not in nonpregnant mice. We subsequently demonstrated that the placenta is a major source contributing to sEng induction in vivo and that AT
1
-AA–injected pregnant mice display impaired placental angiogenesis. Using drug screening, we identified tumor necrosis factor-α as a circulating factor increased in the serum of autoantibody-injected pregnant mice contributing to AT
1
-AA–mediated sEng induction in human umbilical vascular endothelial cells. Subsequently, among all the drugs screened, we found that hemin, an inducer of heme oxygenase, functions as a break to control AT
1
-AA–mediated sEng induction by suppressing tumor necrosis factor-α signaling in human umbilical vascular endothelial cells. Finally, we demonstrated that the AT
1
-AA–mediated decreased angiogenesis seen in human placenta villous explants was attenuated by tumor necrosis factor-α–neutralizing antibodies, soluble tumor necrosis factor-α receptors, and hemin by abolishing both sEng and soluble fms-like tyrosine kinase-1 induction.

Conclusions—

Our findings demonstrate that AT
1
-AA–mediated tumor necrosis factor-α induction, by overcoming its negative regulator, heme oxygenase-1, is a key underlying mechanism responsible for impaired placental angiogenesis by inducing both sEng and soluble fms-like tyrosine kinase-1 secretion from human villous explants. Our results provide important new targets for diagnosis and therapeutic intervention in the management of preeclampsia.
Angiotensin II Type 1 Receptor–Activated Caspase-3 Through Ras/Mitogen-Activated Protein Kinase/Extracellular Signal-Regulated Kinase in the Rostral Ventrolateral Medulla Is Involved in Sympathoexcitation in Stroke-Prone Spontaneously Hypertensive Rats
Authors: Kishi Takuya , Hirooka Yoshitaka , Konno Satomi , Ogawa Kiyohiro , Sunagawa Kenji
Published: January 2010

In the rostral ventrolateral medulla (RVLM), angiotensin II-derived superoxide anions, which increase sympathetic nerve activity, induce a pressor response by activating the p38 mitogen-activated protein kinase (p38 MAPK) and extracellular signal-regulated kinase (ERK) pathway. The small G protein Ras mediates a caspase-3–dependent apoptotic pathway through p38 MAPK, ERK, and c-Jun N-terminal kinase. We hypothesized that angiotensin II type 1 receptors activate caspase-3 through the Ras/p38 MAPK/ERK/c-Jun N-terminal kinase pathway in the RVLM and that this pathway is involved in sympathoexcitation in stroke-prone spontaneously hypertensive rats (SHRSP), a model of human hypertension. The activities of Ras, p38 MAPK, ERK, and caspase-3 in the RVLM were significantly higher in SHRSP (14 to 16 weeks old) than in age-matched Wistar-Kyoto rats (WKY). The mitochondrial apoptotic proteins Bax and Bad in the RVLM were significantly increased in SHRSP compared with WKY. c-Jun N-terminal kinase activity did not differ between SHRSP and WKY. In SHRSP, intracerebroventricular infusion of a Ras inhibitor significantly reduced sympathetic nerve activity and improved baroreflex sensitivity, partially because of inhibition of the Ras/p38 MAPK/ERK, Bax, Bad, and caspase-3 pathway in the RVLM. Intracerebroventricular infusion of a caspase-3 inhibitor also inhibited sympathetic nerve activity and improved baroreflex sensitivity in SHRSP. Intracerebroventricular infusion of an angiotensin II type 1 receptor blocker in SHRSP partially inhibited the Ras/p38 MAPK/ERK, Bax, Bad, and caspase-3 pathway in the RVLM. These findings suggest that in SHRSP, angiotensin II type 1 receptor-activated caspase-3 acting through the Ras/p38 MAPK/ERK pathway in the RVLM might be involved in sympathoexcitation, which in turn plays a crucial role in the pathogenesis of hypertension.
Angiotensin I–Converting Enzyme Inhibitors Are Allosteric Enhancers of Kinin B1 and B2 Receptor Function
Authors: Erdös Ervin G. , Tan Fulong , Skidgel Randal A.
Published: January 2010

The beneficial effects of angiotensin I-converting enzyme (ACE) inhibitors go beyond the inhibition of ACE to decrease angiotensin (Ang) II or increase kinin levels. ACE inhibitors also affect kinin B1 and B2 receptor (B1R and B2R) signaling, which may underlie some of their therapeutic usefulness. They can indirectly potentiate the actions of bradykinin (BK) and ACE-resistant BK analogs on B2Rs to elevate arachidonic acid and NO release in laboratory experiments. Studies indicate that ACE inhibitors and some Ang metabolites increase B2R functions as allosteric enhancers by inducing a conformational change in ACE. This is transmitted to B2Rs via heterodimerization with ACE on the plasma membrane of cells. ACE inhibitors are also agonists of the B1R, at a Zn-binding sequence on the second extracellular loop that differs from the orthosteric binding site of the des-Arg-kinin peptide ligands. Thus, ACE inhibitors act as direct allosteric B1R agonists. When ACE inhibitors enhance B2R and B1R signaling, they augment NO production. Enhancement of B2R signaling activates endothelial NO synthase, yielding a short burst of NO; activation of B1Rs results in a prolonged high output of NO by inducible NO synthase. These actions, outside inhibiting peptide hydrolysis, may contribute to the pleiotropic therapeutic effects of ACE inhibitors in various cardiovascular disorders.
The Impact of Microsomal Prostaglandin E Synthase 1 on Blood Pressure Is Determined by Genetic Background
Authors: Facemire Carie S. , Griffiths Robert , Audoly Laurent P. , Koller Beverly H. , Coffman Thomas M.
Published: January 2010

Prostaglandin (PG)E
2
has multiple actions that may affect blood pressure. It is synthesized from arachidonic acid by the sequential actions of phospholipases, cyclooxygenases, and PGE synthases. Although microsomal PGE synthase (mPGES)1 is the only genetically verified PGE synthase, results of previous studies examining the consequences of mPGES1 deficiency on blood pressure (BP) are conflicting. To determine whether genetic background modifies the impact of mPGES1 on BP, we generated mPGES1
−/−
mice on 2 distinct inbred backgrounds, DBA/1lacJ and 129/SvEv. On the DBA/1 background, baseline BP was similar between wild-type (WT) and mPGES1
−/−
mice. By contrast, on the 129 background, baseline BPs were significantly higher in mPGES1
−/−
animals than WT controls. During angiotensin II infusion, the DBA/1 mPGES1
−/−
and WT mice developed mild hypertension of similar magnitude, whereas 129-mPGES1
−/−
mice developed more severe hypertension than WT controls. DBA/1 animals developed only minimal albuminuria in response to angiotensin II infusion. By contrast, WT 129 mice had significantly higher levels of albumin excretion than WT DBA/1 and the extent of albuminuria was further augmented in 129 mPGES1
−/−
animals. In WT mice of both strains, the increase in urinary excretion of PGE
2
with angiotensin II was attenuated in mPGES1
−/−
animals. Urinary excretion of thromboxane was unaffected by angiotensin II in the DBA/1 lines but increased more than 4-fold in 129 mPGES1
−/−
mice. These data indicate that genetic background significantly modifies the BP response to mPGES1 deficiency. Exaggerated production of thromboxane may contribute to the robust hypertension and albuminuria in 129 mPGES1-deficient mice.
Using Economy of Means to Evolve Transition Rules within 2D Cellular Automata
Authors: Ripps David L.
Published: January 2010

Running a cellular automaton (CA) on a rectangular lattice is a time-honored method for studying artificial life on a digital computer. Commonly, the researcher wishes to investigate some specific or general mode of behavior, say, the ability of a coherent pattern of points to glide within the lattice, or to generate copies of itself. This technique has a problem: how to design the transitions table—the set of distinct rules that specify the next content of a cell from its current content and that of its near neighbors. Often the table is painstakingly designed manually, rule by rule. The problem is exacerbated by the potentially vast number of individual rules that need be specified to cover all combinations of center and neighbors when there are several symbols in the alphabet of the CA. In this article a method is presented to have the set of rules evolve automatically while running the CA. The transition table is initially empty, with rules being added as the need arises. A novel principle drives the evolution: maximum economy of means—maximizing the reuse of rules introduced on previous cycles. This method may not be a panacea applicable to all CA studies. Nevertheless, it is sufficiently potent to evolve sets of rules and associated patterns of points that glide (periodically regenerate themselves at another location) and to generate gliding “children” that then “mate” by collision.
Personality, Mental Health and Glossolalia
Authors: Francis L.J. , Kay William K.
Published: January 2010

This article reports on a survey of young men and women training for Pentecostal ministry. The survey was designed to test the relationship between glossolalia, or speaking in tongues, and personality. Personality theory, briefly outlined below, is complex and divided into several schools. For this reason it is necessary to show how findings derived from one school may be interpreted differently by another. Nevertheless, the general outline of previous work is clear. Most critically important for young men and women preparing for Pentecostal ministry is the fact that some research has questioned the mental health of those who speak in tongues. This article is able to show that, on the contrary, those who speak in tongues in the current sample under study are less neurotic than the general population. In order to demonstrate the validity of this thesis, this article will first outline the optional psychological theories of personality with their explanations of mental health and mental illness, then delineate the findings of various psychological studies of glossolalia, and finally present the results of our study of Pentecostal ministry candidates from a data analysis of the Eysenck Personality Questionnaire.
God Present in a Confused Situation: The Mixed Influence of the Charismatic Movement on Classical Pentecostalism in the United States
Authors: Macchia Frank D.
Published: January 2010

This confused response to the Charismatic movement2 by an official of the Assemblies of God is typical of what many classical Pentecostals in the United States have felt in their struggle over the past three decades to come to terms with the obvious proliferation of extraordinary signs and gifts of the Holy Spirit among members of mainline churches. In the past, Pentecostals viewed these churches as the chief opponents of the latter-day bestowal of supernatural signs and wonders. Apparently, without the permission of Pentecostals, the Spirit of God was suddenly being felt in Charismatic Renewal among members of major Protestant churches and, most surprisingly for Pentecostals, in the Roman Catholic Church. The Pentecostal confusion, however, was due not only to the unexpected work of the Spirit among alleged opponents of revival, but also to the influence that these Renewal movements were having on many classical Pentecostals. In other words, Pentecostals not only had to wrestle with the dramatic work of the Spirit in the mainline churches, they also had to come to terms with the possibility that the movement may serve as a source of renewal for Pentecostal churches. This confusion was rooted in the Pentecostal ambivalence toward a Renewal movement that both repelled and influenced the classical Pentecostal churches.
Feedback: the Charismatic Renewal
Authors: Hocken Peter D.
Published: January 2010

The Theological Commission of the Charismatic Renewal in the Catholic Church of Germany is to be commended for its detailed tackling of an important topic that most Churches and denominations affected by "extraordinary bodily phenomena" are neither studying nor evaluating in any serious way. As a fellow Catholic theologian, I wish to reflect on the importance of this document "Concerning Extraordinary Bodily Phenomena in the Context of Spiritual Occurrences" published in the previous issue of PNEEWA1 and to begin by recognizing its valuable contribution.
An example of a 'New Age' interpretation of the Bible
Authors: Steyn H.C.
Published: January 2010

This article sketches the framework in terms of the New Age movement, the Ancient Wisdom tradition and the astrological background in which a 'NewAge' interpretation of the Bible is made by esotericist Corrine Heline. Her interpretation of the Christ and his mission on earth is explored and attention is given to the concept of salvation in this context. In conclusion, the necessary presuppositions for the validity of this type of exegesis are considered.
The implied reader of Luke's gospel
Authors: Okorie A.M.
Published: January 2010

The notion of implied reader is discussed with reference to modern theorists like Booth, Iser, Fowler and Prince. A description of the implied reader in Luke's gospel is then constructed from the clues that Luke's narrative provides.
CloudSat Precipitation Profiling Algorithm—Model Description
Authors: Mitrescu Cristian , L’Ecuyer Tristan , Haynes John , Miller Steven , Turk Joseph
Published: January 2010

Identifying and quantifying the intensity of light precipitation at global scales is still a difficult problem for most of the remote sensing algorithms in use today. The variety of techniques and algorithms employed for such a task yields a rather wide spectrum of possible values for a given precipitation event, further hampering the understanding of cloud processes within the climate. The ability of CloudSat’s millimeter-wavelength Cloud Profiling Radar (CPR) to profile not only cloud particles but also light precipitation brings some hope to the above problems. Introduced as version zero, the present work uses basic concepts of detection and retrieval of light precipitation using spaceborne radars. Based on physical principles of remote sensing, the radar model relies on the description of clouds and rain particles in terms of a drop size distribution function. Use of a numerical model temperature and humidity profile ensures the coexistence of mixed phases otherwise undetected by the CPR. It also provides grounds for evaluating atmospheric attenuation, important at this frequency. Related to the total attenuation, the surface response is used as an additional constraint in the retrieval algorithm. Practical application of the profiling algorithm includes a 1-yr preliminary analysis of global rainfall incidence and intensity. These results underscore once more the role of CloudSat rainfall products for improving and enhancing current estimates of global light rainfall, mostly at higher latitudes, with the goal of understanding its role in the global energy and water cycle.
A Systematic Error in Plane-Parallel Radiative Transfer Calculations
Authors: McLinden Chris A. , Bourassa Adam E.
Published: January 2010

Systematic errors in plane-parallel radiative transfer calculations are examined in the context of limb radiance. Calculation of the multiple-scattering component of limb radiance using plane-parallel geometry can lead to a systematic overestimation that increases with surface albedo and tangent height. It is demonstrated that the cause of this is the overestimate of the surface-reflected radiance component. A simple yet effective correction is introduced that reduces these errors from 4%–8% to <2%. This error source may manifest itself in any application of radiative transfer calculations employing plane-parallel geometry.
Winter-to-Winter Recurrence of Sea Surface Temperature Anomalies in the Northern Hemisphere
Authors: Zhao Xia , Li Jianping
Published: January 2010

The spatiotemporal characteristics of the winter-to-winter recurrence (WWR) of sea surface temperature anomalies (SSTA) in the Northern Hemisphere (NH) are comprehensively studied through lag correlation analysis. On this basis the relationships between the SSTA WWR and the WWR of the atmospheric circulation anomalies, El Niño–Southern Oscillation (ENSO), and SSTA interdecadal variability are also investigated.

Results show that the SSTA WWR occurs over most parts of the North Pacific and Atlantic Oceans, but the spatiotemporal distributions of the SSTA WWR are distinctly different in these two oceans. Analyses indicate that the spatiotemporal distribution of the SSTA WWR in the North Atlantic Ocean is consistent with the spatial distribution of the seasonal cycle of its mixed layer depth (MLD), whereas that in the North Pacific Ocean, particularly the recurrence timing, cannot be fully explained by the change in the MLD between winter and summer in some regions. In addition, the atmospheric circulation anomalies also exhibit the WWR at the mid–high latitude of the NH, which is mainly located in eastern Asia, the central North Pacific, and the North Atlantic. The sea level pressure anomalies (SLPA) in the central North Pacific are essential for the occurrence of the SSTA WWR in this region. Moreover, the strongest positive correlation occurs when the SLPA lead SSTA in the central North Pacific by 1 month, which suggests that the atmospheric forcing on the ocean may play a dominant role in this region. Therefore, the “reemergence mechanism” is not the only process influencing the SSTA WWR, and the WWR of the atmospheric circulation anomalies may be one of the causes of the SSTA WWR in the central North Pacific. Finally, the occurrence of the SSTA WWR in the NH is closely related to SSTA interdecadal variability in the NH, but it is linearly independent of ENSO.
The Sensitivity of Mountain Snowpack Accumulation to Climate Warming
Authors: Minder Justin R.
Published: January 2010

Controls on the sensitivity of mountain snowpack accumulation to climate warming (λS) are investigated. This is accomplished using two idealized, physically based models of mountain snowfall to simulate snowpack accumulation for the Cascade Mountains under current and warmed climates. Both models are forced from sounding observations. The first model uses the linear theory (LT) model of orographic precipitation to predict precipitation as a function of the incoming flow characteristics and uses the sounding temperatures to estimate the elevation of the rain–snow boundary, called the melting level (ML). The second “ML model” uses only the ML from the sounding and assumptions of uniform and constant precipitation. Both models simulate increases in precipitation intensity and elevated storm MLs under climate warming. The LT model predicts a 14.8%–18.1% loss of Cascade snowfall per degree of warming, depending on the vertical structure of the warming. The loss of snowfall is significantly greater, 19.4%–22.6%, if precipitation increases are neglected. Comparing the two models shows that the predominant control on λS is the relationship between the distribution of storm MLs and the distribution of topographic area with elevation. Although increases in precipitation due to warming may act to moderate λS, the loss of snow accumulation area profoundly limits the ability of precipitation increases to maintain the snowpack under substantial climate warming (beyond 1°–2°C). Circulation changes may act to moderate or exacerbate the loss of mountain snowpack under climate change via impacts on orographic precipitation enhancement.
Baroclinic Flow around Planetary Islands in a Double Gyre: A Mechanism for Cross-Gyre Flow
Authors: Pedlosky Joseph
Published: January 2010

A quasigeostrophic, two-layer model is used to study the baroclinic circulation around a thin, meridionally elongated island. The flow is driven by either buoyancy forcing or wind stress, each of whose structure would produce an antisymmetric double-gyre flow. The ocean bottom is flat. When the island partially straddles the intergyre boundary, fluid from one gyre is forced to flow into the other. The amount of the intergyre flow depends on the island constant, that is, the value of the geostrophic streamfunction on the island in each layer. That constant is calculated in a manner similar to earlier studies and is determined by the average, along the meridional length of the island, of the interior Sverdrup solution just to the east of the island.

Explicit solutions are given for both buoyancy and wind-driven flows. The presence of an island of nonzero width requires the determination of the baroclinic streamfunction on the basin’s eastern boundary. The value of the boundary term is proportional to the island’s area. This adds a generally small additional baroclinic intergyre flow. In all cases, the intergyre flow produced by the island is not related to topographic steering of the flow but rather the pressure anomaly on the island as manifested by the barotropic and baroclinic island constants. The vertical structure of the flow around the island is a function of the parameterization of the vertical mixing in the problem and, in particular, the degree to which long baroclinic Rossby waves can traverse the basin before becoming thermally damped.
A New Three-Dimensional Visualization System for Combining Aircraft and Radar Data and Its Application to RICO Observations
Authors: Arthur Dan K. , Lasher-Trapp Sonia , Abdel-Haleem Ayman , Klosterman Nicholas , Ebert David S.
Published: January 2010

The analysis of diverse datasets from meteorological field campaigns often involves the use of separate 1D or combined 2D plots from various applications, making the determination of spatial and temporal relationships and correlations among these data, and the overall synthesis of information, extremely challenging. Presented here is a new 3D visualization tool, the Aircraft and Radar Data Collocation and Analysis in 3D (ARCA3D), that can combine data collected from different sources and at different scales, utilizing advanced visualization and user interface techniques, which allows for easier comparison and synthesis of such disparate data. The 3D tool is demonstrated with aircraft-based microphysical probe data and ground-based dual-polarization radar data all collected during the Rain in Cumulus over the Ocean (RICO) field campaign. The 3D volumes of radar data can be interactively selected and quantitatively probed, while aircraft-measured variables can be viewed along the aircraft track plotted within the 3D radar volumes or plotted as time series within regions of interest relative to the radar echoes. The greatest benefits of the new software, the 3D viewing of large radar and aircraft datasets with user-driven controls, are difficult to communicate here in a static, 2D written medium, but the application of the tool toward a research problem is presented to elucidate the impacts of these benefits. The ARCA3D software is used to investigate the possible role of giant aerosol particles in the development of precipitation in trade wind cumuli. The temporal trends in the spatial location of the maximum differential reflectivity echoes within the clouds are examined with respect to the ambient giant aerosol number concentration and the measured cloud-base droplet number concentrations on 10 days. The results indicate that in trade wind cumuli of sufficient depth, giant aerosol may determine the original location of the earliest differential reflectivity maximum echo, and thus the first raindrops when present in higher number concentrations. However, when the giant aerosol are less plentiful, the number of cloud droplets activated above the cloud base may also play a role in determining the location of the earliest maximum differential reflectivity echo, and thus the earliest raindrops, in these trade wind cumuli.
Calibration, Response, and Hysteresis in Deep-Sea Dissolved Oxygen Measurements
Authors: Edwards Bradley , Murphy David , Janzen Carol , Larson Nordeen
Published: January 2010

Accurately measuring the dissolved oxygen concentration in the ocean has been the subject of considerable research. Traditionally, the calibration and correction of profiling oxygen measurements has centered on static, steady-state errors, leaving dynamic or time-dependent errors in the sensor response largely untreated. This study evaluates a reengineered Sea-Bird Electronics dissolved-oxygen Clark electrode (SBE 43) and demonstrates the characterization of sensor time response over oceanographic temperatures and pressures as well as treating a time-dependent, pressure-induced effect observed as hysteresis, most notably in deep-ocean oxygen profiles. The effects of temperature and pressure on sensor response are measured separately and then combined into an expression for evaluating an in situ time constant. The physics of the pressure-induced hysteresis in oxygen sensors are discussed and modeled for many individual sensors in several locations throughout the world’s oceans. This effort reduces the underlying uncertainty of Clark oxygen sensors to approximately 0.1% of the measured signal, which is equivalent to the accuracy of the chemical calibration standard.
Effect of Two-Way Air–Sea Coupling in High and Low Wind Speed Regimes
Authors: Chen Sue , Campbell Tim J. , Jin Hao , Gaberšek Saša , Hodur Richard M. , Martin Paul
Published: January 2010

A recent advance in the Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS) is described and used to study two-way air–sea coupling and its impact on two different weather scenarios. The first case examines the impact of a hurricane-induced cold ocean wake on simulated changes in the structure of Hurricane Katrina. The second case investigates the effect of wind- and current-induced island wakes and their impact on the local electromagnetic (EM) and acoustic propagation characteristics in the Southern California Bight region. In the Katrina case, both the atmosphere and ocean show a strong response from air–sea interaction. The model results show that wind-induced turbulent mixing, vertical advection, and horizontal advection are the three primary causes of the development of the trailing cold ocean wake. A distinct spatial separation is seen in these three primary forcing terms that are generating the bulk of the cooling in the ocean mixed layer. An asymmetric tropical cyclone structure change has been documented in detail from a more realistic, full physics, and tightly coupled model. These changes include a broadening of the eye, a reduced radius of hurricane-force wind, and a pronounced inner-core dry slot on the west side of the storm. In the island wake experiment, many finescale variations in the wind, current, and static stability structure resulting from the two-way interaction are described. These variations take the form of narrow vorticity and temperature anomalies that are found to reside in the ocean and atmosphere well downwind from the Channel Islands. Upwind differences in the lower-atmospheric wind and thermal structure also arise and are found to have a small impact on the lee-flow structure and EM characteristics of the southernmost Channel Islands.
Reevaluating the Role of the Saharan Air Layer in Atlantic Tropical Cyclogenesis and Evolution
Authors: Braun Scott A.
Published: January 2010

The existence of the Saharan air layer (SAL), a layer of warm, dry, dusty air frequently present over the tropical Atlantic Ocean, has long been appreciated. The nature of its impacts on hurricanes remains unclear, with some researchers arguing that the SAL amplifies hurricane development and with others arguing that it inhibits it. The potential negative impacts of the SAL include 1) vertical wind shear associated with the African easterly jet; 2) warm air aloft, which increases thermodynamic stability at the base of the SAL; and 3) dry air, which produces cold downdrafts. Multiple NASA satellite datasets and NCEP global analyses are used to characterize the SAL’s properties and evolution in relation to tropical cyclones and to evaluate these potential negative influences. The SAL is shown to occur in a large-scale environment that is already characteristically dry as a result of large-scale subsidence. Strong surface heating and deep dry convective mixing enhance the dryness at low levels (primarily below ∼700 hPa), but moisten the air at midlevels. Therefore, mid- to-upper-level dryness is not generally a defining characteristic of the SAL, but is instead often a signature of subsidence. The results further show that storms generally form on the southern side of the jet, where the background cyclonic vorticity is high. Based upon its depiction in NCEP Global Forecast System meteorological analyses, the jet often helps to form the northern side of the storms and is present to equal extents for both strengthening and weakening storms, suggesting that jet-induced vertical wind shear may not be a frequent negative influence. Warm SAL air is confined to regions north of the jet and generally does not impact the tropical cyclone precipitation south of the jet.

Composite analyses of the early stages of tropical cyclones occurring in association with the SAL support the inferences from the individual cases noted above. Furthermore, separate composites for strongly strengthening and for weakening storms show few substantial differences in the SAL characteristics between these two groups, suggesting that the SAL is not a determinant of whether a storm will intensify or weaken in the days after formation. Key differences between these cases are found mainly at upper levels where the flow over strengthening storms allows for an expansive outflow and produces little vertical shear, while for weakening storms, the shear is stronger and the outflow is significantly constrained.
Inhomogeneous Background Error Modeling and Estimation over Antarctica
Authors: Michel Yann , Auligné Thomas
Published: January 2010

The structure of the analysis increments in a variational data assimilation scheme is strongly driven by the formulation of the background error covariance matrix, especially in data-sparse areas such as the Antarctic region. The gridpoint background error modeling in this study makes use of regression-based balance operators between variables, empirical orthogonal function decomposition to define the vertical correlations, gridpoint variances, and high-order efficient recursive filters to impose horizontal correlations. A particularity is that the regression operators and the recursive filters have been made spatially inhomogeneous. The computation of the background error statistics is performed with the Weather Research and Forecast (WRF) model from a set of forecast differences. The mesoscale limited-area domains of interest cover Antarctica. Inhomogeneities of background errors are shown to be related to the particular orography and physics of the area. Differences seem particularly pronounced between ocean and land boundary layers.
A Cost-Benefit Study of a Breaking the Cycle Program for Juveniles
Authors: Cowell Alexander J. , Lattimore Pamela K. , Krebs Christopher P.
Published: January 2010

The authors present a cost-benefit analysis of a Juvenile Breaking the Cycle (JBTC) program in Oregon designed to provide juvenile justice system monitoring and coordinated treatment and services to youth who are assessed as at high risk for recidivism and substance use. Detailed cost analyses are presented for youth in the JBTC program and a comparison group. Multivariate models for all costs combined indicate that the costs per JBTC youth are much higher than for the comparison group 6 to 12 months after intake. Twelve to 18 months after intake, the difference in juvenile justice costs between the two groups is negligible. These findings suggest that decision makers should not expect any additional case management and treatment costs to be offset immediately by reductions in juvenile justice costs. However, evidence suggests that juvenile justice costs may eventually be at least equivalent to usual care.
Using Multi-agent Geo-simulation Techniques for the Detection of Risky Areas for Trains
Authors: Mekni Mehdi , Sahli Nabil , Moulin Bernard , Haddad Hedi
Published: January 2010

A transportation system is spatially and functionally distributed; its subsystems have a high degree of autonomy and are in constant interaction with each other and with the surrounding geographic environment. Modeling and simulating such systems in large-scale geographic spaces is a complex process. In this paper we address the domain of railway systems, and more particularly the problem of detecting risky areas along railroads. This requires that we consider a variety of static and dynamic variables, including train characteristics, hazardous events (e.g. rock-falls), and the properties of the large-scale geographic environment, as well as weather conditions. This simulation enables us to recommend speed limits in risky areas while taking into account all of the aforementioned factors. Since statistical and analytical models are not appropriate to represent such a complex process in which spatial constraints are of high importance, we adopted a multi-agent geo-simulation (MAGS) approach that facilitates the simulation of complex systems in large-scale geo-referenced environments. In this paper, we present Train-MAGS, an agent-based geo-simulation tool that simulates train behaviors in risky areas in large-scale virtual geographic environments. We also demonstrate how risky areas can be detected in real time using an agent-based approach. This work also illustrates how the application of artificial intelligence techniques, such as the MAGS approach, provides interesting perspectives of realistic and plausible simulations aimed at improving the functioning, the efficiency, and the safety of the transportation systems.
The Impact of Perceived Group Support on the Effectiveness of an HIV Prevention Intervention for African American Women
Authors: Belgrave Faye Z. , Corneille Maya , Hood Kristina , Foster-Woodson Julia , Fitzgerald Angela
Published: January 2010

The enormous HIV/AIDS disparity among African American women and women in other ethnic groups dictates the need to implement the most effective HIV prevention interventions. This study examined the impact of perceived group support on HIV protective behaviors (i.e., attitudes and behaviors related to condom use, alcohol, and drugs) of African American women participating in an HIV prevention intervention. Participants were 398 heterosexual, unmarried African American women older than 18 years who agreed to participate in Sisters Informing Sisters on Topics about AIDS, a widely used HIV prevention program for African American women. Regression analyses revealed that higher perceived support contributed to (1) higher condom negotiation efficacy, (2) higher condom use efficacy, (3) consistent condom use for sexually active participants, (4) higher perception of drug harmfulness, and (5) drug disapproval at posttest. These effects were found while controlling for pretest measures of condom and drug attitudes and use along with age, partner status, length of relationship, and education. The findings suggest that HIV intervention efforts should attend to ways in which women receive and provide support to one another.