bluuebunny/crossref_metadata_2025 huggingface dataset:
Vacuum pressure distribution and pore pressure variation in ground improved by vacuum preloading
Authors: Qiu Q. C. , Mo H. H. , Dong Z. L.
Published: March 2008

This paper presents the difference between vacuum pressure and pore pressure reduction for vacuum preloading projects. The experimental results show that the pattern of the fluid flow under vacuum pressure can be classified into three categories—a single-phase water flow, an air–water two-phase flow, and a single-phase air flow. The field test results show that the vacuum pressure reaches the highest value at the ground level and the measured gradients of the vacuum pressure in the vertical direction are approximately 11 kPa/m. It is demonstrated that (i) the treatment area of vacuum preloading cannot be sealed and does not need to be airtight, (ii) the air–water mixture is drawn out from the treatment area under vacuum pressure and the groundwater level drops owing to the presence of air in practice, and (iii) there is an air–water two-phase flow in the unsaturated zone during preloading. The study shows that (i) the vacuum pressure is only a part of the pore pressure reduction along the depth of improving soil; and (ii) the vacuum pressure induces the soil to undergo isotropic consolidation, whereas the pore pressure reduction that is greater than the atmospheric pressure induces the soil to undergo one-dimensional consolidation.
Shear modulus and material damping of municipal solid waste based on large-scale cyclic triaxial testing
Authors: Zekkos Dimitrios , Bray Jonathan D. , Riemer Michael F.
Published: March 2008

Representative dynamic properties of municipal solid waste (MSW) are required to perform reliable seismic analyses of MSW landfills. A comprehensive large-scale cyclic triaxial laboratory testing program was performed on MSW retrieved from a landfill in the San Francisco Bay area to evaluate the small-strain shear modulus, and strain-dependent normalized shear modulus reduction and material damping ratio relationships of MSW. The effects of waste composition, confining stress, unit weight, time under confinement, and loading frequency on these dynamic properties were evaluated. The small-strain shear modulus depends primarily on waste composition, confining stress, unit weight, and time under confinement. The normalized shear modulus reduction and material damping curves for MSW depend on waste composition and confining stress. Based on the results of this study and a review of literature, strain-dependent shear modulus reduction and material damping relationships are recommended for use in landfill design.
Shear banding and cross-anisotropic behavior observed in laboratory sand tests with stress rotation
Authors: Lade Poul V. , Nam Jungman , Hong Won Pyo
Published: March 2008

Shear banding in Santa Monica beach sand deposited by dry pluviation in hollow cylinder specimens is studied in 34 drained torsion shear tests with rotation of principal stress directions. The effect of the specimen height on the soil behavior was investigated by testing specimens with heights of 40 and 25 cm. Each test was conducted with the same, constant inside and outside confining pressure, σr, thus tying the value of b = (σ2– σ3)/(σ1– σ3) to the inclination, β, of the major principal stress. Shear bands can develop freely without significant restraint from the soft rubber membranes. Strain localization and shear banding were observed in the hollow cylinder specimens, and this created failure conditions in plane strain and in tests with higher b-values. The results clearly indicate the influence of the cross-anisotropic fabric on the stress–strain behavior, on the shear band inclination, and on the shape of the failure surface.
Phase initiale de régénération après feu des populations conifériennes subarctiques
Authors: Duchesne Sonia , Sirois Luc
Published: March 2008

The objective of this study was to investigate the first stage of post-fire regeneration of black spruce and jack pine in a black spruce woodland and a jack pine forest burned over in 1989 in the Radisson's region, in northern Quebec. Emphasis was given to determine the optimal microsites for black spruce and jack pine regeneration. Our results show that the burned over jack pine forest offers better substrates for seedling germination than the burned over black spruce one. A total of 139 seedlings were observed in the jack pine forest, whereas only 42 were recorded in the black spruce forest. In the jack pine forest, burned over humus was the preferred substrate for germination. Soil moisture content correlated with seed germination of both species. Soil temperatures at −5 cm and the soil surface influenced survival of black spruce seedlings in the jack pine forest
EXTENDING CHUA'S GLOBAL EQUIVALENCE THEOREM ON WOLFRAM'S NEW KIND OF SCIENCE
Authors: GUAN JUNBIAO , SHEN SHAOWEI , TANG CHANGBING , CHEN FANGYUE
Published: March 2008

We establish the relation between the extended (i.e. I = ∞) one-dimensional binary Cellular Automata (1D CA) and the bi-infinite symbolic sequences in symbolic dynamics. That is, the 256 local rules of 1D CA correspond to 256 local rule mappings in the symbolic space. By employing the two homeomorphisms T† and [Formula: see text] from [Chua et al., 2004] for finite I, we classify these 256 local rule mappings into the same 88 equivalence classes identified in [Chua et al., 2004] and [Chua, 2006]. Different mappings in the same equivalence class are mutually topologically conjugate.
MODEL VALIDATION OF SPATIOTEMPORAL SYSTEMS USING CORRELATION FUNCTION TESTS
Authors: PAN Y. , BILLINGS S. A.
Published: March 2008

The purpose of model validation is to test the goodness of fit of the identified model and to check whether the model is an appropriate representation of the underlying system. Model validation is a final and essential stage in most system identification procedures. Although model validation for nonlinear temporal systems has been extensively studied, model validation for spatiotemporal systems is still an open question. In this paper, correlation based methods, which have been successfully applied in nonlinear temporal systems are extended and enhanced to validate models of spatiotemporal systems. New nonlinear correlation functions are constructed based on the inputs, one-step-ahead predicted outputs and the residuals to test the dependency between the residuals and inputs/outputs. Examples are included to demonstrate the application of the tests.
COMPUTER ASSISTED VERIFICATION OF CHAOS IN THREE-NEURON CELLULAR NEURAL NETWORKS
Authors: YUAN QUAN , YANG XIAO-SONG
Published: March 2008

In this paper, we study a new class of simple three-neuron chaotic cellular neural networks with very simple connection matrices. To study the chaotic behavior in these cellular neural networks demonstrated in numerical studies, we resort to Poincaré section and Poincaré map technique and present a rigorous verification of the existence of horseshoe chaos using topological horseshoe theory and the estimate of topological entropy in derived Poincaré maps.
ENERGY-AWARE STAGE ILLUMINATION
Authors: EISENBRAND FRIEDRICH , FUNKE STEFAN , KARRENBAUER ANDREAS , MATIJEVIC DOMAGOJ
Published: March 2008

Consider the following illumination problem: given a stage represented by a line segment L and a set of light sources represented by a set of points S in the plane, assign powers to the light sources such that every point on the stage receives a sufficient amount – e.g. one unit – of light while minimizing the overall power consumption. Under the assumption that the amount of light arriving from a fixed light source decreases rapidly with the distance from the light source, this becomes an interesting optimization problem.

We propose to reconsider the classical illumination problems as known from computational geometry literature under this light attenuation model. This paper examines the simple problem introduced above and presents different solutions, based on convex optimization, discretization and linear programming, as well as a purely combinatorial approximation algorithm. Some experimental results are also provided.
COLLABORATIVE FILTERING FOR MULTI-CLASS DATA USING BAYESIAN NETWORKS
Authors: SU XIAOYUAN , KHOSHGOFTAAR TAGHI M.
Published: March 2008

As one of the most successful recommender systems, collaborative filtering (CF) algorithms are required to deal with high sparsity and high requirement of scalability amongst other challenges. Bayesian networks (BNs), one of the most frequently used classifiers, can be used for CF tasks. Previous works on applying BNs to CF tasks were mainly focused on binary-class data, and used simple or basic Bayesian classifiers.1,2 In this work, we apply advanced BNs models to CF tasks instead of simple ones, and work on real-world multi-class CF data instead of synthetic binary-class data. Empirical results show that with their ability to deal with incomplete data, the extended logistic regression on tree augmented naïve Bayes (TAN-ELR)3 CF model consistently performs better than the traditional Pearson correlation-based CF algorithm for the rating data that have few items or high missing rates. In addition, the ELR-optimized BNs CF models are robust in terms of the ability to make predictions, while the robustness of the Pearson correlation-based CF algorithm degrades as the sparseness of the data increases.
ADAPTIVE APPEARANCE BASED FACE RECOGNITION
Authors: LI QI , YE JIEPING , LI MIN , KAMBHAMETTU CHANDRA
Published: March 2008

In this paper, we present an adaptive appearance based face recognition framework that combines the efficiency of global approaches and the robustness of local approaches together. The framework uses a novel eye locator to select an appropriate scheme for appearance based recognition. The eye locator first locates eye candidates via a new strength assignment, determined by the dissimilarity between the local appearance of an image point and the appearance of its neighboring points. Then the eye locator applies a simple but flexible model (half-circle snake) to the local context of the eye candidates in order to either refine the location of an eye candidate or discard non-eye candidates. We show the performance of our framework by testing on challenging face datasets containing extreme expressions, severe occlusions, and varied lighting conditions.
INCREMENTAL FILTERING ALGORITHMS FOR PRECEDENCE AND DEPENDENCY CONSTRAINTS
Authors: BARTÁK ROMAN , ČEPEK ONDŘEJ
Published: March 2008

Precedence constraints specify that an activity must finish before another activity starts and hence such constraints play a crucial role in planning and scheduling problems. Many real-life problems also include dependency constraints expressing logical relations between the activities – for example, an activity requires presence of another activity in the plan. For such problems a typical objective is a maximization of the number of activities satisfying the precedence and dependency constraints. In the paper we propose new incremental filtering rules integrating propagation through both precedence and dependency constraints. We also propose a new filtering rule using the information about the requested number of activities in the plan. We demonstrate efficiency of the proposed rules on log-based reconciliation problems and min-cutset problems.
Toward a Control Theory Analysis of Aging
Authors: Murphy Michael P. , Partridge Linda
Published: March 2008

Aging is due to the accumulation of damage over time that affects the function and survival of the organism; however, it has proven difficult to infer the relative importance of the many processes that contribute to aging. To address this, here we outline an approach that may prove useful in analyzing aging. In this approach, the function of the organism is described as a set of interacting physiological systems. Degradation of their outputs leads to functional decline and death as a result of aging. In turn, degradation of the system outputs is attributable to changes at the next hierarchical level down, the cell, through changes in cell number or function, which are in turn a consequence of the metabolic history of the cell. Within this framework, we then adapt the methods of metabolic control analysis (MCA) to determine which modifications are important for aging. This combination of a hierarchical framework and the methodologies of MCA may prove useful both for thinking about aging and for analyzing it experimentally.
Mitochondrial Disorders in the Nervous System
Authors: DiMauro Salvatore , Schon Eric A.
Published: March 2008

Mitochondrial diseases (encephalomyopathies) have traditionally been ascribed to defects of the respiratory chain, which has helped researchers explain their genetic and clinical complexity. However, other mitochondrial functions are greatly important for the nervous system, including protein importation, organellar dynamics, and programmed cell death. Defects in genes controlling these functions are attracting increasing attention as causes not only of neurological (and psychiatric) diseases but also of age-related neurodegenerative disorders. After discussing some pathogenic conundrums regarding the neurological manifestations of the respiratory chain defects, we review altered mitochondrial dynamics in the etiology of specific neurological diseases and in the physiopathology of more common neurodegenerative disorders.
The Social Processes of Civil War: The Wartime Transformation of Social Networks
Authors: Wood Elisabeth Jean
Published: March 2008

Little attention has been paid to the social processes of civil war—the transformation of social actors, structures, norms, and practices—that sometimes leave enduring legacies for the postwar period. In this article, I explore the changes wrought by six social processes: political mobilization, military socialization, polarization of social identities, militarization of local authority, transformation of gender roles, and fragmentation of the local political economy. Some of these social processes occur in peacetime, but war may radically change their pace, direction, or consequences, with perhaps irreversible effects. I trace the wide variation in these processes during the wars in four countries: Peru, El Salvador, Sri Lanka, and Sierra Leone. I analyze the effects of these processes as transformations in social networks. These processes reconfigure social networks in a variety of ways, creating new networks, dissolving some, and changing the structure of others.
The use of multiple tools for teaching medical biochemistry
Authors: Sé Alexandre B. , Passos Renato M. , Ono André H. , Hermes-Lima Marcelo
Published: March 2008

In this work, we describe the use of several strategies employing the philosophies of active learning and problem-based learning (PBL) that may be used to improve the teaching of metabolic biochemistry to medical and nutritional undergraduate students. The main activities are as follows: 1) a seminar/poster system in a mini-congress format (using topics of applied biochemistry); 2) a true/false applied biochemistry exam (written by peer tutors); 3) a 9-h exam on metabolism (based in real publications); 4) the Advanced Biochemistry course (directed to peer tutors, where students learn how to read and criticize real medical papers); 5) experiments about nutrition and metabolism, using students as volunteers, and about free radicals (real science for students); 6) the BioBio blog (taking advantage of the “web age,” this enhances out of class exchanges of information between the professor, students, and peer tutors); 7) student lectures on public health issues and metabolic disorders directed to the community and lay people; and 8) the BioBio quiz show. The main objective of these activities is to provide students with a more practical and interesting approach to biochemistry, such as the application of theoretical knowledge to real situations (diseases, experiments, media information, and scientific discoveries). In addition, we emphasize the importance of peer tutor activities for optimized learning of both students and peer tutors, the importance of a closer interaction between students and teaching staff, and the necessity to initiate students precociously in two broad fields of medical activity: “real” basic science and contact with the public (also helping students–future doctors and nutritionists–to be able to communicate with lay people). Most activities were evaluated by the students through written questionnaires and informal conversations, along various semesters, indicating good acceptance and approval of these methods. Good student scores in the biochemistry exams and seminars indicated that these activities are also working as valid educational tools.
IT-based activity in physiology education: an experience from a developing country
Authors: Kommalage Mahinda , Gunawardena Sampath
Published: March 2008

Information technology (IT)-based components are included as active learning activities in medical curricula that have been shown to be more effective than most passive learning activities. In developing countries, these activities are not popular compared with developed countries. In this study, an IT-based assignment was carried out in physiology for undergraduates in Sri Lanka. We assessed certain basic IT capabilities before the assignment and found that the capability of using MS Word, e-mail, and the internet was limited to 68.3%, 62.0%, and 49.2% of students, respectively, with 40.8% of students having some other IT capabilities. We found a considerable variation in IT capabilities among the students, which depended on IT learning at schools and the geographical locations where students came from. The main source of IT knowledge for students was an introductory IT course given in the medical school with the second source being private IT learning centers. Response to the IT-based assignment was very poor. The reasons for poor participation included a lack of time due to parallel subjects, poor IT knowledge, and poor IT resource availability. However, students were willing to have optional IT-based components and were aware that IT knowledge is important for medical students as well as doctors. This study shows the importance of improving IT knowledge in students and the need of improving IT resources in medical schools. With these improvements, physiology education can be enriched with more interactive IT-based learning activities, which help students to acquire knowledge more efficiently and effectively in developing countries like Sri Lanka.
ACCF/ASE/ACEP/AHA/ASNC/SCAI/SCCT/SCMR 2008 Appropriateness Criteria for Stress Echocardiography
Authors:   STRESS ECHOCARDIOGRAPHY WRITING GROUP, Douglas Pamela S. , Khandheria Bijoy , Stainback Raymond F. , Weissman Neil J. ,   TECHNICAL PANEL MEMBERS, Peterson Eric D. , Hendel Robert C. , Stainback Raymond F. , Blaivas Michael , Des Prez Roger D. , Gillam Linda D. , Golash Terry , Hiratzka Loren F. , Kussmaul William G. , Labovitz Arthur J. , Lindenfeld JoAnn , Masoudi Frederick A. , Mayo Paul H. , Porembka David , Spertus John A. , Wann L. Samuel , Wiegers Susan E. ,   ACCF APPROPRIATENESS CRITERIA TASK FORCE, Brindis Ralph G. , Douglas Pamela S. , Hendel Robert C. , Patel Manesh R. , Peterson Eric D. , Wolk Michael J. , Allen Joseph M.
Published: March 2008

The American College of Cardiology Foundation (ACCF) and the American Society of Echocardiography (ASE) together with key specialty and subspecialty societies, conducted an appropriateness review for stress echocardiography. The review assessed the risks and benefits of stress echocardiography for several indications or clinical scenarios and scored them on a scale of 1 to 9 (based upon methodology developed by the ACCF to assess imaging appropriateness). The upper range (7 to 9) implies that the test is generally acceptable and is a reasonable approach, and the lower range (1 to 3) implies that the test is generally not acceptable and is not a reasonable approach. The midrange (4 to 6) indicates a clinical scenario for which the indication for a stress echocardiogram is uncertain. The indications for this review were drawn from common applications or anticipated uses, as well as from current clinical practice guidelines. Use of stress echocardiography for risk assessment in patients with coronary artery disease (CAD) was viewed favorably, while routine repeat testing and general screening in certain clinical scenarios were viewed less favorably. It is anticipated that these results will have a significant impact on physician decision making and performance, reimbursement policy, and will help guide future research.
Reversal of Global Apoptosis and Regional Stress Kinase Activation by Cardiac Resynchronization
Authors: Chakir Khalid , Daya Samantapudi K. , Tunin Richard S. , Helm Robert H. , Byrne Melissa J. , Dimaano Veronica L. , Lardo Albert C. , Abraham Theodore P. , Tomaselli Gordon F. , Kass David A.
Published: March 2008

Background—

Cardiac dyssynchrony in the failing heart worsens global function and efficiency and generates regional loading disparities that may exacerbate stress-response molecular signaling and worsen cell survival. We hypothesized that cardiac resynchronization (CRT) from biventricular stimulation reverses such molecular abnormalities at the regional and global levels.

Methods and Results—

Adult dogs (n=27) underwent left bundle-branch radiofrequency ablation, prolonging the QRS by 100%. Dogs were first subjected to 3 weeks of atrial tachypacing (200 bpm) to induce dyssynchronous heart failure (DHF) and then randomized to either 3 weeks of additional atrial tachypacing (DHF) or biventricular tachypacing (CRT). At 6 weeks, ejection fraction improved in CRT (2.8±1.8%) compared with DHF (−4.4±2.7;
P
=0.02 versus CRT) dogs, although both groups remained in failure with similarly elevated diastolic pressures and reduced dP/dtmax. In DHF, mitogen-activated kinase p38 and calcium-calmodulin–dependent kinase were disproportionally expressed/activated (50% to 150%), and tumor necrosis factor-α increased in the late-contracting (higher-stress) lateral versus septal wall. These disparities were absent with CRT. Apoptosis assessed by terminal deoxynucleotide transferase-mediated dUTP nick-end labeling staining, caspase-3 activity, and nuclear poly ADP-ribose polymerase cleavage was less in CRT than DHF hearts and was accompanied by increased Akt phosphorylation/activity. Bcl-2 and BAD protein diminished with DHF but were restored by CRT, accompanied by marked BAD phosphorylation, enhanced BAD–14-3-3 interaction, and reduced phosphatase PP1α, consistent with antiapoptotic effects. Other Akt-coupled modulators of apoptosis (FOXO-3α and GSK3β) were more phosphorylated in DHF than CRT and thus less involved.

Conclusions—

CRT reverses regional and global molecular remodeling, generating more homogeneous activation of stress kinases and reducing apoptosis. Such changes are important benefits from CRT that likely improve cardiac performance and outcome.
Deletion of
Ptpn11
(Shp2) in Cardiomyocytes Causes Dilated Cardiomyopathy via Effects on the Extracellular Signal–Regulated Kinase/Mitogen-Activated Protein Kinase and RhoA Signaling Pathways
Authors: Kontaridis Maria I. , Yang Wentian , Bence Kendra K. , Cullen Darragh , Wang Bo , Bodyak Natalya , Ke Qingen , Hinek Aleksander , Kang Peter M. , Liao Ronglih , Neel Benjamin G.
Published: March 2008

Background—

Heart failure is the leading cause of death in the United States. By delineating the pathways that regulate cardiomyocyte function, we can better understand the pathogenesis of cardiac disease. Many cardiomyocyte signaling pathways activate protein tyrosine kinases. However, the role of specific protein tyrosine phosphatases (PTPs) in these pathways is unknown.

Methods and Results—

Here, we show that mice with muscle-specific deletion of
Ptpn11
, the gene encoding the SH2 domain–containing PTP Shp2, rapidly develop a compensated dilated cardiomyopathy without an intervening hypertrophic phase, with signs of cardiac dysfunction appearing by the second postnatal month. Shp2-deficient primary cardiomyocytes are defective in extracellular signal–regulated kinase/mitogen-activated protein kinase (Erk/MAPK) activation in response to a variety of soluble agonists and pressure overload but show hyperactivation of the RhoA signaling pathway. Treatment of primary cardiomyocytes with Erk1/2- and RhoA pathway–specific inhibitors suggests that both abnormal Erk/MAPK and RhoA activities contribute to the dilated phenotype of Shp2-deficient hearts.

Conclusions—

Our results identify Shp2 as the first PTP with a critical role in adult cardiac function, indicate that in the absence of Shp2 cardiac hypertrophy does not occur in response to pressure overload, and demonstrate that the cardioprotective role of Shp2 is mediated via control of both the Erk/MAPK and RhoA signaling pathways.
Association Between Thrombotic Microangiopathy and Reduced ADAMTS13 Activity in Malignant Hypertension
Authors: van den Born Bert-Jan H. , van der Hoeven Niels V. , Groot Evelyn , Lenting Peter J. , Meijers Joost C.M. , Levi Marcel , van Montfrans Gert A.
Published: March 2008

The thrombotic microangiopathy observed in malignant hypertension is similar to that of thrombotic thrombocytopenic purpura, which is associated with a deficiency of ADAMTS13, a von Willebrand factor (VWF)–cleaving protease that cleaves large prothrombogenic multimers. We hypothesized that ADAMTS13 is deficient in malignant hypertension and that the severity of thrombotic microangiopathy is associated with decreased ADAMTS13 activity. We included 20 patients with malignant and 20 patients with severe hypertension, and 20 matched normotensive individuals served as control subjects. VWF, active VWF, and free hemoglobin were assessed to explore predictors of ADAMTS13 activity. Patients with malignant hypertension had lower ADAMTS13 activity (80%; interquartile range: 53% to 130%) compared with control subjects (99% interquartile range: 82% to 129%;
P
<0.01) but not compared with patients with severe hypertension (
P
=0.14). ADAMTS13 activity negatively correlated with lactic dehydrogenase levels after logarithmic transformation (
r
=−0.65;
P
<0.001) and was associated with platelet count (
r
=0.34;
P
=0.04) and the presence of schistocytes (
r
=−0.37;
P
=0.02). Apart from the association with thrombotic microangiopathy, ADAMTS13 was inversely associated with creatinine (
r
=−0.42;
P
=0.008). Increasing levels of VWF were associated with a decrease in ADAMTS13 activity (
r
=−0.34;
P
=0.03). There was no significant association between ADAMTS13 activity and other parameters, including blood pressure. In conclusion, ADAMTS13 is decreased in malignant hypertension and associated with the severity of thrombotic microangiopathy, likely because of the release of VWF after endothelium stimulation. A severe deficiency could not be demonstrated. More studies are needed to identify the role of ADAMTS13 in the thrombotic microangiopathy and ischemic complications of malignant hypertension.
Nighttime Blood Pressure and Nocturnal Dipping Are Associated With Daytime Urinary Sodium Excretion in African Subjects
Authors: Bankir Lise , Bochud Murielle , Maillard Marc , Bovet Pascal , Gabriel Anne , Burnier Michel
Published: March 2008

Blood pressure (BP) follows a circadian rhythm, with 10% to 15% lower values during nighttime than during daytime. The absence of a nocturnal BP decrease (dipping) is associated with target organ damage, but the determinants of dipping are poorly understood. We assessed whether the nighttime BP and the dipping are associated with the circadian pattern of sodium excretion. Ambulatory BP and daytime and nighttime urinary electrolyte excretion were measured simultaneously in 325 individuals of African descent from 73 families. When divided into sex-specific tertiles of day:night ratios of urinary sodium excretion rate, subjects in tertile 1 (with the lowest ratio) were 6.5 years older and had a 9.8-mm Hg higher nighttime systolic BP (SBP) and a 23% lower SBP dipping (expressed in percentage of day value) compared with subjects in tertile 3 (
P
for trend <0.01). After adjustment for age, the SBP difference across tertiles decreased to 5.4 mm Hg (
P
=0.002), and the SBP dipping difference decreased to 17% (
P
=0.05). A similar trend across tertiles was found with diastolic BP. In multivariate analyses, daytime urinary sodium and potassium concentrations were independently associated with nighttime SBP and SBP dipping (
P
<0.05 for each). These data, based on a large number of subjects, suggest that the capacity to excrete sodium during daytime is a significant determinant of nocturnal BP and dipping. This observation may help us to understand the pathophysiology and clinical consequences of nighttime BP and to develop therapeutic strategies to normalize the dipping profile in hypertensive patients.
Metabolic Photofragmentation Kinetics for a Minimal Protocell: Rate-Limiting Factors, Efficiency, and Implications for Evolution
Authors: Knutson Chad , Benkö Gil , Rocheleau Tristan , Mouffouk Fouzi , Maselko Jerzy , Chen Liaohai , Shreve Andrew P. , Rasmussen Steen
Published: March 2008

A key requirement of an autonomous self-replicating molecular machine, a protocell, is the ability to digest resources and turn them into building blocks. Thus a protocell needs a set of metabolic processes fueled by external free energy in the form of available chemical redox potential or light. We introduce and investigate a minimal photodriven metabolic system, which is based on photofragmentation of resource molecules catalyzed by genetic molecules. We represent and analyze the full metabolic set of reaction-kinetic equations and, through a set of approximations, simplify the reaction kinetics so that analytical expressions can be obtained for the building block production. The analytical approximations are compared with the full equation set and with corresponding experimental results to the extent they are available. It should be noted, however, that the proposed metabolic system has not been experimentally implemented, so this investigation is conducted to obtain a deeper understanding of its dynamics and perhaps to anticipate its limitations. We demonstrate that this type of minimal photodriven metabolic scheme is typically rate-limited by the front-end photoexcitation process, while its yield is determined by the genetic catalysis. We further predict that gene-catalyzed metabolic reactions can undergo evolutionary selection only for certain combinations of the involved reaction rates due to their intricate interactions. We finally discuss how the expected range of metabolic rates likely affects other key protocellular processes such as container growth and division as well as gene replication.
Joint Development in the East China Sea: Not an Easier Challenge than Delimitation
Authors: Jianjun Gao
Published: March 2008

As a form of provisional arrangement pending delimitation, the delineation of a joint development zone is significantly influenced by the maritime delimitation claims of the states concerned. In this sense, joint development is by no means an easier challenge to be tackled than delimitation. Because China has opted out of the compulsory procedures entailing binding decisions contained in the Law of the Sea Convention for delimitation issues, the only effective recourse available is to resort to negotiations. This means that unless China and Japan are ready to make concessions in their negotiations, no agreement can be reached, either for delimitation or for joint development.
Access to International Justice: A Review of the Trust Funds Available for Law of the Sea-Related Disputes
Authors: Claypoole Charles
Published: March 2008

The International Court of Justice, the Permanent Court of Arbitration and the International Tribunal for the Law of the Sea all have trust funds to assist States with limited financial resources to defray the costs of litigation. This article reviews these funds, in particular their conditions for eligibility and apparent success (in attracting contributions and requests for financial assistance). The author further considers the argument that developing States have been denied access to international justice for reasons of cost. Even though recent trends would indicate that this is not the case, there are nevertheless a large number of small States with very limited financial resources facing potentially complex Law of the Sea-related disputes for which these trust funds will be instrumental in facilitating international litigation. For this reason alone, it is important that if these trust funds are to be maintained grants made from them should realistically reflect the costs likely to be incurred in international legal proceedings.
Australia's Response to Illegal Foreign Fishing: A Case of winning the Battle but losing the Law?
Authors: Baird Rachel
Published: March 2008

The right of prompt release has been interpreted by the International Tribunal for the Law of the Sea as a safeguard, balancing the right of the coastal State to detain and deal with arrested fishing vessels and crew on the one hand, with the interests of the flag State to secure the release of detained vessels on the other. As the incidence of illegal fishing within national fishing zones has increased in the past decade, many coastal States, such as Australia, have implemented increasingly harsh penalties aimed at deterring the fishers. One such measure involves the operation of an automatic forfeiture regime whereby the detained vessel, gear and catch are forfeited to the Commonwealth. This regime operates in the absence of any judgement on the merits. This paper examines the details of the Australian legislation in addition to recent case law and concludes that the operation of the automatic forfeiture regime has the potential to upset the balance established in Article 73 of the 1982 United Nations Convention on the Law of the Sea.
The Orientation of JESHO's Orient and the Problem of 'Orientalism': Some Reflections on the Occasion of JESHO's Fiftieth Anniversary
Authors: Zurndorfer Harriet
Published: March 2008

This essay traces the fifty-year history of JESHO from its initiation by the Dutch economic historian N.W. Posthumus to the present. It appraises what values and assumptions propelled the Journal's first editors to utilize the expression 'Orient' in the publication's title, and how they coped with the changing vicissitudes of historical writing about 'the Rest' from the 1960s onward, including the impact of 'area studies' in North America. Finally, it gives a brief overview of the 'highs and lows' of JESHO's history, and how the most recent editors have readdressed the Journal's original mission to meet the demands of both exacting source-orientated original research and the writing of global history. JESHO a été fondé il y a cinquante ans par l'historien économique néerlandais N.W. Posthumus. Cette contribution en trace l'histoire depuis le début jusqu'jusqu'à aujourd'hui en évaluant quelques thèmes historiographiques, tels que les valeurs et hypothèses qui ont amené les premiers éditeurs à inclure le terme 'l'Orient' dans le titre de la revue, la façon dont ils s'en s'ont tirés en face des vicissitudes des écrits historiques concernant 'le reste du monde' depuis les années soixante, y compris l'effet de la recherche sur les aires régionales dans l'Amérique du Nord. Pour finir nous toucherons brièvement aux qualités et faiblesses de ces cinquante années, et à la manière dont les éditeurs de nos jours s'acquittent de la vocation des premiers temps de JESHO qui exige que la recherche soit innovatrice ainsi qu'orientée vers les sources primaires difficiles à pénétrer et tienne compte de l'histoire mondiale.
Characterization of Implantation Induced Defects in Si-Implanted SiO2 Film
Authors: Hao Xiaopeng , Zhou Chunlan , Yu Runsheng , Wang Baoyi , Wei Long
Published: March 2008

Si-implanted thermal SiO2 layers and their annealing behaviour were investigated. In the results of variable-energy positron annihilation spectroscopy, the defects caused by ion implantation are manifested as a particularly low S parameter in the Si ion implantation
region of the SiO2 layer. Compared with Fourier transform infrared measurements, it suggests that the decrease of the line shape S parameter after implantation is related to the compaction of implanted layers induced by the breaking of the SiO2 network structure.
The presence of blue band emission (430–470 nm) in the implanted SiO2 layer is associated with neutral oxygen vacancy. An increase of the S parameter in the implanted layers is observed after annealing at different temperatures, but it is impossible completely recover
the pre-implantation condition after a thermal treatment.
One-Step Synthesis and Luminescent Properties of Nanocrystalline YVO4:Eu3+ Powders
Authors: Kong Deyan , Wang Zhenling , Lin Cuikun , Yang Piaoping , Quan Zewei , Lin Jun
Published: March 2008

In this paper, nanocrystalline YVO4:Eu3+ powders have been successfully synthesized via high-temperature solution-phase synthesis process. The nanocrystalline YVO4:Eu3+ particles were characterized by X-ray diffraction (XRD), transmission
electron microscopy (TEM), UV/Vis absorption spectra and luminescence spectra, luminescence decay curve and Fourier transform infrared (FT-IR), X-ray photoelectron spectra (XPS) respectively. The as-prepared nanocrystalline YVO4:Eu3+ particles are well crystallized with
ellipsoidal morphology. The emission of YVO4:Eu3+ particles show emission originating from the 5D0 level, with 5D0–7F2 at 616 nm as the most prominent group. The excitation spectrumfits basically
with the absorption spectrumfromthe vanadate ions. FT-IR and XPS spectra indicate that the surface ligands of nanocrystalline particles were oleic acid and oleylamine. The lifetime for the luminescence of Eu3+ in the as-prepared YVO4:Eu3+ samples are shorter
than that of the bulk material due to the absorption of organic ligands on the nanoparticle surface.
A Refined Calibration Procedure of Two-Channel Sun Photometers to Measure Atmospheric Precipitable Water at Various Antarctic Sites
Authors: Tomasi Claudio , Petkov Boyan , Benedetti Elena , Valenziano Luca , Lupi Angelo , Vitale Vito , Bonafé Ubaldo
Published: March 2008

Two-channel sun photometers can be easily employed at Antarctic sites, where harsh environmental conditions prevail, to carry out measurements of precipitable water W. In the very dry air conditions observed in the Antarctic atmosphere, water vapor does not produce strong absorption features along the sun path. Therefore, these instruments need to be calibrated using analytical forms different from the square root regime, which can be determined by simulating the output voltages measured at Antarctic sites, for the spectral near-IR curves of extraterrestrial solar irradiance, instrumental responsivity parameters, and atmospheric transmittance, relative to various measurement periods. For this purpose, average models of the Antarctic atmosphere from the ground level up to the 30-km altitude were considered for different solar zenith angles and relative humidity conditions. The ratios between the output voltages simulated in the band and window channels were plotted as a function of total water vapor content Cw, for each site and each period, to define the best-fit calibration curves, which were subsequently normalized to the field measurements to take into account the aging effects on the filter transmission characteristics. Each of the five calibration curves was found to present a slope coefficient decreasing gradually with Cw from values higher than 0.8 to about 0.6. Using these curves, measurements of W were obtained, which differ appreciably at both sea level and high-altitude sites from those given by the square root calibration curves, avoiding large overestimation errors of 10%–40% at the high-altitude sites and underestimation errors of 5%–15% at the sea level site.
Performance of the Precipitation Occurrence Sensor System as a Precipitation Gauge
Authors: Sheppard B. E. , Joe P. I.
Published: March 2008

The Precipitation Occurrence Sensor System (POSS) is a small X-band Doppler radar originally developed by the Meteorological Service of Canada for reporting the occurrence, type, and intensity of precipitation from Automated Weather Observing Stations. This study evaluates POSS as a gauge for measuring amounts of both liquid and solid precipitation. Different precipitation rate estimation algorithms are described. The effect of different solid precipitation types on the Doppler velocity spectrum is discussed. Lacking any accepted reference for high temporal resolution rates, the POSS precipitation rate measurements are integrated over time periods ranging from 6 h to one day and validated against international and Canadian reference gauges. Data from a wide range of sites across Canada and for periods of several years are used. The statistical performance of POSS is described in terms of the distribution of ratios of POSS to reference gauge amounts (catch ratios). In liquid precipitation the median of the catch ratio distribution is 82% and the interquartile range was between −12% and 19% about the median. In solid precipitation the median is 90% and the interquartile range is between −17% and 24% about the median. The underestimation in both liquid and solid precipitation is shown to be a function of precipitation rate and phase. The effects of radome wetting, raindrop splashing, wind, and the radar “brightband” effect on the estimation of precipitation rates are discussed.
A Collector for Fog Water and Interstitial Aerosol
Authors: Klemm Otto , Wrzesinsky Thomas , Gerchau Jörg , Griessbaum Frank
Published: March 2008

An active heatable cloud water collector for ground sampling is presented. The collector can be operated unattended for approximately one week, even in harsh winter conditions. The collection strands are Teflon tubes. A preset cycle of 15-min sampling followed by 250 s of mild heating using wires inserted into the tubes is used. The lower cutoff diameter for fog droplets is 7.3 μm, and its overall collection efficiency is 79% for the liquid water content of fogs at the experimental site in central Europe. It performed reliably during a 2-yr experiment. The collected fog water interacts exclusively with inert materials such as Teflon and Perspex so the collector is well suited for trace analyses of fog water. The collector can be upgraded with an interstitial aerosol collection unit, at the expense of unattended operation. The lower cutoff diameter of the fog water collection strands is 8.1 μm when the interstitial aerosol module is installed. The module efficiently collects particles with diameters <3.5 μm. For these particles, size-segregated samples in four size classes at diameters down to 0.06 μm are collected with a Berner-type impactor. The collector was successfully employed in a mountainous region of central Europe. Over 400 samples were collected within 2 yr. With the collection unit for interstitial aerosol added, 31 samples were collected in a 2-month period.
First Passage Time Analysis on Climate Indices
Authors: Chu Peter C.
Published: March 2008

Climate variability is simply represented by teleconnection patterns such as the Arctic Oscillation (AO), Antarctic Oscillation (AAO), North Atlantic Oscillation (NAO), Pacific–North American pattern (PNA), and Southern Oscillation (SO) with associated indices. Two approaches can be used to predict the indices: forward and backward methods. The forward method is commonly used to predict the index fluctuation ρ at time t with a given temporal increment τ. Using this method, it was found that the index (such as for NAO) has the Brownian fluctuations. On the basis of the first passage time (FPT) concept, the backward method is introduced in this study to predict the typical time span (τ) needed to generate a fluctuation in the index of a given increment ρ. After the five monthly indices (AO, AAO, NAO, PNA, and SO) run through the past history, the FPT density functions are obtained. FPT presents a new way to detect the temporal variability of the climate indices. The basic features for the index prediction are also discussed.
Infrared Techniques for Measuring Ocean Surface Processes
Authors: Veron Fabrice , Melville W. Kendall , Lenain Luc
Published: March 2008

Ocean surface processes, and air–sea interaction in general, have recently received increased attention because it is now accepted that small-scale surface phenomena can play a crucial role in the air–sea fluxes of heat, mass, and momentum, with important implications for weather and climate studies. Yet, despite good progress in recent years, the air–sea interface and the adjacent atmospheric and marine boundary layers have proven to be difficult to measure in all but the most benign conditions. This has led to the need for novel measurement techniques to quantify processes of air–sea interaction. Here the authors present infrared techniques aimed at simultaneously studying multiple aspects of the air–sea interface and air–sea fluxes. The instrumentation was tested and deployed during several field experiments from Research Platform (R/P) FLIP and Scripps pier. It is shown that these techniques permit the detailed study of the ocean surface temperature and velocity fields. In particular, it is shown that cross-correlation techniques typically used in particle image velocimetry can be used to infer the ocean surface velocity field from passive infrared temperature images. In addition, when conditions make cross-correlation techniques less effective, an active infrared marking and tracking technique [which will be called thermal marker velocimetry (TMV)] can be successfully used to measure the surface velocity and its spatial and temporal derivatives. The thermal marker velocimetry technique also provides estimates of the heat transfer velocity and surface renewal frequencies. Finally, infrared altimetry is used to complement the temperature and kinematic data obtained from passive imagery and active marking. The data obtained during the testing and deployment of this instrumentation provide a novel description of the kinematics of the surface of the ocean.
Extracting Reynolds Stresses from Acoustic Doppler Current Profiler Measurements in Wave-Dominated Environments
Authors: Rosman Johanna H. , Hench James L. , Koseff Jeffrey R. , Monismith Stephen G.
Published: March 2008

Surface waves introduce velocity correlations that bias and often dominate Reynolds stress estimates made using the traditional variance method for acoustic Doppler current profilers (ADCPs). This analysis shows that the wave bias is the sum of a real wave stress and an error due to instrument tilt, both of which have a large uncertainty. Three alternative extensions to the variance method for calculating Reynolds stress profiles from ADCP measurements in wavy conditions are analyzed. The previously proposed variance fitting method (Variance Fit) is evaluated and two more general methods that use along- and between-beam velocity differencing with adaptive filtering (Vertical AF and Horizontal AF) are derived. The three methods are tested on datasets containing long-period monochromatic swell (Moorea, French Polynesia) and shorter-period mixed swell (Santa Barbara, California). The Variance Fit method leaves a residual wave bias in beam velocity variances, especially for intermediate waves, but gives physically reasonable Reynolds stress estimates because most of the residual wave bias cancels when the variance method is applied. The new Vertical AF method does not produce inherent wave bias in beam velocity variances, but yields comparable Reynolds stresses to the Variance Fit method. The Horizontal AF method performs poorly for all but monochromatic waves. Error remaining after one of the above methods is applied can be attributed to residual wave error, correlation of turbulence between points chosen for differencing, or correlation between waves and turbulence. A simple procedure is provided for determining the minimum bin separation that can be used.