bluuebunny/crossref_metadata_2025 huggingface dataset:
The Role of Aerosols in the Evolution of Tropical North Atlantic Ocean Temperature Anomalies
Authors: Evan Amato T. , Vimont Daniel J. , Heidinger Andrew K. , Kossin James P. , Bennartz Ralf
Published: March 2009

Dust in the Wind

The temperature of North Atlantic surface waters has a major effect on climate in a variety of ways, not least because its heat content helps to control hurricane formation and strength. The North Atlantic surface has warmed considerably in recent decades, a trend generally associated with global or regional air temperature increases, or with changes in ocean circulation.

Evan
et al.

(p.
778
, published online 26 March) use nearly 30 years of satellite data to examine another source of ocean temperature variability, the radiative effects of atmospheric aerosols. Low frequency changes in local tropical North Atlantic surface temperatures seem mostly to be caused by variability in mineral and stratospheric aerosol abundances. Thus, to provide more accurate projections of these temperatures, general circulation models will need to account for long-term changes in dust loadings.
GRÖBNER–SHIRSHOV BASES FOR FREE INVERSE SEMIGROUPS
Authors: BOKUT L. A. , CHEN YUQUN , ZHAO XIANGUI
Published: March 2009

A new construction for free inverse semigroups was obtained by Poliakova and Schein in 2005. Based on their result, we find Gröbner–Shirshov bases for free inverse semigroups with respect to the deg-lex order of words. In particular, we give the (unique and shortest) normal forms in the classes of equivalent words of a free inverse semigroup together with the Gröbner–Shirshov algorithm to transform any word to its normal form.
UNITARY UNITS OF THE GROUP ALGEBRA 𝔽2kQ8
Authors: CREEDON LEO , GILDEA JOE
Published: March 2009

The structure of the unitary unit group of the group algebra 𝔽2kQ8 is described as a Hamiltonian group.
DYNAMIC PORTFOLIO SELECTION WITH UNCERTAINTY
Authors: YU MEI , INOUE HIROSHI , TAKAHASHI SATORU , SHI JIANMING
Published: March 2009

How to make a prompt decision for uncertainty investment is always a key problem in financial market. In this paper, we present a new dynamic portfolio selection strategy in stock market. The investor is assumed to seek an investment strategy that will maximize his/her final wealth and minimize the total risk. An analytically optimal strategy in closed form is obtained by solving a dynamic programming problem. Some applications are also presented to illustrate this model.
FACE RECOGNITION BY RING ROTATION INVARIANT TRANSFORM AND MANAGING IMAGE ROTATION AND SHIFTING PROBLEMS
Authors: SU CHING-LIANG
Published: March 2009

Generally, for face recognition, image shift and rotation problems must be addressed. The "ring rotation invariant transform" technique is used to transfer geometrical features of face image to other more salient ones; by which one can identify whether a sample or unknown image is the identical image. It also can solve image rotation problem. To deal with the image-shifting problem, this study uses one pixel inside a sample image to compare with the corresponding pixels in the unknown image to locate the closest matching point. In this study, three different kinds of extracted ring signals are generated, which are (1) ring-radius-31, (2) ring-radius-22, and (3) ring-radius-13. These signals are used to generate the rotation invariant magnitudes and several magnitudes are combined as one entity and, subsequently, saved inside one specific corresponding pixel in the BMP file. By this approach, one pixel will possess more geometrical-features of the face images; one entity in sample image is compared with entities inside the corresponding radius-6-cake area of the unknown image to locate the closest matching point.
MULTIRESOLUTION ANALYSIS AND HAAR WAVELETS ON THE PRODUCT OF HEISENBERG GROUP
Authors: XIE PEIZHU , HE JIANXUN
Published: March 2009

In this paper, the properties of multiresolution analysis on the product of Heisenberg group are investigated. Moreover, orthonormal Haar wavelet bases for L2(ℋn) are constructed.
GEOLOGIC EVIDENCE FOR THREE GREAT EARTHQUAKES IN THE PAST 3400 YEARS OFF MYANMAR
Authors: AUNG THAN TIN , SATAKE KENJI , OKAMURA YUKINOBU , SHISHIKURA MASANOBU , SWE WIN , SAW HLA , SWE TINT LWIN , TUN SOE THURA , AUNG THURA
Published: March 2009

Tectonic environments, recent stress and crustal strain observations, and historical descriptions of geomorphological changes and eyewitness accounts of the 1762 Bengal earthquake suggest that great earthquakes (M 8.0 or larger) can occur along the northward continuation of the 2004 Sumatra-Andaman earthquake. We describe marine terraces along the Rakhine coast of Myanmar as evidence for three great earthquakes in the past 3400 years. Radiocarbon dating of coral remains suggests that the oldest terrace emerged three times, during 1395–740 BC, AD 805–1220 and AD 1585–1810. We assign the youngest age to the 1762 earthquake, which reportedly raised parts of the Burmese coast by 3–7 m. These indicate that the great subduction-zone earthquakes have repeatedly occurred west off Myanmar with an average recurrence interval of about 1000–2000 years. The time since the last earthquake, ~ 250 years, is much shorter than the average interval, hence the chance of next earthquakes in the near future may be considered as low. However, the variability in both uplift amounts and recurrence intervals suggests the next great earthquake could happen sooner or later than would be expected from the average interval.
Low-amplitude pulses to the circulation through periodic acceleration induces endothelial-dependent vasodilatation
Authors: Uryash Arkady , Wu Heng , Bassuk Jorge , Kurlansky Paul , Sackner Marvin A. , Adams Jose A.
Published: March 2009

Low-amplitude pulses to the vasculature increase pulsatile shear stress to the endothelium. This activates endothelial nitric oxide (NO) synthase (eNOS) to promote NO release and endothelial-dependent vasodilatation. Descent of the dicrotic notch on the arterial pulse waveform and a-to- b ratio ( a/ b; where a is the height of the pulse amplitude and b is the height of the dicrotic notch above the end-diastolic level) reflects vasodilator (increased a/ b) and vasoconstrictor effects (decreased a/ b) due to NO level change. Periodic acceleration (pGz) (motion of the supine body head to foot on a platform) provides systemic additional pulsatile shear stress. The purpose of this study was to determine whether or not pGzapplied to rats produced endothelial-dependent vasodilatation and increased NO production, and whether the latter was regulated by the Akt/phosphatidylinositol 3-kinase (PI3K) pathway. Male rats were anesthetized and instrumented, and pGzwas applied. Sodium nitroprusside, NG-nitro-l-arginine methyl ester (l-NAME), and wortmannin (WM; to block Akt/PI3K pathway) were administered to compare changes in a/ b and mean aortic pressure. Descent of the dicrotic notch occurred within 2 s of initiating pGz. Dose-dependent increase of a/ b and decrease of mean aortic pressure took place with SNP. l-NAME produced a dose-dependent rise in mean aortic pressure and decrease of a/ b, which was blunted with pGz. In the presence of WM, pGzdid not decrease aortic pressure or increase a/ b. WM also abolished the pGzblunting effect on blood pressure and a/ b of l-NAME-treated animals. eNOS expression was increased in aortic tissue after pGz. This study indicates that addition of low-amplitude pulses to circulation through pGzproduces endothelial-dependent vasodilatation due to increased NO in rats, which is mediated via activation of eNOS, in part, by the Akt/PI3K pathway.
Congenital Diaphragmatic Hernia: Comparison of Animal Models and Relevance to the Human Situation
Authors: van Loenhout Rhiannon B. , Tibboel Dick , Post Martin , Keijzer Richard
Published: March 2009

Congenital diaphragmatic hernia (CDH) occurs in 1 in 3,000 newborns. Mortality and morbidity are due to the amount of pulmonary hypoplasia (PH), the response on artificial ventilation and the presence of therapy-resistant pulmonary hypertension. The pathogenesis and etiology of CDH and its associated anomalies are still largely unknown despite all research efforts over the past years. Several animal models have been proposed to study CDH. In this review we compare surgical, pharmacological and transgenic models, and discuss their strengths and limitations to study PH.
Analysis of Risk Factors for Catheter-Related Bacteremia in 2000 Permanent Dual Catheters for Hemodialysis
Authors: Lemaire Xavier , Morena Marion , Leray-Moragués Hélène , Henriet-Viprey Delphine , Chenine Leila , Defez-Fougeron Christine , Canaud Bernard
Published: March 2009

Background: Infection constitutes a leading cause of morbidity and mortality in hemodialysis (HD) patients. The type of vascular access is an important determinant of the risk of infection. Therefore, identification of risk factors leading to catheter-related bacteremia (CRB) is strongly required. The aim of this prospective large cohort study of HD patients using only catheters as vascular access was to isolate risk factors for CRB. Methods: 2,230 permanent silicone dual catheters implanted in 1,749 patients between November 1982 and November 2005 were studied. The following data were collected at the time of catheter implantation: presence of hypertension, diabetes mellitus, obesity, atherosclerosis, immunodepression, Wright-Khan index, site and side of catheter insertion, and history of bacteremia. Results: The site of catheter insertion was internal jugular (n = 2,133), subclavian (n = 79) and femoral (n = 17). Duration of catheter use was as follows: 30–90 days (n = 1,607) and >90 days (n = 1,054); 226 episodes of bacteremia occurred in 197 catheters. Microorganisms responsible were mainly Staphylococcus aureus, coagulase-negative staphylococci, Enterobacter spp. and Pseudomonas aeruginosa. The overall incidence of bacteremic episodes was 0.514/1,000 catheter days. Hypertension, atherosclerosis, diabetes mellitus, site of catheter implantation, duration of catheter use, Wright-Khan comorbidity index and previous history of CRB were significant risk factors associated with bacteremia in univariate analysis. Multivariate analysis revealed that a previous history of a bacteremic episode (odds ratio, OR = 2.70, 95% confidence interval, CI = 1.56–4.68), diabetes mellitus (OR = 2.37, 95% CI = 1.65–3.39), duration of catheter use >90 days (OR = 1.85, 95% CI = 1.35–2.55) and hypertension (OR = 1.49, 95% CI = 1.08–2.04) were still significant factors associated with bacteremia. Conclusion: Reducing CRB is still a challenge for nephrologists to reduce patient morbidity and mortality. Our study could demonstrate that diabetes, previous history of CRB, site of catheter implantation and duration of catheter use were the most important risk factors for bacteremia. Therefore, to prevent CRB, particular attention should be paid to patients with diabetes and a previous history of bacteremia following strict hygienic and aseptic rules for catheter handling associated with the regular use of antiseptic lock solutions.
Pivotal Role of Lnk Adaptor Protein in Endothelial Progenitor Cell Biology for Vascular Regeneration
Authors: Kwon Sang-Mo , Suzuki Takahiro , Kawamoto Atsuhiko , Ii Masaaki , Eguchi Masamichi , Akimaru Hiroshi , Wada Mika , Matsumoto Tomoyuki , Masuda Haruchika , Nakagawa Yoshihiro , Nishimura Hiromi , Kawai Kenji , Takaki Satoshi , Asahara Takayuki
Published: March 2009

Despite the fact that endothelial progenitor cells (EPCs) are important for postnatal neovascularization, their origins, differentiation, and modulators are not clear. Here, we demonstrate that Lnk, a negative regulator of hematopoietic stem cell proliferation, controls endothelial commitment of c-kit
+
/Sca-1
+
/Lineage
−
(KSL) subpopulations of bone marrow cells. The results of EPC colony–forming assays reveal that small (primitive) EPC colony formation by CD34
−
KSLs and large (definitive) EPC colony formation by CD34
(dim)
KSLs are more robust in
lnk
−/−
mice. In hindlimb ischemia, perfusion recovery is augmented in
lnk
−/−
mice through enhanced proliferation and mobilization of EPCs via c-Kit/stem cell factor. We found that Lnk-deficient EPCs are more potent actors than resident cells in hindlimb perfusion recovery and ischemic neovascularization, mainly via the activity of bone marrow-EPCs. Similarly,
lnk
−/−
mice show augmented retinal neovascularization and astrocyte network maturation without an increase in indicators of pathogenic angiogenesis in an in vivo model of retinopathy. Taken together, our results provide strong evidence that Lnk regulates bone marrow-EPC kinetics in vascular regeneration. Selective targeting of Lnk may be a safe and effective strategy to augment therapeutic neovascularization by EPC transplantation.
Estimating Instantaneous Irregularity of Neuronal Firing
Authors: Shimokawa Takeaki , Shinomoto Shigeru
Published: March 2009

Cortical neurons in vivo had been regarded as Poisson spike generators that convey no information other than the rate of random firing. Recently, using a metric for analyzing local variation of interspike intervals, researchers have found that individual neurons express specific patterns in generating spikes, which may symbolically be termed regular, random, or bursty, rather invariantly in time. In order to study the dynamics of firing patterns in greater detail, we propose here a Bayesian method for estimating firing irregularity and the firing rate simultaneously for a given spike sequence, and we implement an algorithm that may render the empirical Bayesian estimation practicable for data comprising a large number of spikes. Application of this method to electrophysiological data revealed a subtle correlation between the degree of firing irregularity and the firing rate for individual neurons. Irregularity of firing did not deviate greatly around the low degree of dependence on the firing rate and remained practically unchanged for individual neurons in the cortical areas V1 and MT, whereas it fluctuated greatly in the lateral geniculate nucleus of the thalamus. This indicates the presence and absence of autocontrolling mechanisms for maintaining patterns of firing in the cortex and thalamus, respectively.
Damage Kinetics of Glass/Epoxy Composite Materials Under Dynamic Compression
Authors: Tarfaoui M. , Neme A. , Choukri S.
Published: March 2009

The strain rate sensitivity of glass fiber-reinforced polymer is studied by testing a single laminate configuration at strain rates of 200—2000 s-1. The compressive material properties are determined by testing the laminate systems with different orientations from low to high strain rates. Samples of cubic geometry are tested in in-plane direction for seven fiber orientations, 08, ±208, ±308, ±458, ±608, ±708, and 908. Preliminary compressive stress—strain vs. strain rates data obtained show that the dynamic material strength increases with increasing strain rates. The tests show a strong material sensitivity to dynamic loading and fiber direction. For in-plane tests, there is a transitional strain rate and a transitional fiber orientation in the trends, reflecting the dependencies on strain rate and fiber orientation observed in experiments. Damage investigations have revealed that the failure events differ and depend on composite sequence lay-ups.
Emerging Peripheral Receptor Targets for Deep-tissue Craniofacial Pain Therapies
Authors: Ambalavanar R. , Dessem D.
Published: March 2009

While effective therapies are available for some types of craniofacial pain, treatments for deep-tissue craniofacial pain such as temporomandibular disorders are less efficacious. Several ion channels and receptors which are prominent in craniofacial nociceptive mechanisms have been identified on trigeminal primary afferent neurons. Many of these receptors and channels exhibit unusual distributions compared with extracranial regions. For example, expression of the ATP receptor P2X3 is strongly implicated in nociception and is more abundant on trigeminal primary afferent neurons than analogous extracranial neurons, making them potentially productive targets specifically for craniofacial pain therapies. The initial part of this review therefore focuses on P2X3 as a potential therapeutic target to treat deep-tissue craniofacial pain. In the trigeminal ganglion, P2X3 receptors are often co-expressed with the nociceptive neuropeptides CGRP and SP. Therefore, we discuss the role of CGRP and SP in deep-tissue craniofacial pain and suggest that neuropeptide antagonists, which have shown promise for the treatment of migraine, may have wider therapeutic potential, including the treatment of deep-tissue craniofacial pain. P2X3, TRPV1, and ASIC3 are often co-expressed in trigeminal neurons, implying the formation of functional complexes that allow craniofacial nociceptive neurons to respond synergistically to altered ATP and pH in pain. Future therapeutics for craniofacial pain thus might be more efficacious if targeted at combinations of P2X3, CGRP, TRPV1, and ASIC3.
Fine-tuning of Bioactive Glass for Root Canal Disinfection
Authors: Waltimo T. , Mohn D. , Paqué F. , Brunner T.J. , Stark W.J. , Imfeld T. , Schätzle M. , Zehnder M.
Published: March 2009

An ideal preparation of 45S5 bioactive glass suspensions/slurries for root canal disinfection should combine high pH induction with capacity for continuing release of alkaline species. The hypothesis of this study was that more material per volume of bioactive glass slurry is obtained with a micrometric material (< 5 μm particle size) or a micrometric/ nanometric hybrid, rather than a solely nanometric counterpart. This should correlate with alkaline capacity and antimicrobial effectiveness. Slurries at the plastic limit were prepared with test and reference materials in physiological saline. Total mass and specific surface area of glass material per volume were determined. Continuous titration with hydrochloric acid was performed, and antimicrobial effectiveness was tested in extracted human premolars mono-infected with E. faecalis ATTC 29212 (N = 12 per material). While the nanometric slurry had a 12-fold higher specific surface area than the micrometric counterpart, the latter had a considerably higher alkaline capacity and disinfected significantly better (Fisher’s exact test, P < 0.05). The hybrid slurry behaved similarly to the micrometric preparation.
Proteoglycans and Mechanical Behavior of Condylar Cartilage
Authors: Lu X.L. , Mow V.C. , Guo X.E.
Published: March 2009

Mandibular condylar cartilage functions as the load-bearing, shock-absorbing, lubricating material in temporomandibular joints. Little is known about the precise nature of the biomechanical characteristics of this fibro-cartilaginous tissue. We hypothesized that the fixed charge density associated with proteoglycans that introduces an osmotic pressure inside condylar cartilage will significantly increase the tissue’s apparent stiffness. Micro-indentation creep tests were performed on porcine TMJ condylar cartilage at 5 different regions—anterior, posterior, medial, lateral, and central—in physiologic and hypertonic solutions. The intrinsic and apparent mechanical properties, including aggregate modulus, shear modulus, and permeability, were calculated by indentation test data and the biphasic theory. The apparent properties (with osmotic effect) were statistically higher than those of the intrinsic solid matrix (without osmotic effect). Regional variations in fixed charge density, permeability, and mechanical modulus were also calculated for condylar surface. The present results provide important quantitative data on the biomechanical properties of TMJ condylar cartilage.
Time Courses of Subcellular Signal Transduction and Cellular Apoptosis in Remote Viable Myocardium of Rat Left Ventricles Following Acute Myocardial Infarction: Role of Pharmacomodulation
Authors: Chua Sarah , Chang Li-Teh , Sun Cheuk-Kwan , Sheu Jiunn-Jye , Lee Fan-Yen , Youssef Ali A. , Yang Cheng-Hsu , Wu Chiung-Jen , Yip Hon-Kan
Published: March 2009

We tested hypothesis that acute myocardial infarction (AMI) induces cellular apoptosis and serial changes of protein kinase C epsilon (PKC-e) and p38 mitogen-activated protein kinase (p38 MAPK), and tested cardio-protective effect of losartan in this condition. The rats were assigned to group A (sacrificed on day 2), group B (sacrificed on day 5), and group C (sacrificed on day 14). Rats in each group were further randomized into the following groups: AMI (ligation of left coronary artery) without losartan (AMI-L0); AMI with losartan 20 mg/ kg/d (AMI-L1); and sham groups (L0 and L1). The PKC-e expression in membrane compartment was increased in AMI-L1 group than in other groups on day 5 and in AMI groups than in sham groups on day 14 (P < .01). Phosphorylated form of cytosolic p38 MAPK level was increased in AMI-L1 than in other groups on day 14 (P < .05). Furthermore, 14-day left ventricular ejection fraction was higher and cellular apoptosis was lower in AMI-L1 group than in AMI-L0 group (P < .0001).
Reduction of T cell–derived ghrelin enhances proinflammatory cytokine expression: implications for age-associated increases in inflammation
Authors: Dixit Vishwa D. , Yang Hyunwon , Cooper-Jenkins Anthony , Giri Banabihari B. , Patel Kalpesh , Taub Dennis D.
Published: March 2009

Ghrelin (Grln) is a peptide hormone that is predominantly produced in the stomach and stimulates appetite and induces growth hormone (GH) release. We have previously reported that ghrelin is also expressed in T cells and exerts prothymic and anti-inflammatory effects. However, the biologic relevance of T cell–derived ghrelin remains to be determined. Here, we report that acylated-bioactive ghrelin is expressed in human T cells and preferentially segregates within the lipid raft domains upon TCR ligation. The RNA interference (RNAi)–mediated down-regulation of ghrelin in primary human T cells activates IkB, and increases Th1 cytokines and IL-17 secretion. Ghrelin expression declines with increasing age in spleen and T cells and exogenous ghrelin administration in old mice reduces proinflammatory cytokines. These findings demonstrate that ghrelin functions in an autocrine and paracrine capacity to regulate proinflammatory cytokine expression in human and murine T cells and may contribute in regulating “inflamm-aging.”
Prostaglandin E2 enhances hematopoietic stem cell homing, survival, and proliferation
Authors: Hoggatt Jonathan , Singh Pratibha , Sampath Janardhan , Pelus Louis M.
Published: March 2009

Adult hematopoietic stem cells (HSCs) are routinely used to reconstitute hematopoiesis after myeloablation; however, transplantation efficacy and multilineage reconstitution can be limited by inadequate HSC number, or poor homing, engraftment, or self-renewal. Here we report that mouse and human HSCs express prostaglandin E2 (PGE2) receptors, and that short-term ex vivo exposure of HSCs to PGE2 enhances their homing, survival, and proliferation, resulting in increased long-term repopulating cell (LTRC) and competitive repopulating unit (CRU) frequency. HSCs pulsed with PGE2 are more competitive, as determined by head-to-head comparison in a competitive transplantation model. Enhanced HSC frequency and competitive advantage is stable and maintained upon serial transplantation, with full multilineage reconstitution. PGE2 increases HSC CXCR4 mRNA and surface expression, enhances their migration to SDF-1 in vitro and homing to bone marrow in vivo, and stimulates HSC entry into and progression through cell cycle. In addition, PGE2 enhances HSC survival, associated with an increase in Survivin mRNA and protein expression and reduction in intracellular active caspase-3. Our results define novel mechanisms of action whereby PGE2 enhances HSC function and supports a strategy to use PGE2 to facilitate hematopoietic transplantation.
Folding machineries displayed on a cation-exchanger for the concerted refolding of cysteine- or proline-rich proteins
Authors: Lee Dae-Hee , Kim Sung-Gun , Kweon Dae-Hyuk , Seo Jin-Ho
Published: March 2009

Background

Escherichia coli has been most widely used for the production of valuable recombinant proteins. However, over-production of heterologous proteins in E. coli frequently leads to their misfolding and aggregation yielding inclusion bodies. Previous attempts to refold the inclusion bodies into bioactive forms usually result in poor recovery and account for the major cost in industrial production of desired proteins from recombinant E. coli. Here, we describe the successful use of the immobilized folding machineries for in vitro refolding with the examples of high yield refolding of a ribonuclease A (RNase A) and cyclohexanone monooxygenase (CHMO).

Results

We have generated refolding-facilitating media immobilized with three folding machineries, mini-chaperone (a monomeric apical domain consisting of residues 191–345 of GroEL) and two foldases (DsbA and human peptidyl-prolyl cis-trans isomerase) by mimicking oxidative refolding chromatography. For efficient and simple purification and immobilization simultaneously, folding machineries were fused with the positively-charged consecutive 10-arginine tag at their C-terminal. The immobilized folding machineries were fully functional when assayed in a batch mode. When the refolding-facilitating matrices were applied to the refolding of denatured and reduced RNase A and CHMO, both of which contain many cysteine and proline residues, RNase A and CHMO were recovered in 73% and 53% yield of soluble protein with full enzyme activity, respectively.

Conclusion

The refolding-facilitating media presented here could be a cost-efficient platform and should be applicable to refold a wide range of E. coli inclusion bodies in high yield with biological function.
Color Removal from Acid and Reactive Dye Solutions by Electrocoagulation and Electrocoagulation/Adsorption Processes
Authors: Bellebia S. , Kacha S. , Bouberka Z. , Bouyakoub A. Z. , Derriche Z.
Published: March 2009

In this study, electrocoagulation of Marine Blue Erionyl MR (acid dye) and electrocoagulation followed by adsorption of Brilliant Blue Levafix E‐BRA (reactive dye) from aqueous solutions were investigated, using aluminum electrodes and granular activated carbon (GAC). In the electrocoagulation and adsorption of dyestuff solutions, the effects of current density, loading charge, pH, conductivity, stirring velocity, contact time, and GAC concentration were examined. The optimum conditions for the electrocoagulation process were identified as loading charges 7.46 and 1.49 F/m 3, for a maximum abatement of 200 mg/L reactive and acid dye, respectively. The residual reactive dye concentration was completely removed with 700 mg/L GAC. The results of this investigation provide important data for the development of a combined process to remove significant concentrations of recalcitrant dyes from water, using moderate activated carbon energy and aluminum consumption, and thereby lowering the cost of treatment.
Short‐Term Effect of Capping on Microbial Communities in Freshwater Sediments
Authors: Wang Qi , Kassem Issmat I. , Sigler Von , Gruden Cyndee
Published: March 2009

Because biogas bubbles can influence cap integrity, the effect of capping and cap material on the ebullition potential in sediments must be studied. The goal of this comprehensive study was to determine the short‐term effect of capping regime on the activity, metabolic potential, and community structure of sediment microorganisms. To evaluate the effect of capping (sand, synthetic aggregate, and no cap) on microbial communities (i.e., nitrifiers and methanogens), sediments were collected from the Anacostia River (Washington, D.C.). Microbial communities in sand‐capped sediments exhibited the highest activity (tetrazolium redox dye, fluorescein diacetate hydrolysis assay, and biogas production), while communities in uncapped sediments exhibited the highest metabolic diversity. Substantial changes in microbial community structure (denaturing gradient gel electrophoresis) did not occur as a result of capping. Our data showed that the nature and magnitude of the effect that capping can have on microbial activity (biogas production) will likely be dependent on the capping materials chosen.
A Procedure to Estimate Proximate Analysis of Mixed Organic Wastes
Authors: Zaher U. , Buffiere P. , Steyer J.‐P. , Chen S.
Published: March 2009

In waste materials, proximate analysis measuring the total concentration of carbohydrate, protein, and lipid contents from solid wastes is challenging, as a result of the heterogeneous and solid nature of wastes. This paper presents a new procedure that was developed to estimate such complex chemical composition of the waste using conventional practical measurements, such as chemical oxygen demand (COD) and total organic carbon. The procedure is based on mass balance of macronutrient elements (carbon, hydrogen, nitrogen, oxygen, and phosphorus [CHNOP]) (i.e., elemental continuity), in addition to the balance of COD and charge intensity that are applied in mathematical modeling of biological processes. Knowing the composition of such a complex substrate is crucial to study solid waste anaerobic degradation. The procedure was formulated to generate the detailed input required for the International Water Association (London, United Kingdom) Anaerobic Digestion Model number 1 (IWA‐ADM1). The complex particulate composition estimated by the procedure was validated with several types of food wastes and animal manures. To make proximate analysis feasible for validation, the wastes were classified into 19 types to allow accurate extraction and proximate analysis. The estimated carbohydrates, proteins, lipids, and inerts concentrations were highly correlated to the proximate analysis; correlation coefficients were 0.94, 0.88, 0.99, and 0.96, respectively. For most of the wastes, carbohydrate was the highest fraction and was estimated accurately by the procedure over an extended range with high linearity. For wastes that are rich in protein and fiber, the procedure was even more consistent compared with the proximate analysis. The new procedure can be used for waste characterization in solid waste treatment design and optimization.
Effectiveness of the user interface driven system design using UML
Authors: Mrdalj Stevan , Scazzero Joseph , Jovanovic Vladan
Published: March 2009

The majority of research regarding the effectiveness of object-oriented analysis and design (OOAD) is focused on a comparison of object-oriented to traditional approaches that highlights their relative strengths and weaknesses. There has been less focus on improving OOAD on its own. The standardization of the Unified Modeling Language (UML) creates an opportunity to focus on improving the methods of developing UML diagrams. Design quality can be a litmus test for overall system quality. Practice has shown that designing user interfaces before domain modeling can be used on a systematic basis to derive other UML diagrams for a large class of interactive information systems. This empirical study analyzed 43 OOAD projects to determine the effectiveness of the user interface driven system design (UIDD) by calculating defect densities for four UML diagrams. The study was performed on three levels: individual type of defect, type of diagram and entire project. Empirical results show that the UIDD consistently produced very low defect densities on all three levels for projects that varied widely with respect to application area, information system type, team experience and size.
The role of ontological engineering for AIED research
Authors: Mizoguchi Riichiro
Published: March 2009

Ontology has been collecting a lot of attention recently. In fact, it has potential for resolving several key problems such as semantic tag design for semantic web, semantic integration, knowledge sharing/reuse, etc. However, it is also true that people have different understanding of ontology. This article is written to contribute to clarification of the understanding of ontology and ontological engineering and to promotion of its utility. Although the discussion is made in the context of Artificial Intelligence in Education domain, I believe the content is pretty general.
ElGamal Public-Key cryptosystem in multiplicative groups of quotient rings of polynomials over finite fields
Authors: El-Kassar A.N. , Haraty Ramzi
Published: March 2009

The ElGamal encryption scheme is described in the setting of any finite cyclic group G. Among the groups of most interest in cryptography are the multiplicative group Zp of the ring of integers modulo a prime p, and the multiplicative groups F2m of finite fields of characteristic two. The later requires finding irreducible polynomials H(x) and constructing the quotient ring Z2[x]/ < h(x)>. El-Kassar et al. modified the ElGamal scheme to the domain of Gaussian integers. El-Kassar and Haraty gave an extension in the multiplicative group of Zp[x]/ < x2 >. Their major finding is that the quotient ring need not be a field. In this paper, we consider another extension employing the group of units of Z2[x]/ < h(x) >, where H(x) = h1(x)h2(x)..Hr(x)is a product of irreducible polynomials whose degrees are pairwise relatively prime. The arithmetic needed in this new setting is described. Examples, algorithms and proofs are given. Advantages of the new method are pointed out and comparisons with the classical case of F2m are made.
Ambient Intelligence: Concepts and applications
Authors: Augusto Juan , Mccullagh Paul
Published: March 2009

Ambient Intelligence aims to enhance the way people interact with their environment to promote safety and to enrich their lives. A Smart Home is one such system but the idea extends to hospitals, public transport, factories and other environments. The achievement of Ambient Intelligence largely depends on the technology deployed (sensors and devices interconnected through networks) as well as on the intelligence of the software used for decision-making. The aims of this article are to describe the characteristics of systems with Ambient Intelligence, to provide examples of their applications and to highlight the challenges that lie ahead, especially for the Software Engineering and Knowledge Engineering communities. In particular we address system specification and verification for the former and knowledge acquisition from the vast amount of data collected for the latter. .
Building an advanced invariant real-time human tracking system
Authors: Idris Fayez , Abu Zaher , Rasras Rashad , El Emary
Published: March 2009

Real-time human tracking is very important in surveillance and robot applications. We note that the performance of any human tracking system depends on its accuracy and its ability to deal with various human sizes in a fast way. In this paper, we combined the presented works in [1, 2] to come with new human tracking algorithm that is robust to background and lighting changes and does not require special hardware components. In addition this system can handle various scales of human images. The proposed system uses sum of absolute difference (SAD) with thresholding as has been described in [2] and compares the output with the predefined person pattern using the technique which has been described in [1]. Using the combination between [1,2] approaches will enhance the performance and speed of the tracking system since pattern matching has been performed according to just one pattern. After matching stage, a specific file is created for each tracked person, this file includes image sequences for that person. The proposed system handles shadows removal, lighting changes, and background changes with infinite pattern scales using standard personal computer.
Using customizable properties to make object representation a first-class citizen
Authors: Vanderkimpen Koen , van Dooren , Steegmans Eric
Published: March 2009

Many object-oriented programming languages use fields to represent object state. This representation however, cannot be altered sufficiently when subclassing. Moreover, in languages such as Java and C#, proper encapsulation of fields necessitates a lot of boilerplate code. In this paper, we introduce our concept of properties, which are far more flexible for use with inheritance and greatly reduce boilerplate code compared to C# properties. Using our properties makes it easier for programmers to model programs in a more consistent manner. Furthermore, our Properties allow redefining an object's attributes in ways that equal the possibilities for redefinition of virtual methods in many programming languages, which makes them better suited to deal with unanticipated reuse. Specifically, using our construct, it becomes possible to join several superclass attributes into only one at the subclass level, conjointly decreasing memory consumption.
On syntax-directed adjoint fortran code
Authors: Naumann Uwe , Riehme Jan
Published: March 2009

Gradients of high-dimensional functions can be computed efficiently and with machine accuracy by so-called adjoint codes. We present an L-attributed grammar for the single-pass generation of intraprocedural adjoint code for a subset of Fortran. Our aim is to integrate the syntax directed approach into the front-end of the NAGWare Fortran compiler. Research prototypes of this compiler that build adjoint code based on an abstract intermediate representation have been developed for several years. We consider the syntax-directed generation of adjoint code as a low development cost alternative to more sophisticated algorithms. The price to pay comes in form of a very limited set of code optimizations that can be performed in a single-pass setting.
Applicability of Weyuker's properties on OO metrics: Some misunderstandings
Authors: Misra Sanjay , Akman Ibrahim
Published: March 2009

Weyuker's properties have been suggested as a guiding tool in identification of a good and comprehensive complexity measure by several researchers. Weyuker proposed nine properties to evaluate complexity measure for traditional programming. However, they are extensively used for evaluating object-oriented (OO) metrics, although the object-oriented features are entirely different in nature. In this paper, two recently reported OO metrics were evaluated and, based on it; the usefulness and relevance of these properties for evaluation purpose for object-oriented systems is discussed.
Previously Associated Type 2 Diabetes Variants May Interact With Physical Activity to Modify the Risk of Impaired Glucose Regulation and Type 2 Diabetes
Authors: Brito Ema C. , Lyssenko Valeriya , Renström Frida , Berglund Göran , Nilsson Peter M. , Groop Leif , Franks Paul W.
Published: March 2009

OBJECTIVE

Recent advances in type 2 diabetes genetics have culminated in the discovery and confirmation of multiple risk variants. Two important and largely unanswered questions are whether this information can be used to identify individuals most susceptible to the adverse consequences of sedentary behavior and to predict their response to lifestyle intervention; such evidence would be mechanistically informative and provide a rationale for targeting genetically susceptible subgroups of the population.

RESEARCH DESIGN AND METHODS

Gene × physical activity interactions were assessed for 17 polymorphisms in a prospective population-based cohort of initially nondiabetic middle-aged adults. Outcomes were 1) impaired glucose regulation (IGR) versus normal glucose regulation determined with either fasting or 2-h plasma glucose concentrations (n = 16,003), 2) glucose intolerance (in mmol/l, n = 8,860), or 3) incident type 2 diabetes (n = 2,063 events).

RESULTS

Tests of gene × physical activity interactions on IGR risk for 3 of the 17 polymorphisms were nominally statistically significant:CDKN2A/B rs10811661 (Pinteraction = 0.015), HNF1B rs4430796 (Pinteraction = 0.026), and PPARG rs1801282 (Pinteraction = 0.04). Consistent interactions were observed for the CDKN2A/B (Pinteraction = 0.013) and HNF1B (Pinteraction = 0.0009) variants on 2-h glucose concentrations. Where type 2 diabetes was the outcome, only one statistically significant interaction effect was observed, and this was for the HNF1B rs4430796 variant (Pinteraction = 0.0004). The interaction effects for HNF1B on IGR risk and incident diabetes remained significant after correction for multiple testing (Pinteraction = 0.015 and 0.0068, respectively).

CONCLUSIONS

Our observations suggest that the genetic predisposition to hyperglycemia is partially dependent on a person's lifestyle.
Association of 20-Year Changes in Cardiorespiratory Fitness With Incident Type 2 Diabetes
Authors: Carnethon Mercedes R. , Sternfeld Barbara , Schreiner Pamela J. , Jacobs David R. , Lewis Cora E. , Liu Kiang , Sidney Stephen
Published: March 2009

OBJECTIVE

To test the association of fitness changes over 7 and 20 years on the development of diabetes in middle age.

RESEARCH DESIGN AND METHODS

Fitness was determined based on the duration of a maximal graded exercise treadmill test (Balke protocol) at up to three examinations over 20 years from 3,989 black and white men and women from the Coronary Artery Risk Development in Young Adults study. Relative fitness change (percent) was calculated as the difference between baseline and follow-up treadmill duration/baseline treadmill duration. Diabetes was identified as fasting glucose ≥126 mg/dl, postload glucose ≥200 mg/dl, or use of diabetes medications.

RESULTS

Diabetes developed at a rate of 4 per 1,000 person-years in women (n = 149) and men (n = 122), and lower baseline fitness was associated with a higher incidence of diabetes in all race-sex groups (hazard ratios [HRs] from 1.8 to 2.3). On average, fitness declined 7.6% in women and 9.2% in men over 7 years. The likelihood of developing diabetes increased per SD decrease (19%) from the 7-year population mean change (−8.3%) in women (HR 1.22 [95% CI 1.09–1.39]) and men (1.45 [1.20–1.75]) after adjustment for age, race, smoking, family history of diabetes, baseline fitness, BMI, and fasting glucose. Participants who developed diabetes over 20 years experienced significantly larger declines in relative fitness over 20 years versus those who did not.

CONCLUSIONS

Low fitness is significantly associated with diabetes incidence and explained in large part by the relationship between fitness and BMI.
A Theoretical Challenge: Transition-Metal Compounds
Authors: Reiher Markus
Published: March 2009

Quantum chemistry meets one of its greatest challenges in the field of transition-metal compounds capable of fascinating chemical transformations. Complicated electronic structure and interesting chemistry are intimately connected, and the theoretical elucidation of such molecular processes
requires computational procedures that are both feasible and accurate. In this review we elaborate on our recent work in the field.
Exploring Metal Ion Coordination to Nucleic Acids by NMR
Authors: Johannsen Silke , Korth Maximiliane M. T. , Schnabl Joachim , Sigel Roland K. O.
Published: March 2009

Metal ions play a crucial role in charge compensation, folding and stabilization of tertiary structures of large nucleic acids. In addition, they may be directly involved in the catalytic mechanism of ribozymes. Most metal ions applied in the context of nucleic acids in vivo
and in vitro bind in a kinetically labile fashion. Hence, the detection of metal ion binding sites, not to mention the elucidation of the specific coordination sphere, still poses largely unresolved problems. Here we describe the different strategies applied and the progress made over
the last years to characterize metal ion coordination to large nucleic acids by NMR.
Collection of the BD SurePath Pap Test with a broom device plus endocervical brush improves disease detection when compared to the broom device alone or the spatula plus endocervical brush combination
Authors: Davis-Devine Sharon , Day Sarah J. , Anderson Amy , French Ashley , Madison-Henness Darcy , Mohar Naomi , Tansy Danielle , Hiremath Adarsh , Douglas Jeffrey A. , Freund Gregory G.
Published: March 2009

Objective:

Here we examine the diagnostic utility of the US Food And Drug Administration (FDA) approved Spatula + endocervical brush combination for the BD SurePath Pap Test (SPPT) and compare it to SPPT collection with the broom alone or to an off-label combination of broom + EC brush. This question is important due to lingering concerns over the value of EC detection to a satisfactory Pap test.

Methods:

20,125 SPPT vials were examined for the collection devices contained. The SPPT collection device combinations allowed were: Rovers Cervex-Brush (broom, FDA approved), Medscand Pap Perfect Spatula + Medscand CytoBrush Plus GT (spatula + GT brush, FDA approved) or Rovers Cervex-Brush + Surgipath C-E Brush (broom + CE brush, off label).

Results:

Examination of SPPT vials revealed 11,130 collected with the broom, 4,687 collected with the spatula + GT brush and 2,921 collected with the broom + CE brush. Absence of an endocervical/transformation zone was seen in 22.86% of broom cases, 13.10% of spatula + GT brush cases (p= 0.00005 vs broom) and 10.17% of broom + CE brush cases (p= 0.00005 vs broom, p= 0.00005 vs spatula + GT brush). Importantly, LSIL detection was: broom 2.99%; spatula + GT brush 2.45% (p= 0.053 vs broom); broom + CE brush 4.18% (p= 0.034 vs broom, p= 0.0001 vs spatula + GT brush).

Conclusion:

When broom + brush combination is compared to broom alone or to spatula + GT brush, the broom + CE brush combination better sampled the endocervical/transformation zone and increased LSIL detection.
Optimierung einer Vergärungsanlage für organische Abfälle durch Zugabe von Kobalt
Authors: Kübler H. , Scherer P. A. , Nimmrichter R.
Published: March 2009

Aus der Literatur ist bekannt, dass anaerobe, Essigsäure umsetzende und methanbildende Bakterien ein verstärktes Kobaltbedürfnis haben. Deshalb kann die Leistungsfähigkeit einer Vergärungsanlage durch einen Mangel an Kobalt limitiert sein. Die Untersuchungen bestätigen, dass im vorliegenden Fall die Vergärung einer Mischung aus kommunalen und gewerblichen Bioabfällen einer Limitierung durch Mangel an Kobalt unterlag und erbrachten somit erstmalig den Nachweis, dass auch bei einer Bioabfallvergärung ein Kobaltmangel auftreten kann. Ferner zeigten sie, dass Batch‐Gärtests, die gemäß der VDI‐Richtlinie 4630 mit ungewaschenem Klärschlamm durchgeführt wurden, auf einen Spurenelementmangel keinen sicheren Hinweis lieferten. Eine Kobaltdosierung erhöhte die Durchsatzleistung der Faulung und steigerte gleichzeitig die Biogasrate um fast 17  %. Trotz Verkürzen der hydraulischen Verweilzeit von 17 auf 12 Tage konnte die Biogasausbeute gesteigert werden (+3 %). Dabei können die zusätzlichen Chemikalienkosten durch die höheren Erlöse aus der Einspeisung des aus dem Biogas erzeugten elektrischen Stroms kompensiert werden.
Prozessdatenvalidierung in der Rektifikation
Authors: Keller T. , Arlt W. , Paul A. , Bauer M. H.
Published: March 2009

Die Bilanzierung stationärer Prozesse wie Rektifikationen führt oft aufgrund von fehlerbehafteten Messwerten zu nicht geschlossenen Massenbilanzen. Mit der Prozessdatenvalidierung steht ein statistisches Tool zur Verfügung, das aus den widersprüchlichen Messwerten den statistisch wahrscheinlichsten Prozesszustand ermittelt. Der vorliegende Beitrag zeigt die Vorgehensweise der Prozessdatenvalidierung einer Rektifikation unter Verwendung von Microsoft Excel.
Oxidation of low concentrations of hydrogen sulfide by air on a fixed activated carbon bed
Authors: Kaliva A. N. , Smith J. W.
Published: March 2009

As part of a study to evaluate the performance of a “dry” catalytic method of removing low concentrations of H2S from cupola gas, the rate of oxidation of low concentrations of H2S by air at room temperature has been studied using a fixed activated carbon bed. Previous studies have presented somewhat contradictory results.

It was found that the rate decreased with time, consistent with a rapidly fouling catalyst, and finally attained a steady state value. A mechanism is presented which is in agreement with the results.

The oxidation rate was also found to increase drastically by increasing the air humidity, contrary to the published results of some other workers.