bluuebunny/crossref_metadata_2025 huggingface dataset:
Benthic algal communities: recovery from experimental acidificationThis paper is part of the series “Forty Years of Aquatic Research at the Experimental Lakes Area”.
Authors: Turner Michael A. , Findlay David L. , Baulch Helen M. , Armstrong Llwellyn M. , Kasian Susan E. M. , McNicol Donald K. , Vinebrooke Rolf D.
Published: October 2009

Chemical recovery is hypothesized to promote rapid recovery of benthic algal communities in formerly acidified lakes; this expectation needs modification. We evaluated the hypothesis in a small lake (L302S) in the boreal forest of northwestern Ontario, Canada, during a decade of pH recovery following a prior decade of experimental acidification from pH 6.7 to 4.5. To account for regional changes during the study, we also studied a nearby reference lake (L239). Taxonomic changes in the epilithon (biofilm on rock surfaces) included persistently lower cyanobacterial biomass following its acidification-related decline and increases in both diatoms and greens. Epilithic metabolic recovery was incomplete because the acidification-induced increase in respiration continued, although the prior decline in photosynthesis was reversed. Unexpectedly, blooms of metaphytic filamentous green algae occurred at higher pH during recovery than during acidification. Although several community attributes recovered fully, recovery of many aggregate functional and taxonomic properties lagged improvements in pH. Divergence was greater at the taxonomic than at the functional level. Despite pH recovery, potential causes of incomplete algal recovery include incomplete chemical recovery and the persistent absence of functionally important biota. Our findings counter the assumption that ecological recovery mirrors the pathway of damage caused by a human stressor.
Assimilation of freshwater salmonid aquaculture waste by native aquatic biotaThis paper is part of the series “Forty Years of Aquatic Research at the Experimental Lakes Area”.
Authors: Kullman Marilynn A. , Kidd Karen A. , Podemski Cheryl L. , Paterson Michael J. , Blanchfield Paul J.
Published: October 2009

An experimental finfish aquaculture farm was operated in a small lake at the Experimental Lakes Area in northwestern Ontario, Canada. In this study, we used the distinct and enriched carbon and nitrogen isotope ratios (δ13C and δ15N) of rainbow trout ( Oncorhynchus mykiss ) feed and waste to determine whether the operation provided a novel source of energy for native biota. For 1 year prior to and for 3 years during the cage culture, we collected littoral, pelagic, and profundal invertebrates and minnows from the experimental and reference lakes. In both the second and third years of aquaculture, there was a significant increase in δ15N of all organisms sampled in the experimental lake; mean δ15N values of littoral, pelagic, and profundal invertebrates and minnows shifted towards the signature of the fish feed by up to 4.2‰. Significant increases in δ13C of up to 2.6‰ were observed in Mysis , profundal chironomids, and minnows but not in littoral invertebrates or zooplankton. Aquaculture waste became a progressively more important component of minnow diets over the course of this study. The dissolved and (or) particulate wastes of the cage operation became a novel source of energy for the native biota in this experimental lake.
Tree establishment and microhabitat relationships in north Swedish peatlands
Authors: Ohlson Mikael , Zackrisson Olle
Published: October 2009

We sowed seeds of Pinussylvestris L., Pinuscontorta Dougl, Piceaabies (L.) Karst., and Piceamariana (Mill.) B.S.P. at five different virgin peatland sites in northern Sweden. Seeds were sown in 1987, 1988, 1989, and 1990. The seeds were sown in three different types of microhabitat, viz Pleurozium, Sphagnumfuscum, and Sphagnumangustifolium. Germination and seedling mortality were monitored each year. Both germination and mortality were significantly affected by the micro-habitat. Sphagnumangustifolium microhabitats were most favourable and Pleurozium microhabitats were least favourable for germination of all tree species. In contrast, the mortality for all tree species was highest in Sphagnumangustifolium microhabitats and lowest in Pleurozium microhabitats. Lowest average mortality was found among the nonindigenous Pinuscontorta and Piceamariana. The coniferous tree species had a species-specific relationship with the microhabitat. Pinussylvestris seeds were the most able to germinate in the Pleurozium microhabitats, and seedling mortality was strongly affected by the microhabitat. Piceaabies was the least affected by the microhabitat, and seedling mortality was high irrespective of microhabitat.
Vertical distribution of roots along a soil toposequence in the New Jersey Pinelands
Authors: Ehrenfeld Joan G. , Kaldor Eric , Parmelee Robert W.
Published: October 2009

Root biomass was determined for four sites on each of two toposequences in the New Jersey Pinelands. The sites have similar plant species composition, disturbance histories, and soil parent materials; the soils at the different topographic positions vary principally in the thickness of the organic horizon. Each toposequence consisted of lowland, transition, and upland sites, plus a site in the pygmy pine stands found on exposed topographic rises within the region. Root biomass was determined for three depths (organic horizon, 0–10 cm and 10–20 cm mineral soil) and three size classes (<1, 1–5, and >5 mm). Total, fine, and intermediate root biomass was greatest at lowland sites and least at sites in the pygmy pine stands. Total and fine root biomass in both the forest floor and also the upper mineral layer was linearly related to thickness of the organic horizon. The percent allocation of roots among soil layers, and the percentage of roots in different size classes within each soil depth interval, were similar for lowland, transition, and upland sites. The pygmy pine stands, in contrast, had higher relative quantities of total and fine roots in the mineral soil than in the organic horizon. In the organic horizons at all topographic positions, 50–100% of the roots are fine roots, whereas only 10–20% of the roots in the mineral layers are fine roots. Although root biomass per unit area varies >2-fold from lowland to pygmy sites, biomass per unit volume of organic material does not vary among topographic positions. Volumes of organic matter are more densely filled with roots than are comparable volumes of mineral soil. Implications for the role of roots in nutrient cycling in different soil horizons are discussed.
Rootstock and scion effects on carbohydrates and mineral nutrients in loblolly pine
Authors: Jayawickrama K.J.S. , McKeand S.E. , Jett J.B. , Young E.
Published: October 2009

Variation in scion physiology caused by rootstock families, scion clones, and the rootstock–scion interactions were studied in loblolly pine (Pinustaeda L.). Ten full-sib families were used as rootstocks, and six scion clones were grafted on the rootstocks in all combinations. The trees were measured during and after the 2nd year after grafting; the traits measured were needle carbohydrate (starch, sucrose, and hexoses) concentrations and needle N, P, K, Ca, and Mg concentrations. These traits were measured in early fall and early spring. There were highly significant differences among scion clones for all traits. Rootstocks significantly affected hexoses in fall, total sugars in spring, P, K, Ca, and Mg in fall, and Ca and Mg in spring. For most traits the largest variance component was within each rootstock-scion combination; next largest were those for scion clones. Variance components for rootstocks were small or negative for most traits, indicating that the scion has more control than the rootstock on scion physiology of young grafted loblolly pine.
PARTITION FUNCTIONS OF MATRIX MODELS AS THE FIRST SPECIAL FUNCTIONS OF STRING THEORY II: KONTSEVICH MODEL
Authors: ALEXANDROV A. , MIRONOV A. , MOROZOV A. , PUTROV P.
Published: October 2009

In the paper Int. J. Mod. Phys. A19, 4127 (2004), we started a program of creating a reference-book on matrix-model τ-functions, the new generation of special functions, which are going to play an important role in string theory calculations. The main focus of that paper was on the one-matrix Hermitian model τ-functions. The present paper is devoted to a direct counterpart for the Kontsevich and Generalized Kontsevich Model (GKM) τ-functions. We mostly focus on calculating resolvents (= loop operator averages) in the Kontsevich model, with a special emphasis on its simplest (Gaussian) phase, where exists a surprising integral formula, and the expressions for the resolvents in the genus zero and one are especially simple (in particular, we generalize the known genus zero result to genus one). We also discuss various features of generic phases of the Kontsevich model, in particular, a counterpart of the unambiguous Gaussian solution in the generic case, the solution called Dijkgraaf–Vafa (DV) solution. Further, we extend the results to the GKM and, in particular, discuss the p–q duality in terms of resolvents and corresponding Riemann surfaces in the example of dualities between (2, 3) and (3, 2) models.
Late Devonian tetrapod habitats indicated by palaeosols in Pennsylvania
Authors: Retallack G.J. , Hunt R.R. , White T.S.
Published: October 2009

Late Devonian (Famennian) tetrapods from the Duncannon Member of the Catskill Formation, near Hyner (Pennsylvania, USA) have been found within palaeosols that offer a new line of evidence for their ancient environments. Hyner has yielded at least two fossil tetrapod species,
Hynerpeton basseti
and
Densignathus rowei
. Subhumid Vertisol palaeosols and semiarid Aridisol palaeosols alternate at Hyner, as in other Catskill Formation sedimentary cycles attributed to Milankovitch-eccentricity periods (100 ka). Tetrapods were found in palaeosols of subhumid, not semiarid, phases of 100 ka palaeoclimate cycles. In addition, palaeosols at Hyner record an unusually warm and wet climatic episode compared with other palaeosols of the Catskill Formation, and correlated with the European
Annulata
black shale event. Tetrapod bones are cracked and disarticulated in red palaeosols of an oxbow lake margin, as if victims of dry-season death, decay, and subaerial weathering. Vegetation-choked swales and floodplains would have afforded shelter from 3–4 m long predatory fish (
Hyneria lindae
) of open water, and offered food of large dead fish, small live fish, arachnids, myriapods and scorpions. If these early tetrapods lived on land at all, it was during wet seasons of feeding and breeding, rather than fatally dry seasons.

Supplementary material:

Chemical data are available at
http://www.geolsoc.org.uk/SUP18373
.
Exhumation of an active magmatic–hydrothermal system in a resurgent caldera environment: the example of Ischia (Italy)
Authors: Sbrana A. , Fulignati P. , Marianelli P. , Boyce A.J. , Cecchetti A.
Published: October 2009

Ischia is a rare case of a well-exposed caldera system that has experienced rapid recent resurgence, which can be used to dissect the anatomy of an otherwise inaccessible active hydrothermal system developed in a caldera-forming environment. Integrated analyses of melt and fluid inclusions, mineralogy and stable isotopic compositions of pumices, tuffs and syenitic xenoliths of the Ischia volcanic system provide strong physico-chemical constraints on the shallow magmatic reservoir and the hydrothermal system. The hydrothermal system has been exposed by the rapid uplift of the Mt. Epomeo resurgent block. The engine of the hydrothermal system of Ischia can be identified in the shallow magmatic system (at around 2 km depth) that hosts hot (
c
. 1000 °C) trachytic magma. The hydrothermal system developed principally within thick intracaldera ignimbrite deposits, and extended to a depth of at least 1 km, defining a series of facies characterized by associations of alteration mineral assemblages typical of a seawater-dominated high-temperature geothermal system.

Supplementary material:

Sample descriptions and analytical methods are available at
http://www.geolsoc.org.uk/SUP18371
.
The gravity fields of Palawan and New Caledonia: insights into the subsurface geometries of ophiolites
Authors: Milsom John , Barretto Jenny , Aguda Nancy , Bringas Dennis , Ho Romeo , Aitchison Jonathan
Published: October 2009

New gravity data from Palawan, in the western Philippines, emphasize resemblances to New Caledonia. On both islands, ophiolites derived from root zones just offshore rest on basal surfaces that change abruptly in depth by as much as 5 km. The subsurface geometries of these thrust sheets are as important to an understanding of their emplacement histories as are their exposure patterns.
Global Neoproterozoic petroleum systems: the emerging potential in North Africa
Authors: Craig Jonathan , Thurow Juergen , Thusu Bindra , Whitham Andy , Abutarruma Yousef
Published: October 2009

The Neoproterozoic Eon is relatively poorly known from a petroleum perspective, despite the existence of producing, proven and potential plays in many parts of the world. In tectonic, climatic and petroleum systems terms, the Neoproterozoic to Early Cambrian period can be divided into three distinct phases: a Tonian to Early Cryogenian phase, prior to about 750 Ma, dominated by the formation, stabilization and initial break-up of the supercontinent of Rodinia; a mid Cryogenian to Early Ediacaran phase (
c
. 750–600 Ma) including the major global-scale ‘Sturtian’ and ‘Marinoan’ glaciations and a mid Ediacaran to Early Cambrian (
c
. post 600 Ma) phase corresponding with the formation and stabilization of the Gondwana Supercontinent. There is increasing evidence that deposition of many mid to late Neoproterozoic (to Early Palaeozoic) organic-rich units was triggered by strong post-glacial sea level rise on a global scale, following the ‘Snowball Earth’ type glaciations, coupled with basin development and rifting on a more local scale.

Fieldwork in North Africa including the Taoudenni Basin in Mauritania, Algeria and Mali; the Anti-Atlas region of Morocco and the Cyrenaica, Kufra and Murzuk basins in Libya has added to the understanding of reservoir, source and seal relationships and confirmed the widespread presence of Precambrian stromatolitic carbonate units of potential reservoir facies. Current research on the chronostratigraphy, distribution and quality of source rocks, controls on reservoir quality and distribution of seals in the Precambrian–Early Cambrian hydrocarbon plays throughout South America, North Africa, the Middle East and the Indian Subcontinent is documented in this Special Publication.
Distribution of Infracambrian rocks and the hydrocarbon potential within the Murzuq and Al Kufrah basins, NW Africa
Authors: Aziz Abdussalam , Ghnia Sadeg
Published: October 2009

This paper presents an overview of the distribution of the Infracambrian rocks within the Murzuq and Al Kufrah basins obtained by integrating existing data and new outcrop and subsurface data, and discusses the implications for the regional depositional setting and hydrocarbon potential.

In the Murzuq Basin the Infracambrian units comprise volcaniclastics, metasediments and fine- to medium-grained sandstones with an average thickness of 61 m, reflecting a proximal, clastic-dominated depositional system.

In the Al Kufrah Basin carbonate facies in Jabal Arkanu (eastern margin) indicate that the distal facies may become organic-rich. Interpreted seismic lines reveal Infracambrian graben systems similar to those found elsewhere that provide good hydrocarbon source rocks in petroliferous basins.
Potential for oil and gas in the Proterozoic carbonates (Sirban Limestone) of Jammu, northern India
Authors: Bhat G. M. , Ram Ghara , Koul Sumita
Published: October 2009

The Proterozoic Sirban Limestone of Jammu in northern India contains an assemblage of Neoproterozoic microflora comparable to other such assemblages from different Proterozoic oil- and gas-bearing carbonate successions in India, Morocco and Siberia. The stromatolitic Sirban Limestone succession is composed of lamina-scale organic-rich source rocks, limestone units with good-quality reservoir characteristics and seal horizons that together constitute the basic physical elements of a petroleum system. A reworked microfloral assemblage of Neoproterozoic age is also recovered from the unconformably overlying Subathu Formation (Eocene) from the area. Somein situelements of this assemblage, including a few genera, were also recovered from the Sirban Limestone. This reworked assemblage may be related either to upwards migration of hydrocarbons from deeper sediments or, more likely, to the existence of the Sirban Limestone and younger Neoproterozoic formations as a positive area that sourced the microflora to the Eocene Subathu Basin.
Late Cryogenian (Neoproterozoic) glacial and post-glacial successions at the southern margin of the Congo Craton, northern Namibia: facies, palaeogeography and hydrocarbon perspective
Authors: Bechstädt Thilo , Jäger Hartmut , Spence Guy , Werner Georg
Published: October 2009

The geological paradox of at least two Neoproterozoic glacial intervals at tropical latitudes intercalated within carbonates remains an unsolved puzzle. Several conceptual models have been proposed to explain these apparent rapid swings between climatic extremes and the associated isotopic changes in sea-water chemistry. In Oman, post-glacial transgressive sedimentary successions represent important hydrocarbon source rocks. Source rock characteristics of Neoproterozoic post-glacial successions in other parts of the world (even if not directly correlatable) are, therefore, of special economic interest.

This paper concentrates on the Ghaub Formation diamictite interval in northern Namibia and the major environmental change in the aftermath of the assumed glaciation. The relationship of the post-glacial sediments with the underlying different types of cap carbonate and diamictite successions is discussed, and a model of the succession of events is presented. The palaeotopography, caused mostly by ongoing tectonic activity including uplift on the scale of thousands of metres, strongly influenced the petroleum system created and played an important role for the hydrocarbon prospectivity of this post-glacial succession. Tectonic activity on the shelf of the southern margin of the Congo Craton was repeated, and different sub-basins were created before, during and after the Ghaub glaciation. The newly formed relief was flooded, and the different sub-basins were affected by restricted circulation for quite some time. This general scenario bears many similarities to the late Ordovician–early Silurian petroleum system, also formed during post-glacial sea-level rise.
Peroxisome proliferator-activated receptor-γ regulates the expression and function of very-low-density lipoprotein receptor
Authors: Tao Huan , Aakula Srikanth , Abumrad Naji N. , Hajri Tahar
Published: October 2009

Very-low-density lipoprotein receptor (VLDLR) is a member of the low-density receptor family, highly expressed in adipose tissue, heart, and skeletal muscle. It binds apolipoprotein E-triglyceride-rich lipoproteins and plays a significant role in triglyceride metabolism. PPARγ is a primary regulator of lipid metabolism in adipocytes and controls the expression of an array of genes involved in lipid trafficking in adipocytes. However, it is not known whether VLDLR is also under the control of PPARγ. In this study, we investigated the role of PPARγ in the regulation of VLDLR expression and function in vivo and in vitro. During the differentiation of 3T3-L1 preadipocytes, the levels of VLDLR protein and mRNA increased in parallel with the induction of PPARγ expression and reached maximum in mature adipocytes. Treatment of differentiated adipocytes with PPARγ agonist pioglitazone upregulated VLDLR expression in dose- and time-dependent manners. In contrast, specific inhibition of PPARγ significantly downregulated the protein level of VLDLR. Induction of VLDLR is also demonstrated in vivo in adipose tissue of wild-type (WT) mice treated with pioglitazone. In addition, pioglitazone increased plasma triglyceride-rich lipoprotein clearance and increased epididymal fat mass in WT mice but failed to induce similar effects in vldlr−/−mice. These results were further corroborated by the finding that pioglitazone treatment enhanced adipogenesis and lipid deposition in preadipocytes of WT mice, while its effect in VLDLR-null preadipocytes was significantly blunted. These findings provide direct evidence that VLDLR expression is regulated by PPARγ and contributes in lipid uptake and adipogenesis.
Constitutively active calcineurin in skeletal muscle increases endurance performance and mitochondrial respiratory capacity
Authors: Jiang Lake Q. , Garcia-Roves Pablo M. , de Castro Barbosa Thais , Zierath Juleen R.
Published: October 2009

Expression of an activated form of calcineurin in skeletal muscle selectively up-regulates slow-fiber-specific gene expression. Here, we tested the hypothesis that expression of activated calcineurin in skeletal muscle influences body composition, energy homeostasis, and exercise performance. Using transgenic mice expressing activated calcineurin (CnA*) in skeletal muscle (MCK-CnA* transgenic mice), we determined whether skeletal muscle reprogramming by calcineurin activation affects exercise performance and skeletal muscle mitochondrial function. Body weight and extensor digitorum longus (EDL) skeletal muscle weight were reduced 10% in MCK-CnA* mice compared with wild-type littermates. Basal oxygen consumption, food intake, and voluntary exercise behavior were unchanged between MCK-CnA* and wild-type mice. However, when total energy expenditure was normalized by fat-free mass, energy expenditure was increased in MCK-CnA* mice. An endurance performance treadmill running test revealed MCK-CnA* mice are fatigue resistant and run 50% farther before exhaustion. After a standardized exercise bout, glycogen and triglyceride content in EDL muscle was higher in MCK-CnA* vs. wild-type mice. Mitochondrial respiratory capacity was increased 35% in EDL muscle from resting MCK-CnA* mice. In conclusion, our results provide evidence to support the hypothesis that calcineurin activation in skeletal muscle increases mitochondrial oxidative function and energy substrate storage, which contributes to enhanced endurance exercise performance. These adaptive changes occur as a consequence of a lifelong expression of a constitutively active calcineurin and mimic the response to chronic endurance training.
Edelman's equation is valid in acute hyponatremia in a porcine model: plasma sodium concentration is determined by external balances of water and cations
Authors: Overgaard-Steensen Christian , Larsson Anders , Bluhme Henrik , Tønnesen Else , Frøkiær Jørgen , Ring Troels
Published: October 2009

Acute hyponatremia is a serious condition, which poses major challenges. Of particular importance is what determines plasma sodium concentration ([Na+]). Edelman introduced an explicit model to describe plasma [Na+] in a population as [Na+] = α·(exchangeable Na++ exchangeable K+)/(total body water) − β. Evidence for the clinical utility of the model in the individual and in acute hyponatremia is sparse. We, therefore, investigated how the measured plasma [Na+] could be predicted in a porcine model of hyponatremia. Plasma [Na+] was estimated from in vivo-determined balances of water, Na+, and K+, according to Edelman's equation. Acute hyponatremia was induced with desmopressin acetate and infusion of a 2.5% glucose solution in anesthetized pigs. During 480 min, plasma [Na+] and osmolality were reduced from 136 (SD 2) to 120 mmol/l (SD 3) and from 284 (SD 4) to 252 mosmol/kgH2O (SD 5), respectively. The following interpretations were made. First, Edelman's model, which, besides dilution, takes into account Na+and K+, fits plasma [Na+] significantly better than dilution alone. Second, a common value of α = 1.33 (SD 0.08) and β = −13.04 mmol/l (SD 7.68) for all pigs explains well the plasma [Na+] in the individual animal. Third, measured exchangeable Na+and calculated exchangeable Na++ K+per weight in the pigs are close to Edelman's findings in humans, whereby the methods are cross-validated. In conclusion, plasma [Na+] can be explained in the individual animal by external balances, according to Edelman's construct in acute hyponatremia.
Differential vulnerabilities of urethral afferents in diabetes and discovery of a novel urethra-to-urethra reflex
Authors: Yang Zhongguang , Dolber Paul C. , Fraser Matthew O.
Published: October 2009

Urethral reflexes are important regulators of micturition, and impairment of urethral afferent neuronal function may disrupt coordinated bladder and urethral activity, thereby contributing to voiding dysfunction in lower urinary tract disorders. Chemical stimulation by intraurethral irritant solution perfusion was used to determine whether urethral afferent neuronal function is altered in diabetes mellitus (DM). Sprague-Dawley rats were studied 10 wk after streptozotocin injection to induce DM or vehicle alone. Escalating doses of capsaicin (0.1–30 μM) or acetic acid (0.01–1%; AA) were perfused intraurethrally while recording isovolumetric bladder activity, urethral perfusion pressure, and electromyography of the external urethral sphincter (EUS-EMG). Some rats were additionally treated with α-bungarotoxin, hexamethonium, or bilateral transection of the sensory branches of the pudendal nerves (PudSNx). Intraurethral capsaicin inhibited bladder contractions in six out of seven control rats but not in any of six DM rats. Low-frequency oscillations (LFOs) of intraurethral pressure were observed in five out of six control rats with capsaicin-induced bladder inhibition. In contrast, intraurethral AA inhibited bladder contractions and enhanced tonic EUS-EMG activity in six out of six control and five out of six DM rats. LFOs occurred in four out of six control and three of five DM rats with AA-induced bladder inhibition. Chemically induced bladder inhibition and LFOs were not prevented by α-bungarotoxin but were eliminated by PudSNx and hexamethonium. Finally, LFOs were followed by phasic EUS activity. These findings show that DM affects urethral afferent neurons differentially, compromising those expressing TRPV1 receptors. Urethral smooth muscle LFOs are neurogenically mediated and induce EUS activity, revealing the existence of a hitherto undescribed reflex pathway: a smooth-to-striated muscle urethra-to-urethra reflex.
Reactive oxygen species generated by renal ischemia and reperfusion trigger protection against subsequent renal ischemia and reperfusion injury in mice
Authors: Kim Jinu , Jang Hee-Seong , Park Kwon Moo
Published: October 2009

Ischemic preconditioning by a single event of ischemia and reperfusion (SIRPC) dramatically protects renal function against ischemia and reperfusion (I/R) induced several weeks later. We recently reported that reactive oxygen species (ROS) and oxidative stress were sustained in a kidney that had functionally recovered from I/R injury, thus suggesting an association between SIRPC and ROS and oxidative stress. However, the role of ROS in SIRPC remains to be clearly elucidated. To assess the involvement of ROS in SIRPC, mice were subjected to SIRPC (30 min of bilateral renal ischemia and 8 days of reperfusion) and then exposed to I/R injury. Thirty minutes of bilateral renal ischemia in the non-SIRPC mice resulted in a marked increase in plasma creatinine levels 4 and 24 h after reperfusion, which was not observed in the I/R in the SIRPC mice. SIRPC resulted in increases in the levels of kidney superoxide. Administrations of manganese(III) tetrakis(1-methyl-4-pyridyl) porphyrin [MnTMPyP; a cell-permeable superoxide dismutase (SOD) mimetic] and N-acetylcysteine (NAc; a ROS scavenger) to SIRPC mice blocked the SIRPC-induced increase in superoxide levels and removed ∼48–64% of the functional protection of the SIRPC kidney. Additionally, these administrations significantly inhibited I/R-induced increases in superoxide formation, hydrogen peroxide production, and lipid peroxidation, along with the inhibition of I/R-induced reductions in the expression and activity of manganese SOD, copper-zinc SOD, and catalase. Furthermore, administrations of MnTMPyP or NAc inhibited the SIRPC-induced increase in inducible nitric oxide synthase expression but did not inhibit the SIRPC-induced increases in heat shock protein-25 expression. In conclusion, the renoprotection afforded by SIRPC was triggered by ROS generated by SIRPC.
A New Hybrid Algorithm for Variational Inclusions, Generalized Equilibrium Problems, and a Finite Family of Quasi-Nonexpansive Mappings
Authors: Cholamjiak Prasit , Suantai Suthep
Published: October 2009

We proposed in this paper a new iterative scheme for finding common elements of the set of fixed points of a finite family of quasi-nonexpansive mappings, the set of solutions of variational inclusion, and the set of solutions of generalized equilibrium problems. Some strong convergence results were derived by using the concept of "Equation missing"-mappings for a finite family of quasi-nonexpansive mappings. Strong convergence results are derived under suitable conditions in Hilbert spaces.
A Survey of Collaborative Filtering Techniques
Authors: Su Xiaoyuan , Khoshgoftaar Taghi M.
Published: October 2009

As one of the most successful approaches to building recommender systems, collaborative filtering (CF) uses the known preferences of a group of users to make recommendations or predictions of the unknown preferences for other users. In this paper, we first introduce CF tasks and their main challenges, such as data sparsity, scalability, synonymy, gray sheep, shilling attacks, privacy protection, etc., and their possible solutions. We then present three main categories of CF techniques: memory-based, model-based, and hybrid CF algorithms (that combine CF with other recommendation techniques), with examples for representative algorithms of each category, and analysis of their predictive performance and their ability to address the challenges. From basic techniques to the state-of-the-art, we attempt to present a comprehensive survey for CF techniques, which can be served as a roadmap for research and practice in this area.
A Hardware Filesystem Implementation with Multidisk Support
Authors: Mendon Ashwin A. , Schmidt Andrew G. , Sass Ron
Published: October 2009

Modern High‐End Computing systems frequently include FPGAs as compute accelerators. These programmable logic devices now support disk controller IP cores which offer the ability to introduce new, innovative functionalities that, previously, were not practical. This article describes one such innovation: a filesystem implemented in hardware. This has the potential of improving the performance of data‐intensive applications by connecting secondary storage directly to FPGA compute accelerators. To test the feasibility of this idea, a Hardware Filesystem was designed with four basic operations (open, read, write, and delete). Furthermore, multi‐disk and RAID‐0 (striping) support has been implemented as an option in the filesystem. A RAM Disk core was created to emulate a SATA disk
drive so results on running FPGA systems could be readily measured. By varying the block size from 64 to 4096 bytes, it was found that 1024 bytes gave the best performance while using a very modest 7% of a Xilinx XC4VFX60′s slices and only four (of the 232) BRAM blocks available.
Permanence of a Discrete Nonlinear Prey‐Competition System with Delays
Authors: Lu Hongying
Published: October 2009

A discrete nonlinear prey‐competition system with m‐preys and
(n-m)‐predators and delays is considered. Two sets of sufficient conditions on the
permanence of the system are obtained. One set is delay independent, while
the other set is delay dependent.
Murine Pancreatic Beta TC3 Cells Show Greater2′,5′-Oligoadenylate Synthetase (2′5′AS) Antiviral Enzyme Activity and Apoptosis Following IFN-αor Poly(I:C) Treatment than Pancreatic Alpha TC3 Cells
Authors: Li M. , Zheng D.-J. , Field L. L. , Bonnevie-Nielsen V.
Published: October 2009

Type 1 diabetes is caused by autoimmune destruction of pancreatic beta cells, possibly virus initiated. Virus infection induces alpha-interferon (IFN-α), leading to upregulation of genes encoding double-stranded (ds) RNA-dependent antiviral enzymes2′,5′-oligoadenylate synthetase (2′5′AS) and PKR (p68). To investigate whether beta cell specificity could be due to antiviral differences between beta and alpha cells, we treated beta and alpha TC3 cell lines with IFN-αand/or poly(I:C) (a synthetic dsRNA). Results showed that, following IFN-αstimulation, increases in2′5′AS levels and activities were significantly higher in beta than alpha cells(P<.001), whereas increases in PKR level and activity were comparable in the two cell types. Poly(I:C) stimulated2′5′AS activity in beta but not alpha cells, and co-transfection IFN-αplus poly(I:C) induced apoptosis in beta but not alpha cells. These findings suggest that the elevated2′5′AS response of pancreatic beta cells could render them particularly vulnerable to damage and/or apoptosis during virus infection.
Analysis of Humid Air Turbine Cycle with Low‐ or Medium‐Temperature Solar Energy
Authors: Zhao Hongbin , Yue Pengxiu , Cao Ling
Published: October 2009

A new humid air turbine cycle that uses low‐ or medium‐temperature solar energy as assistant heat source was proposed for increasing the mass flow rate of humid air. Based on the combination of the first and second laws of thermodynamics, this paper described and compared the performances of the conventional and the solar HAT cycles. The effects of some parameters such as pressure ratio, turbine inlet temperature (TIT), and sollar collector efficiency on humidity, specific work, cycle′s exergy efficiency, and solar energy to electricity efficiency were discussed in detail. Compared with the conventional HAT cycle, because of the increased humid air mass flow rate in the new system, the humidity and the specific work of the new system were increased. Meanwhile, the solar energy to electricity efficiency was greatly improved. Additionally, the exergy losses of components in the system under the given conditions were also studied and analyzed.
Some Effects of Side Walls on Unsteady Flow of a Viscous Fluid over a Plane Wall
Authors: Erdoğan M. Emin , İmrak C. Erdem
Published: October 2009

Four types of unsteady flows of a viscous fluid over a plane wall bounded by two side walls are considered. They are flow caused by impulsive motion of a plate, flow due to oscillation of a plate, flow induced by constantly accelerating plate, and flow imposed by a plate that applies a constant tangential stress to the fluid. In order to solve these problems, the sine and cosine transformations are used, and exact solutions for the velocity distribution are found in terms of definite integrals. The cases for which the time goes to infinity and the distance between two side walls goes to infinity are compared with the cases for flows over a plane wall in the absence of the side walls. These provide to know the required time to attain the steady‐state and what is the distance between the side walls for which the measured value of the velocity or the stress would be unaffected by the presence of the side walls.
Nanocrystalline Metal Oxides for Methane Sensors: Role of Noble Metals
Authors: Basu S. , Basu P. K.
Published: October 2009

Methane is an important gas for domestic and industrial applications and its source is mainly coalmines. Since methane is extremely inflammable in the coalmine atmosphere, it is essential to develop a reliable and relatively inexpensive chemical gas sensor to detect this inflammable gas below its explosion amount in air. The metal oxides have been proved to be potential materials for the development of commercial gas sensors. The functional properties of the metal oxide‐based gas sensors can be improved not only by tailoring the crystal size of metal oxides but also by incorporating the noble metal catalyst on nanocrystalline metal oxide matrix. It was observed that the surface modification of nanocrystalline metal oxide thin films by noble metal sensitizers and the use of a noble metal catalytic contact as electrode reduce the operating temperatures appreciably and improve the sensing properties. This review article concentrates on the nanocrystalline metal oxide methane sensors and the role of noble metals on the sensing properties.
Subjective Risk Assessment and Perception in the Greek and English Bakery Industries
Authors: Alexopoulos Evangelos C. , Kavadi Zafira , Bakoyannis Giorgos , Papantonopoulos Sotiris
Published: October 2009

Several factors influencing risk perception in the area of occupational health and safety are known, but there is still lack of a full understanding of the ways in which people characterize risk. This study aimed to provide an insight of employee risk assessment and perception in the bakery industry. 87 British and 64 Greek employees in two comparable bakery companies were asked to estimate and evaluate hazards at their workplace. The participants' judgments of 12 hazards—according to 7 risk aspects—were collected and analyzed. Subjective assessment on important occupational hazards included handling heavy loads, repetitiveness, high temperatures, high rate of work, stressful deadlines, and noise. Although limited in the population involved, our findings revealed strong cross-national differences in employee risk perception of specific groups of hazards in the bakery industry. Additional interviews revealed evidence that Greek employees' risk perception depends mostly on work experience while British employees were aware of risks due to company health and safety policy, recognizing that safety is the responsibility of both the management and the worker. Cross-national (cultural) factors that influence workforce risk perception and attitudes towards safety have to be taken into account by technical experts and policy makers in the designing of prevention strategies and risk communication.
Minimizing Total Weighted Completion Time on Single Machine with Past‐Sequence‐Dependent Setup Times and Exponential Time‐Dependent and Position‐Dependent Learning Effects
Authors: Sun Kaibiao , Li Hongxing
Published: October 2009

This paper addresses a single‐machine problem in which the past‐sequence‐dependent (p‐s‐d) setup times and exponential time‐dependent and position‐dependent learning effects are considered. By the exponential time‐dependent learning effect, it means that the processing time of a job is defined by an exponent function of the total actual processing time of the already processed jobs. The setup times are proportional to the length of the already processed jobs. The aim is to minimize the total weighted completion time, this is an NP‐hard problem. Under certain conditions, it is shown that the classical WSPT rule is optimal for the problem.
Stability Analysis of a Delayed SIR Epidemic Model with Stage Structure and Nonlinear Incidence
Authors: Tian Xiaohong , Xu Rui
Published: October 2009

We investigate the stability of an SIR epidemic model with stage structure and time delay. By analyzing the eigenvalues of the corresponding characteristic equation, the local stability of each feasible equilibrium of the model is
established. By using comparison arguments, it is proved when the basic reproduction number is less than unity, the disease free equilibrium is globally asymptotically stable. When the basic reproduction number is greater than unity, sufficient
conditions are derived for the global stability of an endemic equilibrium of the model. Numerical simulations are carried out to illustrate the theoretical results.
Coincidence Theorems for Certain Classes of Hybrid Contractions
Authors: Singh SL , Mishra SN
Published: October 2009

Coincidence and fixed point theorems for a new class of hybrid contractions consisting of a pair of single-valued and multivalued maps on an arbitrary nonempty set with values in a metric space are proved. In addition, the existence of a common solution for certain class of functional equations arising in dynamic programming, under much weaker conditions are discussed. The results obtained here in generalize many well known results.
CXC Receptor-1 Silencing Inhibits Androgen-Independent Prostate Cancer
Authors: Shamaladevi Nagarajarao , Lyn Dominic A. , Escudero Diogo O. , Lokeshwar Bal L.
Published: October 2009

The CXC receptor-1 (CXCR1) is a coreceptor for interleukin-8 (IL-8) and is expressed on both normal and tumor cells. The function of CXCR1 in prostate cancer was investigated by silencing its expression, using RNA interference. We established stable cell colonies of PC-3 cells, depleted of CXCR1, using lentiviral plasmids (pLK0.1puro) generating small hairpin RNA (shRNA) against CXCR1 mRNA. Stable shRNA transfectants (PLK1–PLK5) that express significantly reduced CXCR1 mRNA (≥90% down) and protein (≥43% down) or vector-only transfectants (PC-3V) were characterized. PLK cells showed reduced cell proliferation (down, ≥66%), due to cell cycle arrest at G1-S phase, decreases in Cyclin D1, CDK4, phosphorylated Rb, and extracellular signal-regulated kinase 1/2 levels compared with those in PC-3V cells. CXCR1 depletion lead to increases in spontaneous apoptosis by mitochondria-mediated intrinsic mechanism and increases in proapoptotic proteins (BAD, 40%; BAX, 12%), but decreases in antiapoptotic proteins (BCL2, down 38%; BCLxL, 20%). PLK2 cells grew as slow-growing tumors (decrease of 54%), compared with that of PC3V tumors in athymic mice. Ex vivo analyses of PLK2 tumor tissues showed reduced expression of Cyclin D1 and vascular endothelial growth factor, and increased apoptosis activity. Other IL-8–expressing prostate cancer cell lines also exhibited similar phenotypes when CXCR1 was depleted by CXCR1 shRNA transfection. In contrast to these cells, CXCR1 depletion had little effect on IL-8 ligand–deficient LNCaP cells. RNA interference rescue using mutated CXCR1 plasmids reversed the silencing effect of PLK2, thus demonstrating the specificity of phenotypic alteration by CXCR1 shRNA. These studies establish that CXCR1 promotes IL-8–mediated tumor growth. [Cancer Res 2009;69(21):8265–74]
Epigenetic Inactivation of the Circadian Clock Gene BMAL1 in Hematologic Malignancies
Authors: Taniguchi Hiroaki , Fernández Agustin F. , Setién Fernando , Ropero Santiago , Ballestar Esteban , Villanueva Alberto , Yamamoto Hiroyuki , Imai Kohzoh , Shinomura Yasuhisa , Esteller Manel
Published: October 2009

Disruption of circadian rhythms, daily oscillations in biological processes that are regulated by an endogenous clock, has been linked to tumorigenesis. Normal and malignant tissues often show asynchronies in cell proliferation and metabolic rhythms. Cancer chronotherapy takes biological time into account to improve the therapy. However, alterations of the circadian clock machinery genes have rarely been reported in human cancer. Herein, we show that the BMAL1 gene, a core component of the circadian clock, is transcriptionally silenced by promoter CpG island hypermethylation in hematologic malignancies, such as diffuse large B-cell lymphoma and acute lymphocytic and myeloid leukemias. We also describe how BMAL1 reintroduction in hypermethylated leukemia/lymphoma cells causes growth inhibition in colony assays and nude mice, whereas BMAL1 depletion by RNA interference in unmethylated cells enhances tumor growth. We also show that BMAL1 epigenetic inactivation impairs the characteristic circadian clock expression pattern of genes such as C-MYC, catalase, and p300 in association with a loss of BMAL1 occupancy in their respective promoters. Furthermore, the DNA hypermethylation–associated loss of BMAL1 also prevents the recruitment of its natural partner, the CLOCK protein, to their common targets, further enhancing the perturbed circadian rhythm of the malignant cells. These findings suggest that BMAL1 epigenetic inactivation contributes to the development of hematologic malignancies by disrupting the cellular circadian clock. [Cancer Res 2009;69(21):8447–54]
Enhanced Antitumor Activity Induced by Adoptive T-Cell Transfer and Adjunctive Use of the Histone Deacetylase Inhibitor LAQ824
Authors: Vo Dan D. , Prins Robert M. , Begley Jonathan L. , Donahue Timothy R. , Morris Lilah F. , Bruhn Kevin W. , de la Rocha Pilar , Yang Meng-Yin , Mok Stephen , Garban Hermes J. , Craft Noah , Economou James S. , Marincola Francesco M. , Wang Ena , Ribas Antoni
Published: October 2009

Tumors grow in the presence of antigen-specific T cells, suggesting the existence of intrinsic cancer cell escape mechanisms. We hypothesized that a histone deacetylase (HDAC) inhibitor could sensitize tumor cells to immunotherapy because this class of agents has been reported to increase tumor antigen expression and shift gene expression to a proapoptotic milieu in cancer cells. To test this question, we treated B16 murine melanoma with the combination of the HDAC inhibitor LAQ824 and the adoptive transfer of gp100 melanoma antigen-specific pmel-1 T cells. The combined therapy significantly improved antitumor activity through several mechanisms: (a) increase in MHC and tumor-associated antigen expression by tumor cells; (b) decrease in competing endogenous lymphocytes in recipient mice, resulting in a proliferative advantage for the adoptively transferred cells; and (c) improvement in the functional activity of the adoptively transferred lymphocytes. We confirmed the beneficial effects of this HDAC inhibitor as a sensitizer to immunotherapy in a different model of prophylactic prime-boost vaccination with the melanoma antigen tyrosinase-related protein 2, which also showed a significant improvement in antitumor activity against B16 melanoma. In conclusion, the HDAC inhibitor LAQ824 significantly enhances tumor immunotherapy through effects on target tumor cells as well as improving the antitumor activity of tumor antigen-specific lymphocytes. [Cancer Res 2009;69(22):8693–9]
Metabolic Approaches to Treatment of Melanoma
Authors: Hersey Peter , Watts Ralph Neal , Zhang Xu Dong , Hackett John
Published: October 2009

Purpose: Lactate dehydrogenase (LDH) levels in blood of patients with melanoma have proven to be an accurate predictor of prognosis and response to some treatments. Exclusion of patients with high LDH levels from many trials of new treatments has created a need for treatments aimed at patients with high LDH levels. This article reviews the metabolic basis for the association of LDH with prognosis and the treatment initiatives that may be successful in this patient group.

Experimental Design: Review of current literature on the topic.

Results: A number of new treatment initiatives based on manipulation of metabolic pathways in melanoma cells are now available and await evaluation in well-designed clinical trials.

Conclusions: Different cancers may require different metabolic approaches for effective treatment. In view of the high rate of glycolysis in most melanoma cells, approaches based on inhibition of acid excretion from the cells seem particularly attractive. (Clin Cancer Res 2009;15(21):6490–4)