bluuebunny/crossref_metadata_2025 huggingface dataset:
Control-Oriented Modeling and Observer-Based Estimation of Solid and Gas Temperatures for a Diesel Engine Aftertreatment System
Authors: Chen Pingen , Wang Junmin
Published: September 2012

Diesel oxidation catalysts (DOCs) and diesel particulate filters (DPFs) have become standard components in diesel engine aftertreatment systems to remove carbon monoxide (CO), unburned hydrocarbon (HC), and particulate matter (PM) emissions. Many studies have been focused on improving the performances of DOCs and DPFs, which have been found to be influenced significantly by their respective thermal behaviors. The objective of this research is to develop a control-oriented thermal model for a DOC + DPF aftertreatment system. The control-oriented model is established by considering both thermal inertia of each component and chemical reactions inside it. Engine-out, DOC-out, and DPF-out emissions have been analyzed before simplified empirical models are proposed for the prediction of cared emission species. Experimental validation results show that the control-oriented models are capable of capturing both the gas phase and the solid phase thermal dynamics of a DOC and a DPF. An observer, designed based on the control-oriented solid temperature model and exhaust gas temperature model, can estimate the DOC and DPF gas and solid temperatures accurately in comparison with the measurements. The control-oriented thermal models and observer will be beneficial in the integrated engine and aftertreatment system control.
On Levitation and Lateral Control of Electromagnetic Suspension Maglev Systems
Authors: Aly Mohamed , Alberts Thomas
Published: September 2012

A study that compares between decentralized and centralized controllers for electromagnetic suspension (EMS) Maglev systems that use combined magnets with an inverted U-rail for levitation and lateral control is presented. A simple 2-DOF (degrees of freedom) Maglev system model (rigid and flexible body cases) that comprises heave and lateral modes is used. The study is based on two aspects. First, by sketching the multi-input multi-output (MIMO) root loci with every controller individually for system rigid and flexible body cases. Second, a gradient-like search algorithm based on an optimal criterion for decentralized and centralized controllers' gains tuning is used. The work is generalized on a real EMS Maglev system, and the simulation results for these Maglev systems shows that the centralized control is more capable of lateral displacements suppression that may result from disturbing lateral forces than the decentralized one.
Porous TEM windows fabrication using CsCl self-assembly
Authors: Liu Wenhan , Ferguson Mark , Yavuz Mustafa , Cui Bo
Published: September 2012

Thin non-porous silicon nitride membrane has been used for transmission electron microscopy (TEM) “windows” due to its transparency to high-energy electrons. However, to completely eliminate the background scattering, a porous membrane is desirable. Here the authors report the fabrication of porous silicon nitride membranes by CsCl self-assembly to form hemispherical islands, followed by “image reversal” via drying etching and liftoff steps. Through controlling the evaporated CsCl film thickness, the exposure time of the film in air, and the relative humidity of air, the authors were able to fabricate porous silicon nitride membranes with pore diameter and interpore spacing of order 100 nm. The pore diameter could be further shrunk by coating a conformal film onto the porous membrane. In addition, conductive porous TEM windows can be achieved by simply skipping the final metal removal step. Such a porous membrane would also find applications in separation or filtration of macromolecules or nanoparticles.
Interaction of Operational and Physicochemical Factors Leading to Gordonia amarae-Like Foaming in an Incompletely Nitrifying Activated Sludge Plant
Authors: Asvapathanagul Pitiporn , Huang Zhonghua , Gedalanga Phillip B. , Baylor Amber , Olson Betty H.
Published: September 2012

The overgrowth of
Gordonia amarae
-like bacteria in the mixed liquor of an incompletely nitrifying water reclamation plant was inversely correlated with temperature (
r
= −0.78;
P
< 0.005) and positively correlated with the solids retention time (SRT) obtained a week prior to sampling (
r
= 0.67;
P
< 0.005). Drops followed by spikes in the food-to-mass ratio (0.18 to 0.52) and biochemical oxygen demand concentrations in primary effluent (94 to 298 mg liter
−1
) occurred at the initiation of
G. amarae
-like bacterial growth. The total bacterial concentration did not increase as concentrations of
G. amarae
-like cells increased, but total bacterial cell concentrations fluctuated in a manner similar to that of
G. amarae
-like bacteria in the pseudo-steady state. The ammonium ion removal rate (percent) was inversely related to
G. amarae
-like cell concentrations during accelerated growth and washout phases. The dissolved oxygen concentration decreased as the
G. amarae
-like cell concentration decreased. The concentrations of
G. amarae
-like cells peaked (2.47 × 10
9
cells liter
−1
) approximately 1.5 months prior to foaming. Foaming occurred during the late pseudo-steady-state phase, when temperature declines reversed. These findings suggested that temperature changes triggered operational and physicochemical changes favorable to the growth of
G. amarae
-like bacteria. Fine-scale quantitative PCR (qPCR) monitoring at weekly intervals allowed a better understanding of the factors affecting this organism and indicated that frequent sampling was required to obtain statistical significance with factors changing as the concentrations of this organism increased. Furthermore, the early identification of
G. amarae
-like cells when they are confined to mixed liquor (10
7
cells liter
−1
) allows management strategies to prevent foaming.
Prevalence and Genetic Diversity of Bartonella spp. in Small Mammals from Southeastern Asia
Authors: Jiyipong Tawisa , Jittapalapong Sathaporn , Morand Serge , Raoult Didier , Rolain Jean-Marc
Published: September 2012

Among 1,341 blood samples from rodents that were trapped in Southeast Asia between 2008 and 2010, we found a prevalence of
Bartonella
infection ranging from 9.6 to 11.9%.
Bartonella
species identified (143 isolates) included
B. elizabethae
,
B. coopersplainsensis
,
B. phoceensis
,
B. queenslandensis
,
B. rattimassiliensis
,
B. tribocorum
, and three new putative
Bartonella
species.
Quantification of Bacterial Indicators and Zoonotic Pathogens in Dairy Wastewater Ponds
Authors: Dungan Robert S. , Klein Marcus , Leytem April B.
Published: September 2012

Zoonotic pathogens in land-applied dairy wastewaters are a potential health risk. The occurrence and abundance of 10 pathogens and 3 fecal indicators were determined by quantitative real-time PCR (qPCR) in samples from 30 dairy wastewaters from southern Idaho. Samples tested positive for
Campylobacter jejuni
,
stx
1
- and
eaeA
-positive
Escherichia coli
,
Listeria monocytogenes
,
Mycobacterium avium
subsp.
paratuberculosis
, and
Salmonella enterica
, with mean recoveries of genomic DNA corresponding to 10
2
to 10
4
cells ml
−1
wastewater. The most predominant organisms were
C. jejuni
and
M. avium
, being detected in samples from up to 21 and 29 of 30 wastewater ponds, respectively. The qPCR detection limits for the putative pathogens in the wastewaters ranged from 16 cells ml
−1
for
M. avium
to 1,689 oocysts ml
−1
for
Cryptosporidium. Cryptosporidium
and
Giardia
spp.,
Yersinia pseudotuberculosis
, and pathogenic
Leptospira
spp. were not detected by qPCR.
Stable Transfection of the Diplomonad Parasite Spironucleus salmonicida
Authors: Jerlström-Hultqvist Jon , Einarsson Elin , Svärd Staffan G.
Published: September 2012

Eukaryotic microbes are highly diverse, and many lineages remain poorly studied. One such lineage, the diplomonads, a group of binucleate heterotrophic flagellates, has been studied mainly due to the impact of
Giardia intestinalis
, an intestinal, diarrhea-causing parasite in humans and animals. Here we describe the development of a stable transfection system for use in
Spironucleus salmonicida
, a diplomonad that causes systemic spironucleosis in salmonid fish. We designed vectors in cassette format carrying epitope tags for localization (3×HA [where HA is hemagglutinin], 2×
Escherichia coli
OmpF linker and mouse langerin fusion sequence [2×OLLAS], 3×MYC) and purification of proteins (2× Strep-Tag II–FLAG tandem-affinity purification tag or streptavidin binding peptide–glutathione
S
-transferase [SBP-GST]) under the control of native or constitutive promoters. Three selectable gene markers, puromycin acetyltransferase (
pac
), blasticidin
S
-deaminase (
bsr
), and neomycin phosphotransferase (
nptII
), were successfully applied for the generation of stable transfectants. Site-specific integration on the
S. salmonicida
chromosome was shown to be possible using the
bsr
resistance gene. We epitope tagged six proteins and confirmed their expression by Western blotting. Next, we demonstrated the utility of these vectors by recording the subcellular localizations of the six proteins by laser scanning confocal microscopy. Finally, we described the creation of an
S. salmonicida
double transfectant suitable for colocalization studies. The transfection system described herein and the imminent completion of the
S. salmonicida
genome will make it possible to use comparative genomics as an investigative tool to explore specific, as well as general, diplomonad traits, benefiting research on both
Giardia
and
Spironucleu
s.
Transposon Mutagenesis Identifies Uropathogenic Escherichia coli Biofilm Factors
Authors: Hadjifrangiskou Maria , Gu Alice P. , Pinkner Jerome S. , Kostakioti Maria , Zhang Ellisa W. , Greene Sarah E. , Hultgren Scott J.
Published: September 2012

UropathogenicEscherichia coli(UPEC), which accounts for 85% of urinary tract infections (UTI), assembles biofilms in diverse environments, including the host. Besides forming biofilms on biotic surfaces and catheters, UPEC has evolved an intracellular pathogenic cascade that culminates in the formation of biofilm-like intracellular bacterial communities (IBCs) within bladder epithelial cells. Rapid bacterial replication during IBC formation augments a build-up in bacterial numbers and persistence within the host. Relatively little is known about factors mediating UPEC biofilm formation and how these overlap with IBC formation. To address this gap, we screened a UPEC transposon mutant library in threein vitrobiofilm conditions: Luria broth (LB)-polyvinyl chloride (PVC), YESCA (yeast extract-Casamino Acids)-PVC, and YESCA-pellicle that are dependent on type 1 pili (LB) and curli (YESCA), respectively. Flagella are important in all three conditions. Mutants were identified that had biofilm defects in all three conditions but had no significant effects on the expression of type 1 pili, curli, or flagella. Thus, this approach uncovered a comprehensive inventory of novel effectors and regulators that are involved in UPEC biofilm formation under multiple conditions. A subset of these mutants was found to be dramatically attenuated and unable to form IBCs in a murine model of UTI. Collectively, this study expands our insights into UPEC multicellular behavior that may provide insights into IBC formation and virulence.
Patterns of paediatric analgesic use in Africa: a systematic review
Authors: Madadi Parvaz , Enato Ehijie F O , Fulga Shir , Umeoduagu Chinonye C , MacLeod Stuart M , Koren Gideon , Einarson Thomas R
Published: September 2012

We conducted a systematic literature review with two objectives: (1) to assess reported patterns of analgesic use in African children and compare these observed patterns to the analgesics given in the WHO Essential Medicines List for Children (EMLc); and (2) to summarise outcomes related to effectiveness, adverse events, cost and accessibility of these analgesics. Eligible participants were children (≤12 years) living in any African country who received an analgesic administered with the intention of relieving pain in any setting. Thirty-four peer-reviewed, observational studies representing 7772 African children were accepted. Studies were conducted in 25 different regions of 12 countries. Pain was attributed to surgery, burns, sickle cell anaemia and conditions requiring palliation in 32% of children, and was unspecified in the other 68%. Of the three EMLc analgesics, paracetamol and ibuprofen were widely employed, constituting ∼60% of all analgesics, while morphine was used in 20 children (0.2%). There were 455 suspected adverse drug reactions which included 17 deaths. Analgesic use reported in African children appears to fall short of WHO standards.
Course setting and selected biomechanical variables related to injury risk in alpine ski racing: an explorative case study
Authors: Spörri Jörg , Kröll Josef , Schwameder Hermann , Schiefermüller Christian , Müller Erich
Published: September 2012

Background

Course setting has often been discussed as a potential preventative measure in the World Cup ski-racing community. However, there is limited understanding of how it is related to injury risk.

Objective

This study was undertaken to investigate the effect of increased horizontal gate distance on energy-related and injury mechanism-related variables.

Methods

During a video-based three-dimensional (3D)-kinematic field measurement, a top world-class racer performed giant slalom runs at two course settings with different horizontal gate distances. A full-body segment model was reconstructed in 3D and selected biomechanical parameters were calculated.

Results

For the analysed turn, no significant differences were found in turn speed for increased horizontal gate distance. However, a large effect size was observed for speed reduction towards the end of the turn. Turn forces were by tendency higher at the beginning and significantly higher towards the end of the turn. Additionally, significant differences were found in higher inward leaning, and large effect sizes were observed for a decreased fore/aft position after gate passage.

Conclusions

On the basis of the data of this study, no final conclusion can be made about whether, for a section of consecutive turns, increasing horizontal gate distance is an effective tool for speed reduction. However, this study pointed out two major drawbacks of this course setting modification: (1) it may increase fatigue as a consequence of loading forces acting over a longer duration; (2) it may increase the risk of out-of-balance situations by forcing the athlete to exhaust his backward and inward leaning spectrum.
Identifying early warning signs for diagnostic errors in primary care: a qualitative study
Authors: Balla John , Heneghan Carl , Goyder Clare , Thompson Matthew
Published: September 2012

Objective

We investigate the mechanisms of diagnostic error in primary care consultations to detect warning signs for possible error. We aim to identify places in the diagnostic reasoning process associated with major risk indicators.

Design

A qualitative study using semistructured interviews with open-ended questions.

Setting

A 2-month study in primary care conducted in Oxfordshire, UK.

Participants

We approached about 25 experienced general practitioners by email or word of mouth, 15 volunteered for the interviews and were available at a convenient time.

Intervention

Interview transcripts provided 45 cases of error. Three researchers searched these independently for underlying themes in relation to our conceptual framework.

Outcome measures

Locating steps in the diagnostic reasoning process associated with major risk of error and detecting warning signs that can alert clinicians to increased risk of error.

Results

Initiation and closure of the cognitive process are most exposed to risk of error. Cognitive biases developed early in the process lead to errors at the end. These warning signs can be used to alert clinicians to the increased risk of diagnostic error. Ignoring red flags or critical cues was related to processes being biased through the initial frame, but equally well, it could be explained by knowledge gaps.

Conclusions

Cognitive biases developed at the initial framing of the problem relate to errors at the end of the process. We refer to these biases as warning signs that can alert clinicians to the increased risk of diagnostic error. We conclude that lack of knowledge is likely to be an important factor in diagnostic error. Reducing diagnostic errors in primary care should focus on early and systematic recognition of errors including near misses, and a continuing professional development environment that promotes reflection in action to highlight possible causes of process bias and of knowledge gaps.
Maintaining momentum on welfare issues of dog breeding
Authors: Crispin Sheila
Published: September 2012

Sheila Crispin, chair of the Advisory Council on the Welfare Issues of Dog Breeding, discusses the work that the council has been undertaking since it was formed in 2010 and outlines some of its plans for the future.
ISOSPIN BREAKING IN PION COMPTON SCATTERING
Authors: KAISER N.
Published: September 2012

Using chiral perturbation theory we calculate for pion Compton scattering the isospin-breaking effects induced by the difference between the charged and neutral pion mass. At one-loop order this correction is directly proportional to [Formula: see text] and free of any contributions from short-distance electromagnetic counterterms. The differential cross-section for charged pion Compton scattering π-γ→π-γ gets affected (in backward directions) at the level of a few permille only. At the same time the isospin-breaking correction leads to a small shift of the pion polarizability difference by δ(απ-βπ)≃1.3⋅10-5 fm 3. In the case of the low-energy γγ→π0π0 reaction isospin breaking manifests itself through a cusp effect at the π+π- threshold. We give an improved estimate for this cusp effect using the empirical ππ-scattering length difference [Formula: see text].
ON INVARIANTS OF TOWERS OF FUNCTION FIELDS OVER FINITE FIELDS
Authors: HESS FLORIAN , STICHTENOTH HENNING , TUTDERE SEHER
Published: September 2012

In this paper, we consider a tower of function fields [Formula: see text] over a finite field 𝔽qand a finite extension E/F0such that the sequence [Formula: see text] is a tower over the field 𝔽q. Then we study invariants of [Formula: see text], that is, the asymptotic number of the places of degree r in [Formula: see text], for any r ≥ 1, if those of [Formula: see text] are known. We first give a method for constructing towers of function fields over any finite field 𝔽qwith finitely many prescribed invariants being positive. For q a square, we prove that with the same method one can also construct towers with at least one positive invariant and certain prescribed invariants being zero. Our method is based on explicit extensions. Moreover, we show the existence of towers over a finite field 𝔽qattaining the Drinfeld–Vladut bound of order r, for any r ≥ 1 with qra square (see [1, Problem-2]). Finally, we give some examples of non-optimal recursive towers with all but one invariants equal to zero.
NON-NORMAL GRAPHS OF FINITE GROUPS
Authors: FARROKHI D. G. M. , ERFANIAN A. , TOLUE B.
Published: September 2012

Let G be a finite group and H be a subgroup of G. We introduce the non-normal graph of H in G, denoted by [Formula: see text]H,G, and give some of the graph theoretical properties of [Formula: see text]H,G.
FINITE GROUPS WITH NON-CYCLIC 2-SUBGROUPS WHICH ARE SUBNORMAL OR HAVE SMALL INDICES IN THEIR NORMALIZERS
Authors: SHI JIANGTAO , ZHANG CUI
Published: September 2012

A new criteria for the solvability of finite groups is obtained. It is proven that a finite group G is always solvable if

(i) H is subnormal in G or |NG(H) : H| ≤ 2 for every non-cyclic 2-subgroup H of G that is not a subgroup of Z(G), or

(ii) H is subnormal in G or G is A4-free and |NG(H) : H| ≤ 6 for every non-cyclic 2-subgroup H of G that is not a subgroup of Z(G).

Moreover, some new criteria for a finite group being p-nilpotent are also obtained.
REPRESENTING FILIFORM LIE ALGEBRAS MINIMALLY AND FAITHFULLY BY STRICTLY UPPER-TRIANGULAR MATRICES
Authors: CEBALLOS MANUEL , NÚÑEZ JUAN , TENORIO ÁNGEL F.
Published: September 2012

In this paper, we compute minimal faithful representations of filiform Lie algebras by means of strictly upper-triangular matrices. To obtain such representations, we use nilpotent Lie algebras [Formula: see text]n, of n × n strictly upper-triangular matrices, because any given (filiform) nilpotent Lie algebra [Formula: see text] admits a Lie-algebra isomorphism with a subalgebra of [Formula: see text]n for some n ∈ ℕ\{1}. In this sense, we search for the lowest natural integer n such that the Lie algebra [Formula: see text]n contains the filiform Lie algebra [Formula: see text] as a subalgebra. Additionally, we give a representative of each representation.
THE INTERSECTION GRAPH OF GAMMA SETS IN THE TOTAL GRAPH OF A COMMUTATIVE RING-I
Authors: CHELVAM T. TAMIZH , ASIR T.
Published: September 2012

Let R be a commutative ring and Z(R) be its set of all zero-divisors. Anderson and Badawi [The total graph of a commutative ring, J. Algebra320 (2008) 2706–2719] introduced the total graph of R, denoted by TΓ(R), as the undirected graph with vertex set R, and two distinct vertices x and y are adjacent if and only if x + y ∈ Z(R). Tamizh Chelvam and Asir [Domination in the total graph of a commutative ring, to appear in J. Combin. Math. Combin. Comput.] obtained the domination number of the total graph and studied certain other domination parameters of TΓ(R) where R is a commutative Artin ring. The intersection graph of gamma sets in TΓ(R) is denoted by ITΓ(R). Tamizh Chelvam and Asir [Intersection graph of gamma sets in the total graph, Discuss. Math. Graph Theory32 (2012) 339–354, doi:10.7151/dmgt.1611] initiated a study about the intersection graph ITΓ (ℤn) of gamma sets in TΓ(ℤn). In this paper, we study about ITΓ(R), where R is a commutative Artin ring. Actually we investigate the interplay between graph-theoretic properties of ITΓ(R) and ring-theoretic properties of R. At the first instance, we prove that diam (ITΓ(R)) ≤ 2 and gr (ITΓ(R)) ≤ 4. Also some characterization results regarding completeness, bipartite, cycle and chordal nature of ITΓ(R) are given. Further, we discuss about the vertex-transitive property of ITΓ(R). At last, we obtain all commutative Artin rings R for which ITΓ(R) is either planar or toroidal or genus two.
ON INTERRELATIONS BETWEEN FUZZY CONGRUENCE AXIOMS
Authors: CHAUDHARI S. R. , DESAI S. S.
Published: September 2012

In this paper we establish interrelations between fuzzy direct revelation axiom (FDRA), fuzzy transitive-closure coherence axiom (FTCCA), fuzzy consistent-closure coherence axiom (FCCCA) and fuzzy intermediate congruence axiom (FICA). We also establish their relationships with weak fuzzy congruence axiom (WFCA), strong fuzzy congruence axiom (SFCA) and weak axiom of fuzzy revealed preference (WAFRP). Condition for equivalence of fuzzy Arrow axiom (FAA) and weak fuzzy congruence axiom (WFCA) on arbitrary domain is also given.
ON k-BI-IDEALS IN HEMIRINGS
Authors: SHABIR MUHAMMAD , ANJUM RUKHSHANDA
Published: September 2012

In this paper we define prime, strongly prime and semiprime k-bi-ideals of a hemiring. We also define their fuzzy versions and characterize hemirings by the properties of these k-bi-ideals.
VOLTAGE DRIVEN NONDESTRUCTIVE SELF-REFERENCE SENSING FOR STT-RAM YIELD ENHANCEMENT
Authors: LI HAI (HELEN) , SUN ZHENYU
Published: September 2012

Spin-transfer torque random access memory (STT-RAM) has demonstrated great potentials as a universal memory for its fast access speed, zero standby power, excellent scalability and simplicity of cell structure. However, large process variations of both magnetic tunneling junction and CMOS process severely limit the yield of STT-RAM chips. In this paper, we propose a novel voltage-driven non-destructive self-reference sensing scheme (NDRS) to enhance the STT-RAM chip yield by significantly improving sense margin. Monte-Carlo simulations of a 16 Kb STT-RAM array shows that our proposed scheme can achieve the same yield as the previous NDRS scheme while improving the sense margin by 5 × with the similar access performance and power.
RADIO FREQUENCY MAGNETIZATION NONVOLATILITY
Authors: WANG XIAOBIN
Published: September 2012

Long time magnetization thermal switching under small amplitude high frequency excitation is analyzed. Approaches based upon conventional time-dependent energy barrier are not sufficient to describe magnetization nonvolatility under GHz excitations. Methods based upon large angle nonlinear magnetization dynamics are developed for both coherent and noncoherent magnetization switching. This dynamic approach is not only important for fundamental understanding of magnetization dynamics under combined radio frequency excitations and thermal fluctuations, but also critical for practical design of emerging spintronic devices. When applied to spin torque random access memory read operations, as sensing current duration reaches nanosecond, dynamic approach gives a switching probability estimation orders of magnitude different from that obtained from conventional time-dependent energy barrier approach.
Probing Mechanisms That Underlie Human Neurodegenerative Diseases in Drosophila
Authors: Jaiswal M. , Sandoval H. , Zhang K. , Bayat V. , Bellen H.J.
Published: September 2012

The fruit fly, Drosophila melanogaster, is an excellent organism for the study of the genetic and molecular basis of metazoan development. Drosophila provides numerous tools and reagents to unravel the molecular and cellular functions of genes that cause human disease, and the past decade has witnessed a significant expansion of the study of neurodegenerative disease mechanisms in flies. Here we review the interplay between oxidative stress and neuronal toxicity. We cover some of the studies that show how proteasome degradation of protein aggregates, autophagy, mitophagy, and lysosomal function affect the quality control mechanisms required for neuronal survival. We discuss how forward genetic screens in flies have led to the isolation of a few loci that cause neurodegeneration, paving the way for large-scale systematic screens to identify such loci in flies as well as promoting gene discovery in humans.
High-Frequency Radar Observations of Ocean Surface Currents
Authors: Paduan Jeffrey D. , Washburn Libe
Published: September 2012

This article reviews the discovery, development, and use of high-frequency (HF) radio wave backscatter in oceanography. HF radars, as the instruments are commonly called, remotely measure ocean surface currents by exploiting a Bragg resonant backscatter phenomenon. Electromagnetic waves in the HF band (3–30 MHz) have wavelengths that are commensurate with wind-driven gravity waves on the ocean surface; the ocean waves whose wavelengths are exactly half as long as those of the broadcast radio waves are responsible for the resonant backscatter. Networks of HF radar systems are capable of mapping surface currents hourly out to ranges approaching 200 km with a horizontal resolution of a few kilometers. Such information has many uses, including search and rescue support and oil-spill mitigation in real time and larval population connectivity assessment when viewed over many years. Today, HF radar networks form the backbone of many ocean observing systems, and the data are assimilated into ocean circulation models.
The Oligotrophic Ocean Is Heterotrophic
Authors: Duarte Carlos M. , Regaudie-de-Gioux Aurore , Arrieta Jesús M. , Delgado-Huertas Antonio , Agustí Susana
Published: September 2012

Incubation (in vitro) and incubation-free (in situ) methods, each with their own advantages and limitations, have been used to derive estimates of net community metabolism in the oligotrophic subtropical gyres of the open ocean. The hypothesis that heterotrophic communities are prevalent in most oligotrophic regions is consistent with the available evidence and supported by scaling relationships showing that heterotrophic communities prevail in areas of low gross primary production, low chlorophyll a, and warm water, conditions found in the oligotrophic ocean. Heterotrophic metabolism can prevail where heterotrophic activity is subsidized by organic carbon inputs from the continental shelf or the atmosphere and from nonphotosynthetic autotrophic and mixotrophic metabolic pathways. The growth of the oli-gotrophic regions is likely to be tilting the metabolic balance of the ocean toward a greater prevalence of heterotrophic communities.
Chromosome Translocation, B Cell Lymphoma, and Activation-Induced Cytidine Deaminase
Authors: Robbiani Davide F. , Nussenzweig Michel C.
Published: September 2012

Studies of B cell lymphomas in the early 1980s led to the cloning of genes (c-MYC and IGH) at a chromosome translocation breakpoint. A rush followed to identify recurrently translocated genes in all types of cancer, which led to remarkable advances in our understanding of cancer genetics. B lymphocyte tumors commonly bear chromosome translocations to immunoglobulin genes, which points to a role for antibody gene diversification processes in tumorigenesis. The discovery of activation-induced cytidine deaminase (AID) and the use of murine models to study translocation have led to a new understanding of how these events contribute to the genesis of lymphomas. Here, we review these advances with a focus on AID and insights gained from the study of translocations in primary cells.
Cross talk betweenS-nitrosylation andS-glutathionylation in control of the Na,K-ATPase regulation in hypoxic heart
Authors: Yakushev Sergej , Band Mark , Tissot van Patot Martha C. , Gassmann Max , Avivi Aaron , Bogdanova Anna
Published: September 2012

Oxygen-induced regulation of Na,K-ATPase was studied in rat myocardium. In rat heart, Na,K-ATPase responded to hypoxia with a dose-dependent inhibition in hydrolytic activity. Inhibition of Na,K-ATPase in hypoxic rat heart was associated with decrease in nitric oxide (NO) production and progressive oxidative stress. Accumulation of oxidized glutathione (GSSG) and decrease in NO availability in hypoxic rat heart were followed by a decrease in S-nitrosylation and upregulation of S-glutathionylation of the catalytic α-subunit of the Na,K-ATPase. Induction of S-glutathionylation of the α-subunit by treatment of tissue homogenate with GSSG resulted in complete inhibition of the enzyme in rat a myocardial tissue homogenate. Inhibitory effect of GSSG in rat sarcolemma could be significantly decreased upon activation of NO synthases. We have further tested whether oxidative stress and suppression of the Na,K-ATPase activity are observed in hypoxic heart of two subterranean hypoxia-tolerant blind mole species ( Spalax galili and Spalax judaei). In both hypoxia-tolerant Spalax species activity of the enzyme and tissue redox state were maintained under hypoxic conditions. However, localization of cysteines within the catalytic subunit of the Na,K-ATPase was preserved and induction of S-glutathionylation by GSSG in tissue homogenate inhibited the Spalax ATPase as efficiently as in rat heart. The obtained data indicate that oxygen-induced regulation of the Na,K-ATPase in the heart is mediated by a switch between S-glutathionylation and S-nitrosylation of the regulatory thiol groups localized at the catalytic subunit of the enzyme.
Cigarette smoke and its component acrolein augment IL-8/CXCL8 mRNA stability via p38 MAPK/MK2 signaling in human pulmonary cells
Authors: Moretto Nadia , Bertolini Serena , Iadicicco Claudia , Marchini Gessica , Kaur Manminder , Volpi Giorgia , Patacchini Riccardo , Singh Dave , Facchinetti Fabrizio
Published: September 2012

Interleukin-8 (IL-8/CXCL8) is an important neutrophil chemoattractant known to be elevated in the airways of cigarette smokers and in patients with chronic obstructive pulmonary disease (COPD). We examined the acute effect of aqueous cigarette smoke extract (CSE) on IL-8 expression in primary human pulmonary cells, in particular in normal human bronchial smooth muscle cells (HBSMCs). IL-8 mRNA levels increased upon CSE exposure in a concentration- and time-dependent manner, and such an effect was accompanied by IL-8 secretion. CSE-evoked elevation of IL-8 mRNA was mimicked by its component acrolein. Both CSE and acrolein induced p38 mitogen-activated protein kinase (MAPK) phosphorylation, accompanied by the phosphorylation of MAPK-activated kinase 2 (MK2), a known downstream substrate of the p38 MAPK, both in HBSMCs and in human airway epithelial cells. Furthermore, pharmacological inhibition of p38 MAPK or MK2 strongly accelerated the decay of IL-8 mRNA levels upon stimulation with CSE or acrolein and subsequent blockade of mRNA neosynthesis with actinomycin D in pulmonary structural cells (HBSMCs and airways epithelial cells) as well as in human alveolar macrophages. Conversely, pharmacological inhibition of ERK1/2 signaling inhibited CSE-induced steady-state levels of IL-8 mRNA without affecting mRNA stability, thus suggesting inhibition at the transcriptional level. In sum, p38 MAPK/MK2 signaling is an important posttranscriptional mechanism underlying upregulation of IL-8 mRNA levels elicited by CSE and acrolein. Given the pivotal role of IL-8 in neutrophil chemotaxis and activation, our results shed light on the mechanisms through which cigarette smoke can initiate inflammation in the lung.
Role of TNFR1 in the innate airway hyperresponsiveness of obese mice
Authors: Zhu Ming , Williams Alison S. , Chen Lucas , Wurmbrand Allison P. , Williams Erin S. , Shore Stephanie A.
Published: September 2012

The purpose of this study was to examine the role of tumor necrosis factor receptor 1 (TNFR1) in the airway hyperresponsiveness characteristic of obese mice. Airway responsiveness to intravenous methacholine was measured using the forced oscillation technique in obese Cpefatmice that were either sufficient or genetically deficient in TNFR1 ( Cpefatand Cpefat/TNFR1−/−mice) and in lean mice that were either sufficient or genetically deficient in TNFR1 [wild-type (WT) and TNFR1−/−mice]. Compared with lean WT mice, Cpefatmice exhibited airway hyperresponsiveness. Airway hyperresponsives was also greater in Cpefat/TNFR1−/−than in Cpefatmice. Compared with WT mice, Cpefatmice had increases in bronchoalveolar lavage fluid concentrations of several inflammatory moieties including eotaxin, IL-9, IP-10, KC, MIG, and VEGF. These factors were also significantly elevated in Cpefat/TNFR1−/−vs. TNFR1−/−mice. Additional moieties including IL-13 were also elevated in Cpefat/TNFR1−/−vs. TNFR1−/−mice but not in Cpefatvs. WT mice. IL-17A mRNA expression was greater in Cpefat/TNFR1−/−vs. Cpefatmice and in TNFR1−/−vs. WT mice. Analysis of serum indicated that obesity resulted in systemic as well as pulmonary inflammation, but TNFR1 deficiency had little effect on this systemic inflammation. Our results indicate that TNFR1 is protective against the airway hyperresponsiveness associated with obesity and suggest that effects on pulmonary inflammation may be contributing to this protection.
Heterogeneous atrophy occurs within individual lower limb muscles during 60 days of bed rest
Authors: Miokovic Tanja , Armbrecht Gabriele , Felsenberg Dieter , Belavý Daniel L.
Published: September 2012

To better understand disuse muscle atrophy, via magnetic resonance imaging, we sequentially measured muscle cross-sectional area along the entire length of all individual muscles from the hip to ankle in nine male subjects participating in 60-day head-down tilt bed rest (2nd Berlin BedRest Study; BBR2–2). We hypothesized that individual muscles would not atrophy uniformly along their length such that different regions of an individual muscle would atrophy to different extents. This hypothesis was confirmed for the adductor magnus, vasti, lateral hamstrings, medial hamstrings, rectus femoris, medial gastrocnemius, lateral gastrocnemius, tibialis posterior, flexor hallucis longus, flexor digitorum longus, peroneals, and tibialis anterior muscles ( P ≤ 0.004). In contrast, the hypothesis was not confirmed in the soleus, adductor brevis, gracilis, pectineus, and extensor digitorum longus muscles ( P ≥ 0.20). The extent of atrophy only weakly correlated ( r = −0.30, P < 0.001) with the location of greatest cross-sectional area. The rate of atrophy during bed rest also differed between muscles ( P < 0.0001) and between some synergists. Most muscles recovered to their baseline size between 14 and 90 days after bed rest, but flexor hallucis longus, flexor digitorum longus, and lateral gastrocnemius required longer than 90 days before recovery occurred. On the basis of findings of differential atrophy between muscles and evidence in the literature, we interpret our findings of intramuscular atrophy to reflect differential disuse of functionally different muscle regions. The current work represents the first lower-limb wide survey of intramuscular differences in disuse atrophy. We conclude that intramuscular differential atrophy occurs in most, but not all, of the muscles of the lower limb during prolonged bed rest.
Predictors of Survival in Never-Smokers with Non–Small Cell Lung Cancer: A Large-Scale, Two-Phase Genetic Study
Authors: Pu Xia , Ye Yuanqing , Spitz Margaret R. , Wang Liang , Gu Jian , Lippman Scott M. , Hildebrandt Michelle A.T. , Hong Waun Ki , Minna John D. , Roth Jack A. , Yang Ping , Wu Xifeng
Published: September 2012

Purpose: Lung cancer in never-smokers (LCINS) is increasingly recognized as a distinct disease from that in ever-smokers owing to substantial differences in etiology, clinical characteristics, and prognosis. Therefore, we aimed to identify prognostic markers specific for LCINS.

Experimental Design: First, 11,930 single-nucleotide polymorphisms (SNP) in 904 inflammation-related genes were genotyped, and their associations with overall survival in 411 patients with LCINS at MD Anderson Cancer Center were analyzed. Next, validation of the top 27 SNPs in 311 patients with LCINS at Mayo Clinic was conducted.

Results: Three SNPs (IL17RA:rs879576, BMP8A:rs698141, and STY:rs290229) were validated (P < 0.05), and two SNPs (CD74:rs1056400 and CD38:rs10805347) reached borderline significance (P = 0.08) in the Mayo Clinic population. We validated a survival-tree created in the MD Anderson population exploring gene–gene interactions in the Mayo Clinic population. This survival-tree stratified patients into subsets with significantly different risks of death: patients with the rs1056400_GG/rs698141_GA + AA genotype had significantly higher risk of death in both MD Anderson (HR:2.32, 95%CI: 1.58–3.41) and Mayo (HR:1.97, 95%CI: 1.11–3.50) populations compared with those with the rs1056400_GG/rs698141_GG or rs1056400_GA + AA genotype. We evaluated these five SNPs in 996 ever-smokers from MD Anderson and found no significant associations.

Conclusions: Our study provides strong evidence that inflammation-related genetic variations can affect clinical outcomes in LCINS, which may lead to significant biologic insight into these outcomes. Clin Cancer Res; 18(21); 5983–91. ©2012 AACR.
Genotype-Dependent Impairment of Hemoglobin Clearance Increases Oxidative and Inflammatory Response in Human Diabetic Atherosclerosis
Authors: Purushothaman Meerarani , Krishnan Prakash , Purushothaman K-Raman , Baber Usman , Tarricone Arthur , Perez Juan S. , Wiley Jose , Kini Annapoorna , Sharma Samin K. , Fuster Valentin , Moreno Pedro R.
Published: September 2012

Objective—

Haptoglobin (Hp) protein is responsible for hemoglobin clearance after intra-plaque hemorrhage. Hp gene exists as Hp-1 and Hp-2 alleles and the phenotypes show important molecular heterogeneity. We tested the hypothesis that hemoglobin clearance may be deficient in diabetic atheroma from patients with Hp2-2, triggering increased oxidative, inflammatory, and angiogenic patterns compared with controls.

Methods and Results—

Forty patients with diabetes mellitus were genotyped and their peripheral plaques compared after atherectomy. Plaque hemorrhage, iron content, hemoglobin-binding protein CD163, and heme-oxygenase-1 were quantified. Oxidative, inflammatory, and angiogenic patterns were evaluated by measuring myeloperoxidase, interleukin-10, macrophages, vascular cell adhesion molecule-1, smooth muscle actin, and plaque neovascularization (CD34/CD31). Plaques with Hp2-2 (n=7) had increased hemorrhage (
P
<0.005), iron content (
P
<0.001), and reduced CD163 expression (
P
<0.002) compared with controls (n=14). Hp2-2 plaques had increased heme-oxygenase-1 protein (
P
<0.02), myeloperoxidase gene (
P
<0.05), and protein (
P
<0.0001). Anti-inflammatory interleukin-10 gene (
P
<0.04), and protein expressions (
P
<0.0001) were decreased in Hp2-2. Finally, macrophage (
P
<0.0001), vascular cell adhesion molecule-1 (
P
=0.001), smooth muscle actin (
P
=0.002) scores, and neovessels density (
P
<0.0001) were increased in Hp2-2.

Conclusion—

Genotype-dependent impairment of hemoglobin clearance after intra-plaque hemorrhage is associated with increased oxidative, inflammatory, and angiogenic response in human diabetic atherosclerosis.
Novel Role of HAX-1 in Ischemic Injury Protection Involvement of Heat Shock Protein 90
Authors: Lam Chi Keung , Zhao Wen , Cai Wenfeng , Vafiadaki Elizabeth , Florea Stela M. , Ren Xiaoping , Liu Yong , Robbins Nathan , Zhang Zhiguo , Zhou Xiaoyang , Jiang Min , Rubinstein Jack , Jones W. Keith , Kranias Evangelia G.
Published: September 2012

Rationale:

Ischemic heart disease is characterized by contractile dysfunction and increased cardiomyocyte death, induced by necrosis and apoptosis. Increased cell survival after an ischemic insult is critical and depends on several cellular pathways, which have not been fully elucidated.

Objective:

To test the hypothesis that the anti-apoptotic hematopoietic lineage substrate-1–associated protein X-1 (HAX-1), recently identified as regulator of cardiac Ca cycling, also may ameliorate cellular injury with an ischemic insult.

Methods and Results:

We report that cardiac ischemia/reperfusion injury is associated with significant decreases in HAX-1 levels ex vivo and in vivo. Accordingly, overexpression of HAX-1 improved contractile recovery, coupled with reduced infarct size, plasma troponin I level, and apoptosis. The beneficial effects were associated with decreased endoplasmic reticulum (ER) stress response through specific inhibition of the inositol-requiring enzyme (IRE-1) signaling pathway, including its downstream effectors caspase-12 and the transcription factor C/EBP homologous protein. Conversely, HAX-1 heterozygous-deficient hearts exhibited increases in infarct size and IRE-1 activity. The inhibitory effects of HAX-1 were mediated by its binding to the N-terminal fragment of the heat shock protein 90 (Hsp90). Moreover, HAX-1 sequestered Hsp90 from IRE-1 to the phospholamban–sarcoplasmic/endoplasmic reticulum calcium ATPase complex. The HAX-1 regulation was further supported by loss of IRE-1 inhibition in presence of the Hsp90 inhibitor, 17-N-allylamino-17-demethoxygeldanamycin.

Conclusions:

Cardiac ischemia-reperfusion injury is associated with decreases in HAX-1 levels. Consequently, overexpression of HAX-1 promotes cardiomyocyte survival, mediated by its interaction with Hsp90 and specific inhibition of IRE-1 signaling at the ER/sarcoplasmic reticulum.
Associations Among Vascular Risk Factors, Carotid Atherosclerosis, and Cortical Volume and Thickness in Older Adults
Authors: Cardenas Valerie A. , Reed Bruce , Chao Linda L. , Chui Helena , Sanossian Nerses , DeCarli Charles C. , Mack Wendy , Kramer Joel , Hodis Howard N. , Yan Mingzhu , Buonocore Michael H. , Carmichael Owen , Jagust William J. , Weiner Michael W.
Published: September 2012

Background and Purpose—

The purpose of this study was to investigate whether the Framingham Cardiovascular Risk Profile and carotid artery intima-media thickness are associated with cortical volume and thickness.

Methods—

Consecutive subjects participating in a prospective cohort study of aging and mild cognitive impairment enriched for vascular risk factors for atherosclerosis underwent structural MRI scans at 3-T and 4-T MRI at 3 sites. Freesurfer (Version 5.1) was used to obtain regional measures of neocortical volumes (mm
3
) and thickness (mm). Multiple linear regression was used to determine the association of Framingham Cardiovascular Risk Profile and carotid artery intima-media thickness with cortical volume and thickness.

Results—

One hundred fifty-two subjects (82 men) were aged 78 (±7) years, 94 had a clinical dementia rating of 0, 58 had a clinical dementia rating of 0.5, and the mean Mini-Mental State Examination was 28 ± 2. Framingham Cardiovascular Risk Profile score was inversely associated with total gray matter volume and parietal and temporal gray matter volume (adjusted
P
<0.04). Framingham Cardiovascular Risk Profile was inversely associated with parietal and total cerebral gray matter thickness (adjusted
P
<0.03). Carotid artery ntima-media thickness was inversely associated with thickness of parietal gray matter only (adjusted
P
=0.04). Including history of myocardial infarction or stroke and radiological evidence of brain infarction, or apolipoprotein E genotype did not alter relationships with Framingham Cardiovascular Risk Profile or carotid artery intima-media thickness.

Conclusions—

Increased cardiovascular risk was associated with reduced gray matter volume and thickness in regions also affected by Alzheimer disease independent of infarcts and apolipoprotein E genotype. These results suggest a “double hit” toward developing dementia when someone with incipient Alzheimer disease also has high cardiovascular risk.
What Causes Disability After Transient Ischemic Attack and Minor Stroke?
Authors: Coutts Shelagh B. , Modi Jayesh , Patel Shiel K. , Aram Heidi , Demchuk Andrew M. , Goyal Mayank , Hill Michael D.
Published: September 2012

Background and Purpose—

Minor stroke and transient ischemic attack portend a significant risk of disability. Three possible mechanisms for this include disability not captured by the National Institutes of Health Stroke Scale, symptom progression, or recurrent stroke. We sought to assess the relative impact of these mechanisms on disability in a population of patients with transient ischemic attack and minor stroke.

Methods—

Five hundred ten consecutive minor stroke (National Institutes of Health Stroke Scale <4) or patients with transient ischemic attack who were previously not disabled and had a CT/CT angiography completed within 24 hours of symptom onset were prospectively enrolled. Disability was assessed at 90 days using the modified Rankin Scale. Predictors of disability (modified Rankin Scale ≥2) and the relative impact of the initial event versus recurrent events were assessed.

Results—

Seventy-four of 499 (15%; 95% CI, 12%–18%) patients had a disabled outcome. Baseline factors predicting disability were: age ≥60 years, diabetes mellitus, premorbid modified Rankin Scale 1, ongoing symptoms, baseline National Institutes of Health Stroke Scale, CT/CT angiography-positive metric, and diffusion-weighted imaging positivity. In the multivariable analysis ongoing symptoms (OR, 2.4; 95% CI, 1.3–4.4;
P
=0.004), diabetes mellitus (OR, 2.3; 95% CI, 1.2–4.3;
P
=0.009), female sex (OR, 1.8; 95% CI, 1.1–3;
P
=0.025), and CT/CT angiography-positive metric (OR, 2.4; 95% CI, 1.4–4;
P
=0.001) predicted disability. Of the 463 patients who did not have a recurrent event, 55 were disabled (12%). By contrast 19 of 36 (53%) patients were disabled after a recurrent event (risk ratio, 4.4; 95% CI, 3–6.6;
P
<0.0001).

Conclusions—

We found that a substantial proportion of patients with transient ischemic attack and minor stroke become disabled. In terms of absolute numbers, most patients have disability as a result of their presenting event; however, recurrent events have the largest relative impact on outcome.