bluuebunny/crossref_metadata_2025 huggingface dataset:
Disparities in Neighborhood Food Environments: Implications of Measurement Strategies
Authors: Bader Michael D. M. , Purciel Marnie , Yousefzadeh Paulette , Neckerman Kathryn M.
Published: September 2010

abstract

Public health researchers have begun to map the neighborhood “food environment” and examine its association with the risk of overweight and obesity. Some argue that “food deserts”—areas with little or no provision of fresh produce and other healthy food—may contribute to disparities in obesity, diabetes, and related health problems. While research on neighborhood food environments has taken advantage of more technically sophisticated ways to assess distance and density, in general, it has not considered how individual or neighborhood conditions might modify physical distance and thereby affect patterns of spatial accessibility. This study carried out a series of sensitivity analyses to illustrate the effects on the measurement of disparities in food environments of adjusting for cross‐neighborhood variation in vehicle ownership rates, public transit access, and impediments to pedestrian travel, such as crime and poor traffic safety. The analysis used geographic information systems data for New York City supermarkets, fruit and vegetable markets, and farmers' markets and employed both kernel density and distance measures. We found that adjusting for vehicle ownership and crime tended to increase measured disparities in access to supermarkets by neighborhood race/ethnicity and income, while adjusting for public transit and traffic safety tended to narrow these disparities. Further, considering fruit and vegetable markets and farmers' markets, as well as supermarkets, increased the density of healthy food outlets, especially in neighborhoods with high concentrations of Hispanics, Asians, and foreign‐born residents and in high‐poverty neighborhoods.
On the Background and Motivation of Students in a Beginning Spanish Program
Authors: Mandell Paul B.
Published: September 2010

ABSTRACT: A number of recent articles have examined the motivation, purpose of study, and demographics of first‐ and second‐year language learners of French or Spanish (see, e.g., Ossipov, 2000; Rava, 2000; Voght, 2000; Wen, 1997) This study surveyed the make‐up of a sample of first‐and second‐year university‐level Spanish learners at a major postsecondary institution in a city with a substantial, growing population of monolingual and bilingual Spanish speakers. The results of the survey were used to address questions about learner preparation prior to entering a four‐year university course of study, preferred and desired activities in the current curriculum, and motivations for the study of Spanish. Generalizations about the nature of the typical learner in this context and the implications of the appreciation of and desire for grammar‐related and communicative activities — as expressed by the respondents — in the contemporary liberal arts curriculum are discussed.
Steinheim suevite—A first report of melt‐bearing impactites from the Steinheim Basin (SW Germany)
Authors: BUCHNER Elmar , SCHMIEDER Martin
Published: September 2010

Abstract– The 3.8 km Steinheim Basin in SW Germany is a complex impact crater with central uplift hosted by a sequence of Triassic to Jurassic sedimentary rocks. It exhibits a well‐preserved crater morphology, intensely brecciated limestone blocks that form the crater rim, as well as distinct shatter cones in limestones. In addition, an impact breccia mainly composed of Middle to Upper Jurassic limestones, marls, mudstones, and sandstones is known from drilling into the impact crater. No impact melt lithologies, however, have so far been reported from the Steinheim Basin. In samples of the breccia that were taken from the B‐26 drill core, we discovered small particles (up to millimeters in size) that are rich in SiO2 (∼50 wt%) and Al2O3 (∼28 wt%), and contain particles of Fe‐Ni‐Co sulfides, as well as target rock clasts (shocked and unshocked quartz, feldspar, limestone) and droplet‐shaped particles of calcite. The particles exhibit distinct flow structures and relicts of schlieren and vesicles. From the geochemical composition and the textural properties, we interpret these particles as mixed silicate melt fragments widely recrystallized, altered, and/or transformed into hydrous phyllosilicates. Furthermore, we detected schlieren of lechatelierite and recrystallized carbonate melt. On the basis of impactite nomenclature, the melt‐bearing impact breccia in the Steinheim Basin can be denominated as Steinheim suevite. The geochemical character of the mixed melt particles points to Middle Jurassic sandstones (“Eisensandstein” Formation) that crop out at the center of the central uplift as the source for the melt fragments.
An RpoB Mutation Confers Dual Heteroresistance to Daptomycin and Vancomycin in
Staphylococcus aureus
Authors: Cui Longzhu , Isii Taisuke , Fukuda Minoru , Ochiai Tomonori , Neoh Hui-min , Camargo Ilana Lopes Baratella da Cunha , Watanabe Yukiko , Shoji Mitsutaka , Hishinuma Tomomi , Hiramatsu Keiichi
Published: September 2010

We have previously reported the establishment of a
Staphylococcus aureus
laboratory strain, 10*3d1, having reduced susceptibility to daptomycin and heterogeneous vancomycin-intermediate
S. aureus
(VISA) phenotype. The strain was generated
in vitro
by serial daptomycin selection (Camargo, I. L., H. M. Neoh, L. Cui, and K. Hiramatsu, Antimicrob. Agents Chemother. 52:4289-4299, 2008). Here we explored the genetic mechanism of resistance in the strain by whole-genome sequencing and by producing gene-replaced strains. By genome comparison between 10*3d1 and its parent methicillin-resistant
Staphylococcus aureus
(MRSA) strain N315ΔIP, we identified five nonsynonymous single nucleotide polymorphisms (SNPs). One of the five mutations was found in the
rpoB
gene encoding the RNA polymerase β subunit. The mutation at nucleotide position 1862 substituted the 621st alanine by glutamic acid. The replacement of the intact
rpoB
with the mutated
rpoB
, designated
rpoB(A621E)
, conferred N315ΔIP with the phenotypes of reduced susceptibility to daptomycin and hetero-VISA. The
rpoB(A621E)
-mediated resistance conversion was accompanied by a thickened cell wall and reduction of the cell surface negative charge. Being consistent with these phenotypic changes, microarray data showed that the expression of the
dlt
operon, which increases the cell surface positive charge, was enhanced in the
rpoB(A621E)
mutant. Other remarkable findings of microarray analysis of the
rpoB(A621E)
mutant included repression of metabolic pathways of purine, pyrimidine, arginine, the urea cycle, and the
lac
operon, enhancement of the biosynthetic pathway of vitamin B2, K1, and K2, and cell wall metabolism. Finally, mutations identified in
rplV
and
rplC
, encoding 50S ribosomal proteins L22 and L3, respectively, were found to be associated with the slow growth, but not with the phenotype of decreased susceptibility to vancomycin and daptomycin, of 10*3d1.
Structure-Activity Relationships of Diverse Oxazolidinones for Linezolid-Resistant
Staphylococcus aureus
Strains Possessing the
cfr
Methyltransferase Gene or Ribosomal Mutations
Authors: Locke Jeffrey B. , Finn John , Hilgers Mark , Morales Gracia , Rahawi Shahad , G. C. Kedar , Picazo Juan José , Im Weonbin , Shaw Karen Joy , Stein Jeffrey L.
Published: September 2010

Staphylococcal resistance to linezolid (LZD) is mediated through ribosomal mutations (23S rRNA or ribosomal proteins L3 and L4) or through methylation of 23S rRNA by the horizontally transferred Cfr methyltransferase. To investigate the structural basis for oxazolidinone activity against LZD-resistant (LZD
r
) strains, we compared structurally diverse, clinically relevant oxazolidinones, including LZD, radezolid (RX-1741), TR-700 (torezolid), and a set of TR-700 analogs (including novel CD-rings and various A-ring C-5 substituents), against a panel of laboratory-derived and clinical LZD
r
Staphylococcus aureus
strains possessing a variety of resistance mechanisms. Potency against all strains was correlated with optimization of C- and D-rings, which interact with more highly conserved regions of the peptidyl transferase center binding site. Activity against
cfr
strains was retained with either hydroxymethyl or 1,2,3-triazole C-5 groups but was reduced by 2- to 8-fold in compounds with acetamide substituents. LZD, which possesses a C-5 acetamide group and lacks a D-ring substituent, demonstrated the lowest potency against all strains tested, particularly against
cfr
strains. These data reveal key features contributing to oxazolidinone activity and highlight structural tradeoffs between potency against susceptible strains and potency against strains with various resistance mechanisms.
Elevated Linezolid Resistance in Clinical
cfr
-Positive
Staphylococcus aureus
Isolates Is Associated with Co-Occurring Mutations in Ribosomal Protein L3
Authors: Locke Jeffrey B. , Morales Gracia , Hilgers Mark , G. C. Kedar , Rahawi Shahad , José Picazo Juan , Shaw Karen Joy , Stein Jeffrey L.
Published: September 2010

Resistance to linezolid (LZD) occurs through mutations in 23S rRNA and ribosomal proteins L3 and L4 or through methylation of 23S rRNA by Cfr. Here we report novel L3 mutations, ΔSer145/His146Tyr and ΔMet169-Gly174, co-occurring with
cfr
in LZD-resistant
Staphylococcus aureus
isolates recovered from a hospital outbreak in Madrid, Spain. LZD MIC values (16, 32, or 64 μg/ml) correlated with the presence and severity of the L3 mutation. All isolates had TR-700 (torezolid) MIC values of ≤2 μg/ml.
Outer Membrane Protein X (Ail) Contributes to
Yersinia pestis
Virulence in Pneumonic Plague and Its Activity Is Dependent on the Lipopolysaccharide Core Length
Authors: Kolodziejek Anna M. , Schnider Darren R. , Rohde Harold N. , Wojtowicz Andrzej J. , Bohach Gregory A. , Minnich Scott A. , Hovde Carolyn J.
Published: September 2010

Yersinia pestis
, the causative agent of plague, is one of the most virulent microorganisms known. The outer membrane protein X (OmpX) in
Y. pestis
KIM is required for efficient bacterial adherence to and internalization by cultured HEp-2 cells and confers resistance to human serum. Here, we tested the contribution of OmpX to disease progression in the fully virulent
Y. pestis
CO92 strain by engineering a deletion mutant and comparing its ability in mediating pneumonic plague to that of the wild type in two animal models. The deletion of OmpX delayed the time to death up to 48 h in a mouse model and completely attenuated virulence in a rat model of disease. All rats challenged with 1 × 10
8
CFU of the
ompX
mutant survived, compared to the 50% lethal dose (LD
50
) of 1.2 × 10
3
CFU for the wild-type strain. Because murine serum is not bactericidal for the
ompX
mutant, the mechanism underlying the delay in time to death in mice was attributed to loss of adhesion/internalization properties but not serum resistance. The rat model, which is most similar to humans, highlighted the critical role of serum resistance in disease. To resolve conflicting evidence for the role of
Y. pestis
lipopolysaccharide (LPS) and OmpX in serum resistance,
ompX
was cloned into
Escherichia coli
D21 and three isogenic derivatives engineered to have progressively truncated LPS core saccharides. OmpX-mediated serum resistance, adhesiveness, and invasiveness, although dependent on LPS core length, displayed these functions in
E. coli
, independently of other
Yersinia
proteins and/or LPS. Also, autoaggregation was required for efficient OmpX-mediated adhesiveness and internalization but not serum resistance.
Effects of Chilling and Pruning in Forcing Dormant Black Cherry
Authors: Farmer Jr. R. E. , Barnett P. E. , Hall G. C.
Published: September 2010

In response to forcing after several chilling periods, seedlings from a low-elevation source in the southern Appalachian mountains broke dormancy earlier than high-elevation seedlings. Pruned stems responded more rapidly to forcing than intact stems, suggesting existence of an apex-to-base gradient in chilling requirement.
Effect of Exogenous Growth Substances on Cone Development in Scots pine (Pinussylvestris L.)
Authors: Brown Ian R. , Sauvé Elaine M.
Published: September 2010

A number of growth substances were applied to unpollinated strobili of Scots pine to test their effect on cone development. Unpollinated strobili are normally shed early in the growing season; the application of anti-auxins stimulated cone loss but indolebutyric acid and cytokinin reduced cone loss in comparison with unpollinated controls. The development of treated cones was associated with various morphological abnormalities. Mixtures of growth substances and pollen were found to be no more effective than pollen alone in terms of yield of seed.
Cell Dimensions and their Relationship to the Chemical Nature of the Lignin from the Wood of Broad-leaved Trees
Authors: Musha Y. , Goring D. A. I.
Published: September 2010

The dimensions of the various structural elements of 14 samples of wood from 10 broad-leaved species were determined by ultraviolet and scanning electron microscopy. A relationship was found between the chemical structure of the lignins and the morphological characteristics of the woods. The ratio of the thickness of the double cell wall of the fibres to their width increased with the increasing syringyl content of the lignin. A similar increase with syringyl content of the lignin was noted for the ratio of the vessel wall thickness to the vessel width. It is suggested that these trends are related to the availability of oxygen during the lignification process.
A Test of Cluster Sampling in Forest Inventories
Authors: Bonnor G. M.
Published: September 2010

During a recent pilot survey in Newfoundland, forest data were collected using a stratified, one-stage cluster-sampling design. The data were analyzed to determine if, within the stratified framework, cluster sampling would be more efficient than simple random sampling. Each cluster consisted of five point-samples located in a straight line. For the analysis, volume and variance estimates were determined from clusters of 1,2,3,4 and 5 points. During the survey, records were kept of the time required to complete various field-sampling tasks. These were used in lieu of cost data in the analysis. Results indicated that, for the given conditions, simple random sampling was more efficient than cluster sampling. However, relatively small changes in the conditions would make cluster sampling more efficient.
Promotion of Sucker Development on Populustremuloides Root Cuttings by an Antiauxin
Authors: Schier George A.
Published: September 2010

Aspen (Populustremuloides Michx.) root cuttings collected in June, when endogenous auxin levels are high, were treated with α-(p-chlorophenoxy)isobutyric acid (CPIBA), an apparent antiauxin, to determine the effect on subsequent sucker development. CPIBA relieved auxin inhibition in the excised roots and thus increased the number of suckers produced on each root.
The Early Mesozoic evolution of the Western Greater Caucasus (Russia): Triassic–Jurassic sedimentary and magmatic history
Authors: McCann T. , Chalot-Prat F. , Saintot A.
Published: September 2010

The Greater Caucasus (GC) forms a high Alpine fold-and-thrust belt on the southern margin of the East European Platform (EEP). The Triassic, and particularly, the Jurassic history of the Western Greater Caucasus region is important for our understanding of the palaeogeographic and tectonic evolution of the western Tethys area. In order to better constrain the nature and relevance of these events in the evolution of the region, which are classically described as the Late Triassic to Late Jurassic Cimmerian events, a field campaign in the Western Greater Caucasus was undertaken. Analysis of structural, sedimentological and petrological data from 41 sites in the Fore-Caucasus (Malaya Laba, Mount Tkhach-Belaya River), the Central Greater Caucasus (Georgievskoye, Otdaleni) and Southern Slope (Krasnaya Poliana) areas of the Western Greater Caucasus revealed that a broad asymmetric basin, with associated emergent volcanic islands, formed in the area in Jurassic times. Incipient back-arc rifting in Pliensbachian times was coeval with similar rifting episodes in the Pontides and South Caspian Sea areas. The synchroneity of these events may have been related to the renewal of the Tethys subduction to the south of the Eo-Cimmerian accretionary belt. Rift reactivation, with significant thinning of the continental lithosphere, occurred in the Aalenian. Despite the strong Alpine tectonic overprinting, some structural data confirms that the extension trend was east–west (almost parallel to the active margin) resulting in the formation of a series of pull-apart basins in the GC and the South Caspian region behind the Eastern Pontides–Lesser Caucasus subduction-related volcanic belt. In Bajocian times, subduction-related volcanic activity largely expanded from the Eastern Pontides–Lesser Caucasus to encompass the Transcaucasus, the southern part of GC and the Crimea region. Such widening of the volcanic arc was probably due to a shallowing of the northward subducting slab. In the back-arc GC region, this signalled the onset of the post-rift stage. The return of the slab to normal steepness resulted in subsidence in the back-arc region and in the GC with extensive accommodation space creation. This was subsequently filled by the Late Jurassic, Cretaceous and Cenozoic sedimentary successions.
Evolution of the Late Cenozoic basins of Georgia (SW Caucasus): a review
Authors: Adamia Sh. , Alania V. , Chabukiani A. , Chichua G. , Enukidze O. , Sadradze N.
Published: September 2010

The tectonic and geological evolution of Georgia and the Caucasus, on the whole, are largely determined by its position between the still converging Eurasian and Africa–Arabian lithosphere plates, within the wide zone of a continent–continent collision. The region in the Late Proterozoic–Early Cenozoic belonged to the now-vanished Tethys Ocean and its northern (Eurasian) and southern (Africa–Arabian) margins. Within this convergence zone there existed a system of island arcs, intra-arc rifts, back-arc basins characteristic of the pre-collisional stage. During syncollisional (the Oligocene–Middle Miocene) and post-collisional (the Late Miocene–Quaternary) stages, at the place of back-arc basins were formed fold and thrust belts of the Greater and Lesser Caucasus separated by the Transcaucasian intermontane lowland. Starting from the Late Miocene and as far as the end of the Pleistocene, in the central part of the region, simultaneously with formation of molassic basins and accumulation of coarse molasses there took place volcanic eruptions in subaerial conditions. According to the numerous data obtained during past decades we present a review on the lithological and structural characteristics of these collisional basins and on the coeval magmatic events.
Subductions, obduction and collision in the Lesser Caucasus (Armenia, Azerbaijan, Georgia), new insights
Authors: Sosson M. , Rolland Y. , Müller C. , Danelian T. , Melkonyan R. , Kekelia S. , Adamia S. , Babazadeh V. , Kangarli T. , Avagyan A. , Galoyan G. , Mosar J.
Published: September 2010

In the Lesser Caucasus three main domains are distinguished from SW to NE: (1) the autochthonous South Armenian Block (SAB), a Gondwana-derived terrane; (2) the ophiolitic Sevan–Akera suture zone; and (3) the Eurasian plate. Based on our field work, new stratigraphical, petrological, geochemical and geochronological data combined with previous data we present new insights on the subduction, obduction and collision processes recorded in the Lesser Caucasus. Two subductions are clearly identified, one related to the Neotethys subduction beneath the Eurasian margin and one intra-oceanic (SSZ) responsible for the opening of a back-arc basin which corresponds to the ophiolites of the Lesser Caucasus. The obduction occurred during the Late Coniacian to Santonian and is responsible for the widespread ophiolitic nappe outcrop in front of the suture zone. Following the subduction of oceanic lithosphere remnants under Eurasia, the collision of the SAB with Eurasia started during the Paleocene, producing 1) folding of ophiolites, arc and Upper Cretaceous formations (Transcaucasus massif to Karabakh); 2) thrusting toward SW; and 3) a foreland basin in front of the belt. Upper–Middle Eocene series unconformably cover the three domains. From Eocene to Miocene as a result of the Arabian plate collision with the SAB to the South, southward propagation of shortening featured by folding and thrusting occurred all along the belt. These deformations are sealed by a thick sequence of unconformable Miocene to Quaternary clastic and volcanic rocks of debated origin.
New and revised radiolarian biochronology for the sedimentary cover of ophiolites in the Lesser Caucasus (Armenia)
Authors: Danelian T. , Asatryan G. , Sahakyan L. , Galoyan GH. , Sosson M. , Avagyan A.
Published: September 2010

In order to improve our understanding of the palaeogeographic and geodynamic evolution of the Tethyan realms preserved in the Lesser Caucasus we here review the existing data for the sedimentary cover of ophiolites preserved in Armenia. Particular attention is given to those dated sedimentary rocks that are in direct genetic contact with ophiolitic lavas, as they provide constraints for submarine oceanic activity. The oldest available ages come from the Sevan–Akera suture zone that point to a Late Triassic oceanization. Data from both the Sevan and Vedi ophiolites provide evidence for Middle Jurassic (Bajocian) submarine activity, that continued until at least the Late Jurassic (Mid/Late Oxfordian to Late Kimmeridgian/Early Tithonian), as dated recently in Stepanavan and in this study for the Vedi ophiolite.
Structure of the Earth's crust and upper mantle of the West- and East-Black Sea Basins revealed from geophysical data and its tectonic implications
Authors: Yegorova Tamara , Gobarenko Valentina
Published: September 2010

A back-arc Black Sea Basin consists of two deep sub-basins – the West-Black Sea (WBS) and the East-Black Sea (EBS) – filled with thick sediments (up to 12–14 km), which are separated by the mid–Black Sea Ridge (MBSR) – a NW trending basement uplift structure. For a better understanding of the lithosphere structure of these two sub-basins, the authors made a comprehensive analysis of the available geological and geophysical data, including carrying out a three-dimensional (3D) gravity back-stripping analysis, a reinterpretation of a number of seismic refraction profiles as well as the re-evaluation of seismological data and local seismic tomography. Inferred differences in the basin architecture and lithosphere structure of the WBS and EBS can be explained by different affinities of the underlying crustal domains and by the peculiarities of their (Cretaceous and younger) rift and post-rift history. Rifting that led to oceanic crust formation in the WBS occurred within the continental crust of the Moesian Platform along Mesozoic sutures with adjoining accreted terranes. The EBS, most probably, formed within the Transcaucasus continental domain due to strike–slip movements along the MBSR. Underthrusting of the EBS oceanic lithosphere beneath the continental domain of the Scythian Platform led to the formation offshore of the Crimean orogen of accretional wedge of Sorokin Trough.
Methane in the northern Black Sea: characterization of its geomorphological and geological environments
Authors: Starostenko V. I. , Rusakov O. M. , Shnyukov E. F. , Kobolev V. P. , Kutas R. I.
Published: September 2010

Based on hydro-acoustic and geophysical observations, this paper presents an analysis of geomorphological and geological settings of gas methane occurrence on the NW shelf and upper continental slope, in the Sorokin trough and on the Kerch-Taman offshore, in the Black Sea. Gases are associated with seeps, mud volcanoes and gas hydrates. Evidence is given for the thermogenic nature of methane. The gas methane is of mostly abiogenic origin. Small gas releases may be produced by the decomposition of Quaternary organic material near the sea floor through the action of bacteria or biodegradation of redeposited thermogenic hydrocarbons. The origin of carbonate formations is related to degassing sedimentary layers. There is a possible role for deep faults in transporting gas to the sea floor. The gas hydrate stability zone in the Black Sea lies at minimum water depth of 600–650 m with its thickness up to 500 m.
Cretaceous–Neogene tectonic evolution of the northern margin of the Black Sea from seismic reflection data and tectonic subsidence analysis
Authors: Khriachtchevskaia O. , Stovba S. , Stephenson R.
Published: September 2010

Three fundamental stages of the Cretaceous–Neogene tectonic evolution of the Odessa Shelf and Azov Sea (northern margins of western and eastern Black Sea basins, respectively) have been documented from the analysis of reinterpreted regional seismic profiling and one-dimensional (1-D) subsidence analysis of 49 wells, for which the stratigraphic interpretation was recently revised. (1) An initial active rifting stage began within the Early Cretaceous (not later than Aptian–Albian times) and continued until the end of the Santonian in the Late Cretaceous (
c
. 128–83 Ma). A system of half-grabens with mainly south-dipping normal faults developed on the Odessa Shelf at this time. The most profound faulting, accompanied by volcanic activity, occurred in the NE–SW orientated Karkinit-Gubkin rift basin at the boundary between the Eastern European and Scythian platforms. The footwalls of half-grabens were exposed above sea level and subject to erosion at this time. Active extensional processes affected the western part of Azov Sea and, while the onset and cessation of these cannot be tightly constrained, they are compatible with the well constrained results from the Odessa Shelf. (2) The second tectonic stage is one of passive post-rift thermal subsidence that lasted from the Campanian (Late Cretaceous) until the end of the Middle Eocene (83–38.6 Ma). (3) The third stage of basin evolution is one of inversion tectonics in a compressional setting. Discrete inversion events occurred at the end of the Middle Eocene, during the Late Eocene, during the Early Miocene and at Middle Miocene times (
c
. 38.6 Ma,
c
. 35.4 Ma,
c
. 16.3 Ma,
c
. 10.4 Ma, respectively) and typical inversion structures developed on the Odessa Shelf, some parts of which were uplifted and significantly eroded (down to the Lower Cretaceous succession). The southern part of the Azov Sea, opening into the northernmost eastern Black Sea basin, subsided rapidly during this time; thereafter, until the Quaternary, rapid subsidence was limited to its southeastern part, which was incorporated into the Indolo-Kuban foreland basin of the Greater Caucasus orogen.
Leveraging redundancy in sampling-interpolation applications for sensor networks
Authors: Liaskovitis Periklis G. , Schurgers Curt
Published: September 2010

An important class of sensor network applications aims at estimating the spatiotemporal behavior of a physical phenomenon, such as temperature variations over an area of interest. In such a scenario, the network essentially acts as a distributed sampling system. However, unlike in the event detection case, the notion of sensing range is largely meaningless for sampling-interpolation applications. As a result, existing techniques to exploit sensing redundancy in event detection settings, which rely on the existence of such sensing range, become unusable. Instead, this article presents a new method to exploit redundancy for the sampling class of applications by selecting a suitable set of sensors to act as sampling points. Through online estimation of process characteristics, sufficiently accurate interpolation can be achieved. We illustrate an algorithm to obtain multiple disjoint sets and demonstrate significant reductions in the number of active sensors for a wide range of synthetic sensor data.
Coverage properties of clustered wireless sensor networks
Authors: Machado Renita , Zhang Wensheng , Wang Guiling , Tekinay Sirin
Published: September 2010

This article studies clustered wireless sensor networks (WSNs), a realistic topology resulting from common deployment methods. We study coverage in
naturally clustered
networks of wireless sensor nodes, as opposed to WSNs where clustering is facilitated by selection. We show that along with increasing the vacancy in random placement of nodes in a WSN, it also alters the connectivity properties in the network. We analyze varying levels of redundancy to determine the probability of coverage in the network. The phenomenon of clustering in networks of wireless sensor nodes raises interesting questions for future research and development. The article provides a foundation for the design to optimize network performance with the constraint of sensing coverage.
Analyzing MAC protocols for low data-rate applications
Authors: Langendoen Koen , Meier Andreas
Published: September 2010

The fundamental WSN requirement to be energy-efficient has produced a whole range of specialized Medium Access Control (MAC) protocols. They differ in how performance (latency, throughput) is traded off for a reduction in energy consumption. The question “which protocol is best?” is difficult to answer because (i) this depends on specific details of the application requirements and hardware characteristics involved, and (ii) protocols have mainly been assessed individually with each outperforming the canonical S-MAC protocol, but with different simulators, hardware platforms, and workloads. This article addresses that void for low data-rate applications where collisions are of little concern, making an analytical approach tractable in which latency and energy consumption are modeled as a function of key protocol parameters (duty cycle, slot length, number of slots, etc.). By exhaustive search we determine the Pareto-optimal protocol settings for a given workload (data rate, network topology). Of the protocols compared we find that WiseMAC strikes the best latency vs. energy-consumption trade-off across the range of workloads considered. In particular, its random access scheme in combination with local synchronization does not only minimize protocol overhead, but also maximizes the available channel bandwidth.
The byzantine empire in the intercloud
Authors: Vukolić Marko
Published: September 2010

The relevance of Byzantine fault tolerance in the context of cloud computing has been questioned [3]. While arguments against Byzantine fault tolerance seemingly makes sense in the context of a single cloud, i.e., a large-scale cloud infrastructure that resides under control of a single, typically commercial provider, these arguments are less obvious in a broader context of the Intercloud, i.e., a cloud of multiple, independent clouds.

In this paper, we start from commonly acknowledged issues that impede the adoption of Byzantine fault tolerance within a single cloud, and argue that many of these issues fade when Byzantine fault tolerance in the Intercloud is considered.
Temporal microRNA expression during in vitro myogenic progenitor cell proliferation and differentiation: regulation of proliferation by miR-682
Authors: Chen Yongxin , Gelfond Jonathan , McManus Linda M. , Shireman Paula K.
Published: September 2010

MicroRNAs (miRNAs) regulate gene expression by repressing target genes at the posttranscriptional level. Since miRNAs have unique expression profiles in different tissues, they provide pivotal regulation of many biological processes. The present study defined miRNA expression during murine myogenic progenitor cell (MPC) proliferation and differentiation to identify miRNAs involved in muscle regeneration. Muscle-related gene expression analyses revealed that the time course and expression of myosin heavy chain (MHC) and transcription factors (Myf5, MyoD, myogenin, and Pax7) were similar during in vitro MPC proliferation/differentiation and in vivo muscle regeneration. Comprehensive profiling revealed that 139 or 16 miRNAs were significantly changed more than twofold [false discovery rate (FDR) < 0.05] during MPC differentiation or proliferation, respectively; cluster analyses revealed five distinct patterns of miRNA expression during the time course of MPC differentiation. Not unexpectedly, the largest miRNA changes occurred in muscle-specific miRNAs (miR-1, -133a, and -499), which were upregulated >10-fold during MPC differentiation (FDR < 0.01). However, several previously unreported miRNAs were differentially expressed, including miR-10b, -335-3p, and -682. Interestingly, the temporal patterns of miR-1, -499, and -682 expression during in vitro MPC proliferation/differentiation were remarkably similar to those observed during in vivo muscle regeneration. Moreover, in vitro inhibition of miR-682, the only miRNA upregulated in proliferating compared with quiescent MPC, led to decreased MPC proliferation, further validating our in vitro assay system for the identification of miRNAs involved in muscle regeneration. Thus the differentially expressed miRNAs identified in the present study could represent new regulatory elements in MPC proliferation and differentiation.
Assessing Physical Performance in Centenarians: Norms and an Extended Scale from the Georgia Centenarian Study
Authors: Cress M. Elaine , Gondo Yasuyuki , Davey Adam , Anderson Shayne , Kim Seock-Ho , Poon Leonard W.
Published: September 2010

Centenarians display a broad variation in physical abilities, from independence to bed-bound immobility. This range of abilities makes it difficult to evaluate functioning using a single instrument. Using data from a population-based sample of 244 centenarians (MAge= 100.57 years, 84.8% women, 62.7% institutionalized, and 21.3% African American) and 80 octogenarians (MAge= 84.32 years, 66.3% women, 16.3% institutionalized, and 17.5% African American) we (1) provide norms on the Short Physical Performance Battery and (2) extend the range of this scale using performance on additional tasks and item response theory (IRT) models, reporting information on concurrent and predictive validity of this approach. Using the original SPPB scoring criteria, 73.0% of centenarian men and 86.0% of centenarian women are identified as severely impaired by the scale's original classification scheme. Results suggest that conventional norms for older adults need substantial revision for centenarian populations and that item response theory methods can be helpful to address floor and ceiling effects found with any single measure.
Development of a FLIPR Assay for the Simultaneous Identification of MrgD Agonists and Antagonists from a Single Screen
Authors: Ajit Seena K. , Pausch Mark H. , Kennedy Jeffrey D. , Kaftan Edward J.
Published: September 2010

MrgD, a member of the Mas-related gene family, is expressed exclusively in small diameter neurons in the dorsal root ganglion. This unique expression pattern, the presence of a single copy of MrgD in rodents and humans, and the identification of a putative ligand, beta-alanine, make it an experimentally attractive therapeutic target for pain with limited likelihood of side effects. We have devised a high throughput calcium mobilization assay that enables identification of both agonists and antagonists from a single screen for MrgD. Screening of the Library of Pharmacologically Active Compounds (LOPAC) validated this assay approach, and we identified both agonists and antagonists active at micromolar concentrations in MrgD expressing but not in parental CHO-DUKX cell line. Further characterization was performed using a subset of these screening hits. Our results demonstrated that the dual agonist/antagonist assay format is feasible and likely can be extended to most GPCRs with known agonist.
Role of Glutathione in the Regulation of Cisplatin Resistance in Cancer Chemotherapy
Authors: Chen Helen H. W. , Kuo Macus Tien
Published: September 2010

Three mechanisms have been proposed for the role of glutathione (GSH) in regulating cisplatin (CDDP) sensitivities that affects its ultimate cell-killing ability: (i) GSH may serve as a cofactor in facilitating multidrug resistance protein 2- (MRP2-) mediated CDDP efflux in mammalian cells, sinceMRP2-transfected cells were shown to confer CDDP resistance; (ii) GSH may serve as a redox-regulating cytoprotector based on the observations that many CDDP-resistant cells overexpress GSH andγ-glutamylcysteine synthesis (γ-GCS), the rate-limiting enzyme for GSH biosynthesis; (iii) GSH may function as a copper (Cu) chelator. Elevated GSH expression depletes the cellular bioavailable Cu pool, resulting in upregulation of the high-affinity Cu transporter (hCtr1) which is also a CDDP transporter. This has been demonstrated that overexpression of GSH by transfection withγ-GCS conferred sensitization to CDDP toxicity. This review describes how these three models were developed and critically reviews their importance to overall CDDP cytotoxicity in cancer cell treatments.
Combinatorial Aspects of the Generalized Euler′s Totient
Authors: Pabhapote Nittiya , Laohakosol Vichian
Published: September 2010

A generalized Euler′s totient is defined as a Dirichlet convolution of a power function and a product of the Souriau‐Hsu‐Möbius function with a completely multiplicative function. Two combinatorial aspects of the generalized Euler′s totient, namely, its connections to other totients and its relations with counting formulae, are investigated.
Monitoring of Lead in Topsoil, Forage, Blood, Liver, and Kidneys in Cows in a Lead-Polluted Area in Slovenia (1975–2002) and a Case of Lead Poisoning (1993)
Authors: Zadnik T.
Published: September 2010

The paper presents the results of a prolonged research in a lead-polluted area. Extensive systematic studies of lead concentrations in topsoil, forage, blood, liver, and kidney in cows on farms within 1–10 km around the lead mine and smelter were carried out. After installation of a filter in 1978, lead concentrations began to decrease. However, when toxic levels of lead were within normal reference values, the authorities stopped to finance the project. In 2002, the research was concluded. A review of studies showed that the protective filter was effective; during the period 1975–2002 mean lead in forage dropped from 584.0 ± 324.0 to 5.5 ± 2.9 mg/kg, and the mean blood lead levels dropped from 1.251 ± 0.580 to 0.069 ± 0.041 mg/kg. Three years after the filter was installed the amount of lead in the liver and kidneys had normalized. Closely related to our research was also a case of cow lead poisoning.
HIV-Associated Tuberculosis
Authors: Naidoo Kogieleum , Naidoo Kasavan , Padayatchi Nesri , Abdool Karim Quarraisha
Published: September 2010

The intersecting HIV and Tuberculosis epidemics in countries with a high disease burden of both infections pose many challenges and opportunities. For patients infected with HIV in high TB burden countries, the diagnosis of TB, ARV drug choices in treating HIV-TB coinfected patients, when to initiate ARV treatment in relation to TB treatment, managing immune reconstitution, minimising risk of getting infected with TB and/or managing recurrent TB, minimizing airborne transmission, and infection control are key issues. In addition, given the disproportionate burden of HIV in women in these settings, sexual reproductive health issues and particular high mortality rates associated with TB during pregnancy are important. The scaleup and resource allocation to access antiretroviral treatment in these high HIV and TB settings provide a unique opportunity to strengthen both services and impact positively in meeting Millennium Development Goal 6.
A Comparison of PAM50 Intrinsic Subtyping with Immunohistochemistry and Clinical Prognostic Factors in Tamoxifen-Treated Estrogen Receptor–Positive Breast Cancer
Authors: Nielsen Torsten O. , Parker Joel S. , Leung Samuel , Voduc David , Ebbert Mark , Vickery Tammi , Davies Sherri R. , Snider Jacqueline , Stijleman Inge J. , Reed Jerry , Cheang Maggie C.U. , Mardis Elaine R. , Perou Charles M. , Bernard Philip S. , Ellis Matthew J.
Published: September 2010

Purpose: To compare clinical, immunohistochemical (IHC), and gene expression models of prognosis applicable to formalin-fixed, paraffin-embedded blocks in a large series of estrogen receptor (ER)–positive breast cancers from patients uniformly treated with adjuvant tamoxifen.

Experimental Design: Quantitative real-time reverse transcription-PCR (qRT-PCR) assays for 50 genes identifying intrinsic breast cancer subtypes were completed on 786 specimens linked to clinical (median follow-up, 11.7 years) and IHC [ER, progesterone receptor (PR), HER2, and Ki67] data. Performance of predefined intrinsic subtype and risk-of-relapse scores was assessed using multivariable Cox models and Kaplan-Meier analysis. Harrell's C-index was used to compare fixed models trained in independent data sets, including proliferation signatures.

Results: Despite clinical ER positivity, 10% of cases were assigned to nonluminal subtypes. qRT-PCR signatures for proliferation genes gave more prognostic information than clinical assays for hormone receptors or Ki67. In Cox models incorporating standard prognostic variables, hazard ratios for breast cancer disease-specific survival over the first 5 years of follow-up, relative to the most common luminal A subtype, are 1.99 [95% confidence interval (CI), 1.09-3.64] for luminal B, 3.65 (95% CI, 1.64-8.16) for HER2-enriched subtype, and 17.71 (95% CI, 1.71-183.33) for the basal-like subtype. For node-negative disease, PAM50 qRT-PCR–based risk assignment weighted for tumor size and proliferation identifies a group with >95% 10-year survival without chemotherapy. In node-positive disease, PAM50-based prognostic models were also superior.

Conclusion: The PAM50 gene expression test for intrinsic biological subtype can be applied to large series of formalin-fixed, paraffin-embedded breast cancers, and gives more prognostic information than clinical factors and IHC using standard cut points. Clin Cancer Res; 16(21); 5222–32. ©2010 AACR.
Regulation of Cell Cycle Genes and Induction of Senescence by Overexpression of OTX2 in Medulloblastoma Cell Lines
Authors: Bunt Jens , de Haas Talitha G. , Hasselt Nancy E. , Zwijnenburg Danny A. , Koster Jan , Versteeg Rogier , Kool Marcel
Published: September 2010

The transcription factor orthodenticle homeobox 2 (OTX2) has been implicated in the pathogenesis of medulloblastoma, as it is often highly expressed and sometimes amplified in these tumors. Little is known of the downstream pathways regulated by OTX2. We therefore generated MED8A and DAOY medulloblastoma cell lines with doxycycline-inducible OTX2 expression. In both cell lines, OTX2 inhibited proliferation and induced a senescence-like phenotype with senescence-associated β-galactosidase activity. Expression profiles of time series after OTX2 induction in MED8A showed early upregulation of cell cycle genes related to the G2-M phase, such as AURKA, CDC25C, and CCNG2. Paradoxically, G1-S phase genes such as MYC, CDK4, CDK6, CCND1, and CCND2 were strongly downregulated, in line with the observed G1 arrest. ChIP-on-chip analyses of OTX2 binding to promoter regions in MED8A and DAOY showed a strong enrichment for binding to the G2-M genes, suggesting a direct activation. Their mRNA expression correlated with OTX2 expression in primary tumors, underscoring the in vivo relevance of this regulation. OTX2 induction activated the P53 pathway in MED8A, but not in DAOY, which carries a mutated P53 gene. In DAOY cells, senescence-associated secretory factors, such as interleukin-6 and insulin-like growth factor binding protein 7, were strongly upregulated after OTX2 induction. We hypothesize that the imbalance in cell cycle stimulation by OTX2 leads to cellular senescence either by activating the P53 pathway or through the induction of secretory factors. Our data indicate that OTX2 directly induces a series of cell cycle genes but requires cooperating genes for an oncogenic acceleration of the cell cycle. Mol Cancer Res; 8(10); 1344–57. ©2010 AACR.
Long-Term Benefit of Primary Prevention With an Implantable Cardioverter-Defibrillator
Authors: Goldenberg Ilan , Gillespie John , Moss Arthur J. , Hall W. Jackson , Klein Helmut , McNitt Scott , Brown Mary W. , Cygankiewicz Iwona , Zareba Wojciech ,   and the Executive Committee of the Multicenter Automatic Defibrillator Implantation Trial II
Published: September 2010

Background—

The Multicenter Automatic Defibrillator Implantation Trial II (MADIT-II) showed a significant 31 reduction in the risk of death with primary implantable cardioverter-defibrillator (ICD) therapy during a median follow-up of 1.5 years. However, currently there are no data on the long-term efficacy of primary defibrillator therapy.

Methods and Results—

MADIT-II enrolled 1232 patients with ischemic left ventricular dysfunction who were randomized to ICD and non-ICD medical therapy and were followed up through November 2001. For the present long-term study, we acquired posttrial mortality data through March 2009 for all study participants (median follow-up, 7.6 years). Multivariate Cox proportional hazards regression modeling was performed to calculate the hazard ratio for ICD versus non-ICD therapy during long-term follow-up. At 8 years of follow-up, the cumulative probability of all-cause mortality was 49 among patients treated with an ICD compared with 62 among non-ICD patients (
P
<0.001). Multivariate analysis demonstrated that ICD therapy was associated with a significant long-term survival benefit (hazard ratio for 0- through 8-year mortality=0.66 [95 confidence interval, 0.56 to 0.78];
P
<0.001). Treatment with an ICD was shown to be associated with a significant reduction in the risk of death during the early phase of the extended follow-up period (0 through 4 years: hazard ratio=0.61 [95 confidence interval, 0.50 to 0.76];
P
<0.001) and with continued life-saving benefit during the late phase of follow-up (5 through 8 years: hazard ratio=0.74 [95 confidence interval, 0.57 to 0.96];
P
=0.02).

Conclusions—

Our findings demonstrate a sustained 8-year survival benefit with primary ICD therapy in the MADIT-II population.
Observations, Simulations, and Dynamics of Jet Stream Variability and Annular Modes
Authors: Kidston Joseph , Frierson D. M. W. , Renwick J. A. , Vallis G. K.
Published: September 2010

The characteristics of the dominant pattern of extratropical variability (the so-called annular modes) are examined in the context of the theory that eddy-driven jets are self-maintaining. It is shown that there is genuine hemispheric symmetry in the variation of the zonal wind in the Southern Hemisphere but not the Northern Hemisphere. The annular mode is shown to be baroclinic in nature; it is associated with changes in the baroclinic eddy source latitude, and the latitude of the eddy source region is organized by the mean flow. This behavior is expected if there is a baroclinic feedback that encourages the maximum baroclinic instability to be coincident with the maximum zonal wind speed, and discourages the meridional vacillation of the eddy-driven jet stream. It is shown that the strength of the thermally indirect circulation that gives rise to the baroclinic feedback appears to influence the time scale of the annular mode. When the thermally indirect circulation is stronger the annular mode has a longer e-folding time in a simplified GCM. Preliminary results indicate that the same dynamics are important in the real atmosphere.