bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scalar Turbulence in Convective Boundary Layers by Changing the Entrainment Flux
Authors: Lanotte Alessandra S. , Mazzitelli Irene M. 
Published: July 2012

Abstract
A large-eddy simulation model is adopted to investigate the evolution of scalars transported by atmospheric cloud-free convective boundary layer flows. Temperature fluctuations due to the ground release of sensible heat and concentration fluctuations of a trace gas emitted at the homogeneous surface are mixed by turbulence within the unstable boundary layer. On the top, the entrainment zone is varied to obtain two distinct situations: (i) the temperature inversion is strong and the trace gas increment across the entrainment region is small, yielding to a small top flux with respect to the surface emission; (ii) the temperature inversion at the top of the convective boundary layer is weak, and the scalar increment large enough to achieve a concentration flux toward the free atmosphere that overwhelms the surface flux. In both cases, an estimation of the entrainment flux is obtained within a simple model, and it is tested against numerical data. The evolution of the scalar profiles is discussed in terms of the different entrainment–surface flux ratios.
Results show that, when entrainment at the top of the boundary layer is weak, temperature and trace gas scalar fields are strongly correlated, particularly in the lower part of the boundary layer. This means that they exhibit similar behavior from the largest down to the smallest spatial scales. However, when entrainment is strong, as moving from the surface, differences in the transport of the two scalars arise.
Finally, it is shown that, independently of the scalar regime, the temperature field exhibits more intermittent fluctuations than the trace gas.
A Southwest Pacific Tropical Cyclone Climatology and Linkages to the El Niño–Southern Oscillation
Authors: Diamond Howard J. , Lorrey Andrew M. , Renwick James A. 
Published: July 2012

Abstract
The new South Pacific Enhanced Archive for Tropical Cyclones (SPEArTC) dataset provides an opportunity to develop a more complete climatology of tropical cyclones (TCs) in the southwest Pacific. Here, spatial patterns and characteristics of TCs for the 41-yr period beginning with the 1969/70 season are related to phases of the El Niño–Southern Oscillation (ENSO), taking into account the degree of ocean–atmosphere coupling. Twentieth-century reanalysis data and the coupled ENSO index (CEI) were used to investigate TC genesis areas and climate diagnostics in the extratropical transition (ETT) region at and south of 25°S during different CEI ENSO phases. This is the first study looking at CEI-based ENSO phases and the more detailed relationship of TCs to the coupling of the ocean and atmosphere during different ENSO phases. Consistent with previous findings, positive relationships exist among TCs, sea surface temperature, and atmospheric circulation. A statistically significant greater frequency of major TCs was found during the latter half of the study period (1991–2010) compared to the 1970–90 period, again consistent with the findings of other studies. Also found were significant and consistent linkages highlighting the interplay of TCs and sea surface temperature (SSTs) in the southwest Pacific basin west of 170°E and a closer connection to atmospheric circulation east of 170°E. Moreover, this study demonstrates subtle differences between a fully coupled El Niño or La Niña and atmospheric- or ocean-dominated phases, or neutral conditions.
Comparative analysis of diguanylate cyclase and phosphodiesterase genes in Klebsiella pneumoniae
Authors: Cruz Diana P , Huertas Mónica G , Lozano Marcela , Zárate Lina , Zambrano María Mercedes 
Published: July 2012

Abstract

Background

Klebsiella pneumoniae can be found in environmental habitats as well as in hospital settings where it is commonly associated with nosocomial infections. One of the factors that contribute to virulence is its capacity to form biofilms on diverse biotic and abiotic surfaces. The second messenger Bis-(3’-5’)-cyclic dimeric GMP (c-di-GMP) is a ubiquitous signal in bacteria that controls biofilm formation as well as several other cellular processes. The cellular levels of this messenger are controlled by c-di-GMP synthesis and degradation catalyzed by diguanylate cyclase (DGC) and phophodiesterase (PDE) enzymes, respectively. Many bacteria contain multiple copies of these proteins with diverse organizational structure that highlight the complex regulatory mechanisms of this signaling network. This work was undertaken to identify DGCs and PDEs and analyze the domain structure of these proteins in K. pneumoniae.

Results
A search for conserved GGDEF and EAL domains in three sequenced K. pneumoniae genomes showed that there were multiple copies of GGDEF and EAL containing proteins. Both single domain and hybrid GGDEF proteins were identified: 21 in K. pneumoniae Kp342, 18 in K. pneumoniae MGH 78578 and 17 in K. pneumoniae NTUH-K2044. The majority had only the GGDEF domain, most with the GGEEF motif, and hybrid proteins containing both GGDEF and EAL domains were also found. The I site for allosteric control was identified only in single GGDEF domain proteins and not in hybrid proteins. EAL-only proteins, containing either intact or degenerate domains, were also identified: 15 in Kp342, 15 in MGH 78578 and 10 in NTUH-K2044. Several input sensory domains and transmembrane segments were identified, which together indicate complex regulatory circuits that in many cases can be membrane associated.

Conclusions
The comparative analysis of proteins containing GGDEF/EAL domains in K. pneumoniae showed that most copies were shared among the three strains and that some were unique to a particular strain. The multiplicity of these proteins and the diversity of structural characteristics suggest that the c-di-GMP network in this enteric bacterium is highly complex and reflects the importance of having diverse mechanisms to control cellular processes in environments as diverse as soils or plants and clinical settings.
Estimating the re-identification risk of clinical data sets
Authors: Dankar Fida Kamal , El Emam Khaled , Neisa Angelica , Roffey Tyson 
Published: July 2012

AbstractBackgroundDe-identification is a common way to protect patient privacy when disclosing clinical data for secondary purposes, such as research. One type of attack that de-identification protects against is linking the disclosed patient data with public and semi-public registries. Uniqueness is a commonly used measure of re-identification risk under this attack. If uniqueness can be measured accurately then the risk from this kind of attack can be managed. In practice, it is often not possible to measure uniqueness directly, therefore it must be estimated.MethodsWe evaluated the accuracy of uniqueness estimators on clinically relevant data sets. Four candidate estimators were identified because they were evaluated in the past and found to have good accuracy or because they were new and not evaluated comparatively before: the Zayatz estimator, slide negative binomial estimator, Pitman’s estimator, and mu-argus. A Monte Carlo simulation was performed to evaluate the uniqueness estimators on six clinically relevant data sets. We varied the sampling fraction and the uniqueness in the population (the value being estimated). The median relative error and inter-quartile range of the uniqueness estimates was measured across 1000 runs.ResultsThere was no single estimator that performed well across all of the conditions. We developed a decision rule which selected between the Pitman, slide negative binomial and Zayatz estimators depending on the sampling fraction and the difference between estimates. This decision rule had the best consistent median relative error across multiple conditions and data sets.ConclusionThis study identified an accurate decision rule that can be used by health privacy researchers and disclosure control professionals to estimate uniqueness in clinical data sets. The decision rule provides a reliable way to measure re-identification risk.
Land-use and land-cover assessment for the study of lifestyle change in a rural Mexican community: The Maycoba Project
Authors: Giraldo Mario A , Chaudhari Lisa S , Schulz Leslie O 
Published: July 2012

Abstract

Background
In 1995, a study was conducted to identify the effects of traditional and westernized environments on the prevalence of type 2 diabetes in Pima Indians (Pimas) in Mexico and the United States. The study concluded that the more traditional lifestyle in Mexico had a protective effect against this metabolic disorder. In the ensuing 15 years, the environmental circumstances of the Mexican Pimas changed, and a follow-up study was conducted to determine the role environmental change plays in the development of diabetes in this genetically susceptible population. A major element of environmental transition relates to land-use and land-cover (LULC) changes that could affect physical activity and promote an obesogenic environment. This study examined changes in the region’s LULC to determine whether there have been transitions in agricultural land use and urbanization that would be consistent with a more sedentary lifestyle. Changes were assessed from 1994 aerial photographs and 2007 satellite images.

Results
The land-cover analysis showed that mixed vegetation and dense trees cover most of the study area. It suggested a rural environment that includes a low percentage of impermeable areas, and it indicated that the area experiencing human intervention covers 7% of the total area. The land-use-change findings showed a decrease or no change in agricultural or ranching areas and a decrease in farmland due to reforestation or revegetation. Three variables from the land-use-change analysis were examined as proxies for lifestyle change: urban development, dwelling-unit density, and variation in the road network. Two of the measures –the amount of urbanization and the number and density of dwelling units—showed increases, most notably in the town of Maycoba. There were only minor changes in the road network: most of the road segments are short and concentrated in Maycoba where most of the buildings, points of interest (e.g., church, stores), and cars are located.

Conclusions
The LULC in Maycoba and surrounding settlements had changed during the study period. LULC change was used as a proxy to examine lifestyle changes that can affect levels of physical activity.
Intravenous immunoglobulin treatment of the post-polio syndrome: sustained effects on quality of life variables and cytokine expression after one year follow up
Authors: Gonzalez Henrik , Khademi Mohsen , Borg Kristian , Olsson Tomas 
Published: July 2012

Abstract

Background
Expression of inflammatory cytokines in cerebrospinal fluid (CSF) has led to the hypothesis of intrathecal chronic inflammation to explain the denervation observed in post-polio syndrome (PPS). It has been shown that therapy with intravenous immunoglobulin (IVIG) improves physical performance and dampens down the inflammatory process at 6 months in PPS patients. We here examined the effects of IVIG on cytokine expression and clinical outcome one year after IVIG treatment.

Methods
From a previous study with 135 PPS patients included, 41 patients were further evaluated before un-blinding for one year (21 placebo and 20 treated with IVIG, Xepol® 50 mg/ml), and were assessed for clinical variables by performing the Short Form-36 survey (SF-36) questionnaire assessment, the 6 minute walk distance test (6MWT) and registering pain level by Visual Analogue Scale (VAS) after IVIG treatment. A separate cohort of 37 PPS patients went through lumbar puncture (LP) at baseline and 20 patients, treated with IVIG, repeated the LP one year later. Thirty patients affected with other neurological diseases (OND) were used as control group. Inflammatory cytokines TNF, TGFβ, IFNγ, IL-23, IL-13 and IL-10 were measured in blood cells and CSF cells with RT-PCR.

Results
Scores of the physical components of SF-36 were significantly higher at the one year follow up time-point in the IVIG-treated patients when compared to baseline as well as to the control subjects. Pain VAS score and 6MWT improved significantly in the IVIG-treated patients when compared with baseline Relative expression of TNF and IFN-γ in both PBMCs and CSF from PPS patients were increased compared to OND subjects at baseline (p < 0.05). One year after IVIG-treatment a decreased expression of IFN-γ and IL23 was found in CSF of PPS patients, while anti-inflammatory IL-13 was increased (p < 0.05).

Conclusions
IVIG has effects on relevant QoL variables and inflammatory cytokines up to one year in patients with PPS. This gives a basis for scheduling IVIG in upcoming trials with this therapy.
Airborne electromagnetic bathymetry and estimation of bedrock topography in Broken Bay, Australia
Authors: Vrbancich Julian 
Published: July 2012

A helicopter transient electromagnetic (TEM) survey was flown over shallow coastal waters in Broken Bay, Australia, overlying several palaeovalleys and exposed reef sections. The infilled palaeovalleys contain unconsolidated sediments with variable thicknesses exceeding 100 m. Previous marine seismic reflection and vibrocore studies provide an estimate of sediment thickness and surficial sediment conductivity, respectively, which, combined with known bathymetry (sonar soundings) and measured seawater conductivity, can be used to generate a crude 1D geoelectric ground-truth model consisting of two layers (seawater/sediment) overlying a relatively resistive basement. The primary focus was to examine the accuracy of interpreted water depths obtained by 1D inversion of airborne TEM data, assuming a two-layer over resistive basement model, by comparing these depths with known water depths. The secondary focus was to compare the interpreted sediment thickness (i.e., the thickness of the second geoelectric layer, which combined with bathymetry, gives the bedrock depth) with thicknesses estimated from marine seismic data to test the potential of using airborne electromagnetic systems for remote sensing of the coarse features of the bedrock topography. Interpreted water depths obtained from TEM data resulted in absolute water depth accuracies of 1–2 m for depths between 10 and 30 m, and 0.3–0.5 m in water shallower than [Formula: see text]. More importantly, similar water depth accuracies were obtained using raw TEM data (with birdswing removal) and TEM data obtained by postprocessing using time-consuming empirical corrections based on the TEM half-space response over deep sea water. The interpreted sediment depths derived from TEM and marine seismic data showed good agreement, generally, for example, inversion of TEM data delineated a distinct palaeovalley that transects a beach, with a maximum depth of 60–70 m below the seafloor, in agreement with depths estimated from marine seismic data to within [Formula: see text].
2D joint inversion of RMT and ERT data versus individual 3D inversion of full tensor RMT data: An example from Trecate site in Italy
Authors: Bastani Mehrdad , Hübert Juliane , Kalscheuer Thomas , Pedersen Laust B. , Godio Alberto , Bernard Jean 
Published: July 2012

Tensor radiomagnetotelluric (RMT) and electrical resistivity tomography (ERT) data were acquired along 10 parallel lines to image electrical resistivity of the vadose and the saturated zone in an area near Trecate, 45 km west of Milan in Italy. In 1994, the area was exposed to an oil contamination caused by a tank explosion and has since been subject to monitoring and remediation programs. For the first time, we have examined a 3D inversion of full tensor RMT data and have compared the results with 2D joint inversion of RMT and ERT data. First, a synthetic 3D resistivity model with similar variations close to those measured at the Trecate site was generated for the comparison. The synthetic tests showed that resistivity models from 2D joint inversion of ERT and RMT data contain more details closer to the surface compared to the models from the 3D inversion of tensor RMT data. High resistivity structures are better resolved by the 2D joint inversion, whereas the more conductive features are better recovered by the 3D inversion. In the next step, the ERT and RMT data collected in the Trecate site were modeled with the same approaches used in the synthetic modeling. Using the measured tensor RMT data, it was possible to carry out full 3D inversion to study the underlying geology. Comparison between the resistivity models from both inversions with the lithological data from the existing boreholes, resistivity models from the inversion of crosshole resistivity data, and water content models from magnetic resonance soundings measurements showed that the electrical resistivity, depth to the top and thickness of the water saturated zone is modeled more accurately with the 3D inversion.
Nehanda and Gender Victimhood in the Central Mashonaland 1896–97 Rebellions: Revisiting the Evidence
Authors: Charumbira Ruramisai 
Published: July 2012

In 1998 David N. Beach revisited the 1896-97 central MaShonaland rising in colonial Zimbabwe in an article titled “An Innocent Woman Unjustly Accused? Charwe, Medium of the Nehanda Mhondoro Spirit, and the 1896-97 Central Shona Rising in Zimbabwe.” Beach's main thesis was that, contrary to conventional wisdom that placed Nehanda-Charwe (and other leaders) at the center of those anti-European settler rebellions, Nehanda-Charwe might have been “an innocent woman unjustly accused.” For Beach, upstart Kaguvi-Gumboreshumba (a male spiritual leader) might have been the real hero, for he was to be found in all the sources and his tracks were better traceable than Nehanda-Charwe, who had a sporadic presence in the same sources.Since Beach's 1998 study, I have not come across any other original study that has extended or disputed his arguments; to that end, I consider this study a response to Beach's study and an invitation to revisit the historiography of early colonial Zimbabwe through feminist lenses. My main aim is to revisit two major issues Beach raised in his study, and to look at them through a feminist lens in order to understand whether Nehanda-Charwe was indeed an “innocent woman unjustly accused” or whether something else was at play. After giving a brief background to the rebellion in MaShonaland, I will look at the issue of the credibility of evidence given by Africans to colonial officials about those who were up in arms against the colonial authority, the British South Africa Company (BSAC), with a focus on women's testimonies.
Finding Bosutswe: Archeological Encounters with the Past
Authors: Denbow James , Mosothwane Morongwa , Ndobochani Nonofho Mathibidi 
Published: July 2012

Bi-lingual, Bi-culturalable to slip from “How's life”to M'estan volviendo loca,able to sit in a paneled officedrafting memos in smooth English,able to order in fluent Spanishat a Mexican restaurant,American but hyphenated,viewed by Anglos as perhaps exotic,perhaps inferior, definitely different,viewed by Mexicans as alien(their eyes say, “You may speakSpanish but you're not like me”)an American to Mexicansa Mexican to Americansa handy tokensliding back and forthbetween the fringes of both worldsby smilingby masking the discomfortof being pre-judgedBi-laterally.This paper presents a micro-scale examination of archeological field praxis and its impact on archeologists, students (foreign and indigenous), and the local communities that both host and labor for them. It is a reflexive journey that attempts to bring coherence to the multiple and changing registers of meaning, contradiction, and transformation that have taken place during excavations at Bosutswe in “post-colonial” Botswana. We discuss our interactions with one another and our encounters with “the past” as we sought to validate, transform, or escape the contemporary entanglements of multilateral “pre-judgments” that have their roots deep in the soil of colonial encounter.Pat Mora in her short poem, Two Worlds, captures some of the contradictions inherent in a post-modern, post-colonial, transnational world, where one is sometimes offered the possibility of inhabiting multiple universes, with multiple cultural and linguistic positionalities, and sometimes even trans-ethnic or transnational identities as possible choices.
Existing and New Coating Technologies for Drilling and Completion Applications
Authors: Lauer R. S. 
Published: July 2012

Abstract
Historically, internal coatings have been used primarily to successfully mitigate corrosion in drill strings. Advancements in technology have improved the performance of these materials leading to much longer life expectancies as well as the expansion of their use into other areas of the market. These newer systems are now finding their way into more aggressive completion operations where the use of coatings was largely not accepted due to fears of coating damage. With new abrasion resistant systems coming out on the market, successes are now being seen in cementing, the pumping of gravel packs, fracing, acidizing as well as other mechanical interventions. This paper will discuss several significant recent applications:
17 completions in which numerous acid treatments were performed in conjunction with multiple frac packs. The majority of this work was performed in wells with deviations from 23° to a maximum of 75°. Inspections performed on this string include electromagnetic inspection of the pipe body as well as a magnetic particle inspection on the tool joints. The results of these inspections indicated that not one single joint was downgraded due to internal corrosion or wall loss. These results are particularly impressive considering this pipe was made up and broken out a total of 150 times. A comparison in the performance of an internally bare string and then a string internally coated with a modified epoxy-phenolic coating being subjected to numerous cementing operations. Even though the pipe was used and pitted, prior to the initial coating, repeated uses did not cause adverse damage to the coating and did not allow further corrosion to take place on the ID surface.
Lastly, there are new coating materials being introduced into the market that improve upon existing technologies. These materials will provide even greater abrasion resistance, chemical resistance and possess greater flexibility and toughness allowing them to succeed in even the harshest of applications such as deepwater and extended reach completions.
Application of Down-hole Screw-type Pressure Intensifier for ROP Enhancement
Authors: Meishan Wang , Jun He , Yong He , YI Xu , Jian Zhao 
Published: July 2012

Abstract
Down-hole Screw-type Pressure Intensifier is a new ROP enhancement device, using helicoid hydraulic motor as the power. It can convert the rotation movement of the helicoid hydraulic motor into the reciprocating movement of the piston pump through a special spiral cant type reversing mechanism, thus some part of the total drilling fluid can be pressurized to more than 100 MPa and erupt out from the ultra high pressure nozzles installed in PDC bit. The high pressure water assisting the rock breaking was implemented by this device and the rock breaking efficiency was improved.
This new down-hole pressure intensifier has been tested and used in 2 wells situated in Jilin oilfield, Songliao basin. The hole depth was from 1967m to 2355m, and the bit size was 9-1/2in. The Down-hole Screw-type Pressure Intensifier worked for 70hrs, and increased the rate of penetration by 52.4% and 95.3% compared with the adjacent wells. Result of the applications shows that the Down-hole Screw-type Pressure Intensifier is structured reasonably, be cable of working for more than 100hrs and has increasd the rate of penetration remarkably. The success of this tool's field application might provide a way to increase the rate of penetration in hard and complex layers, shorten well construction period, and reduce the drilling cost.