bluuebunny/crossref_metadata_2025 huggingface dataset:
Evolution of Horizontal Well Hydraulic Fracturing in the Granite Wash – Understanding Well Performance Drivers of a Liquids-Rich Anadarko Basin Formation
Authors: Srinivasan K. , Dean B. , Belobraydic M. , Azmi Z.
Published: February 2013

The multi-zone Granite Wash is a mature vertical well play extending across 6 counties in the Texas Panhandle and Western Oklahoma. The laterally and vertically extensive formations were developed with close spaced vertical wells for several decades. In the last five years, almost all development has been horizontal, initially adapting drilling and completion technologies from shale gas development. With over 200 million barrels of proven Granite Wash reserves and low US natural gas prices, Anadarko basin E & P efforts are migrating towards higher rates of return from Granite Wash light oil, gas condensate and natural gas liquids. Driven by horizontal drilling and modern completion and fracturing techniques, horizontal well count and hydrocarbon liquid production have more than tripled over the last 4 years in this active U.S. mid-continent play.

Unlike typical sandstone reservoirs, the Granite Wash has complex mineralogy including quartz, potassium and sodium feldspars, illite, chlorite, dolomite and calcite. Depositional environments range from near shoreline to continental slope events to deep marine. Many of the targets consist of compartmentalized sub-marine fan deposition. Due to high level of reservoir heterogeneity and GOR, it is difficult to characterize reservoir property changes between fields and horizons. Prior production driver studies on vertical wells in the Granite Wash did focus on both reservoir and completion parameters. The bulk of horizontal studies are limited to completions and stimulation without rigorous investigation of stratigraphic and reservoir quality variation. This paper correlates well performance with completion and fracturing practices in well samples of similar geographic and stratigraphic position, determined from public domain well, completion and well and log data.

Using the large enormous public database of vertical wells, a three-dimensional sub-surface model of the reservoir is built for three geographic areas with multiple stratigraphic benches to reduce sample variation of reservoir quality. Reservoir quality is defined from petrophysical properties that affect the productivity of the well including but not limited to porosity, permeability, saturations and rock mineralogy, and accordingly, property distribution models are built for each property across study areas. Stimulation parameters investigated include, but are not limited to lateral length, number of fracturing stages, and normalized fluid and proppant volumes. Reservoir quality from the three dimensional model and parameters from the stimulation database are then correlated with well production to identify both stimulation and reservoir production drivers. The result sought is improved conclusions and recommendations for completion and stimulation in specific geographic areas and stratigraphic benches.
Revisiting the Before Closure Analysis Formulations in Diagnostic Fracturing Injection Test
Authors: Lamei H. , Soliman M. Y. , Shahri M.
Published: February 2013

The before closure analysis (BCA) method describes the unsteady flow of fracturing fluid into a formation considering time-dependent fracture face resistance. It provides a methodology for calculating the permeability and fracture face resistance instead of calculating the conventional leakoff coefficient. The original BCA model developed by Mayerhofer et al. (1995) has been simplified by different authors, including Valkó and Economides (1999). It is found that their proposed simplified formulation has some inconsistencies, which results in erroneous analysis of data and interpretation of permeability.

In this paper, the inconsistencies in the formulation have been addressed and resolved. The formulation of the corrected model is presented in a complete fashion. A discussion on sensitivity of the analysis, effect of pressure-dependent permeability, height recession, tip extension, and the effect of the reservoir fluid type is also provided. To validate the approach, two field examples of conventional oil reservoirs are presented as well. In the second case, the results are compared to the after closure analysis (ACA), and the effect of normal leakoff and pressure- dependent leakoff (PDL) on the BCA plot is discussed. The importance of considering correct data points in a normal leakoff portion is shown and illustrated on a BCA plot.
Thermal Reactivation of Microfractures and its Potential Impact on Hydraulic Fractures Efficiency
Authors: Dahi Taleghani A. , Olson J. E. , Wang W.
Published: February 2013

Core studies have proven the presence of abundant cemented micro-fractures in many tight formations. Furthermore, these studies have revealed the opening of some of these microfractures on the wall surface of main hydraulic fractures. Additionally, early-production well-testing analysis in some of these cases provides estimates for hydraulically induced fracture surface area which is much larger than fracture dimensions estimated in fracturing design or provided by the location of microseismic events. Existence of open small-size fractures could be a possible cause behind this discrepancy. In this paper, we show in what extent thermal stresses induced by temperature difference between fracturing fluid and formation fluid could provide the driving force to open a portion of these small cemented natural fractures laying on the surface of hydraulic fractures. Moreover, through combination of stress analysis and empirical fracture distribution models obtained from outcrops, we calculate the increase of total reservoir/fractures contact surface under the condition of microfractures activation. Our thermoelasticity analysis reveals the effect of the pump rate and temperature of the fracturing fluid on the number of activated microfractures. The results show that the volume of the micro-fractures varies depending on the length of the microfracture, rock properties and time. At the end, through an example, we show that activation of only a small portion of these microfractures can increase the total formation contact surface considerably and consequently initial production. Reservoir pressure changes due to production might partially close or re -open these micro-cracks during production. Hence, the role of these microfractures is mainly restricted to the early life of the reservoirs.
Utilization of Microseismic Event Source Parameters for the Calibration of Complex Hydraulic Fracture Models
Authors: Downie Robert , Xu Jian , Grant Dee , Malpani Raj , Viswanathan Anup
Published: February 2013

Observations of microseismic events detected during hydraulic fracturing treatments have provided an incentive to develop complex fracture models. Calibration of these models can be difficult when only the locations and times of the microseismic events are used. Incorporating the microseismic event source parameters into the model calibration workflow reveals changes in fracture behavior that are not easily visualized and provides additional guidance to the selection of modeling parameters.

Microseismic events occur when deformation of the reservoir and surrounding formations produces seismic waveforms. Travel-time and hodogram analysis of the recorded waveforms are used to locate the microseismic event sources while the amplitudes and polarities of the waveforms provide information about the deformation that has occurred. The geophysical property that is derived from the wave amplitudes is known as the seismic moment and is related to the area and displacement of the failure.

The relationship between seismic moment values and the deformations that produced microseismic events can be applied to engineering evaluations to identify variations in microseismic response. Use of this source parameter supplements commonly used visualizations of microseismic response where microseismic activity has been mapped. An example from a field case is included.

Mapping of the seismic moment distributions in a 3-dimensional viewer provides insights into fracture behavior that can be used to calibrate complex hydraulic fracture models. This is done through an integrated software package that facilitates comparisons of the microseismic evaluation and complex fracture modeling outputs seamlessly. Changes to the complex fracture model inputs can be evaluated quickly and easily to determine if the fracture modeling correlates well with the measured microseismic responses. Production evaluation, history-matching, and forward-modeling to test different completion and stimulation design scenarios can be undertaken with improved confidence using the calibrated complex fracture model.
Reducing the sensitivity of the water quality index to episodic events
Authors: Kilgour Bruce W. , Francis Anthony P. , Mercier Vincent
Published: February 2013

We demonstrated a general relationship between water quality index (WQI) values and indices of benthic community composition for a set of 32 streams from British Columbia and Ontario. Streams that produced lower WQI values tended to have benthic communities characteristic of degraded water quality. Streams, in contrast, that produced higher WQI scores tended to have a fauna characteristic of high water quality. Trimming the water quality data for high-total suspended solids (TSS) events increased the WQI values by as much as 30 points. There were modest but apparent increases in the strength of the association between the WQI and indices of benthic community composition when the water quality data records were trimmed of values that occurred during periods of high (extreme) turbidity. Trimming data that contained turbidity (or TSS) values beyond the mirrored 5th, 90th, or 95th percentile were about equal in their effect on the WQI. The removal of high TSS samples on the basis of the ‘mirror’ method can be recommended on the basis that it will likely correctly remove data that have a long right-hand tail, and will also correctly not remove data when the data are more normally distributed.
Review of swimming-associated cryptosporidiosis and Cryptosporidium oocysts removals from swimming pools
Authors: Lu Ping , Yuan Tao , Feng Qiyan , Xu Aiqin , Li Jiayuan
Published: February 2013

In this paper, outbreaks of cryptosporidiosis in swimming pools in the last 20 years are summarized. Cryptosporidium oocysts are very resistant to many disinfectants, including chlorine, one of the most widely-used disinfectants in swimming pools. Ozone or UV is shown to inactivate Cryptosporidium, while not effective to newly introduced Cryptosporidium and bacteria because of no residual ozone or UV in the treated swimming pool water. Additionally, swimming pool sand filters or cartridge filters are not able to effectively remove Cryptosporidium (removal rate <50%). Above 99% Cryptosporidium removals are achieved in drinking water treatment, but swimming pool water treatment is different from drinking water treatment: no coagulation is performed prior to filtration in most US swimming pools, filtration rate is four to five times higher for swimming pool water treatment compared with drinking water treatment, and the input compounds and microorganisms from bathers continuously recirculate in the swimming pool. Moreover, up-to-date Cryptosporidium or Cryptosporidium surrogate removals from swimming pools are discussed, and alternative swimming pool treatment techniques are reviewed.
A Six-Year Follow-up Study of Social Network Changes among African-American, Caribbean, and U.S.-Born Caucasian Urban Older Adults
Authors: Conway Francine , Magai Carol , Jones Samuel , Fiori Katherine , Gillespie Michael
Published: February 2013

This study explores dynamic changes in network size and composition by examining patterns of older adults' social network change over time, that is: types of movements; the reason for the loss of network members; and the relation of movement and composition in concert. This study is a 6-year follow up of changes in the social networks of U.S.-Born Caucasian, African-American, and Caribbean older adults. One hundred and twenty-four community-dwelling older adults were interviewed during 2 data collection points over a 6-year period. Differences between Wave 1 and Wave 2 data were examined using paired sample t-tests confirmed with post-hoc tests and multivariate analyses. Results regarding types of movement showed that network changes were attributed to attrition—the “loss” of network members and a novel movement—the “addition” of network members not heretofore discussed. The results show an interaction between kinship status, ethnicity, and time—the attrition of non-kin members was underscored by ethnic differences. The type of network change was specific for type of network affiliation, such that children were more likely to be added to the networks of the young-old and kin were more likely to be lost in networks of the old-old. Older adults engage in social network interactions marked by compensatory processes beyond loss of network members such as social promotion and demotion. These social network processes are of emotional and functional significance for the older adult.
Forgiving and Feeling Forgiven in Late Adulthood
Authors: Torges Cynthia , Ingersoll-Dayton Berit , Krause Neal
Published: February 2013

Enright and colleagues (1996) emphasized the beneficial effect of experiencing forgiveness across multiple domains. We build upon their conceptualization of forgiveness by adding a domain—forgiveness by God—to create global forgiveness. In the current study, we use data from a nationally representative study, the Religion, Aging and Health Survey, which utilizes the responses of 1208 Blacks and Whites. The results from a latent variable model indicated that both Blacks and women were more likely to participate in organized religion, and this participation was associated with feeling closer to God. In turn, feeling closer to God corresponded to higher levels of global forgiveness but was not directly associated with improved well-being. Instead, it was global forgiveness that mediated the relationship between closeness to God and improved well-being.
Walking the Red Road: The Role of First Nations Grandparents in Promoting Cultural Well-Being
Authors: Thompson Grace E. , Cameron Rose E. , Fuller-Thomson Esme
Published: February 2013

The purpose of this grounded theory study was to provide a framework for understanding the contemporary experience of First Nations grandparents. Fifteen respondents ( N = 15) were selected from two demographically different Canadian cities. Seven of the grandparents lived with their child and a grandchild or grandchildren at the time of the interview; an additional four had lived with their grandchildren at some point prior to this investigation. Results revealed that First Nations grandparents had leveraged their own experiences of cultural disruption to reinvest in the cultural health and well-being of their grandchildren. One grandfather described this role as “walking the red road” which entailed a responsibility “to provide wisdom and … protection.” Identified benefits of rejuvenating traditions and grandparent involvement included cultural healing and joy.
Modeling intraparticle transports during propylene polymerizations using supported metallocene and dual function metallocene as catalysts: Single particle model
Authors: Li Hua-Rong , Che Liming , Luo Zheng-Hong
Published: February 2013

Two improved multigrain models (MGMs) for preparing homopolypropylene and
long chain branched polypropylene via propylene polymerization using
silica-supported metallocene or dual function metallocene as catalysts are
presented in this paper. The presented models are used to predict the
intraparticle flow fields involved in the polymerizations. The simulation
results show that the flow field distributions involve dare basically
identical. The results also show that both the two polymerization processes
have an initiation stage and the controlling step for them is
reaction-diffusion-reaction with the polymerization proceeding. Furthermore,
the simulation results show that the intra particle mass transfer resistance
has significant effect on the polymerization but the heat transfer resistance
can be ignored.
Urea intercalation compound production in industrial scale for paper coating
Authors: Zhu Xiaoyan , Chen Jianchao , Chen Jieyu , Lei Xinrong , Yan Chunjie
Published: February 2013

Urea intercalation compounds were produced in a new designed industrial
scale. The conditions and locations of the new industrial process for the
production of urea intercalation compound pigment were studied through the
control of correlative parameters. Properties of the compound pigment such as
particle morphology, particle size distribution and viscosity, were analyzed
to evaluate its potentiality for paper coating application. Results showed
that the intercalation ratio of urea intercalation compound increased from
6.3% with 2wt. % of urea addition to 56.08% with 6wt.% of urea addition.
Viscosity concentration of urea intercalation compound improved from 69% of
original kaolinite to the highest value, 74.23% of the compound. Particle
size distribution was centralized. Properties of light weight papers coated
with urea intercalation compound showed interesting results, similar to a
standard grade.
DESIR high resolution separator at GANIL, France
Authors: Toprek Dragan , Kurtukian-Nieto Teresa
Published: February 2013

A high-resolution separator for the SPIRAL2/DESIR project at GANIL has been
designed. The extracted isotopes from SPIRAL2 will be transported to and
cooled in a RFQ cooler yielding beams with very low transverse emittance and
energy spread. These beams will then be accelerated to 60 keV and sent to a
high-resolution mass separator where a specific isotope will be selected. The
good beam properties extracted from the RFQ cooler will allow one to obtain a
mass resolution of c26000 with the high-resolution mass separator.
Age-related structural changes in the myenteric nervous plexus ganglion along the anterior wall of the proximal human duodenum: A morphometric analysis
Authors: Mandic Predrag , Lestarevic Snezana , Filipovic Tatjana , Djukic-Macut Natasa , Saranovic Milena
Published: February 2013

Background/Aim. Aging is one of the most complex biological processes which
probably affect structure and function of the enteric nerve system. However,
there is not much available information on this topic, particularly in
humans. The aim of this study was to investigate the influence of aging on
the structure of the myenteric ganglia in the anterior wall of the human
proximal duodenum. Methods. We examined the myenteric ganglia in the proximal
duodenal anterior wall specimens obtained from 30 cadaver persons aged from
20 to 84 years. Tissue samples were classified into three age groups: 20-44,
45-64 and 65-84 years. After standard histological preparation, specimens
were stained with HE, Cresyl Violet and AgNO3. Morphometric analysis of all
the specimens, using a multipurpose test system M42, was performed. The data
were subjected to the ttest. Results. The myenteric ganglia of very old
humans contains an empty space, i.e. the respective parts of ganglia show a
decreased number of neuron as compared to younger population. The average
number of neuron per cm2 of the duodenum in the youngest people (20-44 years)
was 69,370 ? 1,750.00, in the people aged 45-64 years 69,211 ? 1,573.33, and
in the oldest persons (65-84 years) 57,951 ? 1,291.52. The loss of neurons in
the oldest persons was 16.46%. The applied statistic test demonstrated a
significant difference between the observed groups (p < 0.0001). Conclusion.
Aging does not induce changes in size and surface of neurons in the ganglia,
but it decreases the number of neurons. The nerve structures in the elderly
are partly emptied of bodies of nerve cells (?empty ganglions?), which
indicates the existence of changed myenteric ganglia in the duodenum. These
changes could be related to the duodenum motility disorder associated with
aging.
The Role of Accounting Conservatism in the Equity Market: Evidence from Seasoned Equity Offerings
Authors: Kim Yongtae , Li Siqi , Pan Carrie , Zuo Luo
Published: February 2013

Using seasoned equity offerings (SEOs) from 1989 to 2008, we examine the role of accounting conservatism in the equity market. We find that issuers with a greater degree of conservatism experience fewer negative market reactions to SEO announcements. We further show that an important mechanism through which conservatism affects SEO announcement returns is by mitigating the negative impact of information asymmetry. Additional analyses suggest that our results are not driven by the effects of other forms of corporate governance. We also find evidence that conservative issuers continue to use conservative accounting after the equity offerings. Taken together, our findings are consistent with the argument that accounting conservatism reduces financing costs in SEOs.

Data Availability: Data used in this study are available from public sources identified in the study.
Hypofractionated stereotactic radiotherapy for large or involving critical organs cerebral arteriovenous malformations
Authors: Blamek Sławomir , Larysz Dawid , Miszczyk Leszek , Idasiak Adam , Rudnik Adam , Tarnawski Rafał
Published: February 2013

Background. The treatment of large arteriovenous malformations (AVMs) or AVMs involving eloquent regions of the brain remains a challenge. For inoperable lesions, observation, volume-staged radiosurgery or hypofractionated stereotactic radiotherapy (HFSRT) are proposed. The aim of our study was to assess the safety and efficiency of HFSRT for large AVMs located in eloquent areas of the brain.

Materials and methods. An analysis of records of 49 patients irradiated for cerebral AVMs with a mean dose of 19.9 Gy (12-28 Gy) delivered in 2-4 fractions with planned gap (at least one week) between fractions. Actuarial obliteration rates and annual bleeding hazard were calculated using Kaplan-Meier survival analysis and life tables. Results. Annual bleeding hazard rates were 4.5% and 1.6% after one and two years of the follow-up, respectively. Actuarial total obliteration rates were 7%, 11%, and 21% and total response rate (total and partial obliterations) 22%, 41%, and 55% after one, two and three years of the follow-up, respectively. There was a trend towards larger total obliteration rate in patients irradiated with fraction dose ≥ 8 Gy and total dose > 21 Gy for lesions of volume ≤ 8.18 cm3 which was not observed in case of partial obliterations.

Conclusions. HFSRT results with relatively low obliteration rate but is not associated with a significant risk of permanent neurological deficits if both total and fraction doses are adjusted to size and location of the lesion. Predictive factors for total and partial obliterations can be different; this observation, however, is not firmly supported and requires further studies.
Dangerous disciplines: Understanding pedagogies of punishment in the neoliberal states of America
Authors: Robbins Christopher G. , Kovalchuk Serhiy
Published: February 2013

Public schools deploy a range of processes and practices that help constitute the formation and legitimation of certain knowledges, relationships, skills, values and, ultimately, subjectivities. School discipline regimes are one of these practices. Exercising their power through pedagogical modes of address, these regimes are currently organizing relationships throughout school cultures that reflect the values and encourage role performances associated with neoliberal capitalism. This research paper describes and analyzes two widely used discipline regimes-zero tolerance/hyper-criminalization and positive behavior interventions and support (PBIS) -through Foucault’s theories of governmentality and biopolitics. These two regimes provide mirror images of the primary modes of punishing and disciplining under neoliberalism: criminalization and individualization. The paper will also explore how neoliberalism subjects schools to processes of enclosure, but also how schools themselves have become sites productive of neoliberal subjects through the content, values and interests embedded in the curricula of PBIS and criminalization which students must master.
Post-Social politics, employability, and the security effects of higher education
Authors: Frauley Jon
Published: February 2013

Trends within Western capitalist societies toward the individualizing of social problems, the responsibilizing of individuals for such problems, the treating of social problems as problems of control, ongoing attempts to shift the burden for safety and security from the state to the market, and changing conceptions of citizenship, have produced a context within which economic insecurity appears as a governable problem for higher education. Canada’s most populous province, Ontario, experienced radical education reforms during the “common sense revolution” of the Progressive Conservative government from 1995 to 2003. The paper examines government documents, committee and task force reports, and legislative debates and hearings pertaining to these restructuring efforts and draws on the work of Michel Foucault and political sociology to explore the ‘security effects’ of higher education and the latter’s conceptual relationship to employability. Higher education policy and restructuring, shaped as it is by human capital theory, takes employability to be an outcome of restructuring. However, as the paper shows, in an attempt to produce ‘security effects’, employability operated as a central and constitutive category of governance around which education policies as regulatory strategies were crafted. In the recent emergence of a ‘next step’ in the production of the security effects of education employability is displaced by innovation.
Being different and the same? The paradoxes of ‘tailoring’ in education quasi - markets
Authors: Savage Glenn C.
Published: February 2013

In Australia, market-based education policies promote the notion that government schools should flexibly tailor secondary education to the needs of young people and their local communities. Far from offering a “one size fits all” system, policies seek to enable clients (parents, students) to exercise freedom of choice in quasi-markets that offer different educational products to different individuals. The intended effect is a kind of bespoke education tailoring, whereby schools operate as flexible service providers, adapting to the needs and desires of local markets. In this paper, I analyse the policy turn towards market tailoring as part of broader shifts towards advanced liberal governance in education. Following this, I feature interviews with educators in two socially disparate government secondary schools in the Australian city of Melbourne. In doing so, I analyse the extent to which each school tailors its marketing practices to its local community. These interviews suggest inherent contradictions emerge when tailoring is attempted in a hierarchical market with normative and rigid indicators of ‘brand value’. Schools are caught, I argue, between paradoxical demands, requiring them to be simultaneously different and the same.
Physical Culture in the Tradition and Rites of the Tatar Population Inhabiting Polish Territory
Authors: Szum Ernest , Cieoeliński Ryszard
Published: February 2013

This report presents the findings of a qualitative study on the physical culture of the Tatar community inhabiting Polish territory. Historical elements of the physical culture of the Tatar community have been presented against the background of general characteristics of this ethnic group and the history of the presence of Tatars on Polish soil. The article shows particular aspects of the Tatar tradition of physical culture and its place in Tatar national culture. This is the first known report on the physical culture of this ethnic group on the ground of ethnology or cultural anthropology.
Time Series Approach To Athletes Motor Potential
Authors: Maszczyk Adam , Roczniok Robert , Pietraszewski Przemysław , Stanula Arkadiusz , Zając Adam , Gołaś Artur
Published: February 2013

Introduction
. The aim of this study was to determine the dynamics of changes in selected motor abilities of javelin throwers and to determine predictors of javelin throw distances.
Material and methods
. Research material included the results obtained from a group of 60 competitors from the Silesia Region of Poland, aged 14 - 15 years. In order to answer the research question, the following statistical analysis were employed: Pearson's linear correlation coefficients, vectors R0 and R1, time series analysis, distributed lag analysis and Almon distributed lag analysis and coefficient of concordance φ2

Results
. The correlation analyzes allowed for a selection of two variables for further analyses: specific strength of arms and trunk (SSAT) and specific strength of shoulders girdle and trunk (SSGT). Calculated indexes revealed that the level of SSAT showed a constant upward tendency (+15%). The highest rise in SSAT level was recorded in the 4th and 5th quarter (+9%). The level of SSGT showed an upward tendency nearly (+6%). In this case, the highest rise was observed in the 7th and 8th quarter (+4.5%).
Conclusions
. The standardized regression analysis revealed that the variable of specific power of arms and trunk (SOBT) is the most important predictor for javelin throw distance with a full approach run.
It Will/Must/May Be a Modal Auxiliary
Authors: Ilc Gašper
Published: February 2013

The English modal verb system has proved to be a difficult linguistic concept even for advanced EFL students. Their comprehension/usage problems may be of purely morpho-syntactic and semantic nature or may also involve sociolinguistic dimensions. The paper examines the question of polysemy, sociolinguistic factors and the role of ELT models.
Alienation in Caryl Churchill’s a Number
Authors: Anghel Florentina
Published: February 2013

Caryl Churchill’s play A Number echoes the author’s attitude towards scientific evolution, having as a result cloning, and its impact on social and moral values and relationships. The paper will focus on identitary problems raised by cloning, on the clash between uniqueness and seriality, on the confusion arising from opportunities and unexpected effects.
Daniel Martin’s Multiple Journeys
Authors: Coser Cornelia
Published: February 2013

Modern literature modifies the pattern on which most western narration was founded. The hero’s adventures come to exhibit the same dependence on initial conditions as dynamical systems do. In John Fowles’s novel, Daniel Martin, both character and author benefit from multiple journeys, the fractal characteristics of the novel standing in contrast with the wholeness of the vision.
Off the Beaten Path: Ella D'arcy's Yellow Book Stories
Authors: Doroholschi Claudia Ioana
Published: February 2013

The small body of work produced by Ella D’Arcy in the 1890s is noteworthy for its experimentation with narrative instability, its unsympathetic treatment of character and its oppressive, claustrophobic fictional world. The paper looks at how D’Arcy’s fiction makes use of shifts in focalisation, melodramatic plot twists and closure to build up a sense of irresoluteness and moral de-centering.
Reconstructing a Life: Charles ‘Buddy’ Bolden
Authors: Dumescu Patricia-Dorli
Published: February 2013

Michael Ondaatje’s novel Coming through Slaughter is a fascinating attempt to bring literature and oral history together in order to recreate Charles ‘Buddy’ Bolden’s mysterious life. Daily routines and gestures, inner thoughts and high musical notes form a puzzle to which the citizens of the flamboyant New Orleans keep adding pieces. With the help of his only existing photograph, the present paper focuses on the unquestionable father of jazz, who kept “away from recorded history”.
Diagnostic Accuracy of Clinical Tests for Assessment of Hamstring Injury: A Systematic Review
Authors: Reiman Michael P. , Loudon Janice K. , Goode Adam P.
Published: February 2013

Study Design

Systematic literature review.

Background

The diagnosis of a hamstring injury has traditionally relied on various clinical measures (eg, palpation, swelling, manual resistance), as well as the use of diagnostic imaging. But a few studies have suggested the use of specific clinical tests that may be helpful for the diagnostic process.

Objective

To summarize the current literature on the diagnostic accuracy of orthopaedic special tests for hamstring injuries and to determine their clinical utility.

Methods

A computer-assisted literature search of the MEDLINE, CINAHL, and Embase databases (along with a manual search of grey literature) was conducted using key words related to diagnostic accuracy of hamstring injuries. To be considered for inclusion in the review, the study required (1) patients with hamstring or posterior thigh pain; (2) a cohort, case-control, or cross-sectional design; (3) inclusion of at least 1 clinical examination test used to evaluate hamstring pathology; (4) comparison against an acceptable reference standard; (5) reporting of diagnostic accuracy of the measures (sensitivity [SN], specificity [SP], or likelihood ratios); and (6) publication in English. SN, SP, and positive and negative likelihood ratios were calculated for each diagnostic test.

Results

The search strategy identified 602 potential articles, of which only 3 articles met the inclusion criteria, with only 1 of these 3 articles being of high quality. Two of the studies investigated a single special test, whereas the third article examined a composite clinical assessment employing various special tests. The SN values ranged from 0.55 (95% confidence interval [CI]: 0.46, 0.69) for the active range-of-motion test to 1.00 (95% CI: 0.97, 1.00) for the taking-off-the-shoe test. The SP values ranged from 0.03 (95% CI: 0.00, 0.22) for the composite clinical assessment to 1.00 (95% CI: 0.97, 1.00) for the taking-off-the-shoe test, active range-of-motion test, passive range-of-motion test, and resisted range-of-motion test. The use of a single special test demonstrated stronger SP than SN properties, whereas the composite clinical assessment demonstrated stronger SN than SP properties.

Conclusion

Very few studies have investigated the utilization of clinical special tests for the diagnosis of hamstring injuries. Further studies of higher quality design are suggested prior to advocating independent clinical utilization of these special tests.

Level of Evidence

Diagnosis, level 3b. J Orthop Sports Phys Ther 2013;43(4):222–231. Epub 14 January 2013. doi:10.2519/jospt.2013.4343
Quantity and Quality of Physical Activity Are Influenced by Outdoor Temperature in People with Knee Osteoarthritis
Authors: Robbins Shawn M. , Jones Gareth R. , Birmingham Trevor B. , Maly Monica R.
Published: February 2013

Purpose: Environmental factors are known to influence physical activity (PA) levels of healthy people, but little work has explored these factors in people with osteoarthritis (OA). The purpose of this study was to explore the influence of outdoor temperature on PA in people with knee OA. Methods: A total of 38 people with knee OA (10 women; mean age 54 y) wore an accelerometer around their waist for 7 consecutive days. Dependent variables from the accelerometers were three PA measures: (1) activity counts/day and time spent at or above moderate levels of PA with (2) a cut-point of 1,041 activity counts/minute (MVPA1041) and (3) a cut-point of 1,952 activity counts/minute (MVPA1952). Independent variables were age, sex, body mass index (BMI), and maximum daily outdoor temperature. Three linear regression analyses were conducted using the three PA dependent variables and independent variables. Results: After controlling for age, sex, and BMI, maximum daily outdoor temperature explained 9% of the variance in activity counts/day (p=0.042), 10% of variance in MVPA1041(p=0.032), and 14% of variance in MVPA1952(p=0.016). Participants who engaged in more PA were younger and were exposed to warmer temperatures. Conclusions: Outdoor temperature and age influence the PA levels of people with knee OA. These factors should be considered when designing PA programmes.
Influence of snow type and temperature on snow viscosity
Authors: Delmas Louis
Published: February 2013

Three spontaneous avalanches were observed in Lia, Longyearbyen, Svalbard, each occurring naturally under similar temperature conditions. Automatic measurements of temperature inside the snowpack led to examination of the triggering of avalanches in cold conditions following a rapid drop in temperature. The mechanical properties of ice depend on the slab temperature and I ask: could a rapid temperature change affect the mechanical properties differently considering a slab consisting of (1) rounded grains or (2) faceted grains? Snow is considered as a foam of ice crystals, and triaxial deformation tests are performed at constant strain rate to examine the influence of temperature and grain type on the mechanical properties. Although the snow densities in the two sample sets were almost identical, some differences due to grain type were observed. In particular, the set with faceted grain snow started to flow at higher stresses than the set with rounded grains.
Recent Advances in Multi-Drug Resistance (MDR) Efflux Pump Inhibitors of Gram-Positive Bacteria S. aureus
Authors: Handzlik Jadwiga , Matys Anna , Kieć-Kononowicz Katarzyna
Published: February 2013

The paper focuses on recent achievements in the search for new chemical compounds able to inhibit multidrug resistance (MDR) mechanisms in Gram-positive pathogens. An analysis of the results of the search for new efflux pump inhibitors (EPIs) for Gram-positive bacteria, which have been performed over the last decade, indicates that almost all efforts are focused on the NorA (MFS) efflux pump in S. aureus. Considering the chemical structures of the NorA EPIs that have been identified, it can be observed that the most active agents belong to the families of compounds possessing conjugated double bonds, e.g., chalcones, piperine-like compounds, N-cinnamoylphenalkylamides or citral amide derivatives. Indole-, dihydronaphthyl-, 2-chloro-5-bromo-phenyl- or piperidine moieties seem to be profitable for the EPI properties, as well. These results, together with an increasing knowledge about a variety of efflux pumps that are involved in MDR of Gram-positive pathogens underline that further search for new EPIs should pay more attention to develop MDR efflux protein targets, including SMR, MATE, ABC or other members of the MFS family.
Nonstandard Approach to Gravity for the Dark Sector of the Universe
Authors: Stichel Peter , Zakrzewski Wojtek
Published: February 2013

We summarize the present state of research on the darkon fluid as a model for the dark sector of the Universe. Nonrelativistic massless particles are introduced as a realization of the Galilei group in an enlarged phase space. The additional degrees of freedom allow for a nonstandard, minimal coupling to gravity respecting Einstein’s equivalence principle. Extended to a self-gravitating fluid the Poisson equation for the gravitational potential contains a dynamically generated effective gravitational mass density of either sign. The equations of motion (EOMs) contain no free parameters and are invariant w.r.t. Milne gauge transformations. Fixing the gauge eliminates the unphysical degrees of freedom. The resulting Lagrangian possesses no free particle limit. The particles it describes, darkons, exist only as fluid particles of a self-gravitating fluid. This darkon fluid realizes the zero-mass Galilean algebra extended by dilations with dynamical exponent z = 5/3 . We reduce the EOMs to Friedmann-like equations and derive conserved quantities and a unique Hamiltonian dynamics by implementing dilation symmetry. By the Casimir of the Poisson-bracket (PB)-algebra we foliate the phase space and construct a Lagrangian in reduced phase space. We solve the Friedmann-like equations with the transition redshift and the value of the Casimir as integration constants. We obtain a deceleration phase for the early Universe and an acceleration phase for the late Universe in agreement with observations. Steady state equations in the spherically symmetric case may model a galactic halo. Numerical solutions of a nonlinear differential equation for the gravitational potential lead to predictions for the dark matter (DM) part of the rotation curves (RCs) of galaxies in qualitative agreement with observational data. We also present a general covariant generalization of the model.
Changes in Whole-Tree Water Use Following Live-Crown Pruning in Young Plantation-Grown Eucalyptus pilularis and Eucalyptus cloeziana
Authors: Alcorn Philip , Forrester David , Thomas Dane , James Ryde , Smith R. , Nicotra Adrienne , Bauhus Jürgen
Published: February 2013

Pruning of live branches is a management option to enhance wood quality in plantation trees. It may also alter whole-tree water use, but little is known about the extent and duration of changes in transpiration. In this study, sap flow sensors were used to measure transpiration for 14 days prior to, and 75 days following the removal, through pruning, of the lower 50% of the live-crown length of 10–11 m tall four-year old Eucalyptus pilularis Sm. and E. cloeziana F. Muell. trees. Pruning had no effect on stem growth, sapwood water content or radial pattern of sap velocity in either species. Pruning reduced mean daily water use by 39% in E. pilularis and 59% in E. cloeziana during the first eight days after pruning. Thirty six days after pruning there were no longer any significant differences in transpiration rates between pruned and unpruned trees in either species. Our results show that pruning of live branches had only a short-term effect on whole-tree transpiration in these sub-tropical eucalypt species.
Effects of Aging and Hypercholesterolemia on Oxidative Stress and DNA Damage in Bone Marrow Mononuclear Cells in Apolipoprotein E-deficient Mice
Authors: Tonini Clarissa , Campagnaro Bianca , Louro Lis , Pereira Thiago , Vasquez Elisardo , Meyrelles Silvana
Published: February 2013

Recent evidence from apolipoprotein E-deficient (apoE−/−) mice shows that aging and atherosclerosis are closely associated with increased oxidative stress and DNA damage in some cells and tissues. However, bone marrow cells, which are physiologically involved in tissue repair have not yet been investigated. In the present study, we evaluated the influence of aging and hypercholesterolemia on oxidative stress, DNA damage and apoptosis in bone marrow cells from young and aged apoE−/− mice compared with age-matched wild-type C57BL/6 (C57) mice, using the comet assay and flow cytometry. The production of both superoxide and hydrogen peroxide in bone marrow cells was higher in young apoE−/− mice than in age-matched C57 mice, and reactive oxygen species were increased in aged C57 and apoE−/− mice. Similar results were observed when we analyzed the DNA damage and apoptosis. Our data showed that both aging and hypercholesterolemia induce the increased production of oxidative stress and consequently DNA damage and apoptosis in bone marrow cells. This study is the first to demonstrate a functionality decrease of the bone marrow, which is a fundamental extra-arterial source of the cells involved in vascular injury repair.
Cut-and-Paste of DNA Using an Artificial Restriction DNA Cutter
Authors: Komiyama Makoto
Published: February 2013

DNA manipulations using a completely chemistry-based DNA cutter (ARCUT) have been reviewed. This cutter, recently developed by the authors, is composed of Ce(IV)/EDTA complex and two strands of pseudo-complementary peptide nucleic acid. The site-selective scission proceeds via hydrolysis of targeted phosphodiester linkages, so that the resultant scission fragments can be easily ligated with other fragments by using DNA ligase. Importantly, scission-site and site-specificity of the cutter are freely tuned in terms of the Watson–Crick rule. Thus, when one should like to manipulate DNA according to the need, he or she does not have to think about (1) whether appropriate “restriction enzyme sites” exist near the manipulation site and (2) whether the site-specificity of the restriction enzymes, if any, are sufficient to cut only the aimed position without chopping the DNA at non-targeted sites. Even the human genome can be manipulated, since ARCUT can cut the genome at only one predetermined site. Furthermore, the cutter is useful to promote homologous recombination in human cells, converting a site to desired sequence. The ARCUT-based DNA manipulation should be promising for versatile applications.
Mapping Urbanization Dynamics in Major Cities of Colombia, Ecuador, Perú, and Bolivia Using Night-Time Satellite Imagery
Authors: Parés-Ramos Isabel , Álvarez-Berríos Nora , Aide T.
Published: February 2013

By 2050, 90% of the population in Latin America will live in cities, but there is a lack of up-to-date spatial information about the urban extent and patterns of urbanization in cities of this region. In this study, we analyzed population growth, urban density and urbanization dynamics between 1992 and 2009 in the major cities of Bolivia, Colombia, Ecuador and Perú using Google Earth and DMSP/OLS night-time lights imagery. We used Google Earth to map the urban extent, and time series of night-time lights to analyze spatial patterns of urban development. The dominant urban development patterns were: high-density compact in Bogotá, Cali, Guayaquil, and Medellín; high-density expansive growth in La Paz/El Alto; low-density expansive in Quito and Santa Cruz; and a mix of high-density compact and suburban growth in Lima. Urban growth occurred largely along the periphery of cities, influenced by the local landscape and by demographic and socioeconomic factors such as immigration and housing prices. Urban density in Colombia (>20,000 per/km2) was among the highest in the world. Future growth in the region will probably be characterized by densification and slow urban expansion. This study also validates the utility of Google Earth and night-time lights for monitoring urbanization.
Antioxidant Capacity and HPLC-DAD-MS Profiling of Chilean Peumo (Cryptocarya alba) Fruits and Comparison with German Peumo (Crataegus monogyna) from Southern Chile
Authors: Simirgiotis Mario
Published: February 2013

Liquid chromatography (LC) coupled with UV detection and electrospray ionization (ESI) tandem mass spectrometry (MS/MS) was used for the generation of chemical fingerprints and the identification of phenolic compounds in peumo fruits and aerial parts from southern Chile. Thirty three compounds (19 of these detected in C. alba and 23 in C. monogyna) were identified, mainly flavonoid glycosides, phenolic acids, anthocyanins and flavonoid aglycons. Total phenolic content and total flavonoid content was measured for both species, and were higher in the extracts from C. monogyna fruits and aerial parts than extracts from C. alba. The fruits of Cryptocarya alba (Chilean peumo) presented high antioxidant capacity (9.12 ± 0.01 mg/mL in the DPPH assay), but was three times lower to that of Crataegus monogyna (German peumo) (3.61 ± 0.01 mg/mL in the DPPH assay).
GPS/GNSS Antennas. By B. Rama Rao, W. Kunysz, R. Fante and K. McDonald, Artech House, 2012; 420 Pages. Price £109.00, ISBN 978-1-59693-150-3
Authors: Lin Shu-Kun
Published: February 2013

This practical resource provides a current and comprehensive treatment of GPS/GNSS antennas, taking into account modernized systems and new and developing applications. The book presents a number of key applications, describing corresponding receiver architectures and antenna details. You find important discussions on antenna characteristics, including theory of operation, gain, bandwidth, polarization, phase center, mutual coupling effects, and integration with active components.