bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance-Based Outcomes After Nonoperative Treatment, Discectomy, and/or Fusion for a Lumbar Disc Herniation in National Hockey League Athletes
Authors: Schroeder Gregory D. , McCarthy Kathryn J. , Micev Alan J. , Terry Michael A. , Hsu Wellington K.
Published: August 2013

Background:

Ice hockey players have a high incidence of lumbar spine disorders; however, there is no evidence in the literature to guide the treatment of an ice hockey player with a herniated lumbar disc.

Purpose:

To determine the performance-based outcomes in professional National Hockey League (NHL) athletes with a lumbar disc herniation after either nonsurgical or surgical treatment.

Study Design:

Descriptive epidemiological study.

Methods:

Athletes in the NHL with a lumbar disc herniation were identified through team injury reports and archives on public record. The return-to-play rate, games played per season, points per game, and performance score for each player were determined before and after the diagnosis of a lumbar disc herniation. Statistical analysis was used to compare preinjury and postinjury performance measures for players treated with either nonsurgical or surgical treatment.

Results:

A total of 87 NHL players met the inclusion criteria; 31 underwent nonoperative care, 48 underwent a discectomy, and 8 underwent a single-level fusion. The return-to-play rate for all players was 85%. There was a significant decrease in performance in all players after a lumbar disc herniation in games played per season, points scored per game, and performance score. A comparison of the posttreatment results for the nonsurgical and surgical patient groups revealed no significant difference in performance measures. Notably, the lumbar fusion group did not show a decrease in games played per season or performance score after surgery, likely secondary to a small sample size.

Conclusion:

National Hockey League players with a lumbar disc herniation have a high return-to-play rate regardless of the type of treatment; however, performance-based outcomes may decrease compared with preinjury levels. The study data suggest that a lumbar fusion is compatible with a return to play in the NHL, which is in contrast to other professional sports.
An Examination of the Validity of the Dynamic Indicators of Vocabulary Skills (DIVS)
Authors: Marcotte Amanda M. , Parker Christopher , Furey William , Hands Jessica L.
Published: August 2013

There is empirical evidence to suggest that oral language and vocabulary on entering kindergarten are the best predictors of later reading success. Identifying skills that are predictive of later achievement using psychometrically sound measurement methods is a necessary component of early intervention efforts. Currently, there are limited methods for measuring early vocabulary acquisition. The Dynamic Indicators of Vocabulary Skills (DIVS) were designed to measure the vocabulary of preschool and kindergarten students. The purpose of this article is to contribute to the psychometric evidence supporting the use of the DIVS as effective measures of early vocabulary acquisition. This article presents an array of validity evidence for the DIVS, including predictive validity and the construct validity evaluated by both convergent validity and discriminant validity estimates.
Emotional and Behavioral Screener
Authors: Nordness Philip D. , Epstein Michael H. , Cullinan Douglas , Pierce Corey D.
Published: August 2013

The Emotional and Behavioral Screener (EBS) is a universal screening instrument designed to identify students whose excessive problem behaviors put them at risk of the education disability category of emotional disturbance (ED). This article reports findings from three studies that address the reliability and validity of the EBS. Studies 1 and 2 examined the test–retest and inter-rater reliability of the EBS. Study 3 investigated the convergent validity of the EBS by comparing it to the Behavioral and Emotional Screening System. The results from these studies support the reliability and validity of the EBS as a universal screening instrument for identifying students who may be at risk of ED or those who may require a greater degree of monitoring, decision-making, formal assessment, or intervention to restore normal behavior functioning and prevent identification as ED. Implications, research limitations, and future research needs are discussed.
Influence of Body Mass Index, Perceived Media Pressure, and Peer Criticism/Teasing on Adolescent Girls’ Body Satisfaction/Dissatisfaction and Clothing-Related Behaviors
Authors: Seock Yoo-Kyoung , Merritt Leslie Rene
Published: August 2013

The present study investigated the relative importance of Body Mass Index (BMI), perceived media pressure, and peer criticism/teasing for body satisfaction/dissatisfaction of female adolescents and their clothing-related behaviors. This study also examined the influence of body satisfaction/dissatisfaction on clothing-related behaviors. Data were collected from a convenience sample of 320 high school girls living in a southeastern part of the United States. The data analysis consisted of exploratory factor analysis, hierarchical regression analysis, and bivariate and multiple regression analyses. When examining the relative importance of the three variables on adolescent girls' body satisfaction, BMI was found to be the least important factor. When entered into the regression equation alone, BMI was found to be a significant determinant of body satisfaction/dissatisfaction. However, when it was entered into the regression equation with perceived media pressure and peer criticism/teasing, BMI was not a significant factor. The results showed that perceived media pressure and peer criticism/teasing have significant negative influences on adolescent girls' body satisfaction. The results further indicated that perceived pressure from media affects both self-enhancing and body-concealing clothing-related behaviors. The results also revealed that peer criticism/teasing is a critical determinant of Body-Concealing Behavior. BMI, however, do not demonstrate significant influence on either self-enhancing or body-concealing behaviors. A significant positive relationship was found between body satisfaction and self-enhancing behaviors, whereas a significant negative relationship was found between body satisfaction and body-concealing behaviors.
Modeling and calibration of pointing errors using a semi-parametric regression method with applications in inertially stabilized platforms
Authors: Hong Huajie , Zhou Xiaoyao , Zhang Zhiyong , Fan Dapeng
Published: August 2013

This article investigates modeling and calibration issues that are associated with inertially stabilized platforms to achieve accurate pointing. In modeling part, the Denavit–Hartenberg notation is used to perform an error analysis of the kinematics of inertially stabilized platforms. A physical model is then established to illustrate the effects of geometric errors that are caused by imprecision in the manufacturing and assembly processes on the pointing accuracy of inertially stabilized platforms. In the calibration part, an improved hybrid model denoted as the semi-parametric regression model is developed to compensate for remaining nonlinear errors. With applications to a two-degree-of-freedom miniature inertially stabilized platform, semi-parametric regression model is shown to outperform physical model substantially in all cases. The experimental results also indicate that the proposed semi-parametric regression model eliminates both the geometric and nonlinear errors, and that the pointing accuracy of miniature inertially stabilized platform significantly improves after compensation.
A study on material flow pattern in friction stir welding using finite element method
Authors: Pashazadeh Hamed , Masoumi Abolfazl , Teimournezhad Jamal
Published: August 2013

In this article, numerical modelling of friction stir welding of copper plates is presented. The aim of this study is to implement DEFORM-3D for developing the numerical simulation. Material flow patterns are extracted using point tracking method, and mechanical/metallurgical properties of workpiece are analysed. Simulation results suggest that material particles in front of the tool pin tend to pass and settle behind the pin from the retreating side. Based on the results, a new classification of distinctive zones in the stirred zone is presented. The stir zone shape in friction stir welding is divided into five distinctive zones. In friction stir welding of copper metals, the stir zone does not lean completely towards any sides of the welding line, which was found to compare favourably with experimental observations.
Evaluation of primary phase morphology of cooling slope cast Al-Si-Mg alloy samples using image texture analysis
Authors: Das Prosenjit , Dutta Samik , Samanta Sudip K
Published: August 2013

Rheopressure die casting is one of the newest casting processes of present era for manufacturing of near-net-shaped cast components with improved mechanical properties and high-dimensional accuracy. Rheopressure die casting demands especially prepared semi-solid alloy slurry having nearly globular primary Al phase. In this study, a cooling slope has been employed to produce semi-solid slurry of Al-Si-Mg (A356) alloy and successively cast in a metallic mould. Image texture analysis techniques have been implemented for accurate evaluation of the primary phase morphology of cast samples. In this research, efforts have been made to apply fractal analysis and run-length statistical analysis techniques for automatic characterization of optical micrographs of cast samples produced at different processing conditions.
Modeling of silicon ingot slicing process by wire–electrical discharge machining
Authors: Dongre Ganesh G , Vesivkar Cyrus , Singh Ramesh , Joshi Suhas S
Published: August 2013

Photovoltaic industry requires the cutting of silicon ingots into wafers in order to get minimum kerf loss, to facilitate manufacturing of thin wafers and to provide high productivity. Existing silicon ingot slicing processes like inner diameter saw and abrasive wire cutting have drawbacks of high kerf loss, lower finish and limitation on the thickness of wafer. In order to have economically viable photovoltaic technology, efficiency of wafer manufacturing process needs to be improved. The wire–electrical discharge machining technology is adopted as a new candidate for silicon slicing and is compared with the existing procedures and testified whether it can inevitably substitute the inner diameter saw or even compete with wire saws in some manufacturing orders. The main focus of this article is to understand the effect of processing parameters on the cutting process, so the parametric conditions delivering high slicing rate and low kerf loss can be achieved. Modeling of wire–electrical discharge machining is difficult as it involves several disciplines such as thermodynamics, hydrodynamics, electrodynamics and electromagnetics. Various researchers have proposed analytical models for electrical discharge machining and wire–electrical discharge machining through the use of electrothermal concepts. However, a comprehensive model that predicts the erosion rate in wire–electrical discharge machining process is needed. This article considers moving the line heat source nature of the wire to predict the temperature profiles of the workpiece in order to calculate the erosion rate. The results thus obtained have been analyzed experimentally, and conclusions have been derived enabling a better understanding of future research prospects and applications.
An industrially feasible approach to process optimisation of abrasive flow machining and its implementation perspectives
Authors: Howard Mitchell , Cheng Kai
Published: August 2013

This article presents a novel industrially feasible approach to ensure that an integrated optimum configuration of machine, media and geometry is achieved for abrasive flow machining process optimisation. Historically, new part introduction requires a trial-and-error phase to develop a process model, while the proposed method identifies two key explanatory variables (edge form and average roughness) and the process conditions in which they are achieved in testpiece geometry. The method and its shop-floor implementation perspectives are evaluated and verified through computational fluid dynamics simulation and well-designed machining trials, plus reapplied to more complex workpieces. The method can significantly improve abrasive flow machining process capability, accuracy and efficiency and be used to optimise machine design, attempt radical new methods of workpiece fixturing and provide an avenue to incorporate and reanalyse the adaptations of abrasive flow machining machinery.
Investigation of the effect of different cutting parameters on chip formation of low-lead brass with experiments and simulations
Authors: Laakso Sampsa VA , Hokka Mikko , Niemi Esko , Kuokkala Veli-Tapani
Published: August 2013

Poor chip breakage causes problems in machining of low-lead brass. To improve chip breakage, finite element model simulations were implemented in cutting tool design. Finite element model simulations enable high number of experiments that would be expensive and slow to perform by conventional cutting tests. Compression tests and cutting experiments under different temperatures and strain rates were performed for lead-free brass, to acquire material parameters for the finite element model. It was observed that the coupled effect of thermal softening and rate sensitivity of the material was difficult to take into account with the existing material model. Furthermore, it was found that there are no reported material models that can take rate sensitivity–temperature coupling into account. This was counteracted by fitting the model with least square method to the stress–strain data at the cutting temperature, although this causes error in simulations with temperatures higher or lower than the supposed cutting temperature. Nevertheless, the simulated results proved accurate enough to model the chip breakage. Based on the simulations and experiments, the use of a positive rake angle, high cutting speed and low cutting feed rate improve chip breakage from continuous chip to a chip of average length of 4 mm.
Energy-aware resource service scheduling based on utility evaluation in cloud manufacturing system
Authors: Cheng Ying , Tao Fei , Liu Yilong , Zhao Dongming , Zhang Lin , Xu Lida
Published: August 2013

In order to realize the manufacturing resource sharing and optimal allocation, many advanced manufacturing modes and technologies have been proposed and researched, but few works have been emphasized on resource service and capability transaction and scheduling management. With these conditions, in this article, the concept of cloud manufacturing mode is first briefly introduced, and a general cloud manufacturing resource service scheduling model is established. Then, the comprehensive utility models, which consider energy consumption, cost, and risk for the three sides (i.e. provider, consumer, and operator), are established in the resource service scheduling process in cloud manufacturing system. Four kinds of resource service scheduling modes, which are provider centered, consumer centered, operator centered, and system centered, are studied. These modes are based on the utility models that are investigated, as well as the system-centered cooperative scheduling method that is designed with risk-sharing strategy. The experimental results show that the system-centered scheduling method has the highest potential for realizing the aim of cloud manufacturing, and the system-centered cooperative scheduling method is rational to obtain the higher maximal utilities of the whole system and the three key users at the same time. It promotes the higher efficiency and utility, a higher rate of sharing, green and on-demand use of decentralized manufacturing resources and capability services in cloud manufacturing systems.
Random or intuitive nozzle position in high-speed milling using minimum quantity lubricant
Authors: Mulyadi Ismet H , Mativenga Paul T
Published: August 2013

High-speed machining, the need to reduce environmental impact and manufacturing cycle time have promoted the use of minimum quantity lubricant in mechanical machining. However, in minimum quantity lubricant, where a small quantity of cooling lubricant is delivered to the cutting zone, the sensitivity of machining performance to nozzle position has hardly been explored in research or noted in industrial practice. In this study of conventional versus high-speed machining, the focus was on a systematic study of the effect of nozzle position on tool wear. This study elucidates the effect of spindle rotation speed on the sensitivity of nozzle location in order to enhance machining performance. This work provides some fundamental information regarding the position and orientation of the nozzle in order to maximise the benefits of machining using minimum quantity lubricants. This work is of significant importance for the repeatability of minimum quantity lubricant machining operations and to promote longer tool life in particular for machine shops where nozzles are currently randomly oriented to the cutting zone.
Effect of welding parameters on bead profile, microhardness and H2 content in submerged arc welding of high-strength low-alloy steel
Authors: Jindal Sandeep , Chhibber Rahul , Mehta Narinder P
Published: August 2013

In oil and gas industries, submerged arc welding is the only primarily used process to weld high thickness, large distance structural oil pipes. Welding process parameters play a significant role in determining the quality of a weld joint in submerged arc welding. In the present work, an attempt has been made to optimize the weld bead parameters: weld bead form factor, dilution, microhardness and diffusible hydrogen content for welding of structural pipe steel (API 5L X65 grade) by desirability function approach used by Derringer and Harrington. For design of experiments, response surface methodology had been used. Mathematical models for output responses had been developed in terms of welding parameters and checked for adequacy using t-test and analysis of variance (F-test). It was found that welding current was the most significant parameter controlling all the responses, and arc voltage had increasing effect on all the responses except microhardness.
Research on the machined surface integrity under combination of various inclination angles in multi-axis ball end milling
Authors: Chen Xiaoxiao , Zhao Jun , Dong Yongwang , Li Anhai , Wang Dong
Published: August 2013

It is well known that the multi-axis machining technology has been developed into a key technique applied in the manufacturing field. The machined surface integrity is one of the most important factors influencing the performance of the produced components. Hence, this research concentrated on the machined surface integrity induced by the multi-axis milling operation with different inclination angle combinations. In this research work, the cutting conditions of the conventional or up-milling process with tool orientations were divided into eight different types, and the machining characteristics corresponding to different cutting strategies were discussed. The varying conditions of surface topography, texture and other machining features induced in machining process which corresponds to different inclination angle combinations were analyzed by geometrical analysis, and the surface roughness and linear profile along specific directions on the machined surface were also investigated. There is a special corresponding relationship between the rotation angle and tool tilt and lead angles. Better surface roughness could be achieved when rotation angles are 0° (positive lead), 60° (combination of positive tilt and positive lead), 90° (positive tilt) and 330° (combination of negative tilt and positive lead). Then, the samples used for study of the metamorphic layer were produced by lapping and polishing process, and the macro hardness (HL) and micro-hardness (HV) of the top machined surface were investigated. According to the measured results of both Leeb hardness and micro-hardness, higher surface hardness could be obtained under rotation angles of 60° (combination of positive tilt and positive lead), 120° (combination of positive tilt and negative lead) and 210° (negative tilt and negative lead). Moreover, the variations of the micro-hardness along the depth direction of the samples were studied. Finally, discussions on the machined surface residual stresses in both feed and cross-feed direction were carried out. Compressive surface residual stress in both feed and cross-feed direction could be generated when rotation angles are 210° (combination of negative tilt angle with smaller value and negative lead angle with larger value) and 330° (combination of negative tilt angle with smaller value and positive lead angle with larger value). Generally, the evaluation indicators of surface integrity are not all very satisfying under one special cutting condition with a certain inclination angle combination, and the optimal cutting parameters should be selected based on the specific application requirements. Finally, the optimal tool orientations and related cutting parameters were recommended, and further studies of the related topics were also presented.
Hydrostatic spindle dynamic design system and its verification
Authors: Chen Wanqun , Sun Yazhou , Liang Yingchun , Bai Qingshun , Zhang Peng , Liu Haitao
Published: August 2013

A design system for hydrostatic spindle is presented in light of the dynamic synthesis, which is based on the laws of the fluid mechanics, engineering thermodynamics and rotor dynamics. The finite element theory and hydrostatic principle are integrated into the design process, which provides not only the analyses and determination of the stiffness and temperature rise of the hydrostatic bearing but also the dynamic performance optimization. The proposed design system was implemented through a hydrostatic spindle on ultra-precision machining tools with the flycutting process.
Fabrication of cylindrical micro tools by micro electrochemical form turning operation
Authors: Das Alok K , Saha Partha
Published: August 2013

Cylindrical micro tools of tungsten material have various applications in micro devices and systems because of its high rigidity and toughness. This article deals with the fabrication of cylindrical micro tools from tungsten rod by micro electrochemical form turning operation using KOH solution as electrolyte. The experiments were conducted with an indigenously developed setup with the variation of different experimental parameters to get good cylindrical shape of the tool. Cylindrical micro tools of diameter less than 50 µm and length of up to 1 mm have been fabricated through this process from tungsten rods of initial diameter of 1.5 mm within the time duration of 15 min. This process produces cylindrical micro tools from a much larger initial diameter of tungsten rod and with low lead time, as compared to the reported literatures. The variation of the cylindrical length of the micro tool according to the variation of parameters such as pulse on time, applied voltage and concentration of electrolyte has been analyzed, and the optimum parameter settings for getting the better shape and surface finish of the cylindrical electrode are electrode gap distance of 100 µm, frequency of the pulse power supply of 500 kHz, voltage of 18 V, electrolyte concentration of 3 M and pulse on time of 1400 ns.
An investigation on machinability assessment of difficult-to-cut materials based on radar charts
Authors: Wan Yi , Cheng Kai , Liu Zhanqiang , Ye Hongtao
Published: August 2013

A scientific understanding of all the factors affecting machinability and machining is essential for tool selection and process planning, particularly in Computer Numerical Control (CNC) machining of difficult-to-cut materials. This article proposed a radar chart–based method to assess material machinability by taking into account of multiple process variables quantitatively and to reveal comparison indexes visually. Key steps of this method included the reference material and indexes selection, normalization process and machinability assessment. Finally, a case study on using this method was given to assess three different types of titanium alloys. The order of machinability from good to poor is TC4, TC11 and TC17 supported with quantitative analysis.
The Relative Trustworthiness of Inferential Tests of the Indirect Effect in Statistical Mediation Analysis
Authors: Hayes Andrew F. , Scharkow Michael
Published: August 2013

A content analysis of 2 years of Psychological Science articles reveals inconsistencies in how researchers make inferences about indirect effects when conducting a statistical mediation analysis. In this study, we examined the frequency with which popularly used tests disagree, whether the method an investigator uses makes a difference in the conclusion he or she will reach, and whether there is a most trustworthy test that can be recommended to balance practical and performance considerations. We found that tests agree much more frequently than they disagree, but disagreements are more common when an indirect effect exists than when it does not. We recommend the bias-corrected bootstrap confidence interval as the most trustworthy test if power is of utmost concern, although it can be slightly liberal in some circumstances. Investigators concerned about Type I errors should choose the Monte Carlo confidence interval or the distribution-of-the-product approach, which rarely disagree. The percentile bootstrap confidence interval is a good compromise test.
From Glue to Gasoline
Authors: Pierce Jason R. , Kilduff Gavin J. , Galinsky Adam D. , Sivanathan Niro
Published: August 2013

Perspective taking is often the glue that binds people together. However, we propose that in competitive contexts, perspective taking is akin to adding gasoline to a fire: It inflames already-aroused competitive impulses and leads people to protect themselves from the potentially insidious actions of their competitors. Overall, we suggest that perspective taking functions as a relational amplifier. In cooperative contexts, it creates the foundation for prosocial impulses, but in competitive contexts, it triggers hypercompetition, leading people to prophylactically engage in unethical behavior to prevent themselves from being exploited. The experiments reported here establish that perspective taking interacts with the relational context—cooperative or competitive—to predict unethical behavior, from using insidious negotiation tactics to materially deceiving one’s partner to cheating on an anagram task. In the context of competition, perspective taking can pervert the age-old axiom “do unto others as you would have them do unto you” into “do unto others as you think they will try to do unto you.”
Giving Preschoolers Choice Increases Sharing Behavior
Authors: Chernyak Nadia , Kushnir Tamar
Published: August 2013

Young children are remarkably prosocial, but the mechanisms driving their prosociality are not well understood. Here, we propose that the experience of choice is critically tied to the expression of young children’s altruistic behavior. Three- and 4-year-olds were asked to allocate resources to an individual in need by making a costly choice (allocating a resource they could have kept for themselves), a noncostly choice (allocating a resource that would otherwise be thrown away), or no choice (following instructions to allocate the resource). We measured subsequent prosociality by allowing children to then allocate new resources to a new individual. Although the majority of children shared with the first individual, children who were given costly alternatives shared more with the new individual. Results are discussed in terms of a prosocial-construal hypothesis, which suggests that children rationally infer their prosociality through the process of making difficult, autonomous choices.
The Reappropriation of Stigmatizing Labels
Authors: Galinsky Adam D. , Wang Cynthia S. , Whitson Jennifer A. , Anicich Eric M. , Hugenberg Kurt , Bodenhausen Galen V.
Published: August 2013

We present a theoretical model of reappropriation—taking possession of a slur previously used exclusively by dominant groups to reinforce another group’s lesser status. Ten experiments tested this model and established a reciprocal relationship between power and self-labeling with a derogatory group term. We first investigated precursors to self-labeling: Group, but not individual, power increased participants’ willingness to label themselves with a derogatory term for their group. We then examined the consequences of such self-labeling for both the self and observers. Self-labelers felt more powerful after self-labeling, and observers perceived them and their group as more powerful. Finally, these labels were evaluated less negatively after self-labeling, and this attenuation of stigma was mediated by perceived power. These effects occurred only for derogatory terms (e.g., queer, bitch), and not for descriptive (e.g., woman) or majority-group (e.g., straight) labels. These results suggest that self-labeling with a derogatory label can weaken the label’s stigmatizing force.
Postglacial spatiotemporal peatland initiation and lateral expansion dynamics in North America and northern Europe
Authors: Ruppel Meri , Väliranta Minna , Virtanen Tarmo , Korhola Atte
Published: August 2013

Peatlands are major ecosystems of the Northern Hemisphere and have a significant role in global biogeochemical processes. Consequently, there is growing interest in understanding past, present and future peatland dynamics. However, chronological and geographical data on peatland initiation are scattered, impeding the reliable establishment of postglacial spatiotemporal peatland formation patterns and their possible connection to climate. In order to present a comprehensive account of postglacial peatland formation histories in North America and northern Europe, we collected a data set of 1400 basal peat ages accompanied by below-peat sediment-type interpretations from literature. Our data indicate that all peatland initiation processes (i.e. primary mire formation, terrestrialization and paludification) co-occurred throughout North America and northern Europe during the Holocene, and almost equal amounts of peatlands formed via these three processes. Furthermore, the data suggest that the processes exhibited some spatiotemporal patterns. On both continents, primary mire formation seems to occur first, soon followed by terrestrialization and later paludification. Primary mire formation appears mostly restricted to coastal areas, whereas terrestrialization and paludification were more evenly distributed across the continents. Primary mire formation seems mainly connected with physical processes, such as ice sheet retreat. Terrestrialization probably reflected progressive infilling of water bodies on longer timescales but was presumably drought driven on shorter timescales. Paludification seems affected by climate as it slowed down in Europe during the driest phase of the Holocene between 6 and 5 ka. Lateral expansion of existing peatlands accelerated c. 5000 years ago on both continents, which was likely connected to an increase in relative moisture.
Human–landscape interactions in the Bologna area (northern Italy) during the mid–late Holocene, with focus on the Roman period
Authors: Bruno Luigi , Amorosi Alessandro , Curina Renata , Severi Paolo , Bitelli Remo
Published: August 2013

Integrated sedimentological and archaeological investigations of mid–late Holocene deposits from the subsurface of Bologna elucidate the complex relationship among urban settlement, human society, geomorphology and climate change at the southern margin of the Po Plain. Above the Pleistocene–Holocene unconformity, the Holocene succession forms an intricate mosaic of alluvial deposits. Two palaeosols, spanning between about 8000–5000 cal. yr BP and 3200–1500 cal. yr BP, respectively, represent the most prominent stratigraphic markers across the study units. A huge amount of archaeological remains from the younger palaeosol enables the identification of an uninterrupted sequence of settlements from the Early Iron Age to the Late Roman period. The first permanent settlements of Iron Age took place in a topographically elevated region protected from flooding. The onset of paedogenesis during this period reflects the radical transformation of the environment by human settlements through widespread control of the river network and setting of regular patterns of irrigation channels. A period of exceptional climate stability characterized the expansion of the Roman Empire. This phase is testified by a wealth of exceptionally preserved archaeological material, including buildings, cemetery sites, streets and irrigation channels. Subsurface correlations of the Roman palaeosol enable detailed reconstruction of the Roman topography, with special focus on fluvial paths and communication routes. The decline of the Roman Empire, hit by a devastating epidemic and the barbarian invasions, was paralleled by a phase of climatic deterioration, resulting in the abandonment of rural lands and degradation of the river network, which ultimately favoured the burial of Roman settlement.
Late Weichselian and Holocene sedimentary palaeoenvironment and glacial activity in the high-arctic van Keulenfjorden, Spitsbergen
Authors: Kempf Philipp , Forwick Matthias , Laberg Jan Sverre , Vorren Tore O
Published: August 2013

High-arctic fjords, for example, van Keulenfjorden on Spitsbergen, provide valuable palaeoenvironmental archives as they typically contain landforms and sediment sequences that document past changes in glacial activity with high temporal resolution. Van Keulenfjorden was covered with a grounded glacier during the last glacial, and it was deglaciated between c. 11.8 and 11.3 cal. ka BP. The retreat of the ice front accelerated from approximately 80 to 190 m/a during the deglaciation. The maximum late Holocene glacier extent occurred after surge-like advances of the glacier Nathorstbreen between 2790 and 2610 cal. yr BP (i.e. during a period with the coldest climatic conditions on Svalbard). This maximum extent was reached approximately 2600 years earlier than inferred for most fjords on Svalbard, suggesting that surge-like glacier advances on Svalbard can occur under variable climatic conditions. The time interval between the advances of Nathorstbreen around 2.7 ka BP was approximately 100–150 years. This is comparable to the last and only historically known quiescent phase of Nathorstbreen of c. 120 years between the late 19th century and the most recent surge from 2003 to 2012.
The relationship between environmental exposure to cadmium and lead and blood selenium concentration in randomly selected population of children inhabiting industrial regions of Silesian Voivodship (Poland)
Authors: Gać P , Pawlas N , Poręba R , Poręba M , Pawlas K
Published: August 2013

This study aimed at determining the relationship between environmental exposure to lead (Pb) and cadmium (Cd) and blood selenium (Se) concentration in randomly selected population of children inhabiting the industrial regions of Silesian Voivodship, Poland. The study was conducted on a group of consecutive randomly selected 349 children aged below 15 years and inhabiting the industrial regions in Upper Silesia. The examined variables included whole blood Cd concentration (Cd-B), whole blood Pb concentration (Pb-B) and whole blood Se concentration (Se-B). The concentration of Cd-B, Pb-B and Se-B in the studied group of children amounted to 0.26 ± 0.14, 37.62 ± 25.30 and 78.31 ± 12.82 μg/L, respectively. In the entire examined group a statistically significant negative linear relationship was noted between Pb-B and Se-B ( r = −0.12, p < 0.05). Also, a statistically insignificant negative correlation was detected between Cd-B and Se-B ( r = −0.02, p > 0.05) and a statistically insignificant positive correlation between Pb-B and Cd-B ( r = 0.08, p > 0.05). A multivariate backward stepwise regression analysis demonstrated that in the studied group of children higher Pb-B and a more advanced age-represented independent risk factors for a decreased Se-B. Environmental exposure to Pb may represent an independent risk factor for Se deficit in blood of the studied population of children. In children, the lowered Se-B may create one of the mechanisms in which Pb unfavourably affects human body.
The Development of Prosocial Behavior in Adolescents
Authors: Furman Nate , Sibthorp Jim
Published: August 2013

Learning transfer and prosocial behavior (PSB) are critical components of many outdoor education programs for adolescents. This study examined the effects of a theoretically grounded treatment curriculum designed to foster the transfer of learning of general and contextual PSB (also called expedition behavior) among adolescents enrolled on 14-day backpacking courses with the National Outdoor Leadership School. Results suggest that the treatment curriculum increased proximal learning of PSB more than courses that featured the traditional curriculum. Qualitative results suggested that students learned PSB primarily as a result of its relevance to the expedition environment, that it is most useful when working with or understanding others, and that it can be applied to multiple contexts post-course, including with family, at school, and with sport teams. Implications for designing a curriculum that fosters transfer and for developing PSB in participants are considered.
Adventure Education and the Acculturation of First-Generation Chinese Canadians in Vancouver, Canada
Authors: Lo Simon , Gidlow Bob , Cushman Grant
Published: August 2013

This article reports on research that demonstrates how parents in first-generation Chinese families in Vancouver, Canada, most of them from Hong Kong, control their children’s involvement in local adventure education (AE) programs and in so doing minimize the likelihood of intergenerational culture conflict involving those children. The research is based on 28 face-to-face, digitally recorded interviews with 14- to 18-year-old participants, their parents, and instructors, in two AE programs in Vancouver, Canada. The interviews were conducted in 2009.
A Socio-environmental Case for Skill in Outdoor Adventure
Authors: Mullins Philip M.
Published: August 2013

In response to the crisis of sustainability, this paper revisits understandings of human–environment relations established through skill-based outdoor activities that are used commonly among adventure recreation, education, and tourism. Reconsidering a predominant focus on risk and a persistent tension between technical and environmental knowledge, a case is made for skill as an important avenue for research related to participants’ environmental learning and engagement. Diverse qualitative and quantitative research literature concerning outdoor education, recreation specialization, place, and skilled performance are reviewed. The author argues that developing theoretical and practical approaches to outdoor adventure education, recreation, and tourism within a sustainability paradigm will require perspectives that position humanity as belonging within environments, and that skill provides an important avenue for doing so. Ultimately, research and practice will need to account for skill development and performance as shaping—for better or worse—participants’ socioecological engagement.
Conceptualizing Skill Within a Participatory Ecological Approach to Outdoor Adventure
Authors: Mullins Philip M.
Published: August 2013

To answer calls for an ecological approach to outdoor adventure that can respond to the crisis of sustainability, this paper suggests greater theoretical and empirical attention to skill and skill development as shaping participant interactions with and experiences of environments, landscapes, places, and inhabitants. The paper reviews calls for ecological approaches as well as phenomenological analyses of outdoor adventure. The paper then outlines a heuristic perspective that positions humanity as belonging within environments and highlights the performative and movement orientation of outdoor adventure. Ingold’s work is outlined as an informative ecological ontology and, integrating it with the literature reviewed, alternative conceptualizations of skill, activity, and outdoor adventure are provided. These understandings enable a first step in formulating and researching a participatory ecological approach to outdoor adventure education, recreation, and tourism.
Investigating the Impact of Field Trips on Teachers’ Mathematical Problem Posing
Authors: Courtney Scott A. , Caniglia Joanne , Singh Rashmi
Published: August 2013

This study examines the impact of field trip experiences on teachers’ mathematical problem posing. Teachers from a large urban public school system in the Midwest participated in a professional development program that incorporated experiential learning with mathematical problem formulation experiences. During 2 weeks of summer 2011, 68 teachers from eight low-achieving city schools explored city landmarks that were not only accessible to the general public but were also considered rich in mathematical connections. Field trips included museums, historical landmarks, a local airport, and an international sporting event. Following each field trip, teachers were asked to create inquiry-based mathematics problems grounded in these experiences to implement in their classrooms. This article discusses the impact field trips and accompanying professional development activities had on teachers’ ability to create problems that provide students with opportunities to engage in meaningful mathematics.
Effects of a Developmental Adventure on the Self-Esteem of College Students
Authors: Paquette Linda , Brassard Audrey , Guérin Audrey , Fortin-Chevalier Justine , Tanguay-Beaudoin Laurence
Published: August 2013

This study examines the effects of outdoor developmental adventure programming (ODA) on college students’ self-esteem. Although some previous studies have shown that outdoor adventure programming has positive effects on self-esteem, others did not find any effect. A quasi-experimental study was conducted over 5 months, which included two pretests and two posttests to address some limitations of previous studies. A total of 84 participants completed the Questionnaire d’estime de soi hiérarchique, a questionnaire assessing self-esteem on four occasions. The experimental group (outdoor adventure; n = 32) was compared with the control groups (travel, n = 17; soccer, n = 35) using repeated measures of covariance analyses. Positive and significant increases were found for the athletic dimension of self-esteem and for global self-esteem for the experimental group (outdoor adventure) only. The increased benefits provided by the combination of adventure and sports in ODA, over sports-only or traveling-only interventions, underline the importance of developing ODA with college students.
Nonlinear feedback controller of a microbeam resonator
Authors: Ouakad Hassen M , Nayfeh Ali H , Choura Slim , Najar Fehmi
Published: August 2013

This paper is concerned with the modeling, nonlinear dynamic analysis and control design of an electrostatically actuated clamped-clamped microbeam. The model accounts for the mid-plane stretching and nonlinear form of the electrostatic force actuated along the microbeam span. A reduced-order model is constructed, using the method of multiple scales, to examine the microsystem static and dynamics behaviors. To improve the microbeam behavior, a nonlinear feedback controller is proposed. The main control objective is to make it behave like commonly known one-degree-of-freedom self-excited oscillators, such as the van der Pol and Rayleigh oscillators, which depict attractive filtering features in their dynamic frequency responses. For this, a review of the nonlinear dynamics of one of these oscillators is first provided to gain insight into its appealing filtering characteristics. We then present a novel control design that regulates the pass band of the considered microbeam and derive analytical expressions that approximate the nonlinear resonance frequencies and amplitudes of the periodic solutions when it is subjected to one-point then to fully distributed feedback forces. We apply Floquet theory to ascertain the stability of the limit cycles. We finally suggest an electronic circuitry made of six analog devices AD633JN for the implementation of the proposed feedback controller.
Expanding Resource Theory and Feminist-Informed Theory to Explain Intimate Partner Violence Perpetration by Court-Ordered Men
Authors: Basile Kathleen C. , Hall Jeffrey E. , Walters Mikel L.
Published: August 2013

This study tested resource and feminist-informed theories to explain physical, sexual, psychological, and stalking intimate partner violence (IPV) perpetrated by court-mandated men. Data were obtained from 340 men arrested for physical assault of a partner before their court-ordered treatment. Using path analysis, findings provided partial support for each model. Ineffective arguing and substance-use problems were moderators of resources and perpetration. Dominance mediated early exposures and perpetration in the feminist-informed model. In both models, predictors of stalking were different than those for other types of perpetration. Future studies should replicate this research and determine the utility of combining models.
Changed and Changing Gender and Family Roles and Domestic Violence in African Refugee Background Communities Post-Settlement in Perth, Australia
Authors: Fisher Colleen
Published: August 2013

In this study, domestic violence (DV) in five African refugee background communities post-settlement in Perth, Australia, is investigated—specifically, the interrelationship between experiences of DV, and changed and changing gender and family roles and responsibilities. The participatory qualitative design utilized in-depth interviews with 54 members of the Somalian, Sierra Leonean, Ethiopian, Liberian and Sudanese Communities, and focus groups with 24 professionals who support them. Three key dimensions of this interrelationship are discussed: “male loss of the breadwinner role and status,” “financial independence,” and “mismatch between formal response and expectations.” The importance of understanding experiences of DV within the context of cultural transition is highlighted here.
Violence Against Women and HIV Risk Behaviors in Kampala, Uganda
Authors: Francisco Leilani , Abramsky Tanya , Kiss Ligia , Michau Lori , Musuya Tina , Kerrigan Deanna , Kaye Dan , Watts Charlotte
Published: August 2013

This article presents baseline data from the SASA! (this is the Swahili for ‘now’) Study, a cluster randomized trial of a community-mobilization intervention to prevent violence against women and HIV/AIDS in Kampala, Uganda. Logistic regression was used to explore associations between intimate partner violence (IPV) and sexual risk behaviors, among 1,206 ever-partnered men and women (18-49 years). Twenty-seven percent of women reported past-year experience of physical and/or sexual IPV. Female experience and male perpetration of IPV were strongly associated with sexual risk behaviors. Findings confirm the importance of the SASA! intervention in this setting and endorse integrated strategies for IPV and HIV prevention.
Partner Violence and Substance Abuse Are Intertwined
Authors: Macy Rebecca J. , Renz Connie , Pelino Emily
Published: August 2013

Research shows that co-occurring partner violence and substance abuse are problems for many women. However, less is known about women’s varied experiences with partner violence and substance abuse. This exploratory, qualitative study investigates these two issues among a sample of 15 women in substance abuse treatment who experienced partner violence. Overall, findings show participants’ experience of violence–substance connections varied in important ways; complicating factors exacerbate both problems; and domestic violence services and substance abuse treatments should account for these variations and complications. We discuss directions for providers, researchers, and policymakers concerned with partner violence or substance abuse.