Type Of Proximity Research Articles

Dynamics Analysis of Separation Mechanism for Rotating Projectiles at the End of Trajectory

Spin separation technology is a key technology for realizing the detection function at the end of the rotational trajectory. It is also a necessary condition for the fuse control system to adjust its control strategy according to actual combat needs. To explore a new type of proximity fuse detection method, this article first designs a detection separation mechanism for the end of the trajectory. An interior ballistic model of the separation mechanism was then established through closed bomb tests and equivalent interior ballistic equations, and the aerodynamic parameters of the front-stage separation body at the moment of separation were obtained based on computational fluid dynamics numerical simulation. Finally, a separation dynamics model of the separation mechanism was established to analyze the motion state after the separation action of the front-stage separation body. The results demonstrate the feasibility of the proposed separation mechanism. The discrepancy between the simulation and experiment of the velocity increment for the front-stage separation body is about 1.07%. The attack angle for the front-stage separation body is below 2°, and the period with a displacement between two stage bodies greater than 3 m is around 0.365 s. This research can provide new ideas and theoretical references for the design of a similar fuse detection separation mechanism.

Multi-criterion analysis of the effect of physico-chemical microbiological agents on Legionella detection in hotel water distribution systems in Crete.

Water distribution systems in hotels have been related to outbreaks caused by Legionella spp. Certain measures, including disinfection by chlorination, maintaining increased temperatures are usually undertaken to prevent Legionella outbreaks. However, these preventive strategies are not always effective, since there are several factors (e.g., synergistic interactions with other microbes, physico-chemical factors, biofilm formation, availability of nutrients) that promote survival and proliferation of the pathogen in water pipes., Accordingly, there is a need of a holistic approach in development of preventive models for Legionella outbreaks associated with water distribution systems. Water samples were collected from hotel water systems and were tested for the presence of Legionella, E. coli, total coliforms, total mesophilic count and Pseudomonas. In each sample, temperature and chlorine were also tested. Other epidemiological factors were additionally recorded including number of rooms, stars, proximity of sampling point to the boiler, etc. Data were processed by generalized linear analysis, and modeling based on logistic regression analysis to identify independent predictive factors associated with the presence of Legionella in hotel water systems. According to the generalized linear model, temperature affected (p<0.05) the presence of Legionella regardless of the species or the water supply (hot or cold). Additionally, opportunistic (P. aeruginosa) or non-opportunistic (E. coli, coliforms) pathogens were significantly associated (p<0.05) with the presence of all Legionella species. Temperature also exhibited a positive effect to all pathogens tested except for Pseudomonas according to the linear model. Multivariate analysis showed that Pseudomonas, total coliforms, HPC and temperature had a statistically significant effect on the presence of Legionella. Based on a binomial model, cold water had a positive effect on Legionella. Type of sampling and proximity of the sample to the boiler seemed to pose different effect on Legionella depending on the cfu/L. The number of hotel stars and rooms did not appear to have any effect in all tested models. Collectively, these results indicate the need for development of individualized water safety plans tailored by the presence of other microbiological agents, and unique physico-chemical factors, which could facilitate the survival of Legionella.in hotel water systems.

Fracture-related infection: Analysis of healthcare utilisation and associated costs

AimsA consensus definition of fracture related infection (FRI) has been created with the aim of standardising diagnosis and eliminating heterogeneity that prevents accurate comparison between existing studies. FRI remains one of the most challenging complications in musculoskeletal trauma surgery and carries with it a significant cost burden. A review of UK finances has not been completed utilising consensus diagnostic criteria. The goal of this study was to investigate the hospital-associated healthcare cost related to the treatment of FRI within an NHS major trauma centre. MethodThrough retrospective case-control analysis, 1240 patients with close fractures were identified. Of those, 21 patients with FRI were compared to 63 uninfected patients. Patients were matched based on fracture location, type of procedure and proximity in age. The costs assessed included hospitalisation, imaging, outpatient consultation, pharmaceuticals and procedure charges. Cost data was retrieved from healthcare resource group (HRG) guidelines, NHS Business Service Authority's (NBSA) prescription rates and internal costing. ResultsThe FRI group were found to incur a 2.51 increase in total medial healthcare cost compared to the control group (£22,058 vs £8798 [p < 0.001]), which was primarily due to increased procedural costs (£13,020 vs £6291 [p < 0.001]) and length of hospital stay (£7552 vs £2124 [p < 0.001]). ConclusionWhilst diagnosis of FRI has a more rigorous definition following the new consensus, prevalence and cost outcomes are similar to previous studies. Given the deficiency in funding and ongoing challenges of resource allocation to the NHS, it is prudent to incorporate studies such as this into stratifying departmental budgets and quality improvement. Level of evidenceIII.

Shaping online and offline informal learning networks in off-site construction projects: a proximity perspective

PurposeInformal learning networks are critical to response to calls for practitioners to reskill and upskill in off-site construction projects. With the transition to the coronavirus disease 2019 (COVID-19) pandemic, social media-enabled online knowledge communities play an increasingly important role in acquiring and disseminating off-site construction knowledge. Proximity has been identified as a key factor in facilitating interactive learning, yet which type of proximity is effective in promoting online and offline knowledge exchange remains unclear. This study takes a relational view to explore the proximity-related antecedents of online and offline learning networks in off-site construction projects, while also examining the subtle differences in the networks' structural patterns.Design/methodology/approachFive types of proximity (physical, organizational, social, cognitive and personal) between projects members are conceptualized in the theoretical model. Drawing on social foci theory and homophily theory, the research hypotheses are proposed. To test these hypotheses, empirical case studies were conducted on two off-site construction projects during the COVID-19 pandemic. Valid relational data provided by 99 and 145 project members were collected using semi-structured interviews and sociometric questionnaires. Subsequently, multivariate exponential random graph models were developed.FindingsThe results show a discrepancy arise in the structural patterns between online and offline learning networks. Offline learning is found to be more strongly influenced by proximity factors than online learning. Specifically, physical, organizational and social proximity are found to be significant predictors of offline knowledge exchange. Cognitive proximity has a negative relationship with offline knowledge exchange but is positively related to online knowledge exchange. Regarding personal proximity, the study found that the homophily effect of hierarchical status merely emerges in offline learning networks. Online knowledge communities amplify the receiver effect of tenure. Furthermore, there appears to be a complementary relationship between online and offline learning networks.Originality/valueProximity offers a novel relational perspective for understanding the formation of knowledge exchange connections. This study enriches the literature on informal learning within project teams by revealing how different types of proximity shape learning networks across different channels in off-site construction projects.

Local calcium signal transmission in mycelial network exhibits decentralized stress responses.

Many fungi live as mycelia, which are networks of hyphae. Mycelial networks are suited for the widespread distribution of nutrients and water. The logistical capabilities are critical for the extension of fungal survival areas, nutrient cycling in ecosystems, mycorrhizal symbioses, and virulence. In addition, signal transduction in mycelial networks is predicted to be vital for mycelial function and robustness. A lot of cell biological studies have elucidated protein and membrane trafficking and signal transduction in fungal hyphae; however, there are no reports visualizing signal transduction in mycelia. This paper, by using the fluorescent Ca2+ biosensor, visualized for the first time how calcium signaling is conducted inside the mycelial network in response to localized stimuli in the model fungus Aspergillus nidulans. The wavy propagation of the calcium signal inside the mycelium or the signal blinking in the hyphae varies depending on the type of stress and proximity to the stress. The signals, however, only extended around 1,500 μm, suggesting that the mycelium has a localized response. The mycelium showed growth delay only in the stressed areas. Local stress caused arrest and resumption of mycelial growth through reorganization of the actin cytoskeleton and membrane trafficking. To elucidate the downstream of calcium signaling, calmodulin, and calmodulin-dependent protein kinases, the principal intracellular Ca2+ receptors were immunoprecipitated and their downstream targets were identified by mass spectrometry analyses. Our data provide evidence that the mycelial network, which lacks a brain or nervous system, exhibits decentralized response through locally activated calcium signaling in response to local stress.

Long-term results of liver transplantation for maple syrup urine disease: A single-center experience in Turkey.

Maple syrup urine disease (MSUD) is an autosomal recessive inherited disorder. Despite the advances in medical nutrition therapies, classical phenotype causes severe neurological disorders and sudden death. It is known that MSUD patients do not experience metabolic attacks despite their free diet after liver transplantation (LT). This study aims to reveal the long-term results, development, mental, motor, intellectual and nutritional status of MSUD patients who underwent LT. The data of 12 patients who underwent deceased donor (5 recipients) and living donor liver transplantation (7 recipients) were retrospectively analyzed. The age, genotype, psychometric and mental status, development, BCAA values, type of LT, donor-recipient proximity, complications, and survival were assessed. There were 4 (33%) girls and 8 (67%) boys. The mean current age was 9.33 ± 4.58 years. The mean follow-up time was 3 ± 2.5 years. The repeated measures of leucine and isoleucine values revealed that there were no significant differences from the pre-LT to post-LT 1-year. The protein-restricted nutrition was switched to a free diet when oral intake was opened after LT. None of the recipients experienced metabolic attacks after the living donor or deceased donor LT. The 1-, 3-, and 5-year survival rate of the patients is 83.3%. There was no significant difference in survival between living and deceased donor liver transplantation. Liver transplantation is a treatment option for MSUD in proper conditions to save the patient life, increase the quality of life, and provide essential amino acids with free diet intake for growth and development.

Early Seizures during Stroke

INTRODUCTION: The connections between seizures and stroke, their characteristics and features are barely developed and also very important for the outcome. The diagnostic problem leads to ineffective treatment due to difficult selection of patients who are subject to prevention with antiepileptic drugs (AEDs) on one hand. On the other hand, is impossible to exam every stroke patient by EEG. We need an algorithm for screening indicated patients and conducting the EEG. After that we can include properly AED as a prevention. Their low frequency makes them time consuming to study.&#x0D; AIM: To conduct an epidemiological study of early epileptic seizures at the acute stroke phase and to derive principles for screening, diagnosis and behavior for prevention.&#x0D; CONTINGENT AND DESIGN: To achieve the goal we`ve researched retrospective patients, totally amounting to 656.&#x0D; RESULTS AND DISCUSSION: The factors identified so far in the genesis of seizures such as age, type and location of cerebrovascular accident and proximity to the cortex do not act alone, but in combination with undiscovered ones.&#x0D; CONCLUSIONS: There are no clear criteria to outline the rules for the AED prophylactic in patients with cerebrovascular disease (CVD). The most important indicator is the systematic assessment of the risk of seizures in the course of the disease. Patients at high risk of triggering seizures and developing epilepsy in CVDs are suitable for EEG examinations with a view to timely diagnosis and treatment.

From the Crowded Valleys to the Preserved Summits: Mountain Sports Participants' Attitudes Toward Protected Areas in the Sprawling Urban Areas of the Northern French Alps

Managing the flow of visitors in protected areas of the northern French Alps has become a central issue due to inhabitants' growing interest in mountain sports. This article presents the findings of a survey of mountain sports participants involving 1883 respondents in 4 mountain massifs. We inquired about their knowledge of the recreation spot (protection statuses and wildlife) and their attitudes toward restricting access to minimize wildlife disturbance. Respondents had better knowledge of wildlife than of protection statuses. Although they supported measures that aim to reduce disturbance, they believed access to the mountains should not be restricted. Type of activity, mountain site, and proximity of residence to recreation spots all influenced knowledge and attitudes. These results should encourage managers to target visitors differently based on what they do and where they come from to ensure compliance with regulations and tranquility of wildlife.

Organ Donation in Romanian Online Media

Mass media represents the primary source of information about organ donation for the general public. The present study explored the content of Romanian online media concerning organ donation. We conducted a content analysis of 313 media materials published online between October 2012 and October 2019 in Romanian. The coding categories were year of publication, media outlet, type of material, type of evidence, valence, topic, and proximity of the story. A semestral web-search was conducted between February 2016 and November 2019. The analysis revealed that the Romanian online coverage of organ donation was modest across time. Regarding the valence, results indicated that 57.2% of the materials presented organ donation in a positive way, 14.1% were neutral, 12.5% were negative, whereas 16.3% of the materials were mixed. Moreover, the valence of the materials varied across media outlets, proximity of the story and publication year. Promotion, information about organ donation and system were the topics that occurred most frequently, followed by events, policy, and legal categories. Findings provide insight into how media may shape people's opinions about organ donation. The study also contributes to understanding the Romanian organ donation macro-social environment and provides valuable information for practice.

Effect of the Solvent and Substituent on Tautomeric Preferences of Amine-Adenine Tautomers.

Adenine is one of the basic molecules of life; it is also an important building block in the synthesis of new pharmaceuticals, electrochemical (bio)sensors, or self-assembling molecular materials. Therefore, it is important to know the effects of the solvent and substituent on the electronic structure of adenine tautomers and their stability. The four most stable adenine amino tautomers (9H, 7H, 3H, and 1H), modified by substitution (C2– or C8−) of electron-withdrawing NO2 and electron-donating NH2 groups, are studied theoretically in the gas phase and in solvents of different polarities (1 ≤ ε < 109). Solvents have been modeled using the polarizable continuum model. Comparison of the stability of substituted adenine tautomers in various solvents shows that substitution can change tautomeric preferences with respect to the unsubstituted adenine. Moreover, C8 substitution results in slight energy differences between tautomers in polar solvents (<1 kcal/mol), which suggests that in aqueous solution, C8–X-substituted adenine systems may consist of a considerable amount of two tautomers—9H and 7H for X = NH2 and 3H and 9H for X = NO2. Furthermore, solvation enhances the effect of the nitro group; however, the enhancement strongly depends on the proximity effects. This enhancement for the NO2 group with two repulsive N···ON contacts can be threefold higher than that for the NO2 with one attractive NH···ON contact. The proximity effects are even more significant for the NH2 group, as the solvation may increase or decrease its electron-donating ability, depending on the type of proximity.

Practice patterns surrounding referral to a specialty venous thromboembolism (VTE) clinic: a retrospective review.

This study audited prescribing practices for patients with acute venous thromboembolism (VTE) prior to and after being seen in an outpatient VTE clinic. This retrospective chart review conducted between June 2018 through May 2019 included patients with confirmed acute VTE, seen for an initial appointment. Exclusion criteria were patients with additional indications for anticoagulation, lack of information to determine primary outcome and active cancer. To assess practices, the time taken to be seen in clinic, anticoagulant therapies (prior to/following clinic) used and concordance of anticoagulant use with product monographs were assessed. Of the 325 (40.6%) patients included, the median age was 57.7 years, most were referred with pulmonary embolism (PE) (54.5%) and the majority of referrals came through the emergency department (45.2%). The median time to be seen in clinic was 13 days, with no differences in time between type of VTE or proximity of clot. Prior to being seen in VTE clinic, most were prescribed direct oral anticoagulants (DOACs) (81.9%), with a small portion receiving low molecular weight heparin (LMWH) (12.9%) and warfarin (5.2%). Most received anticoagulants concordant with product monographs (87.7%), with more discordance with warfarin (52.9%) and LMWH (14.3%) compared to DOACs (9.4%) (P < 0.001). At the initial VTE clinic visit, 70 (21.5%) patients had therapy changes, with most being from LMWH/warfarin to a DOAC (47.1%). Our data reflects high uptake of DOACs for acute VTE treatment with most prescribed in accordance with product monographs.

Resistance is not futile: The use of projections for resistance joining of metal additively and conventionally manufactured parts

Metal additive manufacturing processes can produce geometrically complex and lightweight components. While conventionally manufactured components are frequently assembled to form larger parts, additive manufacturing can be used to print an entire part without needing any assembly. However, additive manufacturing processes are frequently limited in the size of the part they can produce, and it is often more economically favourable to conventionally manufacture larger or simpler geometries, such as large sheets. In this study, we demonstrate the use of a resistance joining process to facilitate the assembly of additive manufactured components. Projections are designed into additive manufactured parts to allow for joining with a conventional metal sheet. Joint performance is evaluated as a function of design choices, including the type of infill, part thickness, and proximity to adjacent joints, as well as the resistance joining process parameters. High strength joints capable of withstanding an applied torque of up to 80 Nm were obtained and functional parts were assembled to a conventionally manufactured sheet as a demonstration of the process. Incorporating projections for resistance joining into the design stage of additive manufactured parts has the potential to facilitate the use of additive manufactured components in larger assemblies and broaden the adoption of additive manufacturing in industry.

Multi-Stage Network Embedding for Exploring Heterogeneous Edges

The relationships between objects in a network are typically diverse and complex, leading to the heterogeneous edges with different semantic information. In this article, we focus on exploring the heterogeneous edges for network representation learning. By considering each relationship as a view that depicts a specific type of proximity between nodes, we propose a multi-stage non-negative matrix factorization (MNMF) model, committed to utilizing abundant information in multiple views to learn robust network representations. In fact, most existing network embedding methods are closely related to implicitly factorizing the complex proximity matrix. However, the approximation error is usually quite large, since a single low-rank matrix is insufficient to capture the original information. Through a multi-stage matrix factorization process motivated by gradient boosting, our MNMF model achieves lower approximation error. Meanwhile, the multi-stage structure of MNMF gives the feasibility of designing two kinds of non-negative matrix factorization (NMF) manners to preserve network information better. The united NMF aims to preserve the consensus information between different views, and the independent NMF aims to preserve unique information of each view. Concrete experimental results on realistic datasets indicate that our model outperforms three types of baselines in practical applications.

The Observed Quality of Caregiver-Child Interactions With and Without a Mobile Screen Device.

This study investigated how caregivers' mobile device use influenced the quality of their interactions with their children. The associations between quality of interactions and the type of activity (eg, typing/swiping, looking at screen), setting, caregiver-child proximity, and child behaviors were also examined. Researchers anonymously and systematically observed and coded the behavior of 98 caregiver-child dyads in public settings (eg, parks, food courts) during real-time, naturally occurring interactions using time sampling. Caregivers who used a mobile device for the entire observation engaged in less joint attention and were less responsive than caregivers who used the device some of the time. When looking at patterns within caregivers who used the device intermittently, the probability that they would engage in joint attention, initiate interactions with their child, talk, and display positive emotions was lower when they used a mobile device than when they did not. Child talking and positive affect were unrelated to caregiver device use. Activity type with the device, caregiver-child proximity and setting also related to interaction quality. Caregiver device use was negatively associated with adult behaviors that are key components of high-quality caregiver-child interactions. Additionally, setting, activity type, and caregiver-child proximity are factors that should be considered because they relate to the quality of caregiver-child interactions in the context of mobile screen technologies.

Network structures in the development of entrepreneurial practices in beekeeping of Primorsky Krai of the late XIX – early XX centuries

The subject of this research is determination of the network interaction on the background of growth of entrepreneurial activity in the area of beekeeping in Primorsky Krai during late XIX &amp;ndash; early XX centuries, as well as the interconnection between expansion of economic impact in entrepreneurship and functionality of social networks. &amp;nbsp;The tasks of this study include identification and description of network structures, determination of the type of proximity on which they are based, and clarification of the specificity of the impact of network interaction upon development of beekeeping of Primorsky Krai of the late XIX &amp;ndash; early XX centuries. Identification and description of network structures in this research is done using the tools of economic cartography, surveying, diachronic analysis, with reliance upon archival materials on inspection of peasant farms of Primorsky Krai in 1912. The scientific novelty of this research consists in revelation of the functionality of social networks in proliferation of new knowledge, economic practices and technologies. The work highlights two types of network structures, which depend on the type of proximity that underlies the interaction of economic agents. It is established that the development of beekeeping practice and entrepreneurship based on production of honey relates to the functionality of the network structures.

A Hybrid GIS and AHP Approach for Modelling Actual and Future Forest Fire Risk Under Climate Change Accounting Water Resources Attenuation Role

Forest wildfires usually occur due to natural processes such as lightning and volcanic eruptions, but at the same time they are also an effect of uncontrolled and illegal anthropogenic activities. Different factors can influence forest wildfires, like the type of vegetation, morphology, climate, and proximity to human activities. A precise evaluation of forest fire issues and of the countermeasures needed to limit their impact could be satisfactory especially when forest fire risk (FFR) mapping is available. Here, we proposed an FFR evaluation methodology based on Geographic Information System (GIS) and the analytic hierarchy process (AHP). The study area is the Campania region (Southern Italy) that, for the last 30 years, has been affected by numerous wildfires. The proposed methodology analyzed 12 factors, and AHP was used for weight assignment, offering a new approach to some parameters. The method divided the study area into five risk classes, from very low to very high. Validation with fire alerts showed a good correlation between observed and predicted fires (0.79 R2). Analyzing the climate projections, a future FFR for 2040 was also assessed. The proposed methodology represents a reliable screening tool to identify areas under forest fire risk, and can help authorities to direct preventive actions.

Types of interaction in the triad mother–child–father at the threat of preterm birth at the last trimester of pregnancy and after the birth as a criterion of differentiation of the measures of their medical-psychological support

The study involved 150 women at 23–37 weeks of pregnancy: 120 women with the threat of premature birth (main group, MG), 30 women with the physiological course of pregnancy (comparison group, CG) and their husbands. The types of interaction in the mother–child–father triad with the threat of premature birth and after childbirth have been studied. A psychodiagnostic study revealed a reliably high level of the average value of reactive and personal anxiety in women with MG. The average indicator of the level of depression is higher in the MG, where there are cases of subdepressive state and severe depression, in the CG the latter was not revealed. According to the Cranley scale, at the first stage of the study, the level of attachment to the fetus in women from MG was (71,0±1,0) points (attachment disorder), in women from CG was (51,0±2,0) points (sufficient level of attachment), p&lt;0,05. With the help of the «Pregnant Attitude Test», the prevailing type of woman’s attitude to her unborn child was determined in terms of the course of pregnancy. It was found that in 20,8 % of women, the euphoric type predominates, 9,17 % had the optimal type, 9,17 % had hyponosognosic type, 2,5 % had anxious type, 3,33 % had depressive type. In 26,7 % of women, CG has the optimal type. There are no other types of attitudes towards pregnancy. In women with MG, disorientation prevails at all stages of the examination (41–46 people), the dependent type (35–36), autonomous (23–29), and avoidance of proximity much less often was (14–16), in women with CG, the autonomous type dominates (10–13), dependent type (8–10), and avoidance of proximity (4–9) little less often were and disorientation (3–4) much less often was. At each stage of the survey, the level of social support in the MG is reduced relative to that in the CG. It is noted that in both groups the level of social support on two scales such as the support of colleagues at work and public organizations is reduced.

Multi-label classification of Indonesian news topics using Pseudo Nearest Neighbor Rule

News is a form of text data that must be categorized to facilitate retrieval of information for the reader. One problem that arises when categorizing news is the many topics that news can discuss, which is known as a multi-label condition. To solve this problem, a system that can perform multi-label classification using a Pseudo Nearest Neighbor Rule (PNNR) algorithm—a variant of the k-Nearest Neighbor (k-NNR) algorithm—was developed in this study. This system yielded a cross-validation error of 0,1495, measured using the hamming loss method via Cosine proximity. From the experiment, it can be concluded that the performance of the PNNR algorithm is influenced by the type of proximity used and the number of nearest neighbors.

Individual preferences for physical exercise as secondary prevention for non-specific low back pain: A discrete choice experiment.

BackgroundExercise is effective in improving non-specific low back pain (LBP). Certain components of physical exercise, such as the type, intensity and frequency of exercise, are likely to influence participation among working adults with non-specific LBP, but the value and relative importance of these components remain unknown. The study’s aim was to examine such specific components and their influence on individual preferences for exercise for secondary prevention of non-specific LBP among working adults.MethodsIn a discrete choice experiment, working individuals with non-specific LBP answered a web-based questionnaire. Each respondent was given ten pairs of hypothetical exercise programs and asked to choose one option from each pair. The choices comprised six attributes of exercise (i.e., type of training, design, intensity, frequency, proximity and incentives), each with either three or four levels. A conditional logit regression that reflected the random utility model was used to analyze the responses.ResultsThe final study population consisted of 112 participants. The participants’ preferred exercise option was aerobic (i.e., cardiovascular) rather than strength training, group exercise with trainer supervision, rather than individual or unsupervised exercise. They also preferred high intensity exercise performed at least once or twice per week. The most popular types of incentive were exercise during working hours and a wellness allowance rather than coupons for sports goods. The results show that the relative value of some attribute levels differed between young adults (age ≤ 44 years) and older adults (age ≥ 45 years) in terms of the level of trainer supervision required, exercise intensity, travel time to exercise location and financial incentives. For active study participants, exercise frequency (i.e., twice per week, 1.15; CI: 0.25; 2.06) influenced choice of exercise. For individuals with more than one child, travel time (i.e., 20 minutes, -0.55; CI: 0.65; 3.26) was also an influential attribute for choice of exercise, showing that people with children at home preferred to exercise close to home.ConclusionsThis study adds to our knowledge about what types of exercise working adults with back pain are most likely to participate in. The exercise should be a cardiovascular type of training carried out in a group with trainer supervision. It should also be of high intensity and preferably performed twice per week during working hours. Coupons for sports goods do not appear to motivate physical activity among workers with LBP. The findings of the study could have a substantial impact on the planning and development of exercise provision and promotion strategies to improve non-specific LBP. Providers and employers may be able to improve participation in exercise programs for adults with non-specific LBP by focusing on the exercise components which are the most attractive. This in turn would improve satisfaction and adherence to exercise interventions aimed at preventing recurrent non-specific LBP.

Segmentation of consumer markets in the US: What do intercity price differences tell us?

AbstractWe quantify the magnitude of market segmentation in US consumer market and explore the underlying factors behind this segmentation, using a quarterly panel of retail prices for 45 products in 48 US cities from 1985 to 2009. The extent of market segmentation is estimated using city‐pair price differences within the framework of both linear autoregressive (AR) and nonlinear threshold autoregressive (TAR) models. We find that the magnitude of market segmentation varies from one product to another, but even more across city pairs in each product. Contrary to a widespread perception, market segmentation within the US is not necessarily larger for non‐tradable services compared to tradable goods. We identify potential drivers of market segmentation by relating the cross‐city and cross‐product variations of market segmentation to location‐specific and product‐specific characteristics—distance, relative city sizes, differences in wage and rent, type of product and proximity to marketplace. Distance, which captures more than transport costs, turns out to be the most salient factor even after controlling for a range of other potential factors. The effect of distance, however, varies substantially across products, with perishable products and locally produced products showing larger distance effect on market segmentation. We find that the magnitude of market segmentation has been somewhat stable during the sample period, but intercity price differences have become more sensitive to distance over time in many products under study.