395 research outputs found

    New parity results of sums of partitions and squares in arithmetic progressions

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    Recently, Ballantine and Merca proved that if (a,b)∈{(6,8), (8,12), (12,24), (15,40),(16,48), (20,120), (21,168)} (a,b) \in \{(6,8),\ (8,12),\ (12,24),\ (15,40),\\ (16,48),\ (20,120),\ (21,168)\}, then ∑ak+1 squarep(n−k)≡1 (mod 2)\sum_{ak+1 \ {\rm square}}p(n-k)\equiv 1\ ({\rm mod}\ 2) if and only if bn+1bn+1 is a square. In this paper, we investigate septuple (a1,a2,a3,a4,a5,a6,a7)∈N5×Q2(a_1,a_2,a_3,a_4,a_5,a_6,a_7)\in \mathbb{N}^5\times \mathbb{Q}^2 for which ∑a1k+a2 squarep(a3a4αn+a6a4α+a7−k)≡1 (mod 2)\sum_{a_1k+a_2 \ {\rm square}}p(a_3a_4^\alpha n+a_6 a_4^\alpha+a_7-k) \equiv 1\ ({\rm mod}\ 2) if and only if a5n+1a_5n+1 is a square. We prove some new parity results of sums of partitions and squares in arithmetic progressions which are analogous to the results due to Ballantine and Merca

    ONLINE RETAIL KEYWORD CHARACTERISTICS AND SEARCH MARKETING PERFORMANCE

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    To make judicious budget and resource allocation decisions, it is essential to understand the characteristics and performance of keywords used by target shoppers. Taking the approach of understanding consumers’ information needs, we construct a goal-related keyword characterization framework. Most search keywords exhibit more than one of the following characteristics - retailer specific, brand specific, product specific, feature related, or shopping intention. We analyze search engine ranking, click-through, and revenue data associated with visitor-disclosed search keywords from a top Web-only retailer over one year. Our findings show the interesting impacts of both keyword characteristics and dual-appearance of paid and organic advertisements on search marketing performance. The contributions of the research include a comprehensive search keyword characterization framework, and the analysis of the relationships between keyword characteristics and search performance. These findings have strong implications for search marketing decisions

    Adiposity and weight change in mid-life in relation to healthy survival after age 70 in women: prospective cohort study

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    Objective: To examine the hypothesis that mid-life adiposity is associated with a reduced probability of maintaining an optimal health status among those who survive to older ages. Design: Prospective cohort study. Setting: The Nurses’ Health Study, United States. Participants: 17 065 women who survived until at least the age of 70, provided information on occurrence of chronic disease, cognitive function, physical function, and mental health at older ages, and were free from major chronic diseases at mid-life (mean age was 50 at baseline in 1976). Main outcome measures: Healthy survival to age 70 and over was defined as having no history of 11 major chronic diseases and having no substantial cognitive, physical, or mental limitations. Results: Of the women who survived until at least age 70, 1686 (9.9%) met our criteria for healthy survival. Increased body mass index (BMI) at baseline was significantly associated with linearly reduced odds of healthy survival compared with usual survival, after adjustment for various lifestyle and dietary variables (P<0.001 for trend). Compared with lean women (BMI 18.5-22.9), obese women (BMI ≥30) had 79% lower odds of healthy survival (odds ratio 0.21, 95% confidence interval 0.15 to 0.29). In addition, the more weight gained from age 18 until mid-life, the less likely was healthy survival after the age of 70. The lowest odds of healthy survival were among women who were overweight (BMI ≥25) at age 18 and gained ≥10 kg weight (0.18, 0.09 to 0.36), relative to women who were lean (BMI 18.5-22.9) and maintained a stable weight. Conclusions: These data provide evidence that adiposity in mid-life is strongly related to a reduced probability of healthy survival among women who live to older ages, and emphasise the importance of maintaining a healthy weight from early adulthood

    A Framework for Investigating Impacts of Telemedicine

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    Web Mining-Based Objective Metrics for Measuring Website Navigatability

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    Web site design is critical to the success of electronic commerce and digital government. Effective design requires appropriate evaluation methods and measurement metrics. The current research examines Web site navigability, a fundamental structural aspect of Web site design. We define Web site navigability as the extent to which a visitor can use a Web site’s hyperlink structure to locate target contents successfully in an easy and efficient manner. We propose a systematic Web site navigability evaluation method built on Web mining techniques. To complement the subjective self-reported metrics commonly used by previous research, we develop three objective metrics for measuring Web site navigability on the basis of the Law of Surfing. We illustrate the use of the proposed methods and measurement metrics with two large Web sites

    The Regulation of Commercial Profiling — A Comparative Analysis

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    The authors, all data protection experts, discuss the status of the relevant data protection regulatory framework on profiling in the business sector in sev eral countries worldwide, from the constitutional level to some individual regulation including the general attitude towards the topic. The EU perspective is presented on the basis of the present directives as well as the General Data Protection Regulation. The United Kingdom, Germany and France, as three of the largest EU Member States with partly highly differing regulatory approaches represent Member State law. Australia, Brazil and the US regulation exemplify the different integration of data protection standards and different models of approaching pro filing in the globalised IT world

    Data Hiding with Deep Learning: A Survey Unifying Digital Watermarking and Steganography

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    Data hiding is the process of embedding information into a noise-tolerant signal such as a piece of audio, video, or image. Digital watermarking is a form of data hiding where identifying data is robustly embedded so that it can resist tampering and be used to identify the original owners of the media. Steganography, another form of data hiding, embeds data for the purpose of secure and secret communication. This survey summarises recent developments in deep learning techniques for data hiding for the purposes of watermarking and steganography, categorising them based on model architectures and noise injection methods. The objective functions, evaluation metrics, and datasets used for training these data hiding models are comprehensively summarised. Finally, we propose and discuss possible future directions for research into deep data hiding techniques

    Investigating physician acceptance of telemedicine technology: A survey study in Hong Kong

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    Fast-growing interest in telemedicine and increased investment in its enabling technology have made physician technology acceptance a growing concern for development and management of telemedicine. In this study, we used Theory of Planned Behavior to investigate technology acceptance by physicians who practiced in public tertiary hospitals in Hong Kong. Our data supported the investigated theory, whose explanatory power of physicians' technology acceptance was moderate, however. Overall, physicians showed positive attitudes towards use of telemedicine technology and exhibited moderate intention to use it, particularly for clinical tasks. Furthermore, several implications for development and management of telemedicine can also be drawn from the findings.published_or_final_versio

    Distinct effects of apathy and dopamine on effort-based decision making in Parkinson’s disease

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    Effort-based decision making is a cognitive process crucial to normal motivated behaviour. Apathy is a common and disabling complication of Parkinson’s disease, but its aetiology remains unclear. Intriguingly, the neural substrates associated with apathy also sub-serve effort-based decision making in animal models and humans. Furthermore, the dopaminergic system plays a core role in motivating effortful behaviour for reward, and its dysfunction has been proposed to play a crucial role in the aetiology of apathy in Parkinson’s disease. We hypothesised that disrupted effort-based decision making underlies the syndrome of apathy in Parkinson’s disease, and that this disruption may be modulated by the dopaminergic system. An effort-based decision making task was administered to 39 patients with Parkinson’s disease, with and without clinical apathy, ON and OFF their normal dopaminergic medications across two separate sessions, as well as 32 healthy age- and gender-matched controls. On a trial-by-trial basis participants decided whether to accept or reject offers of monetary reward in return for exerting different levels of physical effort via handheld, individually calibrated dynamometers. Effort and reward were manipulated independently, such that offers spanned the full range of effort/reward combinations. Apathy was assessed using the Lille apathy rating scale. Motor effects of the dopamine manipulation were assessed using the UPDRS part three motor score. The primary outcome variable was choice (accept/decline offer). analysed using a hierarchical generalised linear mixed effects model, and the vigour of squeeze (Newtons exerted above required force). Both apathy and dopamine depletion were associated with reduced acceptance of offers. However, these effects were driven by dissociable patterns of responding. While apathy was characterised by increased rejection of predominantly low reward offers, dopamine increased responding to high effort, high reward offers, irrespective of underlying motivational state. Dopamine also exerted a main effect on motor vigour, increasing force production independently of reward offered, while apathy did not affect this measure. The findings demonstrate that disrupted effort based decision making underlies Parkinson’s disease apathy, but in a manner distinct to that caused by dopamine depletion. Apathy is associated with reduced incentivisation by the rewarding outcomes of actions. In contrast, dopamine has a general effect in motivating behaviour for high effort, high reward options without altering the response pattern that characterises the apathetic state. Thus the motivational deficit observed in Parkinson’s disease appears not to be simply secondary to dopaminergic depletion of mesocorticolimbic pathways, suggesting non-dopaminergic therapeutic strategies for apathy may be important future targets
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