We propose a parallel algorithm for computing exact solutions to the problem of minimizing the number of multileaf collimator apertures needed in step-and-shoot intensity modulated radiotherapy. ...These problems are very challenging particularly as the problem size increases. Here, we investigate how advanced parallel computing methods can be applied to these problems with a focus on the issues that are peculiar to parallel search algorithms and do not arise in their serial counterparts. A previous paper by the authors presented the MU–RD method for solving such problems using a serial constraint programming based search method. This method is being used as the starting point for a parallel implementation. The key challenges in creating a parallel implementation are ensuring that the CPUs are not starved of work and avoiding unnecessary computation due to the rearrangement of the search order in the parallel version. We show that efficient parallel optimisation is possible by dynamically changing the way work is split with potentially multiple tree search processes as well as parallel search of nodes. A weakly sorted queueing system is used to ensure appropriate prioritisation of tasks. Numerical results are presented to demonstrate the effectiveness of our algorithms in scaling from 8 to 64 CPUs.
Mapping infant neurocognitive differences that precede later ADHD-related behaviours is critical for designing early interventions. In this study, we investigated (1) group differences in a battery ...of measures assessing aspects of attention and activity level in infants with and without a family history of ADHD or related conditions (ASD), and (2) longitudinal associations between the infant measures and preschool ADHD traits at 3 years. Participants (
= 151) were infants with or without an elevated likelihood for ADHD (due to a family history of ADHD and/or ASD). A multi-method assessment protocol was used to assess infant attention and activity level at 10 months of age that included behavioural, cognitive, physiological and neural measures. Preschool ADHD traits were measured at 3 years of age using the Child Behaviour Checklist (CBCL) and the Child Behaviour Questionnaire (CBQ). Across a broad range of measures, we found no significant group differences in attention or activity level at 10 months between infants with and without a family history of ADHD or ASD. However, parent and observer ratings of infant activity level at 10 months were positively associated with later preschool ADHD traits at 3 years. Observable behavioural differences in activity level (but not attention) may be apparent from infancy in children who later develop elevated preschool ADHD traits.
Consumers with celiac disease are discouraged from eating fried foods cooked in shared fryers with wheat-containing foods at restaurants based on presumed gluten exposure. The purpose of the present ...study is to assess gluten levels of fries free of gluten-containing ingredients cooked in shared fryers with wheat.
20 orders of fries were purchased from 10 different restaurants. Restaurants confirmed that fries and oil were free of gluten-containing ingredients. All restaurants confirmed that their fryers were used to cook wheat-containing foods. Fries were sent to Bia Diagnostics and tested in 1-gram duplicates using the R7001 sandwich R5 ELISA and the R7021 competitive R5 ELISA. A microwave control also was run.
The sandwich ELISA found gluten in 9/20 fry orders (7 to > 80 ppm). The competitive ELISA found gluten in 3/20 fry orders (14 to > 270 ppm). In the microwave control (60-ppm gluten mixture of wheat flour and canola oil), the unheated mixture tested at a mean level of 64 ppm gluten using the sandwich ELISA and 137 ppm gluten using the competitive ELISA. The mixture heated to 190°C tested at a mean level of 55 ppm gluten using the sandwich ELISA and < 10 ppm and 16 ppm gluten using the competitive ELISA.
Based on test results, 25% of fry orders would not be considered gluten-free.
Gluten cross contact may occur when gluten-free foods are cooked in shared fryers with wheat. ELISAs may underperform when analyzing for gluten that has been heated.
The emergence of work under what can broadly be termed 'platform capitalism' has coincided with a series of parallel developments in industrial practice and technologies in the United Kingdom. Over ...the past three decades or so there has been a dramatic flexibilization of the labor market through a combination of deregulation, the normalization of atypical working patterns and an explosion in self-employment.1 The recent genesis of the so-called 'gig economy' can be seen as the apotheosis of these processes, in which workers are, ostensibly, recruited to complete discrete tasks, whether for the same or different end-users, rather than engaged in a single overarching relational contractual nexus.2 The United Kingdom has seen an explosion in these forms of working practice,3 in particular within certain industries and among certain demographic groups, notably younger workers.4The emergence of platforms, that is digital applications or systems which take advantage of data and technologies such as geo-location to connect disparate groups, is a separate phenomenon to the emergence of the gig economy. For instance, social media networks such as Facebook are platform-based services which connect users with each other and with advertisers, with no necessary link to changing working models. Equally, such platforms can be used within enterprises to distribute work and liaise with customers with no discernible impact on the relationship with the employee in terms of employment status or protections. However, many new iterations of gig working in the United Kingdom have emerged primarily through the use of platforms to the extent that the two are often thought of as being inherently linked phenomena. In particular, these processes have led to a great number of business models which have been able to externalize work functions, disrupting the Coasean vision of the firm and the place of the worker within it.5 Caution should be exercised in this regard, however. Not only are the emerging forms of work extremely heterogeneous in nature, they also interact in different ways with various aspects of the digital economy and information technology.
In this paper, we introduce an exact method based on constraint programming ideas for a combinatorial optimization problem that arises from the treatment planning of intensity-modulated ...radiotherapy—the minimum cardinality problem (MCP). The MCP is to find a decomposition of a given integer matrix into a weighted sum of binary matrices with consecutive ones, such that the number of such binary matrices is minimised. We compare our method with two recent exact methods for the same problem and a recent exact method for a special case of the problem. Numerical results are presented that indicate that our method is computationally more efficient than the three existing methods.
Celotno besedilo
Dostopno za:
CEKLJ, DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The “Race Directive,” along with the rest of the recent European Union expansion of its body of equality law, was welcomed with huge acclaim and fanfare, predictably by the Commission, but also by ...much academic writing. Now that this has subsided, it is necessary to engage in a sober analysis of the contents of the directive. Although the directive has been seen as embodying a huge shift in conceptions of equality and discrimination, and as part of an emerging European social citizenship, a closer examination of the provisions of the directive reveals something quite different: an ambivalence towards broader reaching conceptions of equality, a repeating of the mistakes of the past, and a series of delegations of key decisions regarding the potentially most progressive aspects of the legislation to other actors. This article suggests that whereas the directive contains many positive aspects, to a large extent it represents an exercise in passing the buck, given the hollowness of many of the seemingly expansive provisions. This means that our focus must shift onto member states and other actors, who have traditionally been conspicuously inactive in the field of race discrimination.
Anorexia nervosa (AN) is associated with difficulties in social and emotional functioning. A significant proportion of individuals with AN show autistic traits, which may influence social attention. ...This study examined attention to faces and facial features in AN, recovered AN (REC), and healthy controls, as well as relationships with comorbid psychopathology. One hundred and forty-eight participants’ eye movements were tracked while watching a naturalistic social scene. Anxiety, depression, alexithymia, and autistic traits were assessed via self-report questionnaires. Participants with AN spent significantly less time looking at faces compared to REC and controls; patterns of attention to individual facial features did not differ across groups. Autistic traits mediated the relationship between group and time spent looking at faces.
Research suggests a relationship between anorexia nervosa and autism spectrum disorder. The aim of the current study was to examine social attention in anorexia nervosa and autism spectrum disorder ...compared with age- and sex-matched typically developing groups, and to examine whether lowered social motivation could explain reductions in social attention across the two disorders. Participants’ eye movements were tracked while watching a dynamic social scene. The proportion of fixation duration to faces, bodies and non-social areas of interest were compared across groups. Participants with autism spectrum disorder looked at faces significantly less often than controls, however, there were no differences between anorexia nervosa and controls in attention to faces. Typically developing -normed z-scores indicated that attention to faces showed the greatest deviation from normative data compared with body or non-social areas of interest in both autism spectrum disorder and anorexia nervosa, however, differences were larger in autism spectrum disorder than in anorexia nervosa. Social motivation scores did not predict attention to faces in either autism spectrum disorder or anorexia nervosa. Our results do not support the hypothesis that differences in social motivation underlie reduced social attention in both anorexia nervosa and autism spectrum disorder.
Lay abstract
Research suggests a relationship between autism and anorexia nervosa. For example, rigid and inflexible behaviour, a preference for routine and social difficulties are seen in both conditions. In this study, we examined whether people with anorexia and people with autism show similarities in social attention (where they look while engaging in social interactions or watching a scene with people interacting). This could help us understand why people with anorexia and autism experience difficulties in social situations. Participants with either anorexia or autism, as well as participants with no mental health problems watched a video of a social scene while we recorded which parts of the scene they looked at with an eye-tracker. Participants also completed questionnaires to assess characteristics of autism. We found that autistic participants looked at faces less than typically developing participants. However, participants with anorexia did not show a similar reduction in attention to faces, contrary to our predictions. Autistic features were not related to attention in either group. The results suggest that autistic people may miss important social cues (like facial expressions), potentially contributing to social difficulties. However, this mechanism does not appear explain social difficulties in people with anorexia.
PDF
