51,676 research outputs found
Transfer of a Polaritonic Qubit through a Coupled Cavity Array
We demonstrate a scheme for quantum communication between the ends of an
array of coupled cavities. Each cavity is doped with a single two level system
(atoms or quantum dots) and the detuning of the atomic level spacing and
photonic frequency is appropriately tuned to achieve photon blockade in the
array. We show that in such a regime, the array can simulate a dual rail
quantum state transfer protocol where the arrival of quantum information at the
receiving cavity is heralded through a fluorescence measurement. Communication
is also possible between any pair of cavities of a network of connected
cavities.Comment: Contribution to Special Issue in Journal of Modern Optics celebrating
the 60th birthday of Peter L. Knigh
Methodological Individualism, the We-mode, and Team Reasoning
Raimo Tuomela is one of the pioneers of social action theory and has done as much as anyone over the last thirty years to advance the study of social action and collective intentionality. Social Ontology: Collective Intentionality and Group Agents (2013) presents the latest version of his theory and applications to a range of important social phenomena. The book covers so much ground, and so many important topics in detailed discussions, that it would impossible in a short space to do it even partial justice. In this brief note, I will concentrate on a single, though important, theme in the book, namely, the claim that we must give up methodological individualism in the social sciences and embrace instead irreducibly group notions. I wish to defend methodological individualism as up to the theoretical tasks of the social sciences while acknowledging what is distinctive about the social world and collective intentional action.
Tuomela frames the question of the adequacy of methodological individualism in terms of a contrast between what he calls the I-mode and the we-mode. He argues that we-mode phenomena are not reducible to I-mode phenomena, and concludes that we must reject methodological individualism. I will argue that the irreducibility of the we-mode to the I-mode, given how the contrast is set up, does not entail the rejection of methodological individualism. In addition, I will argue that the three conditions that Tuomela places on genuine we-mode activities, the group reason, collectivity, and collective commitment conditions, if they are understood in a way that does not beg the question, can plausibly be satisfied by a reductive account. Finally, I will argue that the specific considerations advanced in the book do not give us reason to think that a reductive account cannot be adequate to the descriptive and explanatory requirements of a theory of the social worl
Random array of colour filters in the eyes of butterflies
The compound eye of the Japanese yellow swallowtail butterfly Papilio xuthus is not uniform, In a combined histological, electrophysiological and optical study, we found that the eye of P., xuthus has at least three different types of ommatidia, in a random distribution. In each ommatidium, nine photoreceptors contribute microvilli to the rhabdom, The distal two-thirds of the rhabdom length is taken up by the rhabdomeres of photoreceptors R1-R4, The proximal third consists of rhabdomeres of photoreceptors R5-R8, except for the very basal part, to which photoreceptor R9 contributes, In all ommatidia, the R1 and R2 photoreceptors have a purple pigmentation positioned at the distal tip of the ommatidia, The R3-R8 photoreceptors in any one ommatidium all have either yellow or red pigmentation in the cell body, concentrated near the edge of the rhabdom, The ommatidia with red-pigmented R3-R8 are divided into two classes: one class contains an ultraviolet-fluorescing pigment. The different pigmentations are presumably intimately related to the various spectral types found previously in electrophysiological studies.</p
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Reducing weight and increasing physical activity in people at high risk of cardiovascular disease: a randomised controlled trial comparing the effectiveness of enhanced motivational interviewing intervention with usual care.
OBJECTIVE: The epidemic of obesity is contributing to the increasing prevalence of people at high risk of cardiovascular disease (CVD), negating the medical advances in reducing CVD mortality. We compared the clinical and cost-effectiveness of an intensive lifestyle intervention consisting of enhanced motivational interviewing in reducing weight and increasing physical activity for patients at high risk of CVD. METHODS: A three-arm, single-blind, parallel-group randomised controlled trial was conducted in consenting primary care centres in south London. We recruited patients aged 40-74 years with a QRisk2 score ≥20.0%, which indicates the probability of having a CVD event in the next 10 years. The intervention was enhanced motivational interviewing which included additional behaviour change techniques and was delivered by health trainers in 10 sessions over 1 year, in either group (n=697) or individual (n=523) format. The third arm received usual care (UC; n=522). The primary outcomes were physical activity (mean steps/day) and weight (kg). Secondary outcomes were changes in low-density lipoprotein cholesterol and CVD risk score. We estimated the relative cost-effectiveness of each intervention. RESULTS: At 24 months, the group and individual interventions were not more effective than UC in increasing physical activity (mean difference=70.05 steps, 95% CI -288.00 to 147.90 and mean difference=7.24 steps, 95% CI -224.01 to 238.50, respectively), reducing weight (mean difference=-0.03 kg, 95% CI -0.49 to 0.44 and mean difference=-0.42 kg, 95% CI -0.93 to 0.09, respectively) or improving any secondary outcomes. The group and individual interventions were not cost-effective at conventional thresholds. CONCLUSIONS: Enhancing motivational interviewing with additional behaviour change techniques was not effective in reducing weight or increasing physical activity in those at high CVD risk
On Recognizing Transparent Objects in Domestic Environments Using Fusion of Multiple Sensor Modalities
Current object recognition methods fail on object sets that include both
diffuse, reflective and transparent materials, although they are very common in
domestic scenarios. We show that a combination of cues from multiple sensor
modalities, including specular reflectance and unavailable depth information,
allows us to capture a larger subset of household objects by extending a state
of the art object recognition method. This leads to a significant increase in
robustness of recognition over a larger set of commonly used objects.Comment: 12 page
Encoding of low-quality DNA profiles as genotype probability matrices for improved profile comparisons, relatedness evaluation and database searches
Many DNA profiles recovered from crime scene samples are of a quality that does not allow them to be searched against, nor entered into, databases. We propose a method for the comparison of profiles arising from two DNA samples, one or both of which can have multiple donors and be affected by low DNA template or degraded DNA. We compute likelihood ratios to evaluate the hypothesis that the two samples have a common DNA donor, and hypotheses specifying the relatedness of two donors. Our method uses a probability distribution for the genotype of the donor of interest in each sample. This distribution can be obtained from a statistical model, or we can exploit the ability of trained human experts to assess genotype probabilities, thus extracting much information that would be discarded by standard interpretation rules. Our method is compatible with established methods in simple settings, but is more widely applicable and can make better use of information than many current methods for the analysis of mixed-source, low-template DNA profiles. It can accommodate uncertainty arising from relatedness instead of or in addition to uncertainty arising from noisy genotyping. We describe a computer program GPMDNA, available under an open source license, to calculate LRs using the method presented in this paper
Knowledge of UK Dental Undergraduates and Dentists in Treating Dentine Hypersensitivity
Aim: The purpose of the present questionnaire-based study was to evaluate the knowledge and understanding of UK based dental undergraduates and qualified dentists in treating Dentine Hypersensitivity (DH). Methods: 120 questionnaires were handed out to 4th and 5th year dental students and Staff at the Dental Hospital in London UK as part of a collaborative study with the Faculdade de Odontologia de Bauru, University of Sao Paulo, Brazil. The questionnaire consisted of 22 questions, which included both open and closed questions. Results: 91 questionnaires (75.8% response rate) were returned; of the 91 respondents (38M; 52F, 1 missing value) 53 were dentists (61%) and 34 were dental students (39%) (4 missing values). 37.5% of students indicated that 10% of patients suffered from DH whereas 18.9% of dentists indicated that 25% of patients suffered from DH. Both dentists (22.6%) and 27.5% of students indicated that DH lasted >12 weeks. 18.9% of dentists considered that DH was a serious problem for patients although 32.5% of students were not sure. Dentists (66%) and students (62.5%) indicated that DH had a major impact on the quality of life (QOL) with 51.1% (dentists) and 56.3% (students) indicating that it was moderate in nature. Conclusion: The results of the present pilot study would suggest that in terms of knowledge and understanding of DH (e.g., hydrodynamic theory) both dentists (90.5%) and students (76.9%) were comparable although in the assessment and subsequent management of DH the results indicated that dentists were more confident than the student
Oculomotor involvement in spatial working memory is task-specific
Many everyday tasks, such as remembering where you parked, require the capacity to store and manipulate information about the visual and spatial properties of the world. The ability to represent, remember, and manipulate spatial information is known as visuospatial working memory (VSWM). Despite substantial interest in VSWM the mechanisms responsible for this ability remain debated. One influential idea is that VSWM depends on activity in the eye-movement (oculomotor) system. However, this has proved difficult to test because experimental paradigms that disrupt oculomotor control also interfere with other cognitive systems, such as spatial attention. Here, we present data from a novel paradigm that selectively disrupts activation in the oculomotor system. We show that the inability to make eye-movements is associated with impaired performance on the Corsi Blocks task, but not on Arrow Span, Visual Patterns, Size Estimation or Digit Span tasks. It is argued that the oculomotor system is required to encode and maintain spatial locations indicted by a change in physical salience, but not non-salient spatial locations indicated by the meaning of a symbolic cue. This suggestion offers a way to reconcile the currently conflicting evidence regarding the role of the oculomotor system in spatial working memory
Product recognition in store shelves as a sub-graph isomorphism problem
The arrangement of products in store shelves is carefully planned to maximize
sales and keep customers happy. However, verifying compliance of real shelves
to the ideal layout is a costly task routinely performed by the store
personnel. In this paper, we propose a computer vision pipeline to recognize
products on shelves and verify compliance to the planned layout. We deploy
local invariant features together with a novel formulation of the product
recognition problem as a sub-graph isomorphism between the items appearing in
the given image and the ideal layout. This allows for auto-localizing the given
image within the aisle or store and improving recognition dramatically.Comment: Slightly extended version of the paper accepted at ICIAP 2017. More
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http://vision.disi.unibo.it/index.php?option=com_content&view=article&id=111&catid=7
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