Quantum heat engines: limit cycles and exceptional points

We show that the inability of a quantum Otto cycle to reach a limit cycle is connected with the propagator of the cycle being non-compact. For a working fluid consisting of quantum harmonic oscillators, the transition point in parameter space where this instability occurs is associated with a non-hermitian degeneracy (exceptional point) of the eigenvalues of the propagator. In particular, a third-order exceptional point is observed at the transition from the region where the eigenvalues are complex numbers to the region where all the eigenvalues are real. Within this region we find another exceptional point, this time of second order, at which the trajectory becomes divergent. The onset of the divergent behavior corresponds to the modulus of one of the eigenvalues becoming larger than one. The physical origin of this phenomenon is that the hot and cold heat baths are unable to dissipate the frictional internal heat generated in the adiabatic strokes of the cycle. This behavior is contrasted with that of quantum spins as working fluid which have a compact Hamiltonian and thus no exceptional points. All arguments are rigorously proved in terms of the systems' associated Lie algebras

School Milk Consumption in Germany - What are Important Product Attributes for Children and Parents?

Food Consumption/Nutrition/Food Safety,

School milk demand in Germany: The role of individual and contextual factors - preliminary results

Replaced with revised version of paper 12/01/11.Demand and Price Analysis,

A máj VII-es szegmentumában igazolt áttéti daganat laparoszkópos reszekciója

Absztrakt A májsebészet technikája és eredményei folyamatosan fejlődnek az utóbbi években, amely fejlődés talán legintenzívebben a laparoszkópos májsebészet területén érezhető. Az eddig közölt összehasonlító vizsgálatok alapján a laparoszkópos műtétek eredményei nem maradnak el a nyílt műtétek eredményeitől. Bár a májreszekciók igen kis százalékát végzik laparoszkóposan, a minimálisan invazív reszekciós technikának egyértelműen helye van az onkológiai sebészet területén. A minor, a major, az anatómiai vagy éppen a többszakaszos májreszekciók is elvégezhetők laparoszkóposan, és a korábban általános ajánlás, amely szerint az elöl fekvő szegmentumokban javasolható a minimálisan invazív technika, jelenleg már túlhaladott. A szerzők egy 70 éves nőbeteg esetét mutatják be, akinél rectumdaganat komplex onkosebészeti kezelését követően a máj VII-es szegmentumában kialakult metasztázis miatt végeztek laparoszkópos májreszekciót. Az esetismertetéssel a szerzők arra kívánnak rávilágítani, hogy a hátsó szegmentumok malignus elváltozásai is biztonsággal megközelíthetők és eltávolíthatók laparoszkóppal. Orv. Hetil., 2016, 157(20), 796–800

Urinary levels of free 2,5-hexanedione in Italian subjects non-occupationally exposed to n-hexane

The purpose of the study is to evaluate the urinary levels of free 2,5-hexanedione (2,5-HD) in Italian subjects non-occupationally exposed to n-hexane, in order to define background values in non-occupational settings. The study was carried out on 99 subjects of the general population. The analysis of free 2,5-HD was performed by gas chromatography-mass spectrometry. Personal information about the subjects was ascertained by means of a self-administered questionnaire. The urinary levels of free 2,5-HD were in the range of <12.0\u201377.9 g/L (5th\u201395th percentiles). The urinary excretion of the metabolite did not seem to be influenced by gender, age, smoking habit or area of residence. Statistically significant dierences (p = 0.03) were found between the free 2,5-HD urinary levels according to the vehicular trac intensity within the area of residence and to body mass index of subjects. The background levels of free 2,5-HD found in this study could contribute to the definition of reference values of general population non-occupationally exposed and could be useful to the toxicologists and industrial hygienists to determine whether workers have been exposed to higher levels of n-hexane than the general population

APEnet+: a 3D toroidal network enabling Petaflops scale Lattice QCD simulations on commodity clusters

Many scientific computations need multi-node parallelism for matching up both space (memory) and time (speed) ever-increasing requirements. The use of GPUs as accelerators introduces yet another level of complexity for the programmer and may potentially result in large overheads due to the complex memory hierarchy. Additionally, top-notch problems may easily employ more than a Petaflops of sustained computing power, requiring thousands of GPUs orchestrated with some parallel programming model. Here we describe APEnet+, the new generation of our interconnect, which scales up to tens of thousands of nodes with linear cost, thus improving the price/performance ratio on large clusters. The project target is the development of the Apelink+ host adapter featuring a low latency, high bandwidth direct network, state-of-the-art wire speeds on the links and a PCIe X8 gen2 host interface. It features hardware support for the RDMA programming model and experimental acceleration of GPU networking. A Linux kernel driver, a set of low-level RDMA APIs and an OpenMPI library driver are available, allowing for painless porting of standard applications. Finally, we give an insight of future work and intended developments

Language-Guided Audio-Visual Source Separation via Trimodal Consistency

We propose a self-supervised approach for learning to perform audio source separation in videos based on natural language queries, using only unlabeled video and audio pairs as training data. A key challenge in this task is learning to associate the linguistic description of a sound-emitting object to its visual features and the corresponding components of the audio waveform, all without access to annotations during training. To overcome this challenge, we adapt off-the-shelf vision-language foundation models to provide pseudo-target supervision via two novel loss functions and encourage a stronger alignment between the audio, visual and natural language modalities. During inference, our approach can separate sounds given text, video and audio input, or given text and audio input alone. We demonstrate the effectiveness of our self-supervised approach on three audio-visual separation datasets, including MUSIC, SOLOS and AudioSet, where we outperform state-of-the-art strongly supervised approaches despite not using object detectors or text labels during training.Comment: Accepted at CVPR 202

Gratitude, resignation and the desire for dignity: lived experience of food charity recipients and their recommendations for improvement, Perth, Western Australia

ObjectiveThe present study explored recipients’ perceptions of food charity and their suggested improvements in inner-city Perth, Western Australia.DesignIn-depth interviews were conducted with charitable food service (CFS) recipients. Transcripts were thematically analysed using a phenomenological approach.SettingInterviews were conducted at two CFS in inner-city Perth.SubjectsFourteen adults.ResultsThe recipients’ journeys to a reliance on CFS were varied and multifactorial, with poverty, medical issues and homelessness common. The length of time recipients had relied on food charity ranged from 8 months to over 40 years. Most were ‘grateful yet resigned’, appreciative of any food and resigned to the poor quality, monotony and their unmet individual preferences. They wanted healthier food, more variety and better quality. Accessing services was described as a ‘full-time job’ fraught with unreliable information and transport difficulties. They called for improved information and assistance with transport. ‘Eroded dignity’ resulted from being fed without any choice and queuing for food in public places, often in a volatile environment. ‘Food memories and inclusion’ reflected a desire for commensality. Recipients suggested services offer choice and promote independence, focusing on their needs both physical and social.ConclusionsAlthough grateful, long-term CFS recipients described what constitutes a voluntary failure. Their service improvement recommendations can help meet their nutritional and social needs. A successful CFS provides a food service that prioritises nutritious, good-quality food and individual need, while promoting dignity and social inclusion, challenging in the current Australian context

Genetic Characterization of Cancer of Unknown Primary Using Liquid Biopsy Approaches

Cancers of unknown primary (CUPs) comprise a heterogeneous group of rare metastatic tumors whose primary site cannot be identified after extensive clinical–pathological investigations. CUP patients are generally treated with empirical chemotherapy and have dismal prognosis. As recently reported, CUP genome presents potentially druggable alterations for which targeted therapies could be proposed. The paucity of tumor tissue, as well as the difficult DNA testing and the lack of dedicated panels for target gene sequencing are further relevant limitations. Here, we propose that circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) could be used to identify actionable mutations in CUP patients. Blood was longitudinally collected from two CUP patients. CTCs were isolated with CELLSEARCH® and DEPArrayTM NxT and Parsortix systems, immunophenotypically characterized and used for single-cell genomic characterization with Ampli1TM kits. Circulating cell-free DNA (ccfDNA), purified from plasma at different time points, was tested for tumor mutations with a CUP-dedicated, 92-gene custom panel using SureSelect Target Enrichment technology. In parallel, FFPE tumor tissue was analyzed with three different assays: FoundationOne CDx assay, DEPArray LibPrep and OncoSeek Panel, and the SureSelect custom panel. These approaches identified the same mutations, when the gene was covered by the panel, with the exception of an insertion in APC gene. which was detected by OncoSeek and SureSelect panels but not FoundationOne. FGFR2 and CCNE1 gene amplifications were detected in single CTCs, tumor tissue, and ccfDNAs in one patient. A somatic variant in ARID1A gene (p.R1276∗) was detected in the tumor tissue and ccfDNAs. The alterations were validated by Droplet Digital PCR in all ccfDNA samples collected during tumor evolution. CTCs from a second patient presented a pattern of recurrent amplifications in ASPM and SEPT9 genes and loss of FANCC. The 92-gene custom panel identified 16 non-synonymous somatic alterations in ccfDNA, including a deletion (I1485Rfs∗19) and a somatic mutation (p. A1487V) in ARID1A gene and a point mutation in FGFR2 gene (p.G384R). Our results support the feasibility of non-invasive liquid biopsy testing in CUP cases, either using ctDNA or CTCs, to identify CUP genetic alterations with broad NGS panels covering the most frequently mutated genes