Quantum steering ellipsoids, extremal physical states and monogamy

A Corrigendum for this article has been published in 2015 New J. Phys. 17 019501Any two-qubit state can be faithfully represented by a steering ellipsoid inside the Bloch sphere, but not every ellipsoid inside the Bloch sphere corresponds to a two-qubit state. We give necessary and sufficient conditions for when the geometric data describe a physical state and investigate maximal volume ellipsoids lying on the physical-unphysical boundary. We derive monogamy relations for steering that are strictly stronger than the Coffman-Kundu- Wootters (CKW) inequality for monogamy of concurrence. The CKW result is thus found to follow from the simple perspective of steering ellipsoid geometry. Remarkably, we can also use steering ellipsoids to derive non-trivial results in classical Euclidean geometry, extending Eulers inequality for the circumradius and inradius of a triangle.The EPSRC and the ARC Centre of Excellence grant no. CE110001027. DJ is funded by the Royal Society. TR would like to thank the Leverhulme Trust. SJ acknowledges EPSRC grant EP/ K022512/1

Quality of Honey Bee Bread Collected in Spring

Pollen is the only source of protein that honey bees collect from nature. It is very important for the development of brood, and consequently, for the development of the colony. Honey bee bread is the pollen which the bees collect from flowers and store in honeycomb cells. Honey bee bread has a modified structure due to the fermentation process under the influence of enzymes it passes through. For this study, ten honey bee colonies were selected. Honey bee bread was sampled from the combs. The quality of pollen and honey bee bread was determined by the chemical composition, using standard methods used in food analysis. Total nitrogen was determined by Kjeldahl method. Micro- and macroelements were determined by spectrophotometric method. The pollen collected from two sites had rich protein content (29.93 % and 27.63 % on average)

The Effect of Hive Volume on Efficiency and Strength Conservation and Restoration of Food Supplies During the Wintering in Langstroth Hives

The influence of volume of the hive on wintering, colony strength and food supply was observed during the three-year period. Standard LR hives were used for the experiment. Colonies were tested based on the number of hive bodies and the number of frames in the brood hive bodies. The colonies were divided into two groups based on the number of frames: group I had eight frames in the brood bodies, the second group included 10 frames in the brood bodies. Based on the number of hive bodies, colonies were also divided into two groups: colonies with a single hive body and colonies with two hive bodies. The inspections were carried out in the autumn in late August and early September, and in the spring in late March and early April. Colony strength was determined by the amount of brood and food supplies through the amount of honey and pollen. It was found that the number of frames in the brood bodies had almost no impact on the colony strength and the amount of food in the autumn and spring inspections. Percentage ratio in spring and autumn inspections was more favourable in ten-frame hives considering the amount of bees and pollen. The ratio for the amount of brood between the two inspections was higher in eight-frame hives. The colonies replenished bees more rapidly and foraged pollen more efficiently in ten-frame hives while the colonies in eight-frame hives replenished brood quicker. It was found that, during the three-year period, the hive volume had impact on strength and food supply of colonies. Colonies that have wintered in two hive bodies had favourable ratio of spring and autumn inspections for the amount of bees, brood and pollen, while the ratio for the amount of honey was more favourable in the colonies with a single hive body. The colonies with two hive bodies quicker restored strength and pollen supply, while the colonies with a single hive body consumed honey supply more rationally

Insecticidal Activity of Sage (Salvia Officinalis) Essential Oil to Varroa Destructor (Acari: Varroidae) and Apis Mellifera (Hymenoptera: Apidae)

The need to find alternative systems of the fight against Varroa mite without application of chemicals and provide healthy bee products resulted in investigation of application of different plant essences to arthropod control. In order to perceive the sage essential oil (Salvia officinalis) bioactivity, contact residual toxicity of mites and bees was examined in the laboratory conditions. The chemical composition of essential oil was determined by standard GC and GC/MS methods. Different doses of the sage essential oil dissolved in acetone (0.1–10 μl/Petri dish) were applied in Petri dishes and left to dry for 20 minute at a room temperature. Following this period of time, ten honey bees and five adult female mites were added in each Petri dish and they were all maintained in controlled conditions (T = 30°C, Relative humidity = 60%). Survival of examined honey bees and Varroa mites was recorded two times, after 24 h and 48 h. The most prominent toxic effect on the examined Varroa mites was observed after 24 h and 48 h, with application of 10 μl of sage oil (the average values for dead mite individuals were 3.25 and 3.50, respectively). Recorded biological activities of the oil tested in different doses on both honey bee and Varroa mite revealed opportunity to proceed with further investigation by selecting the most appropriate variants and combinations of the most prominent individual components of the examined sage oil

A measure of majorisation emerging from single-shot statistical mechanics

The use of the von Neumann entropy in formulating the laws of thermodynamics has recently been challenged. It is associated with the average work whereas the work guaranteed to be extracted in any single run of an experiment is the more interesting quantity in general. We show that an expression that quantifies majorisation determines the optimal guaranteed work. We argue it should therefore be the central quantity of statistical mechanics, rather than the von Neumann entropy. In the limit of many identical and independent subsystems (asymptotic i.i.d) the von Neumann entropy expressions are recovered but in the non-equilbrium regime the optimal guaranteed work can be radically different to the optimal average. Moreover our measure of majorisation governs which evolutions can be realized via thermal interactions, whereas the nondecrease of the von Neumann entropy is not sufficiently restrictive. Our results are inspired by single-shot information theory.Comment: 54 pages (15+39), 9 figures. Changed title / changed presentation, same main results / added minor result on pure bipartite state entanglement (appendix G) / near to published versio

Improvement for detection of microcalcifications through clustering algorithms and artificial neural networks

A new method for detecting microcalcifications in regions of interest (ROIs) extracted from digitized mammograms is proposed. The top-hat transform is a technique based on mathematical morphology operations and, in this paper, is used to perform contrast enhancement of the mi-crocalcifications. To improve microcalcification detection, a novel image sub-segmentation approach based on the possibilistic fuzzy c-means algorithm is used. From the original ROIs, window-based features, such as the mean and standard deviation, were extracted; these features were used as an input vector in a classifier. The classifier is based on an artificial neural network to identify patterns belonging to microcalcifications and healthy tissue. Our results show that the proposed method is a good alternative for automatically detecting microcalcifications, because this stage is an important part of early breast cancer detectio

The HEV Ventilator

HEV is a low-cost, versatile, high-quality ventilator, which has been designed in response to the COVID-19 pandemic. The ventilator is intended to be used both in and out of hospital intensive care units, and for both invasive and non-invasive ventilation. The hardware can be complemented with an external turbine for use in regions where compressed air supplies are not reliably available. The standard modes provided include PC-A/C(Pressure Assist Control),PC-A/C-PRVC(Pressure Regulated Volume Control), PC-PSV (Pressure Support Ventilation) and CPAP (Continuous Positive airway pressure). HEV is designed to support remote training and post market surveillance via a web interface and data logging to complement the standard touch screen operation, making it suitable for a wide range of geographical deployment. The HEV design places emphasis on the quality of the pressure curves and the reactivity of the trigger, delivering a global performance which will be applicable to ventilator needs beyond theCOVID-19 pandemic. This article describes the conceptual design and presents the prototype units together with their performance evaluation.Comment: 34 pages, 18 figures, Extended version of the article submitted to PNA

Spinal infection: state of the art and management algorithm

Spinal infection is a rare pathology although a concerning rising incidence has been observed in recent years. This increase might reflect a progressively more susceptible population but also the availability of increased diagnostic accuracy. Yet, even with improved diagnosis tools and procedures, the delay in diagnosis remains an important issue. This review aims to highlight the importance of a methodological attitude towards accurate and prompt diagnosis using an algorithm to aid on spinal infection management. METHODS: Appropriate literature on spinal infection was selected using databases from the US National Library of Medicine and the National Institutes of Health. RESULTS: Literature reveals that histopathological analysis of infected tissues is a paramount for diagnosis and must be performed routinely. Antibiotic therapy is transversal to both conservative and surgical approaches and must be initiated after etiological diagnosis. Indications for surgical treatment include neurological deficits or sepsis, spine instability and/or deformity, presence of epidural abscess and upon failure of conservative treatment. CONCLUSIONS: A methodological assessment could lead to diagnosis effectiveness of spinal infection. Towards this, we present a management algorithm based on literature findings

Observation of the Decay Λ0b→Λ+cτ−¯ν

The first observation of the semileptonic b-baryon decay Λb0→Λc+τ-ν¯τ, with a significance of 6.1σ, is reported using a data sample corresponding to 3 fb-1 of integrated luminosity, collected by the LHCb experiment at center-of-mass energies of 7 and 8 TeV at the LHC. The τ- lepton is reconstructed in the hadronic decay to three charged pions. The ratio K=B(Λb0→Λc+τ-ν¯τ)/B(Λb0→Λc+π-π+π-) is measured to be 2.46±0.27±0.40, where the first uncertainty is statistical and the second systematic. The branching fraction B(Λb0→Λc+τ-ν¯τ)=(1.50±0.16±0.25±0.23)% is obtained, where the third uncertainty is from the external branching fraction of the normalization channel Λb0→Λc+π-π+π-. The ratio of semileptonic branching fractions R(Λc+)B(Λb0→Λc+τ-ν¯τ)/B(Λb0→Λc+μ-ν¯μ) is derived to be 0.242±0.026±0.040±0.059, where the external branching fraction uncertainty from the channel Λb0→Λc+μ-ν¯μ contributes to the last term. This result is in agreement with the standard model prediction