Comparison of Krylov subspace methods with preconditioning techniques for solving boundary value problems

AbstractIn this paper, we made an attempt to establish the usefulness of Lanczos solver with preconditioning technique over the preconditioned Conjugate Gradient (CG) solvers. We have presented here a detail comparative study with respect to convergence, speed as well as CPU-time, by considering appropriate boundary value problems

Queen success is correlated with worker-brood genetic relatedness in a primitively eusocial wasp (Ropalidia marginata)

Ropalidia marginata is a primitively eusocial polistine wasp in which, although there is only one queen at any given time, frequent queen replacements lead to a system of serial polygyny. One of the most striking features of this system is the enormous variation in the success of different queens. Measuring queen success as queen tenure, total number of offspring produced, number of offspring produced per day of tenure, and proportion of eggs laid that develop into adults, we show here that each measure of queen success is correlated with worker-brood genetic relatedness and not correlated with worker:brood ratio or the age of the queen at takeover. We interpret these results as meaning that queens are better able to obtain the cooperation of workers when worker-brood genetic relatedness is high

A compressive survey on different image processing techniques to identify the brain tumor.

Medical imaging technology has revolutionized health care over the past three decades, allowing doctors to detect, cure and improve patient outcomes. Medicinal imaging involves pictures - of internal organs, parts, tissues and bones - for therapeutic examination and research purposes. X-ray and CT scanners are the two greatest results of progress in imaging methods supplanting 2D procedures. Magnetic resonance imaging (MRI) is an imaging procedure that is utilized in radiology to visualize interior structures of the body and better understand how they work. X-ray provides a 3D image of the body's interior; as well as being critical for tumor discovery, this also enables surgeons to more easily dissect infections or tumors than was possible with older X-beam technology, which provided a 2D image. This paper provides an overview of different systems that can be used for distinguishing and preparing medical images

Mixed germ cell tumour of testis: a case report with review of literature

Testicular tumours are rare neoplasm. Mixed germ cell tumour is the most common histological variant. Essentially, any admixture of the germ cell tumours as seen in pure form may be seen, one of the most common admixtures being embryonal carcinoma and teratoma. Unfortunately many of these patients present late usually with some complications. We present a rare case of mixed germ cell tumour with predominant embryonal carcinoma and yolk sac tumour in adolescent patient with multiple metastatic foci at the time of presentation

PERFORMANCE STUDY OF FLEXIBLE PAVEMENTS ON NON EXPANSIVE SOILS

As part of infrastructure development   huge investment is being made on expansion of National highways and important roads across the country.  For improvement of Highways two types of Pavements are commonly used in India viz., Flexible Pavements (Bituminous) and rigid pavements (Concrete). Flexible pavements are widely used in this country from the considerations of economy The performance of Flexible pavements depends largely on properties of original ground on which the pavement rests, the quality of materials used in the construction of various layers of pavement and quality assurance as per relevant specifications. In general any road after construction is basically evaluated by the performance in terms of unevenness index and structural stability over a period of time. The evaluation of these two important parameters will facilitate the clear understanding of performance of various materials used in the construction and to undertake suitable rehabilitation measures if necessary. Keywords: Expansive Soil, Flexible Pavement

Probing scrambling using statistical correlations between randomized measurements

We propose and analyze a protocol to study quantum information scrambling using statistical correlations between measurements, which are performed after evolving a quantum system from randomized initial states. We prove that the resulting correlations precisely capture the so-called out-of-time-ordered correlators and can be used to probe chaos in strongly-interacting, many-body systems. Our protocol requires neither reversing time evolution nor auxiliary degrees of freedom, and can be realized in state-of-the-art quantum simulation experiments.Comment: This version v2 (8 pages, 7 figures) includes important new results compared to our original submission. (1) We present a protocol and corresponding mathematical proof to access OTOCs with local operations, and which can be realized in quantum simulation experiments with available technology. (2) We illustrate the realization of the protocols with different examples for Hubbard and spin model

The value of ischemia-modified albumin compared with d-dimer in the diagnosis of pulmonary embolism

<p>Abstract</p> <p>Study objective</p> <p>The primary aim of this study was to investigate whether IMA levels are helpful in the diagnosis of pulmonary embolism (PE). The secondary aim was to determine whether IMA was more effective alone or in combination with clinical probability scores in the diagnosis of PE. Thirdly, the sensitivity and specificity of IMA is compared with D-dimer both with and without clinical probability scores in patients with suspected PE.</p> <p>Methods</p> <p>Consecutive patients presenting to the emergency department with suspected PE were prospectively recruited, and healthy volunteers were also enrolled as controls. D-dimer and IMA levels were measured for the entire study group. Wells and Geneva scores were calculated and s-CTPA was performed on all suspected PE patients.</p> <p>Results</p> <p>The study population consisted of 130 patients with suspected PE and 59 healthy controls. Mean IMA levels were 0.362 ± 0.11 ABSU for Group A, the PE group (n = 75); 0.265 ± 0.07 ABSU for Group B, the non-PE group (n = 55); and 0.175 ± 0.05 ABSU for Group C, the healthy control group (p < 0.0001). At a cut-off point of 0.25 ABSU, IMA was 93% sensitive and 75% specific in the diagnosis of PE. PPV was 79.4% and NPV was 78.6%. Mean D-dimer levels were 12.48 ± 10.88 μg/ml for Group A; 5.36 ± 7.80 μg/ml for Group B and 0.36 ± 0.16 μg/ml for Group C (p < 0.0001). The D-dimer cut-off point was 0.81 μg/ml with a sensitivity of 98.9% and a specificity of 62.7%, PPV of 69.4% and NPV of 83.3%. The use of IMA in combination with Wells and Geneva clinical probability scores was determined to have a positive impact on these scores' sensitivity and negative predictive values.</p> <p>Conclusion</p> <p>IMA is a good alternative to D-dimer in PE diagnosis in terms of both cost and efficiency. Used in combination with clinical probability scores, it has a similar positive effect on NPV and sensitivity to that of D-dimer. The PPV of IMA is better than D-dimer, but it is still unable to confirm a diagnosis of PE without additional investigation.</p

Generalization Mediates Sensitivity to Complex Odor Features in the Honeybee

Animals use odors as signals for mate, kin, and food recognition, a strategy which appears ubiquitous and successful despite the high intrinsic variability of naturally-occurring odor quantities. Stimulus generalization, or the ability to decide that two objects, though readily distinguishable, are similar enough to afford the same consequence [1], could help animals adjust to variation in odor signals without losing sensitivity to key inter-stimulus differences. The present study was designed to investigate whether an animal's ability to generalize learned associations to novel odors can be influenced by the nature of the associated outcome. We use a classical conditioning paradigm for studying olfactory learning in honeybees [2] to show that honeybees conditioned on either a fixed- or variable-proportion binary odor mixture generalize learned responses to novel proportions of the same mixture even when inter-odor differences are substantial. We also show that the resulting olfactory generalization gradients depend critically on both the nature of the stimulus-reward paradigm and the intrinsic variability of the conditioned stimulus. The reward dependency we observe must be cognitive rather than perceptual in nature, and we argue that outcome-dependent generalization is necessary for maintaining sensitivity to inter-odor differences in complex olfactory scenes

Bumblebees exhibit the memory spacing effect

Associative learning is key to how bees recognize and return to rewarding floral resources. It thus plays a major role in pollinator floral constancy and plant gene flow. Honeybees are the primary model for pollinator associative learning, but bumblebees play an important ecological role in a wider range of habitats, and their associative learning abilities are less well understood. We assayed learning with the proboscis extension reflex (PER), using a novel method for restraining bees (capsules) designed to improve bumblebee learning. We present the first results demonstrating that bumblebees exhibit the memory spacing effect. They improve their associative learning of odor and nectar reward by exhibiting increased memory acquisition, a component of long-term memory formation, when the time interval between rewarding trials is increased. Bombus impatiens forager memory acquisition (average discrimination index values) improved by 129% and 65% at inter-trial intervals (ITI) of 5 and 3 min, respectively, as compared to an ITI of 1 min. Memory acquisition rate also increased with increasing ITI. Encapsulation significantly increases olfactory memory acquisition. Ten times more foragers exhibited at least one PER response during training in capsules as compared to traditional PER harnesses. Thus, a novel conditioning assay, encapsulation, enabled us to improve bumblebee-learning acquisition and demonstrate that spaced learning results in better memory consolidation. Such spaced learning likely plays a role in forming long-term memories of rewarding floral resources