Topic model kernel : an empirical study towards probabilistically reduced features for classification

Probabilistic topic models have become a standard in modern machine learning with wide applications in organizing and summarizing ‘documents’ in high-dimensional data such as images, videos, texts, gene expression data, and so on. Representing data by dimensional reduction of mixture proportion extracted from topic models is not only richer in semantics than bag-of-word interpretation, but also more informative for classification tasks. This paper describes the Topic Model Kernel (TMK), a high dimensional mapping for Support Vector Machine classification of data generated from probabilistic topic models. The applicability of our proposed kernel is demonstrated in several classification tasks from real world datasets. We outperform existing kernels on the distributional features and give the comparative results on non-probabilistic data types.

Does reduced mobility through fragmented landscapes explain patch extinction patterns for three honeyeaters?

1.Habitat loss and associated fragmentation are major drivers of biodiversity decline, and understanding how they affect population processes (e.g. dispersal) is an important conservation goal. In a large-scale test employing 10 × 10 km units of replication, three species of Australian birds, the fuscous honeyeater, yellow-tufted honeyeater and white-plumed honeyeater, responded differently to fragmentation. The fuscous and yellow-tufted honeyeaters are ‘decliners’ that disappeared from suitable habitat in landscapes where levels of tree-cover fell below critical thresholds of 17 and 8%, respectively. The white-plumed honeyeater is a ‘tolerant’ species whose likelihood of occurrence in suitable habitat was independent of landscape-level tree-cover. 2.To determine whether the absence of the two decliner species in low tree-cover landscapes can be explained by reduced genetic connectivity, we looked for signatures of reduced mobility and gene flow in response to fragmentation across agricultural landscapes in the Box-Ironbark region of north-central Victoria, Australia. 3.We compared patterns of genetic diversity and population structure at the regional scale and across twelve 100 km2 landscapes with different tree-cover extents. We used genetic data to test landscape models predicting reduced dispersal through the agricultural matrix. We tested for evidence of sex-biased dispersal and sex-specific responses to fragmentation. 4.Reduced connectivity may have contributed to the disappearance of the yellow-tufted honey-eater from low tree-cover landscapes, as evidenced by male bias and increased relatedness among males in low tree-cover landscapes and signals of reduced gene flow and mobility through the agricultural matrix. We found no evidence for negative effects of fragmentation on gene flow in the other decliner, the fuscous honeyeater, suggesting that undetected pressures act on this species. As expected, there was no evidence for decreased movement through fragmented landscapes for the tolerant white-plumed honeyeater. 5.We demonstrated effects of habitat loss and fragmentation (stronger patterns of genetic differentiation, increased relatedness among males) on the yellow-tufted honeyeater above the threshold at which probability of occurrence dropped. Increasing extent and structural connectivity of habitat should be an appropriate management action for this species and other relatively sedentary woodland specialist species for which it can be taken as representative.

Review of transformerless inverter topologies

In the recent years, there has been a widespread trend in the use of the transformerless inverters in the single-phase grid-connected photovoltaic systems. This has been motivated by the low price, minor size, light mass, and great efficiency associated with them. However, when no transformer is used, common-mode voltage appears and leads to ground leakage current through the Photovoltaic parasitic capacitance to the ground due to the non-galvanic isolation configuration. This has lead to a main research focus on ways of minimizing or eliminating these leakage currents without influencing the efficiency of the system. Different topologies have been suggested to eliminate the leakage current in the transformerless grid-connected photovoltaic (PV) systems. In this paper, a review of these transformerless topologies is carried out, in regard to the leakage current for single phase. The benefits, in regard to each scheme, are outlined and their disadvantages explained.

Simulation and evaluation of HERIC and H5 transformerless inverter topologies

Most of the inverters have an isolation transformer which prevents or limits fault current between AC and DC circuits under most fault conditions. If the transformer is excluded from the system, it would increase the PV system efficiency and decrease the size of its installations, which will lead to a lower cost for the whole investment. Thus, elimination of the transformer has to be considered carefully because a galvanic connection appears between the PV arrays and the ground in the absence of an isolation transformer. The galvanic connection causes the stray capacitance between the PV arrays structure and the ground to produce a leakage current. In this paper, a review of full bridge topology with bipolar and unipolar scheme and half bridge topology carried out in regard leakage current.in addition, HERIC and H5 topologies are simulated and leakage current in these topologies are evaluated.

Improved efficacy and reduced toxicity of doxorubicin encapsulated in sulfatide-containing nanoliposome in a glioma model

As a glycosphingolipid that can bind to several extracellular matrix proteins, sulfatide has the potential to become an effective targeting agent for tumors overexpressing tenasin-C in their microenvironment. To overcome the dose-limiting toxicity of doxorubicin (DOX), a sulfatide-containing nanoliposome (SCN) encapsulation approach was employed to improve treatment efficacy and reduce side effects of free DOX. This study analysed in vitro characteristics of sulfatidecontaining nanoliposomal DOX (SCN-DOX) and assessed its cytotoxicity in vitro, as well as biodistribution, therapeutic efficacy, and systemic toxicity in a human glioblastoma U-118MG xenograft model. SCN-DOX was shown to achieve highest drug to lipid ratio (0.5:1) and a remarkable in vitro stability. Moreover, DOX encapsulated in SCN was shown to be delivered into the nuclei and displayed prolonged retention over free DOX in U-118MG cells. This simple two-lipid SCN- DOX nanodrug has favourable pharmacokinetic attributes in terms of prolonged circulation time, reduced volume of distribution and enhanced bioavailability in healthy rats. As a result of the improved biodistribution, an enhanced treatment efficacy of SCNDOX was found in glioma-bearing mice compared to the free drug. Finally, a reduction in the accumulation of DOX in the drug’s principal toxicity organs achieved by SCN-DOX led to the diminished systemic toxicity as evident from the plasma biochemical analyses. Thus, SCN has the potential to be an effective and safer nano-carrier for targeted delivery of therapeutic agents to tumors with elevated expression of tenascin-C in their microenvironment.

Foveal contrast processing of increment and decrement targets is equivalently reduced in glaucoma

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Intramuscular heat shock protein 72 and heme oxygenase-1 mRNA are reduced in patients with type 2 diabetes: evidence that insulin resistance is associated with a disturbed antioxidant defense mechanism

To examine whether genes associated with cellular defense against oxidative stress are associated with insulin sensitivity, patients with type 2 diabetes (n = 7) and age-matched (n = 5) and young (n = 9) control subjects underwent a euglycemic-hyperinsulinemic clamp for 120 min. Muscle samples were obtained before and after the clamp and analyzed for heat shock protein (HSP)72 and heme oxygenase (HO)-1 mRNA, intramuscular triglyceride content, and the maximal activities of β-hyroxyacyl-CoA dehydrogenase (β-HAD) and citrate synthase (CS). Basal expression of both HSP72 and HO-1 mRNA were lower (P < 0.05) by 33 and 55%, respectively, when comparing diabetic patients with age-matched and young control subjects, with no differences between the latter groups. Both basal HSP72 (r = 0.75, P < 0.001) and HO-1 (r = 0.50, P < 0.05) mRNA expression correlated with the glucose infusion rate during the clamp. Significant correlations were also observed between HSP72 mRNA and both β-HAD (r = 0.61, P < 0.01) and CS (r = 0.65, P < 0.01). HSP72 mRNA was induced (P < 0.05) by the clamp in all groups. Although HO-1 mRNA was unaffected by the clamp in both the young and age-matched control subjects, it was increased (P < 0.05) ∼70-fold in the diabetic patients after the clamp. These data demonstrate that genes involved in providing cellular protection against oxidative stress are defective in patients with type 2 diabetes and correlate with insulin-stimulated glucose disposal and markers of muscle oxidative capacity. The data provide new evidence that the pathogenesis of type 2 diabetes involves perturbations to the antioxidant defense mechanism within skeletal muscle.

Values, attitudes, and frequency of meat consumption: predicting meat-reduced diet in Australians

Reduced consumption of meat, particularly red meat, is associated with numerous health benefits. While past research has examined demographic and cognitive correlates of meat-related diet identity and meat consumption behavior, the predictive influence of personal values on meat-consumption attitudes and behaviour, as well as gender differences therein, has not been explicitly examined, nor has past research focusing on 'meat' generally addressed 'white meat' and 'fish/seafood' as distinct categories of interest. Two hundred and two Australians (59.9% female, 39.1% male, 1% unknown), aged 18 to 91 years (M = 31.42, SD = 16.18), completed an online questionnaire including the Schwartz Values Survey, and measures of diet identity, attitude towards reduced consumption of each of red meat, white meat, and fish/seafood, as well as self-reported estimates of frequency of consumption of each meat type. Results showed that higher valuing of Universalism predicted more positive attitudes towards reducing, and less frequent consumption of, each of red meat, white meat, and fish/seafood, while higher Power predicted less positive attitudes towards reducing, and more frequent consumption of, these meats. Higher Security predicted less positive attitudes towards reducing, and more frequent consumption, of white meat and fish/seafood, while Conformity produced this latter effect for fish/seafood only. Despite men valuing Power more highly than women, women valuing Universalism more highly than men, and men eating red meat more frequently than women, gender was not a significant moderator of the value-attitude-behavior mediations described, suggesting that gender's effects on meat consumption may not be robust once entered into a multivariate model of MRD attitudes and behaviour. Results support past findings associating Universalism, Power, and Security values with meat-eating preferences, and extend these findings by articulating how these values relate specifically to different types of meat.