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A test for the global minimum variance portfolio for small sample and singular covariance

Recently, a test dealing with the linear hypothesis for the global minimum variance portfolio weights was obtained under the assumption of non-singular covariance matrix. However, the problem of potential multicollinearity and correlations of assets constitutes a limitation of the classical portfolio theory. Therefore, there is an interest in developing theory in the presence of singularities in t

Anaerobic poly-3-d-hydroxybutyrate production from xylose in recombinant Saccharomyces cerevisiae using a NADH-dependent acetoacetyl-CoA reductase

Background: Poly-3-d-hydroxybutyrate (PHB) that is a promising precursor for bioplastic with similar physical properties as polypropylene, is naturally produced by several bacterial species. The bacterial pathway is comprised of the three enzymes β-ketothiolase, acetoacetyl-CoA reductase (AAR) and PHB synthase, which all together convert acetyl-CoA into PHB. Heterologous expression of the pathway

Ionic Liquid Ordering at an Oxide Surface

The interaction of the ionic liquid [C4C1Im][BF4] with anatase TiO2, a model photoanode material, has been studied using a combination of synchrotron radiation photoelectron spectroscopy and near-edge X-ray absorption fine structure spectroscopy. The system is of interest as a model for fundamental electrolyte–electrode and dye-sensitized solar cells. The initial interaction involves degradation o

A typology of political participation online : How citizens used Twitter to mobilize during the 2015 British general elections

This study investigates how, and to what extent, citizens use Twitter as a platform for political mobilization in an electoral context. Conceptualizing political participation as a process, we develop a typology of political participation designed to isolate mobilizing calls for action from the rest of the political discussion online. Based on Twitter data collected one week prior to the 2015 Brit

Land-atmosphere feedbacks amplify aridity increase over land under global warming

The response of the terrestrial water cycle to global warming is central to issues including water resources, agriculture and ecosystem health. Recent studies indicate that aridity, defined in terms of atmospheric supply (precipitation, P) and demand (potential evapotranspiration, E p) of water at the land surface, will increase globally in a warmer world. Recently proposed mechanisms for this res

Multiple Forms of Endocannabinoid and Endovanilloid Signaling Regulate the Tonic Control of GABA Release

UNLABELLED: Persistent CB1 cannabinoid receptor activity limits neurotransmitter release at various synapses throughout the brain. However, it is not fully understood how constitutively active CB1 receptors, tonic endocannabinoid signaling, and its regulation by multiple serine hydrolases contribute to the synapse-specific calibration of neurotransmitter release probability. To address this questi

To distribute or not to distribute? Impact of latency on Virtual Network Function distribution at the edge of FMC networks

The Network Function Virtualization paradigm enables the possibility to dynamically instantiate Virtual Network Functions (VNFs) in Commercial-Off-The-Shelf (COTS) hardware. Such VNFs are then concatenated together in Service Chains (SCs) to provide specific Internet services to the users. Depending on latency requirements for such services and considering the aim of maximally consolidating the VN

Flame stabilization and emission characteristics of a prototype gas turbine burner at atmospheric conditions

In the present work, a downscaled prototype 4th generation Dry Low Emission gas turbine (SGT-750) burner (designed and manufactured by Siemens Industrial Turbomachinery AB, Sweden) was investigated using an atmospheric experimental facility. The primary purpose of the research is to analyze flame stability and emission capability of the burner. OH Planar Laser-Induced Fluorescence (OH-PLIF), and c

The Perfect Storm: Sovereignty Games and the Law and Politics of Boat Migration

4.690 migrants have lost their lives in the Mediterranean this year, making 2016 once again set a tragic record and the Mediterranean account for more than three fourths of all registered migrant casualties worldwide. In his most recent book chapter, “The Perfect Storm: Sovereignty Games and the Law and Politics of Boat Migration”, Research Director and Professor Thomas Gammeltoft-Hansen argues th

Collagen of the extracellular matrix. Functional and structural studies.

The cancer microenvironment has been attracting increasing attention as the realization of its importance for both disease treatment and malignant progression. Here the aim was to elucidate some of the effects and mechanisms of the tumor microenvironment related to the extracellular matrix (ECM). We hypothesized that collagen fibril assembly is an instrumental component in the formation of the bar

Digitalization and Privacy : A systematic literature review

The research area of Digitalization and Privacy, as defined and delimited within the context of this knowledge review, (mainly through the selection of search strings), is in a phase of development. The present study has been delimited to articles in English that have been published in scientific peer-reviewed journals. During the past ten years, the number of scientific articles per year has incr

Understanding Poverty : Seeking Synergies Between the Three Discourses of Development, Gender, and Environment

Policies and strategies to fight global environmental degradation, gender inequality, and poverty are often inadequate, ineffective, or insufficient. In response, this article seeks potential synergies and leverage points between three significant interrelated discourses that are often treated separately—development, gender, and environment. Proceeding from a brief history of development thinking

Enclosures in West Pokot, Kenya : Transforming land, livestock and livelihoods in drylands

Dryland livestock production systems are changing in many parts of the world, as a result of growing human populations and associated pressure on water and land. Based on a combination of social and natural science methods, we studied a 30-year transformation process from pastoralism to a livestock-based agro-pastoral system in northwestern Kenya, with the overall aim to increase the understanding

Bioenergy and Land Use Change-State of the Art

The dedicated production of biomass crops and the collection of residues in agriculture and forestry can lead to undesirable negative impacts and it is crucial that practices are found that ensure that these impacts are avoided or mitigated as far as possible. This chapter concerns the use of biomass for energy and the connection between increased bioenergy use and land use change (LUC). Land use

CD8αβ+ γδ T cells : A novel T cell subset with a potential role in inflammatory bowel disease

γδ T cells have been attributed a wide variety of functions, which in some cases may appear as contradictory. To better understand the enigmatic biology of γδ T cells it is crucial to define the constituting subpopulations. γδ T cells have previously been categorized into two subpopulations: CD8aa+ and CD8- cells. In this study we have defined and characterized a novel subset of human γδ T-cells e

Panel stationary tests against changes in persistence

In this paper we propose new panel tests to detect changes in persistence. The test statistics are used to test the null hypothesis of stationarity against the alternative of a change in persistence from I(0) to I(1), from I(1) to I(0), and in an unknown direction. The limiting null distributions of the tests are derived and evaluated in small samples by means of Monte Carlo simulations. An empiri

Blood pressure treatment levels and choice of antihypertensive agent in people with diabetes mellitus : an overview of systematic reviews

OBJECTIVE:: Multiple systematic reviews address the effect of antihypertensive treatment in people with diabetes. Here, we summarize current systematic reviews concerning antihypertensive treatment effect at different blood pressure (BP) levels, and relative treatment effect of different antihypertensive agents. METHODS:: We searched MEDLINE, BIOSIS, DARE and CDSR during years 2005–2016. Eligibili

Effects of wastewater treatment plant effluent inputs on planktonic metabolic rates and microbial community composition in the Baltic Sea

The Baltic Sea is the world's largest area suffering from eutrophication-driven hypoxia. Low oxygen levels are threatening its biodiversity and ecosystem functioning. The main causes for eutrophication-driven hypoxia are high nutrient loadings and global warming. Wastewater treatment plants (WWTP) contribute to eutrophication as they are important sources of nitrogen to coastal areas. Here, we eva