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Testing slope homogeneity in large panels with serial correlation

Pesaran and Yamagata (Pesaran, M.H., Yamagata, T., Testing slope homogeneity in large panels, Journal of Econometrics 142, 50–93, 2008) propose a test for slope homogeneity in large panels, which has become very popular in the literature. However, the test cannot deal with the practically relevant case of heteroskedastic and/serially correlated errors. The present note proposes a generalized test

An Arctic CCN-limited cloud-aerosol regime

On average, airborne aerosol particles cool the Earth's surface directly by absorbing and scattering sunlight and indirectly by influencing cloud reflectivity, life time, thickness or extent. Here we show that over the central Arctic Ocean, where there is frequently a lack of aerosol particles upon which clouds may form, a small increase in aerosol loading may enhance cloudiness thereby likely cau

Control of self-motion in dynamic fluids: fish do it differently from bees.

To detect and avoid collisions, animals need to perceive and control the distance and the speed with which they are moving relative to obstacles. This is especially challenging for swimming and flying animals that must control movement in a dynamic fluid without reference from physical contact to the ground. Flying animals primarily rely on optic flow to control flight speed and distance to obstac

Treating to target with etanercept in rheumatoid arthritis: cost-effectiveness of dose reductions when remission is achieved.

Current management of rheumatoid arthritis (RA) focuses on inducing remission as early as possible to avoid lasting joint damage, and maintenance of remission has become important. A 12-month clinical trial in 834 patients with moderate RA investigated whether etanercept 50 mg/wk could be reduced to half dose or discontinued in patients who achieved low disease activity after 36 weeks.

Separation of net ecosystem exchange into assimilation and respiration using a light response curve approach: critical issues and global evaluation

The measured net ecosystem exchange (NEE) of CO2 between the ecosystem and the atmosphere reflects the balance between gross CO2 assimilation [gross primary production (GPP)] and ecosystem respiration (R-eco). For understanding the mechanistic responses of ecosystem processes to environmental change it is important to separate these two flux components. Two approaches are conventionally used: (1)

Structural, functional and chemical changes in Pseudozyma antarctica lipase B on exposure to hydrogen peroxide.

The effect on primary, secondary, tertiary and quaternary structure of Pseudozyma (formerly Candida) antarctica lipase B (PalB) on exposure to hydrogen peroxide was investigated using nano-electrospray ionization-mass spectrometry (nano-ESI-MS), liquid chromatography tandem mass spectrometry (LC/MS/MS), circular dichroism (CD), and dynamic light scattering (DLS). Treatment with hydrogen peroxide g

Knowing work - Cultivating a practice-based epistemology of knowledge in organization studies

While knowledge theorists urge attention to knowing in practice, two common habits in the empirical literature, which we call knowledge inherency and skepticism, function to re-center certain practitioners. The sites in which we study knowing thereby remain limited, hindering a fuller practice turn. We argue that this enduring tendency is problematic because it inhibits our understanding of ‘commu

Genetic and Family and Community Environmental Effects on Drug Abuse in Adolescence: A Swedish National Twin and Sibling Study

Objective: Using Swedish nationwide registry data, the authors investigated genetic and environmental risk factors in the etiology of drug abuse by twin sibling modeling. The authors followed up with epidemiological analyses to identify shared environmental influences on drug abuse. Method: Drug abuse was defined using public medical, legal, or pharmacy records. Twin and sibling pairs were obtaine

Doping GaP Core-Shell Nanowire pn-Junctions: A Study by Off-Axis Electron Holography

The doping process in GaP core-shell nanowire pn-junctions using different precursors is evaluated by mapping the nanowires' electrostatic potential distribution by means of off-axis electron holography. Three precursors, triethyltin (TESn), ditertiarybutylselenide, and silane are investigated for n-type doping of nanowire shells; among them, TESn is shown to be the most efficient precursor. Off-a

The effects of acquisition on the growth of new technology-based firms: Do different types of acquirers matter?

The growth of new technology-based firms (NTBFs) is usually restricted by their limited ownership and management structures. This paper explores whether acquisition, particularly that by multinational enterprises (MNEs), promotes the growth of NTBFs. Based on Swedish micro-level longitudinal data, this study further distinguishes between Swedish MNEs and foreign MNEs as acquirers and disentangles

Points to consider for prioritizing clinical genetic testing services: a European consensus process oriented at accountability for reasonableness.

Given the cost constraints of the European health-care systems, criteria are needed to decide which genetic services to fund from the public budgets, if not all can be covered. To ensure that high-priority services are available equitably within and across the European countries, a shared set of prioritization criteria would be desirable. A decision process following the accountability for reasona

Dykes of the 1.11 Ga Umkondo LIP, Southern Africa: Clues to a complex plumbing system

The Umkondo Large Igneous Province (LIP) is represented by widespread (similar to 2.0 x 10(6) km(2)) mafic intrusions that were rapidly emplaced (1112-1108 Ma) into the Kalahari craton of southern Africa and the formerly adjacent Grunehogna Province of Antarctica during Rodinia assembly. Very few Umkondo-aged dykes have been identified before, resulting in a poor understanding of this LIP's plumbi

How Green Marketing Works: Practices, Materialities and Images

There are surprisingly few empirical studies of green marketing practices, and when such studies are carried out, they tend to take a simplistic approach. In this paper, the need to develop more complex and critical analyses of green marketing practices is addressed through the development of a practice theory approach to green marketing. Drawing on an ethnographic study of the Nordic Nature Shop,

The influence of predator regime on the behaviour and mortality of a freshwater amphipod, Gammarus pulex

In species with restricted dispersal, traits may become genetically fixed leading to local adaptations. Therefore, predator avoidance in a prey species may differ between populations experiencing different predator regimes, but also between sexes within a population due to different vulnerability to predators. In this study we used male and female Gammarus pulex from two different predator regimes

Eltoprazine counteracts l-DOPA-induced dyskinesias in Parkinson's disease: a dose-finding study.

In advanced stages of Parkinson's disease, serotonergic terminals take up l-DOPA and convert it to dopamine. Abnormally released dopamine may participate in the development of l-DOPA-induced dyskinesias. Simultaneous activation of 5-HT1A and 5-HT1B receptors effectively blocks l-DOPA-induced dyskinesias in animal models of dopamine depletion, justifying a clinical study with eltoprazine, a 5-HT1A/

Possible future changes in cyclonic storms in the Bay of Bengal, India under warmer climate

The aim of this paper is to study the model's simulated frequency, track, intensity and location of cyclonic storms (CSs) and severe cyclonic storms (SCSs) in the Bay of Bengal (BoB), India. For the purpose, the PRECIS (Providing REgional Climates for Impacts Studies) a regional climate modelling system, of UK Met Office, is used. This model is integrated for the period 1961-1990 (baseline) and th

Normalyzer: A Tool for Rapid Evaluation of Normalization Methods for Omics Data Sets

High-throughput omics data often contain systematic biases introduced during various steps of sample processing and data generation. As the source of these biases is usually unknown, it is difficult to select an optimal normalization method for a given data set. To facilitate this process, we introduce the open-source tool "Normalyzer". It normalizes the data with 12 different normalization method