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It is well known that one of the features of long-memory processes is that they tend to have what looks like trends and cycles. A consequence of this property is that it is difficult to distinguish a long-memory process from a nonstationary process. In this paper, we study the impact of the periodicity and trend on different methods for estimating the long-memory processes parameter d.

A number of statistical techniques to analyze and model coastal morphological evolution over yearly and decadal (i.e., long-term) time scales based on field data are presented. After a general introduction to long-term morphological modeling, mainly linear methods are discussed, whereas nonlinear methods are treated in a companion paper (SOUTHGATE et al., 2001). The theoretical background to the m

Models based on generalized plant physiological theory represent a promising approach for describing vegetation responses to environmental drivers on large scales but must be tested for their ability to reproduce features of real vegetation. We tested the capability of a generalized vegetation model (LPJ-GUESS) to simulate vegetation structural and compositional dynamics under various disturbance

Many animals have been shown to use the pattern of polarized light in the sky as an optical compass. Specialised photoreceptors are used to analyse this pattern. We here present evidence for an eye design suitable for polarized skylight navigation in the flightless desert scarab Pachysoma striatum. Morphological and electrophysiological studies show that an extensive part of the dorsal eye is equi

Popular Abstract in Swedish Ett strategiskt ramverk för hållbar industriell utveckling i Afrika söder om Sahara: En system evolutionär ansats.The principal objectives of this research were: · to develop a conceptual framework on sustainability and sustainable development and · to propose a strategy framework for sustainable industrial development in Sub-Saharan Africa (SSA). The research was done based on systems evolutionary approach having the following methodological principles as a guide. · The dynamic complexity of environmental an

The kinetics of the selective catalytic reduction of nitric oxides (NOx) on a proprietary high temperature catalyst with diesel as the reductant have been studied. The objective was to derive a kinetic model that can be used for real time simulation of the catalyst. In the extension, the real time simulation will be used when controlling the injection of reductant. This is a requirement for achiev

Objective: To evaluate whether the free-to-total prostate-specific antigen (F/T-PSA) ratio can be used to differentiate between stage pT2 and pT3 prostate cancer. Material and Methods: A total of 176 consecutive patients from the Goteborg Screening Study (median T-PSA 4.2 ng/ml) who underwent radical prostatectomy (without neoadjuvant hormonal therapy) were included in the study. The pT stage was

The addition of a carbon nutrient feed to a fed-batch cultivation is often not enough to obtain satisfactory growth and/or production. In some cases, an additional feed with for example supplementary amino acids or complex media is required. This work presents the development of feeding strategies where more than one feed is required and the knowledge of the growth requirements is low. Simulations

Artikeln beskriver olika stadier i Theissens uppmärksammade forskning om evangeliernas tillkomstprocess och den historiske Jesus, med särskild uppmärksamhet på hans sena huvudarbeten. Theissen är numera kritisk mot den formhistoriska skepsis som läser evangelierna som en spegel av den tidiga kyrkan i stället för av Jesus. Idag hävdar han plausibilitetskriteriet som det avgörande. Just det att Jesu

This paper reports the implementation of the SIMIND Monte Carlo code on an IBM SP2 distributed memory parallel computer. Basic aspects of running Monte Carlo particle transport calculations on parallel architectures are described. Our parallelization is based on equally partitioning photons among the processors and uses the Message Passing Interface (MPI) library for interprocessor communication a

One of the most fundamental components of predator-prey models is encounter rate, modelled as the product of prey density and search efficiency. Encounter rates have, however, rarely been measured in empirical studies. In this study, we used a video system approach to estimate how encounter rates between piscivorous fish that use a sit-and-wait foraging strategy and their prey depend on prey densi

Cryptobiosis is an ametabolic state of life entered by some lower organisms (among metazoans mainly rotifers, tardigrades and nematodes) in response to adverse environmental conditions. Despite a long recognition of cryptobiotic organisms, the evolutionary origin and life history consequences of this biological phenomenon have remained unexplored. We present one of the first theoretical models on

This PhD thesis is made up of five independent studies and a comprehensive synthesis. The first three studies are published 2001 in the book Vem behöver en by? Kyrkheddinge, struktur och strategi under tusen år (pp. 1-95) (Who needs a village? Kyrkheddinge, Structure and Strategy During a Thousand Years). The remaining two parts and the synthesis are published in the volume Den medeltida byns soci