Manage Your \u27Blind Flight\u27 - The Optimal Timing for IT Project Re-Evaluation

As the value of an IT project can change over time, management is in blind flight about the state of the project until the project has been re-evaluated. As each evaluation causes costs, continuous evaluation is economically unreasonable. Nevertheless, the blind flight should not take too long, because the project value can considerably deviate from its initial estimation and high losses can occur. To trade off costs of re-evaluation and potential loss of project value, this paper will elaborate upon an economic model that is able to determine the optimal time until re-evaluation considering the risky cash flows of a project. Based on a simulation, we find that it makes good economic sense to optimize the interval of re-evaluation. Therefore, companies are able to avoid financial loss caused by evaluating too early as well as hazarding project value caused by evaluating too late

ALIENAÇÃO PARENTAL: VISÃO JURÍDICA EM UMA ANÁLISE PSICOLÓGICA

RESUMO   O presente artigo visa apresentar uma abordagem do tema alienação parental e síndrome de alienação parental como fenômeno social e familiar inserido no atual contexto da sociedade moderna. O objetivo geral do estudo é compreender aspectos da alienação parental nos âmbitos psicológicos e jurídicos através de uma revisão literária na identificação de aspectos comportamentais das crianças, alienadores e alienados que poderiam propiciar conflitos na qualidade de vida das famílias envolvidas. Objeto do estudo é também diferenciar alienação parental de síndrome de alienação parental e conhecer os danos psicológicos relacionados à alienação a fim de oportunizar uma visão ampliada do problema investigado.   Palavras chaves: Alienação parental, Síndrome de alienação parental, Danos psicológicos

Natural and Design Science Perspective on the Business Value of IT

This paper provides a structured overview of selected articles concerning the research on the Business Value of IT. It aims to identify key themes within this field, as well as research gaps. As our guiding framework, we divided the literature to two categories reflecting the main approaches within IS business value research: First, papers that can be assigned to the Natural Sciences Paradigm dealing with the question of how and why IS/IT create value. Second, papers that are based on the Design Science Paradigm dealing with the actual realization and evaluation of the BVIT, which are the key subjects from a management point of view. In a third step, we identify research that combines both paradigms, since the combination of the two research paradigms would be valuable for both research streams

Protein SRP54 iz morske spužve Geodia cydonium

In the systematic search for phylogenetically conserved proteins in the simplest and most ancient extant metazoan phylum – Porifera, we have identified and analyzed a cDNA encoding the signal recognition particle 54 kD protein (SRP54) from the marine sponge Geodia cydonium (Demospongiae). The signal recognition particle (SRP) is a universally conserved ribonucleoprotein complex of a very ancient origin, comprising SRP RNA and several proteins (six in mammals). The nucleotide sequence of the sponge cDNA predicts a protein of 499 amino acid residues with a calculated Mr of 55175. G. cydonium SRP54 displays unusually high overall similarity (90 %) with human/mammalian SRP54 proteins, higher than with Drosophila melanogaster (88 %), or Caenorhabditis elegans (82 %). The same was found for the majority of known and phylogenetically conserved proteins from sponges, indicating that the molecular evolutionary rates in protein coding genes in Porifera as well as in highly developed mammals (vertebrates) are slower, when compared with the rates in homologous genes from invertebrates (insects, nematodes). Therefore, genes/proteins from sponges might be the best candidates for the reconstruction of ancient structures of proteins and genome/proteome complexity in the ancestral organism, common to all multicellular animals.U sistematskoj potrazi za filogenetski sačuvanim proteinima u spužava, najjednostavnijih i najstarijih živućih Metazoa, autori su identificirali i analizirali cDNA koja kodira protein SRP54 u morske spužve Geodia cydonium. SRP54 je evolucijski najsačuvaniji protein ribonukleoproteinskoga kompleksa SRP (signal recognition particle), odgovornog za translokaciju sekretornih i transmembranskih proteina. SRP je nastao vrlo rano u evoluciji i svugdje je prisutan u živom svijetu, od bakterija do čovjeka. cDNA spužve G. cydonium kodira protein SRP54 dug 499 aminokiselina, izračunate molekularne mase 55175, koji pokazuje najviši stupanj sličnosti (90 %) s ljudskim proteinom SRP54, više nego sa SRP54 iz kukca Drosophila melanogaster (88 %) ili oblića Caenorhabditis elegans (82 %). Velika sličnost proteina spužava s homolozima u sisavaca uočena u ovom radu, kao i u našim prijašnjim istraživanjima, upućuje na sporije evolucijske promjene u genima spužava i sisavaca (kralježnjaka) u usporedbi s ubrzanijim promjenama u genima kukaca i oblića (beskralježnjaka). Geni/proteini spužava su stoga posebno korisni za rekonstrukciju strukture proteina i kompleksnosti genoma/proteoma u ancestralnom organizmu koji je bio zajednički predak svih višestaničnih životinja

Plasmodium infection alters Anopheles gambiae detoxification gene expression

ABSTRACT: BACKGROUND: Anopheles gambiae has been shown to change its global gene expression patterns upon Plasmodium infection. While many alterations are directly related to the mosquito's innate immune response, parasite invasion is also expected to generate toxic by-products such as free radicals. The current study aimed at identifying which loci coding for detoxification enzymes are differentially expressed as a function of Plasmodium berghei infection in midgut and fat body tissues. RESULTS: Using a custom-made DNA microarray, transcript levels of 254 loci primarily belonging to three major detoxification enzyme families (glutathione S-transferases, cytochrome P450 monooxygenases and esterases) were compared in infected and uninfected mosquitoes both during ookinete invasion and the release of sporozoites into the hemocoel. The greatest changes in gene expression were observed in the midgut in response to ookinete invasion. Interestingly, many detoxification genes including a large number of P450s were down-regulated at this stage. In the fat body, while less dramatic, gene expression alterations were also observed and occurred during the ookinete invasion and during the release of sporozoites into the hemocoel. While most gene expression changes were tissue-related, CYP6M2, a CYP previously associated with insecticide resistance, was over-expressed both in the midgut and fat body during ookinete invasion. CONCLUSIONS: Most toxicity-related reactions occur in the midgut shortly after the ingestion of an infected blood meal. Strong up-regulation of CYP6M2 in the midgut and the fat body as well as its previous association with insecticide resistance shows its broad role in metabolic detoxificatio

The ABCG2 efflux transporter from rabbit placenta: Cloning and functional characterization

AbstractIn human placenta, the ATP-binding cassette efflux transporter ABCG2 is highly expressed in syncytiotrophoblast cells and mediates cellular excretion of various drugs and toxins. Hence, physiological ABCG2 activity substantially contributes to the fetoprotective placenta barrier function during gestation. Developmental toxicity studies are often performed in rabbit. However, despite its toxicological relevance, there is no data so far on functional ABCG2 expression in this species. Therefore, we cloned ABCG2 from placenta tissues of chinchilla rabbit. Sequencing showed 84–86% amino acid sequence identity to the orthologues from man, rat and mouse. We transduced the rabbit ABCG2 clone (rbABCG2) in MDCKII cells and stable rbABCG2 gene and protein expression was shown by RT-PCR and Western blot analysis. The rbABCG2 efflux activity was demonstrated with the Hoechst H33342 assay using the specific ABCG2 inhibitor Ko143. We further tested the effect of established human ABCG2 (hABCG2) drug substrates including the antibiotic danofloxacin or the histamine H2-receptor antagonist cimetidine on H33342 accumulation in MDCKII-rbABCG2 or -hABCG2 cells. Human therapeutic plasma concentrations of all tested drugs caused a comparable competitive inhibition of H33342 excretion in both ABCG2 clones. Altogether, we first showed functional expression of the ABCG2 efflux transporter in rabbit placenta. Moreover, our data suggest a similar drug substrate spectrum of the rabbit and the human ABCG2 efflux transporter

The role of cover crops for cropland soil carbon, nitrogen leaching, and agricultural yields – a global simulation study with LPJmL (V. 5.0-tillage-cc)

Land management practices can reduce the environmental impact of agricultural land use and production, improve productivity, and transform cropland into carbon sinks. In our study we assessed the biophysical and biogeochemical impacts and the potential contribution of cover crop practices to sustainable land use. We applied the process-based, global dynamic vegetation model LPJmL (Lund–Potsdam–Jena managed Land) V. 5.0-tillage-cc with a modified representation of cover crops to simulate the growth of grasses on cropland in periods between two consecutive main crops' growing seasons for near-past climate and land use conditions. We quantified simulated responses of agroecosystem components to cover crop cultivation in comparison to bare-soil fallowing practices on global cropland for a period of 50 years. For cover crops with tillage, we obtained annual global median soil carbon sequestration rates of 0.52 and 0.48 t C ha−1 yr−1 for the first and last decades of the entire simulation period, respectively. We found that cover crops with tillage reduced annual nitrogen leaching rates from cropland soils by medians of 39 % and 54 % but also the productivity of the following main crop by an average of 1.6 % and 2 % for the 2 analyzed decades. The largest reductions in productivity were found for rice and modestly lowered ones for maize and wheat, whereas the soybean yield revealed an almost homogenously positive response to cover crop practices replacing bare-soil fallow periods. The obtained simulation results of cover crop with tillage practices exhibit a good ability of the model version to reproduce observed effects reported in other studies. Further, the results suggest that having no tillage is a suitable complementary practice to cover crops, enhancing soil carbon sequestration and the reduction in nitrogen leaching, while reducing potential trade-offs with the main-crop productivity due to their impacts on soil nitrogen and water dynamics. The spatial heterogeneity of simulated impacts of cover crops on the variables assessed here was related to the time period since the introduction of the management practice as well as to environmental and agronomic conditions of the cropland. This study supports findings of other studies, highlighting the substantial potential contribution of cover crop practices to the sustainable development of arable production.Peer Reviewe