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Plausible Hypothesis (plausible + hypothesis)
Selected AbstractsWhy might language and motor impairments occur together?INFANT AND CHILD DEVELOPMENT, Issue 3 2003L.B. Estil Abstract A step-wise methodology is employed in order to identify common neurological factors underlying motor and language impairments where they occur together. A sample of 15 5,10-year-old children with predetermined language impairment was tested comprehensively using the Illinois Test of Psycholinguistic Ability (ITPA) and the Movement Assessment Battery for Children (Movement ABC). On the basis of these tests, only four of the sample were found to have generally poor performance both in psycholinguistic (particularly indexed by problems with visual closure and sound blending) and motor abilities (particularly indexed by manual dexterity problems,bimanual co-ordination and drawing,and static balance. Further detailed examination of the findings fostered a number of plausible hypotheses to account for this communality. The viability of these different alternatives is discussed. Copyright © 2003 John Wiley & Sons, Ltd. [source] Design Considerations for Research on Analytical ProceduresINTERNATIONAL JOURNAL OF AUDITING, Issue 3 2001Stephen K. Asare This article discusses research design considerations for conducting behavioral research on auditors' performance of analytical procedures (APs). With the trend in practice towards increasing reliance on APs, it is essential that auditors are proficient in completing such tests. Therefore, research to understand and improve auditors' performance of APs is important. Once an unexpected fluctuation is identified, APs involve three phases: generation of plausible hypotheses (likely causes); gathering evidence to examine plausible hypotheses; and identification of the most likely cause followed by appropriate follow-up actions. Although prior research has focused on these phases in isolation, they are, in fact, interrelated. Important research design issues and trade-offs for each of the phases of APs are discussed. For instance, in examining hypothesis generation there are choices as to the amount and nature of case background information, number of ratios or accounts to explain; ex-post evaluation of the quality of the hypothesis set; and instructions on number of causes that account for the fluctuation. Significant considerations are identified for making informed decisions among design choices. [source] Junk-food in marine ecosystemsOIKOS, Issue 7 2008Henrik Österblom The abundance and availability of food are critical determininants of reproductive success and population dynamics of marine top predators. However, recent work has indicated that the quality of the food may also be critically important for some marine predators. The ,junkfood hypothesis' was originally suggested as a potential explanation for a dramatic population decline of Stellers sea lions Eumetopias jubatus in the Gulf of Alaska. According to the hypothesis, a dietary switch to prey of low energy content led to detrimental effects on the population of sea lions. A number of observations indicate that the hypothesis is relevant for several population parameters. Recent work on piscivorous seabirds has provided substantial evidence indicating the relevance of this hypothesis in food webs in e.g. the North Pacific, the North Sea and the Baltic Sea. The emergence of ,junk-food' in these systems may be coupled to large scale changes in climatological and oceanographic forcing, although predation, fishing and competition provide additional plausible hypotheses. It may be possible to predict which kinds of animals will be particularly sensitive to food quality; these seem to be species with limited ability to carry food loads, with energetically-expensive foraging behaviour, and with digestive anatomy evolved to minimize mass at the cost of digestive efficiency. This review suggests that the junk-food hypothesis is a highly relevant factor in relation to sustaining ecosystem resilience, and is an important consideration in ecosystem management. Sustaining healthy populations of marine top-predators requires an understanding of the role of food quality, in addition to food abundance and availability. [source] Allonursing in Captive Guanacos, Lama guanicoe: Milk Theft or Misdirected Parental Care?ETHOLOGY, Issue 8 2009Beatriz Zapata Females in several ungulates transfer milk to non-filial (NF) offspring, in a process known as allonursing. This behavior is less common in monotocous species, including most ungulates, and it has been associated with parasitic behavior of calves or mothers who have lost their own offspring. To examine whether the calves ,steal' milk from the females or whether females fail to discriminate their own calves in guanacos, allonursing behavior was observed. If milk theft drives allonursing, mothers should reject NF offspring, they should search for their own calves, and calves attempting to suckle from alien mothers should adopt parallel (as opposed to the anti-parallel) position during allonursing. Alternatively, if allonursing is caused by mothers unable to discriminate own offspring, mothers are not expected to reject NF offspring, and alien calves should use parallel and antiparallel position similarly when allonursing. Allonursing was investigated during the first 3 mo of lactation in two groups of captive guanacos composed of 15 and 14 mother-calf pairs, respectively. While 40% and 62.5% of mothers in groups 1 and 2 performed allonursing, high individual variation prevailed; some females exhibited this behavior infrequently (4.1% and 6.5 % in groups 1 and 2). The rejection rate to NF nursing attempts was threefold higher than the rejection rate to filial nursing attempts. The occurrence of nursing to NF was associated to a parallel posture by the calves. Our findings suggest that ,milk theft' is a more plausible hypothesis to explain allonursing in guanacos than ,misdirected parental care'. [source] Endocrine disruptors and male reproductive function , a short reviewINTERNATIONAL JOURNAL OF ANDROLOGY, Issue S2 2000Sin-Eng Chia Semen quality has decline in many countries over the last few decades. There has been an increase in the incidence of testicular cancer world-wide. The incidences of cryptorchidism and hypospadias have also increased in many countries. A biological plausible hypothesis has suggested that man-made chemicals act as endocrine disruptors resulting in altered development of the reproductive tract causing the observed effects. Endocrine disruptors include natural products, pharmaceuticals, industrial products and environmental pollutants. There are limitations in the current in vivo and in vitro assays for the assessment of endocrine disruptors. Epidemiological human studies are necessary to fill in the gap of knowledge. Based on the current knowledge, the impact of endocrine disruptors on the male reproductive function remain to be appreciated. [source] Anatomy and ultrastructure of the reproductive organs in Dactylopodola typhle (Gastrotricha: Macrodasyida) and their possible functions in sperm transferINVERTEBRATE BIOLOGY, Issue 1 2008Alexander Kieneke Abstract. The reproductive anatomy of gastrotrichs is well known for several species, especially for the marine taxon Macrodasyida. However, there is little information on the reproductive organs and the modes of mating and sperm transfer in putative basal taxa, which is necessary for accurate reconstruction of the ground pattern of the Gastrotricha. We present the first detailed morphological investigation of the reproductive system of a putative basal gastrotrich, Dactylopodola typhle, using transmission and scanning electron microscopy, histology, and microscopic observations of living specimens. Dactylopodola typhle is a hermaphrodite that possesses paired female and male gonads, an unpaired uterus with an outlet channel that we call the cervix, and an additional accessory reproductive organ, the so-called caudal organ. We hypothesize that the hollow, secretory caudal organ serves for picking up autospermatozoa (self-sperm), for spermatophore formation, and finally for transferring the autospermatophore to a mating partner. The allospermatophore (foreign spermatophore) is stored within the uterus where fertilization occurs. We think that the mature and fertilized egg is released through the cervix and the dorsolateral female gonopore, and not by rupture of the body wall. Based on the morphology, we provide a plausible hypothesis for spermatophore formation and transfer in D. typhle. Preliminary phylogenetic considerations indicate that the stem species of Macrodasyida, perhaps that of all Gastrotricha, had paired ovaries and paired testes, an unpaired uterus, and only one accessory reproductive organ. [source] Ontogeny and homology of the claustra in Otophysan Ostariophysi (Teleostei)JOURNAL OF MORPHOLOGY, Issue 8 2006Ralf Britz Abstract We studied the ontogeny of the claustrum comparatively in representatives of all otophysan subgroups. The claustrum of cypriniforms has a cartilaginous precursor, the claustral cartilage, which subsequently ossifies perichondrally at its anterior face and develops an extensive lamina of membrane bone. The membrane bone component of the claustrum and its close association with the atrium sinus imparis, a perilymphatic space of the Weberian apparatus, are both synapomorphies of cypriniforms. The characiform claustrum is not preformed in cartilage and originates as a membrane bone ossification, a putative synapomorphy of that taxon. Among siluriforms, the claustrum is present only in more basal groups and originates as an elongate cartilage that ossifies in a characteristic ventrodorsal direction, possibly a synapomorphy of catfishes. Gymnotiforms lack the claustral cartilage and claustrum. We review all previous hypothesis of claustrum homology in light of the above findings and conclude that the most plausible hypothesis is the one originally proposed by Bloch ([1900] Jen Z Naturw 34:1,64) that claustra are homologs of the supradorsals of the first vertebra. J. Morphol. © 2006 Wiley-Liss, Inc. [source] Polyglutamine disease: Recent advances in the neuropathology of dentatorubral-pallidoluysian atrophyNEUROPATHOLOGY, Issue 4 2006Mitsunori Yamada Polyglutamine diseases are hereditary neurodegenerative disorders that are caused by the expansion of a CAG repeat in the causative genes. They comprise at least nine disorders, including DRPLA, HD, and Machado-Joseph disease. Initially, the discovery of neuronal intranuclear inclusions (NIIs) in human brains and in a murine model of HD provided a plausible hypothesis that the expression of expanded polyglutamine stretches leads to NII formation, resulting in neuronal cell death in selective brain regions characteristic to each disease. Recent studies, however, suggest that nuclear dysfunction, especially transcriptional abnormalities caused by the diffuse intranuclear accumulation of mutant proteins, plays a pivotal role in the development and progression of clinical symptoms. Polyglutamine diseases have a similarity with neuronal storage disease, and this pathological process might become a target for the establishment of an effective therapy for these diseases. [source] FOREIGN NETWORKS AND EXPORTS: RESULTS FROM INDONESIAN PANEL DATATHE DEVELOPING ECONOMIES, Issue 4 2008Fredrik SJÖHOLM F10; F23; L10 Most firms and plants in developing countries produce only for the domestic market and few are able to export. One plausible hypothesis is that foreign networks decrease export costs and that plants with large amounts of such networks will be relatively likely to start exporting. We focus on two types of foreign networks: foreign ownership and imports of intermediate products. Our results suggest that plants in Indonesian manufacturing with any foreign ownership are substantially more likely to start exporting than wholly domestically owned plants. The results remain robust to alternative model specifications and after controlling for other plant characteristics. There is no effect on exports of imports of intermediate products. [source] | |||||||||||||