7 resultados para Special basic commutative difference operators,

em BORIS: Bern Open Repository and Information System - Berna - Suiça


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Symptom development during the prodromal phase of psychosis was explored retrospectively in first-episode psychosis patients with special emphasis on the assumed time-related syndromic sequence of "unspecific symptoms (UN)-predictive basic symptoms (BS)-attenuated psychotic symptoms (APS)-(transient) psychotic symptoms (PS)." Onset of syndromes was defined by first occurrence of any of their respective symptoms. Group means were inspected for time differences between syndromes and influence of sociodemographic and clinical characteristics on the recalled sequence. The sequence of "UN-BS/APS-PS" was clearly supported, and both BS and, though slightly less, APS were highly sensitive. However, onset of BS and APS did not show significant time difference in the whole sample (N = 126; 90% schizophrenia), although when each symptom is considered independently, APS tended to occur later than first predictive BS. On descriptive level, about one-third each recalled an earlier, equal and later onset of BS compared with APS. Level of education showed the greatest impact on the recall of the hypothesized sequence. Thereby, those with a higher school-leaving certificate supported the assumed sequence, whereas those of low educational background retrospectively dated APS before BS. These findings rather point out recognition and recall bias inherent to the retrospective design than true group characteristics. Future long-term prospective studies will have to explore this conclusively. However, as regards the criteria, the results support the notion of BS as at least a complementary approach to the ultrahigh risk criteria, which may also allow for an earlier detection of psychosis.

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BACKGROUND: Physiological data obtained with the pulmonary artery catheter (PAC) are susceptible to errors in measurement and interpretation. Little attention has been paid to the relevance of errors in hemodynamic measurements performed in the intensive care unit (ICU). The aim of this study was to assess the errors related to the technical aspects (zeroing and reference level) and actual measurement (curve interpretation) of the pulmonary artery occlusion pressure (PAOP). METHODS: Forty-seven participants in a special ICU training program and 22 ICU nurses were tested without pre-announcement. All participants had previously been exposed to the clinical use of the method. The first task was to set up a pressure measurement system for PAC (zeroing and reference level) and the second to measure the PAOP. RESULTS: The median difference from the reference mid-axillary zero level was - 3 cm (-8 to + 9 cm) for physicians and -1 cm (-5 to + 1 cm) for nurses. The median difference from the reference PAOP was 0 mmHg (-3 to 5 mmHg) for physicians and 1 mmHg (-1 to 15 mmHg) for nurses. When PAOP values were adjusted for the differences from the reference transducer level, the median differences from the reference PAOP values were 2 mmHg (-6 to 9 mmHg) for physicians and 2 mmHg (-6 to 16 mmHg) for nurses. CONCLUSIONS: Measurement of the PAOP is susceptible to substantial error as a result of practical mistakes. Comparison of results between ICUs or practitioners is therefore not possible.

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BACKGROUND: Knowledge of how CFTR mutations other than F508del translate into the basic defect in cystic fibrosis (CF) is scarce due to the low incidence of homozygous index cases. METHODS: 17 individuals who are homozygous for deletions, missense, stop or splice site mutations in the CFTR gene were investigated for clinical symptoms of CF and assessed in CFTR function by sweat test, nasal potential difference and intestinal current measurement. RESULTS: CFTR activity in sweat gland, upper airways and distal intestine was normal for homozygous carriers of G314E or L997F and in the range of F508del homozygotes for homozygous carriers of E92K, W1098L, R553X, R1162X, CFTRdele2(ins186) or CFTRdele2,3(21 kb). Homozygotes for M1101K, 1898+3 A-G or 3849+10 kb C-T were not consistent CF or non-CF in the three bioassays. 14 individuals exhibited some chloride conductance in the airways and/or in the intestine which was identified by the differential response to cAMP and DIDS as being caused by CFTR or at least two other chloride conductances. DISCUSSION: CFTR mutations may lead to unusual electrophysiological or clinical manifestations. In vivo and ex vivo functional assessment of CFTR function and in-depth clinical examination of the index cases are indicated to classify yet uncharacterised CFTR mutations as either disease-causing lesions, risk factors, modifiers or neutral variants.

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An approach for the determination of atomization energies based on the extrapolated difference technique in the framework of Knudsen effusion mass spectrometry is proposed. Its essence is the use of thermodynamic data for the determination of the appearance energy of fragment ions of a reference and a special mathematical treatment of the ionization efficiency functions. The advantages of this approach are demonstrated for the cases of incongruently vaporizing lanthanide bromides that suffer from decomposition or disproportionation at high temperatures. The atomization energies for SmBr2 (7.78±0.12 eV), EuBr2 (7.51±0.11 eV), YbBr2 (7.25±0.13 eV), SmBr3 (11.09±0.10 eV), and YbBr3 (10.23±0.09 eV) molecules have been determined for the first time.

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Despite being one of the most extensively researched of Eastern Himalayan languages, the basic morphological and phonological-prosodic properties of Apatani (Tibeto-Burman > Tani > Western) have not yet been adequately described. This article attempts such a description, focusing especially on interactions between segmental-syllabic phonology and tone in Apatani. We highlight three features in particular – vowel length, nasality and a glottal stop – which contribute to contrastively-weighted syllables in Apatani, which are consistently under-represented in previous descriptions of Apatani, and in absence of which tone in Apatani cannot be effectively analysed. We conclude that Apatani has two “underlying”, lexically-specified tone categories H and L, whose interaction with word structure and syllable weight produce a maximum of three “surface” pitch contours – level, falling and rising – on disyllabic phonological words. Two appendices provide a set of diagnostic procedures for the discovery and description of Apatani tone categories, as well as an Apatani lexicon of approximately one thousand entries.

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We study representations of MV-algebras -- equivalently, unital lattice-ordered abelian groups -- through the lens of Stone-Priestley duality, using canonical extensions as an essential tool. Specifically, the theory of canonical extensions implies that the (Stone-Priestley) dual spaces of MV-algebras carry the structure of topological partial commutative ordered semigroups. We use this structure to obtain two different decompositions of such spaces, one indexed over the prime MV-spectrum, the other over the maximal MV-spectrum. These decompositions yield sheaf representations of MV-algebras, using a new and purely duality-theoretic result that relates certain sheaf representations of distributive lattices to decompositions of their dual spaces. Importantly, the proofs of the MV-algebraic representation theorems that we obtain in this way are distinguished from the existing work on this topic by the following features: (1) we use only basic algebraic facts about MV-algebras; (2) we show that the two aforementioned sheaf representations are special cases of a common result, with potential for generalizations; and (3) we show that these results are strongly related to the structure of the Stone-Priestley duals of MV-algebras. In addition, using our analysis of these decompositions, we prove that MV-algebras with isomorphic underlying lattices have homeomorphic maximal MV-spectra. This result is an MV-algebraic generalization of a classical theorem by Kaplansky stating that two compact Hausdorff spaces are homeomorphic if, and only if, the lattices of continuous [0, 1]-valued functions on the spaces are isomorphic.

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Minimal residual disease (MRD) is a major hurdle in the eradication of malignant tumors. Despite the high sensitivity of various cancers to treatment, some residual cancer cells persist and lead to tumor recurrence and treatment failure. Obvious reasons for residual disease include mechanisms of secondary therapy resistance, such as the presence of mutant cells that are insensitive to the drugs, or the presence of cells that become drug resistant due to activation of survival pathways. In addition to such unambiguous resistance modalities, several patients with relapsing tumors do not show refractory disease and respond again when the initial therapy is repeated. These cases cannot be explained by the selection of mutant tumor cells, and the precise mechanisms underlying this clinical drug resistance are ill-defined. In the current review, we put special emphasis on cell-intrinsic and -extrinsic mechanisms that may explain mechanisms of MRD that are independent of secondary therapy resistance. In particular, we show that studying genetically engineered mouse models (GEMMs), which highly resemble the disease in humans, provides a complementary approach to understand MRD. In these animal models, specific mechanisms of secondary resistance can be excluded by targeted genetic modifications. This allows a clear distinction between the selection of cells with stable secondary resistance and mechanisms that result in the survival of residual cells but do not provoke secondary drug resistance. Mechanisms that may explain the latter feature include special biochemical defense properties of cancer stem cells, metabolic peculiarities such as the dependence on autophagy, drug-tolerant persisting cells, intratumoral heterogeneity, secreted factors from the microenvironment, tumor vascularization patterns and immunosurveillance-related factors. We propose in the current review that a common feature of these various mechanisms is cancer cell dormancy. Therefore, dormant cancer cells appear to be an important target in the attempt to eradicate residual cancer cells, and eventually cure patients who repeatedly respond to anticancer therapy but lack complete tumor eradication.