Chitin-based poly(urea-urethane)s

Chitins of various origins in DMA-LiCl solution have been reacted with excess 1,6-diisocyanatohexane (three or twelve equivalents per repeating unit) for 4-20 h. The resulting solutions were exposed to water vapor for 2 days and flexible and opaque materials were produced, which upon drying yielded powders whose main characteristics were insolubility in aqueous and organic solvents, remarkable crystallinity, typical infrared spectrum, high N/C ratio (0.287), and a high degree of substitution (0.29). Under the SEM structural features reminiscent of chitin were absent but no thermoplastic behavior was found by differential scanning calorimetry. Chitosan was similarly treated under heterogeneous conditions in anhydrous pyridine, and yielded reaction products with a lower degree of substitution (0.17). With partially hydrolysed chitosan, highly crystalline products were obtained.     

Radiolabelled antimicrobial peptides for imaging of infections: a review

Risk factors suggestive of relatively late exposure to EBV have been consistently associated with Hodgkin's disease (HD) in younger adults. In addition, evidence of EBV infection has been found in the Reed-Sternberg cells themselves in about one-third to one-half of all HD cases. However, no study yet published has correlated these childhood social environment risk factors with the presence of EBV in Hodgkin's tumor cells. We examined whether EBV-positive HD occurs in those patients whose childhood environment would predispose them to relatively late exposure to EBV. The study population consisted of 102 cases of mixed cellularity (MC; n = 25) or nodular sclerosing (n = 77) HD. Samples that tested positive for either EBV-encoded RNA or latent membrane protein or both were considered EBV-positive. Of the 102 cases, 83 completed a questionnaire regarding childhood social environment. The association with EBV-positivity was estimated by the odds ratio (OR) with 95% confidence intervals (CI). Twenty-two percent of the cases were EBV-positive. These cases were more likely to be MC (OR, 6.2; CI, 2.3-16.3) and male (OR, 3.4; CI, 1.3-9.0). History of infectious mononucleosis (IM) was not predictive of EBV-positivity, with only 3 of 14 such patients being EBV-positive (P = 0.82). Contrary to our hypothesis, no association between EBV and childhood environment risk factors was identified. The association of EBV with MC histology and male gender agrees with previous reports. The most intriguing finding was the dissociation between IM history and EBV-positivity, in that almost all of the cases with a history of IM were EBV-negative.     

Linear response algorithms for approximate inference in graphical models

Belief propagation (BP) on cyclic graphs is an efficient algorithm for computing approximate marginal probability distributions over single nodes and neighboring nodes in the graph. However, it does not prescribe a way to compute joint distributions over pairs of distant nodes in the graph. In this article, we propose two new algorithms for approximating these pairwise probabilities, based on the linear response theorem. The first is a propagation algorithm that is shown to converge if BP converges to a stable fixed point. The second algorithm is based on matrix inversion. Applying these ideas to gaussian random fields, we derive a propagation algorithm for computing the inverse of a matrix.     

Building environmental assessment methods: applications and development trends

The construction and property sector has seen the development of a number of methods for evaluating the 'greenness' of buildings in the 1990s - both for new designs and existing buildings. These range from very detailed life cycle assessment methods, which account for all the embodied and operational environmental impacts of building materials, to higher level environmental impact assessment methods, which evaluate the broader implications of the building's impact on the environment. In between these two are environmental assessment methods such as BREEAM, BEPAC, LEED, and GBA. In this paper, we discuss the potential market applications of these systems and compare and contrast several of the major environmental assessment methods. Le secteur de la construction et de l'immobilier a ete le temoin du developpement d'un certain nombre de methodes permettant d'evaluer les performances ecologiques des batiments dans les annees 1990, tant sur le plan des nouveaux concepts que des batiments existants. Ces methodes vont de l'evaluation tres detailee du cycle de vie, qui tient compte de l'impact specifique et des incidences operationnelles des materiaux de construction sur l'environnement, jusqu'a une evaluation de l'impact environnemental a un niveau plus eleve. Entre ces deux extremes, on trouve des methodes d'evaluation environnementale telles que BREEAM, BEPAC, LEED et GBA. Dans cet article, nous examinons les applications commerciales potentielles des ces systemes; nous comparons, en les opposant, plusieurs methodes majeures d'evaluation environnementale.     

The Intuitive Process: The Case of Psychotherapy.

Intuition may be considered a common factor in psychotherapy, characterizing both psychotherapist and client functioning. After reviewing existing models for intuition, the author proposes a 5-phase model to explain intuition on the basis of the cognitive functions of pattern discovery and recognition. It is argued that intuition should not be viewed as a single phenomenon; rather, the phenomena labeled as intuition can be understood as belonging to different phases of a single process. These phases consist of early knowledge representations that demonstrate the creative role that intuition may play in the construction of knowledge. The author illustrates this model by presenting examples from the practice of psychotherapy. Finally, the author discusses the possibilities of promoting intuitive insight, the fallibility of intuition, and the role intuition may play in integrative decision making. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Buchbesprechungen

European Journal of Wood and Wood Products -     

Überprüfung berechneter Trocknungsspannungs-Verteilungen durch einen experimentellen quantitativen Spannungsnachweis

Results of simulation models for the calculation of drying stresses, which develop during kiln drying of timber, can only be proved by experimental examination. A method for destructive testing of stress distributions is introduced. The validity of a calculation algorithm for the continuous determination of drying stresses during kiln drying is discussed by comparing calculated and experimental results.