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Critical Phase (critical + phase)
Selected AbstractsThe new adhesion prophylaxis membrane A-part®,From in vitro testing to first in vivo resultsJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2009Bernd Martin Jaenigen Abstract Introduction: Formation of postoperative intra-abdominal adhesions is a severe problem in surgery. Apart from standard surgical procedures, a variety of different substances is available to prevent adhesions, but no universal method has been developed so far. A membrane consisting of polyvinyl alcohol (PVA) and carboxymethylcellulose (CMC) has been demonstrated to be antiadhesive. Here, the in vitro testing and first in vivo results in a rabbit sidewall model are reported. Materials and Methods: A-part® membrane contains a PVA/CMC mixture in a thickness of 40 ,m. The composition, dissolution, tensile strength, and elasticity were examined to characterize the membrane in vitro. Experiments in vivo were carried out using a ,rabbit sidewall model' in which a standardized peritoneal trauma was covered with a 5 × 6 cm A-part® membrane. Adhesion formation in A-part®-treated animals was compared with that in Adept® (15 mL/kg body weight) and untreated controls. Results: An 80/20 PVA/CMC mixture forms a stable, elastic, transparent membrane, which can easily be placed intraoperatively. The dissolution shows a half-life of about 2 weeks [day 15: (45.1 ± 4.9)% SD], which affords good adhesion protection during the initial critical phase of adhesion formation. In wet conditions, the membrane follows abdominal movements without tearing (tensile strength 5.0 ± 4.2 N/cm SD; elasticity 29.5%). In a rabbit sidewall model, A-part® membrane significantly reduced adhesion development by (83.1 ± 31.5)% SD compared with the control and the Adept group (p < 0.001). Conclusion: The properties of the A-part® membrane suggest that it may be useful as an antiadhesive in surgery. A-part® is effective in invivo testing as determined in a rabbit sidewall model. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009 [source] THE IDEA OF DEFENSE IN HISTORICAL AND CONTEMPORARY THINKING ABOUT JUST WARJOURNAL OF RELIGIOUS ETHICS, Issue 4 2008James Turner Johnson ABSTRACT What is, or should be, the role of defense in thinking about the justification of use of armed force? Contemporary just war thinking prioritizes defense as the principal, and perhaps the only, just cause for resorting to armed force. By contrast, classic just war tradition, while recognizing defense as justification for use of force by private persons, did not reason from self-defense to the justification of the use of force on behalf of the political community, but instead rendered the idea of just cause for resort to force in terms of the sovereign's responsibility to maintain justice, vindicating those who had suffered from injustice and punishing evildoers. This paper moves through three major stages in the historical development of just war thinking, first examining a critical phase in the formation of the classical idea of just cause as the responsibility to maintain justice, then discussing the shift, characteristic of the modern period, to an idea of sovereignty as connected to the state and the prioritization of defense of the state as just cause for use of force, and lastly showing how this conception of the priority of defense became part of the recovery of just war thinking in the latter part of the twentieth century. The paper concludes by noting recent changes in thought on international law that tend to emphasize justice at the expense of the right of self-defense, suggesting that the roots of just war thinking imply the need for a similar rethinking of contemporary just war discourse. [source] Development of Low-Firing B-Fluxed Stoneware TilesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 11 2009Alessandro F. Gualtieri In a global period of economic recession, innovation is a key requisite to get over this critical phase and prompt an upturn in the economy. Even the market of traditional ceramics is in a stalemate and producers desperately seek for new ideas which may supersede the long-used stoneware tiles. This paper presents the full characterization of a new potential class of ceramics named low-temperature stoneware tiles, highlighting their advantages and disadvantages. The body formulation and the firing process are both covered by an Italian Patent. This innovative product exhibits technological and esthetical features analogous to those of the traditional stoneware tile bodies but is fired at a maximum temperature of 950°C, about 250°C lower than the firing temperature of stoneware tiles. This is possible thanks to the addition of a B-rich frit to the mixture composed of quartz, feldspars, and clays. The frit acts as a low-temperature flux and promotes the melting of the feldspars. Within the fired body, the residual phases are quartz and feldspars. The newly formed phases can be ,-spodumene if Li is present in the frit or spinel if Mg is present in the natural materials. The best body formulations have been characterized with mineralogical, microscopic, and technological methods. The major weakness of these ceramic bodies is their unresistance to acids. The chemical nature of the sintered matrix, with a high content of alkalies and B, triggers off the tendency of the ceramic body to react in contact with acidic solutions. Another penalty factor is the cost of the B-rich frit used in the formulation of the ceramic mixture which increases the overall cost of the ceramic body. [source] Anti-predator behaviour, space use and habitat selection in female roe deer during the fawning season in a wolf areaJOURNAL OF ZOOLOGY, Issue 3 2008P. Bongi Abstract This study investigated the anti-predator strategies adopted by 19 radio-collared female roe deer during the fawning season by monitoring their spatial behaviour and habitat selection by means of radio-tracking. The study was carried out in a forest area of the Apennine Mountains (central Italy), where wolves are natural predators of roe deer and in summer fawns are more frequently predated than adult roe deer. The presence of fawns was monitored by means of direct observations. Roe deer fawns are known to adopt the hiding strategy during the lactation period, when they lie concealed for long periods waiting for their mothers' milk. As a consequence of this, the home-range sizes of mothers were significantly smaller than those of non-mothers during the summer lactation only. In contrast, no significant difference was found in spring, when fawns were absent, or autumn, when they were already weaned. In order to increase the success of the hiding strategy adopted by their fawns against wolf predation, mothers selected denser habitats (deciduous coppice forests) that provided denser undergrowth vegetation and limited visibility. In doing so, mothers traded open areas for forests throughout the fawning season. Indeed, mothers made significant habitat selection throughout the monitored period, and this was marked after the birth of fawns. In contrast, non-mothers generally used habitat types according to their availability. During lactation, the correlation between habitat use by mothers and habitat visibility (assessed using the form of a standard-sized roe deer) was inversely significant. These results taken together highlight the importance of anti-predator strategies adopted by roe deer mothers during the critical phase for fawn survival. [source] Calibration of pesticide leaching models: critical review and guidance for reportingPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 8 2002Igor G Dubus Abstract Calibration of pesticide leaching models may be undertaken to evaluate the ability of models to simulate experimental data, to assist in their parameterisation where values for input parameters are difficult to determine experimentally, to determine values for specific model inputs (eg sorption and degradation parameters) and to allow extrapolations to be carried out. Although calibration of leaching models is a critical phase in the assessment of pesticide exposure, lack of guidance means that calibration procedures default to the modeller. This may result in different calibration and extrapolation results for different individuals depending on the procedures used, and thus may influence decisions regarding the placement of crop-protection products on the market. A number of issues are discussed in this paper including data requirements and assessment of data quality, the selection of a model and parameters for performing calibration, the use of automated calibration techniques as opposed to more traditional trial-and-error approaches, difficulties in the comparison of simulated and measured data, differences in calibration procedures, and the assessment of parameter values derived by calibration. Guidelines for the reporting of calibration activities within the scope of pesticide registration are proposed. © 2002 Society of Chemical Industry [source] Catalase inhibition alters suberization and wound healing in potato (Solanum tuberosum) tubersPHYSIOLOGIA PLANTARUM, Issue 3 2007Mohammed Bajji In response to wounding, potato (Solanum tuberosum L.) tubers generate hydrogen peroxide (H2O2) in association with suberization, a critical phase of the wound-healing process. In the present study, the effect of aminotriazole (AT), a catalase (CAT, EC 1.11.1.6) inhibitor, on cut tubers was investigated using fresh weight (FW) loss and pathogen attack symptoms as indicators of wound-healing efficiency. Seven days after treatment, AT-treated tuber halves lost more FW and developed infection signs compared with the controls. Thiourea, another CAT inhibitor, as well as exogenous H2O2 treatments induced the same effects as AT suggesting that the alteration of the wound healing may be caused by CAT inhibition and the resulting accumulation of H2O2. Using transgenic tubers, FW losses 1 week after wounding were either higher (CAT repression) or lower (CAT overexpression) than those of the wild-type. When tuber halves were allowed to wound heal for different periods before treatment, AT had no effect on the progress of their wound healing if wound-healed for at least 3 days. This implies that AT may affect early wound-healing-related events, especially those occurring before or during suberization. A time-course analysis of the effects of AT treatment on wounded tuber tissues revealed that AT prevented the deposition of the polyphenolic domain of suberin in association with CAT inhibition and H2O2 accumulation. These data are important in identifying factors that may be required to regulate suberization and contribute to a better understanding of this critical process to hasten its rate and limit wound-related losses in stored potato tubers. [source] Verticillium longisporum and V. dahliae: infection and disease in Brassica napusPLANT PATHOLOGY, Issue 1 2006L. Zhou Verticillium wilt of oilseed rape (Brassica napus) is caused primarily by Verticillium longisporum and has become a serious problem in northern Europe. In order to evaluate whether V. longisporum and V. dahliae differ in their interaction with oilseed rape, phenotypical and molecular assessments were made. Oilseed rape plants for fungal assessments were inoculated with V. longisporum and V. dahliae via root-dipping and samples were taken from roots, stems, leaves, flowers, pods and seeds during plant development. The infection by V. longisporum was found to start mainly in lateral roots and root-hairs, followed by colonization of the xylem vessels and extensive spread in stems and leaves, whereas V. dahliae infected the main roots and remained in the region below the cotyledon node of the plants. Re-isolation studies, together with PCR analysis of samples taken from early growth stages through to fully ripe plants, showed that the onset of flowering was a critical phase for V. longisporum to colonize plants. No seeds infected with V. longisporum were found. Mycelial growth from V. dahliae but not V. longisporum was significantly reduced on media containing tissue from a low glucosinolate B. napus genotype compared with growth on media containing tissue from a high glucosinolate cultivar. The results of this study suggest that V. longisporum favours B. napus as host and that the transition from the vegetative to the generative phase is of importance for the spread of the fungus in oilseed rape plants. [source] Associations among symptoms of dieback in even-aged stands of ash (Fraxinus excelsior L.)FOREST PATHOLOGY, Issue 1 2010J. P. Skovsgaard Summary The objective of this study was to establish statistically based associations among macroscopic symptoms of crown dieback, cankers due to Chalara fraxinea, and symptoms caused by other pathogens and pests on Fraxinus excelsior. A total of 454 trees were observed in two plots of a 15-year-old experimental stand. The symptoms included: (i) overall extent of crown dieback; (ii) dieback of upper parts of the crown; (iii) canker in upper parts of the crown; (iv) wilting foliage; (v) cankers and bark proliferations at the lower part of the stem; and (vi) discolouration at stump or stem base. The analysis suggested that the observed symptoms of crown dieback are caused by a primary disease. The macroscopic symptoms attributed to dieback and canker in the crown were strongly associated. Moreover, the disease was associated with symptoms of Armillaria gallica, but no associations were found for symptoms of Neonectria galligena, Pseudomonas syringae subsp. savastanoi pv. fraxini, Hylesinus fraxini or H. varius when considered collectively. Dieback was more frequent on trees of average or below-average size, suggesting that individual tree resistance decreased with decreasing growth potential or tree vigour. The extent of canker in the crown depended on site conditions and possibly on silvicultural practices. The development of phytosanitary prescriptions for silviculture should primarily be targeted towards young stands as these represent the most critical phases of stand development. [source] Theorizing Diaspora: Perspectives on "Classical" and "Contemporary" DiasporaINTERNATIONAL MIGRATION, Issue 2 2004Michele Reis Cohen (1997) employed the term "classical" diaspora in reference to the Jews. Indeed, a vast corpus of work recognizes the Jewish people as examples of quintessential diasporic groups. However, a broader conceptualization of the term diaspora allows for the inclusion of immigrant communities that would be otherwise sidelined in the conventional literature on diaspora. This study is therefore a departure from the traditional diasporic literature, which tends to use the Jewish Diaspora as the archetype. It favours, rather, the classification of three principal broad historical waves in which the Jewish Diaspora can be interpreted as part of a classical period. The historicizing of diasporization for the purpose of this paper is achieved by an empirical discussion of the three major historical waves that influenced the diasporic process throughout the world: the Classical Period, the Modern Period, and the Contemporary or Late-modern Period. The paper discusses these three critical phases in the following manner: first, reference is made to the Classical Period, which is associated primarily with ancient diaspora and ancient Greece. The second historical phase analyses diaspora in relation to the Modern Period, which can be interpreted as a central historical fact of slavery and colonization. This section can be further subdivided into three large phases: (1) the expansion of European capital (1500,1814), (2) the Industrial Revolution (1815,1914), and (3) the Interwar Period (1914,1945). The final major period of diasporization can be considered a Contemporary or Late-modern phenomenon. It refers to the period immediately after World War II to the present day, specifying the case of the Hispanics in the United States as one key example. The paper outlines some aspects of the impact of the Latin American diaspora on the United States, from a socio-economic and politico-cultural point of view. While the Modern and Late-modern periods are undoubtedly the most critical for an understanding of diaspora in a modern, globalized context, for the purpose of this paper, more emphasis is placed on the latter period, which illustrates the progressive effect of globalization on the phenomenon of diasporization. The second period, the Modern Phase is not examined in this paper, as the focus is on a comparative analysis of the early Classical Period and the Contemporary or Late-modern Period. The incorporation of diaspora as a unit of analysis in the field of international relations has been largely neglected by both recent and critical scholarship on the subject matter. While a growing number of studies focus on the increasing phenomenon of diasporic communities, from the vantage of social sciences, the issue of diaspora appears to be inadequately addressed or ignored altogether. Certain key factors present themselves as limitations to the understanding of the concept, as well as its relevance to the field of international relations and the social sciences as a whole. This paper is meant to clarify some aspects of the definition of diaspora by critiquing the theories in the conventional literature, exposing the lacunae in terms of interpretation of diaspora and in the final analysis, establishing a historiography that may be useful in comparing certain features of "classical" diaspora and "contemporary" diaspora. The latter part of the paper is intended to provide illustrations of a contemporary diasporic community, using the example of Hispanics in the United States. [source] | ||||||||||||||||