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Newest Developments (newest + development)
Selected AbstractsPhotodiagnostic techniques for the endoscopic detection of premalignant gastrointestinal lesionsDIGESTIVE ENDOSCOPY, Issue 3 2003Ralph S. DaCosta Considerable attention is given to the clinical diagnosis of gastrointestinal (GI) malignancies as they remain the second leading cause of cancer-associated deaths in developed countries. Detection and intervention at an early stage of preneoplastic development significantly improve patient survival. High-risk assessment of asymptomatic patients is currently performed by strict endoscopic surveillance biopsy protocols aimed at early detection of dysplasia and malignancy. However, poor sensitivity associated with frequent surveillance programs incorporating conventional screening tools, such as white light endoscopy and multiple random biopsy, is a significant limitation. Recent advances in biomedical optics are illuminating new ways to detect premalignant lesions of the GI tract with endoscopy. The present review presents a summary report on the newest developments in modern GI endoscopy, which are based on novel optical endoscopic techniques: fluorescence endoscopic imaging and spectroscopy, Raman spectroscopy, light scattering spectroscopy, optical coherence tomography, chromoendoscopy, confocal fluorescence endoscopy and immunofluorescence endoscopy. Relying on the interaction of light with tissue, these ,state-of-the-art' techniques potentially offer an improved strategy for diagnosis of early mucosal lesions by facilitating targeted excisional biopsies. Furthermore, the prospects of real-time ,optical biopsy' and improved staging of lesions may significantly enhance the endoscopist's ability to detect subtle preneoplastic mucosal changes and lead to curative endoscopic ablation of these lesions. Such advancements within this specialty will be rewarded in the long term with improved patient survival and quality of life. [source] SWAT2000: current capabilities and research opportunities in applied watershed modellingHYDROLOGICAL PROCESSES, Issue 3 2005J. G. Arnold Abstract SWAT (Soil and Water Assessment Tool) is a conceptual, continuous time model that was developed in the early 1990s to assist water resource managers in assessing the impact of management and climate on water supplies and non-point source pollution in watersheds and large river basins. SWAT is the continuation of over 30 years of model development within the US Department of Agriculture's Agricultural Research Service and was developed to ,scale up' past field-scale models to large river basins. Model components include weather, hydrology, erosion/sedimentation, plant growth, nutrients, pesticides, agricultural management, stream routing and pond/reservoir routing. The latest version, SWAT2000, has several significant enhancements that include: bacteria transport routines; urban routines; Green and Ampt infiltration equation; improved weather generator; ability to read in daily solar radiation, relative humidity, wind speed and potential ET; Muskingum channel routing; and modified dormancy calculations for tropical areas. A complete set of model documentation for equations and algorithms, a user manual describing model inputs and outputs, and an ArcView interface manual are now complete for SWAT2000. The model has been recoded into Fortran 90 with a complete data dictionary, dynamic allocation of arrays and modular subroutines. Current research is focusing on bacteria, riparian zones, pothole topography, forest growth, channel downcutting and widening, and input uncertainty analysis. The model SWAT is meanwhile used in many countries all over the world. Recent developments in European Environmental Policy, such as the adoption of the European Water Framework directive in December 2000, demand tools for integrative river basin management. The model SWAT is applicable for this purpose. It is a flexible model that can be used under a wide range of different environmental conditions, as this special issue will show. The papers compiled here are the result of the first International SWAT Conference held in August 2001 in Rauischholzhausen, Germany. More than 50 participants from 14 countries discussed their modelling experiences with the model development team from the USA. Nineteen selected papers with issues reaching from the newest developments, the evaluation of river basin management, interdisciplinary approaches for river basin management, the impact of land use change, methodical aspects and models derived from SWAT are published in this special issue. Copyright © 2005 John Wiley & Sons, Ltd. [source] The history of sweet taste: not exactly a piece of cakeJOURNAL OF MOLECULAR RECOGNITION, Issue 3 2006Pierandrea Temussi Abstract Understanding the molecular bases of sweet taste is of crucial importance not only in biotechnology but also for its medical implications, since an increasing number of people is affected by food-related diseases like, diabetes, hyperlipemia, caries, that are more or less directly linked to the secondary effects of sugar intake. Despite the interest paid to the field, it is only through the recent identification and functional expression of the receptor for sweet taste that new perspectives have been opened, drastically changing our approach to the development of new sweeteners. We shall give an overview of the field starting from the early days up to discussing the newest developments. After a review of early models of the active site, the mechanisms of interaction of small and macromolecular sweet molecules will be examined in the light of accurate modeling of the sweet taste receptor. The analysis of the homology models of all possible dimers allowed by combinations of the human T1R2 and T1R3 sequences of the sweet receptor and the closed (A) and open (B) conformations of the mGluR1 glutamate receptor shows that only ,type B' sites, either T1R2(B) and T1R3(B), can host the majority of small molecular weight sweeteners. Simultaneous binding to the A and B sites is not possible with two large sweeteners but is possible with a small molecule in site A and a large one in site B. This observation accounted for the first time for the peculiar phenomenon of synergy between some sweeteners. In addition to these two sites, the models showed an external binding site that can host sweet proteins. Copyright © 2006 John Wiley & Sons, Ltd. [source] Prospective study of port wine stain treatment with dye laser: Comparison of two wavelengths (585 nm vs.LASERS IN SURGERY AND MEDICINE, Issue 2 2004595 nm), two pulse durations (0.5 milliseconds vs. Abstract Background and Objectives The conventional pulsed-dye laser (wavelength 585 nm, pulse duration 0.5 milliseconds) is seen as the standard treatment for port wine stains (PWS). Using the pulsed-dye laser at wavelengths of 590, 595, and 600 nm and at varying pulse durations of 1.5,40 milliseconds is one of the newest developments in the field, the therapeutic value of which has been examined in only a few studies. Treatment of PWS with short- and long-pulse dye lasers. Comparison of two wavelengths (585 nm vs. 595 nm) and two pulse durations (0.5 milliseconds vs. 20 milliseconds). Study Design/Materials and Methods Fifteen patients with untreated PWS were included in a randomized prospective study with three different laser settings. Patients underwent one treatment session. The following treatment parameters were chosen at a uniform spot size of 7 mm: (1) 585 nm/0.5 milliseconds/5.5 J/cm2, (2) 595 nm/0.5 milliseconds/5.5 J/cm2, and (3) 595 nm/20 milliseconds/13 J/cm2. The clearance as well as side effects was evaluated. All treatments were performed with cold air-cooling. Follow-up took place immediately, 2 days and 4 weeks after the treatment. The PWS was assigned a clearance score (CS) from 1 to 4 (1,=,poor to 4,=,excellent). Results Descriptively, 585 nm/0.5 milliseconds generated the best average CS of 2.7, followed by 595 nm/20 milliseconds (2.5) and 595 nm/0.5 milliseconds (1.6)); statistically, there is no difference between the CS of 585 nm/0.5 milliseconds and 595 nm/20 milliseconds. The best lightening rates overall were achieved in purple PWS (CS,=,3.5) versus red (CS,=,2.5) and pink (CS,=,2.0). Purple PWS responded best to 585 nm/0.5 milliseconds; red and pink PWS yielded similar results with 585 nm/0.5 milliseconds and 595 nm/20 milliseconds. The setting, 595 nm/0.5 milliseconds was clearly not as effective as the other laser settings. Purpura, pain, and crusting were most commonly reported after treatments with 585 nm/0.5 milliseconds (93%/93%/33%), closely followed by treatments at 595 nm/20 milliseconds (86%/93%/20%). The settings 595 nm/0.5 milliseconds yielded the lowest rate of adverse effects (67%/60%/0%). Hypopigmentation only occurred in one case (585 nm/0.5 milliseconds), and there were no reports of hyperpigmentation or scarring. Conclusions With respect to treating PWS, the conventional pulsed-dye laser set to 585 nm/0.5 milliseconds yields a significantly greater clearance rate than it does at a setting of 595 nm (with the same pulse duration, fluence, and spot size), although the former also entails the highest spectrum of adverse effects. In this study, purple PWS treated at these parameters showed the best results. In dealing with pink PWS, the results were similar to those of the conventional pulsed-dye laser when the pulse duration was increased to 20 milliseconds and fluence was increased. As a rule, the clearance rate corresponded to the extent of the postoperative purpura. Lasers Surg. Med. 34:168,173, 2004. © 2004 Wiley-Liss, Inc. [source] | ||||||||||