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Vital Importance (vital + importance)
Selected AbstractsEye gaze in virtual environments: evaluating the need and initial work on implementationCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 11 2009Norman Murray Abstract For efficient collaboration between participants, eye gaze is seen as being critical for interaction. Video conferencing either does not attempt to support eye gaze (e.g. AcessGrid) or only approximates it in round table conditions (e.g. life size telepresence). Immersive collaborative virtual environments represent remote participants through avatars that follow their tracked movements. By additionally tracking people's eyes and representing their movement on their avatars, the line of gaze can be faithfully reproduced, as opposed to approximated. This paper presents the results of initial work that tested if the focus of gaze could be more accurately gauged if tracked eye movement was added to that of the head of an avatar observed in an immersive VE. An experiment was conducted to assess the difference between user's abilities to judge what objects an avatar is looking at with only head movements being displayed, while the eyes remained static, and with eye gaze and head movement information being displayed. The results from the experiment show that eye gaze is of vital importance to the subjects correctly identifying what a person is looking at in an immersive virtual environment. This is followed by a description of the work that is now being undertaken following the positive results from the experiment. We discuss the integration of an eye tracker more suitable for immersive mobile use and the software and techniques that were developed to integrate the user's real-world eye movements into calibrated eye gaze in an immersive virtual world. This is to be used in the creation of an immersive collaborative virtual environment supporting eye gaze and its ongoing experiments. Copyright © 2009 John Wiley & Sons, Ltd. [source] Applications of PAT-Process Analytical Technology in Recombinant Protein Processes with Escherichia coliENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 2 2008C. Kaiser Abstract Monitoring of bioprocesses and thus observation and identification of such processes is one of the main aims of bioprocess engineering. It is of vital importance in bioprocess development to improve the overall productivity by avoiding unintentional limitations to ensure not only optimal process conditions but also the observation of established production processes. Furthermore, reproducibility needs to be improved and final product quality and quantity be guaranteed. Therefore, an advanced monitoring and control system has been developed, which is based on different in-line, on-line and at-line measurements for substrates and products. Observation of cell viability applying in-line radio frequency impedance measurement and on-line determination of intracellular recombinant target protein using the reporter protein T-Sapphire GFP based on in-line fluorescence measurement show the ability for the detection of critical process states. In this way, the possibility for the on-line recognition of optimal harvest times arises and disturbances in the scheduled process route can be perceived. [source] A review on the interactions between gut microbiota and innate immunity of fishFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2008Geovanny D. Gómez Abstract Although fish immunology has progressed in the last few years, the contribution of the normal endogenous microbiota to the overall health status has been so far underestimated. In this context, the establishment of a normal or protective microbiota constitutes a key component to maintain good health, through competitive exclusion mechanisms, and has implications for the development and maturation of the immune system. The normal microbiota influences the innate immune system, which is of vital importance for the disease resistance of fish and is divided into physical barriers, humoral and cellular components. Innate humoral parameters include antimicrobial peptides, lysozyme, complement components, transferrin, pentraxins, lectins, antiproteases and natural antibodies, whereas nonspecific cytotoxic cells and phagocytes (monocytes/macrophages and neutrophils) constitute innate cellular immune effectors. Cytokines are an integral component of the adaptive and innate immune response, particularly IL-1,, interferon, tumor necrosis factor-,, transforming growth factor-, and several chemokines regulate innate immunity. This review covers the innate immune mechanisms of protection against pathogens, in relation with the installation and composition of the normal endogenous microbiota in fish and its role on health. Knowledge of such interaction may offer novel and useful means designing adequate therapeutic strategies for disease prevention and treatment. [source] Land use change and the dependence of national priority species on protected areasGLOBAL CHANGE BIOLOGY, Issue 9 2008SARAH F. JACKSON Abstract The establishment and maintenance of a system of protected areas is central to regional and global strategies for the conservation of biodiversity. The current global trend towards human population growth and widespread environmental degradation means that such areas are becoming increasingly isolated, fragmented habitat islands. In regions in which this process is well advanced, a high proportion of species are thus predicted to have become restricted to protected areas. Here, using uniquely detailed datasets for Britain, a region with close to the global level of percentage coverage by statutory protected areas, we determine the extent of restriction of species of conservation concern to these areas. On the basis of currently known distributions, more than a half of such species are highly dependent on protected areas for their continued persistence, occurring either entirely or largely within their bounds. Such coverage is of particular importance for those species with narrower distributions, and therefore, under the greatest threats, underlining the vital importance of adequately resourcing, maintaining, and developing protected areas to prevent these species from being lost. [source] Communication and Contention: The Role of Literacy in Conflicts with ,Abb,sid OfficialsHISTORY COMPASS (ELECTRONIC), Issue 5 2007Maaike Van Berkel ,Abb,sid officials of the late ninth and early tenth centuries operated in a highly bureaucratized and literate environment and they expressed their identity in terms of expertise in writing. However, in their daily business they had to communicate with all kinds of social groups, some of which had not , or only to a certain level , been introduced to writing. During the last three decades a series of groundbreaking studies appeared on the introduction and dissemination of writing in Medieval Europe. The role of literacy in Arab and Islamic societies in this period have as yet received very little, and mainly rather specialized, attention. The communication between ,Abb,sid officials and other social groups will be studied in cases of conflict and their settlements. Conflict settlement is also a field of research that recently witnessed important new insights. Studying the use of written documents in dispute settlements , a situation in which communication is of vital importance to all parties involved , forms therefore an excellent opportunity to analyse familiarity with, and confidence in, writing among the various groups within the ,Abb,sid caliphate. [source] Exploring alternative relationships between perceived investment in employee development, perceived supervisor support and employee outcomesHUMAN RESOURCE MANAGEMENT JOURNAL, Issue 2 2010Bård Kuvaas The purpose of this study was to explore alternative relationships between perceived investment in employee development (PIED), perceived supervisor support (PSS), and employee outcomes in the form of attitudes (affective commitment and turnover intention) and work performance (work effort, work quality and organisational citizenship behaviour). A cross-sectional survey among 331 employees from a Norwegian telecommunications organisation showed that the relationship between PSS and employee attitudes was partially mediated by PIED. In addition, PSS was found to moderate the relationship between PIED and three self-report measures of work performance. The form of the moderation revealed a positive relationship only for high levels of PSS. These findings suggest that line managers are of vital importance in implementing developmental HR practices, either because they influence how such practices are perceived by employees, which, in turn, affects employee attitudes, or because positive experiences with both line managers and HR practices seem to be needed in order for developmental HR practices to positively influence employee performance. [source] An unconditionally stable three level finite difference scheme for solving parabolic two-step micro heat transport equations in a three-dimensional double-layered thin filmINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 4 2004Weizhong Dai Abstract Heat transport at the microscale is of vital importance in microtechnology applications. The heat transport equations are parabolic two-step equations, which are different from the traditional heat diffusion equation. In this study, we develop a three-level finite difference scheme for solving the micro heat transport equations in a three-dimensional double-layered thin film. It is shown by the discrete energy method that the scheme is unconditionally stable. Numerical results for thermal analysis of a gold layer on a chromium padding layer are obtained. Copyright © 2003 John Wiley & Sons, Ltd. [source] Discrete-time Lyapunov stable-staggered estimator MIMO adaptive interference cancelation with experimental verificationINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 4 2010Jawad Arif Abstract Adaptive interference cancelation is of vital importance in a broad array of scientific and engineering disciplines. In this paper we develop a closed-loop discrete-time interference cancelation algorithm. The novel features of this algorithm are its ability to deal with multiple channels being affected by interferences with different frequency spectrums. Also we provide a proof of Lyapunov stability of closed-loop system and asymptotically perfect interference cancelation for a class of interference signals. Furthermore, we introduce a new approach for updating the estimator through the use of staggered estimate. The goal of staggered estimation is to minimize the total number of estimates/calculations done within a time period while ensuring that there is no estimator aliasing. Finally, the proposed algorithm is implemented on an TMS320C6713 DSP Kit and an experimental verification is obtained. Copyright © 2009 John Wiley & Sons, Ltd. [source] Metallurgical characterization, galvanic corrosion, and ionic release of orthodontic brackets coupled with Ni-Ti archwiresJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2007Myrsini S. Darabara Abstract In orthodontics, a combination of metallic alloys is placed into the oral cavity during medical treatment and thus the corrosion resistance and ionic release of these appliances is of vital importance. The aim of this study is to investigate the elemental composition, microstructure, hardness, corrosion properties, and ionic release of commercially available orthodontic brackets and Copper Ni-Ti archwires. Following the assessment of the elemental composition of the orthodontic wire (Copper Ni-TiÔ) and the six different brackets (Micro Loc, Equilibrium, OptiMESHXRT, Gemini, Orthos2, and Rematitan), cyclic polarization curves were obtained for each material to estimate the susceptibility of each alloy to pitting corrosion in 1M lactic acid. Galvanic corrosion between the orthodontic wire and each bracket took place in 1M lactic acid for 28 days at 37°C and then the ionic concentration of Nickel and Chromium was studied. The orthodontic wire is made up from a Ni-Ti alloy with copper additions, while the orthodontic brackets are manufactured by different stainless steel grades or titanium alloys. All tested wires and brackets with the exception of Gemini are not susceptible to pitting corrosion. In galvanic corrosion, following exposure for 28 days, the lowest potential difference (,250 mV) appears for the orthodontic wire Copper Ni-Ti and the bracket made up from pure titanium (Rematitan) or from the stainless steel AISI 316 grade (Micro Loc). Following completion of the galvanic corrosion experiments, measurable quantities of chromium and nickel ions were found in the residual lactic acid solution. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [source] EVALUATION OF THE CONTROLS ON FRACTURING IN RESERVOIR ROCKSJOURNAL OF PETROLEUM GEOLOGY, Issue 4 2005D.C.P. Peacock The style, geometry and distribution of fractures within reservoir rocks can be controlled by numerous factors, including: rock characteristics and diagenesis (lithology, sedimentary structures, bed thickness, mechanical stratigraphy, the mechanics of bedding planes); structural geology (tectonic setting, palaeostresses, subsidence and uplift history, proximity to faults, position in a fold, timing of structural events, mineralisation, the angle between bedding and fractures); and present-day factors, such as orientations of in situ stresses, fluid pressure, perturbation of in situ stresses and depth. The relative timing of events plays a crucial role in determining the geometry and distribution of fractures. For example, open fractures are commonly clustered around faults if the open fractures and faults formed at the same time, but clustering does not tend to occur if the open fractures pre-date or post-date the faults. Understanding these factors requires traditional geological skills, including the analysis of one-dimensional (line-sampling) data from core, borehole images and exposed analogues. This paper reviews the factors that control fractures within reservoir rocks and discusses methods to assess those controls. Examples are presented from Mesozoic limestones in southern England. It is shown that traditional geological skills are of vital importance in determining the rock characteristics, structural and present-day factors that control fractures. [source] Organizational Dynamic Capability and Innovation: An Empirical Examination of Internet FirmsJOURNAL OF SMALL BUSINESS MANAGEMENT, Issue 3 2009Jianwen (Jon) Liao This paper extends the dynamic capability perspective into the study of innovation by entrepreneurial firms. Drawing from both the resource-based view and the dynamic capability perspective, this paper explores theoretically and examines empirically the different roles played by a firm's resource stock (endowment of resources and capabilities) and its integrative capabilities (ability to recognize opportunities as well as to configure and deploy resources) in the process of firm innovation. Our structural equation modeling results, based on a sample of 120 Internet-based companies, indicate that both the firm's resource stock and integrative capabilities affect its innovation. Additionally, we also found that the relationship between resource stock and innovation is mediated by integrative capabilities. That is, merely possessing well-endowed resource stock per se is not sufficient for innovation. Thus, it is the firm's ability to mobilize its resources and capabilities and align them dynamically with the changing opportunities in the environment that is of vital importance as the firm constantly innovates to survive and create its own competitive advantage. In the hypercompetitive and fast changing Internet-based environment, such a need for dynamic capabilities is especially accentuated. Implications and suggestions for future research are provided. [source] Wet clutch transmission fluid for AWD differentials: base fluid influence on friction characteristicsLUBRICATION SCIENCE, Issue 1 2006Rikard Mäki Abstract During the past few years several electronically controllable automotive transmission systems, where wet clutches are used as intelligent differentials, have emerged in the market. In this type of application the anti-shudder properties of the lubricants are of vital importance. This paper investigates the influence of base fluids on the anti-shudder properties of transmission fluids for wet clutches in all-wheel-drive systems. The investigated all-wheel-drive system featuring a wet multi-plate clutch with a sintered brass-based friction material is described. The test equipment used to determine the frictional characteristics of the transmission fluid is described. The parameters studied include base fluid type and base fluid viscosity. It is shown that the choice of base fluid has no impact on torque capacity, but that the base fluid influences the temperature dependence of the dynamic friction and the anti-shudder properties. It is also shown that the major effect on the friction characteristics is caused by additive effects rather than base fluid effects. Copyright © 2006 John Wiley & Sons, Ltd. [source] An economical difference scheme for heat transport equation at the microscale,NUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS, Issue 6 2004Zhiyue Zhang Abstract Heat transport at the microscale is of vital importance in microtechnology applications. In this article, we proposed a new ADI difference scheme of the Crank-Nicholson type for heat transport equation at the microscale. It is shown that the scheme is second order accurate in time and in space in the H1 norm. Numerical result implies that the theoretical analysis is correct and the scheme is effective. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2004 [source] A convergent three-level finite difference scheme for solving a dual-phase-lagging heat transport equation in spherical coordinatesNUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS, Issue 1 2004Weizhong Dai Abstract Heat transport at the microscale is of vital importance in microtechnology applications. The heat transport equation is different from the traditional heat diffusion equation since a second-order derivative of temperature with respect to time and a third-order mixed derivative of temperature with respect to space and time are introduced. In this study, we consider the heat transport equation in spherical coordinates and develop a three-level finite difference scheme for solving the heat transport equation in a microsphere. It is shown that the scheme is convergent, which implies that the scheme is unconditionally stable. Results show that the numerical solution converges to the exact solution. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 20: 60,71, 2004. [source] Biography Matters: Carol Shields, Mary Swann, A. S. Byatt, Possession, Deborah Crombie, Dreaming of the BonesORBIS LITERARUM, Issue 5 2003Heidi Hansson The interest in life writing in recent years has led to an awareness of the close connections between biographical and fictional writing, which in turn has made the art of biography an important theme in contemporary fiction influenced by feminism, New Historicism and poststructuralism. The main issue in works like A. S. Byatt's Possession, Carol Shields's Mary Swann and Deborah Crombie's Dreaming of the Bones is to what extent a biography can be trusted to tell the truth of someone's life, and how far it is compromised by the biographer's motives. Works like these can be said to stand in a metaphorical relationship to the genre of biography, drawing attention to the epistemological problems of biography-writing by emphasising the slippage between fiction and biography. Yet, while these novels continually question the veracity of biographical evidence, they also make clear that biography is of vital importance for our understanding of literature. [source] Silica nanoparticle addition to control the calcium-leaching in cement-based materialsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 6 2006J. J. Gaitero Abstract The calcium leaching of the cement hydrated matrix is of vital importance for constructions like water containers, dams, bridges, etc which have to be in contact with water during their lifetime. The aim of this work is the study of the reduction of such a negative phenomenon by the addition of silica nanoparticles. Several characterisation techniques such as 29Si MAS NMR, X-ray diffraction, mercury intrusion porosimetry and EDX-microanalysis have been used to evaluate the effect of the nanoparticles in the cement matrix nanostructure and in their impact on the evolution of the Ca leaching throughout time. Subsequent analysis of the results indicates that silica nanoparticles can reduce the Ca-leaching both decreasing the amount of portlandite in the matrix and controlling the degradation rate of the C,S,H gel. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Photosynthetic biomass and H2 production by green algae: from bioengineering to bioreactor scale-upPHYSIOLOGIA PLANTARUM, Issue 1 2007Ben Hankamer The development of clean borderless fuels is of vital importance to human and environmental health and global prosperity. Currently, fuels make up approximately 67% of the global energy market (total market = 15 TW year,1) (Hoffert et al. 1998). In contrast, global electricity demand accounts for only 33% (Hoffert et al. 1998). Yet, despite the importance of fuels, almost all CO2 free energy production systems under development are designed to drive electricity generation (e.g. clean-coal technology, nuclear, photovoltaic, wind, geothermal, wave and hydroelectric). In contrast, and indeed almost uniquely, biofuels also target the much larger fuel market and so in the future will play an increasingly important role in maintaining energy security (Lal 2005). Currently, the main biofuels that are at varying stages of development include bio-ethanol, liquid carbohydrates [e.g. biodiesel or biomass to liquid (BTL) products], biomethane and bio-H2. This review is focused on placing bio-H2 production processes into the context of the current biofuels market and summarizing advances made both at the level of bioengineering and bioreactor design. [source] From experience: applying the risk diagnosing methodologyTHE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 3 2002Jimme A. Keizera No risk, no reward. Companies must take risks to launch new products speedily and successfully. The ability to diagnose and manage risks is increasingly considered of vital importance in high-risk innovation. This article presents the Risk Diagnosing Methodology (RDM), which aims to identify and evaluate technological, organizational and business risks in product innovation. RDM was initiated, developed and tested within a division of Philips Electronics, a multinational company in the audio, video and lighting industry. On the basis of the results the senior Vice President (R&D) of Philips Lighting decided to include the method in the company's standard innovation procedures. Since then, RDM has been applied on product innovation projects in areas as diverse as automobile tires, ship propellers, printing equipment, landing gear systems and fast-moving consumer goods such as shampoo, margarine and detergents. In this article we will describe how Unilever, one of the world's leading companies in fast-moving consumer goods, adopted RDM after a major project failure in the midnineties. At Unilever, RDM proved very useful in diagnosing project risks, promoting creative solutions for diagnosed risks and strengthening team ownership of the project as a whole. Our results also show that RDM outcomes can be used to build a knowledge base of potential risks in product innovation projects. [source] Auctions Versus Beauty Contests: The Allocation of UMTS Licences in EuropeANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 1 2003L. Cartelier The deployment of the so-called UMTS 3rd generation mobile networks is a step of vital importance for the promotion of competition in the telecommunications sector. The provision of high-traffic services presupposes that operators have access to the hertzian spectrum. The hertzian spectrum is a natural resource whose scarcity derives from the fact that only part of it is usable, for both technical and economic reasons. While the resource was sufficient to meet users' needs, the hertzian spectrum was allocated for little or no charge, on the principle of ,first come, first served'. However, with the explosion of technical progress in transmission technologies, new applications and new forms of use appeared, leading to a drastic increase in potential demand. It is in this context that the idea of charging for use of the spectrum arose, so as to discourage uneconomical use of the resource (e.g. stockpiling, wastage), to ensure a fair allocation between competing users and to forestall congestion. The purpose of this paper is first to examine the procedures for the allocation of hertzian spectrum operating licences, from the points of view of efficiency, transparency and sharing of the surplus. We shall then compare the results from the two approaches that were actually used in Europe: the open ascending auction and the beauty contest, before turning our attention to new forms of public action that result from the process of liberalization. [source] Hyperaccumulation of selenium in hybrid striped bass: a functional food for aquaculture?AQUACULTURE NUTRITION, Issue 3 2008P.A. COTTER Abstract One method of increasing the value of aquacultured product is to produce fillets that are fortified with minerals that are beneficial to human health , that is enhance the functionality of an already healthy product. A good candidate mineral in this regard is selenium (Se) which is of vital importance to normal metabolism in humans. In order to evaluate the dose response and tissue accumulation of supplemental dietary Se, a study was undertaken with hybrid striped bass (HSB). Animals were fed diets supplemented with either organic (0,3.2 mg kg,1 as SelPlex®) or inorganic (0.2 and 0.4 mg kg,1 as sodium selenite) Se for 6 weeks. Because basal fishmeal-based diets contained 1.22 mg Se kg,1, doses of Se delivered equated to 1.22,4.42 mg kg,1. At trial end, greatest weight gain was observed in fish receiving 0.2 mg Se kg,1, irrespective of form (organic/inorganic). Se accumulation in HSB liver and fillet revealed a classical dose-response once a threshold level of 0.2 mg Se kg,1 was surpassed. Greatest tissue accumulation of Se was observed in fish fed the 3.2 mg Se kg,1 level (P > 0.0001). A 100 g portion of Se-enhanced HSB fillet would contain between 33 and 109 ,g Se, amounting to a dietary intake of between 25 and 80 ,g Se; a level that would satisfy present daily intake recommendations. Comparison of tissue Se levels indicated that the muscle provides a more conspicuous gauge of dietary Se dose-response than does liver. Dietary treatments of between 0.4 and 1.6 mg organic Se kg,1 reduced (P < 0.024) plasma glutathione peroxidase (GSH-Px) activity. No differences were observed in ceruloplasmin, lysozyme or GSH-Px activities between organic and inorganic Se when delivered at the 0.2 mg Se kg,1 level. Ceruloplasmin, lysozyme and GSH-Px levels were elevated (P , 0.025) in fish fed the diet containing 0.4 mg inorganic Se kg,1. [source] Cutaneous embolization of cardiac myxomaBRITISH JOURNAL OF DERMATOLOGY, Issue 2 2002M.J. García-F-Villalta Summary Atrial myxoma is the most common primary tumour of the heart. Skin manifestations in patients with a cardiac myxoma are frequent and may be due to cutaneous emboli, or may be specific findings as part of more complex syndromes. We present a 33-year-old-man with a history of episodes of pain in both legs and an ischaemic neurological event, who also had episodes of acral papular erythematous lesions on the legs and feet including the soles. The histological finding of dermal vessels occluded by a myxomatous material was the clue to the diagnosis of a cardiac myxoma. The diagnosis of this entity can be very difficult, because of the broad spectrum of clinical features; rarely the skin manifestations lead to the diagnosis of this tumour. The histological recognition of the myxomatous emboli is of vital importance for the diagnosis and treatment of this disease. [source] Large-scale Migration of Fluids toward Foreland Basins during Collisional Orogeny: Evidence from Triassic Anhydrock Sequences and Regional Alteration in the Middle-Lower Yangtze AreaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 1 2004HOU Zengqian Abstract The middle-lower Yangtze area underwent a series of complex tectonic evolution, such as Hercynian extensional rifting, Indosinian foreland basining, and Yanshanian transpression-transtension, resulting in a large distinctive Cu-Fe-Au metallogenic belt. In the tectonic evolution, large-scale migration and convergence of fluids toward foreland basins induced during the collisional orogeny of the Yangtze and North China continental blocks were of vital importance for the formation of the metallogenic belt. Through geological surveys of the middle-lower Yangtze area, three lines of evidence of large-scale fluid migration are proposed: (1) The extensive dolomitic and silicic alteration penetrating Cambrian-Triassic strata generally occurs in a region sandwiched between the metallogenic belt along the Yangtze River and the Dabie orogenic belt, and in the alteration domain alternately strong and weak alteration zones extend in a NW direction and are controlled by the fault system of the Dabie orogenic belt; it might record the locus of the activities of long-distance migrating fluids. (2) The textures and structures of very thick Middle-Lower Triassic anhydrock sequences in restricted basins along the river reveal the important contribution of the convergence of regional hot brine in restricted basins and the chemical deposition or their formation. (3) Early-Middle Triassic syndepositional iron carbonate sequences and Fe-Cu-Pb-Zn massive sulfide deposits alternate with anhydrock sequences or are separated from the latter, but all of them occur in the same stratigraphic horizon and are intimately associated with each other, being the product of syndeposition of high-salinity hot brine. According to the geological surveys, combined with previous data, the authors propose a conceptual model of fluid migration-convergence and mineralization during the Dabie collisional orogeny. [source] Resuscitating the Microcirculation in Sepsis: The Central Role of Nitric Oxide, Emerging Concepts for Novel Therapies, and Challenges for Clinical TrialsACADEMIC EMERGENCY MEDICINE, Issue 5 2008Stephen Trzeciak MD Abstract Microcirculatory dysfunction is a critical element of the pathogenesis of severe sepsis and septic shock. In this Bench-to-Bedside review, we present: 1) the central role of the microcirculation in the pathophysiology of sepsis; 2) new translational research techniques of in vivo video microscopy for assessment of microcirculatory flow in human subjects; 3) clinical investigations that reported associations between microcirculatory dysfunction and outcome in septic patients; 4) the potential role of novel agents to "rescue" the microcirculation in sepsis; 5) current challenges facing this emerging field of clinical investigation; and 6) a framework for the design of future clinical trials aimed to determine the impact of novel agents on microcirculatory flow and organ failure in patients with sepsis. We specifically focus this review on the central role and vital importance of the nitric oxide (NO) molecule in maintaining microcirculatory homeostasis and patency, especially when the microcirculation sustains an insult (as with sepsis). We also present the scientific rationale for clinical trials of exogenous NO administration to treat microcirculatory dysfunction and augment microcirculatory blood flow in early sepsis therapy. [source] What factors affect lymph node yield in surgery for rectal cancer?COLORECTAL DISEASE, Issue 5 2004C. C. Thorn Abstract Objective The detection of lymph node metastases is of vital importance in patients undergoing excisional surgery for rectal cancer as it provides important prognostic information and facilitates decision-making with regards to adjuvant therapy. It has been suggested that patients in whom only a small number of nodes are present in the excised specimen have a worse prognosis, presumably due to inadequate lymphadenectomy and consequent understaging of the disease. The aim of this study was to determine which factors affect the yield of lymph nodes. Methods This was a retrospective study of patients who had undergone a resection for histologically proven adenocarcinoma of the rectum. The total number of lymph nodes identified in the excised specimen was recorded in each case. A multivariate analysis was performed to ascertain whether this number was significantly influenced by any of several variables. Results A total of 167 patients were studied (M:F ratio 107 : 60, median age 70 years). The median number of lymph nodes contained within the resected specimen was 16 (interquartile range 10,21). On univariate analysis a significantly higher yield of lymph nodes was obtained with tumours in the middle third of the rectum (P = 0.007), larger tumours (P < 0.001), more locally advanced tumours according to both pT staging (P = 0.001) and Dukes' staging (P = 0.020), an increased number of involved nodes (P = 0.003) and examination by a specialist histopathologist (P = 0.003). On multivariate analysis the only significant variables were tumour size (P = 0.021), number of positive nodes (P = 0.007) and histopathologist (P = 0.021). Conclusions The number of lymph nodes identified within the excised specimen in patients undergoing resection of a rectal cancer positively correlates with the size of the tumour and is also dependent on the examining histopathologist. In addition, in node-positive patients the number of involved nodes increases with increasing lymph node yield. [source] | |||||||||||||||||||||||||