Cost Advantage (cost + advantage)

Distribution by Scientific Domains
Distribution within Business, Economics, Finance and Accounting


Selected Abstracts


Safety, Efficacy, and Cost Advantages of Combined Coronary Angiography and Angioplasty

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 3 2003
CLAUDE LE FEUVRE M.D., F.E.S.C.
Aim: The safety and efficacy of ad hoc PTCA has been previously reported and this approach is performed in many angioplasty centers as a routine procedure. The aim of this study is to examine whether this approach reduces the length, and cost of hospital stay. Methods and results: To determine the hospital costs we studied 2,440 PTCAs over 11 years in our institution (1990,2000). Urgent PTCA for acute coronary syndromes refractory to medical treatment were excluded. In 1809 patients (74%) angioplasty was performed immediately after coronary angiography, while separate procedures were performed in 631 patients. Indication for PTCA was unstable angina in 1342 patients (55%). In the ad hoc PTCA group, 92% of the culprit lesions were successfully treated; complications included myocardial infarction (2%), urgent bypass surgery (0.6%) and death (0.9%). The rate of combined procedure progressively increased from 54% in 1990 to 88% in 2000, with a significant decrease in the rate of complications. After adjusting for clinical and angiographic differences between combined and separate procedures, angiographic success and complication rates were not statistically different in the two groups. Mean length of hospital stay decreased all along the years, and was 45% less in the ad hoc PTCA group (11.4 ± 6.9vs18.2 ± 7.7in 1990,5.4 ± 4.3vs10.8 ± 5.7in 2000,P < 0.0001). The cost was 40% lower in the ad hoc PTCA group. For patients with stable angina, the savings were 49%, and for those with unstable angina, they were 29%. Conclusion: In the era of coronary stenting, ad hoc PTCA can be performed in most of the patients as safely and successfully as a separate procedure. It reduces the length, and the cost of hospital stay in patients with stable or unstable angina. (J Interven Cardiol 2003;16:195,199) [source]


Tuning the Refractive Index of Polymers for Polymer Waveguides Using Nanoscaled Ceramics or Organic Dyes,

ADVANCED ENGINEERING MATERIALS, Issue 1-2 2004
J. Böhm
Plastic Optical Fibers (POF) show advantageous properties like high flexibility and their cost advantage in comparison to glass fibers. The refractive indices of core and cladding have to be modified in order to get total reflectance. Thus, there is a strong demand for refractive index adjustable polymers with improved transmission properties in the visible and the NIR range. Inorganic nanosized particles or organic dyes homogeniously dispersed or solved in the polymer matrix allow a tailored increase or decrease of the refractive index of various polymers. [source]


Nitrate Removal Rates in a 15-Year-Old Permeable Reactive Barrier Treating Septic System Nitrate

GROUND WATER MONITORING & REMEDIATION, Issue 3 2008
W.D. Robertson
Permeable reactive barriers (PRBs) have gained popularity in recent years as a low-cost method for ground water remediation. However, their cost advantage usually requires that these barriers remain maintenance free for a number of years after installation. In this study, sediment cores were retrieved from a pilot-scale PRB consisting of a sand and wood particle (sawdust) mixture that has been in continuous operation for 15 years treating nitrate from a septic system plume in southern Ontario (Long Point site). Reaction rates for the 15-year-old media were measured in dynamic flow column tests and were compared to rates measured in year 1 using the same reactive mixture. Nitrate removal rates in the 15-year-old media varied, as expected, with temperature in the range of 0.22 to 1.1 mg N/L/d at 6 °C to 10 °C to 3.5 to 6.0 mg N/L/d at 20 °C to 22 °C. The latter rates remained within about 50% of the year 1 rates (10.2 ± 2.7 mg N/L/d at 22 °C). Near the end of the year 15 column test, media particles >0.5 mm in diameter, containing most of the wood particles, were removed from the reactive media by sieving. Nitrate removal subsequently declined by about 80%, indicating that the wood particles were the principal energy source for denitrification. This example shows that some denitrifying PRBs can remain maintenance free and be adequately reactive for decades. [source]


Aminoglycoside dosing in diabetes

JOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 2 2000
Axworthy
Studies have evaluated the comparative efficacy, toxicity and costs associated with extended-interval vs. standard multiple daily dosing of aminoglycosides. In this case, an elderly man with diabetes and good renal function at baseline was switched from standard to extended-interval dosing. During the course of therapy there was evidence of decreased renal function. Pertinent literature was searched for, uncovered and critically evaluated to determine if and what evidence supports using extended dosing of aminoglycosides in this population. No data were found specifically evaluating the different dosing strategies in diabetic patients. However, there were many trials and several meta-analysis located that compared the two dosing strategies, most suggesting at least a cost advantage and possibly less toxicity with extended-interval dosing. Further information is needed to determine whether there is a differential risk for toxicity between these dosing regimens in patient with diabetes. [source]


Strategic Quality Decisions under Heterogeneous Resource Endowments

JOURNAL OF ECONOMICS & MANAGEMENT STRATEGY, Issue 2 2001
Byong-Duk Rhee
The literature on product competition advocates a differentiation strategy assuming firm homogeneity in resources. However, firm heterogeneity in resource endowments has long been recognized in economics. Merging these two perspectives, we show that the increase in consumer preference for quality leads to firms' aggressive price competition instead of quality differentiation. As consumers look for higher quality, the cost advantage arising from superior resources increases and makes head-to-head competition more profitable than accommodating a less efficient rival. When consumers are highly concerned about quality, even a small resource difference leads a more efficient firm to initiate cutthroat price competition for market dominance. [source]


Resource Utilization, Cost, and Health Status Impacts of Coronary Stent Versus "Optimal" Percutaneous Coronary Angioplasty: Results from the OPUS-I Trial

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 4 2002
NANCY NEIL Ph.D.
In the OPUS-I trial, primary coronary stent implantation reduced 6-month composite incidence of death, myocardial infarction, cardiac surgery, or target vessel revascularization relative to a strategy of initial PTCA with provisional s tenting inpatients undergoing single vessel coronary angioplasty. The purpose of this research was to compare the economic and health status impacts of each treatment strategy. Resource utilization data were collected for the 479 patients randomized in OPUS-I. Itemized cost estimates were derived from primary hospital charge data gathered in previous multicenter trials evaluating coronary stents, and adjusted to approximate 1997 Medicare-based costs for a cardiac population. Health status at 6 months was assessed using the Seattle Angina Questionnaire (SAQ). Initial procedure related costs for patients treated with a primary stent strategy were higher than those treated with optimal PTCA/provisional stent ($5,389 vs $4,339, P<0.001). Costs of initial hospitalization were also higher for patients in the primary stent group ($9,234 vs $8,434, P<0.01) chiefly because of the cost differences in the index revascularization. Mean 6-month costs were similar in the two groups; however, there was a slight cost advantage associated with primary stenting. Bootstrap replication of 6-month cost data sustained the economic attractiveness of the primary stent strategy. There were no differences in SAQ scores between treatment groups. In patients undergoing single vessel coronary angioplasty, routine stent implantation improves important clinical outcomes at comparable, or even reduced cost, compared to a strategy of initial balloon angioplasty with provisional stenting. [source]


Economies of scale after deregulation in LTL trucking: a test case for the survivor technique

MANAGERIAL AND DECISION ECONOMICS, Issue 4 2008
James N. GiordanoArticle first published online: 4 MAR 200
Early critics of motor carrier deregulation believed that the policy was unwise because strong economies of scale would lead to harmful market concentration, particularly in the industry's LTL segment. Using two methodologies, the survivor technique and the trans-log cost function, this study finds that economies of scale do extend across the entire spectrum of firm sizes in LTL trucking. Long-run average cost appears to decline mildly and at a diminishing rate with increases in firm size, however, such that any cost advantage for larger firms has been insufficient to eliminate new entry and competition from smaller rivals. As a result, after the first 20 years of deregulation, the corresponding increase in market concentration has also been mild. Moreover, the consistency of results from the two methodologies gives credibility to the survivor technique as an empirical method of identifying economies of scale. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Cost-comparison of DDT and alternative insecticides for malaria control

MEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2000
K. Walker
Summary In anti-malaria operations the use of DDT for indoor residual spraying has declined substantially over the past 30 years, but this insecticide is still considered valuable for malaria control, mainly because of its low cost relative to alternative insecticides. Despite the development of resistance to DDT in some populations of malaria vector Anopheles mosquitoes (Diptera: Culicidae), DDT remains generally effective when used for house-spraying against most species of Anopheles, due to excitorepellency as well as insecticidal effects. A 1990 cost comparison by the World Health Organization (WHO) found DDT to be considerably less expensive than other insecticides, which cost 2 to 23 times more on the basis of cost per house per 6 months of control. To determine whether such a cost advantage still prevails for DDT, this paper compares recent price quotes from manufacturers and WHO suppliers for DDT and appropriate formulations of nine other insecticides (two carbamates, two organophosphates and five pyrethroids) commonly used for residual house-spraying in malaria control programmes. Based on these ,global' price quotes, detailed calculations show that DDT is still the least expensive insecticide on a cost per house basis, although the price appears to be rising as DDT production declines. At the same time, the prices of pyrethroids are declining, making some only slightly more expensive than DDT at low application dosages. Other costs, including operations (labour), transportation and human safety may also increase the price advantages of DDT and some pyrethroids vs. organophosphates and carbamates, although possible environmental impacts from DDT remain a concern. However, a global cost comparison may not realistically reflect local costs or effective application dosages at the country level. Recent data on insecticide prices paid by the health ministries of individual countries showed that prices of particular insecticides can vary substantially in the open market. Therefore, the most cost-effective insecticide in any given country or region must be determined on a case-by-case basis. Regional coordination of procurement of public health insecticides could improve access to affordable products. [source]


Performance and cost analysis of future, commercially mature gasification-based electric power generation from switchgrass

BIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 2 2009
Haiming Jin
Abstract Detailed process designs and mass/energy balances are developed using a consistent modeling framework and input parameter assumptions for biomass-based power generation at large scale (4536 dry metric tonnes per day switchgrass input), assuming future commercially mature component equipment performance levels. The simulated systems include two gasification-based gas turbine combined cycles (B-IGCC) designed around different gasifier technologies, one gasification-based solid oxide fuel cell cycle (B-IGSOFC), and a steam-Rankine cycle. The simulated design-point efficiency of the B-IGSOFC is the highest among all systems (51.8%, LHV basis), with modestly lower efficiencies for the B-IGCC design using a pressurized, oxygen-blown gasifier (49.5% LHV) and for the B-IGCC design using a low-pressure indirectly heated gasifier (48.6%, LHV). The steam-Rankine system has a simulated efficiency of 33.0% (LHV). Detailed capital costs are estimated assuming commercially mature (,Nth plant') technologies for the two B-IGCC and the steam-Rankine systems. B-IGCC systems are more capital-intensive than the steam-Rankine system, but discounted cash flow rate of return calculations highlight the total cost advantage of the B-IGCC systems when biomass prices are higher. Uncertainties regarding prospective mature-technology costs for solid oxide fuel cells and hot gas sulfur clean-up technologies assumed for the B-IGSOFC performance analysis make it difficult to evaluate the prospective electricity generating costs for B-IGSOFC relative to B-IGCC. The rough analysis here suggests that B-IGSOFC will not show improved economics relative to B-IGCC at the large scale considered here. © 2009 Society of Chemical Industry and John Wiley & Sons, Ltd [source]


Economic evaluation of surgically trained assistant medical officers in performing major obstetric surgery in Mozambique

BJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 10 2007
ME Kruk
Objective, To compare the training and deployment costs and surgical productivity of surgically trained assistant medical officers (técnicos de cirurgia) and specialist physicians (surgeons and obstetrician/gynaecologists) in Mozambique in order to inform health human resource planning in a developing country with low availability of obstetric care and severe physician shortages. Técnicos de cirurgia have been previously shown to have quality of care outcomes comparable to physicians. Design, Economic evaluation of costs and productivity of surgically trained assistant medical officers and specialist physicians. Setting, Hospitals and health science training institutions in Mozambique. Population, Surgically trained assistants, medical officers, surgeons and obstetrician/gynaecologists in Mozambique. Methods, The costs of training and deploying the two cadres of health workers were derived from a review of budgets, annual expenditure reports, enrolment registers, and accounting statements from training institutions and interviews with directors and administrators. Productivity estimates were based on a hospital survey of physicians and técnicos de cirurgia. Main outcome measures, Cost per major obstetric surgical procedure over 30 years in 2006 US dollars. Results, The 30-year cost per major obstetric surgery was $38.9 for técnicos de cirurgia and $144.1 for surgeons and obstetrician/gynaecologists. Doubling the salaries of técnicos de cirurgia resulted in a smaller but still substantial difference in cost per surgery between the groups ($60.3 versus $144.1 per procedure). One-way sensitivity analysis to test the impact of varying other inputs did not substantially change the magnitude of the cost advantage of técnicos de cirurgia. Conclusion, Training more mid-level health workers in surgery can be part of the response to the health worker shortage, which today threatens the achievement of the health Millennium Development Goals in developing countries. [source]


Randomized clinical trial and follow-up study of cost-effectiveness of laparoscopic versus conventional Nissen fundoplication,

BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 6 2006
W. A. Draaisma
Background: Laparoscopic Nissen fundoplication (LNF) has essentially replaced its conventional open counterpart (CNF). An economic evaluation of LNF compared with CNF based on prospective data with adequate follow-up is lacking. Methods: Data from two consecutive studies (a randomized clinical trial (RCT) of 57 patients undergoing LNF and 46 undergoing CNF that was terminated prematurely, and a follow-up study of 121 consecutive patients with LNF) were combined to determine incremental cost-effectiveness 1 year after surgery. Results: Mean operating time, reoperation rate and hospital costs of LNF were lower in the second series. The mean overall hospital cost per patient was ,9126 for LNF and ,6989 for CNF at 1 year in the initial RCT, and ,7782 in the second LNF series. The success rate of both LNF and CNF at 1 year was 91 per cent in the RCT, and LNF was successful in 90·1 per cent in the second series. A cost reduction of ,998 for LNF would cancel out the cost advantage of CNF. Similarly, if the reoperation rate after LNF decreased from 0·05 to below 0·008 and/or if the mean duration of sick leave after LNF was reduced from 67·2 to less than 61·1 days, the procedure would become less expensive than CNF. Complications, reoperation rate and quality of life after both operations were similar. Conclusion: Including reinterventions, the outcome at 1 year after LNF and CNF was similar. In a well organized setting with appropriate expertise, the cost advantage of CNF may be neutralized. Copyright © 2006 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source]


Seemingly Competitive Food Retail Regulations: Who Do They Really Help?

CANADIAN JOURNAL OF AGRICULTURAL ECONOMICS, Issue 3 2009
Bruno Larue
The food distribution and retail sectors in Quebec are highly concentrated and integrated as large food distributors are also involved in food retailing. As such, they are competing with small grocery and convenience stores they sell inputs to. A review of the industry suggests that there are important economies of size in distribution, but that smaller stores offering convenience face a more inelastic demand. Concerns over the survival of smaller stores in Quebec have motivated two types of regulations. The first type aims at reducing the cost advantage of dominant retailers by restricting the number of employees that they are allowed to use during specific time periods. The second type restricts retail prices. We develop a simple model capturing the main features of the industry to ascertain the impact of these regulations on retail and wholesale prices. Our results suggest that these regulations reduce welfare and may induce both tighter margins and lower surplus for small retailers. Au Québec, les secteurs du commerce de détail et de la distribution des aliments sont fortement concentrés et intégrés puisque les grands distributeurs d'aliments sont aussi engagés dans le commerce de détail. À ce titre, ils font concurrence aux petites épiceries et aux dépanneurs qu'ils approvisionnent. Un examen de l'industrie autorise à penser qu'il existe d'importantes économies de taille dans le secteur de la distribution, mais que les petites épiceries de dépannage sont confrontées à une demande plus inélastique. Les inquiétudes entourant la survie des petites épiceries au Québec ont motivé deux types de règlements. Le premier vise à diminuer l'avantage de coût des détaillants dominants en limitant le nombre d'employés pendant certaines périodes spécifiques. Le deuxième vise à limiter les prix de détail. Nous avons élaboré un modèle simple qui renferme les principales caractéristiques de l'industrie pour évaluer les répercussions de ces règlements sur les prix de détail et de gros. Nos résultats portent à croire que ces règlements diminuent le bien-être et peuvent entraîner un resserrement des marges et une diminution des surplus des petits détaillants. [source]


An Extension of the Structural Change Model to International Economic Relations

METROECONOMICA, Issue 4 2003
Ricardo Azevedo Araujo
ABSTRACT In this paper Pasinetti's model of structural economic dynamics (1981) is extended to consider international economic relations. Conditions for full employment, full expenditure of income and equilibrium of the trade balance are established for an open economy that requires capital goods to produce final commodities. Analytical results concerning the benefits from free trade and international learning are formally studied. In addition, static and dynamic aspects of the ,principle of comparative cost advantage' are analysed considering the determinants of the specialization level. [source]


Securities Laws, Disclosure, and National Capital Markets in the Age of Financial Globalization

JOURNAL OF ACCOUNTING RESEARCH, Issue 2 2009
RENÉ M. STULZ
ABSTRACT As barriers to international investment fall and technology improves, the cost advantages for a firm's securities to trade publicly in the country in which that firm is located and for that country to have a market for publicly traded securities distinct from the capital markets of other countries will progressively disappear. Securities laws remain an important determinant of whether and where securities are issued, how they are valued, who owns them, and where they trade. I show that there is a demand from entrepreneurs for mechanisms that allow them to commit to credible disclosure because disclosure helps reduce agency costs. Under some circumstances, mandatory disclosure through securities laws can help satisfy that demand, but only provided investors or the state can act on the information disclosed and the laws cannot be weakened ex post too much through lobbying by corporate insiders. With financial globalization, national disclosure laws can have wide-ranging effects on a country's welfare, on firms and on investor portfolios, including the extent to which share holdings reveal a home bias. In equilibrium, if firms can choose the securities laws they are subject to when they go public, some firms will choose stronger securities laws than those of the country in which they are located and some firms will do the opposite. [source]


Local Industrial Conditions and Entrepreneurship: How Much of the Spatial Distribution Can We Explain?

JOURNAL OF ECONOMICS & MANAGEMENT STRATEGY, Issue 3 2009
Edward L. Glaeser
Why are some places more entrepreneurial than others? We use Census Bureau data to study local determinants of manufacturing startups across cities and industries. Demographics have limited explanatory power. Overall levels of local customers and suppliers are only modestly important, but new entrants seem particularly drawn to areas with many smaller suppliers, as suggested by Chinitz (1961). Abundant workers in relevant occupations also strongly predict entry. These forces plus city and industry fixed effects explain between 60% and 80% of manufacturing entry. We use spatial distributions of natural cost advantages to address partially endogeneity concerns. [source]


RHEOLOGICAL PROPERTIES OF CRYSTALLIZED HONEY PREPARED BY A NEW TYPE OF NUCLEI

JOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2009
YUE-WEN CHEN
ABSTRACT Good spreadability is a highly desirable quality for crystallized honey used in product applications. In this study, we processed Taiwanese liquid litchi honey into crystallized honey by adding a new nuclei material, namely 0.1% (w/w) glucose powder, instead of the traditional 5,10% (w/w) natural nuclei. Rheological properties of the resulting product were determined during heating and cooling utilizing small amplitude oscillatory shear to assess spreadability. As the product was heated, it exhibited decreased consistency and improved fluidity (evidenced by decreasing storage modulus [G,] and loss modulus [G,] values) and three distinct regions within the G,curve ("softening,""crystalline plateau" and "melting"). As the product was cooled from 55 to 0C, moduli were lower than those obtained during heating, and the product did not exhibit the three G,curve regions across the temperature range. Therefore, we observed incomplete reversible crystallization and rheological properties during temperature migration. Flow properties of crystallized honey in the 0,25C temperature range could be successfully predicted using the Herschel,Bulkley model (R2 > 0.97). However, the product approached Newtonian flow behavior as temperatures neared the upper end of this range. Higher viscosity and lower yield stress were observed at temperatures below 15C. The crystallized honey developed for this study exhibited shear-thinning properties desirable in honey products intended to be spread. PRACTICAL APPLICATIONS Crystallized honey is traditionally prepared by introducing 5,10% natural nuclei into liquid honey. Our lab developed a new method that replaces the natural nuclei with glucose powder, which, at 0.1% (w/w), produces a good quality creamed honey that, in commercial production, offers the potential for significant production cost advantages. As crystallized honey is used in commercial/consumer applications as a spread, its dynamic rheology is of both academic and industrial interest. In this study, we discuss the physical properties of the crystallized honey developed using glucose powder to help better identify the factors and variables involved in honey spreadability and thus facilitate the development of better honey products with more desirable spreadability profiles. This study also provides a rheological properties and spreadability database for crystallized honey that reflects the range of temperature changes that can be expected to occur during normal product storage and use. [source]


RISING WAGES: HAS CHINA LOST ITS GLOBAL LABOR ADVANTAGE?

PACIFIC ECONOMIC REVIEW, Issue 4 2010
Dennis Tao Yang
We document dramatic rising wages in China for the period 1978,2007 based on multiple sources of aggregate statistics. Although real wages increased seven-fold during the period, growth was uneven across ownership types, industries and regions. Over the past decade, the wages of state-owned enterprises have increased rapidly and wage disparities between skill-intensive and labour-intensive industries have widened. Comparisons of international data show that China's manufacturing wage has already converged to that of Asian emerging markets, but China still enjoys enormous labour cost advantages over its neighbouring developed economies. Our analysis suggests that China's wage growth will stabilize to a moderate pace in the near future. [source]


Encumbering harvest rights to protect marine environments: a model of marine conservation easements,

AUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 1 2009
Robert T. Deacon
We adapt the concept of a conservation easement to a marine environment and explore its use to achieve conservation goals. Although marine environments generally are not owned, those who use them for commercial fishing often are regulated. These regulations grant harvesters rights to use marine environments in specified ways, and the possibility of encumbering these rights to achieve conservation goals creates a potential role for marine easements. We examine this potential under alternative fishery management regimes and find, generally, that marine easements tend to be most effective when harvest rights are delineated most fully. Our analysis suggests ways that marine easements can have flexibility and transactions cost advantages over other approaches to achieve marine conservation goals. We also propose ways in which the design of laws allowing marine easements should follow, or depart from, the design of laws authorising conservation easements on land. [source]


Enhanced video streaming network with hybrid P2P technology

BELL LABS TECHNICAL JOURNAL, Issue 3 2008
Yugu Zeng
Hybrid peer-to-peer (P2P) approaches combine the cost advantages of P2P solutions with the quality and capacity characteristics of hosted content server solutions. Thousands of users have home devices providing many streaming and storage resources that promise superior scalability and adaptability over server-based content distribution networks. On the other hand, the involvement of these peers is encumbered by additional latency and resource management overhead. In this paper, we describe how the capacity advantage of hybrid P2P solutions over pure P2P solutions translates into higher achievable bit rates. The modeling and analysis of a heterogeneous architecture presented provides insight into the achievable system latency and design directions for topology resource management. The results indicate the potential of hybrid P2P approaches to serve as a cost-effective streaming platform with bit rates and latency quality close to those of other digital video distribution systems such as digital video broadcast- satellite (DVB-S) or Internet Protocol television (IPTV), but with better deployment flexibility for the future digital media "prosumer" models. © 2008 Alcatel-Lucent. [source]


Continuous Beer Fermentation Using Immobilized Yeast Cell Bioreactor Systems

BIOTECHNOLOGY PROGRESS, Issue 3 2005
Brányik
Traditional beer fermentation and maturation processes use open fermentation and lager tanks. Although these vessels had previously been considered indispensable, during the past decades they were in many breweries replaced by large production units (cylindroconical tanks). These have proved to be successful, both providing operating advantages and ensuring the quality of the final beer. Another promising contemporary technology, namely, continuous beer fermentation using immobilized brewing yeast, by contrast, has found only a limited number of industrial applications. Continuous fermentation systems based on immobilized cell technology, albeit initially successful, were condemned to failure for several reasons. These include engineering problems (excess biomass and problems with CO2 removal, optimization of operating conditions, clogging and channeling of the reactor), unbalanced beer flavor (altered cell physiology, cell aging), and unrealized cost advantages (carrier price, complex and unstable operation). However, recent development in reactor design and understanding of immobilized cell physiology, together with application of novel carrier materials, could provide a new stimulus to both research and application of this promising technology. [source]