bluuebunny/crossref_metadata_2025 huggingface dataset:
Forecasting for solid wastes operations
Authors: Westerman Robert R.
Published: October 2002

This article analyzes the needs for, and capabilities of, formalized forecasting of future workloads to support more effective and efficient solid waste operations management. A case study of computerized forecasting of the average daily solid waste quantity generated, month by month, in Sacramento County, California, is presented. The monthly pattern of peaks and valleys and the month by month trend in solid waste generation are identified. Selected uses of the forecast average, pattern, and trend information in planning for solid waste services and operations are examined. The extent of future workload unpredictability, in Sacramento, in terms of randomness reflected in forecast errors, is identified. The operational consequences of forecast errors are discussed.
Simple methods for uncapacitated facility location/allocation problems
Authors: Sule Dileep R.
Published: October 2002

Facility location/allocation problems are encountered in many different areas of management science. The methods presented in the literature are complex and are not easily understood by practitioners who are not trained in the techniques of optimization. Simple heuristic methods are presented in this article. The methods are developed for three different types of uncapacitated problems: (1) unlimited facility capacity with no fixed cost; (2) unlimited facility capacity with a fixed cost for assignment; (3) multiperiod problems. Examples are included to illustrate the basic methods.
Restarting a forecasting system when demand suddenly changes
Authors: McClain John O.
Published: October 2002

Exponential smoothing is commonly used in automatic forecasting systems. However, when only a small amount of historical data is relevant to future demands, the ad hoc startup methods used in exponential smoothing produce unexpected results. With large data sets, an exponentially smoothed average implicitly weights the data in a declining manner, similar to discounting. This pattern is important in that it minimizes a measure of forecast error. However, restarting with limited data distorts the weighting pattern. A new technique, termed the declining alpha method, is presented and shown to preserve the exponential weight pattern. The key is a formula that changes the smoothing constant each period. Examples are given to illustrate the method and contrast it to other startup techniques.
Simulation study of a closed‐loop job shop
Authors: Glaser Roger B. , Hottenstein Michael P.
Published: October 2002

This study investigates the behavior of a job shop depicted as an integral component of a firm. A market places demands for the firm's products by dynamically evaluating the organization's quoted delivery times and actual delivery performance. The closed‐loop model simulated in this study is described and the salient research results are reported. These experimental outcomes suggest that other conventional open‐loop job shop studies tend to neglect important interactions with factors external to the shop itself.
A cost minimization production planning model for continuous process chemical plant operations
Authors: Eldredge David L. , Holdman Bob
Published: October 2002

The management of large continuous process chemical plants oftentimes must make operating decisions within a rapidly changing economic environment. This paper describes a decision making aid in the form of a production planning model which is immediately responsive to such changes. The model provides cost minimization solutions to “what if” questions of management through the use of linear programming. Implementation upon an interactive computer system provides a user oriented model. A specific type of chemical plant operation involving 13 decision variables illustrates the approach. Five example real‐world situations demonstrate the approach's capability.
Queue control using a historically developed stochastic model
Authors: Ballou Donald P. , Fisk John C.
Published: October 2002

This paper applies a stochastic model to determine the optimal or ideal average planned queue level. The ideal average planned queue level is defined to be the minimum average queue level necessary to ensure that in the long run the probability of work center idle time over a specified planning horizon is no greater than some value α chosen by management. Also discussed is the usefulness of the ideal planned queue level, not only for controlling work‐in‐process inventories, but also for obtaining better work center lead time estimates.
Constrained resource project scheduling subject to material constraints
Authors: Smith‐Daniels Dwight E. , Aquilano Nicholas J.
Published: October 2002

Constrained resource project scheduling techniques schedule project activities subject to finite constraints on the availability of non‐storable resources such as labor and equipment without consideration of constraints resulting from material requirements. Projects are frequently delayed and resources are wasted when project activities are delayed due to material shortages. A heuristic procedure is presented here for scheduling large projects subject to the availability of all necessary resources, including materials, manufactured components, facilities, equipment and labor as well as the acquisition lead times required by these resources. Results are listed for tests involving both benchmark and actual problems.
The retail inventory method: The third major costing system
Authors: Wayne Corcoran A.
Published: October 2002

An organization that has but a single product would be a rarity in the United States today. While single‐product firms and tools such as break‐even analysis may have been in vogue at the turn of the century, today jointness pervades the scene. The bank that issues a mortgage to a customer also may have managed his or her checking account or granted a student loan to his or her daughter. The department store that sold a suit one week earlier may have attracted the customer with its furniture, toys, and cosmetics. The hospital whose obstetrical team delivered the baby may have been chosen because its excellent orthopedics department set the husband's broken leg three years prior. The sporting goods manufacturer may sell its golf clubs because of its reknown for skis and tennis rackets. It makes no difference whether it is products or services or departments; all share equipment, time, and reputation. The list goes on forever; jointness is the rule, not the exception.

Management can pretend that there is only one product and attempt to isolate its effects, as if it were in a vacuum. However, pretending does not eliminate jointness and the purifying assumption is apt to mislead analysis. So how should jointness be treated?

Other than the mathematical programming models of the last forty years, only one model for dealing with jointness has been widely adopted for most of the twentieth century; that model is the retail inventory method. The retail system typically is used by department stores to control inventories that consist of 100,000 or more items.

The retail system recognizes costs and prices, inflation and obsolescence, mistakes and successes. It tracks purchases and sales, deals with discounts and transfers, and controls investment while providing an estimate of ending inventory. Fortunately, the retail system, the favorite of the department store and the boutique, could be used in the factory as well as in a variety of service and nonprofit organizations.

This article briefly reviews the retail method and then uses linear programming (LP) and postoptimality analysis to modernize the traditional conceptions—to attempt to make a good system even better.

Many constraints are studied including overlapping seasons, sales quotas, target inventories, product life cycles, and spatial and monetary limitations, among others. In the process, one comes to appreciate the size of the inventories being controlled, the human and departmental interactions, and the usefulness of the LP‐retail system (“knotty retail” is perhaps an appropriate name) not only to generate cash budget estimates and to manage stock levels, but also to select the most satisfying alterations of managerial policy.

The article concludes by discussing further constraints and other types of organizations that might benefit from adapting the retail system.
Developing maintenance craft labor efficiency through an integrated planning and control system: A prescriptive model
Authors: Finch Byron J. , Gilbert James P.
Published: October 2002

The area of maintenace management has been placed under increasing pressure because of changes in the manufacturing production planning and control systems. In the last few years plant management has been asked to respond to productivity and quality challenges unmatched in business history. The maintenance department plays an important, indeed vital, role in the attainment of improved levels of productivity and quality.

This article examines the relationship between production and maintenance management systems. A conceptual model is developed that integrates the preventive and corrective aspects of maintenance planning with the priority and capacity activities of the production planning system. The model assists management in scheduling maintenance craft labor for additional efficiency and effectiveness.
Procedures for the part family/machine group identification problem in cellular manufacturing
Authors: Wemmerlöv Urban , Hyer Nancy Lea
Published: October 2002

One of the first, and most important, problems faced in the design of a cellular manufacturing system is the identification of part families and machine groups and the simultaneous or subsequent evaluation of the associated cell properties. This cell formation problem is embedded in a larger cell design process. This article first discusses the general cell design process and its objectives and then proposes a framework for structuring the cell formation problem, which encompasses four basic solution approaches. These approaches are based on the fundamental ways part families and machine groups are identified and matched within the cell formation process. The framework is then used to classify descriptive and analytic procedures for the part family/machine group identification problem found in the literature. In all, over 70 such contributions are categorized and briefly reviewed. Promising procedures are identified and areas where additional research is needed are highlighted. It can be concluded that cell formation, despite the reliance on computerized procedures, is a process that is difficult to formalize and that requires a large portion of human insight and decision making.
On apportioning costs to customers in centralized continuous review inventory systems
Authors: Gerchak Yigal , Gupta Diwakar
Published: October 2002

Many manufacturing firms use common production and warehousing resources to jointly supply customers' demands that vary significantly in their variability. For example, it is a common practice in the defense manufacturing industry, while supplying both to the department of defense and the commercial market, to routinely combine safety stocks of the same part meant for different end users, thereby achieving lower overall operating costs. Whereas it might be possible to make a strong case for benefits of centralization (provided this does not result in substantial increases in administrative costs), it is not at all clear that an individual customer will necessarily benefit from centralization under some commonly used methods of allocating inventory costs to customers. For example, if inventory costs are spread evenly over all items stocked (produced), it is possible that a customer will end up paying more (in absolute terms) than what it would have paid on a stand‐alone basis. The purpose of this paper is to first show that it is economical to consolidate. It then investigates some apparently “reasonable” and popular methods of cost allocation to demonstrate their potential for unfairness. It also proposes a method that is fair in the sense that any customer's post‐centralization share of overheads does not exceed its costs without consolidation. The findings of this study are particularly relevant for customers with large steady demands, such as the department of defense, who might inadvertently be subsidizing inventory costs of customers with smaller and more variable demands under an unfair allocation scheme.
An empirical assessment of the perceived relevance and quality of POM‐related journals by academicians
Authors: Barman Samir , Tersine Richard J. , Buckley M.Ronald
Published: October 2002

As in other fields, promotion and tenure decisions of academicians in POM are very closely related to their publication achievements. Such achievements are generally measured by where academicians publish rather than just what they publish. Therefore, the perceived quality or image of POM journals is important to the faculty and researchers in this field. Not surprisingly, several previous studies have attempted to rank order journals belonging to related fields such as accounting, finance, economics and management. Unfortunately, for POM journals, there exist little published data accepted and shared by all in this respect.

The primary objectives of the study are to establish the perceived relevancy and quality ratings of 20 selected journals that are frequently used to disseminate POM‐related research work. The results are based on a questionnaire survey of those Decision Sciences Institute members who listed POM as their primary area of interest (DSI code N).

Regarding relevancy, the Journal of Operations Management is rated as the most relevant journal for POM research. Other journals that received high relevance ratings are: International Journal of Production Research, International Journal of Operations and Production Management, Journal of Manufacturing and Operations Management, Decision Sciences, and Production and Inventory Management Journal. Based on the quality ratings. Management Science, Journal of Operations Management, and Decision Sciences appear to be the “best” journals publishing POM‐related research. IIE Transactions, International Journal of Production Research, Harvard Business Review, Operations Research, Naval Research Logistics, and Journal of Manufacturing and Operations Management form the group of next best journals.

The results provide some evidence of an apparent incongruity between the notions of journal relevancy and journal quality, as perceived by the respondents. Some journals that received high quality ratings were found only moderately relevant to POM research. On the other hand, some journals received poor quality ratings but were rated highly for relevancy. The opinions of the associate and full professors, as well as those with better publication associations with the included journals, were found strikingly similar to those of the entire sample surveyed.

Some discrepancy was evident as to what the respondents and their administrative evaluators think are the top journals. The faculty evaluators tend to consider Management Science and Operations Research as the top two journals in the POM field. Such an observation, along with other pertinent data, suggests that there still exists a tendency to equate POM with OR, and the field, to an extent, is suffering from an identity crisis.
The capacitated dynamic lot‐sizing problem with startup and reservation costs: A forward algorithm solution
Authors: Sandbothe Richard A.
Published: October 2002

Often in production environments, there are several products available to be processed on a machine. The decisions that must be made are: 1) which product should be processed next, and 2) how much time should elapse before a changeover occurs and a different product is chosen for processing. This problem is known as the multiple product cycling problem.

The single product variation of this problem is addressed in this paper. It is assumed that the product to be processed next has already been chosen (decision #1). The second decision concerning production run length must now be determined. In the single product problem, there is a fixed startup cost associated with turning the machine on in a period when the machine was off in the previous period and a fixed reservation cost incurred in each period in which the machine is on. Ending inventory in a period is assessed a holding cost.

The relationship of the single product problem to the multiple period problem is as follows. The startup cost is identical to the changeover cost in the multiple product problem. By processing a particular product, other products must wait. This effect is captured by the reservation cost which is the opportunity cost one would incur by having the machine dedicated to processing a particular product.

A forward dynamic programming algorithm is presented which uses heuristic rules to detect empirical decision horizons. The entire problem is partitioned into smaller Subproblems which are then easily solved. The subproblems are created by the occurrence of startup regeneration points. These are periods where there is no ending inventory and the following period contains a machine startup.

Computational experience is reported which shows that reductions in computational effort (measured in CPU time and the number of nodes in the decision tree evaluated) can be as high as 95 to 99% when using the decision horizon techniques and bounding procedures described in this paper. These results are based on the solution of 28 test problems that were each 20 periods in length. Because a forward algorithm was used, not only were the solutions to the 20‐period problems obtained, but the solutions to the one‐period problems through 19‐period problems were obtained as well. Even though the procedure described in this paper cannot guarantee that it will always find the optimal solution, it did find the optimal solution in every problem tested.

By being able to solve the single product problem presented in this paper quickly, the ability to rapidly generate optimal or near optimal solutions to the multiple product problem (which uses the procedure described in this paper as a subroutine) appears closer to realization.
Overloaded overheads: Activity‐based cost analysis of material handling in cell manufacturing
Authors: Datar Srikant , Kekre Sunder , Mukhopadyay Tridas , Svaan Eric
Published: October 2002

Manufacturing managers today are pressed by aggressive international competitors, high input factor prices, and customers who demand better quality at lower cost. In such an environment, there is a growing need to exploit the time, cost and quality advantages of cell manufacturing (Hyer and Wemmerlöv (1984)). Unfortunately, traditional cost accounting systems may be a major roadblock on the highway to future manufacturing competitiveness. These systems may stifle manufacturing initiatives to improve process design by providing inaccurate cost information. They may also send the wrong signals to managers who must evaluate the cost/benefit impact of process innovation (such as cells and group technology implementation), thereby causing companies to retain outmoded, inefficient manufacturing practices.

We discuss the results of our field study which illustrates the use of activity‐based costing (ABC) to quantify the benefits of cell manufacturing and synchronized process flows. Auto Light Company, a Fortune 500 automobile components manufacturer, had begun to replace its functional layout with synchronous manufacturing cells. Although dramatic progress had been made in operational measures (such as throughput time, work‐in‐process (WIP) inventories, and material flow distance), existing accounting systems failed to trace these savings to the source, namely the change in manufacturing practices. Overheads were being allocated to products on the basis of direct labor or machine hours, which at Auto Light are no different in cells than in traditional manufacturing.

A joint Auto Light management/Carnegie Mellon University team examined the impact of cell manufacturing on major cost categories. The group identified material handling expenses (which exceed $5,000,000 per year, and comprise approximately 10% of total factory costs) as a promising area for analysis using ABC principles. We sought to identify relevant material handling cost drivers: that is, activities that (1) create costs and (2) seem reasonable to use as proxies for assigning costs to products. Interviews, plant records and time‐and‐effort studies pointed to “number of moves” and “distance moved” as key drivers of material handling costs. Annual production volumes, physical dimensions of products and their production routings were used to calculate the number of moves, and the distance
Targeted disruption of LIG‐1 gene results in psoriasiform epidermal hyperplasia1
Authors: Suzuki Yutaka , Miura Hiroyuki , Tanemura Atsushi , Kobayashi Kinji , Kondoh Gen , Sano Shigetoshi , Ozawa Kentaro , Inui Shigeki , Nakata Aya , Takagi Tsutomu , Tohyama Masaya , Yoshikawa Kunihiko , Itami Satoshi
Published: October 2002

The gene encoding a transmembrane glycoprotein LIG‐1, of which the extracellular region was organized with the leucine‐rich repeats and immunoglobulin‐like domains, was disrupted in mice by gene targeting. LIG‐1‐deficient mice developed a skin change on the tail and facial area after birth. The affected skin was histologically reminiscent of the epidermis in human common skin disease ‘psoriasis’. LIG‐1 was expressed in basal cells of the epidermis and outer root sheath cells of hair follicles in mice. Interestingly, the LIG‐1 expression was apparently down‐regulated in the psoriatic lesions, suggesting that LIG‐1 inversely correlates with proliferative ability of epidermal keratinocytes.
Factor Xa induces mitogenesis of coronary artery smooth muscle cell via activation of PAR‐2
Authors: Koo Bon-Hun , Chung Kwang-Hoe , Hwang Ki-Chul , Kim Doo-Sik
Published: October 2002

Factor Xa‐induced stimulation of coronary artery smooth muscle cells (CASMC) was investigated by analyzing [3H]thymidine incorporation, cell proliferation, and ERK‐1/2 activation. Exposure of the cells to factor Xa evoked a time‐dependent activation of ERK‐1/2 with increased [3H]thymidine incorporation and cell proliferation. The factor Xa‐induced ERK‐1/2 activation was not desensitized by preincubation of the cells with thrombin. However, ERK‐1/2 activation was markedly attenuated by prior exposure of the cells to protease‐activated receptor‐2 (PAR‐2) activating peptide, SLIGKV. The mitogenic effect of factor Xa was significantly reduced in the presence of anti‐PAR‐2 monoclonal antibody. Several lines of experimental evidence indicate that factor Xa‐induced mitogenesis of CASMC is a cellular process mediated by PAR‐2 activation.
PP1/PP2A phosphatases inhibitors okadaic acid and calyculin A block ERK5 activation by growth factors and oxidative stress
Authors: Garcia Lourdes , Garcia Fatima , Llorens Franc , Unzeta Mercedes , Itarte Emilio , Gómez Néstor
Published: October 2002

Okadaic acid is an inhibitor of the protein Ser/Thr phosphatases PP1 and PP2A, which blocks the activation of extracellular signal‐regulated protein kinase 5 (ERK5), a member of the MAP kinase family activated by growth factors and several types of stressors. The blocking of ERK5 activation by okadaic acid was observed in HeLa cells exposed to epidermal growth factor and H2O2 as well as in PC12 cells stimulated by nerve growth factor and H2O2. Calyculin A, another PP1 and PP2A inhibitor, behaved similarly although these compounds are not structurally related. This suggests that either PP1 or PP2A or both are necessary for ERK5 activation. Protein kinase C (PKC) acts as a negative regulator of the ERK5 activation pathway, however our data suggest that the effects of PKC and the phosphatase are unrelated.
Experimental study on photodynamic diagnosis of cancer mediated by chemiluminescence probe
Authors: Wang Juan , Xing Da , He Yonghong , Hu Xuejin
Published: October 2002

A novel method of photodynamic diagnosis of cancer mediated by chemiluminescence probe is presented. The mechanism for photodynamic therapy involves singlet oxygen (1O2) generated by energy transfer from photosensitizers. 1O2 can react with 3,7‐dihydro‐6‐{4‐{2‐(N′‐(5‐fluoresceinyl)thioureido)ethoxy}phenyl}‐2‐methylimidazo{1,2‐a}pyrazin‐3‐one sodium salt (FCLA), which is a Cypridina luciferin analog and a specific chemiluminescence probe for detecting 1O2 and superoxide (O2
−). The reaction of FCLA and 1O2 can give emission with peak wavelength at about 532 nm. In the present study, FCLA was chosen as an optical reporter of 1O2 produced from the photosensitization reaction of hematoporphyrin derivative in model solution and in nude mice with transplanted mammary cancer. Photosensitized chemiluminescence from the reaction of FCLA with 1O2 was detected by a highly sensitive Intensified Charge‐Coupled Device detector. The chemiluminescence was markedly inhibited by the addition of 10 mmol/l sodium azide (NaN3) to the model solution and minor effects were observed at the addition of 10 μmol/l superoxide dismutase, 20 mmol/l mannitol and 100 μg/ml catalase, respectively, thus indicating that 1O2 generation from photosensitization reaction mainly results in light emission. Experiments in vivo with tumor‐bearing mice showed a clear chemiluminescence image of tumor. The study suggests that this novel method may be applicable to the diagnosis of superficial tumors.
Cytoskeleton‐related trafficking of the EAAC1 glutamate transporter after activation of the Gq/11‐coupled neurotensin receptor NTS1
Authors: Najimi Mustapha , Maloteaux Jean-Marie , Hermans Emmanuel
Published: October 2002

The possible modulation of the glutamate transporter EAAC1 by a class A G protein‐coupled receptor was studied in transfected C6 glioma cells stably expressing the high‐affinity neurotensin receptor NTS1. Brief exposure (5 min) to neurotensin increased Na+‐dependent D‐[3H]aspartate uptake by about 70%. The effect of neurotensin was found to result from an increase in cell surface expression of EAAC1 and accordingly, cytochalasin D and colchicine were shown to block the effect of neurotensin on aspartate uptake, suggesting that the cytoskeleton participates in this regulation. Neither protein kinase C nor phosphatidylinositol 3‐kinase activities, two intracellular signaling pathways known to modulate EAAC1, was required for EAAC1‐mediated aspartate transport regulation by neurotensin. Together, these results provide evidence for an acute regulation of EAAC1 trafficking after activation of a G protein‐coupled receptor.
Amino‐terminally truncated desmin rescues fusion of des−/− myoblasts but negatively affects cardiomyogenesis and smooth muscle development
Authors: Höllrigl Alexandra , Puz Sonja , Al-Dubai Haifa , Kim Jai Up , Capetanaki Yassemi , Weitzer Georg
Published: October 2002

Desmin fulfils important functions in maintenance of muscle cells and mutations in the desmin gene have been linked to a variety of myopathies. To ascertain the role of desmin's amino‐terminal domain in muscle cells we generated embryonic stem cells constitutively expressing desminΔ1–48 in a null background and investigated muscle cell development in vitro. DesminΔ1–48 lacking the first 48 amino acid residues promotes fusion of myoblasts, rescues myogenesis and down‐regulates vimentin expression in embryoid bodies, but hampers cardiomyogenesis and blocks smooth muscle development. These results demonstrate that desmin's amino‐terminus has different roles in skeletal, cardiac, and smooth muscle cell development and function.
Human l‐3‐phosphoserine phosphatase: sequence, expression and evidence for a phosphoenzyme intermediate
Authors: Collet Jean-François , Gerin Isabelle , Rider Mark H , Veiga-da-Cunha Maria , Van Schaftingen Emile
Published: October 2002

We report the sequence of the cDNA encoding human l‐3‐phosphoserine phosphatase. The encoded polypeptide contains 225 residues and shows 30% sequence identity with the Escherichia coli enzyme. The human protein was expressed in a bacterial expression system and purified. Similar to known l‐3‐phosphoserine phosphatases, it catalyzed the Mg2+‐dependent hydrolysis of l‐phosphoserine and an exchange reaction between l‐serine and l‐phosphoserine. In addition we found that the enzyme was phosphorylated upon incubation with l‐[32P]phosphoserine, which indicates that the reaction mechanism proceeds via the formation of a phosphoryl‐enzyme intermediate. The sensitivity of the phosphoryl‐enzyme to alkali and to hydroxylamine suggests that an aspartyl‐ or a glutamyl‐phosphate was formed. The nucleotide sequence of the cDNA described in this article has been deposited in the EMBL data base under accession number Y10275.
Intensity‐independent fluorometric detection of cellular nitric oxide release
Authors: Andrew Penelope J , Auer Manfred , Lindley Ivan J.D , Kauffmann Harald F , Kungl Andreas J
Published: October 2002

A new fluorescence method is introduced in which nitric oxide (NO)‐derived higher‐order oxygen complexes (NOx) are quantified at physiological pH. Detecting the fluorescence lifetime shift between 2,3‐diaminonaphthalene and the NOx‐derived protonated 2,3‐naphthotriazole allows an intensity independent determination of the NOx concentration. The NO release from LPS and IFNγ‐stimulated murine macrophages and iNOS transfected hamster cells was quantified. The lower detection limit for NO2
− was found to be 800 pmol/ml. Since the influence of static fluorescence quenching due to cellular components can be neglected, the method is applicable for clear cellular supernatants as well as turbid cellular suspensions.
Excess substrate inhibition of soybean lipoxygenase‐1 is mainly oxygen‐dependent
Authors: Berry Hugues , Debat Hélène , Larreta-Garde Véronique
Published: October 2002

Soybean lipoxygenase‐1 kinetics are known to show product and substrate inhibition. With linoleic acid as the substrate and using a simple Michaelis‐Menten formulation, we have shown that K
ss, the substrate inhibition constant was increased by more than five‐fold when initial oxygen concentration was increased from 228 to 1140 μM. Excess substrate inhibition is in fact almost avoided at high initial oxygen concentration. This modification seems correlated with enzyme saturation with oxygen relative to linoleic acid, as reflected by alterations of the substrate conversion rate. Possible implications for the enzyme kinetics are discussed.
Loss of STAT1 expression confers resistance to IFN‐γ‐induced apoptosis in ME180 cells
Authors: Lee Kye Young , Anderson Emily , Madani Kamyar , Rosen Glenn D
Published: October 2002

Interferon gamma (IFN‐γ) induces apoptosis in many tumor cell lines and sensitizes tumor cells to apoptosis by tumor necrosis factor family members. IFN‐γ induces the expression of many early response genes such as interferon regulatory factor‐1 (IRF‐1) by activation of signal transducer and activator of transcription (STAT) factor proteins. We found that ME180 cells became resistant to IFN‐γ‐induced cell death after 4–5 passages in culture. These resistant cells were characterized by a loss of STAT1 expression and a loss of inducible IRF‐1 expression. We describe for the first time the emergence of a STAT1‐deficient ME180 cell line.
In situ ageing of fine beech roots (Fagus sylvatica) assessed by transmission electron microscopy and electron energy loss spectroscopy: description of microsites and evolution of polyphenolic substances
Authors: Watteau Françoise , Villemin Geneviève , Ghanbaja Jaafar , Genet Patricia , Pargney Jean‐Claude
Published: October 2002

Root biomass is quantitatively and qualitatively important in most ecosystems, but its contribution to the pool of organic matter in the soil is not clear. This work was designed to specify root ageing on an ultrastructural scale by transmission electron microscopy combined with microanalysis by electron energy loss spectroscopy. This approach is very suitable for studying the soil/plant interface, and for semi‐quantitative analysis of the evolution of polyphenolic substances during root evolution. Three root segments were studied according to a gradient of root senescence: the apical and basal segments of the mycorrhiza and the mycorrhiza‐carrier root. Each segment contained a certain proportion of senescent cells, some of which were of fungal origin, and this proportion increased as the root aged. In the three segments, the soil/plant interfaces were differentiated, and the micro‐organisms observed in situ were described. Senescent root cells contained many polyphenolic substances and our results showed that these substances were, according to the root segment, differently associated with Ca, N and Si. When all these ultrastructural data are correlated with more global data, they can be usefully applied to root cell physiology, microbiology and pedology. This approach makes it possible to specify the evolution of organic matter in situ in soils whatever its origin.
A suppressive effect of the adenovirus 5 protein E1B 55K on apoptosis induced by IL‐3 deprivation and γ‐irradiation
Authors: Ben Jilani Kamal Eddine , Gaillard Jean‐Philippe , Petit Frédéric , Arnoult Damien , Roumier Anne‐Sophie , Labalette Myriam , Ameisen Jean‐Claude , Estaquier Jérôme
Published: October 2002

The murine IL‐3‐dependent myeloid cell line 32D undergoes a rapid death when deprived of interleukin‐3 (IL‐3), a process that is suppressed or delayed by the constitutive expression of Bcl‐2 or the Bcl‐2‐related Bcl‐xL survival protein. The adenovirus type 5 E1B region encodes an E1B 55K protein, that has been reported to bind and inactivate the p53 protein that plays an important role in the induction of apoptosis. In order to explore the potential effect of the E1B 55K protein on IL‐3 deprival‐induced cell death, we have established 32D cell lines overexpressing the adenovirus E1B 55K protein and compared its ability to modulate the cell death with that of the human Bcl‐2 protein. We observed that E1B 55K, as Bcl‐2, delays the cell death caused by either IL‐3‐deprivation or DNA damage induced by γ‐irradiation. Cell‐cycle analysis after IL‐3 deprivation indicated that surviving Bcl‐2 transfectants accumulate predominantly in the G0/G1 phase of the cell cycle, while E1B 55K transfectants survive in both G0/G1 and the S and G2/M phases of the cell cycle. zVAD‐fmk, a broad caspase inhibitor, prevented chromatin condensation and fragmentation, but not cell death, suggesting that IL‐3 deprivation induces a cell death program in which the caspases are dispensable. In contrast, both E1B 55K and Bcl‐2 allowed cell survival and prevented the typical features of programmed cell death, such as phosphatidyl‐serine exposure, loss of mitochondrial membrane potential, and chromatin condensation and fragmentation. Our findings indicate that the adenovirus 5 E1B 55K protein has the capability to act as a survival factor, and suggest that E1B 55K exerts its effect upstream of the activation of effector caspases, by preventing the loss of mitochondrial membrane potential induced by IL‐3 deprivation.
Global weak solutions for 1+2 dimensional wave maps into homogeneous spaces
Authors: Zhou Yi
Published: October 2002

In this paper, we consider the Cauchy problem of wave maps from 1+2 dimensional Minkowski space into a compact, homogeneous Riemannian manifold. We construct a finite energy global weak solution by a “vanishing viscosity” method.

Dans ce travail nous construisons une solution globale faible avec énergie finie, du problème de Cauchy pour des “application d’ondes” de l’espace de Minkowski à valeurs dans une variété compacte homogène riemannienne.
Propagation of space moments in the Vlasov–Poisson Equation and further results
Authors: Castella F.
Published: October 2002

We show that, if the initial data has moments in the space variable

x

higher than three, then the corresponding solution

ƒ(t, x, v)

of the Vlasov–Poisson System has also moments in

x - vt

higher than three (propagation of high space moments). We also prove the propagation of low moments in the space or in the velocity variable, and state further a priori estimates for solutions of the Vlasov–Poisson System having infinite kinetic energy.

Pour une solution

f = f (t, x, v)

du système de Vlasov–Poisson nous prouvons que, si la donnée initiale

f^0

possède des moments dans la variable d’espace

x

d’ordre plus grand que 3, alors

f

possède également des moments d’ordre plus grand que 3 dans la variable

x - vt

(propagation des moments d’espace d’ordre élevé). Nous prouvons également la propagation des moments d’ordre peu élevé dans les variables d’espace ou de vitesse. Enfin, nous établissons diverses estimations a priori pour des solutions du système de Vlasov–Poisson ayant une énergie cinétique infinie.
Trainee organizations in Europe: a historical overview
Authors: Vermeiren R. , Claes S.
Published: October 2002

An overview of the existing European trainee organizations is not easy to give. The historical tendencies as described in the first part have currently brought about many initiatives. In the second part of this article, a description of the two main European trainee organizations is given.
Elastohydrodynamic rebound of spheres
from coated surfaces
Authors: DAVIS ROBERT H. , RAGER DEAN A. , GOOD BRIAN T.
Published: October 2002

Experiments were performed to measure the rebound velocities of small plastic and
metal spheres dropped from various heights onto a smooth quartz surface coated with
a thin layer of viscous fluid. The spheres stick without rebounding for low impact
velocities, due to viscous dissipation in the thin fluid layer. Above a critical impact
velocity, however, the lubrication forces in the thin layer cause elastic deformation
and rebound of the spheres. The apparent coefficient of restitution increases with the
ratio of the Stokes number to its critical value for rebound, where the Stokes number
is a dimensionless ratio of the inertia of the sphere to viscous forces in the fluid. The
critical Stokes number required for rebound decreases weakly with increasing values
of a dimensionless elasticity parameter which is a ratio of the viscous forces which
cause deformation to the elastic forces which resist deformation. The experimental
results show good agreement with an approximate model based on lubrication theory
for undeformed spheres and scaling relations for elastic deformation.
Numerical simulation of turbulent drag
reduction using micro-bubbles
Authors: XU JIN , MAXEY MARTIN R. , KARNIADAKIS GEORGE EM
Published: October 2002

While turbulent drag reduction through the injection of micro-bubbles into a turbulent
boundary layer is well established in experiments, there is a lack of corresponding
supporting evidence from direct numerical simulations. Here we report on a series
of numerical simulations of small bubbles seeded in a turbulent channel flow at
average volume fractions of up to 8%. These results show that even for relatively
large bubbles, an initial transient drag reduction can occur as bubbles disperse into
the flow. Relatively small spherical bubbles will produce a sustained level of drag
reduction over time.
Short-term effect of human trampling on the upper infralittoral macroalgae of Ustica Island MPA (western Mediterranean, Italy)
Authors: Milazzo M. , Chemello R. , Badalamenti F. , Riggio S.
Published: October 2002

The short-term response of Mediterranean upper infralittoral macroalgal species to experimental human trampling was investigated. Disturbances of six different intensities were applied within the integral reserve of the Ustica Island marine protected area (Italy, Mediterranean Sea). The dominant macroalgal species Cystoseira brachicarpa v. balearica and Dictyota mediterranea were strongly affected by human trampling. Higher levels of disturbance significantly affected both algal percentage cover and canopy at an increasing rate. Three months after trampling, for both variables it was highlighted that the algal recovery from disturbance was incomplete, being significantly different among trampling intensities. The current study revealed that in the short-term it was not possible to identify critical levels of trampling that are sustainable for this shallow community.
Biodiversity associated with Sabellaria alveolata (Polychaeta: Sabellariidae) reefs: effects of human disturbances
Authors: Dubois Stanislas , Retière Christian , Olivier Frédéric
Published: October 2002

Infauna diversity is reported from the Sabellaria alveolata reefs in the bay of Mont Saint-Michel in France, known as the greatest European reef formation. Polychaetes dominate the fauna, but other species also play a role in terms of reef functioning. Species richness of the associated infauna is much higher than that of the surrounding sediments and is concentrated mainly on the reef surface. Species richness clearly varied according to the three stages of reef evolution: the ‘degraded’ reef stage is different from the ‘ball-shaped structure’ and ‘platform’ stages. Multivariate analyses indicate that three species communities can be distinguished, each corresponding to a different stage of reef development. The number of species is very high, but only a few species are restricted to a particular reef stage. Variations of surface topography and spatial heterogeneity can explain unusual associations of species that make infauna associated with S. alveolata reefs very unique.

Moreover, the high densities of S. alveolata (up to 60,000 ind m−2) raise questions regarding the role of the reefs in the ecosystem of the bay. Anthropogenic influences, notably mechanical disturbances due to fishing activity, show a steady increase and may have a serious impact on the assemblage diversity and the ecological stability of the reef, even though recolonization of S.alveolata is possible in degraded reef areas. An important question that must be addressed is whether human activities could influence the role of S. alveolata reefs in the bay of Mont Saint-Michel.
Studies on biomarkers of copper exposure and toxicity in the marine amphipod Gammarus locusta (Crustacea): I. Copper-containing granules within the midgut gland
Authors: Correia A.D. , Costa M.H. , Ryan K.P. , Nott J.A.
Published: October 2002

Sub-lethal exposure of the marine amphipod Gammarus locusta to a range of copper concentrations (Cu) in water and spiked sediments were performed, and the resulting bioaccumulation of Cu into intracellular granules investigated. The presence of Cu-granules was demonstrated histochemically by the rubeanic acid method. The granules were quantified by automated image analyses (expressed as volume fraction, VV). The metal composition of the granules was characterized by X-ray microprobe analysis. The results showed that granules, rich in copper and sulphur, were formed in response to Cu exposure in water and sediment. These granules appeared in the B-cells of the hepatopancreas. VV values increased over the dose-range of Cu compared with control in water (P<0·001) and sediment (P<0·01) exposures. The abundance of the granules also increased with increasing whole-body Cu content, suggesting that at least part of the increasing Cu level was incorporated into the granules, as a strategy for Cu detoxification along with normal storage of Cu during the moult cycle. The presence of sulphur within the granules is thought to represent an organic detoxification mechanism for Cu. The formation of Cu-granules as a cellular response is a useful biomarker of Cu-exposure in ecotoxicological studies with amphipods. The rubeanic acid method is a useful screening tool for this copper.
Has loneliness amongst older people increased? An investigation into variations between cohorts
Authors: VICTOR CHRISTINA R. , SCAMBLER SASHA J. , SHAH SUNIL , COOK DEREK G. , HARRIS TESS , RINK ELIZABETH , DE WILDE STEPHEN
Published: October 2002

Loneliness has been consistently identified as one of the specific ‘social problems’ which accompanies old age and growing older: 90 per cent of the general population of Britain feel that loneliness is a problem associated with old age. There is a widespread presumption that loneliness and isolation have become more prevalent in Britain in the period since the Second World War as a result of the decline in multi-generation households and changes in family structure. This paper examines the accuracy of this stereotype and considers if current cohorts of older people are more likely to report experiencing loneliness than previous generations of elders, through a comparative analysis of historical and contemporary data. Historical data are provided by three ‘classic’ social surveys undertaken in England between 1945 and 1960. Contemporary data are from a postal survey of 245 people aged 65–74 living in South London in 1999. The questions used in all four surveys were comparable, in that respondents self-rated their degree of loneliness on scales ranging from never to always. The overall prevalence of reports of loneliness ranged from five to nine per cent and showed no increase. Loneliness rates for specific age or gender sub-groups were also stable. Reported loneliness amongst those living alone decreased from 32 per cent in 1945 to 14 per cent in 1999, while the percentages decreased for both those reporting that they were never lonely and that they were ‘sometimes’ lonely.
A mathematical model of Staphylococcus aureus control in dairy herds
Authors: ZADOKS R. N. , ALLORE H. G. , HAGENAARS T. J. , BARKEMA H. W. , SCHUKKEN Y. H.
Published: October 2002

An ordinary differential equation model was developed to simulate dynamics of Staphylococcus aureus mastitis. Data to estimate model parameters were obtained from an 18-month observational study in three commercial dairy herds. A deterministic simulation model was constructed to estimate values of the basic (R0) and effective (Rt) reproductive number in each herd, and to examine the effect of management on mastitis control. In all herds R0 was below the threshold value 1, indicating control of contagious transmission. Rt was higher than R0 because recovered individuals were more susceptible to infection than individuals without prior infection history. Disease dynamics in two herds were well described by the model. Treatment of subclinical mastitis and prevention of influx of infected individuals contributed to decrease of S. aureus prevalence. For one herd, the model failed to mimic field observations. Explanations for the discrepancy are given in a discussion of current knowledge and model assumptions.
Permutations with Restricted
Cycle Structure and an
Algorithmic Application
Authors: BEALS ROBERT , LEEDHAM-GREEN CHARLES R. , NIEMEYER ALICE C. , PRAEGER CHERYL E. , SERESS ÁKOS
Published: October 2002

Let q be an integer with q [ges ] 2. We give a new proof of a result of Erdös and Turán
determining the proportion of elements of the finite symmetric group Sn having no cycle of
length a multiple of q. We then extend our methods to the more difficult case of obtaining
the proportion of such elements in the finite alternating group An. In both cases, we derive
an asymptotic formula with error term for the above mentioned proportion, which contains
an unexpected occurrence of the Gamma-function.

We apply these results to estimate the proportion of elements of order 2f in Sn, and
of order 3f in An and Sn, where gcd(2, f) = 1, and gcd(3, f) = 1, respectively, and log f
is polylogarithmic in n. We also give estimates for the probability that the fth power of
such elements is a transposition or a 3-cycle, respectively. An algorithmic application of
these results to computing in An or Sn, given as a black-box group with an order oracle, is
discussed.
English do: on the convergence of languages and linguists
Authors: van der Auwera Johan , Genee Inge
Published: October 2002

This article surveys the debate on the origin of periphrastic do, with particular attention to the hypothesis that Celtic languages might have exerted some influence. With respect to the facts, it is argued that there are various types of Celtic hypotheses and that one type is sensible, though unlikely to be proven and even less likely to be proven to be the only relevant factor. With respect to the debate itself, it is shown that a Celtic origin hypothesis is accepted more widely among non-British scholars, and we speculate why that might be the case.