bluuebunny/crossref_metadata_2025 huggingface dataset:
The future of knowledge management: an international delphi study
Authors: Scholl Wolfgang , König Christine , Meyer Bertolt , Heisig Peter
Published: May 2004

The field of knowledge management (KM) is highly estimated in research and practice but at the same time relatively diffuse and scattered into diverging concepts, perspectives and disciplines. On that background, it was the aim of this delphi study to give more structure to the field of KM and to get an outlook on worthwhile developments for the next ten years. International experts of KM from natural/technical and social/business sciences as well as practicians of KM with a similar background were asked some basic questions onto the future of KM in two rounds. According to the experts, the future of knowledge management lies in a better integration into the common business processes, a concentration on the human‐organization‐interface and a better match of IT‐aspects to human factors whereas IT‐aspects rank low on this agenda. There are no broadly agreed theoretical approaches though something can be gained from the related organizational learning field; in general much more interdisciplinary and empirical research is needed. There are also almost no broadly agreed practical approaches besides communities of practice.
How Robust is the Kearney/Foreign Policy Globalisation Index?
Authors: Lockwood Ben
Published: May 2004

We argue that the Kearney/Foreign Policy (KFP) index of globalisation is constructed by making some problematic assumptions about the measurement, normalisation and weighting of the variables included in the index. We propose alternative measurement, normalisation and weighting rules, and using these rules, recalculate the ranking of the fifty countries, using the original KFP data. Specifically, we use, in various combinations: (i) variables ‘adjusted’ for geographical characteristics of countries; (ii) statistically optimal weights obtained by principal components analysis; (iii) a normalisation rule that treats different years of observations separately. We find that the country rankings change significantly when adjusted variables are used, indicating that the original KFP index is partially measuring geographical differences between countries.
The Dilemma of Enlargement for the European Union's Regional Policy
Authors: Van Der Beek Gregor , Neal Larry
Published: May 2004

The integration of the former communist countries of central and eastern Europe into the European Union creates a dilemma for the EU's regional policy. The EU's expenditure on regional policy (its ‘active’ regional policy) has been guided by political reactions to deepening or enlarging the EU, not by a rational strategy for regional policy. In contrast, the strong EU instrument of state aid control, developed for competition policy (its ‘reactive’ regional policy) has been relatively successful in avoiding a national race of regional subsidies among the member states. We show that a shift from active regional policy to reactive, competition‐oriented, regional policies is the preferred way for the established member states to handle the challenge of enlargement. At the same time, however, this shift is politically difficult for the accession countries to accept, despite the fact that this shift might prove better for them economically. This regional policy dilemma is one of the major obstacles for the full integration of the accession countries into the EU.
Ideas, Interests and Oil Prices: The Political Economy of Trade Reform During Soeharto's Indonesia
Authors: Basri M. Chatib , Hill Hal
Published: May 2004

Indonesia since the late 1960s constitutes an excellent case study in the political economy of trade protection. There have been major changes in the overall policy regime, from liberalism to significant intervention, and back towards liberalism. There have been large, though declining, inter‐industry variations in effective protection. There has been a lively domestic debate, much of it dominated by non‐economists. Many actors at home and abroad have a stake in that debate. And, since the 1980s at least, trade policy interventions have been reasonably well documented and quantified. In this paper, we show how quantitative analysis may be employed to shed light on changes in the trade policy regime over time. We also examine the principal actors with an interest in, and influence over, trade policy, delineating where possible how their influence translated into the policy arena. Finally, we speculate on whether the framework developed in this paper is applicable to the very different circumstances prevailing in the post‐Soeharto era.
Reforming the Governance of the International Monetary Fund
Authors: Kelkar Vijay , Yadav Vikash , Chaudhry Praveen
Published: May 2004

Democratising the governance of the IMF will significantly improve the institution's capacity to manage crises. The implementation of a democratic framework requires a reform of the Fund's ‘quota regime,’ which mediates the distribution of voting power. An optimal reform of the quota regime that reflects the increased weight of emerging economies requires matching the number of policy objectives with the number of policy instruments. Presently, there is a classic ‘assignment problem’ whereby one policy instrument (i.e., the quota regime) is aimed at achieving three objectives (i.e., member contribution obligations, access rights, and voting rights). Three different instruments need to be adopted. Member contributions should be based on member's capacity to pay; access to resources should be based on need; and voting rights should balance the rights of creditors with the principle of sovereign equality. These reforms will enhance the Fund's legitimacy and accountability as a forum for global economic policy‐making.
Antipruritic effects of two different 5‐HT3 receptor antagonists and an antihistamine in haemodialysis patients
Authors: Weisshaar Elke , Dunker Nadine , Röhl Friedrich‐Wilhelm , Gollnick Harald
Published: May 2004

Abstract:  Pruritus is the most distressing symptom in haemodialysis (HD) patients. Its aetiology has not yet been delineated, and thus there are no good therapeutical options. Case reports and series attribute antipruritic potency to the serotonin receptor antagonists of the 5‐HT3 type in renal pruritus. It was the aim of this study to investigate the antipruritic effect of two different 5‐HT3 receptor antagonists and an antihistamine in 11 patients undergoing HD. Pruritus was induced by iontophoresis with serotonin and histamine and recorded before and after HD. These data were compared to those obtained after oral pretreatment with the 5‐HT3 receptor antagonists tropisetron 5 mg and ondansetron 8 mg and the antihistamine cetirizine 10 mg. Ten healthy volunteers served as a control group. Vasocutaneous parameters (wheal and flare), skin temperature and alloknesis were also determined. Itching in HD patients and controls was not significantly diminished by oral pretreatment with the serotonin receptor antagonists. In controls, but not in HD patients, cetirizine significantly reduced itching, skin temperature and vasocutaneous parameters. Our data additionally demonstrate that there are no significant differences in vasocutaneous parameters, itching and alloknesis in HD patients before and after dialysis. We conclude that 5‐HT3 receptor blockers such as tropisetron and ondansetron and the antihistamine cetirizine do not sufficiently reduce serotonin‐ and histamine‐induced itching in haemodialyis patients.
Officers or engineers? The integration and status of engineers in the Royal Navy, 1847–60*
Authors: Walton Oliver C.
Published: May 2004

This article, using engineers' diaries and Admiralty papers, discusses the status and integration of engineers into the Navy from 1847–60. With the birth of the steam fleet, they were recruited in large numbers as officers, to operate and maintain the engines. Their position as officers and engineers, nascent executive and technical, proved controversial. Literature on the introduction of steam has neglected the social dimension and coverage of naval engineers has not emphasized their challenge to the established ethos of the officer corps. This article seeks to remedy this by examining engineers' work and relationships with both officers and the Admiralty.
Cytokinin stimulates polyribosome loading of nuclear‐encoded mRNAs for the plastid ATP synthase in etioplasts of Lupinus luteus: the complex accumulates in the inner‐envelope membrane with the CF1 moiety located towards the stromal space
Authors: Sherameti Irena , Shahollari Bationa , Landsberger Martin , Westermann Martin , Cherepneva Galina , Kusnetsov Victor , Oelmüller Ralf
Published: May 2004

Three of the nine subunits of the plastid ATP synthase, including the subunit of the CF1 moiety (gene AtpC), are encoded in the nucleus. Application of cytokinin to etiolated lupine seedlings induces polyribosome association of their mRNAs. This appears to be specific as no such regulation was observed for messages for three ribosomal proteins. Cytokinin‐mediated polyribosome loading was also observed for the spinach AtpC message in etiolated transgenic tobacco seedlings. Analysis of various spinach AtpC mRNA derivatives uncovered that the 5′ untranslated region (5′ UTR) of this message is sufficient to direct polyribosome loading, and that sequences at the 3′ end of the AtpC 5′ UTR, including an UC‐rich motif, are crucial for this regulation. The increase in polyribosome loading of the AtpC message correlated with an increased synthesis of the polypeptide. The subunit, together with the ATP synthase complex, accumulates in the inner‐envelope membrane with the CF1 moiety located towards the stromal space of the etioplast. These results suggest that cytokinin promotes accumulation of the ATP synthase in the inner‐envelope membrane of lupine etioplasts by stimulating the translation efficiency of their nuclear‐encoded messages.
Sorting signals in the cytosolic tail of membrane proteins involved in the interaction with plant ARF1 and coatomer
Authors: Contreras Inmaculada , Ortiz‐Zapater Elena , Aniento Fernando
Published: May 2004

In mammals and yeast, a cytosolic dilysine motif is critical for endoplasmic reticulum (ER) localization of type I membrane proteins. Retrograde transport of type I membrane proteins containing dilysine motifs at their cytoplasmic carboxy (C)‐terminal tail involves the interaction of these motifs with the COPI coat. The C‐terminal dilysine motif has also been shown to confer ER localization to type I membrane proteins in plant cells. Using in vitro binding assays, we have analyzed sorting motifs in the cytosolic tail of membrane proteins, which may be involved in the interaction with components of the COPI coat in plant cells. We show that a dilysine motif in the −3,−4 position (relative to the cytosolic C‐terminus) recruits in a very specific manner all the subunits of the plant coatomer complex. Lysines cannot be replaced by arginines or histidines to bind plant coatomer. A diphenylalanine motif in the −7,−8 position, which by itself has a low ability to bind plant coatomer, shows a clear cooperativity with the dilysine motif. Both dilysine and diphenylalanine motifs are present in the cytosolic tail of several proteins of the p24 family of putative cargo receptors, which has several members in plant cells. The cytosolic tail of a plant p24 protein is shown to recruit not only coatomer but also ADP ribosylation factor 1 (ARF1), a process which depends on both dilysine and diphenylalanine motifs. ARF1 binding increases twofold upon treatment with brefeldin A (BFA) and is completely abolished upon treatment with GTPγS, suggesting that ARF1 can only interact with the cytosolic tail of p24 proteins in its GDP‐bound form.
Herbivore‐induced plant vaccination. Part I. The orchestration of plant defenses in nature and their fitness consequences in the wild tobacco Nicotiana attenuata
Authors: Kessler André , T. Baldwin Ian
Published: May 2004

A plant's responses to attack from particular pathogens and herbivores may result in resistance to subsequent attack from the same species, but may also affect different species. Such a cross‐resistance, called immunization or vaccination, can benefit the plant, if the fitness consequences of attack from the initial attacker are less than those from subsequent attackers. Here, we report an example of naturally occurring vaccination of the native tobacco plant, Nicotiana attenuata, against Manduca hornworms by prior attack from the mirid bug, Tupiocoris notatus (Dicyphus minimus), which results from the elicitation of two categories of induced plant responses. First, attack from both herbivore species causes the plants in nature to release predator‐attracting volatile organic compounds (VOCs), and the attracted generalist predator, Geocoris pallens, preferentially attacks the less mobile hornworm larvae. Second, attack from both mirids and hornworms increases the accumulation of secondary metabolites and proteinase inhibitors (PIs) in the leaf tissue, which is correlated with the slow growth of Manduca larvae. Mirid damage does not significantly reduce the fitness of the plant in nature, whereas attack from the hornworm reduces lifetime seed production. Consequently, plants that are attacked by mirids realize a significant fitness advantage in environments with both herbivores. The combination of growth‐slowing direct defenses and predator‐attracting indirect defenses results in greater hornworm mortality on mirid‐attacked plants and provides the mechanism of the vaccination phenomenon.
Local recurrence of a unilateral cystic nephroma
Authors: BASTIAN PATRICK J. , KUHLMANN RICHARD , VOGEL JÜRGEN , BASTIAN HANS‐PETER
Published: May 2004

Cystic nephroma is an uncommon, benign renal lesion. We report the first case of local recurrence of a unilateral cystic nephroma in an adult. Only three cases of recurrence in bilateral cystic nephroma have been described in the literature before. Other renal lesions may not be differentiated preoperatively from cystic nephroma and thus require surgical exploration. Long‐term follow‐up is recommended to rule out local recurrence.
Prevalence of and risk factors for nocturia: Analysis of a health screening program
Authors: YOSHIMURA KOJI , TERADA NAOKI , MATSUI YOSHIYUKI , TERAI AKITO , KINUKAWA NAOKO , ARAI YOICHI
Published: May 2004

Background: We examined the prevalence of and risk factors for nocturia in Kurashiki city and the surrounding area, a rural area in Japan.

Materials and Methods
:
We collected data on 6517 individuals (4568 men and 1949 women) who participated in a multiphasic health screening. We analyzed the relationships between nocturia assessed by a questionnaire (voiding twice or more during night) and other variables including age, hypertension, cardiovascular disease, cerebrovascular disease, chronic obstructive pulmonary disease, diabetes mellitus (DM), chronic renal failure, benign prostatic hyperplasia (BPH), smoking habit and alcohol intake.

Results: Overall, 1856 individuals (28.5%) answered that they arose to urinate at least twice during the night. This rate increased with age from 16.5% in individuals younger than 50 to 60.0% in those older than 69. Logistic regression analysis revealed that cohorts of subjects 50–59, 60–69, and 70 years old or over had, respectively, 1.75, 3.35, and 6.21 times the prevalence of nocturia of the 49 years or younger cohort. Hypertension (odds ratio [OR] 1.64) and DM (OR 1.70) were other independent positive risk factors for nocturia. On the other hand, current smokers who smoked 20 or more cigarettes per day were less likely to have nocturia than non‐smokers (OR 0.72). In male individuals, BPH was another independent positive risk factor (OR 1.35). Gender was not associated with nocturia.

Conclusions
:
Although population bias is an important limitation to this study, nocturia is associated with various factors suggesting that multiple approaches are needed to the treatment of patients with nocturia.
Adrenal myelolipoma associated with adenoma
Authors: MANASSERO FRANCESCA , POMARA GIORGIO , RAPPA FRANCESCA , CUTTANO MARIA GIUSEPPA , CRISCI ALFONSO , SELLI CESARE
Published: May 2004

The association of an adrenal myelolipoma with a non‐functioning adenoma is very rare. Herein, we report on such a case in an asymptomatic 64‐year‐old woman. To the best of our knowledge, there is only one other case of non‐functioning adrenocortical adenoma associated with myelolipoma in the same gland. Furthermore, only two other adenomas (mineral corticoids and corticosteroid producing tumors) associated with myelolipomas have been reported, and both myelolipomas were less than 1 cm in size. In conclusion, the 8.5 cm myelolipoma in our case is the largest compared with the three previously reported ones.
A risk index for prostate cancer
Authors: MATCHARIYAKUL CHAIYASIT , KOCHAKARN WACHIRA , CHAIMUANGRAJ SUCHART , LEENANUPUNTH CHAREON , LERTSITHICHAI PANUWAT
Published: May 2004

Background: The aim of the present study was to create a simple numerical index predicting the presence of prostate cancer in a group of high risk patients, for the purpose of selecting those most likely to need prostate biopsy.

Methods: 100 consecutive patients at high risk of having prostate cancer seen at Ramathibodi Hospital, Thailand between November 2000 and February 2002 were prospectively studied. All patients underwent transrectal prostate biopsies. The following predictor variables were obtained: age, digital rectal examination (DRE) findings, prostate specific antigen level, transrectal ultrasonography (TRUS) findings, and prostate volume determined by TRUS. The outcome was the presence of prostate cancer on histological examination of the biopsy specimens. A risk index for prostate cancer based on the linear predictor of a multiple logistic regression model was created.

Results: Almost all predictor variables were significantly related to the presence of prostate cancer. The final multiple logistic regression model with four categorized predictors (excluding DRE) was shown to have good discrimination, calibration, and cross‐validity. For a cutoff risk index of 10, corresponding to a 10% probability of having prostate cancer, the sensitivity for detecting prostate cancer was 96.2%, with a specificity of 73.0%. Based on this cutoff, 55% of patients in this series might not require prostate biopsy.

Conclusion: A risk index for prostate cancer was developed. If this index can be externally validated, the potential savings from avoiding unnecessary prostate biopsies, on the basis of selection using the index, could be significant.
The neuronal and endothelium‐dependent relaxing responses of human corpus cavernosum under physiological oxygen tension last longer than previously expected
Authors: KIMURA KAZUNORI , KAWANISHI YASUO , KAGAWA SUSUMU
Published: May 2004

Background: Intracavernosal oxygen tension varies greatly in the process of erection. Blood extracted from the human penis demonstrates an increase from approximately 30 mmHg Po2 in the flaccid state to 100 mmHg in the erect state of the penis. In the present study, using these levels as a guide, we investigate how the NO‐dependent relaxation of human corpus cavernosum changed under physiological oxygen tensions ranging from approximately 30 to 100 mmHg.

Methods: Human penile tissue specimens were obtained at penile surgery with informed consent from the patients. The preparations were mounted in Krebs solution in an organ bath and the isometric tension was recorded. Krebs solutions of various oxygen tensions were prepared by bubbling 5% CO2 in N2 and O2. The NO‐dependent relaxation caused by electrical field stimulation (EFS) and acetylcholine (ACh) was studied, and the amplitude and duration of relaxation evaluated.

Results: The amplitude of relaxation induced by EFS was significantly decreased under physiological oxygen tension conditions (P < 0.01). The duration of the relaxant response induced by EFS and ACh was significantly prolonged in physiological oxygen tension conditions than in high oxygen tension (P < 0.01). However, there was no correlation between the duration of relaxation induced by EFS and each physiological oxygen tension level. The duration of relaxation induced by ACh was most prolonged at 60–69 mmHg oxygen tension.

Conclusion: Physiologically, the effect of NO may last longer than was previously thought. In addition, it would seem that there is an optimal physiological oxygen tension for maximum ACh‐induced relaxation.
The Nature of Legal Philosophy
Authors: Alexy Robert
Published: May 2004

Abstract.  Philosophy is general and systematic reflection about what there is, what ought to be done or is good, and how knowledge about both is possible. Legal philosophy raises these questions with respect to the law. In so doing, legal philosophy is engaged in reasoning about the nature of law. The arguments addressed to the question of the nature of law revolve around three problems. The first problem addresses the question: In what kinds of entities does the law consist, and how are these entities connected such that they form the overarching entity we call “law”? The answer is that law consists of norms as meaning contents which form a normative system. The second problem addresses the question of how norms as meaning contents are connected with the real world. This connection can be grasped by means of the concepts of authoritative issuance and social efficacy. The latter includes the concept of coercion or force. The third problem addresses the correctness or legitimacy of law, and, by this, the relationship between law and morality. To ask about the nature of law is to ask about necessary relations between the concepts of normative meaning, authoritative issuance as well as social efficacy, and correctness of content.
Deduction and Justification in the Law. The Role of Legal Terms and Concepts
Authors: Lindahl Lars
Published: May 2004

Abstract.  Legal terms, such as “ownership,”“contract,”“validity,”“negligence,” are used as middle terms in legal deduction. The paper distinguishes two problems regarding this use. One is the logical function of terms for deduction within a normative system. Specific problems dealt with in this connection are meaning, definition, and economy of expression. The other problem connected with middle terms is the “moulding” and possible manipulation of the meaning of legal terms, for arriving at desired conclusions in a given scheme of inference. It is indicated how the moulding of contested legal concepts, if not restricted, will obscure the ratio of legal rules. This problem is relevant, inter alia, to arguments ex analogia in the law.
Common and rare side‐effects of low‐dose thalidomide in multiple myeloma: focus on the dose‐minimizing peripheral neuropathy
Authors: Offidani Massimo , Corvatta Laura , Marconi Monica , Malerba Lara , Mele Anna , Olivieri Attilio , Brunori Marino , Catarini Massimo , Candela Marco , Capelli Debora , Montanari Mauro , Rupoli Serena , Leoni Pietro
Published: May 2004

Objectives: Thalidomide has demonstrated a remarkable efficacy in the treatment of multiple myeloma but its use may cause several toxicities. We have investigated the common and rare side‐effects, especially analysing peripheral neuropathy, in order to optimise the thalidomide dose for minimizing this harmful side‐effect.

Methods: Fifty‐nine patients were treated with thalidomide alone or combined with oral melphalan. The median age was 69 yr. The initial dose of thalidomide was 100 mg/day increasing weekly by 100 mg increments until a maximum dose of 400 mg was attained. Melphalan was administered at a dose of 0.20 mg/kg/d for 4 d every 28 d.

Results and conclusions: Nearly one‐fourth of patients discontinued thalidomide because of toxicity. Constipation (71%), somnolence (36%) and fatigue (20%) were the most common side‐effects and they were not dose dependent. Peripheral neuropathy occurred in 39% of patients and a thalidomide median daily dose of more than 150 mg was significantly associated with higher frequency and actuarial risk of peripheral neuropathy without improving the response rate. Deep venous thrombosis was observed in 7% of patients and other side‐effects were rare. In patients with advanced multiple myeloma we found that a thalidomide daily dose of 150 mg minimizes peripheral neuropathy without jeopardizing response and survival.
Reduced intensity allogeneic stem cell transplantation for systemic primary amyloidosis refractory to high‐dose melphalan
Authors: Kawai Yasukazu , Kinoshita Keiichi , Arai Hajime , Kuwata Atsushi , Fukuoka Yoshitomo , Yamaoka Masanobu , Imamura Shin , Tsutani Hiroshi , Ueda Takanori
Published: May 2004

Complete elimination of the plasma cell dyscrasia is a rational therapeutic goal, as intercepting supply of precursor protein is a necessary condition for a major regression of amyloid deposits. High‐dose melphalan with autologous stem cell transplantation has shown the ability to induce complete hematological response (HR) along with recovery of organ dysfunction. However, the rate of HR with this treatment rarely exceeds 40%. We describe here the first known case of successful reduced intensity allogeneic stem cell transplantation (RIST) for a patient with primary amyloidosis complicated with nephrotic syndrome but without cardiac disease, who had obtained only partial HR by high‐dose melphalan with autologous stem cell transplantation. RIST may be feasible and be capable of achieving complete HR along with recovery from nephrotic syndrome with acceptable toxicity.
Utilization of triacylglycerol‐rich lipoproteins by the working rat heart: routes of uptake and metabolic fates
Authors: Niu You‐Guo , Hauton David , Evans Rhys D.
Published: May 2004

Very‐low‐density lipoprotein (VLDL) and chylomicrons (CMs) transport triacylglycerol (TAG) to peripheral tissues. Lipoprotein‐TAG may gain access to target cells by lipoprotein lipase (LPL) hydrolysis or via receptor‐mediated uptake; the principal routes of entry of VLDL and CM into heart are unknown, and different routes of entry may result in different metabolic fates. To examine this, isolated working rat hearts were perfused with rat VLDL and CMs, dual‐labelled with [3H]TAG and [14C]cholesterol. Uptake and utilization of CM‐TAG were significantly greater than VLDL‐TAG, but both were decreased significantly (more than halved) by tetrahydrolipstatin (THL, an inhibitor of lipoprotein lipase). By contrast, uptake of VLDL‐cholesterol was much higher than CM‐cholesterol (P < 0.01), and suramin (a lipoprotein receptor antagonist) decreased cholesterol uptake of both forms. CM‐TAG oxidation rate was more than 4‐fold higher than VLDL‐TAG oxidation. However, suramin decreased TAG oxidation from both VLDL and CM without affecting TAG uptake or total utilization, suggesting that the TAG gaining access through receptor‐mediated pathways is preferentially ‘channelled’ towards oxidation. Most (79%) CM‐TAG was oxidized whilst the proportion of VLDL‐TAG oxidized was only about half (49%). In the presence of suramin, there was a significant increase in esterification (incorporation of assimilated [3H]TAG into myocardial tissue [3H]lipids, mainly TAG) of assimilated TAG from both VLDL and CMs, again suggesting that receptor‐mediated TAG uptake is directed towards oxidation rather than esterification. The importance of this relatively small pool of TAG is indicated by the fact that cardiac mechanical function declined markedly when lipoprotein receptors were inhibited. These results suggest that CMs, most fatty acids of which gain access into cardiomyocytes through LPL‐mediated hydrolysis, are the major supplier of TAG for hearts to oxidize; however, the metabolic fate of VLDL was split evenly between oxidation and deposition as myocardial tissue lipid. Most importantly, VLDL may play a regulatory role in heart lipid metabolism through a lipoprotein receptor‐mediated mechanism.
Direct Method for Determining Natural Frequencies of Marine Risers in Deep Water
Authors: Graves Jason R. , Dareing Don W.
Published: May 2004

This paper presents a direct method for determining natural frequencies of lateral modes of vibration for marine risers in deep water. This method applies to marine risers that are vertical, relatively straight, and attached at both ends. The method is particularly useful for determining natural frequencies of higher modes that are sometimes difficult to obtain analytically or numerically. Comparisons of numerical results with published data show that even though the method of solution is approximate, the calculation procedure gives useful engineering results. The algorithm is based on classical vibration theory and can easily be programmed on portable computers for direct use on offshore oil rigs.
Experimental Study of Bubble Dynamics on a Micro Heater Induced by Pulse Heating
Authors: Hong Y. , Ashgriz N. , Andrews J.
Published: May 2004

An experimental investigation of the rapid formation and collapse of bubbles formed on a micro heater (25×80 μm2) is presented. Short electric pulses in the range of 1 μs to 4 μs are applied to the resistive heater, which is immersed in deionized water and generates a heat flux of more than 750 MW/m2. A stroboscopic technique with a time resolution of 30 ns and spatial resolution of 2 μm was used to capture the dynamics of the bubble growth and collapse. From the nucleation theory, the nucleation temperatures are close to the kinetic limit of superheat and weakly depends on the heating rate. The velocity, acceleration, and the pressure profiles after the vapor sheet formation are presented.
A Leidenfrost Point Model for Impinging Droplets and Sprays
Authors: Bernardin John D. , Mudawar Issam
Published: May 2004

This study presents, for impinging droplets and sprays, a model of the Leidenfrost point (LFP); the minimum liquid/solid interface temperature required to support film boiling on a smooth surface. The present model is an extension of a previously developed sessile drop model, based on bubble nucleation, growth, and merging criteria, as well as surface cavity size characterization [3]. The basic concept of the model is that for liquid/solid interface temperatures at and above the LFP, a sufficient number of cavities are activated and the bubble growth rates are sufficiently fast that a continuous vapor layer is established nearly instantaneously between the liquid and the solid. For impinging droplets, the influence of the rise in interfacial pressure created by the impact of the droplet with the surface, must be accounted for in determining fluid properties at the liquid-solid interface. The effect of droplet impact velocity on the LFP predicted by the model is verified for single impinging droplets, streams of droplets, as well as sprays. While the model was developed for smooth surfaces on which the roughness asperities are of the same magnitude as the cavity radii (0.1–1.0 μm), it is capable of predicting the boundary or limiting Leidenfrost temperature for rougher surfaces with good accuracy.
Comparative Study of Four Shadow Band Diffuse Irradiance Correction Algorithms for Almerı´a, Spain
Authors: Lo´pez G. , Muneer T. , Claywell R.
Published: May 2004

Diffuse irradiance is a fundamental component in solar resource considerations. Diffuse irradiance can be accurately determined by calculation from global and beam normal (direct) measurements. However, beam solar measurements can be expensive and therefore shadow bands are often used along with pyranometers to mask the solar disk. The errors that result from the use shadow bands are well known and have been studied by numerous authors. The thrust of this article is to examine four recognized correction techniques for correcting shadow band based diffuse irradiance and statistically evaluate their individual performances using data collected in Almerı´a, Spain. Almerı´a is located in southern Spain and has a healthy solar irradiation budget.
Measurement of Temperatures on In-Flight Water Droplets by Laser Induced Fluorescence Thermometry
Authors: Salazar V. M. , Gonza´lez J. E. , Rivera L. A.
Published: May 2004

This work presents the use of laser induced fluorescence for instantaneous temperature measurements of 200 μm water droplets in a monodisperse stream while traveling downward in a standard stagnant atmosphere. The droplets are doped with small concentrations of a natural fluorescence dye (Pyrene), and with a surfactant substance, cetyldimetylbenzylammoniumchloride (CDBAC) to improve the fluorescence emission and the rate of its two band emission (excimer to monomer) is used to determine the temperature. The temperature distribution along the stream of droplets was determined for three different initial temperatures: 30°C, 40°C, and 50°C at the exit of the nozzle and it is compared very favorably with numerical results.
Optimal Airflow Control of Laboratory Air Handling Unit (LAHU) Systems
Authors: Cui Yujie , Liu Mingsheng , Conger Kirk
Published: May 2004

The Laboratory Air Handling Unit (LAHU) system conditions both the office section and the laboratory section. It improves indoor air quality by maximizing outside air intake to the office section and minimizes thermal energy consumption by re-circulating the office section air to the laboratory section. This paper presents a theoretical linear optimization method and results of optimal outside air control in LAHUs. The optimal outside airflows are expressed as functions of the weather conditions (outside air temperature and enthalpy), office and laboratory airflow rates, office and laboratory supply air temperatures, and four dimensionless parameters that describe the building system and energy characteristics. The optimization method used in this paper can be used to identify the optimal control schedules in other HVAC systems.
Pattern Recognition for Automatic Machinery Fault Diagnosis
Authors: Sun Qiao , Chen Ping , Zhang Dajun , Xi Fengfeng
Published: May 2004

We present a generic methodology for machinery fault diagnosis through pattern recognition techniques. The proposed method has the advantage of dealing with complicated signatures, such as those present in the vibration signals of rolling element bearings with and without defects. The signature varies with the location and severity of bearing defects, load and speed of the shaft, and different bearing housing structures. More specifically, the proposed technique contains effective feature extraction, good learning ability, reliable feature fusion, and a simple classification algorithm. Examples with experimental testing data were used to illustrate the idea and effectiveness of the proposed method.
Nonlinear Viscoelastic Material Property Estimation of Lower Extremity Residual Limb Tissues
Authors: To¨nu¨k Ergin , Silver-Thorn M. Barbara
Published: May 2004

Axisymmetric nonlinear finite-element analysis was used to simulate force-relaxation and creep data obtained during in vivo indentation of the residual limb soft tissues of six individuals with trans-tibial amputation [1]. The finite-element models facilitated estimation of an appropriate set of nonlinear viscoelastic material coefficients of extended James-Green-Simpson material formulation for bulk soft tissue at discrete, clinically relevant test locations. The results indicate that over 90% of the experimental data can be simulated using the two-term viscoelastic Prony series extension of James-Green-Simpson material formulation. This phenomenological material formulation could not, however, predict the creep response from relaxation experiments, nor the relaxation response from creep experiments [2–5]. The estimated material coefficients varied with test location and subject indicating that these coefficients cannot be readily extrapolated to other sites or individuals.
Measurements of Mouse Pulmonary Artery Biomechanics
Authors: Chesler Naomi C. , Thompson-Figueroa and John , Millburne Ken
Published: May 2004

Background: Robust techniques for characterizing the biomechanical properties of mouse pulmonary arteries will permit exciting gene-level hypotheses regarding pulmonary vascular disease to be tested in genetically engineered animals. In this paper, we present the first measurements of the biomechanical properties of mouse pulmonary arteries. Method of Approach: In an isolated vessel perfusion system, transmural pressure, internal diameter and wall thickness were measured during inflation and deflation of mouse pulmonary arteries over low (5–40 mmHg) and high (10–120 mmHg) pressure ranges representing physiological pressures in the pulmonary and systemic circulations, respectively. Results: During inflation, circumferential stress versus strain showed the nonlinear “J”-shape typical of arteries. Hudetz’s incremental elastic modulus ranged from 27±13kPan=7 during low-pressure inflation to 2,700±1,700kPan=9 during high-pressure inflation. The low and high-pressure testing protocols yielded quantitatively indistinguishable stress-strain and modulus-strain results. Histology performed to assess the state of the tissue after mechanical testing showed intact medial and adventitial architecture with some loss of endothelium, suggesting that smooth muscle cell contractile strength could also be measured with these techniques. Conclusions: The measurement techniques described demonstrate the feasibility of quantifying mouse pulmonary artery biomechanical properties. Stress-strain behavior and incremental modulus values are presented for normal, healthy arteries over a wide pressure range. These techniques will be useful for investigations into biomechanical abnormalities in pulmonary vascular disease.
Vesicular Glutamate Transporters 1 and 2 Target to Functionally Distinct Synaptic Release Sites
Authors: Fremeau Robert T. , Kam Kaiwen , Qureshi Tayyaba , Johnson Juliette , Copenhagen David R. , Storm-Mathisen Jon , Chaudhry Farrukh A. , Nicoll Roger A. , Edwards Robert H.
Published: May 2004

Vesicular glutamate transporters (VGLUTs) 1 and 2 show a mutually exclusive distribution in the adult brain that suggests specialization for synapses with different properties of release. Consistent with this distribution, inactivation of the VGLUT1 gene silenced a subset ofexcitatory neurons in the adult. However, the same cell populations exhibited VGLUT1-independent transmission early in life. Developing hippocampal neurons transiently coexpressed VGLUT2 and VGLUT1 at distinct synaptic sites with different short-term plasticity. The loss of VGLUT1 also reduced the reserve pool of synaptic vesicles. Thus, VGLUT1 plays an unanticipated role in membrane trafficking at the nerve terminal.
Signal Transduction Cascade between EvgA/EvgS and PhoP/PhoQ Two-Component Systems of
Escherichia coli
Authors: Eguchi Yoko , Okada Tadashi , Minagawa Shu , Oshima Taku , Mori Hirotada , Yamamoto Kaneyoshi , Ishihama Akira , Utsumi Ryutaro
Published: May 2004

Transcriptional analysis of a constitutively active mutant of the EvgA/EvgS two-component system of
Escherichia coli
resulted in enhanced expression of 13 PhoP/PhoQ-regulated genes,
crcA
,
hemL
,
mgtA
,
ompT
,
phoP
,
phoQ
,
proP
,
rstA
,
rstB
,
slyB
,
ybjG
,
yrbL
, and
mgrB
. This regulatory network between the two systems also occurred as a result of overproduction of the EvgA regulator; however, enhanced transcription of the
phoPQ
genes did not further activate expression of the PhoP/PhoQ-regulated genes. These results demonstrated signal transduction from the EvgA/EvgS system to the PhoP/PhoQ system in
E. coli
and also identified the genes that required the two systems for enhanced expression. This is one example of the intricate signal transduction networks that are posited to exist in
E. coli
.
Identification of an Uptake Hydrogenase Required for Hydrogen-Dependent Reduction of Fe(III) and Other Electron Acceptors by
Geobacter sulfurreducens
Authors: Coppi Maddalena V. , O'Neil Regina A. , Lovley Derek R.
Published: May 2004

Geobacter sulfurreducens
, a representative of the family
Geobacteraceae
that predominates in Fe(III)-reducing subsurface environments, can grow by coupling the oxidation of hydrogen to the reduction of a variety of electron acceptors, including Fe(III), fumarate, and quinones. An examination of the
G. sulfurreducens
genome revealed two operons,
hya
and
hyb
, which appeared to encode periplasmically oriented respiratory uptake hydrogenases. In order to assess the roles of these two enzymes in hydrogen-dependent growth, Hya- and Hyb-deficient mutants were generated by gene replacement. Hyb was found to be required for hydrogen-dependent reduction of Fe(III), anthraquinone-2,6-disulfonate, and fumarate by resting cell suspensions and to be essential for growth with hydrogen and these three electron acceptors. Hya, in contrast, was not. These findings suggest that Hyb is an essential respiratory hydrogenase in
G. sulfurreducens
.
Regulation of Photosynthesis Genes in
Rubrivivax gelatinosus
: Transcription Factor PpsR Is Involved in both Negative and Positive Control
Authors: Steunou Anne-Soisig , Astier Chantal , Ouchane Soufian
Published: May 2004

Induction of biosynthesis of the photosystem in anoxygenic photosynthetic bacteria occurs when the oxygen concentration drops. Control of this induction takes place primarily at the transcriptional level, with photosynthesis genes expressed preferentially under anaerobic conditions. Here, we report analysis of the transcriptional control of two photosynthesis promoters,
pucBA
and
crtI
, by the PpsR factor in
Rubrivivax gelatinosus
. This was accomplished by analyzing the photosystem production in the wild type and in the PPSRK (
ppsR
::Km) mutant grown under anaerobic and semiaerobic conditions and by assessing the β-galactosidase activity of
lacZ
transcriptionally fused to promoters possessing the putative PpsR-binding consensus sequences. It was found that under semiaerobic conditions, inactivation of the
ppsR
gene resulted in overproduction of carotenoid and bacteriochlorophyll pigments, while the production of LH2 was drastically reduced. The β-galactosidase activity showed that, in contrast to what has been found previously for
Rhodobacter
species, PpsR acts in
R. gelatinosus
as an aerobic repressor of the
crtI
gene while it acts as an activator for the expression of
pucBA
. Inspection of the putative PpsR-binding consensus sequences revealed significant differences that may explain the different levels of expression of the two genes studied.
Involvement of the C-Terminal Extension of the α Polypeptide and of the PucC Protein in LH2 Complex Biosynthesis inRubrivivax gelatinosus
Authors: Steunou Anne-Soisig , Ouchane Soufian , Reiss-Husson Françoise , Astier Chantal
Published: May 2004

The facultative phototrophic nonsulfur bacteriumRubrivivax gelatinosusexhibits several differences from other species of purple bacteria in the organization of its photosynthetic genes. In particular, thepucoperon contains only thepucBandpucAgenes encoding the β and α polypeptides of the light-harvesting 2 (LH2) complex. Downstream of thepucBAoperon is thepucCgene in the opposite transcriptional orientation. The transcription ofpucBAandpucChas been studied. NopucCtranscript was detected either by Northern blotting or by reverse transcription-PCR analysis. The initiation site ofpucBAtranscription was determined by primer extension, and Northern blot analysis revealed the presence of two transcripts of 0.8 and 0.65 kb. The half-lives of both transcripts are longer in cells grown semiaerobically than in photosynthetically grown cells, and the small transcript is the less stable. It was reported that the α polypeptide, encoded by thepucAgene, presents a C-terminal extension which is not essential for LH2 function in vitro. The biological role of this alanine- and proline-rich C-terminal extension in vivo has been investigated. Two mutants with C-terminal deletions of 13 and 18 residues have been constructed. Both present the twopucBAtranscripts, while their phenotypes are, respectively, LH2+and LH2−, suggesting that a minimal length of the C-terminal extension is required for LH2 biogenesis. Another important factor involved in the LH2 biogenesis is the PucC protein. To gain insight into the function of this protein inR. gelatinosus, we constructed and characterized a PucC mutant. The mutant is devoid of LH2 complex under semiaerobiosis but still produces a small amount of these antennae under photosynthetic growth conditions. This conditional phenotype suggests the involvement of another factor in LH2 biogenesis.
Genome-Wide Analysis of Lipoprotein Expression in
Escherichia coli
MG1655
Authors: Brokx Stephen J. , Ellison Michael , Locke Troy , Bottorff Drell , Frost Laura , Weiner Joel H.
Published: May 2004

To
gain insight into the cell envelope of
Escherichia coli
grown
under aerobic and anaerobic conditions, lipoproteins were examined by
using functional genomics. The mRNA expression levels of each of these
genes under three growth conditions—aerobic, anaerobic, and
anaerobic with nitrate—were examined by using both Affymetrix
GeneChip
E. coli
antisense genome arrays and
real-time PCR (RT-PCR). Many genes showed significant changes in
expression level. The RT-PCR results were in very good
agreement with the microarray data. The results of this study represent
the first insights into the possible roles of unknown lipoprotein genes
and broaden our understanding of the composition of the cell envelope
under different environmental conditions. Additionally, these data
serve as a test set for the refinement of high-throughput bioinformatic
and global gene expression
methods.
Influence of species proportion and timing of establishment on stem quality in mixed red alder  Douglas-fir plantations
Authors: Grotta Amy T , Gartner Barbara L , Radosevich Steven R
Published: May 2004

The relationships among stand structure, Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) branch characteristics, and red alder (Alnus rubra (Bong.)) stem form attributes were explored for 10- to 15-year-old trees growing in mixed Douglas-fir  red alder plantations. Treatments included a range of species proportions, and red alder was either planted simultaneously with Douglas-fir or after 5 years. Both replacement effects (total stand density held constant) and additive effects (stand density doubled) of competition were considered. When the two species were planted simultaneously and red alder proportion was low, red alder trees had low crown bases and much stem defect (lean, sweep, and multiple stems). Douglas-fir grew slowly when the two species were planted simultaneously. When red alder planting was delayed, species proportion did not affect red alder stem form, and height to the base of the Douglas-fir live crown decreased with increasing red alder proportion. Doubling Douglas-fir density increased the height to the base of the Douglas-fir live crown; however, doubling stand density by adding red alder did not affect Douglas-fir crown height. Douglas-fir lumber coming from mixed stands may be inferior because of the changes in knot characteristics associated with these different patterns of crown recession. In stands with a low proportion of red alder, red alder product recovery may be compromised because of the stem defects described above.