bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heat and water transfer in a rotating drum containing solid substrate particles
Authors: Schutyser M. A. I. , Weber F. J. , Briels W. J. , Rinzema A. , Boom R. M. 
Published: March 2003

AbstractIn previous work we reported on the simulation of mixing behavior of a slowly rotating drum for solid‐state fermentation (SSF) using a discrete particle model. In this investigation the discrete particle model is extended with heat and moisture transfer. Heat transfer is implemented in the model via interparticle contacts and the interparticle heat transfer coefficient is determined experimentally. The model is shown to accurately predict heat transfer and resulting temperature gradients in a mixed wheat grain bed. In addition to heat transfer, the addition and subsequent distribution of water in the substrate bed is also studied. The water is added to the bed via spray nozzles to overcome desiccation of the bed during evaporative cooling. The development of moisture profiles in the bed during spraying and mixing are studied experimentally with a water‐soluble fluorescent tracer. Two processes that affect the water distribution are considered in the model: the intraparticle absorption process, and the interparticle transfer of free water. It is found that optimum distribution can be achieved when the free water present at the surface of the grains is quickly distributed in the bed, for example, by fast mixing. Alternatively, a short spraying period, followed by a period of mixing without water addition, can be applied. The discrete particle model developed is used successfully to examine the influence of process operation on the moisture distribution (e.g., fill level and rotation rate). It is concluded that the extended discrete particle model can be used as a powerful predictive tool to derive operating strategies and criteria for design and scale‐up for mixed SSF and other processes with granular media. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 82: 552–563, 2003.
Theoretical distribution of truncation lengths in incremental truncation libraries
Authors: Ostermeier Marc 
Published: March 2003

AbstractIncremental truncation is a method for constructing libraries of every one base pair truncation of a segment of DNA. Incremental truncation libraries can be created using a time‐dependent nuclease method or through the incorporation of α‐phosphothioate dNTPs by PCR or by primer extension (THIO(pcr) truncation and THIO(extension) truncation, respectively). Libraries created by the fusion of two truncation libraries, known as ITCHY libraries, can be created using the above methods or by the incremental truncation‐like method SHIPREC. Knowing and being able to tailor the distribution of truncations in incremental truncation, ITCHY and SHIPREC libraries would be beneficial for their use in protein engineering and other applications. However, the experimental determination of the distributions would require extensive, cost‐prohibitive, DNA sequencing to obtain statistically relevant data. Instead, a theoretical prediction of the distributions was developed. Time‐dependent incremental truncation libraries had the most uniform distribution of truncation lengths, but were biased against longer truncations. Essentially uniform distribution over the desired truncation range (from zero to Nmax base pairs) required that truncations be prepared up to at least 1.2–1.5 Nmax. THIO(pcr) and THIO(extension) truncation libraries had a very nonuniform distribution of truncation lengths with a bias against longer truncations. Such nonuniformity could be significantly diminished by decreasing the incorporation rate of αS‐dNTPs but at the expense of having a large fraction of the DNA truncated beyond the desired range or completely degraded. ITCHY libraries created using time‐dependent truncation had the most uniform distribution of possible fusions and had the highest fraction of the library being parental‐length fusions. However, the distribution of parental‐length fusions was biased against fusions near the beginning/ends of genes unless the truncation libraries are prepared with a uniform distribution up to Nmax. In contrast, SHIPREC libraries and THIO(pcr) ITCHY libraries, by the very nature of the nonuniform distributions of the truncated DNA, are ensured of having a uniform distribution of fusion points in parental‐length fusions. This comes at the expense of having a smaller fraction of the library being parental‐length fusions; however, this limitation can be overcome by performing size selection on the library. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 82: 564–577, 2003.
Profiles of the parents of adolescent CSA perpetrators attending a voluntary outpatient treatment programme in Ireland
Authors: Duane Yvonne , Carr Alan , Cherry Joan , McGrath Kieran , O'Shea Deirdre 
Published: March 2003

AbstractA group of 22 parents of adolescent sexual offenders (PASO) was compared with a group of 19 normal controls (NC) and 10 clinical controls (CC) on demographic, developmental, personal adjustment and family environment variables. The assessment protocol included the General Health Questionnaire‐12, the Culture‐Free Self‐Esteem Inventory, the Child Behaviour Checklist, the Family Assessment Device, the Parent Satisfaction Scale and the Multidimensional Scale of Perceived Social Support. Compared with clinical and normal controls, more parents in the PASO group reported that they had been arrested or charged for a criminal offence; had personally experienced child abuse; and more of their adolescents had experienced child abuse, with emotional abuse being the most common form of abuse for both parents and adolescents. Compared with clinical and normal controls, more adolescents of parents in the PASO group had witnessed parental drug or alcohol abuse and had been placed in care outside their home. While parents in the PASO group did not differ from clinical or normal controls in terms of personal adjustment, their adolescents had significantly more internalizing behaviour problems than normal controls, whereas adolescents of parents in the clinical control group had significantly more externalizing behaviour problems than normal controls. Compared with normal controls, parents in both the PASO and clinical control groups reported more difficulties with general family functioning, roles, affective responsiveness, affective involvement and behaviour control and lower levels of parental satisfaction. However, the groups did not differ significantly in their levels of perceived social support. Copyright © 2003 John Wiley & Sons, Ltd.
Photocrosslinking in Ruthenium‐Labelled Duplex Oligonucleotides
Authors: Lentzen O. , Constant J.‐F. , Defrancq E. , Prévost M. , Schumm S. , Moucheron C. , Dumy P. , Kirsch‐De Mesmaeker A. 
Published: March 2003

AbstractThe formation of a photoadduct between a [Ru(1,4,5,8‐tetraazaphenanthrene)24,7‐diphenylphenanthroline]2+ complex chemically attached to a synthetic oligonucleotide, and a guanine moiety in a complementary targeted single‐stranded DNA molecule was studied for ten 17‐mer duplexes by denaturing gel electrophoresis. This photoadduct formation leads to photocrosslinking of the two strands. The percentage quenching of luminescence of the complex by electron transfer was compared to the resulting yield of photocrosslinked product. This yield does not only depend on the ionisation potential of the guanine bases, which are electron donors, but also on other factors, such as the position of the guanine bases as compared to the site of attachment of the complex. The photocrosslinking yield is higher when the guanine moieties are towards the 3′ end on the complementary strand as compared to the tethering site. Computer modelling results are in agreement with this preference for the 3′ side for the photoreaction. Interestingly, the photocrosslink is not alkali labile. Moreover, a type III exonuclease enzyme is blocked at the position of photocrosslinking.
Substrate Specificity of Mutants of the Hydroxynitrile Lyase from Manihot esculenta
Authors: Bühler Holger , Effenberger Franz , Förster Siegfried , Roos Jürgen , Wajant Harald 
Published: March 2003

AbstractSeveral tryptophan128‐substituted mutants of the hydroxynitrile lyase from Manihot esculenta (MeHNL) are constructed and applied in the MeHNL‐catalyzed addition of HCN to various aromatic and aliphatic aldehydes as well as to methyl and ethyl ketones to yield the corresponding cyanohydrins. The mutants (especially MeHNL‐W128A) are in most cases superior to the wild‐type (wt) enzyme when diisopropyl ether is used as the solvent. Substitution of tryptophan128 by an alanine residue enlarges the entrance channel to the active site of MeHNL and thus facilitates access of sterically demanding substrates to the active site, as clearly demonstrated for aromatic aldehydes, especially 3‐phenoxybenzaldehyde. These experimental results are in accordance with the X‐ray crystal structure of MeHNL‐W128A. Aliphatic aldehydes, surprisingly, do not demonstrate this reactivity dependence of mutants on substrate bulkiness. Comparative reactions of 3‐phenoxybenzaldehyde with wtMeHNL and MeHNL‐W128A in both aqueous citrate buffer and a two‐phase system of water/methyl tert‐butyl ether again reveal the superiority of the mutant enzyme: 3‐phenoxybenzaldehyde was converted quantitatively into a cyanohydrin nearly independently of the amount of enzyme present, with a space‐time yield of 57 g L−1 h−1.
Tools for Design and Control of Industrial Crystallizers – State of Art and Future Needs
Authors: Kramer H.J.M. , Jansens P.J. 
Published: March 2003

AbstractThe design and control of industrial crystallizers continues to be a tremendous challenge. The tendency to move away from base‐chemicals towards fine‐chemicals will give a new impulse to the utilisation of crystallization technology for the separation and the formulation of particulate products. This paper reviews the most recent developments in the design industrial crystallizers and the development of novel crystallization processes. Furthermore it discusses emerging modeling tools needed for a flexible design and operation of crystallizers and crystallization processes that meet rapid changing product yield and specifications. Finally a new approach towards model‐based predictive control of crystallization processes is presented.
In‐Line Monitoring of Crystallization Processes Using a Laser Reflection Sensor and a Neural Network Model
Authors: Giulietti M. , Guardani R. , Nascimento C.A.O. , Arntz B. 
Published: March 2003

AbstractLaboratory‐scale experiments were carried out for measuring the chord length distribution of different particle systems using a laser reflection sensor. Samples consisted of monodisperse, polydisperse and bimodal FCC catalyst and PVC particles of different sizes, ranging from about 20 to 500 μm. The particles were dispersed in water, forming suspensions with solid‐phase mass fractions ranging from ca. 0.2 % until ca. 30 %. The experimental results, consisting of the particle number counting per chord length class, were used in fitting a neural network model for estimating the mass concentration of particles in the suspension and the volume‐based size distribution, eliminating the effects of suspension concentration and particle shape. The results indicate the feasibility of using such a model as a software sensor in crystallization processes monitoring.
In‐line Control and Automatic Management of Industrial Crystallizations using NIR Technique
Authors: Vaccari G. , Tamburini E. , Tosi S. , Sgualdino G. , Bernardi T. 
Published: March 2003

AbstractThe correct and automatic management of a crystallization process would require the knowledge, in real‐time, of the amount of the crystals present in the magma, the supersaturation of the mother liquor, the growth kinetics etc. To solve this problem, we tried to utilize the NIR (Near Infra‐Red Spectroscopy) technique using a probe submerged in the growing magma. The first results obtained following the cooling crystallization of sucrose are presented and discussed.
A Micro‐Mechanical Model for the Rate of Aggregation during Precipitation from Solution
Authors: Liew T.L. , Barrick J.P. , Hounslow M.J. 
Published: March 2003

AbstractOur group has proposed [1,2] that the rate of aggregation between crystals in a supersaturated solution depends on the rate of collision and on the probability of that collision surviving. It has been suggested that the probability, or efficiency, depends on the strength of the newly formed neck between the crystals and the hydrodynamic force acting to pull them apart. That strength has been quantified by assuming that the crystals first touch at a point and thus the area of the neck increases with the square of time. In this paper, over 400 data points were considered for calcium oxalate monohydrate (COM), and more than 250 for calcite, relating the rate of aggregation in a stirred tank to the stirrer speed, the supersaturation and the particle size and show that the existing model cannot account for the relationship seen. It is proposed instead that the first contact between crystals lies along a line and thus the area of the neck grows linearly with time. A dimensionless strength formulated in this way is able to account for the dependence seen.
Modeling Growth Rate Dispersion in Industrial Crystallizers
Authors: Westhoff G.M. , van de Rijt J. , Kramer H.J.M. , Jansens P.J. 
Published: March 2003

AbstractThe phenomenon of healing appears to be a plausible explanation for the growth rate dispersion observed in many industrial crystallizers. In this paper a growth model is postulated, which describes the healing of plastically deformed attrition fragments. The rate of healing is assumed to be inversely proportional to the initial strain and to the rate of change of either the length, the area, or the volume of the crystal. The validity of the proposed model is verified by the simulation of growth of the smallest crystals (L0) in time in a growth experiment for specific combinations of the model parameters. In addition, the applicability of the proposed model is evaluated through simulations of steady state experimental data obtained in a 75‐liter Draft Tube (DT) crystallizer. It is concluded that the proposed model is able to fit reasonably well the experimental crystal size distribution. The model predicts the existence of a ‘dead time’ during which attrition fragments with large initial strain do not grow and which may last several residence times.
Derivation of Supersaturation and Nucleation Flux in a Stirred Tank from Tracer Concentration Measurements
Authors: Fall A. , Lecoq O. , David R. 
Published: March 2003

AbstractThe PLIF (Planar Laser Induced Fluorescence Technique) method is applied to determine experimentally the field of supersaturation in a separate double jet reactive precipitator from the local instantaneous field of concentrations of an inert tracer. The nucleation flux in the mixing region is derived.
Kinetic Characteristics of Amino Acid Salt Crystallization in Methanol‐Water System
Authors: Hasznos‐Nezdei M. , Liszi I. , Lakatos B.G. 
Published: March 2003

AbstractNucleation and growth mechanisms and kinetics of crystals of an amino acid salt were investigated in a methanol‐water system by measuring and evaluating the induction time as a function of the supersaturation ratio and temperature in batch salting out crystallization experiments. Discrimination between the possible crystallization mechanisms, and estimation of the kinetic parameters were carried out using nonlinear parameter identification. The results concerning the growth mechanism obtained were checked additionally by measuring the induction time as a function of number density of seed crystals.
Studies into the Internal Structure of Gibbsite Agglomerates
Authors: Ilievski D. , Austin P. , Whittington B. 
Published: March 2003

AbstractThis paper outlines techniques that have been developed or adapted to characterise the internal structure of gibbsite agglomerates and their application to selected laboratory gibbsite sample. The specific structural properties investigated include the quantification of gibbsite voidage (Floc Density Analyser), determination of relative changes in gibbsite crystal orientation (Raman spectroscopy and electron backscattered diffraction) and location of the cement binding agglomerated gibbsite particles (Raman spectroscopy, charge contrast and orientation contrast imaging). This paper also describes the use of Kikuchi patterns for investigating crystal orientation at a point and as a tool to assess if a particle is a single crystal or an agglomerate or a multi‐fold twin.
Herausforderungen für die Lehre am Beispiel der mechanischen Verfahrenstechnik
Authors: Peukert W. , Schmid H.‐J. 
Published: March 2003

AbstractRasche technologische Entwicklungen haben für Chemieingenieure bzw. Verfahrenstechniker neue Beschäftigungsmöglichkeiten eröffnet, wodurch sich zusätzliche Anforderungen an die Ausbildung ergeben. Der vorliegende Beitrag beschreibt die Lösungsansätze im Fachgebiet der Partikeltechnik: Es findet eine noch stärkere Betonung der Grundlagen statt, wobei Beispiele aus klassischen und neuen Anwendungen exemplarisch vertieft werden. Kernpunkt des Curriculums sind die Produkteigenschaften. Besonderes Gewicht wird außerdem auf die Betrachtung ganzer Prozesse gelegt. Die Vorlesungen sind in drei Ebenen strukturiert: Grundlagen, Grundoperationen und Prozesse/Anwendungen. Methodisch wird ein zweifacher Ansatz verfolgt: Die Lehre der grundlegenden Fakten wird ergänzt durch eine aktive Teilnahme der Studenten, insbesondere bei der Erarbeitung von Beispielen und in Labor‐ bzw. Rechnerpraktika. Durch eine ganzheitliche Sicht der Universitätsausbildung sollen auch „soft skills“ gefördert werden.
Herstellung rekombinanter Proteine mit Pichia pastoris in integrierter Prozessführung
Authors: Cornelissen G. , Bertelsen H.‐P. , Hahn B. , Schultz M. , Scheffler U. , Werner E. , Leptien H. , Krüß S. , Jansen A.‐K. , Gliem T. , Hielscher M. , Wilhelm B.‐U. , Sowa E. , Radeke H.H. , Luttmann R. 
Published: March 2003

AbstractNo abstracts.
A Phase II trial of green tea in the treatment of patients with androgen independent metastatic prostate carcinoma
Authors: Jatoi Aminah , Ellison Neil , Burch Patrick A. , Sloan Jeff A. , Dakhil Shaker R. , Novotny Paul , Tan Winston , Fitch Tom R. , Rowland Kendrith M. , Young Charles Y. F. , Flynn Patrick J. 
Published: March 2003

AbstractBACKGROUNDRecent laboratory and epidemiologic studies have suggested that green tea has antitumor effects in patients with prostate carcinoma. This Phase II trial explored green tea's antineoplastic effects in patients with androgen independent prostate carcinoma.METHODSThis study, which was conducted by the North Central Cancer Treatment Group, evaluated 42 patients who were asymptomatic and had manifested, progressive prostate specific antigen (PSA) elevation with hormone therapy. Continued use of luteinizing hormone‐releasing hormone agonist was permitted; however, patients were ineligible if they had received other treatments for their disease in the preceding 4 weeks or if they had received a long‐acting antiandrogen therapy in the preceding 6 weeks. Patients were instructed to take 6 grams of green tea per day orally in 6 divided doses. Each dose contained 100 calories and 46 mg of caffeine. Patients were monitored monthly for response and toxicity.RESULTSTumor response, defined as a decline ≥ 50% in the baseline PSA value, occurred in a single patient, or 2% of the cohort (95% confidence interval, 1–14%). This one response was not sustained beyond 2 months. At the end of the first month, the median change in the PSA value from baseline for the cohort increased by 43%. Green tea toxicity, usually Grade 1 or 2, occurred in 69% of patients and included nausea, emesis, insomnia, fatigue, diarrhea, abdominal pain, and confusion. However, six episodes of Grade 3 toxicity and one episode of Grade 4 toxicity also occurred, with the latter manifesting as severe confusion.CONCLUSIONSGreen tea carries limited antineoplastic activity, as defined by a decline in PSA levels, among patients with androgen independent prostate carcinoma. Cancer 2003;97:1442–6. © 2003 American Cancer Society.DOI 10.1002/cncr.11200
Extent of extracapsular spread
Authors: Greenberg Jayson S. , Fowler Robert , Gomez Jose , Mo Vivian , Roberts Dianna , El Naggar Adel K. , Myers Jeffrey N. 
Published: March 2003

AbstractBACKGROUNDExtracapsular spread (ECS) of metastatic squamous cell carcinoma of the head and neck to regional lymph nodes is the most reliable predictor of poor treatment outcomes. Recently, the authors have shown that ECS is significantly associated with higher rates of locoregional recurrence, distant metastasis, and decreased survival in patients with squamous cell carcinoma of the oral tongue (SCCOT). The purpose of this review was to determine if the degree of ECS impacts distant metastasis rates and survival.METHODSTwo hundred sixty‐six patients treated for SCCOT with surgery +/− adjuvant radiotherapy from 1980–1995 were reviewed. The setting was a tertiary referral center. The extent of ECS on histopathologic review of involved lymph nodes was measured from the capsular margin to the farthest perinodal extension in mm. Extent of ECS and the number of pathologic lymph nodes with or without ECS were analyzed for disease‐free interval, survival rates, and distant metastases.RESULTSNo differences in the survival of patients with ECS of ≤ 2 mm or > 2 mm was found (P = 0.92). Patients with both ECS and multiple positive lymph nodes had decreased overall survival (P = 0.0003), disease‐specific survival (P = 0.0005), and a shorter disease‐free interval (P = 0.019) when compared with those with a single positive lymph node with ECS. Those with multiple ECS+ lymph nodes had the worst prognosis (P = 0.001).CONCLUSIONSBased on these findings, the authors recommended that all patients with SCCOT with ECS or multiple positive lymph nodes with or without ECS on pathologic review be considered for clinical trials that intensify regional and systemic adjuvant therapy. Cancer 2003;97:1464–70. © 2003 American Cancer Society.DOI 10.1002/cncr.11202