bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of Two Cracks in a Simply Supported Beam from Minimal Frequency Measurements
Authors: Morassi Antonino , Rollo Matteo
Published: March 2007

This paper presents a diagnostic technique for the identification of two cracks of equal severity in a simply supported beam under flexural vibrations. The crack is simulated by a rotational spring connecting the two adjacent segments ofthe beam. The analysis is based on an explicit expression of the frequency sensi tivity to damage, and the damaged system is considered as a perturbation of the virgin system. By measuring the changes of the first three natural frequencies, it is possible to study the inverse problem—identification of crack location and severity. The inverse problem is ill-posed; namely, even by leaving symmetrical posi tions aside, cracks with different severity in two sets of different locations can produce identical changes in the first three natural frequencies. Numerical results show that if the natural frequencies used as data in iden tification are affected by errors relatively small with respect to the frequency-induced changes, then damage identification leads to satisfactory results.
Robust Control for Structural Systems with Parametric and Unstructured Uncertainties
Authors: Wang Sheng-Guo , Yeh H.Y. , Roschke Paul N.
Published: March 2007

Tall, slender structures and long bridges inherit numerous uncertainties due to model errors, stress calculations, material properties, and load environments and may undergo large forces from natural hazards such as earthquakes and strong wind events. This paper develops a robust active control approach with para metric uncertainty in the system and control input and unstructured uncertainty in the disturbance input ma trices based on an uncertain structural system. A special single-valued decomposition (SVD) is applied to structured uncertain structures. The robust control law provides robust relative stability, an H∞-norm distur bance attenuation, and H2 optimality. The H∞ norm of the transfer function from the external disturbance forces (e.g., earthquake, wind, etc.) to the observed system states is restricted by a prescribed attenuation in dex δ. Preservation of robust H2 optimality of uncertain structural systems is discussed. This paper considers both structured uncertainties and norm-bounded unstructured uncertainties. Numerical simulations that use the robust controller show significant reduction in vibrations.
Numerical Investigation With Rub-Related Vibration in Rotating Machinery
Authors: Lin F. , Schoen M.P. , Korde U.A.
Published: March 2007

Nonlinear behavior of rub-related vibration in rotating machinery is studied with a large number of numerical simulations. A simplified model is used to capture the dynamic response of the rotor when it rubs its housing. It is shown that the model displays rich dynamics, many of which are rather complicated and cannot be captured with linear models. The effects of rotating speed, clearance, damping coefficient, friction coefficient, and boundary stiffness are investigated. The data generated are displayed graphically and explained with the aid of the theory of modem nonlinear dynamics. It is demonstrated that the system goes through an extraordinary route to chaos and that the stretching, contraction, and folding of initial volumes may indicate the existence of a horseshoe map, which plays an important role in creating chaotic phenomena. These results help engineers to optimize the design of rotating machinery, as well as to develop sensitive monitoring/diagnosis systems assessing machinery conditions.
Response Statistics of a Beam-Mass Oscillator Under Combined Harmonic and Random Excitation
Authors: Ekwaro-Osire Stephen , Ertas Atila
Published: March 2007

In the present study, the response statistics of a beam-mass oscillator under combined harmonic and random excitation were investigated. The Gaussian and non-Gaussian closure schemes, in conjunction with the stochastic averaging method, were used to solve for the mean square response. The influence of the oscillator parameters on the response statistics was studied. The harmonic component of the excitation was observed to manifest itself, as an oscillation, in the steady-state mean square response. Results obtained showed that the non-Gaussian solution yields higher steady-state mean square responses than those obtained from the Gaussian solution. It was further shown that the harmonic time-varying properties of the oscillator are preserved by omitting the time-averaging in the stochastic averaging procedure.
Balancing Model Order Reduction Technique for Descriptor-Like Systems
Authors: Ansary Omid
Published: March 2007

This paper presents the balancing model order reduction technique in the context of a descriptor- like system representation, which exhibits special structural properties. This is done by integration of these properties into the conventional balancing model order reduction method. An example is given to illustrate the tractability and the application of the proposed technique.
Use of a Flexible Internal Support to Suppress Vibrations of a Rotating Shaft Passing Through a Critical Speed
Authors: Suherman Surjani , Plaut Raymond H.
Published: March 2007

As is widely known, large vibrations may occur when a rotating shaft passes through one of its critical speeds. To suppress these large motions, it may be possible to modify the system as it is accelerating or decelerating in such a way as to avoid this resonance phenomenon. This is accomplished with the use of a flexible internal support that can be activated or deactivated during run-up or run-down of the system. The shaft has an unbalanced disk, and the nonstationary analysis includes gravitational forces and internal and external damping. The system is driven by a motor that may be nonideal (with a limited power supply) or ideal. Although transient motions are caused when the system stiffness is changed, the resulting maximum displacement may be significantly less than that of the original system passing through a critical speed.
Process Model-Based Force-Controlled Chamfering and Deburring
Authors: Wiens Gloria J. , Musunur Laxmi P. , Walker Craig W.
Published: March 2007

During the past decade, the manufacturing industry has experienced a dramatic increase in employ ees suffering from repetitive motion injuries. Hence, a renewed interest in the use of passive and active mi cromanipulators for automating deburring and finishing applications has arisen. In this paper, a new approach for the control of active micromanipulators used for automated edge chamfering and deburring applications is presented. The approach implements a process model into the controller's correlations and logic mod ule to provide a basis for determining adjustments in the controlled force levels. Based on sensor data and system/process knowledge, the module makes decisions on what corrective action, if any, is required to ensure burr removal and production of the desired chamfer. Both simulation and experimental results are presented, demonstrating the effectiveness of this new controller design.
Design-Oriented Ductility Bound of a Plane Frame Under Seismic Loading
Authors: Takewaki Izuru
Published: March 2007

The purpose of this paper is to propose an approximate upper bound of member ductility factors of a plane building frame under a set of spectrum-compatible earthquakes. The acceleration response spectrum is assumed to be a nonincreasing function of period for a constant damping ratio and a nonincreasing function of damping ratio for a constant period. Most of the previously proposed design acceleration response spectra appear to satisfy these assumptions except in a narrow range of quite small periods. The present study shows that the upper bound (design-oriented upper bound) of member ductility factors can be drawn only when combined with a design method for almost uniform ductility, which is recognized in general to be desirable for avoiding damage concentration. It is shown that the second assumption on the acceleration response spectrum and neglect of additional damping in the equivalent linear model enable one to derive a narrower upper bound on member ductility factors. Inelastic time-history response analyses are performed to investigate the accuracy of the upper bounds and to examine the validity of an equivalent linearization technique.
Controlled Dynamics of Flexible Orbiting Tethered Systems: Analysis and Experiments
Authors: Modi Vinod J. , Pradhan Satyabrata , Misra Arun K.
Published: March 2007

The equations of motion for a class of tethered satellite systems (TSS) undergoing planar motion in a Keplerian orbit are derived using the Lagrangian procedure. The system consists of a rigid platform from which a point mass subsatellite can be deployed or retrieved by a flexible tether. The model incorporates an offset of the tethered attachment point from the platform center of mass and its time dependent variation. The feedback linearization technique (FLT) is used to design the attitude regulator. A hybrid strategy, using thruster and offset schemes, is used for regulating the tether swing, and momentum gyros are employed for the platform control. The offset strategy is also used for active control of the tether flexibility during stationkeeping in conjunction with the thruster-based attitude controller. Finally, effectiveness of the offset- based attitude controller is demonstrated through ground-based experiments, thus substantiating the trends predicted by the numerical simulations.
Stability Analysis of Nonlinear Parametric and Coulomb Control Systems
Authors: Gupta H. , Soong T.T. , Singh T.
Published: March 2007

Stability analysis of nonlinear control systems using Lypunov's direct method is reported in this paper. A general nonlinear controlled system and two different types of controllers are examined for stability analysis. The first category is the parametric controller. Importance of parametric controllers is illustrated through examples of various engineering systems. A general control algorithm is derived, and stability of the closed-loop system is examined. Stability under small external disturbances is also examined. The second category of controllers examined in this paper is the Coulomb-type controllers. Stability analysis is performed using Lypunov's direct method. Stability under a general forcing excitation is examined for linear systems with Coulomb controllers.
Managed Care and Mental Health Services: How We Got to Where We Are
Authors: Mohr Wanda K.
Published: March 2007

In September 1997, the NationalAlliance for the Mentally Ill issued a national report card asserting that managed care companies are falling short of their promise to deliver high-quality care to people with mental illnesses. This article traces how mental health care has evolvedfrom the overbuilding of psychiatric facilities in the mid and late 1980s to a situation in which millions of mentally ill Americans cannot receive adequate care. It traces events that led to the unprecedented boom in psychiatric care through the 1980s to the place where health care reform has evolved. The disparity between insur ance coverage of mental health care services and general medical care services is dis cussed, and the legislative outcome of recent mental health reform is described. Finally, implications for nursing and recommendations for action are considered. (J Am Psychiatr Nurses Assoc [1998]. 4, 153-161)
You-Attitude: A Linguistic Perspective
Authors: Rodman Lilita
Published: March 2007

You-attitude is a pedagogically convenient cover term that subsumes considerable complexity, both with respect to the text effects it may include and the text charac teristics that create these effects. Some of the insights on politeness, tact, and def erence found in the work of Brown and Levinson, Leech, and Fraser and Nolen can help provide guidelines for assessing how important a you-attitude may be in writing about a particular real-world situation, and case grammar and information structure can inform strategies to enhance the expression of a you-attitude. Rather than being a binary variable, you-attitude appears to be gradable, and an infor mal student assessment of the you-attitude expressed in ten versions of the same passage suggests that the various strategies for enhancing the you-attitude conveyed by a text appear to have a cumulative effect, so that a greater sense of you-attitude is created when more strategies are used.
A Short Classroom Unit, but a Significant Improvement, in Listening Ability
Authors: Means Thomas L. , Klein Gary S.
Published: March 2007

The purpose of this study was to determine if a unit on listening that consumes little class time would signifi cantly increase listening skills. This research design was basically pretest/treatment/posttest. Excluding the pre- and posttest, the treatment takes only 80 classroom min utes. The Watson-Barker Listening Test—Video Version was used as the measurement instrument. The data revealed that the average listening skills of participants increased over 21 %. The greatest improvement (over 40%) took place in two listening skill areas—evaluating mes sage content and understanding meaning in conuersation. A significant improvement (over 20%) occurred in under standing and remembering lectures.
Challenging Students to Respond to Multicultural Issues: The Case-Study Approach
Authors: Sharp Helen M.
Published: March 2007

Business communication and technical writing students face a new workplace challenge: responding to problems that reflect a multicultural dimension and involve business- people whose perspectives, values, and traditions are not Western. Case studies are a good teaching strategy to introduce multicultural issues in business communication. Case studies involve students in group settings and demand both problem-solving and human-relations skills. Adding discussion questions to case-study problems prompts student responses, and assigning a follow-up progress report or memorandum ties the case-study reviews to course goals. This article includes both a description of the assignment and two timely case-study samples.
Voice-Graded Business Communication Documents
Authors: Van Horn-Christopher Doris A.
Published: March 2007

Business communication instructors are often overwhelmed by the task of grading writing assignments. Instructors of writing are often frustrated by the complexities of the critiquing process. This article explores the benefits of using a uoice-graded writing approach which offers instructors an opportunity to engage in virtual office critiquing of student assignments.
Using the Internet in Written Business Communication
Authors: Quible Zane K. , Ray Eric J.
Published: March 2007

The Internet already has become a pervasive force in our society, and projections are that it will continue to become even more so in the future. We educators need to be sure we are preparing our students adequately to use the rich resources found on the Internet. The purpose of this article is to help business communication instructors become more familiar with the Internet and to discuss ways its use- through several scenarios - can be incorporated into writ ten business communication courses.
Business Communication Competencies Needed by Employees as Perceived by Business Faculty and Business Professionals
Authors: Waner Karen K.
Published: March 2007

Implementation of total quality management and continu ous process improvement require validation of competencies by an institution's customers. This study was designed to determine if business faculty and business professionals perceive (a) business writing skills, (b) oral/interpersonal skills, (c) basic English skills, and (d) other business com munication abilities with the same degree of importance. Four one-way analyses of variance revealed no significant difference between 35 business professionals and 30 busi ness faculty concerning the four areas. However, when the 50 competencies within the four areas were ranked, some visible differences occurred in using the telephone and intercom, asking questions, and applying confidentiality.
International Business Writing Projects: Learning Content Through Process
Authors: Ranney Frances J. , McNeilly Kevin M.
Published: March 2007

A project undertaken by members of the marketing and English departments in a midwestern university incorporates writing assignments into an intro ductory course in international business. This discussion of course goals and writing projects shows that attention to writing can increase the amount of time students devote to learning course content.
Job-Refusal Letters: Readers' Affectiue Responses to Direct and Indirect Organizational Plans
Authors: Smith Gwendolyn N. , Nolan Rebecca F. , Yong Dai
Published: March 2007

The affective responses of readers to job-refusal letters using direct and indirect approaches were investigated. Subjects were requested to rate organizational plan on 19 dependent measures. Results indicated that the direct job-refusal letter was preferred. It was viewed as more efficient, valuable and straightforward than the indirect approach. These findings are in conflict with current literature favoring the indirect approach for conveying negative information.
The Communication Audit: A Framework for Teaching Management Communication
Authors: Shelby Annette N. , Lamar Reinsch N.
Published: March 2007

This article describes a communication audit project used in a graduate-level management communication course. We review some of the literature con cerning communication audits, explain why and how we use an audit in our classes, and describe specific audit-related assignments. While a challenging assignment both for student and professor, the audit is—in our judgment— clearly worth the effort.
Corporate Advisory Boards, Portfolio Assessment, and Business and Technical Writing Program Development
Authors: Dillon w. Tracy
Published: March 2007

This article advocates student learning portfolios as an effective assessment technique and explains how instructors and administrators can devise a process that involves community partners in assessing student performance. Having community experts judge a student portfolio contest helps faculty identify standards for success that can inform decision making about course content and program offerings. The article discusses how to gain and sustain community involvement in program assessment and describes how portfolio assessment led to the creation of a technical and business writing advisory board at an urban university.
Formats for the Citation of Electronic Sources in Business Writing
Authors: Guffey Mary Ellen
Published: March 2007

Many business researchers today are puzzled when they attempt to construct electronic references to cite sources used in their writing. The most recent edi tions of both the Publication Manual of the American Psychological Associa tion and the MLA Handbook for Writers of Research Papers were published before today's most widely used Internet protocols were introduced: This arti cle presents APA and MLA guides for formatting electronic references. The guides, intended as handouts for students, illustrate typical business communi cation uses.
"Dressing Down" in the Business Communication Curriculum
Authors: McPherson William
Published: March 2007

Corporate America is changing the way it dresses. Students who are preparing for careers in business should be aware of this change, because dress-down days are becoming a part of American corporate culture. Casual dressing is popular, and people-friendly companies are capitalizing on its popularity. This article discusses this corporate trend and offers discussion on the need to include this concept in the business communications curriculum.
Student Attitudes Toward Written, Oral, and E-mail Communication
Authors: Merrier Patricia A. , Dirks Ruthann
Published: March 2007

Business communication students at two midwestern universities were polled on the first day of the 1995 spring term to determine their (1) written com naunication assignment likes Idislikes; (2) oral communication assignment likes/dislikes; (3) experience using e-mail; and (4) attitudes toward written, oral, and e-mail communication. The 144 respondents viewed oral communi cation less positively than they did either written or e-mail communication. Significant differences were found among overall ratings for oral, written, and e-mail communication. In addition, students with prior e-mail experience gave significantly higher ratings to it and to oral communication than did those who had not used e-mail.
Listening Competency in the Workplace: A Model for Training
Authors: Cooper Lynn O.
Published: March 2007

Listening is a desirable skill in organizational settings; good listening can improve worker productivity and satisfaction. The challenge facing consul tants is how to train employees to be competent listeners. Although much research in listening has taken place over the last few years, little of that research addresses workplace listening directly and much is based on false assumptions: that listening is a unitary concept, that listening is a cognitive rather than behavioral skill, and that listening is a linear act. In a 10-year study, we developed a model of organizational listening competency that does apply directly to the workplace. It provides a basis for assessing listening abil ity largely through the observations of co-workers. The model emphasizes two effective behaviors: accuracy, that is, confirming the message sent; and sup port, that is, affirming the relationship between the speaker and the listener: This model serves as an effective basis for improving workplace listening, both through formal training programs and through individual workers' own efforts.
Navigating the Web with a Typology of Corporate Uses
Authors: Hoger Elizabeth A. , Cappel James J. , Myerscough Mark A.
Published: March 2007

Many business communication teachers are grappling with ways to use the rich potential of the WorldWide Web. A categorization or typology of sites provides students with a tool to explore the Web systematically and attentively. The typology discussed in this article divides corporate sites into five cate gories depending on purpose: marketplace awareness and promotion, cus tomer support, sales, advertising, and electronic information services. Armed with this typology, students analyze sites as examples of business communica tion. Based on this analysis, they develop a collaborative oral presentation.
Contexting Koreans: Does the High/Low Model Work?
Authors: Thomas Jane
Published: March 2007

South Korea is assumed to be a high-context culture with extensive shared information and an emphasis on relationships in doing business. The follow ing study reported here tests this assumption and illustrates similarities and differences between Korean and American writers in an attempt to document language differences between high- and low- context societies. Data in the texts studied did not confirm the high/low contextfeatures expected. South Korean texts showed more similarities to than differences from the American texts, and the language features found suggest a more complex context situa tion than the high/low context model may be able to accommodate.
Using Practitioners' Viewpoints to Improve Accounting Students' Communications Skills
Authors: Nellermoe Donald A. , Weirich Thomas R. , Reinstein Alan
Published: March 2007

The accounting profession has recognized the importance of emphasizing written and oral communications skills in the accounting curriculum. Innovations in tech nology have greatly enhanced educators' abilities to incorporate instruction in such skills. A survey of practitioners indicates strong agreement with the new writing requirements of the CPA exam. In addition, they endorse the use of information technology in preparing documents based on specific models and prescribed criteria.
Note. Effect of trisodium phosphate on mesophilic and psychrotrophic bacterial flora attached to the skin of chicken carcasses during refrigerated storage Nota. Efecto del fosfato trisódico en los microorganismos mesófilos y psicrotrofos presentes en la piel de canales de pollo durante su almacenamiento en refrigeración
Authors: Capita R. , Alonso-Calleja C. , García Arias M.T. , Moreno B. , García-Fernández M.C.
Published: March 2007

The potential for using trisodium phosphate (TSP) to reduce mesophilic and psychrotrophic popula tions on the skin of chicken carcasses was explored. Skin samples were immersed in sterile tap water (control) or an 8%, 10% or 12% solution of TSP at 20 °C for 15 min. Surface pH values and mesophilic and psychrotrophic plate counts were determined after 0, 1, 3 and 5 days of storage at 2° C. After washing, bacterial populations were significantly smaller in the samples treated with TSP than in the controls. The concentration of the TSP solution was a significant factor in reducing the populations of the bacteria on chicken skin. Before storage, the reduction in the presence of bacteria achieved in treated samples with respect to controls ranged between 0.95 log10 cycles and 1.78 log10 cycles in the case of mesophilic microorganisms, and 0.92 log10 cycles and 1.94 log10 cycles in the case of psychrotrophic strains. These differences between the concentrations of bacteria in samples immersed in water and those treated with TSP increased over time, ranging from 2.35 log 10 cycles to 3.08 log10 cycles (mesophilic microorganisms), and from 2.79 log10 cycles to 4.09 log10 cycles (psychrotrophic microorganisms) on day 5 of storage. The pH of the skin remained more or less constant throughout the study period, ranging between 8 and 9 in skin treated with TSP, depending on the concentration, while it was two units lower in the control samples.
Some physical and thermal characteristics of amaranth starch Algunas propiedades físicas y térmicas del almidón de amaranto
Authors: Calzetta Resio A.N. , Tolaba M.P. , Suarez C.
Published: March 2007

Starch was isolated from Amaranthus cruentus to study some physicochemical properties (swelling power, solubility, water absorption and sorption equilibria) and compared with corn starch. Swelling power and water absorption capacity were higher for amaranth than for corn starch, whereas the solubility of amaranth starch was, in comparison, lower. The adsorption capacity at monolayer value of both starches was practically coincident. However, the sorbed water at monolayer seemed to be more firmly adsorbed in corn than in amaranth starch. The specific surface area of adsorption for both materials was above 300 m2/g. Gelatinization temperatures of amaranth starch measured by differential scanning calorimetry varied with the water/starch ratio and the heating rate. For water/ starch ratios higher than 2:1, the peak temperature was practically constant and equal to 68.3 °C. The enthalpy of gelatinization reached a maximum of 11.5-11.7 J/g. Two activation energies were found with a distinct break point at 69.2 °C, where rapid gelatinization of amaranth starch begins.
Incidence of toxigenic molds in farm-level cheesemaking units from Arzua (La Coruña, Spain)
Authors: VÁZquez-Belda B. , Fente-Sampayo C.A. , Quinto-Fernandez E. , Franco-Abuin C. , RodrîGuez-Otero J.L. , Cepeda-Saez A.
Published: March 2007

Four hundred ten strains of Penicillium and 120 strains of Aspergillus isolated from air, surfaces, and cheese, in 10 farm-level cheesemaking farm units from Arzúa (La Coruña, Spain) were classified. The mycotoxin production using the APA medium and thin-layer chromatography was proved. With respect to the production of aflatoxins, 19% from Aspergillus strains resulted positive in agar APA and 18.3% by thin-layer chromatography. With regard to citrinin, 22.2% from Penicillium strains and 5% from the Aspergillus strains were producers of this mycotoxin; 16.1% from Penicillium and 1.67% from Aspergillus produced ochratoxin A. With regard to patulin, 5.4% from the fungi belonging to the genus Penicillium studied were producers of this mycotoxin as well as 3.3% from the Aspergillus. Just 6.6% from the Aspergillus strains resulted in the production of sterigmatocystin.
Nota: Influencia de los sólidos solubles, de la acidez y del azúcar sobre el color del dulce de leche/ Note: Influence of soluble solids, acidity and sugar on the color of dulce de leche
Authors: Pauletti M.S. , Castelao E.L. , Bernardi M.C.
Published: March 2007

An exploratory study at pilot scale using response surface methodology was conducted to assess the influence of soluble solids concentration, initial acidity of the mixture and initial sucrose concentration on the color of dulce de leche. Variance and factor analysis were performed, and response surfaces were obtained. Results showed that the studied variables explain 90% of the variability of lightness (L*). Initial mixture acidity, soluble solids concentration and sucrose concentration affected significantly dulce de leche lightness; the lower the initial acidity and the higher the sucrose and soluble solids concentration, the darker the color (lower L* value) observed.
Determinación de saponinas en las principales leguminosas cultivadas en España/Determination of saponins in the main legumes cultivated in Spain
Authors: Ayet G. , Muzquiz M. , Burbano C. , Robredo L.M. , Cuadrado C. , Price K.R.
Published: March 2007

The seeds of different legumes ( Lupinus albus var. Multolupa, Lens culinaris var. Magda 20, Cicer arietinum type Kabuli, Phaseolus vulgaris var. Guerniquesa, Vicia faba var. Alameda) were analysed for soyasaponin content and soyasapogenol composition using different chromatographic techniques. The soyasapogenol was present in all species, except in L. albus; the content ranged from 0.02 mg/g in V. faba var. Alameda to 1.21 mg/g in P. vulgaris var. Guerniquesa. Two soyasaponins were detected by FAB-MS. Soyasaponin I was detected in the L. culinaris, C. arietinum, V. faba and P. vulgaris extracts and soyasaponin V in the P. vulgaris extracts.
Influence of wheat flour and Lactobacillus strains on the dynamics of by-products from amylolytic activities / Influencia de la harina de trigo y de la especie de Lactobacilo en la dinámicade subproductos de la actividad amilolítica
Authors: Martinez-Anaya M.A. , Rouzaud O.
Published: March 2007

Amylolytic activity of six flours from three European wheat cultivars (Obelisk, Camp Remy and Fresco, at 70 and 100% extraction level), and five lactobacilli strains (Lactobacillus plantaracm B-39, L-73; L. brevis 25a, L-62, and L. sanfrancisco L-99), as well as the dynamics of by-products from amylolytic degrading action in mixed flour-lactobacilli systems have been investigated. α-Amylase activity of flours depended on ash content; whole flours from the three cultivars had similar values, which were of the order of three to ten times that of white flours. L. sanfrancisco showed the lowest α-amylase activity, and L.plantarum the highest. At the concentrations of lactobacilli used in sourdough processes, flour was the main contributor to final α-amylase action in flour-lactobacilli mixtures. Production of monosaccharides followed variable trends, depending on the extraction level of the flour and on the Lactobacillus strain. The dynamics of monosaccha rides, due to their active and variable involvement in metabolic pathways, could not be adjusted to model regression equations. Maltose levels increased during fermentation, although an effec tive incorporation in Lactobacillus metabolism was observed. A second order polynomy could be used to describe changes in maltose. Low molecular weight dextrins (LMWD) with degrees of polymerization (DP) from three to seven, only appeared and accumulated during the late stages of fermentation. LMWD with a DP of three was the only oligosaccharide capable of being incor porated by lactobacilli, and, of the strains tested, only by L. brevis (25a). The larger dextrins seemed to be involved in further degrading enzymic reactions yielding smaller size fragments. Dynamics of LMWD followed exponential curves, with highly significant regression coefficients.
Microstructure of wheat flour tortillas: effects of soluble and insoluble fibres / Microestructura de tortillas de harina de trigo: éfectos de la adición de fibra soluble e insoluble
Authors: Seetharaman K. , McDonough C.M. , Waniska R.D. , Rooney L.W.
Published: March 2007

Soluble and insoluble fibres influenced both the quality and microstructure of dough and wheat flour tortillas. Doughs containing 8% soluble fibre had poor gluten development and extensive starch gelatinization during baking. This resulted in a tortilla with a dense, pasty crumb. Doughs containing 8% insoluble fibre had better gluten structures than those prepared using soluble fibres. Strands of insoluble fibre particles, however, physically disrupted the gluten network, causing the air bubbles to collapse, and decreased the shelf-stability of tortillas. It appears that soluble and insoluble fibres weaken the gluten matrix by different mechanisms.
Influence of enzymes, pH and temperature on the kinetics of whey protein hydrolysis / Influencia de los enzimas, pH y temperatura en la cinética de la hidrólisis de las proteínas del lactosuero
Authors: Camacho F. , González-Tello P. , Guadix E.M.
Published: March 2007

The influence of pH, temperature and the mixture of enzymes (MKC Protease 660 L and PEM 2500 S) on the enzymatic hydrolysis of whey proteins was studied. The experiments show that all results were reproducible via a kinetic model that supposes the rapid and irreversible binding of part of the proteases to an inhibitor in the substrate, followed by a zero-order hydrolysis with respect to the substrate which occurs simultaneously with a second order enzymatic denatural ization produced by an attack of the free proteases upon those bound to the substrate-enzyme complex. Use of the optimum operating temperature of 60 °C and pH 8-10 led to a greater degree of hydrolysis. However, increasing the pH to these levels means that the salt content, on neutral izing the hydrolysate, is somewhat high and this is often unsuitable for the preparation of special diets. In the experiments performed with mixtures of enzymes, two contrasting phenomena occurred; there appears to be synergism between the proteases, which is preceded by a loss in enzymatic activity greater than that which can be accounted for by the presence of the inhibitor in the whey proteins.
The effect of panel selection and training on external preference mapping using a low number of samples / Efecto de la selección y entrenamiento de los catadores sobre la cartografía externa de preferencias, utilizando un número reducido de muestras
Authors: Gou P. , Guerrero L. , Romero A.
Published: March 2007

External preference mapping (PREFMAP) relates the preference data of a group of consumers to a multi-dimensional representation of the stimuli. This representation can be obtained from descriptive sensory data generated by a panel. Four vegetable oil samples were analysed. Three different stimulus spaces were obtained from generalized Procrustes analysis (GPA) of descrip tive sensory data generated by three panels (12 assessors): a non-selected panel, a selected panel and the latter after training. The preference data of each consumer was regressed against the product co-ordinates obtained from each stimulus space using the vector model. The interpreta tion of stimulus space was easier with selected assessors, but in an overall sense the three stim ulus spaces were similar. However, the slight differences between the different sensory spaces produced important differences in the PREFMAP interpretation.
Revision: Extracción con CO2 a alta presión. Fundamentos y aplicaciones en la industria de alimentos / Review: High pressure CO2 extraction. Fundamentals and applications in the food industry
Authors: del Valle J.M. , Aguilera J.M.
Published: March 2007

Supercritical extraction (SFE) is a unit operation that exploits the dissolving power of supercritical fluids (SF) under conditions above their critical temperature and pressure. It is possible to obtain solvent-free extracts using SF and the extraction is faster than using conventional organic solvents. These advantages are due to the high volatility of SF (gases under normal environmental conditions) and improved transport properties (i.e., high diffusivity and low viscosity). When using carbon diox ide (CO,) in particular, moderate-temperature processing and high selectivity towards valuable microconstituents in natural products can be achieved. This article presents a review of transport properties and solubilities in SF, particularly CO2, as well as other underlying factors that are respon sible for the kinetics and phase equilibrium in SFE processes. It also describes the selective CO 2 ex traction of essential oils, pungent principles, carotenoid pigments, antioxidants, antimicrobials, and related substances to be used as ingredients for the food, drug and perfume industries, from spices, herbs and other plant materials. These very important applications are discussed from the point of view of the potential applications of SFE in Latin America. The two most important commercial ap plications of SFE in the food industry, namely hop extraction and coffee decaffeination, are reviewed to a limited extent. Some other potential applications briefly described include extraction and frac tionation of edible fats and oils, purification of solid matrices, and concentration of fermentation broths, fruit juices and other extracts. In most cases CO2 extracts are compared with counterparts obtained using conventional methods.
Chemical and functional properties of sardine (Sardina pilchardus W.) dark and light muscle proteins during frozen storage. Effect of washing on mince quality / Propiedades químicas y funcionales de las proteínas del músculo oscuro y claro de sardina (Sardina pilchardus w.) durante el almacenamiento en congelación. Efecto del lavado en la calidad del músculo picado
Authors: Montero P. , Pardo M.V. , Gómez-Guillén M.C. , Borderias J.
Published: March 2007

This paper examines the effects of eight months of frozen storage on the protein conformation and functionality of whole, light and dark sardine muscles, and washed mince. The variation in protein surface hydrophobicity and Ca-ATPase activity was different in dark muscle from that in whole muscle over the storage period. The dark muscle lacked gel forming capacity because of its higher fat content and a greater presence of low molecular weight proteins, and it also became insoluble faster than the light muscle. The Ca-ATPase activity of the actomyosin extracted from the dark muscle was higher than in light or whole muscle during the first three months. Washing the minced muscle induced conformational changes in the myosin molecule which, together with the added cryoprotectants, contributed to greater functional stability of the washed mince at least during the first three month's storage, at which stage gels were somewhat softer and more elastic than with unwashed mince.
Note. Sensory analysis during ripening of Fynbo cheese salted with NaCl / KCl brine / Nota. Evaluación sensorial durante la maduracion de queso Fynbo salado con una disolución de NaCl / KCl
Authors: Zorrilla S.E. , Rubiolo A.C.
Published: March 2007

Fynbo cheeses salted with NaCl and with NaCl/KCl brine were evaluated for sensory characteristics over one month of ripening period. Samples were tested by a trained five-member panel. Semi-struc tured quantitative descriptive analysis scales were used to evaluate saltiness, bitterness, firmness and final quality. Typical values of saltiness and firmness were observed at 29 ripening days in the cheeses studied ( p < 0.05). Although slight bitterness was detected in cheeses salted with KCl/NaCl brine, both types of cheese were considered acceptable for commercialization ( p < 0.05).
Effects of preheating temperature, moisture, and sodium metabisulfite content on quality of noodles prepared from maize flour or meal / Efecto de la temperatura de precalentamiento, humedad y contenido de metabisulfito de sodio en la calidad de fideos de harina o de sémola de maíz
Authors: Waniska R.D. , Yi T. , Lu J. , Xue-Ping L. , Xu W. , Lin H.
Published: March 2007

Preheating temperature, maize flour particle size, and levels of water and sulfite were tested during preparation of maize noodles. Heating a mixture of maize flour and water (43-45 % moisture) at 90-95 °C was required to extrude maize noodles using a pasta maker. Maize flour with smaller par ticle size yielded better noodles than did maize meal. Addition of sulfite enabled production of noodles at lower processing temperatures, however, cooking losses increased. Addition of more water yielded noodles that required longer cooking time, but decreased cooking losses. Functionalities of starch and protein in raw ingredients and in products were determined. Starch gelatinized and retrograded during processing of maize extrudates, as indicated by changes in pasting viscosity curves. Above 40 °C, maize proteins increased mixing viscosity of dough. Increased integrity of cooked maize noodles, however, corresponded to increased amounts of gelatinized and retrograded starch.
Partial protease activity characterization of squid (Todaropsis eblanae) mantle / Caracterización parcial de la actividad proteolítica del manto de pota (Todaropsis eblanae)
Authors: Ayensa M.G. , An H. , Gómez-Guillén M.C. , Montero P. , Borderías A.J.
Published: March 2007

Proteolytic activity in mantle of Todaropsis eblanae was maximum at 40 and 65 °C. Several peaks of activity were detected over the pH range studied (1.5-9.5), indicating the presence of acidic, neutral and alkaline proteases, depending on the temperature. The substantial enzymic inhibition at acidic pH by the inhibitor trans-epoxysuccinyl-L-leucylamine-4-guanidine butane (E-64) revealed the pre dominance of lysosomal cysteine proteases (cathepsins) which showed higher activity at 65 °C than at 40 °C. At 65 °C and pH 5.5 metallo-proteases were also detected by the inhibition with phenanthroline. Serine protease activity predominated at neutral pH (higher at 40 °C than at 65 °C), and cysteine proteases were detected at alkaline pH. There was evidence of cathepsin B and L activity at 65 °C and to a lesser degree at 40 °C.
Consequences of frozen storage for nutritional value of hake / Consecuencias del almacenamiento en congelación en el valor nutricional de merluza
Authors: Alvarez C. , Huidobro A. , Tejada M. , Vázquez I. , De Miguel E. , Gómez de Segura I.A.
Published: March 2007

Differences between fresh and frozen hake muscle in which proteins were highly aggregated during frozen storage, and their relationship with nutritional quality are evaluated. The differences between fresh and frozen muscle proteins were studied on the basis of protein solubility, type and state of muscle aggregation and amino acid composition. Nutritional value was determined by nitrogen bal ance and amino acid composition in the blood. The high level of aggregation in the frozen muscle was due mainly to disulfide and other covalent bonds. Lysine diminished in frozen muscle and in plasma. Although in frozen fish muscle, proteins were highly aggregated even by disulfide and non- disulfide covalent bonds, nitrogen balance in fresh and frozen fish was similar.
Private Duty Service Expansion through Accreditation and Marketing Excellence
Authors: Gingerich Barbara Stover
Published: March 2007

Private duty services take on new dimensions with the PPS home care reimbursement system and the Balanced Budget Act of 1997. Families seeking to keep loved ones at home are reaching out and searching for quality private care alternatives. Home health is poised to meet these increasing needs. Accreditation and marketing are two important ingredients in the success of private duty home care services.
Accreditation Commission for Home Care
Authors: Cesar Tom , Gingerich Barbara Stover
Published: March 2007

The Accreditation Commission for Home Care (ACHC) was established in 1986 and predominately focused on accreditation of home care organizations within the state of North Carolina. This span of focus was expanded in 1996. During the intervening years, increased approval and interest in ACHC's standards and survey process has occurred. This article provides an overview of the commission and its standards.
Measuring Costs and Quality of TeleHomecare
Authors: Britton Bonnie Perry , Engelke Martha Keehner , Rains Dan B. , Mahmud Kahlid
Published: March 2007

Home care agencies must explore alternative methods of care delivery if they are to remain competitive in the health care market of the future. The use of TeleHomecare can help agencies maintain a high level of quality while reducing costs. Since this is a relatively new modality of care delivery, there is a need to monitor and document outcomes. Physicians, managed care companies, and public policy makers will require reliable and valid data before they can become advocates of TeleHomecare. This article describes how one TeleHomecare program has developed an outcome-oriented database and how these data are used in marketing the program.
Teaching Patients to Manage Diabetes Safely in the Home
Authors: Hanstine Sandra , Fanning Virginia
Published: March 2007

Using an interdisciplinary process improvement team approach the average patient's diabetic knowledge improved 27% during the episode of care. This improvement was accomplished by creating a pre-/post- test that could also be used as a teaching tool.
Data Mining Techniques for Patient Satisfaction Data in Home Care Settings
Authors: Mylod Deirdre E. , Kaldenberg Dennis O.
Published: March 2007

The purpose of this article is to describe tools (top box analysis, bottom box analysis, and segmentation analysis) that allow more thorough use and interpretation of patient satisfaction data. Techniques are demonstrated using data gathered from 22,937 home care patients at 174 agencies during the first quarter of 1999. Results provide unique insights into home care performance. Top box analysis revealed that nursing issues are most likely to be given the highest ratings. Bottom box analysis showed that very low ratings were most prevalent in explanations of billing and cost, resolution of problems, and involvement in decision making. Simple segmentation analysis showed significant differences in satisfaction based on patient characteristics. Complex segmentation analysis identified the most and least satisfied groups of patients using combinations of patient characteristics.
The home health care delivery crisis for patients with chronic respiratory disease: Effect of DRGs
Authors: Hayes Mary B. , McDonald Maryanne
Published: March 2007

The authors address several issues in the dilemma of providing skilled home health services to the chronically ill pulmonary patient. The restrictions of current reimburse ment plus the fear of future methods make the professional a patient advocate who needs to be creative in establishing care plans and assertive in negotiating reimbursement with the insurance carriers. The authors provide excellent suggestions in several areas, such as care plan development and establishing appropriate visiting patterns. Two case studies are given to demonstrate effective case management.
Pharmacotherapy for chronic obstructive pulmonary disease
Authors: McPherson Mary Lynn
Published: March 2007

This article reviews the four basic drug categories used to manage chronic obstructive pulmonary disease. If the home health care professional becomes familiar with the mechanisms of action, dosing considerations, and patient education issues associated with these drug categories, management of the home care patient with chronic obstructive pulmonary disease is enhanced.
Hospice volunteer programs: Foundational beliefs behind recruitment, training, and retention
Authors: Flickinger Judith T.
Published: March 2007

One of the major components of hospice is a reliable, well managed volunteer program. This article provides information to assist professional staff as well as administrators toward retention, recruitment, and training. The author also offers effective, practical suggestions on utilization and how to provide an environment for the volunteer to be able to function with the goal of enhancing the quality of life.