Two-channel decentralized integral action controller design

Cataloged from PDF version of article.We propose a systematic controller design method that provides integral-action in linear time-invariant two-channel decentralized control systems. Each channel of the plant is single-input–single-output, with any number of poles at the origin but no other poles in the instability region. An explicit parametrization of all decentralized stabilizing controllers incorporating the integral-action requirement is provided for this special case of plants. The main result is a design methodology that constructs simple low-order controllers in the cascaded form of proportional-integral and first-order blocks

PID stabilization of MIMO plants

Cataloged from PDF version of article.Closed-loop stabilization using proportional–integral–derivative (PID) controllers is investigated for linear multiple-input–multiple-output (MIMO) plants. General necessary conditions for existence of PID-controllers are derived. Several plant classes that admit PID-controllers are explicitly described. Plants with only one or two unstable zeros at or “close” to the origin (alternatively, at or close to infinity) as well as plants with only one or two unstable poles which are at or close to origin are among these classes. Systematic PID-controller synthesis procedures are developed for these classes of plants

Lean leadership behaviors in healthcare organizations:A systematic literature review

This systematic literature review compares contextual similarities and differences of leader behaviours across various hierarchical levels and lean maturity levels. Since healthcare organisations are generally unique, the successful implementation of Lean Healthcare likely demands typical supportive leader behaviours at all hierarchical levels. However, the 107 reviewed articles indicate that most of the healthcare leader behaviours are similar to those of manufacturing leaders, but more relations-oriented in the early lean stages, rather than task-oriented. As most healthcare studies examined leaders at the operational and tactical levels, future multi-level research should also study strategical managers and the longitudinal effects of their behaviours

Strong Stabilization of a Class of MIMO Systems

Cataloged from PDF version of article.Stabilization of finite dimensional linear, time-invariant, multi-input multi-output plants by stable feedback controllers, known as the strong stabilization problem, is considered for a class of plants with restrictions on the zeros in the right-half complex plane. The plant class under consideration has no restrictions on the poles, or on the zeros in the open left-half complex plane, or on the zeros at the origin or at infinity; but only one finite positive real zero is allowed. A systematic strongly stabilizing controller design procedure is proposed. The freedom available in the design parameters may be used for additional performance objectives although the only goal here is strong stabilization. In the special case of single-input single-output plants within the class considered, the proposed stable controllers have order one less than the order of the plant

Comparison in a rat thigh abscess model of imipenem, meropenem and cefoperazone-sulbactam against Acinetobacter baumannii strains in terms of bactericidal efficacy and resistance selection

BACKGROUND: We compared imipenem, meropenem and cefoperazone-sulbactam against hospital originated A. baumannii strains in terms of bactericidal efficacy and selection of resistant mutants during treatment in a rat thigh abscess model. METHODS: A total of 18 strains were inoculated in 54 animals (one strain for three animals). Randomly selected 10 among these 18 strains were inoculated in another 10 rats as the control group. Imipenem, meropenem and cefoperazone-sulbactam were the antibiotics compared. After four days of treatment, Wistar albino rats (200 to 250 g) were sacrificed and the abscess materials were processed for mean colony counts and for the presence of resistant mutants. RESULTS: The mean CFUs per gram (mean ± (std. deviation) [×10(4)]) of the abscess were: 9,14 (25,24), 2,11 (3,78), 1,20 (1,70) in the imipenem (n = 17), meropenem (n = 18) and cefoperazone-sulbactam (n = 17) groups, respectively. The differences were not significant. On the other hand, no resistant mutant was detected in abscess materials. CONCLUSION: This study indicated; first, cefoperazone-sulbactam is comparable to carbapenems in bactericidal efficacy in this particular abscess model and second, emergence of resistance due to spontaneous mutations is not at least a frequent phenomenon among A. baumannii

Avaliação motora para prevenção de deficiências do bebê pré-termo e em risco de atraso no desenvolvimento / Motor evaluation for preventing disabilities on preterm babies and babies at risk of developmental delays

Introdução: O bebê de risco é considerado como aquela criança que está exposta a fatores biológicos e/ou ambientais que interferem com o desenvolvimento infantil típico e impactam a aquisição das habilidades esperados para a faixa etária dos primeiros anos de vida. Objetivo: Avaliar o desenvolvimento motor de bebês pré-termo e a termo com risco de atraso no desenvolvimento atendidos em um ambulatório de pediatria. Métodos: Trata-se de um estudo descritivo de campo, com abordagem observacional. Foram avaliados 17 lactentes de quatro, seis e oito meses de idade, com risco de atraso no desenvolvimento por meio do consentimento dos pais. Os instrumentos para coleta de dados foram um roteiro elaborado pelas pesquisadoras com perguntas relacionadas à história passada e atual dos bebês e seus pais, e a Alberta Infant Motor Scale (AIMS) para avaliação do desenvolvimento motor. Resultados: Verificou-se que dois bebês apresentaram atraso no desenvolvimento motor, três eram suspeitos de atraso e doze tiveram desenvolvimento motor normal para a idade atual. Constatou-se que os bebês que estavam em intervenção terapêutica ocupacional precoce apresentaram desenvolvimento típico em comparação aos bebês que foram assistidos apenas no serviço de rotina pediátrica. Conclusão: Destaca-se a importância da estimulação precoce nos primeiros meses de vida para prematuros e de crianças com risco de atraso no desenvolvimento, uma vez que todos as crianças que estavam no programa de estimulação precoce e recebendo as intervenções de terapia ocupacional, apresentaram desenvolvimento motor adequado para a idade. AbstractIntroduction: The baby at risk is considered as that child who is exposed to biological and/or environmental factors that interfere with the typical child development and impact the acquisition of the skills expected for the age group of the first years of life. Objective: to evaluate developmental delays in premature infants and terms of risk of developmental delay seen in a pediatric outpatient clinic. Methods: This is a descriptive field study, with an observational approach. 17 infants of four, six and eight months of age were taxed, with risk of developmental delay through parental consent. The instruments for data collection were developed by researchers with questions related to the recent and current history of their parents and parents, and an AIMS (Alberta Infant Motor Scale) to assess the development of these engines. Results: It was found that two patients had delayed motor development, three were suspected of delayed development and had normal motor development for their current age. It was found that babies who were undergoing occupational therapeutic intervention started the typical development compared to babies who were seen only in the pediatric routine service. Conclusion: The importance of early stimulation in the first months of life for premature children and those at risk of developmental delay is highlighted, since all children as children who have had no early stimulation program and receive occupational therapy assessments, age-appropriate motor development.Keywords: Child Development; Early Intervention; Occupational Therapy. ResumenIntroducción: El bebé en riesgo se considera aquel niño que está expuesto a factores biológicos y / o ambientales que interfieren con el desarrollo típico del niño e impactan la adquisición de las habilidades esperadas para el grupo de edad de los primeros años de vida. Objetivo: Evaluar posibles retrasos motores en recién nacidos prematuros y a término con riesgo de retraso en el desarrollo atendidos en una clínica ambulatoria pediátrica. Métodos: Este es un estudio de campo con un enfoque observacional y descriptivo. Diecisiete bebés de cuatro, seis y ocho meses fueron evaluados, con riesgo de retraso en el desarrollo a través del consentimiento de los padres. Los instrumentos para la recolección de datos fuero unnguión desarrollado por los investigadores con preguntas relacionadas con la historia pasada y actual de los bebés y sus padres, y la Escala motora infantil de Alberta (AIMS) para evaluar el desarrollo motor. Resultados: Se descubrió que dos bebés tenían retraso en el desarrollo motor, treseransospechosos de retraso y doce tenía nun desarrollo motor normal para la edad actual. Se descubrió que los bebés que se sometían a una intervención terapéutica ocupacional temprana mostraronun desarrollo típico en comparación con los bebés que solo fueron atendidos en el servicio de rutina pediátrico. Conclusión: Se destaca la importancia de la estimulación tempranaen los primeros meses de vida para bebés prematuros y niños en riesgo de retraso del desarrollo, ya que todos los niños que esta banenel programa de estimulación temprana y que recibieron intervenciones de terapia ocupacional mostraron desarrollo motor apropiado para la edad.Palabras clave: Desarrollo infantil, estimulación temprana, terapia ocupacional.  

On the size of PLA's required to realize binary and multiple-valued functions

This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. As such, it is in the public domain, and under the provisions of Title 17, United States Code, Section 105, may not be copyrighted.IEEE Transactions on Computers, C-38, Jan. 1989, pp. 82-98, 1988While the use of programmable logic arrays in modern logic design is common, little is known about what PLA size provides reasonable coverage in typical applications. We address this question by showing upper and lower bounds on the average number of product terms required in the minimal realization of binary and multiple-valued functions as a function of the number of nonzero output values. When the number of such values is small, the bounds are nearly the same, and accurate values for the average are obtained. In addition, an upper bound is derived for the variance of the distribution of the number of product terms required in minimal realizations of binary functions. When the number of nonzero values is small, we find that the variance is small, and it follows that most functions require nearly the average number of product terms. The variance, in addition to the upper and lower bounds, allow conclusions to be made about how PLA size determines the set of realizable functions. Although the bounds are most accurate when there are few nonzero values, they are adequate for analyzing commercially available PLA’s, which we do in this paper. Most such PLA’s are small enough that our results can be applied. For example, when the number of nonzero values exceeds some threshold uT, determined by the PLA size, only a small fraction of the functions can be realized. Our analysis shows that for all but one commercially available PLA, the number of nonzero values is a statistically meaningful criteria for determining whether or not a given function is likely to be realized

The Relationship between Gram-Negative Colonisation and Bloodstream Infections in Neonates: A Systematic Review and Meta-Analysis.

OBJECTIVES: Neonates admitted to Neonatal Intensive Care Units (NICU) are at significant risk of developing bloodstream infections (BSIs). Gram-negative bacteria (GNB) both colonise and infect, but the association between these entities is unclear. By conducting a systematic literature review, we aimed to explore the impact of factors on the association between GN colonisation and GN-BSI at both baby level and unit level. METHODS: We searched Medline, Embase, and Cochrane Library. Observational cohort studies published after 2000 up to June 2016 reporting data on the total number of neonates (0-28 days) colonised with GNB assessed by rectal/skin swab culture and the total number of neonates with GN-BSI (same bacteria) were included. Studies were excluded if data on skin/rectal colonisation, neonates, and GNB could not been identified separately. The meta-analyses along with multivariate meta-regression with random-effect model were performed to investigate factors associated with the GN colonisation and GN-BSI at baby-level and unit-level. RESULTS: 27 studies fulfilled our inclusion criteria, 15 for the baby-level and 12 for the unit-level analysis. Study heterogeneity was high, with suboptimal overall quality of reporting assessed by the STROBE-NI statement (44.8% of items adequately reported). In 1,984 colonised neonates, 157 (7.9%) developed GN-BSI compared with 85 of 3,583 (2.4%) non-colonised neonates. Considerable heterogeneity across studies was observed. Four factors were included in the meta-regression model: Gross domestic product (GDP), pathogen, outbreak, and frequency of screening. There was no statistically significant impact of these factors on GN colonisation and GN-BSI in baby level. We were unable to perform the multivariate meta-regression due to the insufficient reported data for unit level. CONCLUSIONS: Study limitations include the small number and the high heterogeneity of the included studies. While this report shows a correlation between colonisation and BSI risk, this data currently doesn't support routinely screening for GNB. The analysis of large cohorts of colonised neonates with clinical outcomes is still needed to define the major determinants leading from colonisation to infection

Prospective evaluation of chronic pain associated with posterior autologous iliac crest bone graft harvest and its effect on postoperative outcome

<p>Abstract</p> <p>Background</p> <p>Autogenous Iliac Crest Bone Graft (ICBG) has been the "gold standard" for spinal fusion. However, bone graft harvest may lead to complications, such as chronic pain, numbness, and poor cosmesis. The long-term impact of these complications on patient function and well-being has not been established but is critical in determining the value of expensive bone graft substitutes such as recombinant bone morphogenic protein. We thus aimed to investigate the long-term complications of ICBG. Our second aim was to evaluate the psychometric properties of a new measure of ICBG morbidity that would be useful for appropriately gauging spinal surgery outcomes.</p> <p>Methods</p> <p>Prospective study of patients undergoing spinal fusion surgery with autologous ICBG. The SF-36v2, Oswestry Disability Index, and a new 14-item follow-up questionnaire addressing persistent pain, functional limitation, and cosmesis were administered with an 83% response rate. Multiple regression analyses examined the independent effect of ICBG complications on physical and mental health and disability.</p> <p>Results</p> <p>The study population included 170 patients with a mean age of 51.1 years (SD = 12.2) and balanced gender (48% male). Lumbar fusion patients predominated (lumbar = 148; cervical n = 22). At 3.5 years mean follow-up, 5% of patients reported being bothered by harvest site scar appearance, 24% reported harvest site numbness, and 13% reported the numbness as bothersome. Harvest site pain resulted in difficulty with household chores (19%), recreational activity (18%), walking (16%), sexual activity (16%), work activity (10%), and irritation from clothing (9%). Multivariate regression analyses revealed that persistent ICBG complications 3.5 years post-surgery were associated with significantly worse disability and showed a trend association with worse physical health, after adjusting for age, workers' compensation status, surgical site pain, and arm or leg pain. There was no association between ICBG complications and mental health in the multivariate model.</p> <p>Conclusion</p> <p>Chronic ICBG harvest site pain and discomfort is reported by a significant percentage of patients undergoing this procedure more than three years following surgery, and these complications are associated with worse patient-reported disability. Future studies should consider employing a control group that does not include autologous bone graft harvest, e.g., a group utilizing rhBMP, to determine whether eliminating harvest-site morbidity does indeed lead to observable improvement in clinical outcome sufficient to justify the increased cost of bone graft substitutes.</p

PID Controller Synthesis for a Class of Unstable MIMO Plants with I/O Delays

Cataloged from PDF version of article.Conditions are presented for closed-loop stabilizability of linear time-invariant (LTI) multi-input, multi-output (MIMO) plants with I/O delays (time delays in the input and/or output channels) using PID (Proportional + Integral + Derivative) controllers. We show that systems with at most two unstable poles can be stabilized by PID controllers provided a small gain condition is satisfied. For systems with only one unstable pole, this condition is equivalent to having sufficiently small delay-unstable pole product. Our method of synthesis of such controllers identify some free parameters that can be used to satisfy further design criteria than stability. (C) 2006 Elsevier Ltd. All rights reserve