bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermo-kinetic computer simulation of differential scanning calorimetry curves of AlMgSi alloys
Authors: Falahati A. , Povoden-Karadeniz E. , Lang P. , Warczok P. , Kozeschnik E. 
Published: September 2010

Abstract
The microstructure evolution in heat-treatable Al-alloys is characterized by a complex sequence of precipitation processes. These can be either endothermic or exothermic in nature and they can be investigated by thermal analysis. The individual peaks identified in a differential scanning calorimetry (DSC) analysis can be correlated to the nucleation, growth and dissolution of certain types of precipitates. Simultaneously, these data can also be obtained by thermo-kinetic simulation based on models implemented, for instance, in the software MatCalc. The simulations make use of information stored in thermodynamic databases, including stable and metastable phases. In the present work, a thermo-kinetic computational analysis of Al–Mg–Si DSC curves is carried out. The comparison with experimentally observed DSC signals for precipitation and dissolution of metastable GP-zones, β″, β′, as well as stable β-Mg2Si and Si precipitates provides a quantitative insight into the kinetics and sequence of precipitation during DSC probing. The combination of thermo-kinetic and experimental DSC analysis offers new possibilities in interpretation of DSC peaks with multiple metastable phases. In the present paper, we discuss the linking of the simulated precipitation sequence with the measured DSC signal. In addition, with the proposed methodology, a consistent set of parameters to describe the non-equilibrium kinetic parameters of a specific alloy system can be obtained, which can substantially aid in alloy and process development.
A 32-year-old Woman with Major Depressive Disorder, Pathological Skin Picking, and Trichotillomania
Authors: Asemota Babatunde 
Published: September 2010

CME Educational Objectives

1.
Review the dysfunction of glutamate neurotransmission in some psychiatric disorders.

2.
Discuss the neurobiology of pathological skin picking and trichotillomania.

3.
Discuss the potential use of memantine augmentation in patients with pathological skin picking and trichotillomania.
Risk Factors for and Results of Late or Delayed Amputation Following Combat-Related Extremity Injuries
Authors: Helgeson Melvin D. , Potter Benjamin K. , Burns Travis C. , Hayda Roman A. , Gajewski Donald A. 
Published: September 2010

We studied patients with combat-related injuries that required delayed amputation at least 4 months after the initial injury due to dysfunction, persistent pain, and patient desires. Late amputations were performed 22 times in 22 patients (21 men, 1 woman) since 2003. Fourteen patients underwent transtibial amputation, 5 transfemoral amputations, 1 knee disarticulation, and 2 transradial amputations. The primary indications for late amputation were neurologic dysfunction in 6 patients, persistent or recurrent infection in 6, neurogenic pain in 3, non-neurogenic pain in 5, and a globally poor functional result in 2. Sixteen of 22 patients reported multiple indications for electing to undergo amputation, with an average of 2.1 specific indications per patient. At final clinical follow-up an average of 13 months after amputation, all patients reported subjectively improved function and reported that they would undergo amputation again under similar circumstances.
When medically and functionally practicable, every effort is given to limb salvage following severe combat-related extremity injuries. There is no single risk factor that increases the likelihood of delayed amputation, but the combination of complex pain symptoms with neurologic dysfunction appears to increase the risk, particularly if the initial insult is a severe hindfoot injury or distal tibia fracture. With appropriately selected and counseled patients, elective late amputation results in a high degree of patient satisfaction and subjectively improved function.
Unicompartmental and Total Knee Arthroplasty in the Over 70 Population
Authors: Fisher David A. , Dalury David F. , Adams Mary Jo , Shipps Melanie R. , Davis Kenneth 
Published: September 2010

This retrospective study compares the short-term outcomes of small-incision unicompartmental knee arthroplasty (41 patients) with standard total knee arthroplasty (TKA) (50 patients) in 91 consecutive patients older than 70 years. Knee Society Scores and range of motion (ROM) were assessed preoperatively, at 6 weeks and 6 months, and through a minimum of 2 years. Postoperative comparisons included blood loss, transfusions, narcotic consumption, length of hospital stay, and complications.
While Knee Scores and ROM were similar preoperatively, both were better in the unicompartmental group at each postoperative time interval. Patients with unicompartmental replacements had a much quicker return of function and discontinuation of pain medication. Blood loss was significantly more for the TKA group, as was the need for blood transfusion. None of the unicompartmental patients required transfusion. Narcotic use and length of hospital stay were also significantly less for the unicompartmental group. The overall rate of postoperative medical and surgical complications was similar for the 2 groups, with 1 major complication in each. Overall, the physiologic impact of unicompartmental knee arthroplasty was much less than TKA in this older patient population and resulted in a faster recovery.
Effectiveness of External Rotation Immobilization in Highly Active Young Men with Traumatic Primary Anterior Shoulder Dislocation or Subluxation
Authors: Tanaka Yoshitaka , Okamura Kenji , Imai Tomohito 
Published: September 2010

We treated 15 highly active young men (16 shoulders) with traumatic primary anterior shoulder dislocation or subluxation using 3-week external rotation immobilization. Fourteen patients (14 shoulders) were members of the Self-Defense Force and the other patient (2 shoulders) was a high school student who played club-level rugby. Average patient age at the time of the primary injury was 21.3 years (range, 17–26 years). Magnetic resonance imaging (MRI) was performed on 14 of 16 shoulders after the 3-week external rotation immobilization and showed that the anteroinferior labrum was reduced on the glenoid rim in 11 shoulders but remained medially displaced on the glenoid neck in 3 shoulders. Five shoulders, including these 3 shoulders, underwent arthroscopic Bankart repair after 3-week external rotation immobilization. Eleven shoulders continued nonoperative treatment after the immobilization. Four of 11 shoulders had no recurrence of symptoms for >2 years, and these patients were able to return to their preinjury activities. However, 7 shoulders experienced recurrence within 2 years.
We concluded that external rotation immobilization may not be as effective as mentioned previously in highly active young men with primary traumatic anterior shoulder dislocation or subluxation. Whether a patient has instability symptom recurrence after external rotation immobilization depends on more than the fact that the anteroinferior labrum is not reduced on MRI.
Wound Healing in Total Joint Arthroplasty
Authors: Jones Richard E. 
Published: September 2010

Obtaining primary wound healing in total joint arthroplasty is essential to a good result. Wound healing problems can occur and the consequences can be devastating. Determination of the host healing capacity can be useful in predicting complications. Cierney and Mader classified patients as type A, no healing compromises; and type B, systemic or local healing compromising factors present. Local factors include traumatic arthritis, multiple previous incisions, extensive scarring, lymphedema, poor vascular perfusion. Systemic compromising factors include diabetes, rheumatic diseases, renal or liver disease, immunocompromise, steroids, smoking, and poor nutrition. In high-risk patients, the surgeon should encourage positive choices such as smoking cessation and nutritional supplementation to elevate the total lymphocyte count and total albumin.
Careful planning of incisions, particularly in patients with scarring or multiple previous operations, is productive. Around the knee the vascular viability is better in the medial flap. Thus, use the most lateral previous incision, do minimal undermining, and handle tissue meticulously. We perform all potentially complicated total knee arthroplasties without tourniquet to enhance blood flow and tissue viability. The use of perioperative anticoagulation will increase wound problems.
If wound drainage or healing problems occur, immediate action is required. Deep sepsis can be ruled out with a joint aspiration and cell count (>2000), differential (>50% polys), and negative culture and sensitivity. All hematomas should be evacuated and necrosis or dehiscence should be managed by debridement to obtain a live wound.
Subcapital Fractures: In the Bucket or On Top of the Neck?
Authors: Kyle Richard F. 
Published: September 2010

Femoral neck fractures have a 30% reoperation rate when internally fixed. To reduce the reoperation rate, the surgeon must accurately decide which fractures are best fixed and which fractures require a prosthesis. The literature supports the fact that nondisplaced fractures should be internally fixed. Fractures in patients physiologically younger than 65 years should also be fixed if they have no comorbidities. The most important factors in reducing failure rate of fixation are patient selection and anatomic reduction. A femoral neck fracture left in varus is doomed to failure and reoperation.
Femoral neck fractures that are displaced in patients older than 65 years require a decision-making algorithm to decide how they should be treated. In the physiologically active patient older than 65 years, internal fixation may be considered. In most patients older than 65 years, prosthetic replacement should be considered. Nursing home patients and patients with comorbidities who are not expected to live longer than 6 to 7 years should receive a hemiarthroplasty. Studies show a high reoperation rate if the patient with hemiarthroplasty survives more than 6 or 7 years.
In the active elderly with little or no comorbidities, a total hip replacement should be considered. This is not only cost effective but provides the best pain relief of any of the treatment options for displaced femoral neck fractures. Treatment of femoral neck fractures remains a challenge, but the surgeon must develop an algorithm to select proper treatment options for the patient. The decision-making process is always shared with the patient.
Dual Mobility for Chronic Hip Instability: A Solution Option
Authors: Stulberg S. David 
Published: September 2010

A dual-mobility acetabular component consists of a large, fixed, porous-coated acetabular component and a bipolar femoral component. These components are often called tripolar components. This configuration provides a stable, well-fixed implant platform against bone and 2 articular interfaces, a large polyethylene surface directly apposed to the highly polished metal shell, and a standard sized (28 mm, 32 mm) femoral head captured within polyethylene.
The dual-mobility cup was designed to reduce the incidence of dislocations in patients at increased risk of instability (eg, patients undergoing revision). The cup appears to offer a safe, effective, durable solution to hip instability. The concept has extensive laboratory and clinical support. Although the long-term durability of dual-mobility cups, particularly in young, active, large patients, is not known, the tested wear rates of the dual-mobility design with the current generation of highly cross-linked polyethylene are significantly lower than any previously reported wear rates. The recently released anatomic dual-mobility cup seeks to reduce the potential for iliopsoas impingement while retaining the stability and wear characteristics of the original dual-mobility design.
Long-Term Monitoring of Age-Related Macular Degeneration with Preferential Hyperacuity Perimetry
Authors: Stur Michael , Manor Yair 
Published: September 2010

Background and Objective:
To estimate the efficacy and usability of preferential hyper-acuity perimetry (PHP) for monitoring patients with high-risk intermediate age-related macular degeneration (AMD).

Patients and Methods:
A long-term, observational, prospective case series of patients with intermediate AMD who underwent fluorescein angiography at recruitment. Eyes were examined every 3 months with PHP, visual acuity, and biomicroscopy. Optical coherence tomography (OCT) imaging was performed when PHP was outside normal limits. In case of suspected findings in OCT, fluorescein angiography was also performed. Patients diagnosed as having choroidal neovascularization (CNV) were offered anti-vascular endothelial growth factor therapy.

Results:
Twenty-six eyes (25 patients) were monitored for a mean follow-up period of 600 days. Of the 172 PHP tests done by these 26 eyes with intermediate AMD, 158 were within normal limits yielding a false-positive rate of 8.1%. Three of 4 eyes that converted to CNV had PHP test results outside normal limits before or on the day of diagnosis.

Conclusion:
PHP is useful for detecting CNV in regularly monitored eyes with intermediate AMD while maintaining a low false-positive rate.
Role of imaging in female infertility [Dr. K.M. Rai Memorial Oration Award]
Authors: Rastogi Rajul 
Published: September 2010

AbstractInfertility in females is multifactorial in origin. Though hysterolaparoscopy is the gold-standard investigation, USG is usually the first-line investigation. MRI has expanded the usefulness of imaging in female infertility. This pictorial essay reviews the role of imaging in the evaluation of female infertility.
Case report: Acute calcific discitis with intravertebral disc herniation in the dorsolumbar spine
Authors: Mittal Puneet , Saggar Kavita , Sandhu Parambir , Gupta Kamini 
Published: September 2010

AbstractAcute calcific discitis is a rare but well-known condition of unknown etiology. In symptomatic cases, the most common site is the cervical spine. We describe the CT scan and MRI findings in a symptomatic patient, with a lesion in the dorsolumbar spine.
Instrumental para la valoración ambiental del medio construido de los asentamientos rurales
Authors: Hernández H 
Published: September 2010

El instrumental contiene un sistema de indicadores, obtenidos de la base del estudio de conceptos y criterios relevantes, y de la caracterización de los asentamientos rurales, que incluye parámetros para evaluar la calidad ambiental del medio construido de los asentamientos rurales. El instrumental diseñado tiene implícito el enfoque sistémico e integral, en aras de alcanzar la sustentabilidad local y fue validado en cinco asentamientos rurales del municipio de Masaya, Nicaragua. El sistema de indicadores se obtuvo de un conjunto de 40 variables significativas, las cuales se interrelacionaron gráficamente tomando en cuenta la teoría de sistemas, y, mediante el proceso por asociación y significado, se obtuvieron 15 indicadores específicos y seis indicadores generales, con su correspondiente sistema categorial. Los resultados de la validación son visualizados en histogramas y matrices. En conclusión, el instrumental permite medir y valorar la calidad ambiental de los asentamientos, evidenciando las carencias y las potencialidades para mejorar las condiciones de vida de sus habitantes. Induce también a orientar el desarrollo integral del asentamiento, así como su desarrollo dentro del sistema territorial. Palabras claves: calidad ambiental; asentamientos rurales; indicadores; valoración ambiental.DOI: http://dx.doi.org/10.5377/nexo.v22i1.38Nexo: Revista Científica Vol.22, No.01, pp.02-09/Agosto 2009
Diseño y montaje de una planta piloto para la extracción de quitina y proteínas
Authors: Escorcia D , Hernández D , Sánchez M , Benevente M 
Published: September 2010

El proyecto se basó en el diseño y montaje de una planta piloto para la extracción química de Quitina y proteínas a partir de desechos de crustáceos (camarón y langostino). Se determinó el contenido de humedad del material y las condiciones experimentales óptimas de volumen y concentración de los reactivos involucrados en el proceso. Además, se realizó un análisis técnico y económico del mismo. Los resultados mostraron que la materia prima tiene un alto contenido de humedad entre 68-80% y que las condiciones experimentales para la obtención de Quitina dependen fuertemente de las características del material. Bajo estas condiciones se obtuvo una recuperación mayor del 98% para el caso de caparazón de camarón y de aproximadamente un 58% en el caso del langostino. Por otro lado, para la extracción de proteínas se encontró que la mayor producción ocurre a pH 4.0 y con soluciones provenientes del proceso de desproteinización, sin trituración previa de la materia prima. El estudio técnico proporcionó información básica sobre los costos e inversión del proceso operativo, datos sobre las instalaciones y los equipos asociados al proceso productivo. El análisis económico mostró que se debe tener una inversión inicial de US $ 10,520.94 para el montaje de la planta piloto y de US $ 4,852.58 para gastos de transporte y operación por seis meses. Palabras claves: caparazón de camarón; langostino; método químico; planta piloto; proteínas, quitina.DOI: http://dx.doi.org/10.5377/nexo.v22i2.42Nexo: Revista Científica Vol. 22, No. 02, pp.45-55/Diciembre 2009
Módulos de entrenamiento para la medición y adquisición de datos (Módulo de visión)
Authors: Mejia I , Gutiérrez J , Moncada V 
Published: September 2010

En este artículo se presenta el proyecto de diseño e implementación de una herramienta de laboratorio, que pretende contribuir a solucionar el déficit existente de medios de entrenamiento para los estudiantes de la carrera de Ingeniería Electrónica de la Universidad Nacional de Ingeniería. El proyecto está enmarcado dentro del área de automatización industrial, específicamente en la adquisición y procesamiento de imágenes. El sistema de Visión Artificial implementado tiene capacidad de permitir la realización de diferentes prácticas en el área de adquisición y procesamiento de imágenes. Entre las aplicaciones que este sistema ofrece se destacan: Detección de fallas en la fabricación de diferentes productos tales como: Fusibles, Integrados con encapsulado HSIP, Objetos circulares, etc; Lectura de códigos de barras; Reconocimiento óptico de caracteres; Supervisión óptica de indicadores digitales (LCD) y analógicos. Los componentes de hardware cumplen con los estándares de la norma IEEE 1394 (Sensor y Hardware de Adquisición) y el software de procesamiento se implementó utilizando la plataforma LabVIEW. Dentro de los componentes del hardware, se diseñaron diferentes escenarios que incluyeron la posición de la cámara y la cantidad de iluminación en función del objeto a inspeccionar y que a su vez garantizó la adquisición adecuada de los datos, lo que permitió evaluar y contrastar sus usos y aplicaciones. Por su parte el software, ejemplifica los diferentes métodos y algoritmos de procesamiento de imágenes, recreando aplicaciones comunes en la industria nicaragüense. Para asegurar el aprovechamiento y uso adecuado del sistema se incluyó la documentación necesaria para conocer el sistema, lo cual es necesario para su correcto uso y mantenimiento. Palabras claves: maquinas de visión; procesamiento de imágenes; control de calidad; adquisición de datos.DOI: http://dx.doi.org/10.5377/nexo.v22i2.43Nexo: Revista Científica Vol. 22, No. 02, pp.56-60/Diciembre 2009
Empresas familiares y estudiantes de ingeniería: Un binomio desaprovechado
Authors: Quintana M 
Published: September 2010

Entre agosto y septiembre de 2009, fue realizado un estudio estadístico para conocer los tipos de empresas familiares vinculadas a estudiantes de carreras tecnológicas que ofrece la Universidad Nacional de Ingeniería (UNI), asimismo, en este estudio se investigó acerca de las herramientas tecnológicas que utilizan tales empresas en apoyo de sus actividades económicas. Con ese propósito, fue elaborado y aplicado un cuestionario entre los alumnos y alumnas que estudian las carreras de ingeniería en Computación, Electrónica y Eléctrica y que a su vez tuviesen alguna relación con empresas familiares (muestra voluntaria). De los resultados se encontró que el 96% del total de empresas consultadas (26 empresas), que son representativas de los distintos sectores económicos del país, utilizan escasamente o no utilizan, herramientas tecnológicas en sus procesos productivos o administrativos. Este resultado reflejó que en la actualidad existe un desaprovechamiento de las capacidades y habilidades que posee un sector de la población con alta formación tecnológica entre el sector de las pequeñas empresas familiares, lo que se manifiesta en la poca utilización de parte de las mismas de la tecnología como herramienta de apoyo en sus actividades productivas o comerciales. Las recomendaciones propuestas en función de estos resultados, han conducido a elaborar un plan de trabajo dirigido a ofrecer dichos servicios tecnológicos con el objetivo de respaldar la labor de este sector empresarial a fin de elevar sus ventajas competitivas. Palabras claves: empresas familiares; universidad; tecnología; pequeñas empresas.DOI: http://dx.doi.org/10.5377/nexo.v22i2.44Nexo Revista Científica Vol. 22, No. 02, pp.61-65/Diciembre 2009
Metodología de modelación de escenarios de riesgo sísmico en Managua, Nicaragua
Authors: Ugarte A 
Published: September 2010

La investigación Metodología de Modelación de Escenarios de Riesgo Sísmico en Managua, Nicaragua fue ejecutada por el proyecto REDUCCION DEL RIESGO SISMICO EN CENTROAMERICA (RESIS II) en su fase II, bajo el auspicio del Centro de Prevención de Desastres en América Central (CEPREDENAC), del cual la Universidad Nacional de Ingeniería (UNI) es parte. Dicha investigación presenta los análisis y resultados de la actualización de la amenaza sísmica, zonificación tectónica y aceleraciones espectrales (PGA) esperadas de Centroamérica y en particular de Managua, Nicaragua. Se presentan formatos de recopilación de información y también algunos ejemplos de los resultados obtenidos de los datos de campo levantados directamente de las edificaciones de viviendas de un barrio de Managua, así como de una extrapolación lograda sobre la base de datos catastrales de la ciudad de Managua. A partir de una muestra de viviendas típicas se establece una clasificación o tipología por cada sistema constructivo a los cuales se les aplico el Método de Análisis Estático No Lineal de Estructuras (PUSHOVER) generándose un análisis de la capacidad de la estructura acorde con una demanda y por ende el punto de desempeño, el cual representa el Máximo Desplazamiento Estructural esperado para un sismo dado y así reflejar el grado de vulnerabilidad. Finalmente, se presenta una guía de usuario del software denominado SELENA (SEismic Losses EstimatioN through a logic tree Aproach) diseñado para aplicarse a esta investigación, con el objetivo de lograr la modelación del riesgo sísmico para Managua. Palabras claves: vulnerabilidad, prevención de desarstres, aceleraciones espectrales, método no lineal.DOI: http://dx.doi.org/10.5377/nexo.v23i1.34Nexo: Revista Científica Vol. 23, No. 01, pp.09-17/Mayo 2010
Una nueva expresión acerca del producto de convolución de la derivada de orden k de la delta de Dirac
Authors: Aguirre M 
Published: September 2010

Palabras claves: distribución; convolución; producto; delta de Dirac; teoría de distribucione AMS Subjet Classification, 46F10, 46F12.DOI: http://dx.doi.org/10.5377/nexo.v23i1.37Nexo: Revista Científica Vol. 23, No. 01, pp.33-39Mayo 2010