2,038 research outputs found
Plastic and Reconstructive Surgery Advance Online Article
Background: The aim of this study was to evaluate the efficacy, safety profile, and complications associated with mandibular distraction osteogenesis performed in infants weighing less than 4 kg with Robin sequence.
Methods: An 11-year retrospective review of all infants (younger than 6 months) with mandibular distraction osteogenesis–treated Robin sequence was performed. Patients weighing less than 4 kg (experimental) and 4 kg or more (control) who underwent mandibular distraction osteogenesis were compared. Demographics, medical comorbidities, improvement in apnea/hypopnea index, need for tracheostomy, repeated distraction, and complications were evaluated.
Results: One hundred twenty-one patients underwent mandibular distraction osteogenesis. Eighty-one patients weighed less than 4 kg and 40 weighed 4 kg or more. The mean follow-up was 2.8 years in patients weighing less than 4 kg and 3.0 years in the control group. Mean age and weight at the time of distraction were 23 days and 3.1 kg, respectively, in the study group; and 2.7 years and 11 kg, respectively, in the control group. There was no significant difference in success of mandibular distraction osteogenesis to treat airway obstruction in the group weighing less than 4 kg compared with the control group (92.6 percent versus 88.9 percent; p = 0.49). The most common complication in each group was surgical-site infection (9.9 percent and 20.0 percent; p = 0.15). Overall complication rates were similar between the two groups (17.3 percent versus 25.0 percent; p = 0.34). The rates of repeated distraction were similar between the two groups (6.3 percent and 13.5 percent; p = 0.28).
Conclusions: Mandibular distraction osteogenesis is a safe and effective treatment modality for infants weighing less than 4 kg with severe airway obstruction. The efficacy, safety, and complication profiles are not significantly different from those of larger patients.
CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III
Nasal Airway and Septal Variation in Unilateral and Bilateral Cleft Lip and Palate
Cleft lip and palate (CLP) affects the dentoalveolar and nasolabial facial regions. Internal and external nasal dysmorphology may persist in individuals born with CLP despite surgical interventions. 7–18 year old individuals born with unilateral and bilateral CLP (n = 50) were retrospectively assessed using cone beam computed tomography. Anterior, middle, and posterior nasal airway volumes were measured on each facial side. Septal deviation was measured at the anterior and posterior nasal spine, and the midpoint between these two locations. Data were evaluated using principal components analysis (PCA), multivariate analysis of variance (MANOVA), and post-hoc ANOVA tests. PCA results show partial separation in high dimensional space along PC1 (48.5% variance) based on age groups and partial separation along PC2 (29.8% variance) based on CLP type and septal deviation patterns. MANOVA results indicate that age (P = 0.007) and CLP type (P ≤ 0.001) significantly affect nasal airway volume and septal deviation. ANOVA results indicate that anterior nasal volume is significantly affected by age (P ≤ 0.001), whereas septal deviation patterns are significantly affected by CLP type (P ≤ 0.001). Age and CLP type affect nasal airway volume and septal deviation patterns. Nasal airway volumes tend to be reduced on the clefted sides of the face relative to non-clefted sides of the face. Nasal airway volumes tend to strongly increase with age, whereas septal deviation values tend to increase only slightly with age. These results suggest that functional nasal breathing may be impaired in individuals born with the unilateral and bilateral CLP deformity
Analysis of Cases inWhich a Biopsy Specimen Is Positive and an Excised Lesion Is Negative for Nonmelanoma Skin Cancer
Nonmelanoma skin cancers (NMSCs), including squamous cell carcinoma (SCC) and basal cell carcinoma (BCC), are the most common types of cancer with the fastest-growing treatment costs in the United States.1 Standard treatment requires biopsy for histologic confirmation, followed by excision. Oftentimes, no residual carcinoma is detected, implying spontaneous clearance at rates reported to vary from 24% to 76%.2- 5 These types of lesions have been investigated by others2- 5 and are not fully understood. Our study aims to determine the lesion and patient characteristics that would most strongly predict a histologically negative result for an excised lesion after a biopsy specimen had positive margins
Surgeon’s and Caregivers’ Appraisals of Primary Cleft Lip Treatment with and without Nasoalveolar Molding: A Prospective Multicenter Pilot Study
Despite the increasing use of nasoalveolar molding (NAM) in early cleft treatment, questions remain about its effectiveness. This study examines clinician and caregiver appraisals of primary cleft lip and nasal reconstruction with and without NAM in a non-randomized, prospective multicenter study
Dynamical Casimir-Polder interaction between an atom and surface plasmons
We investigate the time-dependent Casimir-Polder potential of a polarizable
two-level atom placed near a surface of arbitrary material, after a sudden
change in the parameters of the system. Different initial conditions are taken
into account. For an initially bare ground-state atom, the time-dependent
Casimir-Polder energy reveals how the atom is "being dressed" by virtual,
matter-assisted photons. We also study the transient behavior of the
Casimir-Polder interaction between the atom and the surface starting from a
partially dressed state, after an externally induced change in the atomic level
structure or transition dipoles. The Heisenberg equations are solved through an
iterative technique for both atomic and field operators in the medium-assisted
electromagnetic field quantization scheme. We analyze in particular how the
time evolution of the interaction energy depends on the optical properties of
the surface, in particular on the dispersion relationof surface plasmon
polaritons. The physical significance and the limits of validity of the
obtained results are discussed in detail.Comment: 12 pages, 8 figure
Evaluación de la capacidad reproductiva de sementales bovinos mantenidos en clima tropical húmedo
El objetivo de este estudio fue evaluar la capacidad reproductiva de sementales bovinos y determinar el efecto de factores tales como raza, edad y anormalidad anatómicas dcl aparato reproductor
Células madre pluripotenciales en el tratamiento de la isquemia de miembros inferiores. Primer caso en Paraguay y nuestra experiencia en el Hospital de ClÃnicas de la Universidad Nacional de Asunción
Existe un grupo de pacientes con isquemia crÃtica de miembros inferiores, en los cuales no es posible restablecer una adecuada perfusión sanguÃnea por métodos quirúrgicos o endovasculares y presentan una posibilidad elevada de amputación. En las últimas décadas se han identificado en la médula ósea la existencia de células madre del grupo CD34+, que proliferan ante la presencia de isquemia tisular y migran a través del torrente circulatorio hacia estas zonas, dando origen a arteriolas capilares y vénulas. Este mecanismo suele verse dificultado in vivo por la oclusión de las arterias que irrigan la región afectada. En este trabajo presentamos los resultados de nuestra experiencia en dos pacientes, que fueron sometidos a la extracción mecánica de tejido de su médula ósea, que posteriormente fue filtrado e implantado a lo largo de sus miembros inferiores isquémicos, con el objeto de estimular la neoformación de vasos sanguÃneos para aumentar la perfusión de sangre a estas zonas, cicatrizando sus heridas, evitando de esta manera su amputación
Learning and Reflection in the Midst of Persistent Challenges on Practicing School Leaders’ Time
Among the many scarce resources that principals must conserve and use wisely, time may present one of the more persistent challenges to their leadership practices. A simultaneous and equally challenging practice for school leaders is engaging in systematic reflection that serves to mitigate time constraints and emotional upheavals of the job. Reflection, and resistance to it, emerged as a theme during a yearlong-program that emerged from a school-university partnership, focused on the development of district-level coaches to support experienced principals in becoming more reflective leaders for continuous school improvement. The program uncovered principals’ resistance to the pauses in their practices that reflection requires. These principals and coaches also reported emotional reactions to persisting mandates on school accountability. This paper offers some insights into how reflection may balance the ongoing emotional dynamics and time constraints of schooling, and the degree to which the mentoring program supported principal protégés in this effort
Satisfacción estudiantil de la gestión docente de una universidad pública de Huánuco-Perú
The objective of the research was to determine the relationship between teaching performance and academic satisfaction of students at a public university in Huánuco. It was a study with a correlational quantitative approach. 87 university nursing students were surveyed during 2019. The instruments used were the scales: teaching performance and academic satisfaction, previously validated and reliable. Ethical considerations for research were applied. Descriptive analysis was performed and the bivariate analysis was using the Spearman Rho statistical test for a p value ≤ 0.05 and 95% confidence. In general, the teaching performance perceived by nursing students reached a regular level in 81.6% (71 students), likewise, 12.6% (11 students) indicated good performance and 5.7% poor performance. Regarding academic satisfaction, the medium level prevailed in 87.4% (70) and high satisfaction in 12.6% (11). A positive and significant relationship was obtained between academic satisfaction and competencies: generic and basic specific, compared by Spearman's Rho coefficient whose value was rs = 0.50 with p≤0.000, being statistically significant. In conclusions, a statistically significant moderate relationship was observed between teaching performance and academic satisfaction of university students, showing that the higher the teaching performance, the higher the student satisfaction (p ≤ 0.05).El objetivo de la investigación fue determinar la relación entre el desempeño docente y la satisfacción académica de los estudiantes de una universidad pública de Huánuco. Fue un estudio de enfoque cuantitativo de tipo correlacional. Se encuestó a 87 estudiantes universitarios de enfermerÃa durante el 2019. Los instrumentos utilizados fueron las escalas: desempeño docente y satisfacción académica, previamente validada y fiabilizadas. Se aplicaron las consideraciones éticas para la investigación. Se realizó análisis descriptivo y el análisis bivariado fue mediante la prueba estadÃstica Rho de Spearman para un valor p ≤ 0,05 y 95% de confianza. En general, el desempeño docente percibida por los estudiantes de enfermerÃa, alcanzó un nivel regular en 81,6% (71 estudiantes), asimismo, 12,6% (11 estudiantes) señalaron buen desempeño y 5,7% desempeño deficiente. En relación a la satisfacción académica, predominó e3l nivel medio en 87,4% (70) y satisfacción alta en 12,6% (11). Se obtuvo relación positiva y significativa entre la satisfacción académica y las competencias: especÃficas genéricas y básicas, confrontado por el coeficiente Rho de Spearman cuyo valor fue rs = 0,50 con p≤0,000, siendo estadÃsticamente significativa. En conclusiones se observó relación moderada estadÃsticamente significativa entre el desempeño docente y la satisfacción académica de los estudiantes universitarios, evidenciándose que a mayor desempeño docente, es mayor la satisfacción estudiantil (p ≤ 0,05)
Microstructure and mechanical properties of 5.8 GHz microwave-sintered ZrO2/Al2O3 ceramics
[EN] Aim of the present study is to sinter zirconia nanocomposite powders doped with ceria and toughened with alumina (10Ce-TZP/Al2O3) by non-conventional means, i.e. microwave sintering technology. The sintering effects of various microwave applicators and frequency generators were evaluated using an optimised experimental set-up. The microwave-sintered samples were compared with the composites sintered by the conventional method. The mechanical properties of the ceramic composites were evaluated by their hardness, fracture toughness and Young's modulus. Likewise, their density and microstructure were analysed.The authors thank the Generalitat Valenciana for the financial support provided to the PROMETEU/2016/040 project. A. Borrell is grateful to the Spanish Ministry of Economy and Competitiveness for her RyC contract (RYC-2016-20915).Gil-Flores, L.; Salvador Moya, MD.; Penaranda-Foix, FL.; Fernández, A.; Suárez-Menéndez, M.; Rosa, R.; Veronesi, P.... (2019). Microstructure and mechanical properties of 5.8 GHz microwave-sintered ZrO2/Al2O3 ceramics. Ceramics International. 45(14):18059-18064. https://doi.org/10.1016/j.ceramint.2019.06.026S1805918064451
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