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1.
Aesthet Surg J Open Forum ; 6: ojae040, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39015113

RESUMEN

Background: The standard treatment for rectus diastasis is rectus sheath plication during abdominoplasty. Lasting correction of diastasis is essential, but there is currently a debate as to whether absorbable or nonabsorbable rectus plication achieves a lower rate of recurrence. Objectives: The goal of this study is to assess long-term patient outcomes and the recurrence of rectus diastasis after plication with long-lasting absorbable sutures. Methods: A retrospective study of abdominoplasties performed by the senior author between 2018 and 2022 was performed. Only female patients with >6 months of follow-up were included. Plication of the rectus muscles was performed with a combination of interrupted, buried, figure of eight #0 polydioxanone suture and running #0 Maxon (Covidien, Mansfield, MA). Outcomes were assessed by physical examination at postoperative visits. A retrospective chart review was used to obtain demographic and perioperative information. Results: Seventy-one patients underwent abdominoplasty with an average follow-up of 21.1 months. The average age was 43 years, and the average BMI was 27 kg/m2. Correction of rectus diastasis was performed using absorbable sutures in all patients with no recurrence of diastasis in any patient (0% diastasis recurrence rate). Complications included delayed wound healing (11%), seroma (8.5%), hematoma (2.8%), and deep vein thrombosis/pulmonary embolism (2.8%). No patients needed reoperation. Conclusions: Abdominal wall plication using a double-layered, long-lasting absorbable suture closure is a safe, reliable, and effective method to address rectus diastasis during abdominoplasty. Our technique achieved no recurrence of diastasis in any patient and a low complication profile.

2.
Aesthet Surg J ; 44(9): NP654-NP660, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-38669208

RESUMEN

BACKGROUND: Abdominoplasty procedures continue to evolve because combining techniques such as suction-assisted lipectomy or direct subscarpal lipectomy have proven to be powerful adjuncts to achieve optimal aesthetic results. However, concern has been expressed about combining techniques simultaneously given the potential to damage the vascularity of the abdominoplasty flap. OBJECTIVES: The aim of this study was to assess the safety and efficacy of simultaneous direct subscarpal lipectomy combined with liposuction in abdominoplasty patients. METHODS: A 4-year retrospective review of consecutive abdominoplasties (n = 200) performed by a single surgeon was conducted. Liposuction of the abdominal flap and flanks was performed in all patients. After raising the abdominoplasty flap, undermining was performed to just beyond the xyphoid, the lower rib margins superiorly, and the anterior axillary line laterally. Fat deep to Scarpa's fascia was then removed by direct tangential excision in all zones of the abdominal flap. RESULTS: The patients had a mean age of 42.19 years and BMI of 28.10 kg/m2; the mean follow-up time was 7 months. Seroma occurred in 13 patients (6.5%), superficial wound dehiscence treated with local wound care in 16 patients (8%), hypertrophic scarring in 16 patients (8%), partial umbilical necrosis in 1 patient (0.5%), and partial umbilical epidermolysis in 6 patients (3%). No patients experienced major or minor full-thickness tissue loss. No patients needed reoperation. CONCLUSIONS: Simultaneous direct excision of subscarpal fat with liposuction of the abdomen and flanks does not appear to subject any zone of the abdominoplasty flap to increased risks of vascular compromise. No flap necroses were observed. The technique described is safe and may provide superior abdominoplasty results.


Asunto(s)
Abdominoplastia , Lipectomía , Humanos , Femenino , Estudios Retrospectivos , Adulto , Abdominoplastia/efectos adversos , Abdominoplastia/métodos , Persona de Mediana Edad , Lipectomía/métodos , Lipectomía/efectos adversos , Masculino , Resultado del Tratamiento , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Adulto Joven , Colgajos Quirúrgicos/efectos adversos , Colgajos Quirúrgicos/trasplante , Anciano , Estética , Estudios de Seguimiento
4.
Urol Res Pract ; 49(2): 96-99, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37877855

RESUMEN

The size of adrenal incidentalomas has important implications for diagnosis and management. Recommendations from endocrine societies do not all correlate with regard to adrenal incidentaloma size. Therefore, the aim was to compare adrenal incidentaloma size recommendations between different endocrine societies and the reasoning for these recommendations. Eight different international guidelines were reviewed and compared. The smaller the size of the incidentaloma, the lower the risk for malignancy. The majority of guidelines consider 4 cm as the cut-off, but there are discrepancies. Size indications for laparoscopic adrenalectomy have a wide range from less than 4 cm up to 12 cm. The followup period of adrenal incidentalomas, as well as what is considered significant growth over that period, varies between the recommendations. Therefore, the clinician should be aware of the differences when managing a patient with adrenal incidentaloma. There are discrepancies in size considerations with regard to significance, treatment options, optimal follow-up period, and further management.

5.
Langenbecks Arch Surg ; 408(1): 328, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37612518

RESUMEN

PURPOSE: Factors predicting morbidity and mortality in patients with colon-related gunshot injuries and the management of these injuries are not always straightforward. This aimed to assess the impact of abdominal gunshot wounds with colonic injuries on patients' overall outcomes. METHODS: This cross-sectional prospective observational study compared patients with colon injuries and without colon injuries. Data was collected from admission, theatre and postoperative care. Patients were recruited between 1 January 2020 and 20 October 2021. RESULTS: Of 132 patients with abdominal gunshot injuries, 71 (54.0%) had colon injuries. The colon injury group had a higher incidence of laparotomy wound sepsis (p<0.0001), bullet exit wound infection (p<0.0001), tract necrotizing fasciitis (p<0.0001), relook laparotomies (p<0.0001) and a longer hospital stay (p<0.0001). Septicaemia (p=0.002) or anastomotic leak (p=0.041) was associated with a penetrating abdominal trauma index (PATI) ≥25. Most patients who developed tract necrotizing fasciitis did not have their tract debrided/ lavaged (p=0.004). The type of colon repair did not influence the length of hospital stay (p=0.688) or the development of a colon-related complication (p=0.578). Between 18 and 25 years (p<0.0001) and >2 organs injured (p=0.018) were associated with colon-related complications. Patients between 18 and 25 years were 4.748 times more likely to develop a colon-related complication (p=0.046). CONCLUSION: Gunshot wounds to the abdomen with associated colonic injuries had a worse outcome with an increased risk of developing wound infections. There is no difference in the operative management of colonic injury. Patients between the ages of 18 and 25 years or >2 organs injured are more likely to develop a complication.


Asunto(s)
Traumatismos Abdominales , Fascitis Necrotizante , Heridas por Arma de Fuego , Humanos , Adolescente , Adulto Joven , Adulto , Heridas por Arma de Fuego/complicaciones , Heridas por Arma de Fuego/cirugía , Estudios Transversales , Abdomen , Traumatismos Abdominales/complicaciones , Traumatismos Abdominales/cirugía , Colon/cirugía
6.
Front Transplant ; 2: 1184620, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38993873

RESUMEN

Background: Donation after circulatory death (DCD) liver allografts are associated with higher rates of primary non-function (PNF) and ischemic cholangiopathy (IC). Advanced recovery techniques, including thoracoabdominal normothermic regional perfusion (TA-NRP), may improve organ utilization and patient and allograft outcomes. Given the increasing US experience with TA-NRP DCD recovery, we evaluated outcomes of DCD liver allografts transplanted after TA-NRP. Methods: Liver allografts transplanted from DCD donors after TA-NRP were identified from 5/1/2021 to 1/31/2022 across 8 centers. Donor data included demographics, functional warm ischemic time (fWIT), total warm ischemia time (tWIT) and total time on TA-NRP. Recipient data included demographics, model of end stage liver disease (MELD) score, etiology of liver disease, PNF, cold ischemic time (CIT), liver function tests, intensive care unit (ICU) and hospital length of stay (LOS), post-operative transplant related complications. Results: The donors' median age was 32 years old and median BMI was 27.4. Median fWIT was 20.5 min; fWIT exceeded 30 min in two donors. Median time to initiation of TA-NRP was 4 min and median time on bypass was 66 min. The median recipient listed MELD and MELD at transplant were 22 and 21, respectively. Median allograft CIT was 292 min. The median length of follow up was 257 days. Median ICU and hospital LOS were 2 and 7 days, respectively. Three recipients required management of anastomotic biliary strictures. No patients demonstrated IC, PNF or required re-transplantation. Conclusion: Liver allografts from TA-NRP DCD donors demonstrated good early allograft and recipient outcomes.

7.
Polymers (Basel) ; 14(8)2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35458336

RESUMEN

Fused deposition modeling (FDM) 3D printing is the most common type of additive manufacturing available in both research and the industry. Due to the rapid development of 3D printing, there is now a significant need to fabricate parts with higher quality with respect to cosmetics, precision, and strength of the final products. This work is focused on finding the optimal printing condition for a commercially available 3D printer and filament material (i.e., Polylactic acid (PLA)). In this work, we focus on finding the combined effect of retraction speed, deposition angle, and number of walls on both the visual quality and strength of 3D-printed parts. It is found that the number of walls does not play a major role in the strength of the parts. On the other hand, the retraction speed plays a significant role in defining the ultimate tensile strength of the parts. For parts printed at higher retraction speeds, there is a 10-15% improvement in the ultimate tensile strength.

8.
JPRAS Open ; 31: 32-49, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34926777

RESUMEN

BACKGROUND: Post-mastectomy pain syndrome (PMPS) is a surgical complication of breast surgery characterized by chronic neuropathic pain. The development of PMPS is multifactorial and research on its prevention is limited. The objective of this systematic review is to synthesize the existing evidence on interventions for lowering the incidence of persistent neuropathic pain after breast surgery. METHODS: Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we performed a comprehensive search of the electronic databases of MEDLINE, Cochrane Library, Embase, CINAHL, PsycINFO, Web of Science, and ClinicalTrials.gov using a combination of database-specific controlled vocabulary and keyword searches. Two reviewers independently screened all unique records. Publications on chronic (>3-month duration) pain after breast cancer-related surgery were included. Studies were classified by modality. RESULTS: Our literature search yielded 7092 articles after deduplication. We identified 45 studies that met final inclusion criteria for analysis, including 37 randomized-controlled trials. These studies revealed seven major intervention modalities for prevention of PMPS: physical therapy, mindfulness-based cognitive therapy, oral medications, surgical intervention, anesthesia, nerve blocks, and topical medication therapy. CONCLUSION: High-quality data on preventative techniques for PMPS are required to inform decisions for breast cancer survivors. We present a comprehensive assessment of the modalities available that can help guide breast and reconstructive surgeons employ effective strategies to lower the incidence and severity of PMPS. Our review supports the use of multimodal care involving both a peripherally targeted treatment and centrally acting medication to prevent the development of PMPS.

9.
BMJ Case Rep ; 14(5)2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33972293

RESUMEN

The association of pheochromocytoma in patients with neurofibromatosis type I has rarely been reported in low-income countries, especially on the African continent. A 43-year-old woman with neurofibromatosis type I was diagnosed with a right adrenal pheochromocytoma in Pretoria, South Africa. To our knowledge, this report is the first case to be published of a patient with neurofibromatosis type I diagnosed with a pheochromocytoma in Pretoria, and one of three cases on the African continent. The rarity may be due to the two associated conditions being under-reported, undiagnosed, misdiagnosed or possibly the association is rare on the African continent. The clinician dealing with these two conditions should be aware of the association.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Neurofibromatosis 1 , Feocromocitoma , Neoplasias de las Glándulas Suprarrenales/complicaciones , Neoplasias de las Glándulas Suprarrenales/diagnóstico por imagen , Neoplasias de las Glándulas Suprarrenales/epidemiología , Adulto , Femenino , Humanos , Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/diagnóstico , Feocromocitoma/complicaciones , Feocromocitoma/epidemiología , Sudáfrica
10.
PLoS One ; 16(4): e0249826, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33909647

RESUMEN

Billions of birds fatally collide with human-made structures each year. These mortalities have consequences for population viability and conservation of endangered species. This source of human-wildlife conflict also places constraints on various industries. Furthermore, with continued increases in urbanization, the incidence of collisions continues to increase. Efforts to reduce collisions have largely focused on making structures more visible to birds through visual stimuli but have shown limited success. We investigated the efficacy of a multimodal combination of acoustic signals with visual cues to reduce avian collisions with tall structures in open airspace. Previous work has demonstrated that a combination of acoustic and visual cues can decrease collision risk of birds in captive flight trials. Extending to field tests, we predicted that novel acoustic signals would combine with the visual cues of tall communication towers to reduce collision risk for birds. We broadcast two audible frequency ranges (4 to 6 and 6 to 8 kHz) in front of tall communication towers at locations in the Atlantic migratory flyway of Virginia during annual migration and observed birds' flight trajectories around the towers. We recorded an overall 12-16% lower rate of general bird activity surrounding towers during sound treatment conditions, compared with control (no broadcast sound) conditions. Furthermore, in 145 tracked "at-risk" flights, birds reduced flight velocity and deflected flight trajectories to a greater extent when exposed to the acoustic stimuli near the towers. In particular, the 4 to 6 kHz stimulus produced the greater effect sizes, with birds altering flight direction earlier in their trajectories and at larger distances from the towers, perhaps indicating that frequency range is more clearly audible to flying birds. This "acoustic lighthouse" concept reduces the risk of collision for birds in the field and could be applied to reduce collision risk associated with many human-made structures, such as wind turbines and tall buildings.


Asunto(s)
Estimulación Acústica/métodos , Migración Animal , Aves/fisiología , Arquitectura y Construcción de Instituciones de Salud/métodos , Sonido , Conducta Espacial , Animales , Percepción Auditiva , Señales (Psicología) , Estimulación Luminosa , Percepción Visual
11.
Retrovirology ; 17(1): 14, 2020 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-32571345

RESUMEN

BACKGROUND: Patients infected with the human immunodeficiency virus (HIV) are more prone to systemic inflammation and pathological clotting, and many may develop deep vein thrombosis (DVT) as a result of this dysregulated inflammatory profile. Coagulation tests are not routinely performed unless there is a specific reason. METHODS: We recruited ten healthy control subjects, 35 HIV negative patients with deep vein thrombosis (HIV negative-DVT), and 13 HIV patients with DVT (HIV positive-DVT) on the primary antiretroviral therapy (ARV) regimen-emtricitabine, tenofovir and efavirenz. Serum inflammatory markers, haematological results, viscoelastic properties using thromboelastography (TEG) and scanning electron microscopy (SEM) of whole blood (WB) were used to compare the groups. RESULTS: The DVT patients (HIV positive and HIV negative) had raised inflammatory markers. The HIV positive-DVT group had anaemia in keeping with anaemia of chronic disorders. DVT patients had a hypercoagulable profile on the TEG but no significant difference between HIV negative-DVT and HIV positive-DVT groups. The TEG analysis compared well and supported our ultrastructural results. Scanning electron microscopy of DVT patient's red blood cells (RBCs) and platelets demonstrated inflammatory changes including abnormal cell shapes, irregular membranes and microparticle formation. All the ultrastructural changes were more prominent in the HIV positive-DVT patients. CONCLUSIONS: Although there were trends that HIV-positive patients were more hypercoagulable on functional tests (viscoelastic profile) compared to HIV-negative patients, there were no significant differences between the 2 groups. The sample size was, however, small in number. Morphologically there were inflammatory changes in patients with DVT. These ultrastructural changes, specifically with regard to platelets, appear more pronounced in HIV-positive patients which may contribute to increased risk for hypercoagulability and deep vein thrombosis.


Asunto(s)
Coagulación Sanguínea , Infecciones por VIH/sangre , Infecciones por VIH/complicaciones , Trombosis de la Vena/patología , Adulto , Anciano , Anciano de 80 o más Años , Terapia Antirretroviral Altamente Activa , Estudios de Casos y Controles , Femenino , Infecciones por VIH/tratamiento farmacológico , Humanos , Inflamación/etiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Trombosis de la Vena/virología , Adulto Joven
12.
Semin Thromb Hemost ; 45(2): 132-140, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30566969

RESUMEN

The number of people infected with human immunodeficiency virus (HIV) is rapidly increasing and the majority of those infected are living in sub-Saharan Africa. Some hallmarks of HIV are inflammation and upregulation of inflammatory markers. A pathological coagulation system may accompany these inflammatory changes and potentially result in venous thromboembolism such as a deep vein thrombosis (DVT). In this review, the authors describe the inflammatory profile in HIV, the treatment regimens currently in place in South Africa, and in particular how HIV affects the hematological system, with specific focus on platelets, red blood cells (RBCs; erythrocytes), and fibrin(ogen). They also discuss the presence of DVT in HIV, focus on screening tests, and suggest a more proactive approach to track the inflammatory profile of HIV patients, by specifically using parameters that might point to pathological coagulation; these should involve platelet, RBC, and fibrin(ogen) analysis. They conclude by suggesting that including coagulation function tests to study the effect of treatment interventions would improve outcomes in these individuals, as it could help in the diagnosis of thromboembolic disease. Furthermore, this approach could streamline treatment strategies due to improved monitoring. A better understanding of hypercoagulability of HIV-infected patients is therefore urgently needed. In conclusion, the authors suggest a panel of pathology tests that should be considered as standard procedures when HIV is present.


Asunto(s)
Trastornos de la Coagulación Sanguínea/complicaciones , Infecciones por VIH/complicaciones , Tromboembolia Venosa/complicaciones , Trombosis de la Vena/complicaciones , África Austral , Fármacos Anti-VIH/uso terapéutico , Recuento de Células Sanguíneas , Trastornos de la Coagulación Sanguínea/diagnóstico , Pruebas de Coagulación Sanguínea/métodos , Fibrina/metabolismo , Infecciones por VIH/tratamiento farmacológico , Humanos , Tromboembolia Venosa/diagnóstico , Trombosis de la Vena/diagnóstico
13.
Medicine (Baltimore) ; 97(50): e13634, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30558052

RESUMEN

BACKGROUND: The work-up of a thyroid nodule to diagnose malignancy is not always straightforward. There are various international thyroid societies each with their own guidelines on the approach to a thyroid nodule. The aim is therefore to determine whether a clinically suspicious thyroid nodule should be subjected to surgery. METHOD: A review of various international thyroid society guidelines on their approach to a suspicious thyroid nodule. RESULTS: Sixty-two relevant articles were identified of which 4 current international thyroid guidelines, consisting of 6 different international societies, were reviewed. The commonalities of each of the thyroid society guidelines are imaging, with ultrasound, and cytopathology as the main diagnostic investigations. The description and the size of the nodule are the 2 most important factors on ultrasound; however, the guidelines vary in their recommendations whether to biopsy a suspicious thyroid nodule. An indeterminate group exists whereby thyroid nodules cannot be confirmed as malignant even with fine needle aspiration cytology (FNA). Although further investigations (Technetium-99m -sestamethoxyisobutylisonitryl scan, 18F-fluorodeoxyglucose positron emission tomography/computed tomography scan, and molecular testing) may assist in the diagnosis, there are limitations. There are differences in the guidelines whether suspicious nodules should be subjected to surgery. CONCLUSION: Ultrasound and cytopathology are the 2 most appropriate investigations to diagnose whether a suspicious thyroid nodule is benign or malignant. The clinician needs to be aware of the differences between the guidelines from the various international thyroid societies, specifically concerning the indeterminate group of patients where a definitive diagnosis cannot be made. Management decisions should be discussed with a thyroid multidisciplinary team for a consensus decision whether or not to subject a patient with a suspicious thyroid nodule to surgery.


Asunto(s)
Citodiagnóstico/métodos , Neoplasias de la Tiroides/diagnóstico , Nódulo Tiroideo , Tiroidectomía/métodos , Tiempo de Tratamiento , Ultrasonografía/métodos , Humanos , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/patología , Nódulo Tiroideo/cirugía
14.
J Reconstr Microsurg ; 34(5): 327-333, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29452439

RESUMEN

BACKGROUND: Free tissue transfer is one option for preservation of form and function in the native limb, in the setting of soft tissue paucity. However, the data on patient functionality after microvascular intervention is inconsistently reported. The Lower Extremity Function Scale (LEFS) measures patient-reported difficulty in carrying out 20 physical activities, on a Likert scale, the sum of which correlates with descriptive functional stages of 1-5. We assess limb functionality in this cohort of microvascular patients using the LEFS survey. METHODS: A retrospective chart review was conducted at a single academic medical center of 101 consecutive free flaps, from 2011 to 2016. Of the flaps that met inclusion criteria, 39 had completed LEFS surveys. Mean LEFS scores were calculated, and the effects of risk factors such as diabetes, age, and smoking status were analyzed. RESULTS: The mean LEFS score after free tissue transfer was 50.3 (SD ± 21.1), with a mean follow up survey time of 3.0 years (SD ± 1.3). The score correlated with Stage 4 function, or "independent community ambulation," and age was the only demographic factor associated with decreased functionality in this group. This is compared with mean LEFS score of 43.1 (SD ± 18.4) in cohort of 55 below knee amputations (BKAs), and 38.3 (SD ± 14.9) in 28 above knee amputations (AKAs), both correlating with Stage 3 function: "limited community ambulation." CONCLUSIONS: Functional outcomes scores such as the LEFS demonstrate that patients can obtain an adequate level of functionality for independent community activity after free tissue transfer, although functional improvement diminishes with age.


Asunto(s)
Actividades Cotidianas , Muñones de Amputación/cirugía , Evaluación de la Discapacidad , Colgajos Tisulares Libres/trasplante , Procedimientos de Cirugía Plástica/métodos , Centros Médicos Académicos , Adulto , Anciano , Amputados/rehabilitación , Estudios de Cohortes , Femenino , Fémur/cirugía , Estudios de Seguimiento , Humanos , Modelos Lineales , Extremidad Inferior/cirugía , Masculino , Persona de Mediana Edad , Recuperación de la Función/fisiología , Estudios Retrospectivos , Medición de Riesgo , Tibia/cirugía , Resultado del Tratamiento , Cicatrización de Heridas/fisiología , Heridas y Lesiones/cirugía
15.
Integr Comp Biol ; 57(2): 217-230, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28662566

RESUMEN

SYNOPSIS: Flight is the defining characteristic of birds, yet the mechanisms through which flight ability develops are only beginning to be understood. Wing-assisted incline running (WAIR) and controlled flapping descent (CFD) are behaviors that may offer significant adaptive benefits to developing birds. Recent research into these forms of locomotion has focused on species with precocial development, with a particularly rich data set from chukar partridge (Alectoris chukar). Here we briefly review the kinematics and aerodynamics of flight development in this species. We then present novel measurements of the development of pectoralis contractile behavior during the ontogenetic transition toward powered flight. To obtain these new empirical data, we used indwelling electromyography (EMG) and sonomicrometry and tested WAIR and CFD in seven age classes of chukar (n = 2-4 birds per age) from 5 days post hatching (dph) to adult (300+ dph). For each age class, we measured muscle activity during maximal performance, which was WAIR at 65° in birds 5 dph, CFD in birds 9 dph, WAIR at 80° in birds 14 dph, level flight in birds 25-61 dph, and ascending flight in adults. We also measured muscle activity during sub-maximal performance in all age classes. Flapping chukar chicks use near-continuous activation of their pectoralis at relatively low electromyography amplitudes for the first 8 days and progress to stereotypic higher-amplitude activation bursts by Day 12. The pectoralis undergoes increasing strain at higher strain rates with age, and length trajectory becomes more asymmetrical with greater variation in contractile velocity within the shortening phase of individual contractions. At 20-25 days (12-15% adult chukar mass), pectoralis activity and locomotor performance approaches that of adults, although strain rate exhibits a temporary decrease at 61 dph concurrent with using newly-replaced primary feathers. To better understand how these patterns relate to the evolution of life-history strategy and locomotion, we encourage future efforts to explore these behaviors in altricial and semi-altricial bird species.


Asunto(s)
Vuelo Animal/fisiología , Galliformes/fisiología , Músculos Pectorales/fisiología , Animales , Evolución Biológica , Fenómenos Biomecánicos , Músculos Pectorales/anatomía & histología , Carrera/fisiología , Alas de Animales/fisiología
16.
Biol Open ; 5(9): 1334-42, 2016 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-27444791

RESUMEN

Ecological, behavioral and biomechanical studies often need to quantify animal movement and behavior in three dimensions. In laboratory studies, a common tool to accomplish these measurements is the use of multiple, calibrated high-speed cameras. Until very recently, the complexity, weight and cost of such cameras have made their deployment in field situations risky; furthermore, such cameras are not affordable to many researchers. Here, we show how inexpensive, consumer-grade cameras can adequately accomplish these measurements both within the laboratory and in the field. Combined with our methods and open source software, the availability of inexpensive, portable and rugged cameras will open up new areas of biological study by providing precise 3D tracking and quantification of animal and human movement to researchers in a wide variety of field and laboratory contexts.

17.
PLoS One ; 11(4): e0153446, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27100994

RESUMEN

Some of the greatest transformations in vertebrate history involve developmental and evolutionary origins of avian flight. Flight is the most power-demanding mode of locomotion, and volant adult birds have many anatomical features that presumably help meet these demands. However, juvenile birds, like the first winged dinosaurs, lack many hallmarks of advanced flight capacity. Instead of large wings they have small "protowings", and instead of robust, interlocking forelimb skeletons their limbs are more gracile and their joints less constrained. Such traits are often thought to preclude extinct theropods from powered flight, yet young birds with similarly rudimentary anatomies flap-run up slopes and even briefly fly, thereby challenging longstanding ideas on skeletal and feather function in the theropod-avian lineage. Though skeletons and feathers are the common link between extinct and extant theropods and figure prominently in discussions on flight performance (extant birds) and flight origins (extinct theropods), skeletal inter-workings are hidden from view and their functional relationship with aerodynamically active wings is not known. For the first time, we use X-ray Reconstruction of Moving Morphology to visualize skeletal movement in developing birds, and explore how development of the avian flight apparatus corresponds with ontogenetic trajectories in skeletal kinematics, aerodynamic performance, and the locomotor transition from pre-flight flapping behaviors to full flight capacity. Our findings reveal that developing chukars (Alectoris chukar) with rudimentary flight apparatuses acquire an "avian" flight stroke early in ontogeny, initially by using their wings and legs cooperatively and, as they acquire flight capacity, counteracting ontogenetic increases in aerodynamic output with greater skeletal channelization. In conjunction with previous work, juvenile birds thereby demonstrate that the initial function of developing wings is to enhance leg performance, and that aerodynamically active, flapping wings might better be viewed as adaptations or exaptations for enhancing leg performance.


Asunto(s)
Vuelo Animal , Galliformes/fisiología , Huesos de la Pierna/fisiología , Alas de Animales/fisiología , Animales , Fenómenos Biomecánicos , Huesos de la Pierna/anatomía & histología , Tomografía Computarizada por Rayos X , Alas de Animales/anatomía & histología
18.
J Leg Med ; 35(3): 385-422, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25207630

RESUMEN

This document was judged Best Brief submitted to the 2013­2014 National Health Law Moot Court Competition. The brief was submitted by students Jessica Robinson DeShon, Brandon Jackson, and Matthew Ward on behalf of Faulkner University School of Law in Montgomery, Alabama. Address correspondence to Professor Joe Lester at Jlester@Faulkner.edu.


Asunto(s)
Confidencialidad/legislación & jurisprudencia , Disentimientos y Disputas/legislación & jurisprudencia , Política de Salud/legislación & jurisprudencia , Hospitales Universitarios/legislación & jurisprudencia , Privilegios del Cuerpo Médico/legislación & jurisprudencia , Garantía de la Calidad de Atención de Salud/legislación & jurisprudencia , Medios de Comunicación Sociales/legislación & jurisprudencia , Vacunación/efectos adversos , Vacunación/legislación & jurisprudencia , Humanos , Illinois , Lactante , Masculino , Organizaciones de Normalización Profesional/legislación & jurisprudencia
19.
J Exp Biol ; 217(Pt 15): 2717-25, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24855672

RESUMEN

Cliff swallows (Petrochelidon pyrrhonota) are highly maneuverable social birds that often forage and fly in large open spaces. Here we used multi-camera videography to measure the three-dimensional kinematics of their natural flight maneuvers in the field. Specifically, we collected data on tandem flights, defined as two birds maneuvering together. These data permit us to evaluate several hypotheses on the high-speed maneuvering flight performance of birds. We found that high-speed turns are roll-based, but that the magnitude of the centripetal force created in typical maneuvers varied only slightly with flight speed, typically reaching a peak of ~2 body weights. Turning maneuvers typically involved active flapping rather than gliding. In tandem flights the following bird copied the flight path and wingbeat frequency (~12.3 Hz) of the lead bird while maintaining position slightly above the leader. The lead bird turned in a direction away from the lateral position of the following bird 65% of the time on average. Tandem flights vary widely in instantaneous speed (1.0 to 15.6 m s(-1)) and duration (0.72 to 4.71 s), and no single tracking strategy appeared to explain the course taken by the following bird.


Asunto(s)
Vuelo Animal , Golondrinas/fisiología , Animales , Conducta Animal , Fenómenos Biomecánicos , Grabación en Video , Alas de Animales/fisiología
20.
J Exp Biol ; 217(Pt 11): 1843-8, 2014 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-24577444

RESUMEN

Stereo videography is a powerful technique for quantifying the kinematics and behavior of animals, but it can be challenging to use in an outdoor field setting. We here present a workflow and associated software for performing calibration of cameras placed in a field setting and estimating the accuracy of the resulting stereoscopic reconstructions. We demonstrate the workflow through example stereoscopic reconstructions of bat and bird flight. We provide software tools for planning experiments and processing the resulting calibrations that other researchers may use to calibrate their own cameras. Our field protocol can be deployed in a single afternoon, requiring only short video clips of light, portable calibration objects.


Asunto(s)
Vuelo Animal , Fotogrametría/métodos , Programas Informáticos , Grabación en Video/métodos , Animales , Fenómenos Biomecánicos , Calibración , Quirópteros , Imagenología Tridimensional , Golondrinas
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