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One of the most basic notions in physics is the partitioning of a system into subsystems and the study of correlations among its parts. In this Letter, we explore this notion in the context of quantum reference frame (QRF) covariance, in which this partitioning is subject to a symmetry constraint. We demonstrate that different reference frame perspectives induce different sets of subsystem observable algebras, which leads to a gauge-invariant, frame-dependent notion of subsystems and entanglement. We further demonstrate that subalgebras which commute before imposing the symmetry constraint can translate into noncommuting algebras in a given QRF perspective after symmetry imposition. Such a QRF perspective does not inherit the distinction between subsystems in terms of the corresponding tensor factorizability of the kinematical Hilbert space and observable algebra. Since the condition for this to occur is contingent on the choice of QRF, the notion of subsystem locality is frame dependent.
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PURPOSE: Initial studies of combinations of radioiodine therapy (RIT) and local ablative procedures for the treatment of thyroid nodules have shown promising results. The goal of this study was to evaluate the effectiveness of RIT combined with radiofrequency ablation (RFA) in patients with goitres and to determine which ablative procedure is the most suitable for a combined therapy. METHODS: Thirty patients with goitres were divided into two subgroups. A test group of 15 patients received combined therapy (RIT + RFA) and a control group of 15 patients received RIT mono therapy. All patients underwent assessments including ultrasound, laboratory evaluation (T3, T4, TSH, TG, TPOAb, TgAbTRAb) and scintigraphic imaging with Tc-99m-Pertechnetate. The 3-month volume reduction was used to evaluate therapy effectiveness. RESULTS: Combined therapy (subgroup 1) resulted in a significant (p < 0.05) thyroid volume reduction (22.3 ± 54 ml/32.2 ± 58.2%) with better performance (p > 0.05) than the control group (20.2 ± 32.2 ml/29.6 ± 42.1%). All patients became euthyroid after treatment. No major discomfort or complications occurred. A review of the literature investigating combinations of other local ablative procedures with RIT was performed to determine the most promising combination. CONCLUSIONS: The present study confirms the positive experiences with the combined therapy of RIT and local ablative procedures shown in the current literature and approves this approach for the treatment of goitres with RFA + RIT. These findings, when confirmed by further studies, should expand the indication of combined therapy as a minimally invasive alternative to surgery.
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Ablación por Catéter , Bocio/terapia , Radioisótopos de Yodo/uso terapéutico , Anciano , Terapia Combinada , Femenino , Bocio/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Tiroxina , TriyodotironinaRESUMEN
PURPOSE: Radiofrequency ablation (RFA) is an approved minimal invasive method for the treatment of benign thyroid nodules. Several experimental, mainly ex vivo animal studies have compared the effectiveness of different RFA procedures in liver tissue. The aim of this retrospective clinical study was to evaluate the difference between monopolar and bipolar RFA in thyroid tissue considering thyroid volume reduction, patient discomfort and ultrasound evaluation. METHODS: Eighteen patients with symptomatic complex benign thyroid nodules were treated in a single RFA session. Nine patients were treated with monopolar RFA, and nine other patients were treated with bipolar RFA. All patients underwent assessments before therapy and at 3-month follow-up (3MFU) including a complete hormone status (T3, T4, TSH, TG, TPOAb, TgAb, TRAb) and several ultrasound (US) evaluations using B-mode and color-coded Doppler imaging. The US evaluations contained measurement of volume, US Doppler, US echogenicity and US elastography. Additionally, applied energy (kJ), power output (W), number of shots (N) and total treatment time (s) were recorded in every case. RESULTS: Monopolar RFA resulted in a significant (p < 0.05) average thyroid volume reduction of Ø 18 ± 77 ml (25.1 ± 103%) and a nodule volume reduction of Ø 10.6 ± 22 ml (60.3 ± 62%). Bipolar RFA resulted in a significant (p < 0.05) average thyroid volume reduction of Ø 21.2 ± 54 ml (43.2 ± 84%) and a nodule volume reduction of Ø 13.8 ± 33 ml (70.8 ± 46%). Both groups showed equal results concerning volume reduction (p > 0.05). Monopolar RFA did not lead to any significant changes concerning the US scores, whereas bipolar RFA led to a significant (p < 0.05) reduction in US Doppler and nodular blood flow. No significant difference between both groups could be found concerning applied energy, treatment time, power output and number of shots (p > 0.05). CONCLUSION: Bipolar RFA did not show any disadvantages in comparison with monopolar RFA in the treatment of benign thyroid nodules. It shows better performance in terms of volume reduction and is superior when it comes to feasibility and patient discomfort. The recent study confirms the good ex vivo results for bipolar RFA.
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Ablación por Catéter/métodos , Nódulo Tiroideo/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Animales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Nódulo Tiroideo/diagnóstico por imagen , UltrasonografíaRESUMEN
INTRODUCTION: Right-sided Bochdalek hernia (BH) is a rare developmental defect in the posterolateral diaphragm, allowing herniation of abdominal contents into the thorax. To date only 44 reported cases of right-sided BH have been surgically managed in adults in literature. We report one additional case of right-sided BH with loss of Domain. "Loss of domain" (LOD) is a term used commonly in the hernia literature to describe the distribution of abdominal content between the hernia and residual abdominopelvic cavity. After repairing hernias with significant LOD, serious physiological complications can arise. METHODS: PubMed and Cochrane bibliographical databases were searched (last search: February 2022) for studies concerning BH. CASE PRESENTATION: We report the case of a 50-year-old woman whose right-sided diaphragmatic hernia strangulated loops of small bowel and who was thus treated via urgent laparoscopy. After reduction of the intrathoracic contents we were unable to primarily close the midline fascia.We performed a staged abdominal wall reconstruction as the chronicity of the hernia led to loss of intra-abdominal domain. DISCUSSION: Bochdalek hernia (BH) is the most common type of congenital diaphragmatic hernia and is usually leftsided. It typically presents in neonates and diagnosis in adults is a rarity. Various surgical repair options include open surgery, laparoscopic repair, thoracoscopic approach and robotic transthoracic approaches. CONCLUSION: BH should be managed timely regardless of its symptoms to avoid future complications. The closure of the defect can be done by different methods. When, after diaphragmatic hernia repair, it is suspected that the herniated viscera have lost their domain, it is preferable to use a Temporary Abdominal Closure to prevent compartment syndrome. KEY WORDS: Bochdalek hernia with loss of Domain, Bochdalek hernia in adults, Non traumatic Bochdalek hernia, Right-sided diaphragmatic hernia.
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Hernias Diafragmáticas Congénitas , Laparoscopía , Femenino , Recién Nacido , Humanos , Adulto , Persona de Mediana Edad , Hernias Diafragmáticas Congénitas/complicaciones , Hernias Diafragmáticas Congénitas/cirugía , Abdomen/cirugía , Intestino Delgado/cirugía , HerniorrafiaRESUMEN
The three-term conjugate gradient (CG) algorithms are among the efficient variants of CG algorithms for solving optimization models. This is due to their simplicity and low memory requirements. On the other hand, the regression model is one of the statistical relationship models whose solution is obtained using one of the least square methods including the CG-like method. In this paper, we present a modification of a three-term conjugate gradient method for unconstrained optimization models and further establish the global convergence under inexact line search. The proposed method was extended to formulate a regression model for the novel coronavirus (COVID-19). The study considers the globally infected cases from January to October 2020 in parameterizing the model. Preliminary results have shown that the proposed method is promising and produces efficient regression model for COVID-19 pandemic. Also, the method was extended to solve a motion control problem involving a two-joint planar robot.
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INTRODUCTION: Inguinal hernia is one of the most common surgical problems, often posing technical challenges even to expert surgeons. Amyand's hernia (AH) is an inguinal hernia whose sac contains the vermiform appendix. Primary appendiceal neoplasms are rare. We report the case of an appendiceal adenocarcinoma within an Amyand's hernia, presenting as an incarcerated right inguinal hernia. PRESENTATION OF CASE: A 87-year-old male presented in the emergency department due to a persistent right inguinal pain. Clinical examination revealed a tender right groin mass. Under the diagnosis of an right inguinal hernia, an operation was taken. Intraoperatively, an inflamed appendix and a part of the cecum were found in the hernia sac. The operation was completed with an ileocecal resection and a modified Bassini hernia repair. Histological examination revealed a adenocarcinoma of the appendix. DISCUSSION: Amyand's hernia is an inguinal hernia that contains vermiform appendix in its sac. It consists 1% of all inguinal hernias while appendicitis in an Amyand's hernia accounts for 0.1% of all appendicitis cases. Adenocarcinomas of the appendix are even rarer, accounting for 0.2% to 0.5% of all intestinal malignancies, and 4%-6% of primary appendiceal neoplasms. Diagnosis is usually established intraoperatively. CONCLUSION: A malignancy of the appendix should always be in the differential diagnosis of a right inguinal mass, in order to provide optimum surgical treatment.
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OBJECTIVE: To evaluate if internally cooled microwave ablation (cMWA) is a safe and effective method for treatment of benign and malign thyroid nodules. METHODS: 9 patients with 11 symptomatic cold benign thyroid nodules and 1 recurrent thyroid carcinoma ranging in volume from 9.1 to 197ml (mean size 52±â57ml) were treated with cMWA. The mean age of the patients was 59 years. Pain during the treatment was measured on a 10-point scale. Side effects revealed by ultrasound or patients' complaints were documented. Periablative efficacy was measured 24h after cMWA as change (Δ) in serum thyreoglobulin (Tg). Nodule elasticity was measured on a 4-point scale, blood circulation and echogenicity on a 3-point scale. RESULTS: All patients tolerated cMWA well. Median pain intensity averaged 2.1±0.8 (range: 1-3). Postablative hematoma was observed in all cases. In no cases ablation led to hoarseness, superficial burns, nodule ruptures, vagal reactions or dysphagia. cMWA lead to a significant decrease of blood circulation, nodule echogenicity and a significant increase of elasticity (Δâ=â1.1â±â0.33; 0.8â±â0.4 and 1.1â±â0.6 points)(p<0.05). An average increase of 4495ng/ml Tg was measured (p<0.05). CONCLUSIONS: cMWA is an effective and secure method for treatment of thyroid nodules.