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Key Clinical Message: If you encounter an unexplained case of bone marrow edema in a young patient, consider the possibility of osteoid osteoma (OO). Even in the presence of a nidus near vital structures, RFA can safely be used to treat OO. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Adenoid cystic carcinoma (ACC) is an uncommon malignancy of head and neck. Although the cornerstone of treatment is surgery, concurrent chemoradiotherapy (CRT) might be used as an effective treatment for unresectable tumors. Herein we report a case of massive ACC of base of tongue with durable complete response to definitive CRT. Adenoid cystic carcinoma (ACC) is a rare tumor accounting for 1% of all head and neck cancers. The best treatment option is complete surgical resection with or without adjuvant radiotherapy. When surgical resection is not feasible, definitive radiotherapy with or without concurrent chemotherapy can be considered. Herein we report a non‐smoker 72‐year‐old woman presented with throat discomfort and sensation of a lump. Evaluation revealed an unresectable adenoid cystic carcinoma of the base of tongue in whom complete clinical response was achieved after definitive concurrent chemoradiation. Although the cornerstone of treatment is complete surgical resection, this case report indicates that concurrent chemoradiotherapy might result in complete clinical response and could be used as a definitive treatment in selected ACC tumors. [ABSTRACT FROM AUTHOR]

The present study investigates vibrational behavior of a porous conical hollow rotor. Inner and outer rotor surface, sensor, and actuator strips made of piezoceramic are modeled and positioned, which are symmetrically distributed in the circumferential direction. Kinetic and potential energies were computed considering the effects of Coriolis and centrifugal force. Modeling of the system has been carried out assuming classical theory and using Lagrange approach for simple-supported boundary conditions. Also, the relations of piezoceramic and three types of porosity attend in equilibrium equations. The discretization of kinetic and potential energies using displacement field which is defined as double mixed series based on independent mode shape and time function leads to obtaining the equations in form of ordinary differential. To calculate the natural frequencies, the equations were converted to a special form of state space model. The correctness of the study is examined by comparing it with similar study results. The most consequential parameters affecting the forward and backward natural frequency, such as type and porosity coefficient, size, number, and thickness of piezoceramic, and the rotor angular velocity, are researched. The results demonstrate that the effect of porosity coefficient in various longitudinal modes on natural frequency is different. [ABSTRACT FROM AUTHOR]

Irrigation and crop management practices play a crucial role in ecology and agrohydrology and can have significant environmental and socio-economic impacts. The important decision factors include soil moisture and water salinity, particularly in arid and semi-arid regions. In this study, the effects of these two factors on maize are quantitatively measured. To collect data, design of experiments is utilized at a greenhouse in a research center. The dataset consists of eighteen variables, including sixteen qualitative, quantitative, and morphological maize characteristics, as well as two decision variables, i.e., water depletion and salinity. This endeavor aims to promote the use of multi-objective decision-making techniques in the water management context to improve agricultural practices in regions facing water scarcity. To ensure appropriate data analysis, besides data visualization, multivariate and repeated measures analysis of variance are employed. Subsequently, a repeated measures model is used to fit statistical models and construct the corresponding responses. Furthermore, to determine the optimal levels of soil moisture and water salinity, which are often in conflict with each other, the problem is approached within a multi-objective framework. The weighted p-norm method is employed to incorporate management priorities in the decision-making process and facilitate tradeoffs between these two factors. Policy implications based on the findings are provided, offering valuable insights for improving irrigation and crop management practices. Detailed guidelines are provided on how to effectively analyze a problem, construct a model, and verify its assumptions. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) is a non-invasive highly sensitive tool for diagnosing chondromalacia patellae in the early stages. Many studies have evaluated patellar and trochlear morphology with different radiologic indices. We aimed to assess the discriminative power of tibial, patellar, and femoral indices in MRI for chondromalacia patellae.

This investigation analyzes the effects of internal static fluid on the free vibrational behavior of joined shells made of carbon nanotube (CNT) fiber‐reinforced composite. Various types of functionally graded CNTs composite with temperature dependence are considered. Classic shell theory and Love's assumptions combined with Hamilton's principle are used to obtain motion equations. Bernoulli equation, velocity potential, and impermeability condition are employed to the coupling effects of fluid pressure with motion equations of shells. Continuity conditions in the joint point of conical and cylindrical sections are supposed to couple equations of two parts. The generalized differential quadrature (GDQ) method is employed to solve equations for various boundary conditions. Experimental modal tests on a sample made by the 3-D printer and prior others' research are used to validate the accuracy of results. Consequently, parametric studies are expressed, such as longitudinal and circumferential mode numbers, semi-vertex angle, distributions of CNTs, CNTs fraction volumes, fluid density, shell thickness, and operating temperature. According to the results, although fluid decreases the frequency generally, the process of changing frequency in terms of other parameters is similar. [ABSTRACT FROM AUTHOR]

This research analyzes the influence of temperature changes on the vibration of single-walled carbon nanotubes (SW-CNTs) composite joined conical-cylindrical shells. The governing dynamic equations of temperature-dependent CNTs with initial thermomechanical stresses are established using the Love shell assumptions and classical shell theory. The initial thermomechanical stresses are derived from the linear membrane approach method. Two possibilities are assumed for the calculation of temperature change: a uniform temperature distribution and steady-state heat transfer by conduction through the thickness of the shell. The initial thermomechanical stresses are determined using the linear membrane approach. The generalized differential quadrature (GDQ) method is used to solve the equations after combining it with continuity conditions between the conical part and the cylindrical part and various boundary conditions. After validating the natural frequency and the different types of temperature distribution with the studies of other researchers, the effects of semi vortex of the cone, the volume fraction, and the type of distribution on the temperature rise are given as the results. The type of temperature distribution has the greatest influence among the parameters. [ABSTRACT FROM AUTHOR]

This paper presents an improved switched‐inductor quasi‐Z‐source inverter with a higher boost factor than similar inverters, which integrates a switched‐capacitor and a three‐winding switched‐coupled inductor into a conventional quasi Z‐source inverter (q‐ZSI). The proposed inverter is called a switched‐capacitor trans quasi Z‐source inverter (SCT‐q‐ZSI). In this topology, the input current is continuous, and a high voltage gain is reachable with lowduty cycles (D). In this structure, capacitors are used instead of the side diodes of the switched‐inductor quasi Z‐source inverter. The proposed converter has a low inrush current at the startup which might damage the converter components. The performance of the proposed inverter is investigated at different operating modes and the voltage and current equations of all elements are calculated. The analysis, derivation of boost factor, capacitor voltages, and components, of the proposed inverter, are carried out and are compared with similar inverters. Finally, analytical, simulation, and experimental results are also presented to validate its advantages. [ABSTRACT FROM AUTHOR]

Background: Internal mammary lymph nodes (IMNs) are a potential site of metastasis for breast cancer. Targeting IMNs as part of a comprehensive regional nodal irradiation comes at the cost of higher unwanted doses to critical nearby organs at risk. Thus, the efficacy and safety of different radiotherapy techniques for the coverage of this area remain elusive. Objectives: We present a dosimetric comparison between partially wide tangents (PWT) and direct photon/electron (P/E) portals in terms of target volume coverage and normal tissue sparing. Methods: Patients with left-sided breast cancer, who were referred to our clinic for post-lumpectomy or post-mastectomy radio-therapy, underwent computed tomography (CT) simulation. The left breast and IMNs, heart, lung, right breast, and esophagus were contoured. Dosimetric comparisons were based on dose-volume histograms (DVHs) generated for all of the aforementioned organs. A subgroup analysis was also performed based on patients' type of surgical treatment. Results: A total of 30 patients (10 with breast conserving surgery and 20 with modified radical mastectomy) were included. The P/E plan provided a higher coverage of the left breast (P-value of CTV V105%: < 0.001) and IMNs with a P-value of 0.087 regarding the mean dose received by IMNs, and also less volume of the heart (P-value of Heart V30Gy: 0.021), and lungs (P-value of Lung V20Gy: 0.003) were irradiated. However, these advantages came at the cost of a higher dose to the esophagus and right breast and more hotspots compared to the PWT technique. Conclusions: The P/E technique had advantages regarding target volume coverage and toxicity regardless of the type of surgery. Based on the results of this study, overall, the P/E portal is superior to the PWT for radiotherapy of breast cancer with internal mammary node inclusion. However, the appropriate treatment plan should be decided on a case-by-case basis. [ABSTRACT FROM AUTHOR]

Cholangiocarcinoma, malignant tumor of epithelial cells of bile ducts has poor overall survival and prognosis. We report a case of non-resectable cholangiocarcinoma with a 57-month survival after incomplete R2 surgical margin resection of the tumor. A 52-year old man with generalized itching, jaundice, brownish urine, mild abdominal pain and weight loss of 8 kg in last two months presented. Imaging and surgical workups showed hilar cholangiocarcinoma (Klatskin tumor). Along with incomplete R2 margin resection we performed stent embedding and post-operative adjuvant chemotherapy. Based on current literature data there is no superiority of adjuvant chemotherapy after complete R0 resection compared to incomplete R2 resection. However, it seems that partial resection along with stent embedding and applied adjuvant chemotherapy in cases of locally advanced non-resectable cholangiocarcinoma may increase survival rate.