Bar-grid oscillators

Grid oscillators are an attractive way of obtaining high power levels from the solid-state devices, since potentially the output powers of thousands of individual devices can be combined. The active devices do not require an external locking signal, and the power combining is done in free space. Thirty-six transistors were mounted on parallel brass bars, which provide a stable bias and have a low thermal resistance. The output power degraded gradually when the devices failed. The grid gave an effective radiated power of 3 W at 3 GHz. The directivity was 11.3 dB, and the DC-to-RF efficiency was 22%. Modulation capabilities of the grid were demonstrated. An equivalent circuit model for the grid is derived, and comparison with experimental results is shown

Automated Segmentation and Recurrence Risk Prediction of Surgically Resected Lung Tumors with Adaptive Convolutional Neural Networks

Lung cancer is the leading cause of cancer related mortality by a significant margin. While new technologies, such as image segmentation, have been paramount to improved detection and earlier diagnoses, there are still significant challenges in treating the disease. In particular, despite an increased number of curative resections, many postoperative patients still develop recurrent lesions. Consequently, there is a significant need for prognostic tools that can more accurately predict a patient's risk for recurrence. In this paper, we explore the use of convolutional neural networks (CNNs) for the segmentation and recurrence risk prediction of lung tumors that are present in preoperative computed tomography (CT) images. First, expanding upon recent progress in medical image segmentation, a residual U-Net is used to localize and characterize each nodule. Then, the identified tumors are passed to a second CNN for recurrence risk prediction. The system's final results are produced with a random forest classifier that synthesizes the predictions of the second network with clinical attributes. The segmentation stage uses the LIDC-IDRI dataset and achieves a dice score of 70.3%. The recurrence risk stage uses the NLST dataset from the National Cancer institute and achieves an AUC of 73.0%. Our proposed framework demonstrates that first, automated nodule segmentation methods can generalize to enable pipelines for a wide range of multitask systems and second, that deep learning and image processing have the potential to improve current prognostic tools. To the best of our knowledge, it is the first fully automated segmentation and recurrence risk prediction system.Comment: 9 pages, 5 figure

Identifying The Health Needs In Rural Appalachian Ohio: Outcomes Of A Rural Community-Academic Partnership

To identify health issues in two rural counties, a needs assessment was developed by health officials and researchers. Focus groups (n = 32) and interviews (n = 8) were conducted among community leaders and a modified BRFFS survey was completed by 399 community members. Results indicated the health of the participants was influenced by: 1) rural Appalachian culture, 2) geography and access to health care, and 3) lack of access/knowledge about preventive health behaviors. These issues likely contributed to 30% obesity prevalence among the sample, which was prioritized as the main health issue for both counties.

Endotelialne komórki progenitorowe (EPCs) w terapii

Stem progenitor cells serve as a functional reserve and may differentiate into mature cells with a different phenotype. Partially differentiated endothelial progenitor cells (EPCs) are characterized by the expression of surface molecules such as endoglin (CD105), vWF, PECAM-1/CD31, VE-cadherin, CD146, CD62E, CD51/61, CD106, CD41a, CD41b, CD34 and AC133, growth factor receptors (e.g. Flt-1, KDR and Tie-1) and others. They may also express the functional capabilities of endothelial cells in the course of their differentiation (e.g. incorporation of modified LDL). Animal studies have confirmed the proangiogenic activity of labelled human (bone marrow, umbilical cord and peripheral blood) as well as animal EPCs in the experimental models of myocardial, peripheral and cerebral ischaemia. The goal of these studies has been to improve the vascularisation and functional activity of the target organs. The first clinical studies in peripheral and coronary artery disease revealed the clinical efficacy of human bone marrow-derived mononuclear fraction in diminishing the adverse effects of peripheral and myocardial ischaemia. No significant side-effects of the EPC application were observed, but further studies are required to confirm the long-term safety and efficacy of this method as well as to assess its possible hazards.Komórki progenitorowe stanowią tkankową rezerwę czynnościową, która "na żądanie" może dojrzewać do komórek docelowych. Komórki progenitorowe dla śródbłonka charakteryzuje ekspresja markerów powierzchniowych, takich jak np. endoglina (CD105), vWF, PECAM-1/CD31, VE-kadheryna, CD146, CD62E, CD51/61, CD106, CD41a, CD41b, CD34, AC133, receptory czynników wzrostu (np. Flt-1, KDR, Tie-1) i inne. W toku różnicowania śródbłonkowe komórki progenitorowe mogą prezentować cechy czynnościowe dojrzałych komórek śródbłonka (np. wchłanianie zmodyfikowanych LDL). Badania przeprowadzone na zwierzętach dowiodły proangiogennej skuteczności stosowania znakowanych ludzkich i zwierzęcych komórek progenitorowych w modelach doświadczalnych niedokrwienia serca, kończyn dolnych i mózgu. Podstawowym kryterium oceny eksperymentów była poprawa unaczynienia i funkcji narządu docelowego. Nie obserwowano istotnych objawów ubocznych, chociaż trzeba brać pod uwagę możliwe zagrożenia. Badania kliniczne dotyczące miażdżycy naczyń obwodowych i choroby niedokrwiennej serca wykazały skuteczność kliniczną subfrakcji ludzkich komórek mononuklearnych szpiku i krwi obwodowej w zmniejszaniu niekorzystnych następstw niedokrwienia obwodowego i mięśnia sercowego. Konieczne są jednak dalsze badania potwierdzające skuteczność i bezpieczeństwo tej metody

Repression of nodal expression by maternal B1-type SOXs regulates germ layer formation in Xenopus and zebrafish

AbstractB1-type SOXs (SOXs 1, 2, and 3) are the most evolutionarily conserved subgroup of the SOX transcription factor family. To study their maternal functions, we used the affinity-purified antibody antiSOX3c, which inhibits the binding of Xenopus SOX3 to target DNA sequences [Development. 130(2003)5609]. The antibody also cross-reacts with zebrafish embryos. When injected into fertilized Xenopus or zebrafish eggs, antiSOX3c caused a profound gastrulation defect; this defect could be rescued by the injection of RNA encoding SOX3ΔC-EnR, a SOX3-engrailed repression domain chimera. In antiSOX3c-injected Xenopus embryos, normal animal–vegetal patterning of mesodermal and endodermal markers was disrupted, expression domains were shifted toward the animal pole, and the levels of the endodermal markers SOX17 and endodermin increased. In Xenopus, SOX3 acts as a negative regulator of Xnr5, which encodes a nodal-related TGFβ-family protein. Two nodal-related proteins are expressed in the early zebrafish embryo, squint and cyclops; antiSOX3c-injection leads to an increase in the level of cyclops expression. In both Xenopus and zebrafish, the antiSOX3c phenotype was rescued by the injection of RNA encoding the nodal inhibitor Cerberus-short (CerS). In Xenopus, antiSOX3c's effects on endodermin expression were suppressed by injection of RNA encoding a dominant negative version of Mixer or a morpholino against SOX17α2, both of which act downstream of nodal signaling in the endoderm specification pathway. Based on these data, it appears that maternal B1-type SOX functions together with the VegT/β-catenin system to regulate nodal expression and to establish the normal pattern of germ layer formation in Xenopus. A mechanistically conserved system appears to act in a similar manner in the zebrafish

The effect of antioxidant status on overall survival in renal cell carcinoma

Introduction The oxidative stress contributes to all three phases of carcinogenesis and represents a concomitant condition in renal cell carcinoma (RCC). RCC is the most common type of neoplasm of the kidney, and despite numerous studies the set of predictive and prognostic markers of survival are still unknown. The aim of our study was to examine the relation between antioxidant (AO) status and overall survival (OS) in RCC patients. Material and methods Our study included 95 patients with RCC, who underwent radical nephrectomy. We analysed the prognostic role of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase, glutathione reductase, glutathione, and malondialde-hyde) and other clinicopathological factors (size, grade, stage, and histological subtype) on the OS of RCC patients. Results The 5-year OS was 54.6%. The survival analysis related to AO parameters showed no significant difference in survival of RCC patients. The concentration of malondialdehyde, an indicator of lipid peroxidation, also had no significant effect on the survival rate of RCC pa-tients. Univariate and multivariate analysis confirmed the significance of clinicopathological parameters (size, p < 0.001; Fuhrman grade, p = 0.001, and stage, p < 0.001) for patients’ survival. Conclusions In our cohort of patients, different antioxidant parameters were not found to be predictors for OS of patients with RCC, who underwent radical nephrectomy

Malignant hepatic epithelioid hemangioendothelioma: case of a rare liver tumor mimicking metastasis

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