1,351 research outputs found
Inverted Martian Craters in Lineated Glacial Valleys, Ismenius Lacus Region, Mars
We studied small, uniquely-shaped craters found on the surface of lineated terrain in the Ismenius Lacus region of Mars. By utilizing MOC and THEMIS satellite images, we located terrain including lineations (viscous flow features), smoothing of topography, and morphologic features such as polygons and gullies, which appear to be strong evidence of preexisting ice deposits
Fifty tumor necrosis factor-based isolated limb perfusions for limb salvage in patients older than 75 years with limb-threatening soft tissue sarcomas and other extremity tumors
BACKGROUND: Isolated limb perfusion (ILP) with tumor necrosis factor (TNF)
and melphalan is highly effective in treating limb-threatening soft tissue
sarcoma (STS) and other bulky tumors. Because of fear of TNF-associated
toxicity, ILP with TNF is not offered to older patients in some cancer
centers, although especially in older patients, every attempt to avoid an
amputation that may end their independence must be considered. METHODS:
Out of 306 TNF-based ILPs, 50 ILPs were performed for limb salvage in 43
patients >75 years old (range, 75-91 years): 29 STS and 14 melanoma
patients. RESULTS: In the STS patients, a response rate of 76% and a
limb-salvage rate of 76% were achieved; in the melanoma patients, a 100%
response rate and a 93% limb-salvage rate were achieved. Local toxicity
was mild. The three postoperative deaths that occurred in the total series
of 306 TNF-based ILPs in Rotterdam (75 years
old after leakage-free perfusions and were not related to TNF but to
extremely high-risk profiles in these three patients. CONCLUSIONS: Older
patients should not be withheld a TNF-based ILP for limb salvage, because
the procedure is safe and highly effective in these patients
Integrated Phase Array Antenna/Solar Cell System for Flexible Access Communication (IA/SAC)
This paper describes recent efforts to integrate advanced solar cells with printed planar antennas. Several previous attempts have been reported in the literature, but this effort is unique in several ways. It uses Gallium Arsenide (GaAs) multi-junction solar cell technology. The solar cells and antennas will be integrated onto a common GaAs substrate. When fully implemented, IA/SAC will be capable of dynamic beam steering. In addition, this program targets the X-band (8 - 12 GHz) and higher frequencies, as compared to the 2.2 - 2.9 GHz arrays targeted by other organizations. These higher operating frequencies enable a greater bandwidth and thus higher data transfer rates. The first phase of the effort involves the development of 2 x 2 cm GaAs Monolithically Integrated Modules (MIM) with integrated patch antennas on the opposite side of the substrate. Subsequent work will involve the design and development of devices having the GaAs MIMs and the antennas on the same side of the substrate. Results from the phase one efforts will be presented
Adequate symptom relief justifies hepatic resection for benign disease
BACKGROUND: The purpose of this study was to evaluate the long-term results of partial liver resection for benign liver lesions. METHODS: All patients operated on for benign liver lesions from 1991 to 2002 were included. Information was retrieved from medical records, the hospital registration system and by a telephonic questionnaire. RESULTS: Twenty-eight patients with a median age of 41 years (17–71) were operated on (M/F ratio 5/23). The diagnosis was haemangioma in 8 patients, FNH in 6, HCA in 13 and angiomyolipoma in 1. Eight patients were known to have relevant co-morbidity. Median operating time was 207 minutes (45–360). The morbidity rate was 25% and no postoperative mortality was observed. Twenty-two patients (79%) had symptoms (mainly abdominal pain) prior to surgery. Twenty-five patients were reached for a questionnaire. The median follow up was 55 months (4–150). In 89% of patients preoperative symptoms had decreased or disappeared after surgery. Four patients developed late complications. CONCLUSION: Long-term follow up after liver surgery for benign liver lesions shows considerable symptom relief and patient satisfaction. In addition to a correct indication these results justify major surgery with associated morbidity and mortality
Risk Factors for Positive Deep Pelvic Nodal Involvement in Patients with Palpable Groin Melanoma Metastases: Can the Extent of Surgery be Safely Minimized?: A Retrospective, Multicenter Cohort Study
Background: Patients with palpable melanoma groin metastases have a poor prognosis. There is debate whether a combined superficial and deep groin dissection (CGD) is necessary or if superficial groin dissection (SGD) alone is sufficient. Aim: The aim of this study was to analyze risk factors for deep pelvic nodal involvement in a retrospective, multicenter cohort of palpable groin melanoma metastases. This could aid in the development of an algorithm for selective surgery in the future. Methods: This study related to 209 therapeutic CGDs from four tertiary centers in The Netherlands (1992–2013), selected based on complete preoperative imaging and pathology reports. Analyzed risk factors included baseline and primary tumor characteristics, total and positive number of inguinal nodes, inguinal lymph node ratio (LNR) and positive deep pelvic nodes on imaging (computed tomography [CT] ± positron emission tomography [PET], or PET − low-dose CT). Results: Median age was 57 years, 54 % of patients were female, and median follow-up was 21 months (interquartile range [IQR] 11–46 months). Median Breslow thickness was 2.10 mm (IQR 1.
Identification of receptor-type protein tyrosine phosphatase μ as a new marker for osteocytes
Osteocytes are the predominant cells in bone, where they form a cellular network and display important functions in bone homeostasis, phosphate metabolism and mechanical transduction. Several proteins strongly expressed by osteocytes are involved in these processes, e.g., sclerostin, DMP-1, PHEX, FGF23 and MEPE, while others are upregulated during differentiation of osteoblasts into osteocytes, e.g., osteocalcin and E11. The receptor-type protein tyrosine phosphatase µ (RPTPμ) has been described to be expressed in cells which display a cellular network, e.g., endothelial and neuronal cells, and is implied in mechanotransduction. In a capillary outgrowth assay using metatarsals derived from RPTPμ-knock-out/LacZ knock-in mice, we observed that the capillary structures grown out of the metatarsals were stained blue, as expected. Surprisingly, cells within the metatarsal bone tissue were positive for LacZ activity as well, indicating that RPTPμ is also expressed by osteocytes. Subsequent histochemical analysis showed that within bone, RPTPμ is expressed exclusively in early-stage osteocytes. Analysis of bone marrow cell cultures revealed that osteocytes are present in the nodules and an enzymatic assay enabled the quantification of the amount of osteocytes. No apparent bone phenotype was observed when tibiae of RPTPμ-knock-out/LacZ knock-in mice were analyzed by μCT at several time points during aging, although a significant reduction in cortical bone was observed in RPTPμ-knock-out/LacZ knock-in mice at 20 weeks. Changes in trabecular bon
Small X-Band Oscillator Antennas
A small, segmented microstrip patch antenna integrated with an X-band feedback oscillator on a high-permittivity substrate has been built and tested. This oscillator antenna is a prototype for demonstrating the feasibility of such devices as compact, low-power-consumption building blocks of advanced, lightweight, phased antenna arrays that would generate steerable beams for communication and remotesensing applications
Image informatics strategies for deciphering neuronal network connectivity
Brain function relies on an intricate network of highly dynamic neuronal connections that rewires dramatically under the impulse of various external cues and pathological conditions. Among the neuronal structures that show morphologi- cal plasticity are neurites, synapses, dendritic spines and even nuclei. This structural remodelling is directly connected with functional changes such as intercellular com- munication and the associated calcium-bursting behaviour. In vitro cultured neu- ronal networks are valuable models for studying these morpho-functional changes. Owing to the automation and standardisation of both image acquisition and image analysis, it has become possible to extract statistically relevant readout from such networks. Here, we focus on the current state-of-the-art in image informatics that enables quantitative microscopic interrogation of neuronal networks. We describe the major correlates of neuronal connectivity and present workflows for analysing them. Finally, we provide an outlook on the challenges that remain to be addressed, and discuss how imaging algorithms can be extended beyond in vitro imaging studies
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