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Background and Aim: Pseudomyxoma peritonei (PMP) is an unusual condition with unique behaviour caused by a mucinous neoplasm, usually arising from the appendix. The aim of this study was to evaluate the prevalence of genomic alterations in clinical specimens of PMP using a targeted assay and correlate the findings with clinical, pathological and outcome data. Sequencing data from 223 patients were analysed. Results: The median follow‐up interval was 48 months. The primary neoplasm was appendiceal in 216 patients, ovarian in 4, urachal in 2 and renal in one. We confirmed common mutations in GNAS and KRAS (42% each) with significant co‐occurrence of variants in these genes. TP53 mutations were found in 8%. Other mutations were rare but included novel mutations in BAP1 and ERBB4. Of 17 patients with acellular peritoneal mucin, 6 (35%) were positive for DNA mutations. The non‐appendiceal cases generally showed a similar mutational landscape to the appendiceal lesions with GNAS and KRAS commonly mutated, although one urachal lesion showed multi‐hit TP53 mutation without variants in either GNAS or KRAS. Survival was significantly associated with the grade of the primary neoplasm, the grade of the peritoneal disease, the completeness of cytoreduction score and with mutation in either GNAS, KRAS or both. The hazard ratio (HR) associated with mutation in GNAS and/or KRAS was 1.87 (p = 0.004). Conclusions: Survival outcome was more closely associated with the grade of the peritoneal disease than with the grade of the primary neoplasm. Our findings support the developing concept that mutational analysis may provide prognostic information in patients with PMP. [ABSTRACT FROM AUTHOR]

A hypersurface M in R n or S n is said to be Dupin if along each curvature surface, the corresponding principal curvature is constant. A Dupin hypersurface is said to be proper Dupin if each principal curvature has constant multiplicity on M, i.e., the number of distinct principal curvatures is constant on M. The notions of Dupin and proper Dupin hypersurfaces in R n or S n can be generalized to the setting of Lie sphere geometry, and these properties are easily seen to be invariant under Lie sphere transformations. This makes Lie sphere geometry an effective setting for the study of Dupin hypersurfaces, and many classifications of proper Dupin hypersurfaces have been obtained up to Lie sphere transformations. In these notes, we give a detailed introduction to this method for studying Dupin hypersurfaces in R n or S n , including proofs of several fundamental results. We also give a survey of the results in the field that have been obtained using this approach. [ABSTRACT FROM AUTHOR]

Background: Epithelial appendiceal neoplasms are uncommon peritoneal malignancies causing a spectrum of disease including pseudomyxoma peritonei (PMP). The optimal management is cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC). Despite complete CRS (CCRS), recurrence develops in almost 45% of patients. No consensus exists for the optimal treatment of recurrent disease, with treatment strategies including repeat CRS, watch-and-wait, and palliative chemotherapy. This report aims to describe evolving management strategies for a large cohort with recurrence after CCRS. Methods: This retrospective study analyzed a prospective database of patients with recurrence after CCRS for appendiceal neoplasms from 1994 to 2017 who had long-term follow-up evaluation with tumor markers and computed tomography (CT). Results: Overall, 430 (37.6%) of 1145 PMP patients experienced recurrence at a median of 19 months. Of these 430 patients 145 (33.7%) underwent repeat CRS, 119 (27.7%) had a watch-and-wait approach, and 119 (27.7%) had palliative chemotherapy. The patients with recurrence had a median overall survival (OS) of 39 months, a 3-year survival of 74.6%, a 5-year survival of 57.4%, and a 10-year survival of 36.5%. In the multivariate analysis, the patients who had recurrence within 1 year after primary CRS (hazard ratio [HR], 3.55), symptoms at recurrence (HR, 3.08), a high grade of disease or adenocarcinoma pathology (HR, 2.94), signet ring cells (HR, 1.91), extraperitoneal metastatic disease (HR, 1.71), or male gender (HR, 1.61) had worse OS. The OS was longer for the patients who had repeat CRS (HR, 0.41). The patients who underwent repeat CCRS had a 3-year OS of 87.5%, a 5-year OS of 78.1%, and a 10-year OS of 67.9%. Conclusions: Dilemmas persist around the optimal management of patients with recurrence after CRS and HIPEC for appendiceal tumors. Selected patients benefit from repeat CRS, particularly those with favorable tumor biology and focal disease. [ABSTRACT FROM AUTHOR]

Aims: Patients with abdominal cancer requiring major surgical intervention are at high risk of venous thromboembolic events (VTE), particularly pulmonary emboli (PE). A proportion of patients with cancer can present with, or have had, major VTEs prior to definitive surgical treatment. Preoperative percutaneous inferior venal caval filters (IVCF) may reduce the risk of PE. The aim of this study was to assess the indications, complications, retrieval rates, and long‐term outcome of IVCFs in patients undergoing major abdominal surgery. Methods: This was a retrospective analysis of a prospective IVCF database between 2007 and 2018 of all patients with IVCF insertion prior to major abdominal surgery. The indications for an IVCF, procedural complications and surgical interventions were recorded. Results: Overall, 111 patients had IVCF insertion. IVCF placement failed in one patient with gross abdominal disease. Indications for an IVCF were: prior PE in 65/111 (59%) and major vein thrombus in 42 (38%). Overall, 26/111 (23%) had the IVCF removed at a median of 91 days. In two patients IVCF removal failed. At follow‐up of the 85 patients who had the IVCF left in situ, six developed filter‐related thrombus and 13 a deep vein thrombosis (DVT). Four patients had a PE with an indwelling IVCF. Conclusion: Preoperative IVCF may reduce perioperative PE in patients at high risk of thrombosis undergoing major abdominal surgery where early anticoagulation is contraindicated. Long‐term follow‐up of retained IVCF suggests that major problems are infrequent, though further thrombosis may occur and long‐term anticoagulation may be needed. [ABSTRACT FROM AUTHOR]

Future cosmic microwave background (CMB) experiments will deploy increasing numbers of superconducting detectors with requirements for increased sensitivity and reduced systematics. We report on the ongoing development of OMT-coupled CMB detectors at Argonne National Laboratory. Key areas of development include bolometers with dual Transition Edge Sensors (TES) for easier lab characterization, a hybrid SiN membrane fabrication process, a chemical vapor deposition (CVD) SiN dielectric process, and a new pixel design for improved compatibility with large scale fabrication. These developments enhance our ability to fabricate large-scale (150 mm diameter wafers) detector arrays with the performance necessary for future CMB experiments. [ABSTRACT FROM AUTHOR]

The South Pole Telescope SPT-3G camera utilizes Ti/Au transition edge sensors (TESs). A key requirement for these sensors is reproducibility and long-term stability of the superconducting (SC) transitions. Here, we discuss the impact of electrical contacts design and materials on the shape of the SC transitions. Using scanning electron microscope, atomic force microscope, and optical differential interference contrast microscopy, we observed the presence of unexpected defects of morphological nature on the titanium surface and their evolution in time in proximity to Nb contacts. We found direct correlation between the variations of the morphology and the SC transition shape. Experiments with different diffusion barriers between TES and Nb leads were performed to clarify the origin of this problem. We have demonstrated that the reproducibility of superconducting transitions can be significantly improved by preventing diffusion processes in the TES-leads contact areas. [ABSTRACT FROM AUTHOR]

Aim: The neutrophil-lymphocyte ratio (NLR) and other inflammation-based scores have been used as a prognostic tool to predict survival in solid tumours including pseudomyxoma peritonei (PMP). The aim was to evaluate the prognostic value of this marker and risk stratify PMP patients undergoing cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Methods: Retrospective analysis was conducted of a prospectively collected database of patients with PMP who underwent CRS and HIPEC between 1994 and 2015. The NLR was calculated by dividing the pre-operative neutrophil count by lymphocyte count. Predicted overall survival (OS) and disease-free interval (DFI) were calculated using a Kaplan-Meier survival model. Results: The study included 699 patients, stratified into four groups as defined by their NLR. Group A: 200 (28.6%) patients (NLR = 0.10-2.00), Group B: 160 (22.8%) patients (NLR = 2.10-2.78), Group C: 184 (26.3%) patients (NLR = 2.79-4.31) and Group D: 155 (22.2%) patients (NLR ≥ 4.32). The median follow-up for this cohort was 36 months. The predicted DFI was 132.2, 113.1, 84.4 and 47.9 months and the OS was 141.1, 117.6, 88.7 and 51.2 months for Groups A, B, C and D, respectively. As the NLR increases, there is a reduction in long-term survival. Conclusion: The pre-operative NLR is cost effective and has equivalent prognostic value to pre-operative tumour markers for patients with PMP treated with CRS and HIPEC. The NLR is a reliable tool that may have a role in predicting outcomes following CRS and HIPEC for patients with PMP of appendiceal origin. [ABSTRACT FROM AUTHOR]

Transition edge sensors (TES) offer some of the highest resolutions for solid-state X-ray spectrometers. We are developing TES detectors for use at hard X-ray synchrotron light sources for energy ranges up to 20 keV. Because TES resolving power scales inversely with the square root of heat capacity, it is important to have an absorber with both a small heat capacity and a large X-ray stopping power. We are developing electroplated bismuth (Bi) absorbers to meet these criteria. Although Bi has a smaller X-ray absorption at 20 keV than gold, the specific heat is up to two orders of magnitude smaller, allowing for much larger collection area (up to 1 mm ^2) without significantly increasing the total device specific heat. However, due to its low thermal conductivity, Bi absorbers may have longer thermalization times. Also, some evaporated Bi absorbers may produce spectra with low-energy tails that will hinder X-ray line shape analysis and increase minimum detectability limits of trace metals for X-ray fluorescence microscopy. We examine the impact of plating current density, agitation, film thickness, and seed layer thickness on the grain size, residual resistance ratio, and uniformity of Bi absorbers. Additionally, we discuss processing considerations important for successful electroplating. [ABSTRACT FROM AUTHOR]

We are developing room temperature electronics based upon the ROACH platform to readout microwave multiplexed X-ray TES. ROACH is an open-source hardware and software platform featuring a large Xilinx Field Programmable Gate Array (FPGA), Power PC processor, several 10 GB Ethernet SFP+ interfaces, and a collection of daughter boards for analog signal generation and acquisition. The combination of a ROACH board, ADC/DAC conversion daughter boards, and hardware for RF mixing allows for the generation and capture of multiple RF tones for reading out microwave multiplexed X-ray TES microcalorimeters. The FPGA is used to generate multiple tones in base band, from 10 MHz to 250 MHz, which are subsequently mixed to RF in the multiple GHz range and sent through the microwave multiplexer. The tones are generated in the FPGA by storing a large lookup table in Quad Data Rate SRAM modules and playing out the waveform to a DAC board. Once the signal has been modulated to RF, passed through the microwave multiplexer, and has been modulated back to base band, the signal is digitized by an ADC board. The tones are modulated to 0 Hz by using a FPGA circuit consisting of a polyphase filter bank, several Xilinx FFT blocks, Xilinx CORDIC blocks (for converting to magnitude and phase), and special phase accumulator circuit for mixing to exactly 0 Hz. Upwards of 256 channels can be simultaneously captured and written into a bank of 256 First-In-First-Out (FIFO) memories, with each FIFO corresponding to a channel. Individual channel data can be further processed in the FPGA before being streamed through a 10 GB Ethernet fiber-optic interface to a Linux system. The Linux system runs software written in Python and QT C++ for controlling the ROACH system, capturing data, and processing data. [ABSTRACT FROM PUBLISHER]

Increasing the operating frequency of SIS receivers requires a shift from Nb/Al A1Ox /Nb junctions to new material systems. Two major limiting factors of higher frequency operation are the increase in subgap leakage that occurs in A1Ox barriers as current densities approach and exceed 10 kA/cm2 and the increased loss in Nb electrodes above ∼700 GHz. A promising alternative structure is the hybrid Nb/Al-AIN/NbTiN junction. Realization of these devices has been difficult due to the challenge of fabricating devices with repeatable current densities and electrical characteristics. We present on the fabrication and dc testing of Nb/AIN/NbTiN junctions. The AIN barrier is formed using our inductively coupled plasma (ICP) technique which allows for independent control of both ion energy and current density. This improved control enables the repeatable synthesis of high quality and high Jc barriers. Nb and NbTiN electrodes are deposited by unbalanced dc magnetron. A new fabrication process was developed to enable fabrication of junctions with area as small as 0.28 μm2. The relationship between barrier thickness and plasma conditions is determined by in-situ discrete ellipsometry. Ellipsometry results were verified by comparison with measured current-voltage characteristics. 1(V) curves for a range of junction sizes are presented. Plans for in-situ Faraday monitoring of the energy and current density of the ICP nitridation plasma will also be discussed. [ABSTRACT FROM AUTHOR]

We have fabricated high quality M1/barrier/M2/Au superconducting insulating superconducting (SIS) junctions with Au over-layers using a new multilayer pentalevel resist process. The wafer/NFR/polyimide/SiO2/Cr/imaging resist pentalevel structure enables precise definition of submicron junction features in a self-aligned insulation process. This scheme, unlike our previous multilevel resists, affords precise definition of the final Nb layer from an initial etch of a thinner top Cr layer. The Cr layer, defined with chlorine based RIE, serves as an excellent mask for the subsequent fluorine and oxygen based RIE etches of the remaining pentalevel stack and M2 electrode. We present a detailed description of the pentalevel process and electrical characteristics of NbTiN SIS junctions fabricated with this new technique. [ABSTRACT FROM AUTHOR]

High-energy-gap superconductors with low resistive loss and high-current-density tunnel barriers are important to increasing the operating range of THz electronics. This paper describes the development of superconducting NbTiN thin films and A1N tunnel barriers using ellipsometry analysis. NbTiN thin films were deposited by reactive DC unbalanced magnetron sputtering of NbTi in argon and nitrogen plasma onto a water-cooled, grounded substrate. The effects of total sputtering pressure, gas ratio, working distance, and voltage elevation were examined. A1N tunnel barriers were formed from DC magnetron sputtered thin films with the unique use of an ICP plasma source. The results of this ellipsometry analysis, using both discrete in-situ and spectroscopic ex-situ ellipsometers, are discussed. [ABSTRACT FROM AUTHOR]

We have implanted 30 keV gallium ions into niobium films 100 Å thick using a focused-ion beam (FIB). The nature of the FIB tool allows the irradiation of a specific, controllable, area of the substrate, from hundreds of square microns down to an arbitrary, user-defined pattern defined by a 70 Å stencil. A sacrificial layer of gold covering the niobium controls the range of the incident gallium ions and prevents the niobium film from sputtering away under bombardment. This article examines the behavior of these films phenomenologically, including information about the changes in transition temperature and resistance of the implanted samples. Also a curious unexplained feature of the resistive transition at implant doses below about 3 x 1019 cm-3 will be presented and discussed. [ABSTRACT FROM AUTHOR]

PURPOSE:. Most series report lymph node involvement as the main predictor for local recurrence. The principal lymphatic drainage of the rectum is to nodes in the mesorectum and then nodes along the superior rectal and inferior mesenteric arteries. If total mesorectal excision provides adequate block dissection of the lymphatics of the rectum, good local control with low rates of local recurrence should be achieved even in node-positive disease. METHODS:. Prospective data on all rectal cancers have been collected since 1978; 170 patients with Dukes C rectal cancer have undergone anterior resection and total mesorectal excision. We did not perform any internal iliac node dissections. Follow-up data were analyzed for local recurrence and distant recurrence. RESULTS:. The local recurrence rate was 2 percent for Dukes A cases, 4 percent for Dukes B, and 7.5 percent for Dukes C (P = 0.0127). The systemic recurrence rate was 8 percent for Dukes A, 18 percent for Dukes B, and 37 percent for Dukes C (P = 0.0001). CONCLUSIONS:. If surgical priority is given to the difficult task of excision of the whole mesorectum, anterior resection with total mesorectal excision in node-positive rectal cancer, local recurrence rates of < 10 percent can be achieved. [ABSTRACT FROM AUTHOR]

Using the method of moving frames, we prove that any irreducible Dupin hypersurface in S5 with four distinct principal curvatures and constant Lie curvature is equivalent by Lie sphere transformation to an isoparametric hypersurface in S5. [ABSTRACT FROM AUTHOR]

Using the method of moving frames, we prove that any locally irreducible Dupin hypersurface in S n with three distinct principal curvatures is equivalent by Lie sphere transformation to an isoparametric hypersurface in S n . [ABSTRACT FROM AUTHOR]

Microwave kinetic inductance detectors provide highly multiplexed arrays of detectors that can be configured to operate from the sub-millimeter to the x-ray regime. We have examined two tungsten silicide alloys (W5Si3 and WSi2), which are dense alloys that provide a critical temperature tunable with composition, large kinetic inductance fraction, and high normal-state resistivity. We have fabricated superconducting resonators and provide measurement data on critical temperature, surface resistance, quality factor, noise, and quasiparticles lifetime. Tungsten silicide appears to be promising for microwave kinetic inductance detectors. [ABSTRACT FROM AUTHOR]