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Self-supervised learning (SSL) methods are enabling an increasing number of deep learning models to be trained on image datasets in domains where labels are difficult to obtain. These methods, however, struggle to scale to the high resolution of medical imaging datasets, where they are critical for achieving good generalization on label-scarce medical image datasets. In this work, we propose the Histopathology DatasetGAN (HDGAN) framework, an extension of the DatasetGAN semi-supervised framework for image generation and segmentation that scales well to large-resolution histopathology images. We make several adaptations from the original framework, including updating the generative backbone, selectively extracting latent features from the generator, and switching to memory-mapped arrays. These changes reduce the memory consumption of the framework, improving its applicability to medical imaging domains. We evaluate HDGAN on a thrombotic microangiopathy high-resolution tile dataset, demonstrating strong performance on the high-resolution image-annotation generation task. We hope that this work enables more application of deep learning models to medical datasets, in addition to encouraging more exploration of self-supervised frameworks within the medical imaging domain., Comment: 5 pages, 2 figures, 1 table. Submitted to IEEE SPMB conference

Objective : An international multidisciplinary initiative, jointly supported by the American College of Rheumatology and European Alliance of Associations for Rheumatology, is underway to develop new rigorous classification criteria to identify patients with high likelihood of antiphospholipid syndrome (APS) for research purposes. The present study was undertaken to apply an evidence- and consensus-based approach to identify candidate criteria and develop a hierarchical organization of criteria within domains. Methods : During phase I, the APS classification criteria steering committee used systematic literature reviews and surveys of international APS physician scientists to generate a comprehensive list of items related to APS. In phase II, we reviewed the literature, administered surveys, formed domain subcommittees, and used Delphi exercises and nominal group technique to reduce potential APS candidate criteria. Candidate criteria were hierarchically organized into clinical and laboratory domains. Results : Phase I generated 152 candidate criteria, expanded to 261 items with the addition of subgroups and candidate criteria with potential negative weights. Using iterative item reduction techniques in phase II, we initially reduced these items to 64 potential candidate criteria organized into 10 clinical and laboratory domains. Subsequent item reduction methods resulted in 27 candidate criteria, hierarchically organized into 6 additive domains (laboratory, macrovascular, microvascular, obstetric, cardiac, and hematologic) for APS classification. Conclusion : Using data- and consensus-driven methodology, we identified 27 APS candidate criteria in 6 clinical or laboratory domains. In the next phase, the proposed candidate criteria will be used for real-world case collection and further refined, organized, and weighted to determine an aggregate score and threshold for APS classification.

Objective: To explore whether APOBEC family members are involved in the response to inappropriate expression of L1 retroelements in primary Sjögren's syndrome (SS) and systemic lupus erythematosus (SLE), as well as in SS related lymphomagenesis. Methods: Minor salivary glands (MSG) and kidney biopsy (KB) specimens were obtained from 41 SS patients (10 with lymphoma) and 23 patients with SLE, respectively. PBMC and sera were also collected from 73 SLE patients. Full-length L1 transcripts, members of the APOBEC and IFN family were quantitated by real time PCR. Type I IFN activity was assessed in lupus plasma by a cell assay. Results: APOBEC3A was increased in SS MSG, SLE KB and PBMC and correlated with L1. AID and APOBEC3G were particularly overexpressed in MSG tissues derived from SS lymphoma patients. Conclusion: These data reveal a previously unappreciated role of APOBEC family proteins in the pathogenesis of systemic autoimmunity and SS related lymphomagenesis. © 2020

The XIII Banff meeting, held in conjunction the Canadian Society of Transplantation in Vancouver, Canada, reviewed the clinical impact of updates of C4d‐negative antibody‐mediated rejection (ABMR) from the 2013 meeting, reports from active Banff Working Groups, the relationships of donor‐specific antibody tests (anti‐HLA and non‐HLA) with transplant histopathology, and questions of molecular transplant diagnostics. The use of transcriptome gene sets, their resultant diagnostic classifiers, or common key genes to supplement the diagnosis and classification of rejection requires further consensus agreement and validation in biopsies. Newly introduced concepts include the i‐IFTA score, comprising inflammation within areas of fibrosis and atrophy and acceptance of transplant arteriolopathy within the descriptions of chronic active T cell–mediated rejection (TCMR) or chronic ABMR. The pattern of mixed TCMR and ABMR was increasingly recognized. This report also includes improved definitions of TCMR and ABMR in pancreas transplants with specification of vascular lesions and prospects for defining a vascularized composite allograft rejection classification. The goal of the Banff process is ongoing integration of advances in histologic, serologic, and molecular diagnostic techniques to produce a consensus‐based reporting system that offers precise composite scores, accurate routine diagnostics, and applicability to next‐generation clinical trials., In this article, the Banff consortium presents the most updated version of the kidney, pancreas, and VCA transplant rejection classification and prospects for implementing intragraft molecular assessment. See the companion report on page 42.

Objective: To investigate whether altered DNA methylation contributes to the inappropriate expression of LINE-1 (L1) retroelements in primary Sjogren's syndrome (SS) and systemic lupus erythematosus (SLE). Methods: Minor salivary glands (MSG) were obtained from 42 patients with primary SS [23 without adverse predictors for lymphoma development (SS-low risk), 7 SS-high risk and 12 complicated by B-cell lymphoma (SS-lymphoma)] and 17 sicca controls (SC). Additionally, kidney biopsy specimens and PBMCs were obtained from 23 and 73 lupus patients, respectively. Relative mRNA expression was quantified for full-length L1 transcripts, along with mediators of methylation. In an independent set of 44 MSG samples (11 SS-low risk, 10 SS-high risk, 15 SS-lymphoma and 8 SC), methylation levels of the L1 promoter were determined by bisulphite pyrosequencing. Results: A strong positive correlation was demonstrated between L1 transcripts and gene products that mediate de novo and constitutive DNA methylation, DNA methyltransferase (DNMT)3B, DNMT1, and methyl CpG binding protein 2 (MeCP2), in both SS MSG and lupus renal tissues. A significant negative correlation was observed between expression of L1 and lymphoid-specific helicase (LSH, encoded by HELLS) in both SS MSG and SLE kidney tissues, as well as between DNMT3A transcripts and L1 expression in SLE kidney tissues and PBMCs. Reduced levels of L1 promoter methylation along with increased DNMT3B, DNMT1, and MeCP2, but reduced LSH levels were detected in SS-low risk patients compared to both SS-lymphoma and SC. The SS-lymphoma group was also characterized by a profound decrease of MeCP2 and DNMT3B compared to SC. Conclusion: Our data support a contributory role of altered methylation mechanisms in the pathogenesis of systemic autoimmune disorders and related lymphoproliferative processes and suggest that LSH and DNMT3A should be investigated as candidate upstream mediators of decreased L1 promoter methylation and increased L1 expression. © 2017 Elsevier Ltd

Motivated by limitations in today’s host-centric IP network, recent studies have proposed clean-slate network architectures centered around alternate first-class principals, such as content, services, or users. However, much like the host-centric IP design, elevating one principal type above others hinders communication between other principals and inhibits the network’s capability to evolve. This paper presents the eXpressive Internet Architecture (XIA), an architecture with native support for multiple principals and the ability to evolve its functionality to accommodate new, as yet unforeseen, principals over time. We describe key design requirements, and demonstrate how XIA’s rich addressing and forwarding semantics facilitate flexibility and evolvability, while keeping core network functions simple and efficient. We describe case studies that demonstrate key functionality XIA enables.

Tensile strength and fracture toughness of two magnesium metal matrix composites

Reinforcement of magnesium alloys with ceramic particulates has engineered a new family of materials that are marketed under the trade name metal-matrix composites. Rapid strides in the processing of these materials during the last two decades have provided the necessary impetus for their emergence and use in structural and automotive-related components. In this article we report the results of a study aimed at understanding the role of particulate reinforcements on the tensile, compressive, impact deformation and overall fracture behaviour of magnesium alloy discontinuously-reinforced with siliconcarbide particulates and saffil alumina short fibres. An increase in reinforcement content was observed to have a marginal influence on strength and detrimental influence on ductility compared to the un-reinforced counterpart. Micro-cracking in the metal matrix coupled with failure of the reinforcing phase (i.e. particulates or shortfibres), both independently dispersed and in clusters, dominated the fracture sequence at the microscopic level. The deformation and final fracture behaviour of the composite materials are discussed in light of the concurrent and mutually interactive influences of microstructural effects; deformation characteristics of the composite constituents,nature of loading and local stress state.

Magnesium alloys are very suitable for applications that require materials with high strength-to-weight ratio. However, the use of magnesium alloys is limited due to their low elevated temperature properties. Magnesium matrix composites are the possible alternatives. The present work involved the production and subsequent property evaluation of AM100 magnesium alloy and its alumina short fibre reinforced composites. Studies on microstructure, hardness, density, stiffness, tensile properties, impact strength, wear resistance and corrosion resistance were carried out. Results indicate the significant improvement in the properties achieved by making composites. The findings also highlight the dominant roles of the base alloy matrix and the fibre volume fraction in determining the above properties.

Squeeze casting is a near-net-shape process that is rapidly gaining popularity due to its simplicity and effciency. During the past few years Al alloys and Zn alloys have been produced through squeeze casting and their mechanical properties have been studied [1, 2].

Network protocols in cellular wireless data networks must update routes as a mobile host moves between cells. These routing updates combined with some associated state changes are called handoffs. Most current handoff schemes in wireless networks result in data loss or large variations in packet delivery times. Unfortunately, many applications, such as real-time multimedia applications and reliable transport protocols, adapt to long term estimates of end-to-end delay and loss. Violations and rapid fluctuations of these estimates caused by handoff processing often result in degraded performance. For example, loss during handoff adversely affects TCP performance [4], and high packet loss and variable delays result in poor real-time multimedia performance. In this paper, we describe a multicast-based protocol that eliminates data loss and incurs negligible delays during a handoff. The basic technique of the algorithm is to anticipate a handoff using wireless network information in the form of received signal strengths and to multicast data destined for the mobile host to nearby base stations in advance. This routing, combined with intelligent buffering techniques at the base stations, enables very rapid routing updates and eliminates data loss without the use of explicit data forwarding. We have implemented this protocol using IP Multicast and Mobile IP-like routing. In our implementation, handoffs typically take between 8 and 15 ms to complete and result in no data loss.

brusive Jet Machining (AJM) or Micro Blast Machining is a non-traditional machining process, wherein material removal is effected by the erosive action of a high velocity jet of a gas, carrying fine-grained abrasive particles, impacting the work surface. The AJM process differs from conventional sand blasting in that the abrasive is much finer and the process parameters and cutting action are carefully controlled. The process is particularly suitable to cut intricate shapes in hard and brittle materials which are sensitive to heat and have a tendency to chip easily. In other words, AJM can handle virtually any hard or brittle material. Already the process has found its ways Into dozens of applications; sometimes replacing conventional alternatives often doing jobs that could not be done in any other way. This paper reviews the current status of this non-conventional machining process and discusses the unique advantages and possible applications.

Zinc-aluminium cast alloys (ZA alloys) exhibit good castability and mechanical properties but these alloys lack creep resistance and high temperature stability. One solution to improve these properties is to reinforce with ceramic particles or fibres, to result in MMCs. MMCs can be produced using casting technique involving infiltration. A systematic investigation was taken and this paper discusses the salient findings of the study on the ZA-27 alloy based MMCs produced through squeeze casting. (Reinforcing fibers: SAFFIL (chopped alumina) or mullite.)

An experimental investigation was carried out to Characterise the performance of four types of cast iron under adhesive wear, erosive wear, cavitation erosion and low frequency thermal cycling. Results indicate that vermicular graphite iron has the best rating among the cast irons investigate,based on the overall performance as well as cost consideration.

In recent years, compacted graphite cast iron was a good substitute for several industrial applications that involve wear. The adhesive wear characteristics of compacted graphite iron and flake graphite iron were investigated in this work. It was found that the coefficient of friction is lower for compacted graphite iron. For both cast irons, the influence of microstructure and graphite morphol. on the wear process was studied and discussed in this paper. Compacted graphite iron seems to have good potential as a substitute material for applications involving adhesive wear.

Zinc-aluminum alloys (which are known as the alloys of the 80's) have found several newer applications in recent years. The microstructural features of MMCs based on zinc-27% aluminum alloy (ZA-27) were studied with a view to analyze the interfacial bonding and the distribution of different elements on the matrix. The findings are briefly discussed.

The mechanical alloying process has been reviewed in this paper. The research and development on nickel, iron, aluminum, titanium, and copper base MA alloys, and commercially available alloys are discussed.

Vermicular graphite cast iron is a new addition to the family of cast irons. Various methods for producing vermicular graphite cast iron are briefly discussed in this paper. The mechanical and physical properties of cast irons with vermicular graphite have been found to be intermediate between those of gray and ductile irons. Other properties such as casting characteristics, scaling resistance, damping capacity and machinability have been compared with those of gray and ductile irons. Probable applications of vermicular graphite cast irons are suggested.

The fractographic features of unalloyed and alloyed compacted graphite (CG) cast irons which failed in tension and in fatigue testing modes are reported. For comparison, the features of gray and ductile iron are also included. Generally, brittle fracture features were observed. The investigation led to the conclusion that fracture surface details of compacted form of irons are a blend of gray and ductile irons. Heat treatment and alloying affect the properties as well as the failure mode.

Use of $Na_2SiF_6$ powder and ester liquid as hardeners with Na silicate was studied. In each binder system, studies were conducted on the setting characteristics of sands bonded with different binders and hardener levels. Sand mixures were analyzed by using SEM and x-ray diffraction to determine the nature of the bond formed. Experiments were conducted to assess permeability, friability, knockout, and thermal properties of the sand mixts. $Na_2SiF_6$ and ester containing 90 diacetin and 10% triacetin were hardeners for Na silicate bonded sands.

The heat pipe is an innovative engineering structure characterized by its capacity to transfer large quantities of heat through relatively small cross-sectional areas with very small temperature differences; it also possesses high thermal conductance and low thermal impedance. In recent times, heat pipes in various forms and designs have found a wide variety of applications. This paper briefly presents the basic concepts of heat pipes, recent innovations in design and their applications.

Compacted graphite cast iron (CG cast iron) has some advantages over ductile and gray irons in production and use. Cast irons with compacted graphite can be produced either by deliberate undertreatment with nodularizers or by a simultaneous treatment with nodularizers and antinodularizers. Experimental investigations show that repetitive production is possible using either of the above methods. The properties of CG cast irons thus produced were assessed and the mechanical properties correlated with the aspect ratio of graphite. The CG cast irons have mechanical properties, machinability, wear resistance, and corrosion characteristics intermediate to those of gray and ductile irons. The reason for the intermediate behavior of the CG cast irons is explained based on the microstructure and the graphite shape. Using SEM studies, attempts were made to study the morphological and growth behavior of the compacted graphite. It is confirmed that, in CG cast iron, graphite growth takes place perpendicular to the basal plane of graphite.