Application of Machine Learning Methods to the Open-Loop Control of a Freeform Fabrication System

Freeform fabrication of complete functional devices requires the fabrication system to achieve well-controlled deposition of many materials with widely varying material properties. In a research setting, material preparation processes are not highly refined, causing batch property variation, and cost and time may prohibit accurate quantification of the relevant material properties, such as viscosity, elasticity, etc. for each batch. Closed-loop control based on the deposited material road is problematic due to the difficulty in non-contact measurement of the road geometry, so a labor-intensive calibration and open-loop control method is typically used. In the present work, k-Nearest Neighbor and Support Vector Machine (SVM) machine learning algorithms are applied to the problem of generating open-loop control parameters which produce desired deposited material road geometry from a description of a given material and tool configuration comprising a set of qualitative and quantitative attributes. Training data for the algorithms is generated in the course of ordinary use of the SFF system as the results of manual calibration of control parameters. Given the large instance space and the small training data set compiled thus far, the performance is quite promising, although still insufficient to allow complete automation of the calibration process. The SVM-based approach produces tolerable results when tested with materials not in the training data set. When control parameters produced by the learning algorithms are used as a starting point for manual calibration, significant operator time savings and material waste reduction may be achieved.Mechanical Engineerin

Co-targeting HGF/cMET Signaling with MEK Inhibitors in Metastatic Uveal Melanoma.

Patients with metastatic uveal melanoma usually die within 1 year of diagnosis, emphasizing an urgent need to develop new treatment strategies. The liver is the most common site of metastasis. Mitogen-activated protein kinase kinase (MEK) inhibitors improve survival in V600 BRAF-mutated cutaneous melanoma patients but have limited efficacy in patients with uveal melanoma. Our previous work showed that hepatocyte growth factor (HGF) signaling elicits resistance to MEK inhibitors in metastatic uveal melanoma. In this study, we demonstrate that expression of two BH3-only family proteins, Bim-EL and Bmf, contributes to HGF-mediated resistance to MEK inhibitors. Targeting HGF/cMET signaling with LY2875358, a neutralizing and internalizing anti-cMET bivalent antibody, and LY2801653, a dual cMET/RON inhibitor, overcomes resistance to trametinib provided by exogenous HGF and by conditioned medium from primary hepatic stellate cells. We further determined that activation of PI3Kα/γ/δ isoforms mediates the resistance to MEK inhibitors by HGF. Combination of LY2801653 with trametinib decreases AKT phosphorylation and promotes proapoptotic PARP cleavage in metastatic uveal melanoma explants. Together, our data support the notion that selectively blocking cMET signaling or PI3K isoforms in metastatic uveal melanoma may break the intrinsic resistance to MEK inhibitors provided by factors from stromal cells in the liver

RAC1 P29S regulates PD-L1 expression in melanoma.

Whole exome sequencing of cutaneous melanoma has led to the detection of P29 mutations in RAC1 in 5-9% of samples, but the role of RAC1 P29 mutations in melanoma biology remains unclear. Using reverse phase protein array analysis to examine the changes in protein/phospho-protein expression, we identified cyclin B1, PD-L1, Ets-1, and Syk as being selectively upregulated with RAC1 P29S expression and downregulated with RAC1 P29S depletion. Using the melanoma patient samples in TCGA, we found PD-L1 expression to be significantly increased in RAC1 P29S patients compared to RAC1 WT as well as other RAC1 mutants. The finding that PD-L1 is upregulated suggests that oncogenic RAC1 P29S may promote suppression of the antitumor immune response. This is a new insight into the biological function of RAC1 P29S mutations with potential clinical implications as PD-L1 is a candidate biomarker for increased benefit from treatment with anti-PD1 or anti-PD-L1 antibodies

Response and Resistance to Paradox-Breaking BRAF Inhibitor in Melanomas

FDA-approved BRAF inhibitors produce high response rates and improve overall survival in patients with BRAF V600E/K-mutant melanoma, but are linked to pathologies associated with paradoxical ERK1/2 activation in wild-type BRAF cells. To overcome this limitation, a next-generation paradox-breaking RAF inhibitor (PLX8394) has been designed. Here, we show that by using a quantitative reporter assay, PLX8394 rapidly suppressed ERK1/2 reporter activity and growth of mutant BRAF melanoma xenografts. Ex vivo treatment of xenografts and use of a patient-derived explant system (PDeX) revealed that PLX8394 suppressed ERK1/2 signaling and elicited apoptosis more effectively than the FDA-approved BRAF inhibitor, vemurafenib. Furthermore, PLX8394 was efficacious against vemurafenibresistant BRAF splice variant-expressing tumors and reduced splice variant homodimerization. Importantly, PLX8394 did not induce paradoxical activation of ERK1/2 in wild-type BRAF cell lines or PDeX. Continued in vivo dosing of xenografts with PLX8394 led to the development of acquired resistance via ERK1/2 reactivation through heterogeneous mechanisms; however, resistant cells were found to have differential sensitivity to ERK1/2 inhibitor. These findings highlight the efficacy of a paradox-breaking selective BRAF inhibitor and the use of PDeX system to test the efficacy of therapeutic agents. © 2017 American Association for Cancer Research

Fermentacja i proteoliza procesu kiszenia świeżej i podsuszonej zielonki z di- oraz tetraploidalnych form koniczyny czerwonej

form of red clover (2n – 4n), cultivars within the genetic form: 2n (Krynia, Parada), 4n (Jubilatka, Bona) and DM x form, DM x 2n, DM x 4n. Fermentation and proteolysis during the ensilage of red clover were affected primarily by wilting, whereas genetic factors (genetic form, cultivar) exerted a lesser effect. However, the genetic form of red clover affected the true protein content of silage and the extent of proteolysis during the ensiling process. The effect of the genetic form of red clover on the extent of proteolysis in silage (at similar levels of water-soluble carbohydrates and buffering capacity) suggests that diploid and tetraploid red clover cultivars differ with respect to chemical properties (poliphenol oxidase activity, polyphenol content) affecting proteolysis.Analizowano wpływ podsuszenia surowca, formy genetycznej koniczyny czerwonej (2n – 4n), odmiany w obrębie danej formy genetycznej: 2n (Krynia – Parada), 4n (Jubilatka – Bona) oraz SM x forma, SM x 2n, SM x 4n. Uzyskane wyniki wykazały dominujący wpływ czynnika podsuszenia nad czynnikami genetycznymi (forma genetyczna, odmiana) na przebieg fermentacji i zakres proteolizy podczas zakiszania koniczyny czerwonej. Stwierdzono jednak wpływ formy genetycznej koniczyny na zawartość białka właściwego w kiszonkach oraz stopień proteolizy w trakcie zakiszania. Stwierdzony wpływ formy genetycznej koniczyny na zakres proteolizy w kiszonkach (przy zbliżonym udziale cukrów rozpuszczalnych i pojemności buforowej zakiszanych zielonek) pozwala przypuszczać, że występuje zróżnicowanie innych chemicznych cech zielonek wpływających na proteolizę (aktywność PPO, zawartość polifenoli) między formami genetycznymi i odmianami

FOXD3 Regulates VISTA Expression in Melanoma.

Immune checkpoint inhibitors have improved patient survival in melanoma, but the innate resistance of many patients necessitates the investigation of alternative immune targets. Many immune checkpoint proteins lack proper characterization, including V-domain Ig suppressor of T cell activation (VISTA). VISTA expression on immune cells can suppress T cell activity; however, few studies have investigated its expression and regulation in cancer cells. In this study, we observe that VISTA is expressed in melanoma patient samples and cell lines. Tumor cell-specific expression of VISTA promotes tumor onset in vivo, associated with increased intratumoral T regulatory cells, and enhanced PDL-1 expression on tumor-infiltrating macrophages. VISTA transcript levels are regulated by the stemness factor Forkhead box D3 (FOXD3). BRAF inhibition upregulates FOXD3 and reduces VISTA expression. Overall, this study demonstrates melanoma cell expression of VISTA and its regulation by FOXD3, contributing to the rationale for therapeutic strategies that combine targeted inhibitors with immune checkpoint blockade

In vivo E2F reporting reveals efficacious schedules of MEK1/2–CDK4/6 targeting and mTOR–s6 resistance mechanisms

Targeting cyclin-dependent kinases 4/6 (CDK4/6) represents a therapeutic option in combination with BRAF inhibitor and/or MEK inhibitor (MEKi) in melanoma; however, continuous dosing elicits toxicities in patients. Using quantitative and temporal in vivo reporting, we show that continuous MEKi with intermittent CDK4/6 inhibitor (CDK4/6i) led to more complete tumor responses versus other combination schedules. Nevertheless, some tumors acquired resistance that was associated with enhanced phosphorylation of ribosomal S6 protein. These data were supported by phospho-S6 staining of melanoma biopsies from patients treated with CDK4/6i plus targeted inhibitors. Enhanced phospho-S6 in resistant tumors provided a therapeutic window for the mTORC1/2 inhibitor AZD2014. Mechanistically, upregulation or mutation of NRAS was associated with resistance in in vivo models and patient samples, respectively, and mutant NRAS was sufficient to enhance resistance. This study utilizes an in vivo reporter model to optimize schedules and supports targeting mTORC1/2 to overcome MEKi plus CDK4/6i resistance. SIGnIFICAnCE: Mutant BRAF and NRAS melanomas acquire resistance to combined MEK and CDK4/6 inhibition via upregulation of mTOR pathway signaling. This resistance mechanism provides the preclinical basis to utilize mTORC1/2 inhibitors to improve MEKi plus CDK4/6i drug regimens

Teenage Kicks:Girls growing up in Britain 1956-1974

This zine tells the stories of teenage girls growing up in Britain in 1956to 1974. It was inspired by a research project called ‘Girlhood and Later Life’ (seewww.manchester.ac.uk/girlhood-and-later-life). As part of this project, we interviewed women born between 1939 and 1952 about their experiences as teenagers and young women.The stories in Teenage Kicks are based on some of the stories they told us, though we have changed some details and added others.All these stories take place between the mid 1950s and the mid 1970s, which we often look back on as a time of great social, political and economic change. But change does not happen instantly, or equally. Some girls manage to take advantage of new opportunities and freedoms, but others get a taste of freedom that quickly dissolves or find themselves pulled into the same lives as generations of women before them

O discurso ambiental na mídia: a cobertura jornalística do meio ambiente

A história de como o meio ambiente acabou se tornando pauta quase que diária na mídia impressa. As diferentes correntes de discurso que circulam no meio. De que forma as mídias e os profissionais estão abordando o tema em questão e quais são seus principais desafios em uma sociedade na qual o imediatismo fala mais alto que as posturas em longo prazo. Uma análise e comparação entre os veículos da grande mídia e os especializados e de que maneira eles podem contribuir para uma maior conscientização da população em relação às causas ambientais