Some innovative surface texturing techniques for tribological purposes

This paper reviews methods for texturing surfaces for tribological applications and presents some innovative methods that could make surface texturing more cost-effective. Possible texturing methods were identified and classified according to their physical principles. This involved identifying existing texturing methods and also led to proposals for new possible methods. Three innovative texturing methods with low cost and high texturing speed are then presented: (i) a simpler and cheaper version of photochemical texturing, (ii) maskless electrochemical texturing, and (iii) masking surfaces by ink-jet printing followed by etching. From these, maskless electrochemical texturing was the cheapest and fastest, but the minimum size of the texture features was the largest. Ink-jet printing followed by etching is an alternative that may potentially provide a good combination of cost and resolution, but the texturing time depends on the surface area. Then, an attempt was made to delimit tribological applications where the use of such processes could be beneficial, based on analysis of experimental results of their tribological evaluation. These showed that the methods proposed could be particularly suited for components with contact areas larger than the width of the texture features under either hydrodynamic lubrication or starved lubrication. This work was supported by Fapemig/Brazil, Capes/Brazil, and the Royal Society (UK)This version is the author accepted manuscript. The final published article can be found here: http://pij.sagepub.com/content/early/2014/06/18/1350650114539936.full.pdf+htm

Neutralisation and the perception of close-mid and open-mid vowels: the gradient between phonological categories

A prototype theoretical framework was the basis of a study on the impact of neutralisation on the perception of Portuguese close-mid and open-mid vowels and the gradient between phonological categories. Fifteen Portuguese listeners from Lisbon participated in identification and goodness rating tasks of 20 random repetitions of 31 stimuli from a /i/-/e/-/ε/-/a/ continuum. Boundaries between categories were explored using logistic regression curves and analysis of variance. Results from the identification task revealed four vowel categories marked by three statistically distinct boundaries. The prototype of a category, i.e., the stimulus with the highest goodness rating score, was approximately in the centroid and the goodness score decreased as the stimulus moved away from this centroid. The boundary between /e/ and /ε/, the underlying opposition that neutralises at surface level, was less steep than between /ε/ and /a/, the opposition that never neutralises, a possible influence of the phonological system on speech perception

Edge effects in 3D dosimetry: characterisation and correction of the non-uniform dose response of PRESAGE®.

Previous work has shown that PRESAGE® can be used successfully to perform 3D dosimetric measurements of complex radiotherapy treatments. However, measurements near the sample edges are known to be difficult to achieve. This is an issue when the doses at air-material interfaces are of interest, for example when investigating the electron return effect (ERE) present in treatments delivered by magnetic resonance (MR)-linac systems. To study this effect, a set of 3.5 cm-diameter cylindrical PRESAGE® samples was uniformly irradiated with multiple dose fractions, using either a conventional linac or an MR-linac. The samples were imaged between fractions using an optical-CT, to read out the corresponding accumulated doses. A calibration between TPS-predicted dose and optical-CT pixel value was determined for individual dosimeters as a function of radial distance from the axis of rotation. This data was used to develop a correction that was applied to four additional samples of PRESAGE® of the same formulation, irradiated with 3D-CRT and IMRT treatment plans, to recover significantly improved 3D measurements of dose. An alternative strategy was also tested, in which the outer surface of the sample was physically removed prior to irradiation. Results show that for the formulation studied here, PRESAGE® samples have a central region that responds uniformly and an edge region of 6-7 mm where there is gradual increase in dosimeter response, rising to an over-response of 24%-36% at the outer boundary. This non-uniform dose response increases in both extent and magnitude over time. Both mitigation strategies investigated were successful. In our four exemplar studies, we show how discrepancies at edges are reduced from 13%-37% of the maximum dose to between 2 and 8%. Quantitative analysis shows that the 3D gamma passing rates rise from 90.4, 69.3, 63.7 and 43.6% to 97.3, 99.9, 96.7 and 98.9% respectively

Dose verification of dynamic MLC-tracked radiotherapy using small PRESAGE (R) 3D dosimeters and a motion phantom

With the increasing complexity of radiotherapy treatments typical 1D and 2D quality assurance (QA) detectors may fail to detect out-of-plane dose discrepancies, in particular in the presence of motion. In this work, small samples of the PRESAGE® 3D radiochromic dosimeter were used in combination with a motion phantom to measure real-time multileaf collimator (MLC)-tracked radiotherapy treatments. A different sample of PRESAGE® was irradiated for each of three different irradiation scenarios: (1) static: static sample, without tracking (2) motion: moving sample, without tracking and (3) tracking: moving sample, with tracking. Our in-house software DynaTrack dynamically moves the linac's MLC leafs based on the target position. The doses delivered to the samples were reconstructed based on the recorded positions of the MLC and phantom during the beam delivery. PRESAGE® samples were imaged with an in-house optical-CT scanner. Comparison between simulated and measured 3D dose showed good agreement for all three irradiation scenarios (static: 99.2%; motion: 99.7%; tracking: 99.3% with a 3%, 2 mm and a 10% threshold local gamma criterion), failing only at the edges of the PRESAGE® samples (~ 6 mm). Given that the dose distributions deposited using the DynaTrack system have been independently verified, this experiment demonstrates the ability of PRESAGE to measure 3D doses correctly in a tracking context. We conclude that this methodology could be used in the future to validate the delivery of dynamic MLC-tracked radiotherapy

The importance of serological assays in diagnosing acute pulmonary histoplasmosis

Histoplasmosis is a systemic mycosis caused by inhalation of Histoplasma capsulatum microconidia. The disease does not normally affect immunocompetent individuals after a single, transient inhalation exposure. However, longer exposure may cause chronic or disseminated acute pulmonary infection. Herein, we report the case of a 24-year-old immunocompetent patient, who presented fever, cough and dyspnea for one month. The chest radiography revealed interstitial infiltrate and diffuse micronodules. The patient reported having had close and prolonged contact with bats. Diagnosis was confirmed by positive double immunodifusion and immunoblotting assays. She was treated with ketoconazole (400 mg) and there was complete resolution of the disease

Komparasi Morfologi Beberapa Koloni Jamur Akar Putih (Rigidoporus Microporus) Dari Perkebunan Karet Di Jawa Tengah Dan Sumatera Selatan

Rigidoporus microporus adalah jamur yang menyebabkan penyakit jamur akar putih (JAP) pada tanaman karet. Tingkat keparahan penyakit yang ditimbulkan oleh JAP berbeda antar wilayah. Penelitian ini bertujuan untuk mengetahui komparasi morfologi beberapa koloni jamur akar putih dari perkebunan karet di Jawa Tengah dan Sumatera Selatan. Sampel dikoleksi langsung dari perkebunan Merbuh dan Blimbing di Jawa Tengah dan Balai Penelitian Karet Sembawa di Sumatera Selatan. Penelitian dilakukan pada bulan November 2016-April 2017 di Laboratorium Carotenoid Antioxidant Research Center (CARC) Universitas Kristen Satya Wacana, Salatiga. Hasil yang diperoleh menunjukkan bahwa kecepatan pertumbuhan ke-17 isolat berdasar penambahan diameter koloni hingga mencapai tepi petri bervariasi yaitu 4 hari (MB8), 6 hari (MM6), 7 hari (MK2, MK3, SS1), 8 hari (MK1, MM5, MM7, SS2, SS3), 9 hari (BW1, SS5), 10 hari (MK4, BW4, SS4), 11 hari (BW2), dan 13 hari (BB3). Morfologi koloni dan hifa JAP baik dari Jawa Tengah maupun Sumatera Selatan hampir sama, yakni koloni berbentuk bulat, filamentous, elevasi ada yang rata (flat) dan ada yang sedikit timbul (raised), serta berwarna putih hingga putih gading. Hifa JAP memiliki septa, hialin, bercabang, dan tidak ada clamp connection

The Oncolytic Caprine Herpesvirus 1 (CpHV-1) Induces Apoptosis and Synergizes with Cisplatin in Mesothelioma Cell Lines: A New Potential Virotherapy Approach.

Malignant mesothelioma (MM) is an aggressive asbestos-related cancer, against which no curative modalities exist. Oncolytic virotherapy is a promising therapeutic approach, for which MM is an ideal candidate; indeed, the pleural location provides direct access for the intra-tumoral injection of oncolytic viruses (OVs). Some non-human OVs offer advantages over human OVs, including the non-pathogenicity in humans and the absence of pre-existing immunity. We previously showed that caprine herpesvirus 1 (CpHV-1), a non-pathogenic virus for humans, can kill different human cancer cell lines. Here, we assessed CpHV-1 effects on MM (NCI-H28, MSTO, NCI-H2052) and non-tumor mesothelial (MET-5A) cells. We found that CpHV-1 reduced cell viability and clonogenic potential in all MM cell lines without affecting non-tumor cells, in which, indeed, we did not detect intracellular viral DNA after treatment. In particular, CpHV-1 induced MM cell apoptosis and accumulation in G0/G1 or S cell cycle phases. Moreover, CpHV-1 strongly synergized with cisplatin, the drug currently used in MM chemotherapy, and this agent combination did not affect normal mesothelial cells. Although further studies are required to elucidate the mechanisms underlying the selective CpHV-1 action on MM cells, our data suggest that the CpHV-1-cisplatin combination could be a feasible strategy against MM