30 research outputs found
Tribochemical Analysis of Si-Doped and Non-Doped Diamond-Like Carbon for Application Within the Internal Combustion Engine
Due to the ever-increasing global drivers focused on increasing fuel economy in tandem with decreasing the environmental impact of automobile usage; the automotive sector is rapidly embracing widespread use of Diamond-Like Carbon (DLC) coatings. DLC coatings have the potential to reduce the required level of many traditional oil additives that can negatively impact on both the environment and certain parts of the car engine, specifically the catalytic converter. Furthermore DLC shows promise with regards to reducing friction and can be highly efficacious at reducing wear. The field of research into DLC is ever-developing and many examples of doped DLCs exist. Currently, there is no firm consensus on which dopants are best to include in the DLC matrix when it is being employed within the automotive field. Adding to this the lack of a sufficient understanding of how current engine oil additives interact with DLC; the motivation for undertaking an in-depth analysis of both a-C:H and Si-DLC with current engine oils is clear.
This thesis addresses these issues and presents evidence on how both Si-DLCs and a-C:H DLCs interact with current engine oil additives to reduce wear in the engine. The fundamental tribochemistry governing DLC’s interactions at the interfaces are explored with specific reference to wearing of Si-DLCs. Tribological experiments are undertaken to emulate certain conditions within an engine using both reciprocating pin-on-plate tribometers and pin-on-disc tribometers. A novel Si-DLC is created and tested to explore the effect of tri-doping on the coating. Advanced surface analysis techniques are used to gain a full understanding of what processes have taken place at the interfaces. This includes use of X-ray Photoelectron Spectroscopy, Secondary Ion Mass Spectrometry and scanning light interferometry. Key findings include the effect that Si doping has on the DLC coating with regards to structure, friction and wear. The fundamental observation that the Si-DLCs examined consistently exhibited wear at higher rates when compared to the a-C:
ALK Status Testing in Non–Small-Cell Lung Carcinoma by FISH on ThinPrep Slides with Cytology Material
Introduction:Oncogenic anaplastic lymphoma kinase (ALK) gene rearrangements in non–small-cell lung carcinomas (NSCLC) provide the basis for targeted therapy with crizotinib and other specific ALK inhibitors. Treatment eligibility is conventionally determined by the Food and Drug Administration–approved companion diagnostic fluorescence in situ hybridization (FISH) assay on paraffin-embedded tissue (PET). On limited samples such as fine needle aspiration–derived cytoblocks, FISH for ALK is often uninformative. FISH performed on liquid-based ThinPrep slides (ThinPrep-FISH) may represent a robust alternative.Methods:Two hundred thirty cytology samples from 217 patients with advanced NSCLC, including a consecutive series of 179 specimens, were used to generate matched ThinPrep slides and paraffin cytoblocks. The same ThinPrep slides used for cytologic diagnosis were assessed by standard ALK break-apart two-color probe FISH, after etching of tumor areas. Ultrasensitive ALK immunohistochemistry (IHC) on corresponding cytoblocks [D5F3 antibody, OptiView signal amplification] served as the reference data set.Results:ThinPrep-FISH ALK signals were robust in 228 of 230 cases and not compromised by nuclear truncation inherent in paraffin-embedded tissue–FISH; only two samples displayed no signals. Nine of 178 informative cases (5%) in the consecutive series and 18 of 228 informative cases (7.8%) overall were ALK rearranged by ThinPrep-FISH. In 154 informative matched ThinPrep-FISH and cytoblock-IHC samples, 152 were concordant (10, 6.5% ALK status positive; 142, 92.2% ALK status negative), and two (1.3%) were ThinPrep-FISH positive but IHC negative (sensitivity 100%, specificity 98.6%, overall agreement 98.7%).Conclusion:Detection of ALK gene rearrangements in liquid cytology ThinPrep slides derived from patients with NSCLC can be confidently used for clinical ALK molecular testing
Molecular mechanism of ligand recognition by membrane transport protein, Mhp1
The hydantoin transporter Mhp1 is a sodium-coupled secondary active transport protein of the nucleobase-cation-symport family and a member of the widespread 5-helix inverted repeat superfamily of transporters. The structure of Mhp1 was previously solved in three different conformations providing insight into the molecular basis of the alternating access mechanism. Here, we elucidate detailed events of substrate binding, through a combination of crystallography, molecular dynamics, site-directed mutagenesis, biochemical/biophysical assays, and the design and synthesis of novel ligands. We show precisely where 5-substituted hydantoin substrates bind in an extended configuration at the interface of the bundle and hash domains. They are recognised through hydrogen bonds to the hydantoin moiety and the complementarity of the 5-substituent for a hydrophobic pocket in the protein. Furthermore, we describe a novel structure of an intermediate state of the protein with the external thin gate locked open by an inhibitor, 5-(2-naphthylmethyl)-L-hydantoin, which becomes a substrate when leucine 363 is changed to an alanine. We deduce the molecular events that underlie acquisition and transport of a ligand by Mhp1
An integrated analysis of Maglemose bone points reframes the Early Mesolithic of Southern Scandinavia
The extensive peat bogs of Southern Scandinavia have yielded rich Mesolithic archaeological assemblages, with one of the most iconic artefacts being the bone point. Although great in number they remain understudied. Here we present a combined investigation of the typology, protein-based species composition, and absolute chronology of Maglemosian bone points. The majority of the bone points are made from cervids and bovines. However, changes both in species composition and barb morphology can be directly linked to a paucity of finds lasting nearly 600 years in Southern Scandinavia around 10,300 cal BP. We hypothesize that this hiatus was climate-driven and forced hunter-gatherers to abandon the lakes. Furthermore, the marked change in bone points coincides with a change in lithic technology. We, therefore, propose that the Maglemose culture in Southern Scandinavia is fundamentally divided into an Early Complex and a Late Complex
A first step towards practical single cell proteomics: a microfluidic antibody capture chip with TIRF detection
Catholic Youth Council: A Study of the Youth Department, Diocese of Buffalo, 1941-1953
In order to give this presumption more reality it is first intended to give an overall background of the Catholic Youth Apostolate in the United States citing the writings of Archbishop Cicognani, and Cardinal Pizzardo. It is pro- posed furthermore to give a historical sketch of the Youth Apostolate in the United States; to describe the area served by the Diocese of Buffalo; to give the historical development of the Youth Department from its inception to its present status; to develop and define the four fold 1 aspect of the program; to outline the department\u27s philosophy on volunteers; to describe the council plan of organization and how it fulfills the mandate of the bishops; to visualize for the reader the specialized events that highlight the program year and finally to present to the reader the staff and their duties as well as a description of the physical set-up of the building housing the Youth Department
Spontaneous sphenopalatine pseudoaneurysm: recurrent epistaxis in a patient with cryptogenic vasculopathy
Data for figs 8 and 9 from Pressure induced transformation of biomass to a highly durable, low friction film on steel
Herein the authors report a detailed insight into the tribological and chemical mechanisms that take place when leaf matter is present at the wheel/rail interface. The approaches used enables further insight into the formation and subsequent effects on friction from leaf derived layers. Results shed insight on the process that facilitate the formation of leaf derived layers, their structure and chemical make-up. Our analysis indicates that polyphenols, a chemical family that include tannins, have an important role in layer formation and hypothesis on the layer's stability, when formed under high pressures. The data indicate that the high pressure found at the wheel/rail interface facilitates conversion of biomass into a tenacious, thin film. This is shown by the increase in the amount of phenolic compounds present. Phenolic compounds are typically rich in oxygen functional groups that have the ability to bind to metal ions. This insight into the composition of the film is expected to enable the development of novel remediation strategies. It highlights the potential for cleaning agents to be used as tools for restoring friction to safe values. This should lead to improvements in the operational performance and safety of rail transport for passengers and train operators