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Sirtuin 2 (Sirt2) is a member of the sirtuin family of NADdependent lysine deacylases and plays important roles in regulation of the cell cycle and gene expression. As a nucleocytoplasmic deacetylase, Sirt2 has been shown to target both histone and nonhistone acetylated protein substrates. The central catalytic domain of Sirt2 is flanked by flexible N and C termini, which vary in length and composition with alternative splicing. These termini are further subject to posttranslational modifications including phosphorylation. Here, we investigate the function of the N and C termini on deacetylation of nuclear substrates by Sirt2. Remarkably, we find that the C terminus autoinhibits deacetylation, while the N terminus enhances deacetylation of proteins and peptides, but not nucleosomes—a chromatin model substrate. Using protein semisynthesis, we characterize the effect of cell cycle-linked N-terminal phosphorylation at two major phosphorylation sites (Ser23/Ser25) and find that these further enhance protein/peptide deacetylation, with no effect on nucleosome deacetylation. Additionally, we find that VRK1, an established binding partner of both Sirt2 and nucleosomes, can stimulate deacetylation of nucleosomes by Sirt2, likely through an electrostatic mechanism. Taken together, these findings reveal multiple mechanisms regulating the activity of Sirt2, which allow for a broad range of activities across its multiple biological roles. [ABSTRACT FROM AUTHOR]

Coilable booms made of thin-ply composites provide mass and volume efficiency for deploying large structures in space. The recovered shape of the booms after being stowed in the coiled configuration is critical to the deployed stiffness and shape precision of the spacecraft, but is heavily influenced by the viscoelasticity of the polymer composites. A numerical study of coiling, stowing, uncoiling and shape recovery of a viscoelastic thin-ply composite coilable boom is presented in this paper. The formulation of two micromechanics-based viscoelastic shell models and their numerical implementation in structural simulations are presented. The shape recovery of a composite boom coiled for two years, replicating the typical timeline for deployable structures used in solar sail missions, has been simulated. The demonstrated modeling and simulation capability is useful for designing deployable spacecraft structures. • Ply homogenization computes viscoelastic stiffness faster than laminate homogenization. • Ply homogenization has comparable accuracy to laminate homogenization. • Composite deployable booms for solar sails have minimal distortions after stowage. [ABSTRACT FROM AUTHOR]

Recently, nanofiber-based wound dressings are currently a viable strategy to expedite the healing of wounds by providing a suitable microenvironment for tissue growth with active ingredients. This research study subjects the development of electrospun cellulose acetate (CA) nanofibers loaded with the XLAsp-P2, an antimicrobial peptide (AMP) that holds great potential for enhanced wound healing as a therapeutic agent. The synthesized XLAsp-P2-loaded CA nanofibers were fabricated via three loading percentages, 0.1 %, 0.2 %, and 0.3 % w/w, and characterized and evaluated their antimicrobial potential with MTT assay and Agar overlay methods as an alternative strategy. FT-IR analysis confirmed the compatibility of the peptide-loaded CA nanocomposite, showing distinct peaks corresponding to the constituent materials. Scanning electron microscopy (SEM) analysis was employed to characterize the morphology of electrospun peptide CA nanocomposites and illustrate the fiber's size at the nanoscale. The in vitro release study during the 24 hr, 87 % of the peptide was released which was approximately 5.2 mg; which was closer matched to the square root model of Higuchi at room temperature. MTT assay presented sensitive results towards Gram-positive bacteria compared to Gram Negative bacteria; which corresponded to the inhibition zones of the Agar overlay method proving that Escherichia coli (ATCC 25922) 17.66 ± 0.38 mm and Pseudomonas aeruginosa (ATCC 27853) 17.44 ± 0.38 mm exhibited moderate susceptibility, while Staphylococcus aureus (ATCC 25923)19.89 ± 0.69 mm and Bacillus cereus (ATCC 11778) 23.00 ± 0.33 mm showed promising responses. Collectively, The study's findings indicate that the XLAsp-P2 incorporated CA mat possesses an opportunity to function as an efficient platform for delivering therapeutic peptides. [Display omitted] [ABSTRACT FROM AUTHOR]

Australian manufacturing trade has witnessed a significant structural change in the past two decades. One of the noticeable developments has occurred in the area of parts and components (PCs) trade—a phenomenon that has been observed globally. Our analysis suggests that exports of PCs from Australia has fallen marginally while their imports in total manufacturing trade remains very high. A fall in the share of PCs exports is not surprising given the migration of PCs producing firms from Australia to low-cost production locations in Asia. We observe a dramatic increase in the shares of Asian countries in PCs imports to Australia while a falling share of NAFTA and EU countries. Econometric results based on panel data suggest that market size, the distance between trading partners, proximity to Asia and common language are important determinants in explaining a surge in PCs trade in Australian manufacturing. [ABSTRACT FROM AUTHOR]

Abstract Calculation of oil droplet size distribution is one of the key components of ocean oil spill models. Oil fate and transport calculations of the model are significantly impacted by the droplet size distribution. Accuracy of the model predictions heavily depend on how well the model can calculate or represent oil droplet sizes. However, in early oil spill models, the importance of oil droplet size calculation has been overlooked and they used simple empirical formulas. In recent decades, there have been some significant improvements in understanding of oil droplet size calculations. Both experimental studies as well as numerical studies have been contributed to improve oil droplet size calculations. The traditional equilibrium models have been improved while droplet dynamics models provided a different dimension to the oil DSD calculations. Thus, at this stage it is important to review the existing studies and methods of oil droplet size calculation. The objective of this paper is to review the development of oil droplet size calculation in ocean oil spill models highlighting the recent improvements. Furthermore, this paper discusses the capabilities and limitations of different approaches in calculating oil droplet size distribution in both underwater and surface oil spill models and discuss their applicability to different situations. This study will provide a good guideline for future oil spill model developments to improve the oil droplet size calculations. Highlights • Discuss the importance of oil droplet size calculations in ocean oil spill models • Summarizes the existing key studies on oil droplet size calculation in both surface and subsurface oil spills • Analyze different approaches for droplet size calculation in ocean oil spills with their advantages and disadvantages • Discuss the recent developments in population dynamic models and equilibrium models • The breakup and coalescence concepts, which are the basis for population dynamic models, are also discussed [ABSTRACT FROM AUTHOR]

Numerous proteases, such as matrix metalloproteinases (MMPs), cathepsins (CTS), and urokinase plasminogen activator (UpA), are dysfunctional (that is, over- or under-expressed) in solid tumors, when compared to healthy human subjects. This offers the opportunity to detect early tumors by liquid biopsies. This approach is of particular advantage for the early detection of pancreatic cancer, which is a “silent killer”. We have developed fluorescence nanobiosensors for ultrasensitive (sub-femtomolar) arginase and protease detection, consisting of water-dispersible Fe/Fe 3 O 4 core/shell nanoparticles and two tethered fluorescent dyes: TCPP (Tetrakis(4-carboxyphenyl)porphyrin) and cyanine 5.5. Upon posttranslational modification or enzymatic cleavage, the fluorescence of TCPP increases, which enables the detection of proteases at sub-femtomolar activities utilizing conventional plate readers. We have identified an enzymatic signature for the detection of pancreatic adenocarcinomas in serum, consisting of arginase, matrix metalloproteinase-1, -3, and - 9, cathepsin-B and -E, urokinase plasminogen activator, and neutrophil elastase, which is a potential game-changer. [ABSTRACT FROM AUTHOR]

Aims To assess levels of the calcium permeable transient receptor potential cation channel, subfamily melastatin, member 8 (TRPM8) in breast cancer molecular subtypes and to assess the consequences of TRPM8 pharmacological inhibition with AMTB (an inhibitor of TRPM8) on breast cancer cell lines. Materials and methods Cell viability and migration of breast cancer cells was determined using MTS assays and wound healing assays, respectively. RNA-Seq analysis of breast tumours and qPCR in breast cancer cell lines were used to assess mRNA levels of ion channels. Membrane potential assays were employed to assess the effects of AMTB against specific voltage gated sodium channels (Na V ). Key findings TRPM8 levels were significantly higher in breast cancers of the basal molecular subtype. AMTB decreased viable cell number in MDA-MB-231 and SK-BR-3 breast cancer cell lines (30 and 100 μM), and also reduced the migration of MDA-MB-231 cells (30 μM). However, these effects were independent of TRPM8, as no TRPM8 mRNA was detected in MDA-MB-231 cells. AMTB was identified as an inhibitor of Na V isoforms. Na V 1.1–1.9 were expressed in a number of breast cancer cell lines, with Na V 1.5 mRNA highest in MDA-MB-231 cells compared to the other breast cancer cell lines assessed. Significance TRPM8 levels may be elevated in basal breast cancers, however, TRPM8 expression appears to be lost in many breast cancer cell lines. Some of the effects of AMTB attributed to TRPM8 may be due to effects on Na V channels. [ABSTRACT FROM AUTHOR]

NRC researchers have recently employed computational tools to simulate airline passenger movement – primarily to examine the impact of different procedures on aircraft boarding times. It was felt that the modelling techniques could be improved by the inclusion of current, relevant and refined data on passenger movement. This article outlines a series of small-scale laboratory tests performed to help quantify individual passenger boarding and deplaning movement with and without the presence of luggage. Test subjects were monitored and video recorded while participants moved through a cabin section enabling observers to quantify the performance of specific micro-behaviours that formed the deplaning and boarding process. These tests were conducted at the National Research Council of Canada's prototype cabin research facility. The trials involved a total of 35 subjects who were each observed performing a series of 12 trials inside the cabin section. These trials were formed from the manipulation of three factors: seat pitch (29 in/31 in/33 in), luggage (present/absent), and instructions (continuous flow/discrete movements). During each trial, participants performed a series of micro-behaviours that included traversing the aisle/row, stowing/collecting under-seat bags, seat belt fastening and unfastening and adopting a brace position. In addition, two trials were conducted for each participant outside of the cabin facility to establish baseline straight line movement speeds with and without luggage. The study indicated that the impact of luggage and seat pitch had a notable, but complex, effect on performance and, more importantly, generated an array of data-sets for use in future simulation efforts. For instance, seat pitch appeared to have a more consistent impact when passenger movement was perpendicular to the seat row, as opposed to along the seat row where the impact was varied. Such data collection is necessary to advance empirical support for current and future simulation efforts. [ABSTRACT FROM AUTHOR]

A novel type of supramolecular aggregate, named a “nanosponge” was synthesized through the interaction of novel supramolecular building blocks with trigonal geometry. The cholesterol-(K/D) n DEVDGC) 3 -trimaleimide unit consists of a trigonal maleimide linker to which homopeptides (either K or D) of variable lengths (n = 5, 10, 15, 20) and a consensus sequence for executioner caspases (DEVDGC) are added via Michael addition. Upon mixing in aqueous buffer cholesterol-(K) n DEVDGC) 3 -trimaleimides and a 1:1 mixture of cholesterol-(K/D) n DEVDGC) 3 -trimaleimides form stable nanosponges, whereas cholesterol-(D) n DEVDGC) 3 -trimaleimide is unable to form supramolecular aggregates with itself. The structure of the novel nanosponges was investigated through explicit solvent and then coarse-grained molecular dynamics (MD) simulations. The nanosponges are between 80 nm and several micrometers in diameters and virtually non-toxic to monocyte/macrophage-like cells. [ABSTRACT FROM AUTHOR]

Although short acting acetyl cholinesterase inhibitors are used in colonic or small bowel pseudo-obstruction, their use in post-surgical gastroparesis is not clear. We demonstrate the successful use of neostigmine in a patient with resistant gastroparesis following distal gastrectomy. A 73-year-old male presented with features of gastric outflow obstruction 3 weeks following a distal gastrectomy. Prior to 3 weeks, he underwent an uneventful open distal gastrectomy for an incidentally detected low grade gastrointestinal stromal tumour (GIST) of the gastric antrum. An omega-loop isoperistaltic, 2-layer, posterior, retrocolic gastrojenunostomy was performed with a jejuno-jejunostomy. Abdominal ultrasonography was negative for intra-abdominal collections. Gastrograffin study and endoscopy ruled out an obstruction. A trial of prokinetics was unsuccessful with persistent nasogastric tube drain. Intravenous neostigmine was commenced with immediate symptomatic relief, reduction of abdominal distension and bowel evacuation without any cardiac adverse effects. At 6 months follow up, the patient was tolerating normal diet with no recurrence of symptoms. The management of post-surgical gastroparesis is challenging. Although various prokinetics are described for gastric motility disorders, the studies among post-gastrectomy patients with gastroparesis are limited. In our patient, the successful administration of neostigmine avoided the morbidity due to revision surgery. The use of neostigmine infusion was safe and effective for post-surgical gastroparesis after distal gastrectomy in our patient. To date, there are no trials investigating the place of neostigmine for resistant gastroparesis after gastric surgery and future studies are warranted prior to routine use in clinical practice. • The management of resistant post-surgical gastroparesis is challenging. • Neostigmine was safe and effective in relieving gastroparesis in our patient. • Further clinical research is needed before routine use in clinical practice. [ABSTRACT FROM AUTHOR]

A nanobiosensor for arginase detection was designed and synthesized. It features a central dopamine-coated iron/iron oxide nanoparticle to which sulfonated cyanine 7.0 is tethered via a stable amide bond. Cyanine 5.5 is linked to the N-terminal of the peptide sequence GRRRRRRRG. Arginine (R) reacts to ornithine (O) in the presence of arginase. Based on calibration with commercially obtained arginase II, the limit of detection (LOD) is picomolar. It is noteworthy that the nanobiosensor for arginase detection does not show a fluorescence increase when incubated with the enzyme NO-reductase, which also uses arginase as substrate, but is indicative of an inflammatory response by the host to cancer and infections. Arginase activity was determined in a syngeneic mouse model for aggressive breast cancer (4 T1 tumors in BALB/c mice). It was found that the arginase activity is systemically enhanced, but especially pronounced in the active tumor regions. [ABSTRACT FROM AUTHOR]

The ability to calculate the oil droplet size distribution (DSD) and its dynamic behavior in the water column is important in oil spill modeling. Breaking waves disperse oil from a surface slick into the water column as droplets of varying sizes. Oil droplets undergo further breakup and coalescence in the water column due to the turbulence. Available models simulate oil DSD based on empirical/equilibrium equations. However, the oil DSD evolution due to subsequent droplet breakup and coalescence in the water column can be best represented by a dynamic population model. This paper develops a phenomenological model to calculate the oil DSD in wave breaking conditions and ocean turbulence and is based on droplet breakup and coalescence. Its results are compared with data from laboratory experiments that include different oil types, different weathering times, and different breaking wave heights. The model comparisons showed a good agreement with experimental data. [ABSTRACT FROM AUTHOR]

This paper presents a study on the impact of underwater gas blowouts near the ocean surface, which has a greater relevance to assess Health, Safety, and Environmental risks. In this analysis the gas flux near the surface, reduction of bulk density, and gas surfacing area are studied for different scenarios. The simulations include a matrix of scenarios for different release depths, release rates, and initial bubble size distributions. The simulations are carried out using the MEGADEEP model, for a location in East China Sea. Significant changes in bulk density and gas surface flux near the surface are observed under different release conditions, which can pose a potential threat for cleanup and rescue operations. Furthermore, the effect of hydrate formation on gas surfacing is studied for much greater release depths. The type of outcomes of this study is important to conduct prior risk assessments and contingency planning for underwater gas blowouts. [ABSTRACT FROM AUTHOR]

• Rice husk biochar is used as a green supplement to produce alkali-activated slag. • Biochar increases the compressive strength of alkali-activated slag except at 1-day. • Biochar promotes the formation of hydration products. This research aimed at assessing the feasibility of activating biochar and ground granulated blast furnace slag (GGBS) combination using a blend of sodium carbonate and sodium hydroxide as the alkaline activator as a potential sustainable construction material. Taguchi Orthogonal experimental design was used to optimise the mix proportions considering three distinct biochar types (Rice husk biochar- (RB) and two sewage sludge biochar types), three biochar replacement levels (1, 2 and 5%) and three Na 2 O contents (6, 8 and 10%) as the parameters. The effect of biochar on the compressive strength, flowability and setting time was tested. The hydration mechanisms of biochar supplemented alkali-activated slag (AAS) were studied by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and 29Si nuclear magnetic resonance (NMR). In view of the overall performance in compressive strength, flow and setting time, the use of 2% RB with 10% Na 2 O content was identified to be the optimum combination. In contrast to the control mix, the optimum mix showed increment of compressive strength at 3-, 7-, 28- and 56-days of 16.5%, 13.5%, 7.4% and 12.2% respectively. Hydration analyses revealed that RB enhanced the formation of hydration products. Such improvements to the AAS product has potentially been introduced by the biochar's high-water absorption and retention property. [ABSTRACT FROM AUTHOR]

The process of formulation, revision and approval of port infrastructure tariffs is complex and involves different stakeholders. The extant literature focuses more on port pricing research but pays less attention to the practice of port infrastructure tariff setting. This paper aims to identify and analyses the influential factors in the port infrastructure tariff formulation process using survey data collected from 67 port authorities. Exploratory factor analysis (EFA) is first conducted before confirmatory factor analysis (CFA) is applied to analyse the latent factors underlying port infrastructure tariff setting. The analysis results suggested the four factors influential to infrastructure tariff practice, namely tariff policies, transparency, tariff regulation and stakeholder participation. The paper also presents the implications for port authorities, management and stakeholders. [ABSTRACT FROM AUTHOR]

A properly managed effective waste management programme increases the health and environmental quality of the country .This survey examines the status of Solid Waste Management household level in a peri-urban area (Kottawa in Colombo) in relation to the willingness of the people for the participation of an upgraded programme and the level of awareness of the people about the environmental and health hazards associated with disorganized management of solid waste. A pretested and self-administered questionnaire was used for primary data collection covering 50 households which were selected randomly. Data were analysed according to the descriptive statistics. The common waste types include food, paper, plastic, metal, glass and batteries. The rate of waste generation from more than 70% of the households exceeds 2 kg per day. 94% of the total waste collection was from the kitchen. Nearly 50% uses waste pits in their home gardens. Other methods of kitchen waste disposal were garbage truck collection (44%), burning (44%), composting (16%) and incineration (10%).66% of the households practice burning to dispose papers and cardboard. Disposal of non biodegradable waste such as glass, plastic, batteries and metal were done through a separate garbage truck. Waste separation at household level was practiced by 52% while 42% do not practice it. Compost bins were popular among 30% of the households. However, compost bins were unknown to 6%. Active participation for home composting was observed among 26%. Awareness about the environmental hazards caused by improper waste management was 100%. Only 2% of the respondents did not have much concern about the health impact of improper waste management. 54% of the household was unsatisfied with the prevailing waste management practices and 70% of them expect more involvement by the government to correct the problem. The results also showed that 26% of the households were not aware of waste recycling, reuse & reduction. However, 96% of the respondents agreed to co-operate & to participate for a proper waste management programme. Suggestions produced by the respondents to implement an effective waste management programme include composting (34%), efficient waste separation (14%), establishment of government owned waste collecting canters (28%), and provision of standard waste bins for household use under a subsidized programme and standard garbage trucks with a unique honking facility 12%. [ABSTRACT FROM AUTHOR]

Previous models on simulating gas releases in deepwater were not focused on the dissolved component and its impact on water quality. This paper presents a new model developed for simulating the transport/spread of dissolved methane from an underwater release and its impact on dissolved oxygen in ambient water. Methane dissolves into ambient water from gas phase, direct from hydrate phase, and from dissociating hydrates formed earlier. Dissolved methane affects the dissolved oxygen levels in ambient water due to microbial interaction and possible direct absorption of oxygen into methane bubbles. We use new model simulations of Deepspill field experiments to compare with instantaneous profiles which were unpublished until now. The comparisons are very good with a short time lag, but are within the acceptable discrepancy for models for emergency response and contingency planning. Scenario simulations show the effect on dissolved oxygen due to different methane release situations. [ABSTRACT FROM AUTHOR]