23 research outputs found

    Safe navigation in the Arctic

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    Evaluation of the Polar Code in different environments and for different maritime activities in the two polar regions

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    Because of the decrease in sea ice coverage, maritime activities in the polar regions have increased steadily over the years and several issues related to maritime activities have arisen. It is essential to understand these challenges because they could have serious political, environmental, and economic consequences. Although there are significant geographical and legal differences and differences in the types of activities between the Arctic and the Antarctic, a single International Maritime Organization Polar Code covers both regions. In this analysis, changes in polar regions are introduced, and the differences between the Arctic and Antarctic are discussed. The differences in maritime activities in the two polar regions are then discussed, and the Polar Code is evaluated in terms of these differences

    Delivering sustained, coordinated and integrated observations of the Southern Ocean for global impact

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    The Southern Ocean is disproportionately important in its effect on the Earth system, impacting climatic, biogeochemical, and ecological systems, which makes recent observed changes to this system cause for global concern. The enhanced understanding and improvements in predictive skill needed for understanding and projecting future states of the Southern Ocean require sustained observations. Over the last decade, the Southern Ocean Observing System (SOOS) has established networks for enhancing regional coordination and research community groups to advance development of observing system capabilities. These networks support delivery of the SOOS 20-year vision, which is to develop a circumpolar system that ensures time series of key variables, and delivers the greatest impact from data to all key end-users. Although the Southern Ocean remains one of the least-observed ocean regions, enhanced international coordination and advances in autonomous platforms have resulted in progress toward sustained observations of this region. Since 2009, the Southern Ocean community has deployed over 5700 observational platforms south of 40°S. Large-scale, multi-year or sustained, multidisciplinary efforts have been supported and are now delivering observations of essential variables at space and time scales that enable assessment of changes being observed in Southern Ocean systems. The improved observational coverage, however, is predominantly for the open ocean, encompasses the summer, consists of primarily physical oceanographic variables, and covers surface to 2000 m. Significant gaps remain in observations of the ice-impacted ocean, the sea ice, depths >2000 m, the air-ocean-ice interface, biogeochemical and biological variables, and for seasons other than summer. Addressing these data gaps in a sustained way requires parallel advances in coordination networks, cyberinfrastructure and data management tools, observational platform and sensor technology, two-way platform interrogation and data-transmission technologies, modeling frameworks, intercalibration experiments, and development of internationally agreed sampling standards and requirements of key variables. This paper presents a community statement on the major scientific and observational progress of the last decade, and importantly, an assessment of key priorities for the coming decade, toward achieving the SOOS vision and delivering essential data to all end-users.Fil: Newman, Louise. University of Tasmania; AustraliaFil: Heil, Petra. Australian Antarctic Division; Australia. Antarctic Climate And Ecosystems Cooperative Research Centre; AustraliaFil: Trebilco, Rowan. Australian Antarctic Division; Australia. Antarctic Climate And Ecosystems Cooperative Research Centre; AustraliaFil: Katsumata, Katsuro. Japan Agency For Marine earth Science And Technology; JapónFil: Constable, Andrew J.. Antarctic Climate And Ecosystems Cooperative Research Centre; Australia. Australian Antarctic Division; AustraliaFil: Wijk, Esmee van. Commonwealth Scientific And Industrial Research Organization; Australia. Antarctic Climate And Ecosystems Cooperative Research Centre; AustraliaFil: Assmann, Karen. University Goteborg; SueciaFil: Beja, Joana. British Oceanographic Data Centre; AustraliaFil: Bricher, Phillippa. University of Tasmania; AustraliaFil: Coleman, Richard. University of Tasmania; AustraliaFil: Costa, Daniel. University of California; Estados UnidosFil: Diggs, Steve. University of California; Estados UnidosFil: Farneti, Riccardo. The Abdus Salam; Italia. The Abdus Salam. International Centre for Theoretical Physics; ItaliaFil: Fawcett, Sarah. University of Cape Town; SudáfricaFil: Gille, Sarah. University of California; Estados UnidosFil: Hendry, Katharine R.. University of Bristol; Reino UnidoFil: Henley, Sian F.. University of Edinburgh; Reino UnidoFil: Hofmann, Eileen. Old Dominion University; Estados UnidosFil: Maksym, Ted. University of California; Estados UnidosFil: Mazloff, Matthew. University of California; Estados UnidosFil: Meijers, Andrew J.. British Antartic Survey; Reino UnidoFil: Meredith, Michael. British Antartic Survey; Reino UnidoFil: Moreau, Sebastien. Norwegian Polar Institute; NoruegaFil: Ozsoy, Burcu. Istanbul Teknik Üniversitesi; TurquíaFil: Robertson, Robin. Xiamen University; ChinaFil: Schloss, Irene Ruth. Universidad Nacional de Tierra del Fuego; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; ArgentinaFil: Schofield, Oscar. State University of New Jersey; Estados UnidosFil: Shi, Jiuxin. Ocean University Of China; ChinaFil: Sikes, Elisabeth L.. State University of New Jersey; Estados UnidosFil: Smith, Inga J.. University of Otago; Nueva Zeland

    First observations of emperor penguins on Horseshoe Island, Antarctica

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    This note reports observations of two moulting emperor penguins (Aptenodytes forsteri) on Horseshoe Island, West Antarctica, during the Seventh Turkish Antarctic Expedition in February 2023. This is the first time this species has been documented on this island. Emperor penguins largely depend on fast-ice to breed and moult. The Antarctic Peninsula hosts few emperor penguin colonies. Horseshoe Island has become one of the northernmost points along the western Antarctic Peninsula where emperor penguins are documented to moult

    Design of Sustained Release Tablet Formulations of Alfuzosin HCl by means of Neuro-Fuzzy Logic

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    Fuzzy logic is a problem-solving technique which derives its power from its ability to draw conclusions and generate responses based on vague, ambiguous, incomplete and imprecise information. This study is intended to design sustained release formulation of alfuzosin HCl by means of Neuro-Fuzzy logic. For the preparation of sustained release tablets of alfuzosin HCl, the selected parameters were as polymer type and concentration, tablet compression pressure force and concentration of lubricant. Physical and chemical tests of the tablets and commercial tablets were performed. The results of these tests and were installed on to the Form Rules V3.32 Neuro-Fuzzy logic software program. It was requested to assess and determine the most similar formulation to the reference product from logic software program. The compatibility of the program-recommended formulation was confirmed with dissolution studies using similarity factor

    Quetiapine Fumarate Extended-release Tablet Formulation Design Using Artificial Neural Networks

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    Objectives: This design study was implemented within the scope of the quality by design approach, which included the "International Conference on Harmonization" guidelines. We evaluated the quality of a modified-release tablet formulation of quetiapine fumarate, which was designed using artificial neural networks (ANN), and determined a new formulation that was similar to the reference product

    Mapping of Glaciers on Horseshoe Island, Antarctic Peninsula, with Deep Learning Based on High-Resolution Orthophoto

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    Antarctica plays a key role in the hydrological cycle of the Earth’s climate system, with an ice sheet that is the largest block of ice that reserves Earth’s 90% of total ice volume and 70% of fresh water. Furthermore, the sustainability of the region is an important concern due to the challenges posed by melting glaciers that preserve the Earth’s heat balance by interacting with the Southern Ocean. Therefore, the monitoring of glaciers based on advanced deep learning approaches offers vital outcomes that are of great importance in revealing the effects of global warming. In this study, recent deep learning approaches were investigated in terms of their accuracy for the segmentation of glacier landforms in the Antarctic Peninsula. For this purpose, high-resolution orthophotos were generated based on UAV photogrammetry within the Sixth Turkish Antarctic Expedition in 2022. Segformer, DeepLabv3+ and K-Net deep learning methods were comparatively analyzed in terms of their accuracy. The results showed that K-Net provided efficient results with 99.62% accuracy, 99.58% intersection over union, 99.82% precision, 99.76% recall and 99.79% F1-score. Visual inspections also revealed that K-Net was able to preserve the fine details around the edges of the glaciers. Our proposed deep-learning-based method provides an accurate and sustainable solution for automatic glacier segmentation and monitoring

    Modified Tension Band Wiring Technique For Olecranon Fractures: Where And How Should The K-Wires Be Inserted To Avoid Articular Penetration?

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    Objective: Articular penetration of K-wires is a possible complication of the modified tension band wiring technique. However, there is no clear information or evidence regarding the entry point or introduction angle for K-wires to avoid this complication. The aim of this experimental study was to evaluate the effect of varying K-wire insertion points and angles on the risk for articular penetration during modified tension band wiring for olecranon fractures. Methods: All anatomical measurements were made on 50 cadaveric ulnas, and all other measurements were performed on exact foam replications of the 50 cadaveric ulnas. Morphometric measurements, including olecranon height and heights of the central, radial and ulnar facets of the semilunar notch, were taken. In the sagittal plane, articular angle and tubercle angle were measured. Two 1.6-mm parallel K-wires were inserted from 0, 5 and 8 mm anterior to the dorsal cortex of the olecranon process at angles of 20 degrees and 30 degrees K-wire articular penetration was evaluated both visually and radiographically. Results: The mean central, radial and ulnar heights of the semilunar notch were 17.3 mm (14.7-20.0), 16.2 mm (12.0-21.0) and 15.8 mm (13.30-20.5), respectively. We observed no articular penetration at the 0-mm level at 20 degrees and 30 degrees (0 mm 20 degrees and 0 mm 30 degrees, respectively) or at 5 mm 20 degrees. At 8 mm 30 degrees wire introduction, more than 64% articular penetration was observed on either facet. The sequence from least to most likely to cause articular penetration was: 0 mm = 5 mm 20 degrees > 5 mm 30 degrees = 8 mm 20 inverted perpendicular > 8 mm 30 degrees. The radial height of the semilunar notch was negatively correlated to the risk of articular penetration, when the wire was introduced at 8 mm 30 degrees, 8 mm 20 degrees and 5 mm 30 degrees (all p <0.047). There were poor correlations between radiological and direct observational assessments, particularly for 8 mm 20 degrees and 5 mm 30 degrees. The frequency of intra-articular positioning for those observed to be radiologically extra-articular was 4/28 (14.3%) for 8 mm 30 degrees, 4/7 (57.1%) for 8 mm 20 degrees and 5/6 (83.3%) for 5 mm 30 degrees. Conclusion: When applying the modified tension band wiring technique to prevent articular penetration, K-wires should be inserted in the first 5 mm from dorsal cortex of the olecranon process at a maximum angle of 20 degrees. Moreover, if the wires are required to be inserted more anteriorly because of the anatomical configuration of the fracture, they should be inserted at a shallow angle in the sagittal plane in relation to the proximal cortex of the ulna.WoSScopu

    Product transfer from lab-scale to pilot-scale of quetiapine fumarate orodispersible films using quality by design approach

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    In this study, transfer from lab-scale non-continuous production to pilot-scale continuous production of orodispersible films was provided using solvent casting method under the framework of quality by design. Non-continuous production was carried out with petri dishes and continuous production was carried out with a coating machine. Films containing hydroxypropyl methylcellulose E5 as film forming polymer, polyethylene glycol 400 and propylene glycol as plasticizers, quetiapine fumarate as drug were formulated. Viscosity of the polymer dispersions, weight, thickness and disintegration time of the films were compared for the transfer of production. pH, moisture content, mechanical properties, folding endurance, uniformity of dosage units, dissolution, stability studies were also performed in pilot-scale orodispersible films. Finally, cytotoxicity studies were performed to determine cell viability. The study showed the possibility of producing F2-p-65/70 (pilot-scale film formulation containing 10 mg propylene glycol, dried at 65 degrees C and 70 degrees C) and F4-p-65/70 (pilot-scale film formulation containing 15 mg propylene glycol, dried at 65 degrees C and 70 degrees C), as the most suitable for further studies. Thus, a promising improvement has been achieved for schizophrenic patients by the production of quetiapine fumarate loaded orodispersible films and the process of scale-up in films has been demonstrated

    Hydrogen and poly-beta-hydroxybutyric acid production at various acetate concentrations using Rhodobacter capsulatus DSM 1710

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    In the present study, Rhodobacter capsulatus DSM 1710 was cultured in media having various concentrations of acetate (10-65 mM) to investigate simultaneous production of hydrogen and PHB. The highest cumulative hydrogen productions were observed using 50 mM (11.7 mmol H-2) and 65 mM (11.4 mmol H-2) acetate. However, molar productivity values were higher at 25 mM (0.50 mmol/Lc.h) and 50 mM (0.44 mmol/Lc.h) compared to 65 mM (0.35 mmol/Lc.h). Furthermore, the highest PHB production (234.7 mg/L) was attained using 65 mM acetate. At molecular level, the expressions of nifD and phaC genes were analyzed by reverse transcription-polymerase chain reaction using specifically designed tagged primers. Increasing acetate concentrations resulted in an increase in nifD and phaC expressions. Accordingly, the highest transcription levels were obtained at 65 mM acetate. The kinetic studies on hydrogen production and acetate consumption showed that hydrogen production data was in agreement with the Modified Gompertz Model and acetate was consumed through first order kinetics. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved
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