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The surgical reconstruction of severe corneal disease is a common and crucial component of the clinical practice of veterinary ophthalmology. The first part of the present review described procedures that utilize autogenous ocular tissues, homologous donor tissues, and heterologous donor tissues in dogs, while the second part reviewed the use of biomaterials and keratoprosthetics in this species. This third part is dedicated to the review of the use of corneal sutures including suture type and suture pattern in corneal reconstruction of small animals including dogs and cats. The review also focused on the way studies report postoperative ocular discomfort/pain and how this is treated. Lastly, the author briefly presents the simple but effective techniques available to bury corneal knots for corneal reconstructive surgery in small animal patients, such as the "tugging" and "deep-superficial-superficial-deep" methods for simple interrupted sutures, and the adaptation of the latter for simple continuous sutures., (© 2024 American College of Veterinary Ophthalmologists.)

Corneal reconstruction is a key part of veterinary ophthalmic practice and numerous reconstructive techniques have been described for use in small animals in the peer-reviewed veterinary literature written in English. Despite the evidence accrued over the last six decades in over 40 clinical articles and numerous other publications on ocular surface health, several key areas require further study. The comparison between studies is difficult due to elements that go beyond common factors, such as the indication for surgery, the reconstructive technique preferred by the surgeon or the availability of reconstructive materials. However, the differences in reporting style adopted by different authors between similar studies and the lack of data found in retrospective studies add to this complexity. The present review is divided into three parts. One covers the use of autologous materials for reconstruction and corneal transplants, as well as corneal clarity. A second part focuses on biomaterials and keratoprosthetics, while the third part focuses on the use of corneal sutures and report of ocular discomfort/pain in the veterinary literature. The review focuses on the main findings of each reconstruction technique. It aims to identify areas where key information about common procedures is missing so that general guidelines may be provided for the planning of patient record keeping and future retrospective or prospective studies, while it also aims to highlight the presence of knowledge gaps that deserve further attention., (© 2024 American College of Veterinary Ophthalmologists.)

Wind energy has emerged as a promising renewable energy source and wind turbine technology has developed rapidly in recent years. Improved wind turbine performance depends heavily on the design and optimization of wind blades. This work offers a critical evaluation of the state of the art in the field of numerical modelling and simulation analysis, which have become crucial for the design and optimization of wind blades. The evaluation of the literature includes considerable research on the application of numerical methods for the structural and aerodynamic performance of wind blades under various operating situations, as well as for analysis and optimization of wind blades. The article illustrates how numerical techniques can be used to analyse wind blade performance and maximize design efficiency. The study of blade performance under various wind conditions has also been made possible through the use of simulation analysis, thus enhancing the efficiency and dependability of wind turbines. Improvements in wind turbine efficiency and dependability, and ultimately the move towards a more sustainable energy future, will be greatly helpful for the development of numerical modelling and simulation techniques. [ABSTRACT FROM AUTHOR]

Accurate and up-to-date Geographic Information System (GIS) and Techno Economic (TE) tools are pertinent to helping to develop the renewable energy sector. This paper reviews the state of the art in existing GIS and TE tools for renewable energy and proposes a methodology to develop a coupled GIS-TE software tool that is geared specifically to Marine Renewable Energy (MRE) applications and bespoke to Irish and Western UK waters. Methods for approaching GIS and TE analysis within existing tools for renewable energy are presented and compared. Many existing tools of this nature have some interesting functionalities, but most are unsuitable for MRE; are limited by a lack of information on both the technology and the site; and focus solely either on GIS or TE aspects of analysis. Additionally, almost all of those with a TE focus are not open access. The proposed tool aims to incorporate increased resolution and site relevance of resource data; the most up-to-date geospatial data for site selection; and will provide site specific TE indicators and recommendations for contemporary MRE devices. The result will be the development of an open-access GIS-TE software tool for MRE. [ABSTRACT FROM AUTHOR]

This study uses novel evolutionary algorithms and computational techniques to analyze wind potential on flat, complex coastal, and offshore sites utilizing mast as well as remote sensing data. The wind data were recorded using remote sensing technique and conventional technique. The optimum Weibull parameters are estimated using nine methods. The genetic algorithm, particle swarm optimization, and TLBO algorithms are compared and evaluated. The goodness of fit test, such as root mean square error test (RMSE), mean absolute percentage error (MAPE), coefficient of determination (R2), and chi-square test (X2), is used to evaluate the accuracy of the selected methods. Parameter estimates are used to compute wind densities. The TLBO and PSO algorithms outperformed genetic algorithms in terms of efficiency. This research compares remote sensing measurements to cup anemometer measurements. [ABSTRACT FROM AUTHOR]

Both mixed λ3-iodoarenes and λ3-iodoarenes possessing –OTf ligands are coveted for their enhanced reactivities. Here we describe the synthesis, reactivity, and comprehensive characterisation of two new ArI(OTf)(X) species, a class of compound that were previously only invoked as reactive intermediates where X = Cl, F and their divergent reactivity with aryl substrates. A new catalytic system for electrophilic chlorination of deactivated arenes using Cl2 as the chlorine source and ArI/HOTf as the catalyst is also described. [ABSTRACT FROM AUTHOR]

A major challenge to the emergence and establishment of new energy technologies such as ocean wave energy is the insufficient or nonexistent database for estimating resource potential. Despite having an extensive coastline, wave energy sources are yet to be developed in India. Hence, the main objective of this study is to identify the potential sites and assess the technical and economic feasibility of harnessing wave energy along the Indian coast. Three hotspots are identified in three coastal regions (east, south and west) based on optimum hotspot index and depth constrain criterion using 19 years of high-resolution wave hindcast. Results indicate that the theoretical potential of location along the west coast (12 kW/m) is highest as compared to a hotspot near the south (8 kW/m) and east coast (6 kW/m). The technical potential and cost of electricity generation at hotspot locations are estimated and compared using four different wave energy converters (WECs): Wavedragon, Pelamis, Oceantec, and Aquabuoy. Oceantec, among all WECs, generates more power (40–57 GWh) and attain a maximum capacity factor (22–31%) as well as the most cost-effective WEC with the lowest Levelized Cost of Energy (LCOE) ranging from 354 to 505 €/MWh at all hotspots. Economic sensitivity analysis reveals that interest rate and operation and maintenance costs are the most and least sensitive parameters, respectively. Outcomes of the present study will contribute to reducing the barriers to the current knowledge of wave energy resources in India. [ABSTRACT FROM AUTHOR]

A study on the kinetics of the activation of PhICl2 using catalytic chloride or pyridine in electrophilic chlorination of arenes has been carried out. The results indicate that both catalysts induce the release of Cl2 from PhICl2 and that the Cl2 is the active reagent for chlorination in these reactions. [ABSTRACT FROM AUTHOR]

With global warming and the depletion of fossil energy sources, renewable energy is gradually replacing non-renewable energy as the main energy in the future. As one of the fastest growing renewable energy sources, the safety and reliability of wind energy have been paid more and more attention. The size of modern wind turbines is becoming larger and larger. As the main component of wind turbines to capture energy, the blade is often damaged by various complex environments and irregular loads. Therefore, the health monitoring and damage identification of wind turbine blades have become a main research focus. At present, in addition to the overview of various detection methods of wind turbine blades, there is a lack of comprehensive classifications and overviews of the main damage types, damage-generation mechanisms, and basic principles of the damage-detection technology of wind turbine blades. In this paper, firstly, the common fault types of wind turbine blades, such as trailing edge cracking, lightning strike, leading edge corrosion pollution, icing, and delamination, as well as their generation mechanism, are comprehensively analyzed. Then, the basic principles and the latest research progress of the current main detection technologies, such as vision, ultrasonic, thermal imaging, vibration, acoustic emission, and so on, are comprehensively reviewed. The advantages and limitations of the various detection technologies for practical application are summarized. Finally, through a comparative analysis of the various damage-detection technologies, we try to find potential future research directions, and draw conclusions. This paper will provide a reference for understanding the mechanism behind the main damage types and the damage-detection methods of wind turbine blades. It has important reference value for further promoting practical research of wind turbine blade damage-detection technology and grasping this research direction. [ABSTRACT FROM AUTHOR]

Purpose: The assessment of the economic feasibility of floating offshore wind farms (FOWFs) plays an important role in the future possible spreading of this challenging technology in the wind power industry. The use of specific economic analyses is fundamental to point out the potential of FOWFs and to sustain their technical value. Within this topic, the implementation of the FOWF life cycle cost model and producibility analysis in a geographic information system is developed, with the aim of carrying out a feasibility analysis at the territorial scale, for different types of floater. Moreover, a simplified model for a quick life cycle cost assessment is proposed and calibrated. Methods: The available cost model is first validated comparing the costs of FOWFs based on different floaters (Semi-Submersible Platform—SSP, Spar Buoy—SB and Tension Leg Platform—TLP) with corresponding results available in the literature. Then, it is implemented in QGIS to be used for territorial-scale analyses and sensitivity analyses of the cost parameters. A feasibility analysis is developed through the main financial parameters. Finally, the results are then used to calibrate a simplified version of the cost model that depends on three main parameters, namely distance to shore, distance from the port of operation and bathymetry. Results and discussion: The FOWF cost values are found to be in good agreement with those coming from analytical methods similar to the one from the authors. However, some discrepancies with those based on average costs are observed. Then, the results of the sensitivity analysis are presented as life cycle cost maps, giving an overall picture of the variation of the total cost of FOWF installations on a reference domain. The results show that among the three types of floaters considered here, the SSP proved to be the most promising one, giving lower costs than the SB and the TLP. Moreover, a good agreement between the results in terms of total cost of FOWFs calculated with the analytical and simplified models for SSPs, SBs and TLPs is observed. Finally, the feasibility analysis showed that the financial parameters are more influenced by the wind speed than by the cost of the farm. Conclusions: The paper aims to provide guidance on how to carry out feasibility analyses of a specific site for FOWF installation, thus supporting decision-making procedures. The approach and the results presented here are meant for use in the early stage of the decision-making process, as a tool for the assessment of the economic feasibility of FOWFs installation. [ABSTRACT FROM AUTHOR]

An overview on the assessment of wind energy technology adoption and the extent of penetration of wind energy as an alternative energy source in different regions of the world is presented. A global scenario of Asia, Americas, Europe and Gulf States were reviewed and particular attention was centred on the successes of wind energy in Africa. The four major drivers—global warming, natural disasters, crisis and agreements—that have affected growth of wind energy technology were discussed. The economics of wind energy technology particularly as a grid connected solution was reviewed, challenges in the roll-out of wind energy technology were also highlighted. Finally, the prospects and future of wind energy as part of the overall energy mix was reviewed. [ABSTRACT FROM AUTHOR]

Summary: The current study focuses on early prediction of structural failure of a composite wind turbine blade (WTB) using acoustic emission (AE) and strain measurement. The structural response of a 14.3‐m blade with embedded artificial defects is investigated under fatigue loading in flapwise direction. The fatigue loading is realized in several successive portions until structural failure. Strain and acoustic emission signals from each portion are recorded. The goal is to explore damage‐sensitive features (DSFs) derived from acoustic emission and strain signals that would be suitable for early indication of blade failure under fatigue. These features include modal characteristics of strain time history, such as natural frequencies, damping ratios, and modal amplitudes. Acoustic emission features explored in this study comprise average frequency centroids based on an amplitude and absolute energy and gradients of cumulative energy curves. Changes of these features before failure relative to the previous loading portion are calculated and compared among different sensor locations with a twofold goal—firstly, to find the features that are the most sensitive to damage accumulation and, secondly, to find a location with the largest relative changes, thus enabling damage localization. The results show that strain and AE signals are correlated well in terms of pinpointing to a location of the largest aggregation of defects. This study gives recommendations of the most efficient feature combination of different measurements for reliable structural health monitoring of wind turbine blades. [ABSTRACT FROM AUTHOR]

Objectives: Report of prevalence and type of ocular disease in a captive population of nondomestic felids. Methods: Medical records of 202 cats from 1993 to 2018 were reviewed. Species, age at diagnosis, sex, ocular examination abnormalities, systemic/physical examination abnormalities, type of examination (visual, sedated, or anesthetized), ocular structures affected, other diagnostics, therapy, and resolution of ocular disease were recorded. Results: A total of 202 nondomestic felids including 18 different species (bobcat, caracal, cougar, Fishing cat, Geoffroy's cat, jaguar, jungle cat, leopard, leopard cat, liger, lion, lynx, ocelot, Sand cat, Savannah cat, serval, snow leopard, and tiger) from a rescue facility were evaluated. Forty‐six ocular lesions were diagnosed in 33 (16.3%) cats from 8 different species (bobcat, caracal, cougar, leopard, lion, ocelot, serval, and tiger) with a mean age of 16 ± 5.9 years at time of diagnosis. Ocular lesions included corneal disease (37%) (ulcerations, perforations, keratitis, corneal scars), cataracts (23.9%), hyphema (8.7%), lens luxation (6.5%), retinal detachment (6.5%), uveitis (4.3%), conjunctival disease (4.3%), retinal degeneration (2.1%), glaucoma (2.1%), and optic neuritis (2.1%). Therapies included medical (topical antibiotics, anti‐inflammatories, serum, etc.) and/or surgical management (enucleation, intracapsular lens extraction, corneoconjunctival transposition, and corneal burr debridement). Conclusions: To the authors' knowledge, this is the first report of the prevalence of ocular disease in a population of captive nondomestic felids. It is difficult to diagnose and treat ocular disease in nondomestic cats due to challenges related to handling, diagnostics, and therapeutics in nondomestic species. Ocular disease seen in this population is similar to that found in domestic cat populations. [ABSTRACT FROM AUTHOR]

Objective: To describe the use of multidirectional corneoconjunctival transposition (CCT) as a surgical treatment for large keratomalacia., Method: A prospective study including dogs and cats initially presenting with keratomalacia larger than 6 × 6 mm and affecting more than half of the corneal thickness. Signalment, concurrent eye diseases, ulcer size, bacterial culture and susceptibility testing results, follow-up, and outcome were recorded. The surgery consisted of harvesting of two or three opposite corneoconjunctival grafts, after removal of the malacic tissue using a square-edge keratectomy. The medical treatment consisted of administration of topical and systemic antibiotics, topical atropine, and N-acetylcysteine. Follow-up examinations were performed at D7, D14, D21, and D28, and then at various time points. The corneal clarity score (CCS) was recorded upon completion of the follow-up period., Results: Seven dogs and five cats were included. Brachycephalic dogs were overrepresented, with no breed predisposition in cats. Concurrent eye diseases were corneal pigmentation in three dogs, hypopyon in two dogs, nictitating membrane wound in one dog, and corneal perforation in one cat. The size of the keratomalacia ranged from 6 × 6 to 9.5 × 11.5 mm. The short-term complications were suture dehiscence (two of 12) and progression of the keratomalacia (one of 12). The long-term complications were corneal pigmentation (10 of 12), corneal epithelial inclusion cyst (two of 12), and marginal synechiae (one of 12). All animals were sighted at the last follow-up. The median CCS was G3 (range G2-G4)., Conclusion: Multidirectional CCT is an effective surgical treatment for large keratomalacia in dogs and cats., (© 2023 American College of Veterinary Ophthalmologists.)