Adopting multiview pixel mapping for enhancing quality of holoscopic 3D scene in parallax barriers based holoscopic 3D displays

The Autostereoscopic multiview 3D Display is robustly developed and widely available in commercial markets. Excellent improvements are made using pixel mapping techniques and achieved an acceptable 3D resolution with balanced pixel aspect ratio in lens array technology. This paper proposes adopting multiview pixel mapping for enhancing quality constructed holoscopic 3D scene in parallax barriers based holoscopic 3D displays achieving great results. The Holoscopic imaging technology mimics the imaging system of insects, such as the fly, utilizing a single camera, equipped with a large number of micro-lenses, to capture a scene, offering rich parallax information and enhanced 3D feeling without the need of wearing specific eyewear. In addition pixel mapping and holoscopic 3D rendering tools are developed including a custom built holoscopic 3D displays to test the proposed method and carry out a like-to-like comparison.This work has been supported by European Commission under Grant FP7-ICT-2009-4 (3DVIVANT). The authors wish to ex-press their gratitude and thanks for the support given throughout the project

Moiré-Free Full Parallax Holoscopic 3D Display based on Cross-Lenticular

Holoscopic imaging also known as Integral imaging is a promising 3D solution that mimics the imaging system of insects, such as the fly, utilizing a single camera, equipped with a large number of microlens array, to capture a scene, offering rich parallax information and enhanced 3D feeling without the need of wearing specific eyewear. Recently, initial developments are made for designing a full parallax holoscopic 3D display using parallax barriers which suffers low lighting throughput as the constructed 3D scene is a rather dim. Also a first attempt was made designing an omnidirectional holoscopic 3D display using cross-lenticular which introduces moiré effect. This paper proposes and presents a moiré-free full parallax holoscopic 3D display which offers omnidirectional motion parallax and complete 3D depth

Orthodontic Bonding: Review of the Literature

Background. Patients seeking orthodontic treatment are increasing, and clinicians often have to place brackets on various surfaces aside from enamel. It is crucial to know what materials or instruments are required to bond brackets to each surface. Objective. This study aims to serve as a clinical guideline for the safest and most effective approaches taken to condition various surfaces for bonding to orthodontic brackets and provide background knowledge on the subject. Materials and Methods. PubMed and EBSCO databases were searched, along with the use of Google Scholar search engine, to obtain relevant articles published in English in peer-reviewed journals, from 1955 to 2020. Keywords used were Shear bond strength; Orthodontic bracket; Base design; Etching; Sandblasting; Laser; Conditioning; Enamel; Ceramic; Porcelain; Gold; Amalgam; Composite. Conclusion. Even though orthophosphoric acid is the most widely used enamel conditioning agent, laser etching should be considered to avoid enamel decalcification. Hydrofluoric acid is the current standard for ceramic conditioning; however, its use intraorally should be minimized due to its toxicity. Orthophosphoric acid, CoJet-Sand air abrasion, and laser etching are viable alternatives for conditioning ceramic. Monobond Etch & Prime is toxic and should not be used intraorally. Composite can be conditioned by bur roughening, and the use of ceramic brackets is recommended. Amalgam and gold surfaces can be conditioned adequately by air abrasion. Despite the claims of many authors, the maximum shear forces that orthodontic brackets are subjected to are not 6–8 mega pascal (MPa). Further investigation is required in that regard. More in vivo studies need to be performed to confirm the in vitro results

Dynamic hyperlinker for 3D content search and retrieval

Recently, 3D display technology, and content preparation and creation tools have been under vigorous development. Consequently, they are also widely adopted by home and professional users. 3D digital repositories are increasing and becoming available ubiquitously. However, there is not yet a single 3D content search and retrieval platform. In this paper, we propose and present the development of a novel approach for 3D content search and retrieval which is called Dynamic hyperlinker for 3D content search and retrieval. It advances 3D multimedia navigability and searchability by creating dynamic links for selectable and clickable objects in the scene while the 3D video clip is being replayed. The proposed system involves 3D video processing, such as detecting/tracking clickable objects, annotating objects, and metadata engineering. Such system attracts the attention from both home and professional users such as broadcasters and digital content providers. The experiment is conducted on Holoscopic 3D images “also known as integral images”

Holoscopic 3D image rendering for autostereoscopic multiview 3D display

The Autostereoscopic Multiview 3D Display is robustly developed and widely adopted by both home and professional users however Multiview 3D content generation remains a great challenge. This paper proposes a novel method for Multiview 3D content generation and it describes the necessary steps for Holoscopic 3D image rendering for autostereoscopic Multiview 3D display. The Holoscopic imaging technology mimics the imaging system of insects, such as the fly, utilizing a single camera, equipped with a large number of micro-lenses, to capture a scene, offering rich parallax information and enhanced 3D feeling without the need of wearing specific eyewear. In addition a 3D pixel mapping/conversion algorithm has been developed that is supported by the Multiview 3D display

Carbon dioxide removal and net zero emissions in Africa: an integrated assessment modelling based on three different land-based negative emission solutions

As the remaining carbon budget for limiting warming to 1.5 °C rapidly diminishes, it is clear that, besides decarbonization, the world will need to remove 100–1000 GtCO _2 from the atmosphere by the end of the century. Yet, Africa, where many carbon removal schemes are planned, remains a ‘blindspot’ in existing studies. There is limited understanding of the trade-offs and synergies associated with carbon removal within Africa’s energy-land-water system. To address this research gap, we model a stylized net-zero emissions (NZEs) in Africa by 2050, with focus on three land-based biological carbon removal approaches: afforestation/reforestation (AR), bioenergy with carbon capture and storage (BECCS), and biochar. We find that by 2050, the total gross carbon removal is projected to reach 1.2 GtCO _2 yr ^−1 when all three carbon removal approaches are available, and 0.5 GtCO _2 yr ^−1 when Africa relies solely on AR. Pursuing NZE with only AR or AR alongside biochar in Africa would be the most expensive mitigation option but they lead to the lowest residual fossil fuel and industry CO _2 emissions. An NZE by 2050 in Africa could reduce cropland by 30%–40% from 2020 to 2050, depending on the carbon dioxide removal deployment strategy adopted. Southern Africa would be particularly affected, facing significant challenges in balancing food security with climate goals. The highest increase in staple food prices will occur under AR only, while the availability of AR-BECCS-biochar produces the lowest rise in staple food prices. Our findings highlight the need for balanced and region-specific carbon dioxide removal strategies to ensure climate and other sustainability goals are met

Hydrochemistry of Surface and Groundwater in Parts of Birnin Kebbi Northwestern Nigeria

A hydro-chemical investigation of drinking water sources in Birnin Kebbi Old Town and its environs, in northwestern Nigeria, was carried out to determine the potability and suitability of the groundwater for domestic and agricultural uses. Twenty-three water samples were collected from these communities, and their physical and chemical parameters, such as electrical conductivity, total dissolved solids, pH, and temperature, were evaluated. Both the chemical and heavy metal analyses were conducted at the Multi-User Laboratory, Usmanu Danfodiyo University, Sokoto. The results obtained indicated that physical parameters like TDS and EC and chemical parameters like Mg2+, Ca2+ and HCO32- are high, while Cr2+, Fe2+, Ni, and Pb2+ have values that are below the NSDWQ recommended limits. While Na2+, Cu2+, Cl-, and NO3- have values far below the NSDWQ set limit, The Schoeller and Piper diagrams show the dominant water type in the study area to be Ca-Mg-HCO3. However, the Gibbs plot shows the dominant source of the water to be the precipitation domain due to the dissolution of carbonate rocks, while the Wilcox diagram shows that all the water samples in the study area have low salinity. Application of Nemerow’s pollution index method shows that the majority of the sampling locations displayed high NPI values, especially for Ni2+ and Pb2+. The NPI Ni2+ values for eleven (11) out of twenty-three samples, making up 47.83%, have NPI values that range from 7.53 to 90.01, making them unsuitable for drinking purposes. The NPI values for Pb2+ for six (6) samples, making up about 26.09%, have high NPI values that range from 36.37 to 172.56, depicting a high level of pollution

How warm is too warm for the life cycle of actinopterygian fishes?

We investigated the highest constant temperature at which actinopterygian fishes can complete their lifecycles, based on an oxygen supply model for cleavage-stage eggs. This stage is one of the most heat-sensitive periods during the lifecycle, likely reflecting the exhaustion of maternally supplied heat shock proteins without new production. The model suggests that average eggs would not develop normally under a constant temperature of about 36 °C or higher. This estimate matches published empirical values derived from laboratory and field observations. Spermatogenesis is more heat sensitive than embryogenesis in fishes, so the threshold may indeed be lower, at about 35 °C, unless actinopterygian fishes evolve heat tolerance during spermatogenesis as in birds. Our model also predicts an inverse relationship between egg size and temperature, and empirical data support this prediction. Therefore, the average egg size, and hence hatching size, is expected to shrink in a greenhouse world but a feeding function prohibits the survival of very small hatchlings, posing a limit to the shrinkage. It was once suggested that a marine animal community may be sustained under temperatures up to about 38 °C, and this value is being used, for example, in paleotemperature reconstruction. A revision of the value is overdue. (199/200

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background: Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods: The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results: A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion: Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)