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^(99m)Tc in the evaluation of microleakage of composite resin restorations with SonicFill^(TM).An in vitro experimental model 被引量:1
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作者 Carrilho Eunice Abrantes Margarida +8 位作者 Casalta-Lopes Joao Botelho Filomena Paula Anabela Ambrósio Pedro Marto Carlos Miguel Rebelo Diana Marques Joana Polido Mário Ferreira Manuel Marques 《Open Journal of Stomatology》 2012年第4期340-347,共8页
Introduction: The composite SonicFillTM (Kerr/Kavo) is indicated for posterior restorations, with a single increment up to 5 mm due to reduced polymerization shrinkage, thus reducing working time. Aim: Evaluation of m... Introduction: The composite SonicFillTM (Kerr/Kavo) is indicated for posterior restorations, with a single increment up to 5 mm due to reduced polymerization shrinkage, thus reducing working time. Aim: Evaluation of marginal microleakage with SonicFillTM. Method and Materials: There were sectioned sixty noncarious human molars in the occluso-cervical direction. Class V cavities were prepared on each tooth with gingival margin walls in a standardized way. The specimens were divided into 4 groups: group 1—restored with SonicFillTM (Kerr/Kavo), group 2—restored with FiltekTM SupremeXTE (3M ESPE), group 3—the cavities were not restored;group 4—restored with SonicFillTM (Kerr/Kavo). In groups 1, 2 and 4 the enamel was conditioned with 37% orthophosphoric acid and applied the self-etch adhesive system Clear- fillTM SE BOND (Kuraray). The specimens were stored in distilled water at 37?C for 7 days. After, the specimens, were immersed in a solution of 99mTc-Pertechnetate and the radioactivity was assessed with a gamma camera. The nonparametric Kruskal-Wallis and Mann-Whitney test with Bonferroni correction at a significance level of 5% were used for the statistical analyses. Results: There are significant differences between the positive and negative control groups and between these and experimental groups (p TM and FiltekTM SupremeXTE. Conclusion: The new composite SonicFillTM and FiltekTM SupremeXTE showed no difference concerning dye penetration. The Sonic- FillTM restorative system showed no influence in concerning microleakage. 展开更多
关键词 Posterior resin Composites Composite restorations Polymerization Stress Polymerization Shrinkage MICROLEAKAGE THERMOCYCLING
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Assessment of the Quality of Composite Resin Restorations
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作者 Z. A. Ijaimi N. H. Abu-Bakr Y. E. Ibrahim 《Open Journal of Stomatology》 2015年第2期19-25,共7页
Purpose: To evaluate the quality of the composite restorations. Material and Methods: A total of 246 composite restorations in 125 patients attending the Conservative Dentistry Clinics at the Faculty of Dentistry, Uni... Purpose: To evaluate the quality of the composite restorations. Material and Methods: A total of 246 composite restorations in 125 patients attending the Conservative Dentistry Clinics at the Faculty of Dentistry, University of Khartoum were examined. Both anterior and posterior composite restorations were included. California Dental Association Quality Evaluation System was used for the evaluation. Results: Fifty two percent of all restorations were found to be satisfactory, while the remaining 48% were not satisfactory. With regard to surface and colour criteria, colour mismatch within the range (34.8%) and slight surface roughness (26.6%) were the most common defects. The most frequent defects of the anatomical form were restoration overhang (26.8%). The majority of the restorations above 4 years old were of unacceptable anatomical form (66.7%), and their marginal integrity was less acceptable than more recent restorations (46.7%). Conclusions: Forty eight percent of the examined composite restorations needed to be replaced, and the unacceptable anatomic form was the main cause of failure of composite restorations. 展开更多
关键词 Composite RESIN restorations MARGINAL Defect OVERHANG Restoration COLOUR MISMATCH
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Insightful Understanding of the Role of the Mechanical Properties in Defining the Reliability of All-Ceramic Dental Restorations: A Review
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作者 Mohammad Albakry 《Journal of Biomaterials and Nanobiotechnology》 2021年第4期57-78,共22页
Since the last two decades, restorative dentistry has been witnessing an increased acceptance of the use of the well-known all-ceramic materials for the fabrication of single dental restorations, such as inlays, onlay... Since the last two decades, restorative dentistry has been witnessing an increased acceptance of the use of the well-known all-ceramic materials for the fabrication of single dental restorations, such as inlays, onlays, crowns, anterior and posterior fixed partial dentures (PFPDs). These restorations certainly offer the potential for better biocompatibility coupled with superior aesthetic qualities, especially when compared with the conventional prostheses made from porcelain that is fused with metal ceramic restorations. However, brittleness and extreme sensitivity of all-ceramic materials to micro-like defects or cracks that are inherently present, or may grow, in their microstructure during different laboratory fabrication steps, during necessary clinical adjustments, or from post-placement chewing activity, remain major shortcomings of these dental restorations. In fact, many researchers are of the opinion that the improved mechanical properties can significantly improve the lifetime of all-ceramic restorations and result in enhanced reliability. Therefore, efforts of researchers, as well as manufacturers, have been directed towards the improvement of the mechanical properties in order to overcome such limitations. This article reviews the characterization of the most important mechanical properties that can delineate the behavior of all-ceramic dental materials upon loading. These include fracture mechanics, the brittle nature of ceramics, the relationship between microstructural features and fracture behavior, sources of cracks and flaws that may initiate a fracture and the effect of different fabrication procedures and/or clinical adjustments on the mechanical behavior of dental ceramics are also reviewed and discussed. 展开更多
关键词 Mechanical Properties Fracture Mechanics All-Ceramic Dental restorations Microstructural Features MICROCRACKS
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Bonding Orthodontic Ceramic Brackets to Ceramic Restorations:Evaluation of Different Surface Conditioning Methods
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作者 Andreas Faltermeier Claudia Reicheneder +1 位作者 Peter Gotzfried Peter Proff 《Materials Sciences and Applications》 2013年第7期10-14,共5页
The purpose of this study was to compare the shear bond strength and Adhesive Remnant Index of four different veneering ceramic materials to ceramic brackets. Additionallly, a further aim of this study was to overcome... The purpose of this study was to compare the shear bond strength and Adhesive Remnant Index of four different veneering ceramic materials to ceramic brackets. Additionallly, a further aim of this study was to overcome the etching using hydrofluoric acid which is noxious and could seriously damage the corneas of the eyes. Two surface conditioning methods of four ceramic materials before bonding brackets were examined: in group 1 an air particle abrasion with 25 μm aluminium trioxide (4 seconds at a pressure of 2.5 bars) and subsequently a silane coupling agent (Espe Sil, 3M Unitek, Monrovia, USA) was applicated on one side of each ceramic specimen (10 per group). In group 2 one side of each sample (20 per group) was etched with 37.0 per cent orthophosphoric acid for two minutes and was followed by a silane application (Espe Sil, 3M Unitek, Monrovia, USA). After this procedure the self-ligating ceramic brackets Clarity SL (3M Unitek, Monrovia, USA) brackets were bonded to the ceramic blocks and a thermocycling process started (5°C - 55°C, 6000 cycles). Then, shear bond strength and Adhesive Remnant Index (ARI) were measured. To determine statistical differences Oneway-ANOVA and Tukey Post-hoc test were performed. Hydrofluoric acid seems not to be justifiable anymore for preparing the surface of dental ceramic restorations before bracket bonding. Sandblasting with 25 μm aluminium trioxide and the use of orthophosphoric acid (37.0 per cent) seem to prepare the surface of ceramic restoration sufficiently before ceramic bracket bonding. The found level of shear bond strength values seems to be sufficient for bonding ceramic brackets to ceramic restorations. 展开更多
关键词 Ceramic restorations Ceramic Brackets Aluminium Trioxide Orthophosphoric Acid
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Effect of Nanoparticles Reinforced Adhesive Layers on Microleakage of Tooth Restorations
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作者 Mohamed I. Ebrahim Mohamed Ashour Ahmed Nayef H. Felemban 《World Journal of Nano Science and Engineering》 2016年第2期64-69,共6页
Adhesive layer is an essential part of tooth colored restorations which play an important role in decreasing the microleakage between the tooth and restoration material after polymerization shrinkage. The purpose of t... Adhesive layer is an essential part of tooth colored restorations which play an important role in decreasing the microleakage between the tooth and restoration material after polymerization shrinkage. The purpose of this study was to evaluate the effect of deferent adhesive system of bonding agent on microleakage of nanocomposite resin in class II cavities. Two different types of adhesive systems: universal adhesive (ExciTE) and a newly developed adhesive (Nano-Bond) and one type of light-cured resin restorative material (nanocomposite resin) were used in this study. These adhesives were applied to prepared tooth cavities by either manufactures’ instructions or by an experimental method (single or double application). Nanocomposite resin was then placed and light-cured for 40 seconds. Teeth were subjected to 500 thermal cycles between 5&degC and 55&degC and were immersed in 3% methylene blue solution for 24 hours;microleakage was observed microscopically. The data were analyzed by a two-way ANOVA. For comparison between groups, Tukey’s post-hoc test was used. Nanoparticles reinforced adhesive system shows low microleakage in compare with universal adhesive system, and application of two adhesive layers also can decrease the microleakage. The ability of stress absorption by adhesive layer after polymerization shrinkage of restoration material will reduce the microleakage. 展开更多
关键词 Adhesive Layer Tooth Colored restorations NANOPARTICLES MICROLEAKAGE
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Papillae alterations around single-implant restorations in the anterior maxillae:thick versus thin mucosa 被引量:8
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作者 Mi-Si Si Long—Fei Zhuang +3 位作者 Xin Huang Ying-Xin GU Chung-Hao Chou Hong-Chang Lai 《International Journal of Oral Science》 SCIE CAS CSCD 2012年第2期94-100,共7页
To evaluate the papilla alterations around single-implant restorations in the anterior maxillae after crown attachment and to study the influence of soft tissue thickness on the papilla fill alteration. According to t... To evaluate the papilla alterations around single-implant restorations in the anterior maxillae after crown attachment and to study the influence of soft tissue thickness on the papilla fill alteration. According to the inclusion criteria, 32 patients subjected to implant-supported single-tooth restorations in anterior maxillae were included. The patients were assigned to two groups according to the mucosal thickness: (i) group 1, 1.5 mm≤mucosal thickness≤3 mm; and (ii) group 2, 3 mm〈mucosal thickness≤4.5 mm. Assessments of interproximal papillae at the time of crown placement (baseline) and at 6-month postloading (follow-up) were made by two prosthodontists using papilla fill index (PFI). The mean mucosal thickness was (2.49±0.31) mm (group 1) and (3.81±0.31) mm (group 2) for the two groups respectively. A significant difference in PFI between the groups was detected at the baseline (P〈O.O01). PFI improvements over time occurred after 6-month follow-up irrespective of the groups. When compared to group 1, the likelihood to obtain papilla fill was significantly higher for group 2 with an odds ratio of 6.05 (P〈O.O01). The interproximal papilla level around single-implant restorations could improve significantly over time after 6-month restoration according to PFI assessment. The thicker mucosa before implant placement implied a more favorable esthetic outcome in papilla alteration. 展开更多
关键词 esthetic outcome papilla fill index single-implant restoration soft tissue thickness
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Preconditioned Iterative Methods for Algebraic Systems from Multiplicative Half-Quadratic Regularization Image Restorations 被引量:1
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作者 Michael K.Ng 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2010年第4期461-474,共14页
Image restoration is often solved by minimizing an energy function consisting of a data-fidelity term and a regularization term. A regularized convex term can usually preserve the image edges well in the restored imag... Image restoration is often solved by minimizing an energy function consisting of a data-fidelity term and a regularization term. A regularized convex term can usually preserve the image edges well in the restored image. In this paper, we consider a class of convex and edge-preserving regularization functions, I.e., multiplicative half-quadratic regularizations, and we use the Newton method to solve the correspondingly reduced systems of nonlinear equations. At each Newton iterate, the preconditioned conjugate gradient method, incorporated with a constraint preconditioner, is employed to solve the structured Newton equation that has a symmetric positive definite coefficient matrix.The igenvalue bounds of the preconditioned matrix are deliberately derived, which can be used to estimate the convergence speed of the preconditioned conjugate gradient method. We use experimental results to demonstrate that this new approach is efficient,and the effect of image restoration is r0easonably well. 展开更多
关键词 IMAGE CONJUGATE gradient METHOD IMAGE restoration symmetric positive definite energy function NEWTON METHOD matrix approach results use paper class new
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Twelve-month evaluation of the atraumatic restorative treatment approach for class Ⅲ restorations:An interventional study
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作者 Madhuniranjanswamy Mahalakshmamma Shivanna Shabana Ganesh +4 位作者 Sanjeev Balappa Khanagar Sachin Naik Darshan Devang Divakar Abdulaziz Abdullah Al-Kheraif Chitra Jhugroo 《World Journal of Clinical Cases》 SCIE 2020年第18期3999-4009,共11页
BACKGROUND Atraumatic restorative treatment(ART)may be appropriate for populations without accessibility and affordability.More data are required regarding the success rate of ART in anterior teeth.AIM To evaluate the... BACKGROUND Atraumatic restorative treatment(ART)may be appropriate for populations without accessibility and affordability.More data are required regarding the success rate of ART in anterior teeth.AIM To evaluate the clinical performance of restoring class III cavities in anterior teeth of permanent dentition using the ART approach.METHODS A longitudinal interventional field study was carried out at two rural primary health centers,Tumkur district,India.A total of 54 teeth in 39 patients were evaluated for the survival rate of class III restorations in permanent anterior teeth using the ART approach in children and adult populations.Evaluation of ART restoration was carried out using Frencken J criteria,the mean procedure time,patient acceptance and reported pain severity during the ART approach were evaluated using a visual analog scale.Calculation of the cost of ART was also performed.RESULTS The mean time taken to perform the ART procedure was 14.79±5.8 min with the majority of patients reporting only mild pain.At 6 mo follow-up,72.2%remained in a good state,but this reduced to 27%at 12 mo.The cumulative survival rate of the restorations was 94.4%at 6 mo and 80.9%at 12 mo follow-up.Estimation of the direct cost for a single class III restoration was 186.50 INR(2.64 USD).CONCLUSION ART may be a good comprehensive option for basic oral health care for underserved or inaccessible populations,and preventive care for patients. 展开更多
关键词 Atraumatic restorative treatment Anterior teeth COMPOSITE Glass ionomer cement Permanent dentition Rural area
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Porcelain fracture of metal-ceramic tooth-supported and implant-supported restorations: A review
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作者 Rola M. Shadid Nasrin R. Sadaqah +1 位作者 Layla Abu-Naba’a Wael M. Al-Omari 《Open Journal of Stomatology》 2013年第8期411-418,共8页
Metal-ceramic restorations are widely used in dentistry with a high degree of general success. However, fracture of these restorations does occur and usually frustrates both the dentist and the patient. Objective: Thi... Metal-ceramic restorations are widely used in dentistry with a high degree of general success. However, fracture of these restorations does occur and usually frustrates both the dentist and the patient. Objective: This literature review discusses the factors that may lead to the fracture of these restorations whether they are tooth-supported or implant-supported with the aim of making dentists and technicians aware of these factors to avoid them. Factors reviewed include: technical factors, dentist-related factors, inherent material properties, direction, magnitude and frequency of applied loads, environmental factors, screw-retained implant-supported restorations, and posterior cantilevered prostheses. Material and Methods: A netbased search in “Pubmed” was performed and combined with a manual search. The search was limited to articles written in English. Conclusions: the published literature revealed that the factors predisposing to fracture of metal-ceramic restorations may be related to the technician, dentist, patient, environment, design of the restoration, or to inherent structure of ceramics and others. However, if the dentist and technician understand these factors and respect the physical characteristics of the materials, most of those are avoidable. 展开更多
关键词 Metal-Ceramic Fracture IMPLANT-SUPPORTED Restoration Screw-Retained
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Periodontal Health among Type 2 Diabetes Patients Treated with Different Dental Restorations
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作者 Mohammad Albakry Michael Vincent Swain +2 位作者 Abdo Abdul-Razzaq Falah Alshammary Waleed Asiri 《Open Journal of Stomatology》 2021年第8期278-296,共19页
<strong>Background:</strong> Diabetes increases periodontal disease risk and its complications, which are worsened with age or faulty restorations. <strong>Aim:</strong> Evaluate periodontal he... <strong>Background:</strong> Diabetes increases periodontal disease risk and its complications, which are worsened with age or faulty restorations. <strong>Aim:</strong> Evaluate periodontal health among patients with diabetes treated with different dental restorations. <strong>Materials and Methods:</strong> This comparative cross-sectional study was conducted at the faculty of dentistry, Najran University, KSA, from March 2018 to February 2020. It included 260 diabetics, treated with different dental restorations, divided into four groups, each comprising 65 patients aged 45 - 60 years: Group 1 (G1), no restorations (control group);Group 2 (G2), Class II amalgam restorations;Group 3 (G3), Class II composite resin restorations;and Group 4 (G4), three-unit posterior metal ceramic prostheses. The Ages of all restorations ranged from 8 to 10 years. All groups were assessed for the Plaque Index (PI) and Gingival Index (GI), Overhangs Rate (OR), Alveolar Bone Loss (ABL) (the latter two using panoramic X-ray). HbA1c and duration of participants were also assessed and compared. <strong>Results:</strong> The mean HbA1c results of the groups ranged from 8.1% to 9.5%, and their mean diabetes durations ranged from 7.2 to 12 years. All the groups showed worse periodontal scores, ranging from 2.45 - 2.95 for PI and 2.25 - 2.8 for GI. G2 had higher scores than G1 and G3 (<em>p</em> < 0.001). G4 had the highest two recorded scores (<em>p</em> < 0.001). G2 had a higher rate of overhangs than G3 (<em>p</em> < 0.037). The mean ABL was 44% (SD 6.4) for G1, 56.0% (SD 6.7) for G2, 46.5% (SD 5.8) for G3, and 74.5% (SD 6.4) for G4. The lowest values were recorded in G1 and G3 (<em>p</em> = 0.987). The highest value was observed in G4, which was significantly higher than other groups (<em>p</em> < 0.001). <strong>Conclusion: </strong>The worse periodontal parameters among subjects treated with either three-unit metal ceramic or Class II amalgam restorations indicated severe periodontal destruction. Untreated subjects and subjects treated with Class II composite resin had relatively better periodontal status. 展开更多
关键词 Diabetes Mellitus Alveolar Bone Loss Plaque Index Dental Restoration
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Advantages of nanocarriers for basic research in the field of traumatic brain injury 被引量:1
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作者 Xingshuang Song Yizhi Zhang +1 位作者 Ziyan Tang Lina Du 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期237-245,共9页
A major challenge for the efficient treatment of traumatic brain injury is the need for therapeutic molecules to cross the blood-brain barrier to enter and accumulate in brain tissue.To overcome this problem,researche... A major challenge for the efficient treatment of traumatic brain injury is the need for therapeutic molecules to cross the blood-brain barrier to enter and accumulate in brain tissue.To overcome this problem,researchers have begun to focus on nanocarriers and other brain-targeting drug delivery systems.In this review,we summarize the epidemiology,basic pathophysiology,current clinical treatment,the establishment of models,and the evaluation indicators that are commonly used for traumatic brain injury.We also report the current status of traumatic brain injury when treated with nanocarriers such as liposomes and vesicles.Nanocarriers can overcome a variety of key biological barriers,improve drug bioavailability,increase intracellular penetration and retention time,achieve drug enrichment,control drug release,and achieve brain-targeting drug delivery.However,the application of nanocarriers remains in the basic research stage and has yet to be fully translated to the clinic. 展开更多
关键词 blood-brain barriers brain targeting central nervous system extracellular vesicles inflammatory factor microglial cell NANOCARRIERS nanoparticles neural restoration traumatic brain injury
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Using restored two-dimensional X-ray images to reconstruct the three-dimensional magnetopause 被引量:1
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作者 RongCong Wang JiaQi Wang +3 位作者 DaLin Li TianRan Sun XiaoDong Peng YiHong Guo 《Earth and Planetary Physics》 EI CSCD 2024年第1期133-154,共22页
Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space physics.The Soft X-ray Imager(SXI)carried by the Solar wind Magnetosph... Astronomical imaging technologies are basic tools for the exploration of the universe,providing basic data for the research of astronomy and space physics.The Soft X-ray Imager(SXI)carried by the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)aims to capture two-dimensional(2-D)images of the Earth’s magnetosheath by using soft X-ray imaging.However,the observed 2-D images are affected by many noise factors,destroying the contained information,which is not conducive to the subsequent reconstruction of the three-dimensional(3-D)structure of the magnetopause.The analysis of SXI-simulated observation images shows that such damage cannot be evaluated with traditional restoration models.This makes it difficult to establish the mapping relationship between SXIsimulated observation images and target images by using mathematical models.We propose an image restoration algorithm for SXIsimulated observation images that can recover large-scale structure information on the magnetosphere.The idea is to train a patch estimator by selecting noise–clean patch pairs with the same distribution through the Classification–Expectation Maximization algorithm to achieve the restoration estimation of the SXI-simulated observation image,whose mapping relationship with the target image is established by the patch estimator.The Classification–Expectation Maximization algorithm is used to select multiple patch clusters with the same distribution and then train different patch estimators so as to improve the accuracy of the estimator.Experimental results showed that our image restoration algorithm is superior to other classical image restoration algorithms in the SXI-simulated observation image restoration task,according to the peak signal-to-noise ratio and structural similarity.The restoration results of SXI-simulated observation images are used in the tangent fitting approach and the computed tomography approach toward magnetospheric reconstruction techniques,significantly improving the reconstruction results.Hence,the proposed technology may be feasible for processing SXI-simulated observation images. 展开更多
关键词 Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) soft X-ray imager MAGNETOPAUSE image restoration
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Achievements and challenges of primate conservation in China 被引量:1
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作者 Bao-Guo Li He Zhang +21 位作者 Ming Li Xue-Long Jiang Peng-Fei Fan Jiang Zhou Song-Tao Guo Xiao-Guang Qi Jin-Hua Li Ji-Qi Lu Dong-Po Xia Liang-Wei Cui Zuo-Fu Xiang Qi-Hai Zhou Zhi-Pang Huang Cheng-Ming Huang Wen Xiao Hui-Jian Hu Zhi-Xin Zhou Ming-Yong Chen Da-Yong Li Peng-Lai Fan Yin Yang Ru-Liang Pan 《Zoological Research(Diversity and Conservation)》 2024年第1期66-74,共9页
The dual impact of climate change and human activities has precipitated a sharp decline in primate biodiversity globally.China is home to the most diverse primate species in the Northern hemisphere,which face severe e... The dual impact of climate change and human activities has precipitated a sharp decline in primate biodiversity globally.China is home to the most diverse primate species in the Northern hemisphere,which face severe ecological threats due to the expansion of modern agriculture,extensive exploitation and consumption of natural resources,and excessive land development during its transition from an agricultural to a modern society.In response,China has implemented various ecological conservation measures,including habitat restoration and protection.These efforts have made substantial strides in biodiversity conservation,with certain regions witnessing an increase in primate populations.In the current study,we conducted a systematic review of historical documents and field research data related to Chinese primates,evaluating the endangered status of primate species in China.Despite improvements in the habitats of most primate species and some population growth,many species still face severe threats,including declining and small populations.Species such as the Myanmar snub-nosed monkey(Rhinopithecus strykeri),eastern black crested gibbon(Nomascus nasutus),and Hainan gibbon(N.hainanus)remain particularly vulnerable due to their limited distribution ranges and extremely small populations.Insufficient scientific data,fragmented information,and not enough studies in conservation biology further compound the challenges.Moreover,there is a notable lack of detailed population monitoring data for species such as the Bengal slow loris(Nycticebus bengalensis),pygmy slow loris(N.pygmaeus),Indochinese gray langur(Trachypithecus crepusculus),Shortridge’s langur(T.shortridgei),and capped langur(T.pileatus),which hinders the development of practical and targeted conservation management strategies.Therefore,for national biodiversity conservation,there is an urgent need for specialized primate surveys,enhancing habitat protection and restoration,and increasing focus on cross-border conservation strategies and regional cooperation.There is also a need to establish a comprehensive and systematic research database platform,conduct continuous and in-depth research in primate biology,and actively engage in the scientific assessment of ecotourism.Additionally,strengthening public awareness and education on wildlife conservation remains essential.Such integrated and systematic efforts will provide scientific support for the current and future conservation and management of primate species in China. 展开更多
关键词 PRIMATES BIODIVERSITY Habitat fragmentation Habitat restoration Conservation strategies
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Stepwise Ecological Restoration:A framework for improving restoration outcomes
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作者 Junguo Liu Yuehan Dou He Chen 《Geography and Sustainability》 CSCD 2024年第2期160-166,共7页
Ecosystem degradation is one of the critical constraints for the sustainable development of our planet.However,recovering an ecosystem to a pre-impairment condition is often not practical.The International Restoration... Ecosystem degradation is one of the critical constraints for the sustainable development of our planet.However,recovering an ecosystem to a pre-impairment condition is often not practical.The International Restoration Standards provide the first framework for practical guidance on what constitutes the process of ecological repair and how this repair process can be influenced to improve net ecological benefits.In these Standards,Restorative Continuum is highlighted and it recognises that many do not,yet there is still value in aspiring to improvements to the highest extent possible,with some sites potentially being able to be improved in a stepwise manner.Here we elaborate on these Standards by providing a cross-ecosystem theoretical framework of Stepwise Ecological Restoration(STERE)for promoting higher environmental benefits.STERE allows the selection of suitable restorative modes by considering the degree of degradation while encouraging a transition to a higher state.These models include environmental remediation for completely modified and degraded ecosystems,ecological rehabilitation for highly modified and degraded ecosystems,and ecological restoration for degraded native ecosystems.STERE requires selecting tailored restorative modes,setting clear restorative targets and reference ecosystems,applying a systematic-thinking approach,and implementing a continuous monitoring program at all process stages to achieve a resilient trajectory.STERE allows adaptive management in the context of climate change,and when the evidence is available,to“adapt to the future”to ensure climate resilience.The STERE framework could assist in initiating and implementing restoration projects worldwide,especially in developing countries. 展开更多
关键词 Ecological restoration Reference ecosystem Restorative modes Sustainable development
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Restoration of the JPEG Maximum Lossy Compressed Face Images with Hourglass Block-GAN
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作者 Jongwook Si Sungyoung Kim 《Computers, Materials & Continua》 SCIE EI 2024年第3期2893-2908,共16页
In the context of high compression rates applied to Joint Photographic Experts Group(JPEG)images through lossy compression techniques,image-blocking artifacts may manifest.This necessitates the restoration of the imag... In the context of high compression rates applied to Joint Photographic Experts Group(JPEG)images through lossy compression techniques,image-blocking artifacts may manifest.This necessitates the restoration of the image to its original quality.The challenge lies in regenerating significantly compressed images into a state in which these become identifiable.Therefore,this study focuses on the restoration of JPEG images subjected to substantial degradation caused by maximum lossy compression using Generative Adversarial Networks(GAN).The generator in this network is based on theU-Net architecture.It features a newhourglass structure that preserves the characteristics of the deep layers.In addition,the network incorporates two loss functions to generate natural and high-quality images:Low Frequency(LF)loss and High Frequency(HF)loss.HF loss uses a pretrained VGG-16 network and is configured using a specific layer that best represents features.This can enhance the performance in the high-frequency region.In contrast,LF loss is used to handle the low-frequency region.The two loss functions facilitate the generation of images by the generator,which can mislead the discriminator while accurately generating high-and low-frequency regions.Consequently,by removing the blocking effects frommaximum lossy compressed images,images inwhich identities could be recognized are generated.This study represents a significant improvement over previous research in terms of the image resolution performance. 展开更多
关键词 JPEG lossy compression RESTORATION image generation GAN
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Lactate is a potentially harmful substitute for brain glucose fuel:consequences for metabolic restoration of neurotransmission
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作者 Oliver Kann Lennart Soder Babak Khodaie 《Neural Regeneration Research》 SCIE CAS 2025年第5期1403-1404,共2页
The metabolite lactate (L-lactate) can be generated and released by diverse brain cells,including neurons,astrocytes,and oligodendrocytes (Kann,2023;Rae et al.,2024).Lactate production usually requires the degradation... The metabolite lactate (L-lactate) can be generated and released by diverse brain cells,including neurons,astrocytes,and oligodendrocytes (Kann,2023;Rae et al.,2024).Lactate production usually requires the degradation of glucose (D-glucose)-and glycogen in astrocytes-to pyruvate by glycolysis and subsequent conversion of pyruvate to lactate by the enzyme lactate dehydrogenase(Figure 1A;Dienel,2019;Rae et al.,2024). 展开更多
关键词 consequences FIGURE RESTORATION
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深海环境海洋生态系统监测与修复新技术
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作者 Jacopo Aguzzi Laurenz Thomsen +16 位作者 Sascha Flögel Nathan J.Robinson Giacomo Picardi Damianos Chatzievangelou Nixon Bahamon Sergio Stefanni Jordi Grinyó Emanuela Fanelli Cinzia Corinaldesi Joaquin Del Rio Fernandez Marcello Calisti Furu Mienis Elias Chatzidouros Corrado Costa Simona Violino Michael Tangherlini Roberto Danovaro 《Engineering》 SCIE EI CAS CSCD 2024年第3期195-211,共17页
The United Nations(UN)’s call for a decade of“ecosystem restoration”was prompted by the need to address the extensive impact of anthropogenic activities on natural ecosystems.Marine ecosystem restoration is increas... The United Nations(UN)’s call for a decade of“ecosystem restoration”was prompted by the need to address the extensive impact of anthropogenic activities on natural ecosystems.Marine ecosystem restoration is increasingly necessary due to increasing habitat degredation in deep waters(>200 m depth).At these depths,which are far beyond those accessible by divers,only established and emerging robotic platforms such as remotely operated vehicles(ROVs),autonomous underwater vehicles(AUVs),landers,and crawlers can operate through manipulators and multiparametric sensor arrays(e.g.,optoacoustic imaging,omics,and environmental probes).The use of advanced technologies for deep-sea ecosystem restoration can provide:①high-resolution three-dimensional(3D)imaging and acoustic mapping of substrates and key taxa,②physical manipulation of substrates and key taxa,③real-time supervision of remote operations and long-term ecological monitoring,and④the potential to work autonomously.Here,we describe how robotic platforms with in situ manipulation capabilities and payloads of innovative sensors could autonomously conduct active restoration and monitoring across large spatial scales.We expect that these devices will be particularly useful in deep-sea habitats,such as①reef-building cold-water corals,②soft-bottom bamboo corals,and③soft-bottom fishery resources that have already been damaged by offshore industries(i.e.,fishing and oil/gas). 展开更多
关键词 Ecosystem restoration Robotic manipulation Acoustic tracking Fishery resources Artificial reefs
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Floristic composition and edaphic relationships in ferruginous campo rupestre reference ecosystems
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作者 G.Wilson FERNANDES Letícia RAMOS +3 位作者 Dario C.PAIVA Jéssica CUNHA-BLUM Vanessa Matos GOMES Daniel NEGREIROS 《Journal of Mountain Science》 SCIE CSCD 2024年第3期719-733,共15页
Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the planet.Some environments with high economic relevance,such as the ferrugin... Land use change and occupation have led to modifications in the environment causing loss of biodiversity and ecosystem services throughout the planet.Some environments with high economic relevance,such as the ferruginous campo rupestre(rupestrian grassland known as Canga in Brazil),are even more susceptible to severe impacts due to their extreme habitat conditions and low resilience.The determination of reference ecosystems based on the intrinsic characteristics of the ecosystem is essential for conservation as well as to the implementation of ecological restoration.We proposed the reference ecosystem of the three main types of habitats of the ferruginous campo rupestre based on their floristic composition.We described the floristic composition of each habitat and evaluated the physicochemical properties of the soils and the relationship between plants and soils.All three habitats showed high diversity of plant species and many endemic species,such as Chamaecrista choriophylla,Cuphea pseudovaccinium,Lychnophora pinaster,and Vellozia subalata.The distribution of vegetation was strongly related with the edaphic characteristics,with a set of species more adapted to high concentration of base saturation,fine sand,organic carbon,and iron,while another set of species succeeded in more acidic soils with higher S and silt concentration.We provide support for the contention that the ferruginous campo rupestre is a mosaic of different habitats shaped by intrinsic local conditions.Failure to recognize the floristic composition of each particular habitat can lead to inappropriate restoration,increased habitat homogenization and increased loss of biodiversity and ecosystem services.This study also advances the knowledge base for building the reference ecosystem for the different types of ferruginous campo rupestre habitats,as well as a key database for highlighting those species contribute most to community assembly in this diverse and threatened tropical mountain ecosystem. 展开更多
关键词 Canga Ecological restoration Extreme ecosystem Non-forest ecosystems Rupestrian grassland Taxon environment relationships
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Spatiotemporal characteristics of seed rain and soil seed bank of artificial Caragana korshinskii Kom. forest in the Tengger Desert, China
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作者 SHEN Jianxiang WANG Xin +9 位作者 WANG Lei WANG Jiahui QU Wenjie ZHANG Xue CHANG Xuanxuan YANG Xinguo CHEN Lin QIN Weichun ZHANG Bo NIU Jinshuai 《Journal of Arid Land》 SCIE CSCD 2024年第4期550-566,共17页
Vegetation restoration and reconstruction are effective approaches to desertification control and achieving social and economic sustainability in desert areas.However,the self-succession ability of native plants durin... Vegetation restoration and reconstruction are effective approaches to desertification control and achieving social and economic sustainability in desert areas.However,the self-succession ability of native plants during the later periods of vegetation restoration remains unclear.Therefore,this study was conducted to bridge the knowledge gap by investigating the regeneration dynamics of artificial forest under natural conditions.The information of seed rain and soil seed bank was collected and quantified from an artificial Caragana korshinskii Kom.forest in the Tengger Desert,China.The germination tests were conducted in a laboratory setting.The analysis of species quantity and diversity in seed rain and soil seed bank was conducted to assess the impact of different durations of sand fixation(60,40,and 20 a)on the progress of vegetation restoration and ecological conditions in artificial C.korshinskii forest.The results showed that the top three dominant plant species in seed rain were Echinops gmelinii Turcz.,Eragrostis minor Host.,and Agropyron mongolicum Keng.,and the top three dominant plant species in soil seed bank were E.minor,Chloris virgata Sw.,and E.gmelinii.As restoration period increased,the density of seed rain and soil seed bank increased first and then decreased.While for species richness,as restoration period increased,it gradually increased in seed rain but decreased in soil seed bank.There was a positive correlation between seed rain density and soil seed bank density among all the three restoration periods.The species similarity between seed rain or soil seed bank and aboveground vegetation decreased with the extension of restoration period.The shape of the seeds,specifically those with external appendages such as spines and crown hair,clearly had an effect on their dispersal,then resulting in lower seed density in soil seed bank.In addition,precipitation was a crucial factor in promoting rapid germination,also resulting in lower seed density in soil seed bank.Our findings provide valuable insights for guiding future interventions during the later periods of artificial C.korshinskii forest,such as sowing and restoration efforts using unmanned aerial vehicles. 展开更多
关键词 ecological restoration soil seed bank seed rain artificial forest vegetation desertification Caragana korshinskii Tengger Desert
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Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) prefer shells for nesting:A field experiment
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作者 Macarena Castro Andrés De la Cruz +1 位作者 Nuria Martin-Sanjuan Alejandro Pérez-Hurtado 《Avian Research》 SCIE CSCD 2024年第1期55-59,共5页
Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal wetlands.However,supratidal habitats as saltpans could play a role in buffering human impact.Saltpans have shown to be... Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal wetlands.However,supratidal habitats as saltpans could play a role in buffering human impact.Saltpans have shown to be important as feeding or breeding sites of some shorebird species.A potential conservation strategy to increase shorebird populations in saltpans is to manipulate the cues that birds use to select optimal breeding habitat.Here it is hypothesized that shorebirds are attracted to bivalve shells due to the advantages they offer.Following this hypothesis,we supplemented a restored saltpan in 2019 and 2021 with bivalve shells,expecting an increase in the number of breeding birds’ nests.More than 75% of Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) nests were found in patches with shells in both years.The best model for both species indicates that the presence of shells is the factor that most correlates with the location of nests.The probability of choosing one place over another to settle their nest increases in areas with an abundance of shells,double in the case of the Kentish Plover and triple in the case of the Little Tern.The result of this study may constitute a valuable tool for attracting birds to restored saltpans and could contribute to the success of expensive restoration projects where time is usually a constraint. 展开更多
关键词 Habitat management Nest site selection Saltpan restoration Shell supplementation SHOREBIRDS
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