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1.
Glob Chang Biol ; 30(1): e17142, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273519

RESUMO

Manual outdoor work is essential in many agricultural systems. Climate change will make such work more stressful in many regions due to heat exposure. The physical work capacity metric (PWC) is a physiologically based approach that estimates an individual's work capacity relative to an environment without any heat stress. We computed PWC under recent past and potential future climate conditions. Daily values were computed from five earth system models for three emission scenarios (SSP1-2.6, SSP3-7.0, and SSP5-8.5) and three time periods: 1991-2010 (recent past), 2041-2060 (mid-century) and 2081-2100 (end-century). Average daily PWC values were aggregated for the entire year, the growing season, and the warmest 90-day period of the year. Under recent past climate conditions, the growing season PWC was below 0.86 (86% of full work capacity) on half the current global cropland. With end-century/SSP5-8.5 thermal conditions this value was reduced to 0.7, with most affected crop-growing regions in Southeast and South Asia, West and Central Africa, and northern South America. Average growing season PWC could falls below 0.4 in some important food production regions such as the Indo-Gangetic plains in Pakistan and India. End-century PWC reductions were substantially greater than mid-century reductions. This paper assesses two potential adaptions-reducing direct solar radiation impacts with shade or working at night and reducing the need for hard physical labor with increased mechanization. Removing the effect of direct solar radiation impacts improved PWC values by 0.05 to 0.10 in the hottest periods and regions. Adding mechanization to increase horsepower (HP) per hectare to levels similar to those in some higher income countries would require a 22% increase in global HP availability with Sub-Saharan Africa needing the most. There may be scope for shifting to less labor-intensive crops or those with labor peaks in cooler periods or shift work to early morning.


Assuntos
Agricultura , Mudança Climática , Temperatura Alta , Produtos Agrícolas , América do Sul
2.
Glob Chang Biol ; 29(9): 2557-2571, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36652298

RESUMO

Temperate perennial fruit and nut trees play varying roles in world food diversity-providing edible oils and micronutrient, energy, and protein dense foods. In addition, perennials reuse significant amounts of biomass each year providing a unique resilience. But they also have a unique sensitivity to seasonal temperatures, requiring a period of dormancy for successful growing season production. This paper takes a global view of five temperate tree fruit crops-apples, cherries, almonds, olives, and grapes-and assesses the effects of future temperature changes on thermal suitability. It uses climate data from five earth system models for two CMIP6 climate scenarios and temperature-related indices of stress to indicate potential future areas where crops cannot be grown and highlight potential new suitable regions. The loss of currently suitable areas and new additions in new locations varies by scenario. In the southern hemisphere (SH), end-century (2081-2100) suitable areas under the SSP 5-8.5 scenario decline by more than 40% compared to a recent historical period (1991-2010). In the northern hemisphere (NH) suitability increases by 20% to almost 60%. With SSP1-2.6, however, the changes are much smaller with SH area declining by about 25% and NH increasing by about 10%. The results suggest substantial restructuring of global production for these crops. Essentially, climate change shifts temperature-suitable locations toward higher latitudes. In the SH, most of the historically suitable areas were already at the southern end of the landmass limiting opportunities for adaptation. If breeding efforts can bring chilling requirements for the major cultivars closer to that currently seen in some cultivars, suitable areas at the end of the century are greater, but higher summer temperatures offset the extent. The high value of fruit crops provides adaptation opportunities such as cultivar selection, canopy cooling using sprinklers, shade netting, and precision irrigation.


Assuntos
Mudança Climática , Frutas , Temperatura , Melhoramento Vegetal , Temperatura Baixa , Produtos Agrícolas
3.
Glob Chang Biol ; 27(22): 5762-5772, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34410027

RESUMO

Anthropogenic climate change is expected to have major impacts on domesticated livestock, including increased heat stress in animals in both intensive and extensive livestock systems. We estimate the changes in the number of extreme heat stress days per year for animals raised outdoors that can be expected in the major domesticated animal species (cattle, sheep, goats, poultry, and pigs) across the globe during this century. We used the temperature humidity index as a proxy for heat stress, calculated using temperature and relative humidity data collated from an ensemble of CMIP6 climate model output for mid and end century. We estimate changes in the proportions of different livestock species that may be at increased risk of extreme heat stress under two contrasting greenhouse gas emission scenarios. Results are discussed in relation to changes in the suitability of different climate conditions for domesticated livestock during the current century. We find that by end century, extreme heat stress risk is projected to increase for all livestock species in many parts of the tropics and some of the temperate zones, and to become climatically more widespread, compared to 2000. Although adaptation options exist for both intensive and extensive livestock production systems, the increasing pervasiveness of extreme heat stress risk in the future will seriously challenge the viability of outdoor livestock keeping, particularly in the lower latitudes in lower and middle-income countries where the costs of adaptation may be challenging to address.


Assuntos
Calor Extremo , Transtornos de Estresse por Calor , Animais , Bovinos , Mudança Climática , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico , Temperatura Alta , Gado , Ovinos , Suínos
4.
Sensors (Basel) ; 21(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799632

RESUMO

High orthodontic forces and various directions of applied forces can be associated with loosening of the screw anchorage in the bone. Screw designs have been modified to increase the stability of the miniscrews. This research evaluates the influence of three-designs on the stability of orthodontic miniscrews. A conventionally cylinder-type miniscrew design (Bio-Action screw, Jin-Biomed co., Bucheon, Korea) was set as a control, and three conditions were studied based on modifications of this control design. Condition-1 has narrowed threads in the upper part of the screw; Condition-2 has a notch at the middle part; and Condition-3 has the combination of Condition-1 and Condition-2. The moment required to unwind the miniscrew to five degrees is tested, and the moment generated at the cortical bone and the trabecular bone were calculated with finite element analysis. Compared to the control, all three conditions showed a higher moment required to unwind the miniscrew and a higher moment generated at the cortical bone. At the trabecular bone, condition-2 and -3 showed higher moment than the control, and condition-1 showed similar moment to the control. Condition-3 required a higher overall moment to unwind the miniscrew. These findings validate the design modifications used to increase the rotational resistance.


Assuntos
Procedimentos de Ancoragem Ortodôntica , Parafusos Ósseos , Análise de Elementos Finitos , República da Coreia , Titânio
5.
Sensors (Basel) ; 21(11)2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34070904

RESUMO

The orthodontic miniscrew is driven into bone in a clockwise direction. Counter-clockwise rotational force applied to the implanted miniscrew can degrade the stability. The purpose of this three-dimensional finite element study was to figure out the effect of shifting the miniscrew head hole position from the long axis. Two miniscrew models were developed, one with the head hole at the long axis and the other with an eccentric hole position. One degree of counter-clockwise rotation was applied to both groups, and the maximum Von-Mises stress and moment was measured under various wire insertion angles from -60° to +60°. All Von-Mises stress and moments increased with an increase in rotational angle or wire insertion angle. The increasing slope of moment in the eccentric hole group was significantly higher than that in the centric hole group. Although the maximum Von-Mises stress was higher in the eccentric hole group, the distribution of stress was not very different from the centric hole group. As the positive wire insertion angles generated a higher moment under a counter-clockwise rotational force, it is recommended to place the head hole considering the implanting direction of the miniscrew. Clinically, multidirectional and higher forces can be applied to the miniscrew with an eccentric head hole position.


Assuntos
Procedimentos de Ancoragem Ortodôntica , Parafusos Ósseos , Análise de Elementos Finitos , Fenômenos Mecânicos , Estresse Mecânico
6.
Sensors (Basel) ; 21(2)2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33445758

RESUMO

This study was designed to develop and verify a fully automated cephalometry landmark identification system, based on multi-stage convolutional neural networks (CNNs) architecture, using a combination dataset. In this research, we trained and tested multi-stage CNNs with 430 lateral and 430 MIP lateral cephalograms synthesized by cone-beam computed tomography (CBCT) to make a combination dataset. Fifteen landmarks were manually and respectively identified by experienced examiner, at the preprocessing phase. The intra-examiner reliability was high (ICC = 0.99) in manual identification. The results of prediction of the system for average mean radial error (MRE) and standard deviation (SD) were 1.03 mm and 1.29 mm, respectively. In conclusion, different types of image data might be the one of factors that affect the prediction accuracy of a fully-automated landmark identification system, based on multi-stage CNNs.


Assuntos
Pontos de Referência Anatômicos , Cefalometria/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Redes Neurais de Computação , Anormalidades Craniofaciais/diagnóstico por imagem , Bases de Dados Factuais , Humanos , Imageamento Tridimensional/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos
7.
Sensors (Basel) ; 21(5)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802443

RESUMO

The aim of this study was to present an optimal diagnostic protocol by comparing and analyzing a conventional examination and the quantitative light-induced fluorescence (QLF) technique. Selected were 297 teeth of 153 patients to take QLF images and bitewing radiographs. Occlusal dental caries, proximal dental caries and cracks were evaluated and scored using QLF, X-ray and/or visual criteria. The sensitivity, specificity, and area under the curve (AUC) of a receiver operating characteristic analysis were calculated. Two fluorescence parameters (|ΔFmax| and ΔRmax) were utilized to evaluate the fluorescence pattern according to the severity of lesions based on QLF or X-ray criteria. QLF showed higher scores for detecting occlusal dental caries and cracks than the conventional method. ΔRmax increased more clearly than ΔFmax did with occlusal dental caries. The |ΔFmax| values of occlusal dental caries, proximal dental caries and cracks showed good AUC levels (0.84, 0.81 and 0.83, respectively). The ΔRmax of occlusal dental caries showed the highest AUC (0.91) and the ΔRmax of proximal dental caries showed a fail level (0.59) compared to bitewing radiographs. The QLF image could visualize and estimate the degree of occlusal dental caries or cracks. Consequently, the QLF technique may be an adjunct tool to conventional methods for the detection of occlusal caries and peripheral cracks.


Assuntos
Cárie Dentária , Fluorescência Quantitativa Induzida por Luz , Dente , Cárie Dentária/diagnóstico por imagem , Fluorescência , Humanos , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade
8.
Sensors (Basel) ; 21(2)2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33451097

RESUMO

The aim of this preliminary study was to evaluate the short-term changes of occlusal contacts and muscle activity after orthodontic treatment during the use of a multi-layer clear retainer. Evaluation was done with the T-scan and BioEMG systems. A total of 18 subjects were included, who were evaluated at three time intervals-T0 at debonding, T1 at one month after retainer delivery, and T2 at four months after retainer delivery. The T-scan and electromyography (EMG) data were recorded simultaneously. The T-scan system recorded the occlusion time, disclusion time and force distribution. The EMG waves were quantified by calculating the asymmetry index and activity index. The time variables changed but not significantly. Occlusal force decreased in the anterior dentition and increased in the posterior dentition during T0-T2. There was no clear evidence of a relationship between unbalanced occlusal forces and muscle activity. In most subjects, the temporalis anterior muscle was more dominant than the masseter muscle. From this preliminary computerized study, there were no significant changes in the state of the occlusion or muscle activity during the short-term retention period.


Assuntos
Músculo Masseter , Adolescente , Adulto , Força de Mordida , Eletromiografia , Feminino , Humanos , Masculino , Músculo Temporal , Dente , Adulto Jovem
9.
Am J Orthod Dentofacial Orthop ; 159(4): 460-469, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33526299

RESUMO

INTRODUCTION: To investigate the anatomy of the posterior palatal alveolar process, which is often used for placement of the orthodontic mini-implant (OMI), and to suggest simple guidelines for safe placement of OMI. METHODS: Cone-beam computed tomography (CBCT) scans of 60 patients (30 men, 30 women; age range, 18-39 years; average age, 25.8 years) was used to measure the palatal interradicular distance, the palatal bone thickness, and the palatal soft-tissue thickness. Measurements were performed on the area from the maxillary canine to the maxillary second molar based on the vertical distance apical from the cementoenamel junction. The CBCT data were analyzed by Bonferroni correction for multiple testing and the multivariable mixed linear model. RESULTS: The palatal interradicular distance was the widest between the second premolar and the first molar and the narrowest between the first and second premolars. The palatal bone thickness at interdental sites was the thickest between the first and second premolars and the thinnest between the first and second molars. The interdental palatal soft-tissue thickness from the canine to the second premolar was thicker than any other area. There were minor measurement differences between genders and positive correlations between vertical distance from the cementoenamel junction plane and all of the parameters. CONCLUSION: In this study, we evaluated the anatomy of the posterior palatal area using CBCT scans of adult patients. The data will provide guidelines to the clinicians before OMI placement in the posterior palatal alveolar process.


Assuntos
Implantes Dentários , Procedimentos de Ancoragem Ortodôntica , Adolescente , Adulto , Processo Alveolar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Maxila , Raiz Dentária , Adulto Jovem
10.
Am J Orthod Dentofacial Orthop ; 158(5): 752-758, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32863085

RESUMO

Nonmineralized cysts and cyst-like lesions that frequently occur in the mandible include ameloblastomas, odontogenic keratocysts, and dentigerous cysts. They have specific features of well-demarcated, unilocular, and radiolucent lesions that are often associated with tooth impaction. Although it rarely occurs, these cysts can become extremely large. Furthermore, cyst enlargement causes additional symptoms that can challenge the success of tooth recovery through orthodontic treatment. This clinical report presents the successful eruption of 2 impacted molars in a large dentigerous cyst treated with marsupialization and orthodontic traction using an orthodontic miniplate anchorage over a 4-year treatment period.


Assuntos
Cisto Dentígero , Cistos Odontogênicos , Dente Impactado , Cisto Dentígero/diagnóstico por imagem , Cisto Dentígero/cirurgia , Humanos , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Erupção Dentária , Dente Impactado/diagnóstico por imagem , Dente Impactado/cirurgia
12.
Orthod Craniofac Res ; 22 Suppl 1: 149-153, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31074131

RESUMO

OBJECTIVES: To conduct a prospective pilot trial to test the clinical efficacy and accuracy of a newly developed Bluetooth-enabled retainer, which was synchronized with an iOS mobile application, cloud database and provider webpage. SETTING AND SAMPLE POPULATION: Five orthodontic residents in a university setting. MATERIAL AND METHODS: At the delivery of the retainers (T0), each participant was given an Bluetooth-enabled retainer, logbook and iPod Touch installed with the mobile application. Participants were instructed to wear the retainer for 12 hours per day and record in the logbook each time the retainer was inserted or removed and trained to synchronize the device daily to the mobile application. After the 5-day study period (T1), statistical analysis was performed comparing the device-reported data to the logbook data using two calculation methods. RESULTS: From T0 - T1, the participants wore their retainers for a median of 11.55 hours per day and the median difference between the self-reported (logbook) data and the device data was 35 minutes or 5.1% over the 5-day study period. Using an adjusted method to calculate the device-reported wear time, the median error was 13 minutes or 1.9%. CONCLUSION: Subjects were able to successfully wear the retainer and upload the data to the mobile application and cloud database. Patient compliance and technical issues could be monitored daily via the provider webpage, and early intervention was possible with reminder messaging. The Bluetooth-enabled retainer showed a clinically acceptable level of accuracy and usability that validates it for future clinical testing.


Assuntos
Contenções Ortodônticas , Cooperação do Paciente , Humanos , Desenho de Aparelho Ortodôntico , Projetos Piloto , Estudos Prospectivos , Resultado do Tratamento
13.
Am J Orthod Dentofacial Orthop ; 156(4): 566-573, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31582128

RESUMO

INTRODUCTION: Accurate root position is imperative for successful orthodontic treatment that is stable and functional. Current methods to monitor root position are either inaccurate or use relatively high levels of radiation. A method to generate an expected root position (ERP) setup has been reported to have the potential to accurately evaluate root position with minimal radiation. The purpose of this study was to determine the accuracy and reliability of the clinical decisions made on root position using the ERP setup. METHODS: This retrospective study included 10 subjects who had pretreatment and midtreatment cone-beam computed tomography (CBCT) scans and study models. An ERP setup was generated for all patients at midtreatment. Four examiners assessed both the CBCT scan and ERP setup and made clinical decisions regarding the root position with each method. Cohen's kappa was determined to assess intraoperator and intermethod reliability. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated to determine the accuracy of the ERP setup. RESULTS: The kappa values for intraoperator reliability for both the CBCT scan and ERP setup fell within the 0.61-0.80 range. The kappa values for intermethod reliability between the CBCT scan and ERP setup fell within the 0.61-0.80 range for all tooth groups. The sensitivity of the ERP setup ranged from 0.72 to 0.90, specificity ranged from 0.89 to 0.97, positive predictive value ranged from 0.57 to 0.85, and negative predictive value ranged from 0.93 to 0.99. CONCLUSIONS: This study demonstrated that the ERP setup, when compared with the gold standard CBCT scan, was accurate and reliable in making clinical decisions regarding root position at midtreatment.


Assuntos
Tomada de Decisão Clínica , Tomografia Computadorizada de Feixe Cônico/métodos , Imageamento Tridimensional/métodos , Técnicas de Movimentação Dentária , Raiz Dentária/anatomia & histologia , Raiz Dentária/diagnóstico por imagem , Humanos , Modelos Dentários , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
14.
Am J Orthod Dentofacial Orthop ; 155(2): 276-287, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30712699

RESUMO

Congenital absence of permanent teeth can be treated by means of dental implants and prosthetics. Tooth autotransplantation is an alternative in growing patients because continued eruption of the transplanted tooth and associated alveolar bone growth can be expected. This clinical report presents tooth autotransplantation in a 10-year-old boy with chronic maxillary rhinosinusitis, diagnosed by the department of otorhinolaryngology. The patient's mandibular second premolars were transplanted to a congenitally edentulous maxillary premolar region. There was insufficient alveolar bone during transplantation because of pneumatization, but normal root development with vertical alveolar bone growth was observed during a 3-year follow-up. Healing of the transplant in the right side without closing of the apex and without signs of obliteration after 4 years is exceptional.


Assuntos
Dente Pré-Molar/anormalidades , Dente Pré-Molar/transplante , Fechamento de Espaço Ortodôntico , Criança , Doença Crônica , Humanos , Masculino , Mandíbula , Sinusite Maxilar/complicações , Rinite/complicações , Transplante Autólogo
15.
J Craniofac Surg ; 29(1): e64-e68, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29065047

RESUMO

BACKGROUND: This article presents an alternate surgical treatment method to correct a severe anterior protrusion in the adult patient with an extremely thin alveolus. METHODS: In the maxilla, a wide linear corticotomy was performed under local anesthesia. Cortical alveolar bone of the upper first bicuspids area was widely removed. Orthopedic force for bony block movement was applied by a palatal bone-borne type retractor supported by skeletal anchorage. Residual extraction space closure was performed by biocreative orthodontics strategy (BOS). In the mandible, an anterior segmental osteotomy (ASO) and extraction of 1st premolars were performed under local anesthesia. RESULTS: In the maxilla, bony block movement followed by the wide linear corticotomy with a palatal bone-borne type retractor was implemented without complications. Remaining extraction space after the bony block movement was closed effectively by BOS. In the mandible, anterior segmental retraction was achieved effectively by ASO. CONCLUSIONS: Wide linear corticotomy with a palatal bone-borne type retractor and ASO under local anesthesia can be an effective alternative to orthognathic surgery in adults with protrusion and an extremely thin alveolus. The biocreative strategy also provides a simple and effective method to retract the 6 anterior teeth.


Assuntos
Má Oclusão/cirurgia , Mandíbula/cirurgia , Maxila/cirurgia , Procedimentos Cirúrgicos Bucais , Palato/cirurgia , Adulto , Humanos
16.
Am J Orthod Dentofacial Orthop ; 154(4): 583-595, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30268268

RESUMO

INTRODUCTION: Current methods to evaluate root position either are inaccurate (panoramic radiograph) or expose patients to relatively large amounts of radiation (cone-beam computed tomography [CBCT]). A method to evaluate root position by generating an expected root position (ERP) setup was recently reported but has not been validated. The purpose of this study was to quantitatively assess the accuracy and reliability of the ERP setup with adequate statistical power. METHODS: This retrospective study included 15 subjects who had completed phase 2 orthodontic treatment. An ERP setup was generated for all patients after treatment. The ERP setup was compared with the posttreatment CBCT scan, which served as the control. The mesiodistal angulation and buccolingual inclination of all teeth in both the ERP setup and the posttreatment CBCT scan were measured and compared. Bland-Altman analysis was used to assess interoperator reliability, intraoperator reliability, and agreement between the ERP setup and the posttreatment CBCT scan. RESULTS: Bland-Altman plots showed high interoperator and intraoperator reliabilities. These plots also showed strong agreement between the ERP setup and the posttreatment CBCT scan; 11.8% of teeth measured for mesiodistal angulation and 9.6% of teeth measured for buccolingual inclination were outside the ±2.5° range of clinical acceptability. CONCLUSIONS: We validated that the method to generate an ERP setup to evaluate root position for posttreatment orthodontic assessment is accurate and reliable.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Imageamento Tridimensional/métodos , Ortodontia Corretiva , Raiz Dentária/anatomia & histologia , Raiz Dentária/diagnóstico por imagem , Dente/anatomia & histologia , Dente/diagnóstico por imagem , Arco Dental/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Modelos Lineares , Modelos Dentários , Projetos Piloto , Radiografia Panorâmica/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , São Francisco , Software
18.
J Clin Orthod ; 52(11): 604-20, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30462616

RESUMO

Distalization of mandibular molars has always been one of the most challenging treatment objectives in clinical orthodontics, particularly in adult patients.(1) If the posterior space is sufficient and alveolar bone is available, however, lower molar distalization is a viable option in Class III nonextraction therapy. Several intraoral appliances have been introduced for this purpose, including the lip bumper,(2,3) a distal extension lingual arch,(4) the Jones Jig,(*5) the Franzulum appliance,(6) and the multiloop edgewise archwire (MEAW),(7) Today, molars can be moved distally using miniscrew anchorage, with no need for patient cooperation, to camouflage a Class III malocclusion or relieve crowding without premolar extractions.


Assuntos
Má Oclusão Classe II de Angle , Desenho de Aparelho Ortodôntico , Adulto , Cefalometria , Humanos , Incisivo , Maxila , Fios Ortodônticos , Técnicas de Movimentação Dentária
19.
Proc Natl Acad Sci U S A ; 111(9): 3274-9, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-24344285

RESUMO

Agricultural production is sensitive to weather and thus directly affected by climate change. Plausible estimates of these climate change impacts require combined use of climate, crop, and economic models. Results from previous studies vary substantially due to differences in models, scenarios, and data. This paper is part of a collective effort to systematically integrate these three types of models. We focus on the economic component of the assessment, investigating how nine global economic models of agriculture represent endogenous responses to seven standardized climate change scenarios produced by two climate and five crop models. These responses include adjustments in yields, area, consumption, and international trade. We apply biophysical shocks derived from the Intergovernmental Panel on Climate Change's representative concentration pathway with end-of-century radiative forcing of 8.5 W/m(2). The mean biophysical yield effect with no incremental CO2 fertilization is a 17% reduction globally by 2050 relative to a scenario with unchanging climate. Endogenous economic responses reduce yield loss to 11%, increase area of major crops by 11%, and reduce consumption by 3%. Agricultural production, cropland area, trade, and prices show the greatest degree of variability in response to climate change, and consumption the lowest. The sources of these differences include model structure and specification; in particular, model assumptions about ease of land use conversion, intensification, and trade. This study identifies where models disagree on the relative responses to climate shocks and highlights research activities needed to improve the representation of agricultural adaptation responses to climate change.


Assuntos
Agricultura/economia , Mudança Climática , Produtos Agrícolas/crescimento & desenvolvimento , Modelos Econômicos , Dióxido de Carbono/análise , Comércio/estatística & dados numéricos , Simulação por Computador , Previsões , Humanos
20.
J Craniofac Surg ; 28(7): e599-e603, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28806378

RESUMO

BACKGROUND: Tooth movement out of anatomic limitations was assisted by augmented corticotomy using deproteinized bovine bone mineral. METHODS: Lip protrusion can be reduced by premolar extraction followed by retraction of the anterior teeth. Surgical intervention is appropriate when the alveolar bone housing of the anterior region is insufficient for the tooth movement. In this patient, corticotomy in upper palatal area and anterior segmented osteotomy in the mandible were performed. Anatomic limitation to the retraction was expanded by xenograft. An antero-posterior lingual appliance was used to bodily retract the upper anterior teeth. The gummy smile was resolved by intrusion of upper entire arch using 2 mid-palatal temporary skeletal anchorage devices. RESULTS: New bone formation was observed on palatal side of upper anterior teeth. The teeth were moved into augmented area without fenestration or vitality loss. Lip protrusion was resolved, and the gummy smile was effectively improved. CONCLUSIONS: Orthodontic tooth movement beyond the limitation of the alveolar bone housing can be achieved with surgical assistance, which can be performed under local anesthesia. Without orthognathic surgery, the gummy smile can be reduced using an antero-posterior lingual retractor with mid-palatal skeletal anchorage.


Assuntos
Procedimentos de Ancoragem Ortodôntica , Sorriso , Técnicas de Movimentação Dentária/métodos , Processo Alveolar/diagnóstico por imagem , Estética Dentária , Feminino , Humanos , Mandíbula/cirurgia , Maxila/cirurgia , Osteotomia , Palato/cirurgia , Técnicas de Movimentação Dentária/instrumentação , Adulto Jovem
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