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1.
Nature ; 626(7999): 480, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38351335
3.
Artigo em Inglês | MEDLINE | ID: mdl-39101603

RESUMO

OBJECTIVES: The objective of this study is to assess accuracy, time-efficiency and consistency of a novel artificial intelligence (AI)-driven automated tool for cone-beam computed tomography (CBCT) and intraoral scan (IOS) registration compared with manual and semi-automated approaches. MATERIALS AND METHODS: A dataset of 31 intraoral scans (IOSs) and CBCT scans was used to validate automated IOS-CBCT registration (AR) when compared with manual (MR) and semi-automated registration (SR). CBCT scans were conducted by placing cotton rolls between the cheeks and teeth to facilitate gingival delineation. The time taken to perform multimodal registration was recorded in seconds. A qualitative analysis was carried out to assess the correspondence between hard and soft tissue anatomy on IOS and CBCT. In addition, a quantitative analysis was conducted by measuring median surface deviation (MSD) and root mean square (RMS) differences between registered IOSs. RESULTS: AR was the most time-efficient, taking 51.4 ± 17.2 s, compared with MR (840 ± 168.9 s) and SR approaches (274.7 ± 100.7 s). Both AR and SR resulted in significantly higher qualitative scores, favoring perfect IOS-CBCT registration, compared with MR (p = .001). Additionally, AR demonstrated significantly superior quantitative performance compared with SR, as indicated by low MSD (0.04 ± 0.07 mm) and RMS (0.19 ± 0.31 mm). In contrast, MR exhibited a significantly higher discrepancy compared with both AR (MSD = 0.13 ± 0.20 mm; RMS = 0.32 ± 0.14 mm) and SR (MSD = 0.11 ± 0.15 mm; RMS = 0.40 ± 0.30 mm). CONCLUSIONS: The novel AI-driven method provided an accurate, time-efficient, and consistent multimodal IOS-CBCT registration, encompassing both soft and hard tissues. This approach stands as a valuable alternative to manual and semi-automated registration approaches in the presurgical implant planning workflow.

5.
Nature ; 543(7645): 367-372, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28300094

RESUMO

Successful delivery of the United Nations sustainable development goals and implementation of the Paris Agreement requires technologies that utilize a wide range of minerals in vast quantities. Metal recycling and technological change will contribute to sustaining supply, but mining must continue and grow for the foreseeable future to ensure that such minerals remain available to industry. New links are needed between existing institutional frameworks to oversee responsible sourcing of minerals, trajectories for mineral exploration, environmental practices, and consumer awareness of the effects of consumption. Here we present, through analysis of a comprehensive set of data and demand forecasts, an interdisciplinary perspective on how best to ensure ecologically viable continuity of global mineral supply over the coming decades.

6.
Pure Appl Geophys ; 180(1): 383-404, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36590883

RESUMO

This article examines the role of the meteorological variable in the spread of the ongoing pandemic coronavirus disease 2019 (COVID-19) across India. COVID-19 has created an unprecedented situation for public health and brought the world to a standstill. COVID-19 had caused more than 1,523,242 deaths out of 66,183,029 confirmed cases worldwide till the first week of December 2020. We have examined the surface temperature, relative humidity, and rainfall over five cities: Delhi, Mumbai, Kolkata, Bengaluru, and Chennai, which were severely affected by COVID-19. It is found that the prevailing southwest (SW) monsoon during the pandemic has acted as a natural sanitizer in limiting the spread of the virus. The mean rainfall is ~ 20-40 mm over the selected cities, resulting in an average decrease in COVID cases by ~ 18-26% for the next 3 days after the rainfall. The day-to-day variations of the meteorological parameters and COVID-19 cases clearly demonstrate that both surface temperature and relative humidity play a vital role in the indirect transport of the virus. Our analysis reveals that most COVID-19 cases fall within the surface temperature range from 24 to 30 °C and relative humidity range from 50% to 80%. At a given temperature, COVID-19 cases show a large dependency on the relative humidity; therefore, the coastal environments were more prone to infections. Wavelet transforms coherence analysis of the daily COVID-19 cases with temperature and relative humidity reveals a significant coherence within 8 days.

7.
Environ Sci Technol ; 56(22): 15280-15289, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36288723

RESUMO

Significant amounts of feedstock metals will be required to build the infrastructure for the green energy transition. It is currently estimated, however, that the world may be facing an "infrastructure gap" that could prevent us from meeting United Nations Sustainable Development Goal targets. Prior investigations have focused on the extractive aspects of the mining industry to meet these targets and on looming bottlenecks and regional challenges in these upstream market segments. Scant attention has been paid to the downstream processing segments of the raw materials value chain, which also has a high degree of market concentration. Growing international tensions and geopolitical events have resulted in a shift toward "reshoring" and "near-shoring" of mining processing capabilities as regional powers attempt to make metal supply chains more secure. While increasing resilience, these shifts can also dilute the overall effectiveness of the global mining supply network and subsequently hamper the world's ability to close the green energy infrastructure gap. We argue that broadening the remit of the International Renewable Energy Agency (IRENA) to include coordinating these mission-critical metal processing functions can mitigate these issues. The G20 is one potential forum for enabling an integrated mineral processing agreement under the auspices of IRENA.


Assuntos
Minerais , Energia Renovável
8.
Adv Exp Med Biol ; 1289: 107-114, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32661841

RESUMO

Tooth root resorption is an unwanted result of orthodontic tooth movement, and it can be expressed by a reduction in cementum thickness. The aim of this experimental study was to evaluate the effect of intraligamentary injection of osteogenic-induced gingival fibroblasts (OIGF) on cellular and acellular tooth root cementum thickness in modeled orthodontic tooth movement. Six beagle dogs were used in the study. All the upper and lower third and fourth premolars were subjected to mechanical loading for 4 weeks, which induced orthodontic tooth movement. Fifteen premolars were assigned to the OIGF group, which received a single OIGF injection through the periodontal ligament near the root apex (n = 7 teeth), and to the control group, which received a single injection of Dulbecco's modified eagle's medium in the periapical area (n = 8 teeth). The evaluation of histomorphometry was performed to assess the thicknesses of cellular and acellular cementum at the root apex and four bilateral sites distal to the apex. We found no statistically significant enhancing effects of gingival fibroblasts on either cellular or acellular cementum thicknesses when compared with the control group. We conclude that a single intraligamentary injection of OIGF does not stimulate the formation of tooth root cementum in the dog model of orthodontic tooth movement. Thus, OIGF is unlikely to prevent orthodontic-induced tooth root resorption.


Assuntos
Reabsorção da Raiz , Animais , Dente Pré-Molar , Cemento Dentário , Cães , Fibroblastos , Reabsorção da Raiz/etiologia , Técnicas de Movimentação Dentária/efeitos adversos
10.
Proc Biol Sci ; 285(1892)2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-30518573

RESUMO

Mining poses serious and highly specific threats to biodiversity. However, mining can also be a means for financing alternative livelihood paths that, over the long-term, may prevent biodiversity loss. Complex and controversial issues associated with mining and biodiversity conservation are often simplified within a narrow frame oriented towards the negative impacts of mining at the site of extraction, rather than posed as a series of challenges for the conservation science community to embrace. Here, we synthesize core issues that, if better understood, may ensure coexistence between mining and conservation agendas. We illustrate how mining impacts biodiversity through diverse pathways and across spatial scales. We argue that traditional, site-based conservation approaches will have limited effect in preventing biodiversity loss against an increasing mining footprint, but opportunities to improve outcomes (e.g. through long-term strategic assessment and planning) do exist. While future mineral supply is uncertain, projections suggest demand will grow for many metals and shift mining operations towards more dispersed and biodiverse areas. Initiating dialogue between mining companies, policy-makers and conservation organizations is urgent, given the suite of international agendas simultaneously requiring more minerals but less biodiversity loss.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Mineração , Projetos de Pesquisa/tendências , Animais , Política Ambiental/legislação & jurisprudência , Política Ambiental/tendências , Projetos de Pesquisa/normas
11.
Proc Natl Acad Sci U S A ; 111(21): 7576-81, 2014 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-24821758

RESUMO

Sustainability science has grown as a field of inquiry, but has said little about the role of large-scale private sector actors in socio-ecological systems change. However, the shaping of global trends and transitions depends greatly on the private sector and its development impact. Market-based and command-and-control policy instruments have, along with corporate citizenship, been the predominant means for bringing sustainable development priorities into private sector decision-making. This research identifies conflict as a further means through which environmental and social risks are translated into business costs and decision making. Through in-depth interviews with finance, legal, and sustainability professionals in the extractive industries, and empirical case analysis of 50 projects worldwide, this research reports on the financial value at stake when conflict erupts with local communities. Over the past decade, high commodity prices have fueled the expansion of mining and hydrocarbon extraction. These developments profoundly transform environments, communities, and economies, and frequently generate social conflict. Our analysis shows that mining and hydrocarbon companies fail to factor in the full scale of the costs of conflict. For example, as a result of conflict, a major, world-class mining project with capital expenditure of between US$3 and US$5 billion was reported to suffer roughly US$20 million per week of delayed production in net present value terms. Clear analysis of the costs of conflict provides sustainability professionals with a strengthened basis to influence corporate decision making, particularly when linked to corporate values. Perverse outcomes of overemphasizing a cost analysis are also discussed.


Assuntos
Relações Comunidade-Instituição/economia , Conflito Psicológico , Conservação dos Recursos Naturais/métodos , Meio Ambiente , Indústrias Extrativas e de Processamento/economia , Corporações Profissionais/estatística & dados numéricos , Risco , Indústrias Extrativas e de Processamento/métodos , Humanos , Entrevistas como Assunto
12.
Nat Mater ; 17(12): 1052-1053, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30470833
13.
Science ; 385(6712): 940, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39208113

RESUMO

A policy pioneer's memoir shows how climate science penetrated the defense sector.

14.
Science ; 383(6681): 374, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38271501

RESUMO

A journalist probes tensions surrounding two minerals that are key to green technologies.

15.
Sci Total Environ ; 954: 176629, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39362543

RESUMO

Knowledge of variation in the percentage occurrence of the cirrus clouds (POC) during transient monsoon conditions is essential for understanding the role of the monsoon in transporting the water vapor into the lower stratosphere which is vital in quantifying the radiation budget of the earth-atmosphere system. In this paper, we present the spatial structure of the POC, the geometrical properties such as cloud top and base height (CTH & CBH), cloud thickness (CTH-CBH), optical properties such as optically thick, thin, and subvisible cirrus clouds during the active and break phases of the Asian summer monsoon using Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) during July-August 2006-2018. The active and break phases are identified based on the central India rainfall from the India Meteorological Department dataset. The POC is found to be higher by 10-30 % over central India and some parts of the eastern Arabian Sea (AS) and Bay of Bengal (BoB) during the active phase compared to the break phase which shows enhancement in POC over the foothill of Himalaya and southern part of BoB and AS. The higher POC is attributed to the increase in the convective activities associated with the increase in tropical easterly jet during the active phase. The CTH and CBH range ~14-18 km and 12-16 km, respectively during the active phase compared to the break phase. The contributions of optically thick and thin clouds are higher in POC during both phases compared to subvisible clouds. Both convectively generated and in situ-formed cirrus clouds dominate during the active phase compared to the break phase indicating the dominance of the freeze-drying processes during the active phase.

16.
Sci Rep ; 14(1): 369, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172136

RESUMO

The process of creating virtual models of dentomaxillofacial structures through three-dimensional segmentation is a crucial component of most digital dental workflows. This process is typically performed using manual or semi-automated approaches, which can be time-consuming and subject to observer bias. The aim of this study was to train and assess the performance of a convolutional neural network (CNN)-based online cloud platform for automated segmentation of maxillary impacted canine on CBCT image. A total of 100 CBCT images with maxillary canine impactions were randomly allocated into two groups: a training set (n = 50) and a testing set (n = 50). The training set was used to train the CNN model and the testing set was employed to evaluate the model performance. Both tasks were performed on an online cloud-based platform, 'Virtual patient creator' (Relu, Leuven, Belgium). The performance was assessed using voxel- and surface-based comparison between automated and semi-automated ground truth segmentations. In addition, the time required for segmentation was also calculated. The automated tool showed high performance for segmenting impacted canines with a dice similarity coefficient of 0.99 ± 0.02. Moreover, it was 24 times faster than semi-automated approach. The proposed CNN model achieved fast, consistent, and precise segmentation of maxillary impacted canines.


Assuntos
Aprendizado Profundo , Dente Impactado , Humanos , Tomografia Computadorizada de Feixe Cônico/métodos , Dente Canino/diagnóstico por imagem , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador/métodos
18.
Nat Commun ; 14(1): 1393, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36914636

RESUMO

In the context of natural resource degradation, migration can act as means of adaptation both for those leaving and those supported by remittances. Migration can also result from an inability to adapt in-situ, with people forced to move, sometimes to situations of worse or of the same exposure to environmental threats. The deleterious impacts of resource degradation have been proposed in some situations to limit the ability to move. In this contribution, we use remote sensed information coupled with population density data for continental Africa to assess quantitatively the prevalence of migration and immobility in the context of one cause of resource degradation: drought. We find that the effect of drought on mobility is amplified with the frequency at which droughts are experienced and that higher income households appear more resilient to climatic shocks and are less likely to resort to mobility as an adaptation response.


Assuntos
Características da Família , Renda , Humanos , África , Conservação dos Recursos Naturais , Recursos Naturais , Secas
19.
Cureus ; 15(10): e46435, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37927697

RESUMO

INTRODUCTION: Nasal carriage of Staphylococcus species plays an important role in the epidemiology and pathogenesis of both community and healthcare-associated infections. Coinciding the emergence of methicillin-resistant Staphylococcus aureus (MRSA) is a challenge for clinicians to prevent their spread. Mupirocin is a topical antimicrobial agent approved for eradicating nasal carriage of staphylococcal species in adult patients and healthcare workers (HCWs). The increasing prevalence of mupirocin resistance among Staphylococcus aureus and coagulase-negative staphylococci species could be an important threat to the future use of mupirocin against MRSA. OBJECTIVE: The aim of this study is to determine the prevalence of MRSA from nasal swabs of HCWs in intensive care units and its level of resistance pattern of mupirocin in all isolates of Staphylococcus species by disk diffusion and epsilometer test (E-test) and to determine post decolonization screening. MATERIALS AND METHODS:  A total of 67 HCWs (doctors, nursing staff, technicians, and housekeeping staff) in the medical and surgical intensive care units were included in the study. Nasal swabs were collected from the subjects and cultured onto nutrient and blood agar, which were then incubated at 37ºC for 18 to 24 hours. Staphylococcus aureus and coagulase-negativeStaphylococcus species (CoNS) were identified by standard biochemical techniques. Methicillin resistance was detected by the disk diffusion method using a 30 µg cefoxitin disk as per the Clinical and Laboratory Standards Institute (CLSI) guidelines, and mupirocin resistance was detected using a 5 µg mupirocin disk. The resistance strains were further subjected to E-strip testing to determine the level of mupirocin resistance. RESULTS:  A total of 72 isolates were grown from the 67 subjects used in this study. Nine strains (12.5%) grew S. aureus, and 52 strains (72.2%) grew CoNS. Methicillin resistance was seen in five isolates (6.9%) of S. aureus and 45 isolates (62.5%) of CoNS. Mupirocin resistance was seen in 11 isolates of methicillin-resistant coagulase-negative Staphylococcus species (MRCoNS), where three isolates (4.1%) showed low-level mupirocin resistance MuL and eight isolates (11.11%) showed high-level mupirocin resistance MuH. None of the isolates of MRSA, methicillin-sensitive Staphylococcus aureus (MSSA), and methicillin-sensitive coagulase-negative Staphylococcusspecies (MSCoNS) were resistant to mupirocin. Seven out of nine HCWs (77.8%) showed clearance of the organism after decolonization therapy. CONCLUSION: The prevalence of emerging resistance to mupirocin in MRSA and MRCoNS is of great concern, especially in the nasal carrier state of HCWs. Hence, methicillin and mupirocin resistance in S. aureus and CoNS must be detected in HCWs as a routine protocol, and decolonization measures should be undertaken to prevent healthcare-associated infections.

20.
Stud Health Technol Inform ; 299: 202-207, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36325864

RESUMO

Anti-Microbial Resistance is one of the greatest threats that mankind faces right now due to the inappropriate use of antibiotics. Institution of appropriate antibiotics in right dose for the right patient at right time is the "gamechanger" in fighting AMR. Antibiotic Sensitivity Testing (AST) or antibiogram is done to ascertain the sensitivity profile of the organism. The most widely used method in laboratory practice in India is the Kirby-Bauer's disk diffusion test. There are few shortcomings in the manual interpretation of antibiograms in the form of high inter-operator variability, mandatory requirement of trained microbiologists - which is difficult in low-resource settings and high degree of interpersonal bias due to various factors like stress, workload, and visual acuity. We propose the Ab.ai tool for automating the AST procedures in laboratory. The Ab.ai tool comprises of 3 phases: first for data collection, second for data processing and the third for generation of antibiotic sensitivity reports. Various software packages like OpenCV and EasyOCR are used for the development of the Ab.ai tool. A total of 50 antibiograms of both GPC and GNB are interpreted both by manual and automated method. The manual method is considered the "gold-standard" and the performance of Ab.ai tool was compared against the manual method. The Ab.ai tool achieved an agreement of 98.4% on susceptibility categorization of GPC antibiotics and 97.6% on that of GNB antibiotics against the gold standard manual method. The proposed Ab.ai tool serves as a perfect candidate for automating AST procedures and would prove to be a "game-changer" in battling AMR.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Inteligência Artificial , Índia
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