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1.
IEEE Access ; : 1-1, 2023.
Artigo em Inglês | Scopus | ID: covidwho-20243873

RESUMO

As intelligent driving vehicles came out of concept into people’s life, the combination of safe driving and artificial intelligence becomes the new direction of future transportation development. Autonomous driving technology is developing based on control algorithms and model recognitions. In this paper, a cloud-based interconnected multi-sensor fusion autonomous vehicle system is proposed that uses deep learning (YOLOv4) and improved ORB algorithms to identify pedestrians, vehicles, and various traffic signs. A cloud-based interactive system is built to enable vehicle owners to master the situation of their vehicles at any time. In order to meet multiple application of automatic driving vehicles, the environment perception technology of multi-sensor fusion processing has broadened the uses of automatic driving vehicles by being equipped with automatic speech recognition (ASR), vehicle following mode and road patrol mode. These functions enable automatic driving to be used in applications such as agricultural irrigation, road firefighting and contactless delivery under new coronavirus outbreaks. Finally, using the embedded system equipment, an intelligent car was built for experimental verification, and the overall recognition accuracy of the system was over 96%. Author

2.
Transboundary and Emerging Diseases ; 2023, 2023.
Artigo em Inglês | Web of Science | ID: covidwho-20238770

RESUMO

Wild animals are considered reservoirs for emerging and reemerging viruses, such as the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Previous studies have reported that bats and ticks harbored variable important pathogenic viruses, some of which could cause potential diseases in humans and livestock, while viruses carried by reptiles were rarely reported. Our study first conducted snakes' virome analysis to establish effective surveillance of potential transboundary emerging diseases. Consequently, Adenoviridae, Circoviridae, Retroviridae, and Parvoviridae were identified in oral samples from Protobothrops mucrosquamatus, Elaphe dione, and Gloydius angusticeps based on sequence similarity to existing viruses. Picornaviridae and Adenoviridae were also identified in fecal samples of Protobothrops mucrosquamatus. Notably, the iflavirus and foamy virus were first reported in Protobothrops mucrosquamatus, enriching the transboundary viral diversity in snakes. Furthermore, phylogenetic analysis revealed that both the novel-identified viruses showed low genetic similarity with previously reported viruses. This study provided a basis for our understanding of microbiome diversity and the surveillance and prevention of emerging and unknown viruses in snakes.

3.
Cytotherapy ; 25(6 Supplement):E6-E7, 2023.
Artigo em Inglês | EMBASE | ID: covidwho-20238652

RESUMO

Background & Aim: The long-term effects of human mesenchymal stem cell (MSC) treatment on COVID-19 patients have not been fully characterized. The aim of this study was to evaluate the safety and efficacy of a MSC treatment administered to severe COVID-19 patients enrolled in a randomized, double-blind, placebo-controlled clinical trial (NCT 04288102). Methods, Results & Conclusion(s): A total of 100 patients experiencing severe COVID-19 received either MSC treatment (n = 65, 4x107 cells per infusion) or a placebo (n = 35) combined with standard of care on days 0, 3, and 6. Patients were subsequently evaluated 18 and 24 months after treatment to evaluate the long-term safety and efficacy of the MSC treatment. The outcomes measured included: 6-minute walking distance (6-MWD), lung imaging, quality of life according to the Short Form 36 questionnaire, COVID-19-related symptoms, titers of SARS-CoV-2 neutralizing antibodies, MSC-related adverse events (AEs), and tumor markers. Two years after treatment, a marginally smaller proportion of patients had a 6-MWD below the lower limit of the normal range in the MSC group than in the placebo group (OR = 0.19, 95% CI: 0.04-0.80, Fisher's exact test, p = 0.015). On the SF-36 questionnaire, a marginally higher general health score was received by the MSC group at month 18 compared with the placebo group (50.00 vs. 35.00;95% CI: 0.00-20.00, Wilcoxon rank sum test, p = 0.016). In contrast, there were no differences in the total severity score of lung imaging or the titer of neutralizing antibodies between the two groups. Meanwhile, there were no MSC-related AEs reported at the 18- or 24-month follow-ups. The serum levels of most of the tumor markers examined remained within normal ranges and were similar between the MSC and placebo groups. Long-term safety was observed for the COVID-19 patients who received MSC treatment. Yet few sustained efficacy of MSC treatment was observed at the end of the 2-year follow-up period. Funding(s): The National Key Research and Development Program of China (2022YFA1105604, 2020YFC0860900), the specific research fund of The Innovation Platform for Academicians of Hainan Province (YSPTZX202216) and the Fund of National Clinical Center for Infectious Diseases, PLA General Hospital (NCRCID202105,413FZT6). [Figure presented]Copyright © 2023 International Society for Cell & Gene Therapy

4.
ACM International Conference Proceeding Series ; : 141-145, 2023.
Artigo em Inglês | Scopus | ID: covidwho-20238650

RESUMO

The rise of Transportation Network Companies (TNCs) over the last decade has significantly disrupted the taxi industry. Studies have shown that taxi ridership has plummeted, and their capacity utilization rates are lower than 50% in five major U.S. cities. Additionally, the COVID-19 pandemic has dealt a severe blow to the already struggling taxi industry. To monitor the evolution of the taxi industry and its impacts on society, our study evaluates changes in the utilization rates, fuel consumption, and emissions among Chicago taxis, using taxi data with rich information on trip profiles from pre-pandemic and pandemic times. Our findings indicate that the taxi utilization rate decreased during the pandemic. While fuel consumption and emissions per kilometer decreased thanks to the reduced traffic during the pandemic, the overall fuel consumption and emissions increased due to increased deadhead travel. The methods developed in this study can be applied to monitor and evaluate the impact of future disruptive events on urban mobility and transportation systems more effectively. By utilizing mobility data to better understand transportation systems, we can develop more efficient, sustainable, and resilient mobility solutions for smart cities. © 2023 ACM.

5.
Clin Oncol (R Coll Radiol) ; 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: covidwho-20230982
7.
Medical Journal of Peking Union Medical College Hospital ; 12(1):5-8, 2021.
Artigo em Chinês | EMBASE | ID: covidwho-2322259

RESUMO

The global epidemic of coronavirus disease 2019 (COVID-19) is still growing. The response to this emerging disease should be considered with the context of its clinical characteristics and pathophysiological mechanisms. Although available therapeutic options are still very limited, current experience has suggested that the choice of clinical strategies should be based upon the disease stage and immune functions of the patients. The present article reviews the clinical characteristics of COVID-19 and current evidence of various treatment approaches. Combined with first-line experience, we summarize the current clinical strategies for COVID-19 management based on disease progress and staging.Copyright © 2021, Peking Union Medical College Hospital. All rights reserved.

8.
2022 IEEE/WIC/ACM International Joint Conference on Web Intelligence and Intelligent Agent Technology, WI-IAT 2022 ; : 782-787, 2022.
Artigo em Inglês | Scopus | ID: covidwho-2322024

RESUMO

The global pandemic Corona Virus Disease 2019 (COVID-19) has become one of the deadliest epidemics in human history, bringing enormous harm to human society. To help health policymakers respond to the threat of COVID-19, prediction of outbreaks is needed. Research on COVID-19 prediction usually uses data-driven models and mechanism models. However, in the early stages of the epidemic, there were not enough data to establish a data-driven model. The inadequate understanding of the virus that causes COVID-19, SARS-COV-2, has also led to the inaccuracies of the mechanism model. This has left the government with the toughest Non-pharmaceutical interventions (NPIs) to curb the spread of the virus, such as the lockdown of Wuhan in 2020. Yet man is a social animal, and social relations and interactions are necessary for his existence. The novel coronavirus and containment measures have challenged human and community interactions, affecting the lives of individuals and collective societies. To help governments take appropriate and necessary actions in the early stages of an epidemic, and to mitigate its impact on people's psychology and lives, we used the COVID-19 pandemic as an example to develop a model that uses surveillance data from one epidemic to predict the development trend of another. Based on the fact that both influenza and COVID-19 are transmitted through infectious respiratory droplets, we hypothesized that they may have the same underlying contact structure, and we proposed the influenza data-based COVID-19 prediction (ICP) model. In this model, the underlying contact pattern is firstly inferred by using a singular value decomposition method from influenza surveillance data. Then the contact matrix was used to simulate the influenza virus transmission through close contact of people, and the influenza virus transmission model was established. In order to be able to simulate the spread of COVID-19 virus using influenza transmission models, we used influenza contact matrix and COVID-19 infection data to estimate the risk of a population contracting COVID-19, i.e. force of infection of COVID-19. Finally, we used force of infection and influenza virus transmission model to simulate and predict the spread of COVID-19 in the population. We obtained age-disaggregated influenza and COVID-19 infection data for the United States in 2020, as well as data for Europe, which was not disaggregated by age. We use correlation coefficients as an evaluation indicator, and the final results prove that the predicted value and the actual value are positively correlated. So, the development trend of COVID-19 can be predicted using influenza surveillance data. © 2022 IEEE.

9.
Hepatology International ; 17(Supplement 1):S265-S266, 2023.
Artigo em Inglês | EMBASE | ID: covidwho-2327204

RESUMO

Background: Hepatocellular carcinoma (HCC) is the second leading cause of malignancy-related mortality and the fifth most common worldwide. Immuno-cancer microenvironment (ICME) was highlighted recently because scientists want to unlock the detailed mechanism in carcinogenesis pathway and find the novel interactions in ICME. Besides, single cell analysis could mitigate the interrupted signals between cells and tissues. On the other hand, COVID-19 angiotensin I converting enzyme (ACE) previously was reported associated with cancer. However, the robust association between COVID-19 and HCC ICME is still unaddressed. Aim(s): We plan to investigate the COVID-19 ACE relevant genes to HCC ICME regarding survival. Method(s): We used Reactome for COVID-19 ACE gene pathway mapping and explored the positive relevant gene expression. DISCO website was applied for single cell analyses using the above-collected genes from Reactome. Finally, we implanted the biomedical informatics into TIMER 2.0 for ICME survival analyses. Result(s): In Fig. 1, the gene-gene interaction mapping was shown. We collected 13 genes (CPB2, ACE2, AGT, MME, ANPEP, CPA3, ENPEP, GZMH, CTSZ, CTSD, CES1, ATP6AP2, and AOPEP) for further single cell relevant analyses, in Table 1, with detailed expression level (TPM). Among the above 13 genes, AGT, GZMH, CTSZ, CTSD, CES1, and ATP6AP2 were strongly expressed in liver tissue. We then applied the initial 13 genes to TIMER 2.0 for HCC ICME 2-year survival analyses. CPA3 and GZMH low expressions with high macrophage infiltration in HCC ICME showed significantly worse 2-year cumulative survival [hazard ratio (HR):CPA3 2.21, p-value 0.018;GZMH 2.07, p-value 0.0341]. ACE2, CPB2, AGT, MME, ANPEP, ENPEP, CTSZ, CTSD, CES1, and ATP6AP2 high expressions with high macrophage infiltration in HCC ICME revealed significantly worse 2-year cumulative survival. Conclusion(s): We demonstrate that ACE2 was strongly associated with HCC clinical survival with macrophage infiltration. However, the bidirectional translational roles about ACE2 relevant genes in HCC should be documented.

10.
Hepatology International ; 17(Supplement 1):S123, 2023.
Artigo em Inglês | EMBASE | ID: covidwho-2327134

RESUMO

Background/Aims: The clinical course of hepatitis B virus (HBV) infection in individuals with HIV-1 coinfection is marked by accelerated disease progression. A tenofovir-containing antiretroviral regimen is recommended in most people with HIV-1/HBV-coinfection, but there have not been randomized studies of tenofovir disoproxil fumarate (TDF) vs tenofovir alafenamide (TAF) in treatment- naive HIV-1/HBV-coinfected individuals. We report primary endpoint results from a Phase 3 study comparing bictegravir/emtricitabine/ TAF (B/F/TAF) vs dolutegravir + emtricitabine/TDF (DTG + F/TDF) at Week (W)48 in participants initiating treatment for both viruses. Method(s): Adults with HIV-1/HBV coinfection were randomized 1:1 to initiate blinded treatment with B/F/TAF or DTG + F/TDF (with placebo). Primary endpoints were the proportion of participants with HIV-1 RNA<50 copies/mL (FDA Snapshot) and plasma HBV DNA<29 IU/mL (missing = failure) at W48. Noninferiority was assessed with 95% CI (12% margin). Secondary and other endpoints included change from baseline cluster of differentiation 4 (CD4) count, proportion with hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) loss/seroconversion, and alanine transaminase (ALT) normalization (AASLD criteria). Result(s): Participants (N = 243) were randomized and treated (B/F/ TAF [n = 121], DTG + F/TDF [n = 122]) from 11 countries in Asia, Europe, North, and Latin America. Baseline characteristics were median age of 32 years, 4.5% female, 88% Asian, 30% HIV-1 RNA>100,000 c/mL, 40% CD4<200 cells/lL, median HBV DNA 8.1 log10 IU/mL, 78% HBeAg+. At W48, B/F/TAF was noninferior to DTG + F/TDF at achieving HIV-1 RNA<50 copies/mL (95% vs 91%, difference 4.1%;95% CI -2.5%-10.8%;P = 0.21), with mean CD4 gains of + 200 and + 175 cells/lL, respectively. B/F/TAF was superior to DTG + F/TDF at achieving HBV DNA<29 IU/mL (63% vs 43%, difference 16.6%;95% CI 5.9%-27.3%;P = 0.0023). Participants treated with B/F/TAF vs DTG + F/TDF had numerically higher HBsAg loss (13% vs 6%;P = 0.059), HBeAg loss (26% vs 14%;P = 0.055), HBeAg seroconversion (23% vs 11%;P = 0.031), and ALT normalization (73% vs 55%;P = 0.066). The most frequent adverse events among participants treated with B/F/TAF vs DTG + F/TDF were upper respiratory tract infection (17% vs 11%), COVID- 19 (13% vs 11%), pyrexia (9% vs 12%), ALT increase (7% vs 11%), and nasopharyngitis (11% vs 4%). ALT flares (elevations at >= 2 consecutive postbaseline visits) occurred in 11 participants (7 B/F/ TAF, 4 DTG + F/TDF), and all resolved. Conclusion(s): Among adults with HIV-1/HBV-coinfection starting antiviral therapy, both B/F/TAF and DTG + F/TDF had high HIV-1 suppression at year 1, with B/F/TAF resulting in superior HBV DNA suppression and significantly more HBeAg seroconversion. Safety findings were similar between groups.

11.
Topics in Antiviral Medicine ; 31(2):95, 2023.
Artigo em Inglês | EMBASE | ID: covidwho-2319250

RESUMO

Background: Omicron lineages, including BA.1 and BA.2, emerged following mass COVID-19 vaccination campaigns, displaced previous SARS-CoV-2 variants of concern worldwide, and gave rise to sublineages that continue to spread among humans. Previous research has shown that Omicron lineages exhibit a decreased propensity for lower respiratory tract (lung) infection compared to ancestral SARS-CoV-2, which may explain the decreased pathogenicity associated with Omicron infections. Nonetheless, Omicron lineages exhibit an unprecedented transmissibility in humans, which until now has been solely attributed to escape from vaccine-induced neutralizing antibodies. Method(s): We comprehensively analyzed BA1 and BA2 infection in primary human nasal epithelial cells cultured at the air-liquid interface, which recapitulates the physiological architecture of the nasal epithelium in vivo. Meanwhile we also took advantage of the VSV-based pseudovirus decorated with different Spike variants. Result(s): In primary human nasal epithelial cells cultured at the air-liquid interface, which recapitulates the physiological architecture of the nasal epithelium in vivo, BA.1 and BA.2 exhibited enhanced infectivity relative to ancestral SARS-CoV-2. Using VSV-based pseudovirus decorated with different Spike variants, we found that increased infectivity conferred by Omicron Spike is due to superior attachment and entry into nasal epithelial cells. In contrast to ancestral SARS-CoV-2, invasion of nasal epithelia by Omicron occurred via the cell surface and endosomal routes of entry and was accompanied by elevated induction of type-I interferons, indicative of a robust innate immune response. Furthermore, BA.1 was less sensitive to inhibition by the antiviral state elicited by type-I and type-III interferons, and this was recapitulated by pseudovirus bearing BA.1 and BA.2 Spike proteins. Conclusion(s): Our results suggest that the constellation of Spike mutations unique to Omicron allow for increased adherence to nasal epithelia, flexible usage of virus entry pathways, and interferon resistance. These findings inform our understanding of how Omicron evolved elevated transmissibility between humans despite a decreased propensity to infect the lower respiratory tract. Additionally, the interferon insensitivity of the Omicron Spike-mediated entry process may explain why Omicron lineages lost the capacity to antagonize interferon pathways compared to ancestral SARS-CoV-2.

12.
13.
Forests ; 14(3), 2023.
Artigo em Inglês | Scopus | ID: covidwho-2306026

RESUMO

In recent years, on-site visitation has been strictly restricted in many scenic areas due to the global spread of the COVID-19 pandemic. "Cloud tourism”, also called online travel, uses high-resolution photographs taken by unmanned aerial vehicles (UAVs) as the dominant data source and has attracted much attention. Due to the differences between ground and aerial observation perspectives, the landscape elements that affect the beauty of colored-leaved forests are quite different. In this paper, Qixia National Forest Park in Nanjing, China, was chosen as the case study area, and the best viewpoints were selected by combining tourists' preferred viewing routes with a field survey, followed by a scenic beauty evaluation (SBE) of the forests with autumn-colored leaves in 2021 from the aerial and ground perspectives. The results show that (1) the best viewpoints can be obtained through the spatial overlay of five landscape factors: elevation, surface runoff, slope, aspect, and distance from the road;(2) the dominant factors influencing the beauty of colored-leaved forests from the aerial perspective are terrain changes, forest coverage, landscape composition, landscape contrast, the condition of the human landscape, and recreation frequency;and (3) the beauty of the ground perspective of the colored-leaved forests is strongly influenced by the average diameter at breast height (DBH), the dominant color of the leaves, the ratio of the colored-leaved tree species, the canopy width, and the fallen leaf coverage. The research results can provide scientific reference for the creation of management measures for forests with autumn-colored leaves. © 2023 by the authors.

14.
Cognitive and Soft Computing Techniques for the Analysis of Healthcare Data ; : 101-121, 2022.
Artigo em Inglês | Scopus | ID: covidwho-2299049

RESUMO

The area of clinical decision support systems (CDSS) is facing a boost in research and development with the increasing amount of data in clinical analysis together with new tools to support patient care. This creates a vibrant and challenging environment for the medical and technical staff. This chapter presents a discussion about the challenges and trends of CDSS considering big data and patient-centered constraints. Two case studies are presented in detail. The first presents the development of a big data and AI classification system for maternal and fetal ambulatory monitoring, composed by different solutions such as the implementation of an Internet of Things sensors and devices network, a fuzzy inference system for emergency alarms, a feature extraction model based on signal processing of the fetal and maternal data, and finally a deep learning classifier with six convolutional layers achieving an F1-score of 0.89 for the case of both maternal and fetal as harmful. The system was designed to support maternal–fetal ambulatory premises in developing countries, where the demand is extremely high and the number of medical specialists is very low. The second case study considered two artificial intelligence approaches to providing efficient prediction of infections for clinical decision support during the COVID-19 pandemic in Brazil. First, LSTM recurrent neural networks were considered with the model achieving R2=0.93 and MAE=40,604.4 in average, while the best, R2=0.9939, was achieved for the time series 3. Second, an open-source framework called H2O AutoML was considered with the "stacked ensemble” approach and presented the best performance followed by XGBoost. Brazil has been one of the most challenging environments during the pandemic and where efficient predictions may be the difference in saving lives. The presentation of such different approaches (ambulatory monitoring and epidemiology data) is important to illustrate the large spectrum of AI tools to support clinical decision-making. © 2022 Elsevier Inc. All rights reserved.

15.
Data and Policy ; 4, 2022.
Artigo em Inglês | Scopus | ID: covidwho-2297102

RESUMO

In this article's Data Availability Statement, the URL to the replication code was missing. Find the full Data Availability Statement below along with the link to the openly available code on GitHub. Data Availability Statement. If possible, results of computed indicators or aggregated statistics will be made available through the website of the Gambia Bureau of Statistics (GBoS) or the Public Utilities Regulatory Authority (PURA). Details of methodologies employed for computing indicators can be found on the World Bank COVID19 Mobility Task Force Github repository. Code adjusted for running a system under PURA is maintained on the University of Tokyo's Spatial Data Commons Github repository and can be found here: https://github.com/SpatialDataCommons/CDR-wb-indicators-package. © The Author(s), 2023. Published by Cambridge University Press on behalf of Applied Probability Trust.

16.
China Oncology ; 32(6):499-511, 2022.
Artigo em Chinês | EMBASE | ID: covidwho-2263392

RESUMO

The corona virus disease 2019 (COVID-19) pandemic continues to severely impact healthcare systems around the world, and patients with cancer are even worse affected owing to compromised immune status and greater exposure risk. In the present review, we retrieved the relevant literature including guidelines and consensuses directly related to the purpose of this study from the PubMed database, and then summarized the research data on cancer and COVID-19, aiming to discuss the personal protection, systemic anti-cancer therapy, outcome of co-infection, and the clinical management strategy in this population. We found that patients with malignant tumors had a higher chance of suffering COVID-19, co-infection of whom had an even worse clinical prognosis, especially for those with lung cancer or hematologic cancers. Systemic chemotherapy may delay the clearance of severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) virus of human body, and thus have a negative impact on the clinical outcomes of COVID-19, while certain endocrine therapy and targeted drugs having limited or no impact. There has been no sufficient evidence for the impact of immune checkpoint therapy on the outcomes of COVID-19 till now. It is of great value to strengthen the personal protection of patients, adjust the anti-tumor treatments rationally and optimize the clinical management processes.Copyright © 2022, Editorial Office of China Oncology. All rights reserved.

17.
8th IEEE International Conference on Cloud Computing and Intelligence Systems, CCIS 2022 ; : 464-468, 2022.
Artigo em Inglês | Scopus | ID: covidwho-2269352

RESUMO

In this paper, we propose a new novel coronavirus pneumonia image classification model based on the combination of Transformer and convolutional network(VQ-ViCNet), and present a vector quantization feature enhancement module for the inconspicuous characteristics of lung medical image data. This model extracts the local latent layer features of the image through the convolutional network, and learns the deep global features of the image data through the Transformer's multi-head self attention algorithm. After the calculation of convolution and attention, the features learned by the Transformer Encoder are enhanced by the vector quantization feature enhancement module and able to better complete the final downstream tasks. This model performs better than convolutional architectures, pure attention architectures and generative models on all 6 public datasets. © 2022 IEEE.

18.
18th Annual ACM/IEEE International Conference on Human-Robot Interaction, HRI 2023 ; : 183-187, 2023.
Artigo em Inglês | Scopus | ID: covidwho-2268828

RESUMO

Self-disclosure to a social robot is a mental health intervention that can decrease stress for adolescents. Online digital robots provide the potential to scale this intervention especially in COVID-19 social distancing situations. However, self-disclosure interactions with digital social robots remain relatively unexplored. We conducted two online self-disclosure studies with adolescents (13-19 years old): our Active Listening Study compared experiences sharing positive, negative, and neutral feelings with a social robot, while our Journaling Study explored differences in sharing stressors by speaking with and without a social robot and by writing. We found that positive prompt tone improved mood while neutral prompt decreased stress, and less negative attitudes toward robots correlate with more qualitatively positive experiences with robot interactions.We also found robot disclosure interactions hold promising potential as a preferred method of self-disclosure over solo speaking, moderated by negative attitudes toward robots. This paper outlines limitations and future work from these studies. © 2023 IEEE Computer Society. All rights reserved.

19.
Remote Sensing ; 15(3), 2023.
Artigo em Inglês | Scopus | ID: covidwho-2268826

RESUMO

Agricultural intensification has resulted in the depletion of groundwater resources in many regions of the world. A prime example is Saudi Arabia, which witnessed dramatic agricultural expansion since the 1970s. To explore the influence of policy interventions aimed to better manage water resources, accurate information on the changes in the number and acreage of center-pivot fields is required. To quantify these metrics, we apply a hybrid machine learning framework, consisting of Density-Based Spatial Clustering of Applications with Noise, Convolutional Neural Networks, and Spectral Clustering, to the annual maximum Normalized Differential Vegetation Index maps obtained from Landsat imagery collected between 1990 to 2021. When evaluated against more than 28,000 manually delineated fields, the approach demonstrated producer's accuracies ranging from 83.7% to 94.8% and user's accuracies ranging from 90.2% to 97.9%. The coefficient of determination ((Formula presented.)) between framework-delineated and manually delineated fields was higher than 0.97. Nationally, we found that most fields pre-dated 1990 (covering 8841 km (Formula presented.) in that year) and were primarily located within the central regions covering Hail, Qassim, Riyadh, and Wadi ad-Dawasir. A small decreasing trend in field acreage was observed for the period 1990–2010. However, by 2015, the acreage had increased to approximately 33,000 fields covering 9310 km (Formula presented.). While a maximum extent was achieved in 2016, recent decreases have seen levels return to pre-1990 levels. The gradual decrease between 1990 to 2010 was related to policy initiatives designed to phase-out wheat, while increases between 2010 to 2015 were linked to fodder crop expansion. There is evidence of an agricultural uptick starting in 2021, which is likely in response to global influences such as the COVID-19 pandemic or the conflict in Ukraine. Overall, this work offers the first detailed assessment of long-term agricultural development in Saudi Arabia, and provides important insights related to production metrics such as crop types, crop water consumption, and crop phenology and the overarching impacts of agricultural policy interventions. © 2023 by the authors.

20.
AHURI Final Report ; (385)2022.
Artigo em Inglês | Scopus | ID: covidwho-2268822

RESUMO

Key points This analysis is based on data from the 2011 and 2016 censuses, and does not take into account the redistributions and changes that may have occurred with COVID-19. This report can be seen as providing a baseline for subsequent analysis of the changes that have occurred and continue to occur, identifying the trends and conditions across regional Australia's urban centres prior to 2020. Populations in regional urban centres are growing overall—however, this growth is differentiated. Regional urban centre population growth is associated with proximity to major cities, and to coastal locations. Regional urban centre population decline is associated with remoteness and exposure to the resource economy. Capital cities are the main source of migration to regional urban centres, principally coastal and satellite centres with regional-to-regional-centre migration highly self-contained. International migration follows similar distribution. Commuting between regional centres and proximate capital cities increased over 2011–2016, indicating increased peri-metropolitan dependency on metropolitan interactions. Employment growth is associated with population growth, particularly for the larger metropolitan satellite and coastal regional cities—however, this is also associated with lower wage growth due to the employment mix. Health, community service, construction, hospitality and accommodation increased their share of regional employment. Industries associated with agglomeration economies are concentrating in fewer urban centres, while those associated with population services are becoming more dispersed. National economic growth factors appear to expert greater influence on employment growth in regional urban centres, while industry factors exert very limited influence. Regional effects exert greater influence than industry effects, although these are unevenly distributed. In 135 of 198 cases, a regional urban centre exhibits employment growth along with its surrounding functional economic region. For 33 regional urban centres there is positive divergence, while for 25 there is negative divergence. Four regional urban centres are declining within a declining functional economic region. Factors associated with stronger employment growth include employment factors, industry factors (especially those dependent on population growth), while income growth was less associated with employment growth. Population change exerted a strong influence on employment growth, as did human capital factors. Housing market (i.e. price) growth is strongly associated with population growth, while locational factors exhibited low associations. Cluster analysis identified nine distinctive regional urban centre groups: metro-satellites;large regional cities;medium growth cities;regional service centres;ageing population centres;agricultural centres;mining centres;industrial centres, and northern Queensland centres. Policy development should consider the following: Policy and planning measures to address the phenomenon of growth in metropolitan satellite regional urban centres, and the need to ensure coherent population, housing and employment distribution and linkages. Coordinated economic and social development approaches to emerging low-income service economies in coastal regional urban centres. Long-term transition planning to address resource-dependent regional urban centres facing cyclical economic changes based on the labour intensity of construction relative to ongoing economic activity. Opportunities and mechanisms to leverage high-wage economic development from existing regional city industry clusters. Opportunities and mechanisms for regional spatial coordination of fiscal policy to optimise development of high-wage employment in suitable regional urban centres. The study Purpose The contribution of regional urban centres to Australia's economic and population growth has been a topic of growing policy interest in the past two decades, as a result of rapid growth in the major cities and concerns for parts of regiona Australia that have experienced population decline. Associated with these trends is the distribution of economic activity and employment—particularly as traditional regional strengths such as agriculture, manufacturing and mining have declined as sources of employment in recent decades. Over the same period, metropolitan areas have prospered because of concentrations of high-skill, high-wage knowledge work, indicating diverging regional fortunes as a result of wider economic trends. The purpose of this research is to investigate patterns and dynamics of population, migration and economic change in Australian regional urban centres 2011–2016. The research is principally an empirically focused investigation identifying patterns and dynamic processes of regional change using advanced spatial analytical techniques, but provides an information base that will support future policy development efforts. Inquiry This research is part of a wider AHURI Inquiry into population growth in Australia's smaller cities. The Inquiry asks two overarching questions: First, what is the capacity of Australia's smaller cities to assist in managing national population growth, including international and national migration? Second, which policy instruments and programs are most likely to redirect population movements to these locations? Study This research investigates two overarching questions related to the Inquiry: How can we differentiate Australia's regional urban centres according to economic profile, population trajectory, industry structure and geography? What are the current mobility and settlement patterns of migrants, including those arriving from other parts of Australia and from other nations, across these smaller cities? Three further research questions are posed by this project: 1. How can a typology of smaller cities assist to understand their role in regional, state and national economies? 2. How are Australia's regional urban centres differentiated in terms of economic profile, population trajectory and industry structure? 3. What demographic, economic and spatial factors are associated with economic and population growth, and what attributes are associated with better economic performance of regional urban centres? Approach and methods For Research question 1: the project undertakes longitudinal measures of social, demographic and industry change in regional cities 2011–2016 using Australian Bureau of Statistics (ABS) census data. Next, flow analysis and mapping of migration is applied to identify key migration patterns. Migration flows are used to construct migration regions via modularity analysis. Similar techniques are used to identify journey to work flows from which functional economic regions are constructed. Shift share of employment change and location quotient analysis of employment is used to understand economic change and industry structure. For Research question 2, to understand how Australia's regional urban centres are differentiated the project applies hierarchical cluster and discriminant analysis to construct a typology of regional urban centres. This is based on a combination of economic, demographic and geographic factors. These are compiled into summary data and descriptive explanations. For Research question 3: the study applies structural equation modelling (SEM) to identify the relationships between economic, social and demographic factors affecting population change and economic growth in regional urban centres. Key findings Differentiating Australia's regional urban centres Australia's regional urban centres are heterogeneous in terms of size, location within the Australian continent and settlement structures, level of employment, industrial mix and degree of interaction with regional, metropolitan, national and international economic processes and dynamics. In 2016, there were 198 Australian regional urban centres that had populations greater than 5,000 residents. Most are experiencing population growth. However this growth is differentiated across a range of factors, including: t e existing size of the centre location relative to the coast location relative to an existing major capital city. A small number of regional urban centres are experiencing population decline. These centres are largely associated with the resource economy. They are typically positioned in remote locations in Australia. Migration Migration is a major factor in population change within regional urban centres. Migration patterns are clearly structured at the regional scale, with distinct geographies of intra-regional movement that include discernible levels of self-containment. There is a sizeable phenomenon of major city to regional urban centre migration, especially in the south-east of Australia. Beyond the major metropolitan zones, there are larger internally connected migration regions, which often involving movement between adjacent regional urban centres. Some regional urban centres lose and receive populations across long distances. For example, the Northern Territory (NT) operates as a single migration region, partly because of its relatively small population and large scale—although the volumes of movement are relatively small. © Australian Housing and Urban Research Institute Limited 2022.

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