46 research outputs found
A Novel Macroscopic Dynamic Loading Model and its Properties
Existing macroscopic dynamic loading models (Linear travel time, Divided linear
travel time and Point-Queue models), which are based on representation of link
properties as a whole and fully comply with the requirements of the dynamic traffic
assignment (DTA) procedure, are widely used in many DTA studies. This is because of
their lower implementation and computational costs. DTA literature consistently
suggesting alternative models but many of them do not comply with the required
properties for their use in DTA and if the model fulfils these requirements, the
computational and implementation issues in these models are such demanding that their
general use is very limited (e.g. Cell Transmission model). This paper presents a novel
model (Adnan-Fowkes model), which utilise the similar modelling framework through
which Point-Queue model was developed and at the same time addresses the drawbacks
exist in the Point-Queue and Liner travel time models which are due to their simple
mathematical formulation. The proposed model is developed with a simple mathematical
construction and it is as easy to implement as Point-Queue and Linear travel time
models. The paper comprehensively discusses the properties which are desirable for the
use of any model in DTA and analytically illustrates that the Adnan-Fowkes model is
successfully fulfilling all these requirements. Numerical experiments are also conducted
for comparison of the behaviour of the Adnan-Fowkes model along with the Point-Queue
and Linear travel time models. The results of these experiments provide more useful
insight for the Adnan-Fowkes model and support the characteristics of this model which
are mentioned analytically in earlier sections of this paper
Awareness of using Radiology in Diagnosing COVID-19 among Radiological Students
The coronavirus (COVID-2019) has spread very rapidly over many countries around the world, producing an outbreak of acute infectious pneumonia. Medical imaging devices play a vital role in early diagnosis, evaluating severity and disease prognosis of confirmed patients with COVID-19. The aim of the study is to evaluate the awareness level of radiology students about COVID-19 and their understanding of the role of radiology devices in diagnosing COVID-19. An online cross-sectional questionnaire was conducted. Seventy-one students participated in this study. This study showed that students were properly aware of the basic knowledge of the COVID-19, 87 % of the students believed that radiology had an important role in diagnosing COVID-19. In addition, 50% of the students believed that CT was the most important modality in diagnosing COVID-19 and 32.35% believed that x-ray was the most important one. Lack of knowledge was found regarding the biomarkers that appear in radiological images in patients with COVID-19. 66.18 % of the students acquired the knowledge from their study in the radiology field and from social media (Twitter). The level of awareness among radiology students is high. There were two main reasons for this high level of awareness: gained education and social media, especially Twitter. The outbreak of the COVID-19 was not only about its health effects but also how the population persevered this pandemic. However, this level of awareness tended to be lower when discussing detailed findings of radiological images such as detailed biomarkers
Human resource development : training and development practices and related organisational factors in Kuwaiti organisations.
This study examines and aims to disclose the current policies and practices of Training and Development (T&D) within Kuwaiti government and private/joint-venture organisations. The literature review indicates that although much attention has been devoted in studying Training and Development practices, a very few focus on T&D related factors on organisation performance in developing countries. The literature also indicates the need for considering these factors in order to have a better T&D effectiveness, and hence organisation overall performance. In this study the Training for Impact model was adopted and tested within Kuwaiti context in terms of training needs assessment and evaluation and follow-up. This research uses data collected from 100 organisations in Kuwait. 50 of these were government and 50 private /joint venture listed in Kuwait Stock Exchange. Therefore, all managers (100 training personnel) who are in charge of T&D function/programmes, were samples of the respondents of the present study. The main data collection methods adopted by this study were interviews (semi-structured) and "drop-in and pick-up" self-completion questionnaires. The data were quantitatively analysed and triangulation of quantitative findings was carried out in order to find out the difference between the two sectors in Kuwait in terms of T&D practices and related factors. To establish a causal connection between related factors and identified dimensions (T&D effectiveness, organisational rating, and satisfaction with evaluation process), a multiple regression technique was employed. The major findings of this study are noted below: Results indicate that the majority of the investigated organisations do not have a formal T&D system. T&D programmes are still carried out on a piecemeal basis rather than a systematic long-term policy. Findings which were common among the majority of the approached organisations were absence of a systematic organisational training needs analysis, use of conventional training methods, lack of effective procedures for T&D evaluation. The study explores the training personnel's way of thinking towards their T&D function and to the proposed T&D dimensions framework (integrated HRD strategy, top and line management commitment, a supportive formal system, T&D mechanism, organisational culture, and training budget). The findings indicate that most of the training personnel perceived these dimensions as providing motivation, commitment and support to their T&D function. Six main factors were found to influence T&D practices in government and private/joint venture organisations. These factors are: top management commitment, mutual support between organisational philosophy and T&D activities, line management support T&D involvement in organisation strategy, T&D policies and plans, and T&D effects on employees self-development. The study also identifies T&D effects on organisation performance in Kuwaiti organisations in terms of eliminating problems; increasing commitment and motivation; fulfilling individual needs and personal objectives, improving interpersonal and interdepartmental relations, improving quality of goods and services; and leading to effective utilisation and investment in human resources. In addition the study establishes a causal connection of T&D related factors with performance dimensions, organisation rating, and satisfaction of T&D evaluation. The author recommends that for the T&D function to be treated as seriously as other organisational functions, then Kuwaiti training personnel, as well as top and line management, need to be more willing to play proactive and strategic organisational roles in T&D activities
The effects of free amino acids profiles on seeds germination/dormancy and seedlings development of two genetically different cultivars of Yemeni Pomegranates
Plant seeds used rely on a wide range of internal mechanisms and physio-chemical factors to ensure their germination under favorable environmental conditions. Most plant seeds have complex process of germination, including water, oxygen, temperature availability, genome-wide gene expression, signal transduction, hormones stimulations, inhibitors removal and catalytic protein synthesis. In addition, influences of seeds nutrient values such as, protein, lipids, sugars and free amino acids have a special importance. Regarding, seeds free amino acids. Discussion of these individual factors needs to be put in context of their role in germination processes. Regarding, free amino acids seed storage, there is limited information about their relevant functions in activation and/or deactivation of required metabolic mechanisms and interactive compounds involved in this process in commercial plant cultivars. Therefore, current study was aimed to determine the probable influence of free amino acid compositions of seeds on germination process of two different (Punica granatum L.) pomegranate cultivars including wild type Automi cultivar and edible Khazemi cultivar. In particular, we focused on the impact of amino acids contents variations on germination process and associated AAs compositional changes during various stages of germination and seedlings establishment. Amino acid analysis using HPLC detected all the essential and non-essential amino acids in the raw seeds of the studied cultivars, Automi and Khazemi along with AAs compositional changes occurred during different stages of seed germination. These AAs have been extensively analyzed in the context of their role in dormancy breaking capacities in plants species. Automi raw seeds are rich in Phe, that, is strongly related to ABA synthesis and hence might be responsible for the dormancy of Automi seeds, Khazemi raw seeds have sufficient levels of Arg, Glu and Met that have been reported to enhance seeds germination in plant, therefore Khazemi germination capacity was assumed to be regulated more or less by these AAs. In addition, changes in amino acid composition in the germinated Khazemi cultivar during various stages of seeds germination including imbibition, germination, and sprouts stages have been noticed to change in response with germination demands. This suggests that amino acids reserves in dry seeds are major determinant for germination capacity and germination behavior in the following steps of germination. The noticed particular AAs increase/decrease along the time course of Khazemi pomegranate germination till establishment of heterotrophic seedlings were used as cornerstones for elucidation and deduction of putative function and relevant biochemical pathways controlling initiation of seeds germination and seedlings developments. Based on publicly available databases of model plants and literatures surveys, we established correlations between prevailing AAs factors as biochemical parameters actively involved in seeds dormancy-breaking and germination process
CERES-maize model for determining the optimum planting dates of early maturing maize varieties in northern Nigeria
Open Access JournalField trials were carried out in the Sudan Savannah of Nigeria to assess the usefulness of CERES–maize crop model as a decision support tool for optimizing maize production through manipulation of plant dates. The calibration experiments comprised of 20 maize varieties planted during the dry and rainy seasons of 2014 and 2015 at Bayero University Kano and Audu Bako College of Agriculture Dambatta. The trials for model evaluation were conducted in 16 different farmer fields across the Sudan (Bunkure and Garun—Mallam) and Northern Guinea (Tudun-Wada and Lere) Savannas using two of the calibrated varieties under four different sowing dates. The model accurately predicted grain yield, harvest index, and biomass of both varieties with low RMSE-values (below 5% of mean), high d-index (above 0.8), and high r-square (above 0.9) for the calibration trials. The time series data (tops weight, stem and leaf dry weights) were also predicted with high accuracy (% RMSEn above 70%, d-index above 0.88). Similar results were also observed for the evaluation trials, where all variables were simulated with high accuracies. Estimation efficiencies (EF)-values above 0.8 were observed for all the evaluation parameters. Seasonal and sensitivity analyses on Typic Plinthiustalfs and Plinthic Kanhaplustults in the Sudan and Northern Guinea Savannas were conducted. Results showed that planting extra early maize varieties in late July and early maize in mid-June leads to production of highest grain yields in the Sudan Savanna. In the Northern Guinea Savanna planting extra-early maize in mid-July and early maize in late July produced the highest grain yields. Delaying planting in both Agro-ecologies until mid-August leads to lower yields. Delaying planting to mid-August led to grain yield reduction of 39.2% for extra early maize and 74.4% for early maize in the Sudan Savanna. In the Northern Guinea Savanna however, delaying planting to mid-August resulted in yield reduction of 66.9 and 94.3% for extra-early and early maize, respectively
Options for calibrating ceres-maize genotype specific parameters under data-scarce environments
Open Access JournalMost crop simulation models require the use of Genotype Specific Parameters (GSPs) which provide the Genotype component of G×E×M interactions. Estimation of GSPs is the most difficult aspect of most modelling exercises because it requires expensive and time-consuming field experiments. GSPs could also be estimated using multi-year and multi locational data from breeder evaluation experiments. This research was set up with the following objectives: i) to determine GSPs of 10 newly released maize varieties for the Nigerian Savannas using data from both calibration experiments and by using existing data from breeder varietal evaluation trials; ii) to compare the accuracy of the GSPs generated using experimental and breeder data; and iii) to evaluate CERES-Maize model to simulate grain and tissue nitrogen contents. For experimental evaluation, 8 different experiments were conducted during the rainy and dry seasons of 2016 across the Nigerian Savanna. Breeder evaluation data were also collected for 2 years and 7 locations. The calibrated GSPs were evaluated using data from a 4-year experiment conducted under varying nitrogen rates (0, 60 and 120kg N ha-1). For the model calibration using experimental data, calculated model efficiency (EF) values ranged between 0.88–0.94 and coefficient of determination (d-index) between 0.93–0.98. Calibration of time-series data produced nRMSE below 7% while all prediction deviations were below 10% of the mean. For breeder experiments, EF (0.58–0.88) and d-index (0.56–0.86) ranges were lower. Prediction deviations were below 17% of the means for all measured variables. Model evaluation using both experimental and breeder trials resulted in good agreement (low RMSE, high EF and d-index values) between observed and simulated grain yields, and tissue and grain nitrogen contents. It is concluded that higher calibration accuracy of CERES-Maize model is achieved from detailed experiments. If unavailable, data from breeder experimental trials collected from many locations and planting dates can be used with lower but acceptable accuracy
Optimizing sowing density-based management decisions with different nitrogen rates on smallholder maize farms in northern Nigeria
Open Access Article; Published online: 18 Jan 2021In this study, the CERES-Maize model was calibrated and evaluated using data from 60 farmers’ fields across Sudan (SS) and Northern Guinea (NGS) Savannas of Nigeria in 2016 and 2017 rainy seasons. The trials consisted of 10 maize varieties sown at three different sowing densities (2.6, 5.3, and 6.6 plants m−2) across farmers’ field with contrasting agronomic and nutrient management histories. Model predictions in both years and locations were close to observed data for both calibration and evaluation exercises as evidenced by low normalized root mean square error (RMSE) (≤15%), high modified d-index (> 0.6), and high model efficiency (>0.45) values for the phenology, growth, and yield data across all varieties and agro-ecologies. In both years and locations and for both calibration and evaluation exercises, very good agreements were found between observed and model-simulated grain yields, number of days to physiological maturity, above-ground biomass, and harvest index. Two separate scenario analyses were conducted using the long-term (26 years) weather records for Bunkure (representing the SS) and Zaria (representing the NGS). The early and extra-early varieties were used in the SS while the intermediate and late varieties were used in the NGS. The result of the scenario analyses showed that early and extra-early varieties grown in the SS responds to increased sowing density up to 8.8 plants m−2 when the recommended rate of N fertilizers (90 kg N ha−1) was applied. In the NGS, yield responses were observed up to a density of 6.6 plants m−2 with the application of 120 kg N ha−1 for the intermediate and late varieties. The highest mean monetary returns to land (US957.7 ha−1) was simulated for scenarios with 6.6 plants m−2 and 90 Kg N ha−1 in the SS. In the NGS, monetary return per hectare was highest with a planting density of 6.6 plants m−2 with the application of 120 kg N, while the return to labor was highest for sowing density of 5.3 plants m−2 at the same N fertilizer application rates. The results of the long-term simulations predicted increases in yield and economic returns to land and labor by increasing sowing densities in the maize belts of Nigeria without applying N fertilizers above the recommended rates
A review on nanocellulosic fibres as new material for sustainable packaging: process an applications
The demand for exploring advanced and eco-friendly sustainable packaging materials with superior physical, mechanical and barrier properties is increasing. The materials that are currently used in packaging for food, beverage, medical and pharmaceutical products, as well as in industrial applications, are non-degradable, and thus, these materials are raising environmental pollution concerns. Numerous studies have been conducted on the utilization of bio-based materials in the pursuit of developing sustainable packaging materials. Although significant improvements have been achieved, a balance among environmental concerns, economic considerations and product packaging performance is still lacking. This is likely due to bio-based materials being used in product packaging applications without a proper design. The present review article intends to summarize the information regarding the potential applications of cellulosic nanofiber for the packaging. The importance of the design process, its principles and the challenges of design process for sustainable packaging are also summarized in this review. Overall it can be concluded that scientists, designers and engineers all are necessarily required to contribute towards research in order to commercially exploit cellulose nanofiber for sustainable packaging
The global burden of cancer attributable to risk factors, 2010–19: a systematic analysis for the Global Burden of Disease Study 2019
BACKGROUND: Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. METHODS: The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk–outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. FINDINGS: Globally, in 2019, the risk factors included in this analysis accounted for 4·45 million (95% uncertainty interval 4·01–4·94) deaths and 105 million (95·0–116) DALYs for both sexes combined, representing 44·4% (41·3–48·4) of all cancer deaths and 42·0% (39·1–45·6) of all DALYs. There were 2·88 million (2·60–3·18) risk-attributable cancer deaths in males (50·6% [47·8–54·1] of all male cancer deaths) and 1·58 million (1·36–1·84) risk-attributable cancer deaths in females (36·3% [32·5–41·3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20·4% (12·6–28·4) and DALYs by 16·8% (8·8–25·0), with the greatest percentage increase in metabolic risks (34·7% [27·9–42·8] and 33·3% [25·8–42·0]). INTERPRETATION: The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden
Case series of Fanconi anemia in Hevi pediatric hospital-Duhok
Background and objective: Fanconi anemia is a rare inherited autosomal recessive disease characterized by chromosomal instability, progressive bone marrow failure, congenital malformations, and a high propensity of malignancies. Fanconi anemia is a genetically and phenotypically heterogeneous disorder defined by cellular hypersensitivity to DNA cross-linking agents. This study aimed to review retrospectively medical history, genetics, clinical course, blood test results, complications and social issues of Fanconi anemia patients.
Methods: All the patients with Fanconi anemia included in the study had been diagnosed between August 2008 and August 2016 in the Hevi pediatric teaching hospital, Duhok, Kurdistan-Iraq. The cases identified initially, which fulfilled clinical, peripheral blood and bone marrow examination (aspirate and biopsy) and confirmed by the cytogenic study as criteria of inherited hypoplastic anemia. Other causes of aplastic marrow were excluded.
Results: The study includes 30 Fanconi anemia cases,the median age at diagnosis was 7.5 years (range 1.5-15); At diagnosis the most blood parameters were reduced hemoglobin (63%), reduced platelets (57%) followed reduced leukocytes (53%) and 9 (30%) cases, all three peripheral blood count elements were reduced. Moderate aplastic anemiawas predominant, and common symptom (20 cases, 66.7%) washemorrhagic diathesis at presentation.Common physical abnormalities were skin pigmentation (70%), short stature (66.7%), thumb deformity (56.7%),and (53.3%) of the patients had small faces and eyes. Up to 33.3% of all Fanconi anemia patients exhibit none of the physical findings.
Conclusion: Fanconi anemia is a rare genetic disease in Duhok area;most patients were of moderate aplastic anemia, the bleeding tendency was the chief complaint of presentation.The diagnosis of Fanconi anemia in the early stage is important to select special management