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1.
Sensors (Basel) ; 24(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38339534

RESUMO

A vehicular ad hoc network (VANET) is a sophisticated wireless communication infrastructure incorporating centralized and decentralized control mechanisms, orchestrating seamless data exchange among vehicles. This intricate communication system relies on the advanced capabilities of 5G connectivity, employing specialized topological arrangements to enhance data packet transmission. These vehicles communicate amongst themselves and establish connections with roadside units (RSUs). In the dynamic landscape of vehicular communication, disruptions, especially in scenarios involving high-speed vehicles, pose challenges. A notable concern is the emergence of black hole attacks, where a vehicle acts maliciously, obstructing the forwarding of data packets to subsequent vehicles, thereby compromising the secure dissemination of content within the VANET. We present an intelligent cluster-based routing protocol to mitigate these challenges in VANET routing. The system operates through two pivotal phases: first, utilizing an artificial neural network (ANN) model to detect malicious nodes, and second, establishing clusters via enhanced clustering algorithms with appointed cluster heads (CH) for each cluster. Subsequently, an optimal path for data transmission is predicted, aiming to minimize packet transmission delays. Our approach integrates a modified ad hoc on-demand distance vector (AODV) protocol for on-demand route discovery and optimal path selection, enhancing request and reply (RREQ and RREP) protocols. Evaluation of routing performance involves the BHT dataset, leveraging the ANN classifier to compute accuracy, precision, recall, F1 score, and loss. The NS-2.33 simulator facilitates the assessment of end-to-end delay, network throughput, and hop count during the path prediction phase. Remarkably, our methodology achieves 98.97% accuracy in detecting black hole attacks through the ANN classification model, outperforming existing techniques across various network routing parameters.

2.
Soc Sci Med ; 315: 115520, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36413856

RESUMO

Workers exposed to gender harassment and illegitimate tasks may experience adverse mental health outcomes such as depression and burnout. However, the longitudinal effects and the complex interrelationships between these variables remain largely unexplored. We investigated the cross-lagged relationships between gender harassment, illegitimate tasks, and mental health outcomes among working adults in Sweden over a period of two years, as well as the gender differences in the cross-lagged effects. Additionally, the study examined whether illegitimate tasks mediated the relationship between gender harassment and negative mental health outcomes over time. Data were drawn from the Swedish Longitudinal Occupational Survey of Health (SLOSH), covering 2796 working men and 4110 working women in a two-wave analysis from 2018 to 2020. We employed a structural equation model to examine the cross-lagged effects and the mediating effect between gender harassment, illegitimate tasks, and mental health outcomes over time. Furthermore, we applied a multigroup analysis to determine gender differences in the cross-lagged effects. The results showed statistically significant cross-lagged relationships (forward, reverse, and reciprocal) between gender harassment, illegitimate tasks, and mental ill-health. There were statistically significant gender differences in these cross-lagged relationships (burnout: △χ2(47)=106.21, p < 0.01; depression: △χ2(47)=80.5, p < 0.01). Initial illegitimate tasks mediated the relationship between gender harassment and mental ill-health outcomes over time. The gender differences in the interrelationships between gender harassment, illegitimate tasks, and mental ill-health outcomes among workers in Sweden indicate that policies, regulations, and interventions that address these exposures in organisations must be tailored to benefit both men and women.


Assuntos
Saúde Mental , Mulheres Trabalhadoras , Adulto , Masculino , Feminino , Humanos , Local de Trabalho , Suécia/epidemiologia , Estudos de Coortes
3.
Saudi J Biol Sci ; 29(4): 3033-3039, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35531144

RESUMO

Peanut, the only cash crop of rainfed areas of Pakistan, is facing immense challenges due to global warming. Climatic factors particularly the temperature fluctuations and rain pattern shift significantly impact the production and yield of peanut and unavailability of resilient varieties exacerbate this impact. To deal with the cropping pattern change and yield losses, due to climate vagaries, a study was conducted to develop early maturing hybrids using line into tester mating design. The F1 hybrids from the parental lines were produced in the year 2018 using Line × Tester mating design and then grown in the field in the year 2019 for further evaluation. The hybrids were evaluated based on the early maturity and yield-related attributes in comparison with the parental lines. Based on the general combining ability estimate, line V-3 (Golden), was found as best parent with highly significant values for plant height, days to peg formation, days to maturity, number of pegs per plant, number of pods per plants, number of seeds per plant, 100 pod weight 100 seed weight. Similarly, tester V-7 (PI 635006 01 SD) showed highly significant results of GCA for days to germination, day to 50% flowering, plant height, days to peg formation, days to maturity, number of pegs per plant, number of pods per plants, number of seeds per plant, 100 kernel weight, shelling percentage. All the combinations were evaluated for specific combining ability and significant results were observed for V-3 × V-4 (Golden × PI 619175 01 SD) and V-1 × V-6 (BARI-2000 × PI 564846 01 SD) by developing or maturity and yield-related attributes. The hybrid combinations V-3 × V-5 (Golden × PI 635006 01 SD) followed by V-3 × V-6 showed highly significant results for mid parent heterosis and better parent heterosis for days to 50% flowering, plant height, days to peg formation, number of pegs, days to maturity, number of mature seeds per plant, shelling ratio, 100 pod weight and 100 kernel weight. These parents and hybrid combinations with early maturity genes and high yield attributes can further be used for the development of short duration variety.

4.
Int J Plant Prod ; 16(3): 341-363, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35614974

RESUMO

Dryland agricultural system is under threat due to climate extremes and unsustainable management. Understanding of climate change impact is important to design adaptation options for dry land agricultural systems. Thus, the present review was conducted with the objectives to identify gaps and suggest technology-based intervention that can support dry land farming under changing climate. Careful management of the available agricultural resources in the region is a current need, as it will play crucial role in the coming decades to ensure food security, reduce poverty, hunger, and malnutrition. Technology based regional collaborative interventions among Universities, Institutions, Growers, Companies etc. for water conservation, supplemental irrigation, foliar sprays, integrated nutrient management, resilient crops-based cropping systems, artificial intelligence, and precision agriculture (modeling and remote sensing) are needed to support agriculture of the region. Different process-based models have been used in different regions around the world to quantify the impacts of climate change at field, regional, and national scales to design management options for dryland cropping systems. Modeling include water and nutrient management, ideotype designing, modification in tillage practices, application of cover crops, insect, and disease management. However, diversification in the mixed and integrated crop and livestock farming system is needed to have profitable, sustainable business. The main focus in this work is to recommend different agro-adaptation measures to be part of policies for sustainable agricultural production systems in future.

5.
Saudi J Biol Sci ; 29(6): 103300, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35540177

RESUMO

Common bean (Phaseolus vulgaris L.) is a legume crop grown all over the world and is a very important food of mountain population of Pakistan for protein intake. The Western Himalayan Mountains are rich in biodiversity including unexplored landraces of the common bean crop. Unfortunately, very little attention has been given to this valuable crop in Pakistan, and it is being exported, majorly from Ethiopia, to meet the country's requirements. The exploitation, utilization, preservation and multiplication of existing germplasm within the area are very important for sustainable production of the crop and enhancing the nutrition value for the local community in mountain regions. A research study was conducted for evaluation of biological diversity of common bean landraces from Azad Kashmir and Northern areas of Pakistan using morpho-physiological and molecular markers. Thirty-five common bean ecotypes along with one check variety were collected from different altitudes of Azad Kashmir and Northern Pakistan and screened for biological diversity. Morphological characterization revealed high genetic diversity in parameters including stem anthocyanin, growth type, days to flowering, pods/plant and 100 seeds weight. Genomic characterization using SSR markers, for allelic diversity evaluation among germplasm, also provided diverse profile with 83.3% polymorphism in banding pattern. The bulk of gene pool diversity evaluated within bean landraces may help to initiate breeding program for common bean improvement.

6.
PLoS One ; 16(5): e0250790, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33974643

RESUMO

In recent years, the trigonometric families of continuous distributions have found a place of choice in the theory and practice of statistics, with the Sin-G family as leader. In this paper, we provide some contributions to the subject by introducing a flexible extension of the Sin-G family, called the transformed Sin-G family. It is constructed from a new polynomial-trigonometric function presenting a desirable "versatile concave/convex" property, among others. The modelling possibilities of the former Sin-G family are thus multiplied. This potential is also highlighted by a complete theoretical work, showing stochastic ordering results, studying the analytical properties of the main functions, deriving several kinds of moments, and discussing the reliability parameter as well. Then, the applied side of the proposed family is investigated, with numerical results and applications on the related models. In particular, the estimation of the unknown model parameters is performed through the use of the maximum likelihood method. Then, two real life data sets are analyzed by a new extended Weibull model derived to the considered trigonometric mechanism. We show that it performs the best among seven comparable models, illustrating the importance of the findings.


Assuntos
Estatística como Assunto , Modelos Estatísticos
7.
J Exp Bot ; 72(10): 3846-3863, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33765129

RESUMO

Phosphorus and nitrogen nutrition have profound and complicated innate connections; however, underlying molecular mechanisms are mostly elusive. PHR1 is a master phosphate signaling component, and whether it directly functions in phosphorus-nitrogen crosstalk remains a particularly interesting question. In maize, nitrogen limitation caused tip kernel abortion and ear shortening. By contrast, moderately low phosphate in the field reduced kernels across the ear, maintained ear elongation and significantly lowered concentrations of total free amino acids and soluble proteins 2 weeks after silking. Transcriptome profiling revealed significant enrichment and overall down-regulation of transport genes in ears under low phosphate. Importantly, 313 out of 847 differentially expressed genes harbored PHR1 binding sequences (P1BS) including those controlling amino acid/polyamine transport and metabolism. Specifically, both ZmAAP2 and ZmLHT1 are plasma membrane-localized broad-spectrum amino acid transporters, and ZmPHR1.1 and ZmPHR1.2 were able to bind to P1BS-containing ZmAAP2 and ZmLHT1 and down-regulate their expression in planta. Taken together, the results suggest that prevalence of P1BS elements enables ZmPHR1s to regulate a large number of low phosphate responsive genes. Further, consistent with reduced accumulation of free amino acids, ZmPHR1s down-regulate ZmAAP2 and ZmLHT1 expression as direct linkers of phosphorus and nitrogen nutrition independent of NIGT1 in maize ear under low phosphate.


Assuntos
Fatores de Transcrição , Zea mays , Sistemas de Transporte de Aminoácidos , Regulação da Expressão Gênica de Plantas , Fosfatos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zea mays/genética , Zea mays/metabolismo
8.
Plants (Basel) ; 9(11)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33203052

RESUMO

Salinity and drought stress, singly or in combination, are major environmental menaces. Jatropha curcas L. is a biodiesel plant that can tolerate long periods of drought. However, the growth performance and stress tolerance based on physical, chemical, and physiological attributes of this plant have not yet been studied. To address this question, J. curcas seedlings were grown in a completely randomized design in plastic pots filled with soil to evaluate the effects of salinity and drought stresses on growth, ionic composition, and physiological attributes. The experiment consisted of six treatments: control (without salinity and drought stress), salinity alone (7.5 dS m-1, 15 dS m-1), drought, and a combination of salinity and drought (7.5 dS m-1+ Drought, 15 dS m-1+Drought). Our results revealed that, compared with the control, both plant height (PH) and stem diameter (SD) were reduced by (83%, 80%, and 77%) and (69%, 56%, and 55%) under salinity and drought combination (15 dS m-1+Drought) after three, six, and nine months, respectively. There was 93% more leaf Na+ found in plants treated with 15 dS m-1+Drought compared with the control. The highest significant average membrane stability index (MSI) and relative water content (RWC) values (81% and 85%, respectively) were found in the control. The MSI and RWC were not influenced by 7.5 dS m-1 and drought treatments and mostly contributed towards stress tolerance. Our findings imply that J. curcas is moderately tolerant to salinity and drought. The Na+ toxicity and disturbance in K+: Na+ ratio were the main contributing factors for limited growth and physiological attributes in this plant.

9.
Front Plant Sci ; 11: 187, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32184798

RESUMO

Amongst various environmental constraints, abiotic stresses are increasing the risk of food insecurity worldwide by limiting crop production and disturbing the geographical distribution of food crops. Millets are known to possess unique features of resilience to adverse environments, especially infertile soil conditions, although the underlying mechanisms are yet to be determined. The small diploid genome, short stature, excellent seed production, C4 photosynthesis, and short life cycle of foxtail millet make it a very promising model crop for studying nutrient stress responses. Known to be a drought-tolerant crop, it responds to low nitrogen and low phosphate by respective reduction and enhancement of its root system. This special response is quite different from that shown by maize and some other cereals. In contrast to having a smaller root system under low nitrogen, foxtail millet enhances biomass accumulation, facilitating root thickening, presumably for nutrient translocation. The low phosphate response of foxtail millet links to the internal nitrogen status, which tends to act as a signal regulating the expression of nitrogen transporters and hence indicates its inherent connection with nitrogen nutrition. Altogether, the low nitrogen and low phosphate responses of foxtail millet can act as a basis to further determine the underlying molecular mechanisms. Here, we will highlight the abiotic stress responses of foxtail millet with a key note on its low nitrogen and low phosphate adaptive responses in comparison to other crops.

10.
Psychometrika ; 84(4): 1101-1128, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31183669

RESUMO

Item calibration is a technique to estimate characteristics of questions (called items) for achievement tests. In computerized tests, item calibration is an important tool for maintaining, updating and developing new items for an item bank. To efficiently sample examinees with specific ability levels for this calibration, we use optimal design theory assuming that the probability to answer correctly follows an item response model. Locally optimal unrestricted designs have usually a few design points for ability. In practice, it is hard to sample examinees from a population with these specific ability levels due to unavailability or limited availability of examinees. To counter this problem, we use the concept of optimal restricted designs and show that this concept naturally fits to item calibration. We prove an equivalence theorem needed to verify optimality of a design. Locally optimal restricted designs provide intervals of ability levels for optimal calibration of an item. When assuming a two-parameter logistic model, several scenarios with D-optimal restricted designs are presented for calibration of a single item and simultaneous calibration of several items. These scenarios show that the naive way to sample examinees around unrestricted design points is not optimal.


Assuntos
Calibragem/normas , Computadores , Avaliação Educacional/normas , Modelos Estatísticos , Psicometria , Algoritmos , Humanos
11.
J Immunol ; 193(5): 2273-86, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25080482

RESUMO

Fish type I IFNs are classified into two groups with two (group I) or four (group II) cysteines in the mature peptide and can be further divided into four subgroups, termed IFN-a, -b, -c, and -d. Salmonids possess all four subgroups, whereas other teleost species have one or more but not all groups. In this study, we have discovered two further subgroups (IFN-e and -f) in rainbow trout Oncorhynchus mykiss and analyzed the expression of all six subgroups in rainbow trout and brown trout Salmo trutta. In rainbow trout RTG-2 and RTS-11 cells, polyinosinic-polycytidylic acid stimulation resulted in early activation of IFN-d, whereas the IFN-e subgroup containing the highest number of members showed weak induction. In contrast with the cell lines, remarkable induction of IFN-a, -b, and -c was detected in primary head kidney leukocytes after polyinosinic-polycytidylic acid treatment, whereas a moderate increase of IFNs was observed after stimulation with resiquimod. Infection of brown trout with hemorrhagic septicemia virus resulted in early induction of IFN-d, -e, and -f and a marked increase of IFN-b and IFN-c expression in kidney and spleen. IFN transcripts were found to be strongly correlated with the viral burden and with marker genes of the IFN antiviral cascade. The results demonstrate that the IFN system of salmonids is far more complex than previously realized, and in-depth research is required to fully understand its regulation and function.


Assuntos
Proteínas de Peixes/genética , Loci Gênicos/fisiologia , Interferon Tipo I/genética , Oncorhynchus mykiss/genética , Animais , Sequência de Bases , Proteínas de Peixes/imunologia , Interferon Tipo I/imunologia , Dados de Sequência Molecular , Oncorhynchus mykiss/imunologia , Especificidade de Órgãos/fisiologia
12.
J Ayub Med Coll Abbottabad ; 21(3): 95-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20929024

RESUMO

OBJECTIVE: To determine the immediate and intermediate term outcome of balloon pulmonic valvuloplasty by echocardiography. METHODS: This study was conducted in the Department of Cardiology Postgraduate Medical Institute Lady Reading Hospital (LRH), Peshawar from July 1999 to January 2003. Patients with severe pulmonic valve stenosis who underwent balloon pulmonic valvuloplasty during this period were included in the study. Forty Patients fulfilling the study inclusion criteria were followed up to 18 months by two dimensional and Doppler echocardiographic examinations at 6 months interval. Patients with dysplastic valve leaflets or for whom 18 months follow up data was not available were excluded from the study. Echocardiographic data was collected prospectively. Echocardiographic hemodynamic data was analysed initially and at all three follow up visits, using descriptive statistics and paired t-test. RESULTS: Total 64 balloon pulmonic valvuloplasty procedures were performed during this period. Forty patients fulfilled the study inclusion criteria and the remaining 24 patients were excluded from the study. Mean age of the patients was 13.05 +/- 8.22 years, ranging from 1-33 years. Pre-peak pulmonic valve gradient reduced from 100.9 +/- 29.20 mmHg to 31.38 +/- 15.99 mmHg (p < 0.0001) immediately after balloon pulmonic valvuloplasty. Pulmonic valve gradient at day 1 (31.38 +/- 15.99) reduced significantly at 18 months (18.88 +/- 10.24) (p < 0.0001). Complication encountered during the procedure was transient ventricular tachycardia or multiple premature ventricular contractions. CONCLUSION: Balloon pulmonic valvuloplasty is safe and effective in reducing pulmonic valve gradient acutely and the benefit persists till 18 months. Further fall in pulmonic valve gradient is seen in intermediate term follow up.


Assuntos
Cateterismo/métodos , Estenose da Valva Pulmonar/terapia , Adolescente , Adulto , Criança , Pré-Escolar , Ecocardiografia , Feminino , Seguimentos , Hemodinâmica , Humanos , Lactente , Masculino , Estudos Prospectivos , Estenose da Valva Pulmonar/diagnóstico por imagem , Estenose da Valva Pulmonar/fisiopatologia , Resultado do Tratamento
13.
J Ayub Med Coll Abbottabad ; 21(3): 155-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20929037

RESUMO

BACKGROUND: Prevention of sudden cardiac death has always been a challenge for electrophysiologists and to date, automatic implantable cardiovertor defibrillator (AICD) is found to be the only remedy. This device delivers an intracardiac shock whenever it senses a fatal ventricular arrhythmia in order to achieve sinus rhythm. If the delivery of these intracardiac shocks becomes frequent, the situation is declared as an electrical storm. This article deals with the frequency, precipitating factors and prevention of electrical storms. METHODS: One hundred and ten episodes of electrical storms (a total of 668 shocks) were retrospectively analysed in 25 recipients of automatic implantable cardioverter defibrillators. ECG, echocardiography, serum electrolytes, urea and creatinine were done for all the patients, and they were hospitalized for a minimum of 24 hours. RESULTS: During the 3 year study period, all the 25 patients with an implantable cardiovertor defibrillator, on an average, received one shock per two years. However, 12 out of these 25 patients (50%) had more than two shocks within 24 hours. Most of these patients with electrical storms were having active ischemia, electrolytes imbalances or renal failure. CONCLUSION: Electrical storms are common in patients with coronary artery disease with impaired left ventricular functions. Ischemia, electrolytes imbalances and renal failure predispose to the electrical storms. Electrical Storms are predictors of poor prognosis.


Assuntos
Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Taquicardia Ventricular/fisiopatologia , Fibrilação Ventricular/fisiopatologia , Ecocardiografia , Eletrocardiografia , Eletrólitos/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taquicardia Ventricular/terapia , Fibrilação Ventricular/terapia
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