75 research outputs found
Performance of vapour pressure models in the computation of vapour pressure and evapotranspiration in ABHA, ASIR region, Saudi Arabia
The FAO-56 Penman-Monteith model is recognized as the standard method for estimating reference evapotranspiration (ETo) which requires daily meteorological data as inputs. Among all input data, vapour pressure deficit (VPD) is one of the critical parameter that drives evapotranspiration (ETo), and is of fundamental importance in crop models. In this study effort has been made to compare six vapour pressure models during four seasons. Three vapour pressure models (Models 1–3) selected as mentioned in Irrigation and Drainage Paper-56 of the Food and Agriculture Organization (FAO-56) and Models 4-6 has been selected from literature survey. Model 1, which uses daily maximum and minimum temperature, relative humidity (RH), is the preferred method to estimate actual air pressure (AE) hence it is used as standard for comparing other models. The effectiveness of vapour pressure models were measured by statistical tools and ranked according to Global Performance Indicator (GPI) where higher value of GPI represent best model. The ranking order using GPI shows that Model 5 resulted in best estimation capability with a GPI of 2.77. Moreover, the effect of variation in wind speed on the performance of the vapour pressure models in ETo estimation is also assessed
Calibration and validation of reference evapotranspiration models in semi-arid conditions
Reference evapotranspiration (ETo) is an important parameter for climatological, hydrological and agricultural management. The FAO56 Penman-Monteith (FAO56-PM) model is one of the most accurate models. But it needs a detailed climate dataset from weather stations. Therefore, empirical reference evapotranspiration models (ETo) that need a reduced set of climate data can become an alternative approach. In this study, nine different evapotranspiration models were calibrated for the 1978-2000 period and validated based on the period between 2001-2017 with respect to standard FAO56-PM method based on the real climatic data obtained from Aseer metrological department, Saudi Arabia. The ranking of all the evaluated models based on the multi-criteria decision making was done in order to get the best alternative to the FAO56-PM Model. The result showed that Mahringer and Trabert models are the most appropriate with RMSE values of 2.13 mm/day and 2.47 mm/day, respectively and the value of percent error were 77.27% and 89.43%, respectively. Moreover, the values of mean bias error were found to be-2.03 mm/day and-2.35 mm/day, respectively. The calibration and validation of different ETo equations tend to increase their performance. Thus, the validated evapotranspiration model that used less climatic parameters could predict the ETo condition accurately for any region
Clinical use of vorapaxar as an emerging antithrombin agent: A literature review of current evidence
In response to the high prevalence of atherothrombotic diseases and the residual risks left by the current antiplatelet therapies, the Food and Drug Administration approved the use of vorapaxar as a secondary prevention of cardiovascular events. Vorapaxar is a novel oral antiplatelet agent that antagonizes protease-activated receptor-1 and inhibits platelet activation without influencing coagulation parameters. In this review, we summarized findings of the main studies and the subanalyses from two pivotal phase III clinical trials of vorapaxar, as well as the results of the available observational studies to assist treatment decision-making of vorapaxar for clinicians. Evidence shows that vorapaxar treatment brings favorable results to patients with myocardial infraction history, peripheral arterial diseases, and acute coronary syndrome and those who underwent coronary artery bypass grafting surgery. Studies supported the efficacy of vorapaxar in treating incident coronary stent thrombosis, acute limb ischemia, and peripheral revascularization which outweighed the safety concern of bleeding. However, vorapaxar should not be administered to patients with prior stroke or transient ischemic attack due to excessive risks of bleeding. Future studies should focus on examining the long-term risks and benefits of vorapaxar on single cardiovascular outcomes and the optimal dosage of vorapaxar for different patient populations
The Dynamics of Interpretive Communities and the Contemporary Saudi Novel: A Study in the Reception of Abdo Khal, Raja Alem, Rajaa Alsanea and Yousef al-Mohaimeed
The research undertaken in this thesis focuses on the reception by different groups of readers in both the Arab and Western worlds of four novels written by Saudi authors: Abdo Khal’s Tarmī bi-sharar… (Throwing Sparks), Raja Alem’s Ṭawq al-Ḥamām (The Dove’s Necklace), Rajaa Alsanea’s Banāt al-riyāḍ (Girls of Riyadh) and Yousef al-Mohaimeed’s Fikhākh al-Rā’iḥa (Wolves of the Crescent Moon). In order to analyse this critical discourse, this study draws on Fish’s (1980) concept of ‘interpretive communities’, combining this with a detailed examination of the socio-cultural and ideological contexts that shaped the reception of these works.
This thesis is divided into eight chapters. Chapter one elaborates the research background, the aims of the study, its significance and the research questions that both motivate and structure this thesis. Chapter Two provides a detailed account of available research and theories related to the Saudi novel and the reception theory as well as the data used and the methodology applied. Chapter Three discusses the political, social and cultural contexts that have shaped the Saudi literary space, detailing how these are reflected in the Saudi novel and the extent to which they have affected its development. Chapter Four highlights the important factors that have significantly affected the status and reception of the contemporary Saudi novel.
Chapters five and six examine the reception of these four contemporary Saudi novels by different groups of Arab readers, focusing on two main groups of readers and readings: Arab journalists, both Saudi and non-Saudi (simplistic readings); and Arab literary critics, both Saudi and non-Saudi (professional readings).
Chapter seven explores how these four Saudi novels have attracted the attention of Anglophone journalists and academics following their translation into English. It argues that the cultural experiences of Anglophone readers differ from those of the original target audience, which influences the act of textual interpretation
Tumefactive demyelinating lesions in a patient with multiple sclerosis receiving natalizumab
Letter to the Editor: Critical illness polyneuropathy/critical illness myopathy and acute motor-sensory axonal neuropathy
Preparation and Characterization of Curcumin Nanoemulgel Utilizing Ultrasonication Technique for Wound Healing: In Vitro, Ex Vivo, and In Vivo Evaluation
Hydrogels being a drug delivery system has great significance particularly for topical application in cutaneous open wound. Its specific physicochemical properties such as non-adhesiveness, moisture retention, exudate absorption, and gas permeability make them ideal as a drug delivery vehicle for wound healing application. Further, curcumin (a natural bioactive) was selected as a therapeutic agent to incorporate into the hydrogel system to design and develop nanogel pharmaceutical products for wound healing. Although, curcumin possesses remarkable anti-inflammatory, antioxidant, and anti-infective activity along with hastening the healing process by acting over the different stages of the wound healing process, but its poor biopharmaceutical (low aqueous solubility and skin penetrability) attributes hamper their therapeutic efficacy for skin applications. The current investigation aimed to develop the curcumin-loaded nanogel system and evaluated to check the improvement in the therapeutic efficacy of curcumin through a nanomedicine-based approach for wound healing activity in Wistar rats. The curcumin was enclosed inside the nanoemulsion system prepared through a high-energy ultrasonic emulsification technique at a minimum concentration of surfactant required to nanoemulsify the curcumin-loaded oil system (Labrafac PG) having droplet size 56.25 ± 0.69 nm with polydispersity index 0.05 ± 0.01 and negatively surface charge with zeta potential −20.26 ± 0.65 mV. It was observed that the impact of Smix (surfactant/co-surfactant mixture) ratio on droplet size of generated nanoemulsion is more pronounced at lower Smix concentration (25%) compared to the higher Smix concentration (30%). The optimized curcumin-loaded nanoemulsion was incorporated into a 0.5% Carbopol® 940 hydrogel system for topical application. The developed curcumin nanoemulgel exhibited thixotropic rheological behavior and a significant (p < 0.05) increase in skin penetrability characteristics compared to curcumin dispersed in conventional hydrogel system. The in vivo wound healing efficacy study and histological examination of healed tissue specimen further signify the role of the nanomedicine-based approach to improve the biopharmaceutical attributes of curcumin
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