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1.
PLoS One ; 19(6): e0302135, 2024.
Article in English | MEDLINE | ID: mdl-38861530

ABSTRACT

Soilless agriculture is acknowledged worldwide because it uses organic leftovers as a means of supporting intensive and efficient plant production. However, the quality of potting media deteriorates because of lower nutrient content and excessive shrinkage of most organic materials. A current study was undertaken to identify the optimal blend of locally available organic materials with desirable qualities for use as potting media. Therefore, different ingredients, viz., Pinus roxburghii needles, sugarcane bagasse, and farmyard manure were used alone or in combination as potting media to test their suitability by growing spinach as a test crop. Results showed that an increase in Pinus roxburghii needles and sugarcane bagasse decreased medium pH and electrical conductivity. Higher pH and electrical conductivity were recorded for the treatments having a higher farmyard manure ratio (≥50%) in combination. Except for pine needles 100%, pH and electrical conductivity were in the recommended range. The growth attributes include, leaves plant-1, shoot length, fresh- and dry shoot weight along with plant macronutrients (nitrogen, phosphorous, and potassium) and micronutrients (iron, copper, manganese, and zinc) content were higher in treatment pine needles 50%+farmyard manure 50% followed by pine needles 25%+farmyard manure 50%+sugarcane bagasse 25%. Moreover, the particular treatment of pine needles 50%+farmyard manure 50% exhibited the highest concentrations of macro- (nitrogen, phosphorus, and potassium) as well as micronutrients (iron, copper, manganese, and zinc) in the potting media following the harvest. This study highlights the potential of utilizing agro-industrial litter/waste as a soilless growing medium for spinach production under greenhouse conditions. When employed in appropriate proportions, this approach not only addresses disposal concerns but also proves effective for sustainable cultivation. Further research is needed to investigate the use of these wastes as potting media by mixing various particle-size ingredients.


Subject(s)
Manure , Pinus , Saccharum , Manure/analysis , Saccharum/growth & development , Saccharum/chemistry , Pinus/growth & development , Cellulose , Vegetables/growth & development , Vegetables/chemistry , Spinacia oleracea/growth & development , Spinacia oleracea/metabolism , Hydrogen-Ion Concentration , Electric Conductivity , Agriculture/methods , Plant Leaves/growth & development , Plant Leaves/chemistry , Soil/chemistry , Nitrogen/analysis
2.
Sci Total Environ ; 928: 172265, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38621534

ABSTRACT

Extensive unforested sandy areas on the margins of floodplains and riverbeds, formed by dunes, barchans, and accumulation berms, are a ubiquitous feature across northern Eurasia and Alaska. These dynamic landscapes, which bear witness to the complex Holocene and modern climatic fluctuations, provide a unique opportunity to study ecosystem evolution. Within this heterogeneous assemblage, active dunes, characterized by their very sparse plant communities, contrast sharply with the surrounding taiga (boreal) forests common for the stabilized dunes. This juxtaposition makes these regions to natural laboratories to study vegetation succession and soil development. Through a comprehensive analysis of climate, geomorphology, vegetation, soil properties, and microbiome composition, we elucidate the intricacies of cyclic and linear ecosystem evolution within a representative sandy area located along the lower Nadym River in Siberia, approximately 100 km south of the Arctic Circle. The shift in the Holocene wind regime and the slow development of vegetation under harsh climatic conditions promoted cyclical ecosystem dynamics that precluded the attainment of a steady state. This cyclical trajectory is exemplified by Arenosols, characterized by extremely sparse vegetation and undifferentiated horizons. Conversely, accelerated vegetation growth within wind-protected enclaves on marginally stabilized soils facilitated sand stabilization and subsequent pedogenesis towards Podzols. Based on soil acidification due to litter input (mainly needles, lichens, and mosses) and the succession of microbial communities, we investigated constraints on carbon and nutrient availability during the initial stages of pedogenesis. In summary, the comprehensive study of initial ecosystem development on sand dunes within taiga forests has facilitated the elucidation of both common phases and spatiotemporal dynamics of vegetation and soil succession. This analysis has further clarified the existence of both cyclic and linear trajectories within the successional processes of ecosystem evolution.


Subject(s)
Ecosystem , Soil , Taiga , Siberia , Soil/chemistry , Sand , Environmental Monitoring , Microbiota , Soil Microbiology
3.
Angiology ; 75(4): 331-339, 2024 Apr.
Article in English | MEDLINE | ID: mdl-36710003

ABSTRACT

There is no consensus regarding mitral valve management during surgical ventricular restoration (SVR) for ischemic cardiomyopathy. We compared the impact of SVR with mitral valve repair (MVr) vs replacement (MVR) on postoperative outcomes and long-term survival in ischemic cardiomyopathy and mitral regurgitation patients. This study included 112 patients who underwent SVR from 2009 to 2018 with MVr (n = 75) or MVR (n = 37). Patients who had MVR had higher Euro SCORE II, dyspnea class, a lower ejection fraction, higher pulmonary artery systolic pressure, higher grade of preoperative mitral and tricuspid regurgitation, and higher end-diastolic and end-systolic diameters. Intra-aortic balloon pump was more commonly used in patients with MVR. Hospital mortality occurred in 7 (9.33%) patients in the MVr group vs 3 (8.11%) in the MVR group (P > .99). Freedom from rehospitalization at 1, 5, and 7 years was 87%, 76%, and 70% in the MVr group and 83%, 61%, and 52% in the MVR group (P = .191). Survival at 1, 5, and 7 years was 88%, 78%, and 74% in the MVr group and 88%, 56%, and 56% in the MVR group (P = .027). Adjusted survival did not differ between groups.MVr or MVR are valid options in patients undergoing SVR, with good long-term outcomes.


Subject(s)
Cardiomyopathies , Heart Valve Prosthesis Implantation , Mitral Valve Insufficiency , Myocardial Ischemia , Humans , Mitral Valve/surgery , Heart Valve Prosthesis Implantation/adverse effects , Treatment Outcome , Myocardial Ischemia/complications , Myocardial Ischemia/surgery , Mitral Valve Insufficiency/surgery , Cardiomyopathies/surgery
4.
Perfusion ; 39(3): 564-570, 2024 Apr.
Article in English | MEDLINE | ID: mdl-36645201

ABSTRACT

BACKGROUND: Limited data evaluated the outcomes of extracorporeal membrane oxygenation (ECMO) in patients with prosthetic valves. This study aimed to compare the outcomes of ECMO support for postcardiotomy cardiogenic shock in patients with mechanical versus bioprosthetic valves. METHODS: This retrospective study included patients with ECMO support for postcardiotomy cardiogenic shock after valve replacement. Patients were grouped into bioprosthetic (n = 49) and mechanical valve (n = 22) groups. RESULTS: There were no differences in ECMO duration, inotropic support, intra-aortic balloon pump (IABP), stroke, duration of ICU, and hospital stay between groups. Postoperative thrombosis occurred in 2 patients with bioprosthetic valves (5.41%) and 2 with mechanical valves (14.29%), p = .30. All patients with thrombosis had central ECMO cannulation, concomitant IABP, and inotropic support during ECMO. All thrombi were related to the mitral valve. Three patients with thrombi had hospital mortality.Survival at 6, 12, and 36 months for bioprosthetic valve patients was 30.88%, 28.55%, and 25.34% and for mechanical valves was 36.36% for all time intervals (Log-rank p = .93). One patient had bioprosthetic aortic valve endocarditis after 1 year. Three patients with bioprosthetic valves had structural valve degeneration after 1, 2, and 5 years. CONCLUSIONS: Outcomes of ECMO in patients with prosthetic valves are comparable between bioprosthetic and mechanical valves. Thrombosis might occur in both valve types and was associated with high mortality. ECMO could affect the long-term durability of the bioprosthetic valves.


Subject(s)
Extracorporeal Membrane Oxygenation , Stroke , Thrombosis , Humans , Shock, Cardiogenic/etiology , Shock, Cardiogenic/surgery , Extracorporeal Membrane Oxygenation/adverse effects , Retrospective Studies , Stroke/etiology , Thrombosis/etiology
5.
Sci Rep ; 13(1): 19064, 2023 Nov 04.
Article in English | MEDLINE | ID: mdl-37925477

ABSTRACT

Date palm stones are regarded as possible alternatives to activated carbon (AC) precursors with high potential for various environmental applications. In this research study, date palm stones derived activated carbon (DPSAC) was used as adsorbent for removing toxic remazol brilliant blue R (RBBR). The synthesis of DPSAC involved a chemical treatment using KOH and NaOH (1:1). Characterization of DPSAC revealed that it exhibited a BET surface area of 715.30 m2/g, Langmuir surface area of 1061.93 m2/g, total pore volume of 0.39 cm3/g, and average pore diameter of 2.15 nm. Adsorption uptake of RBBR increased (from 24.54 to 248.54 mg/g), whereas the removal percentage decreased (from 98.16 to 82.85%) when the initial RBBR concentration increased (from 25 to 300 mg/L). The adsorption process performed best under acidic conditions (pH 3), with an RBBR uptake of 98.33 mg/g. Because of the high R2 values (0.9906 and 0.9779) and low average errors (6.24 and 13.95%), this adsorption process followed the Freundlich isotherm and pseudo-first-order (PFO) models, respectively. The Langmuir adsorption capacity (Qm) was 319.63 mg/g. Thermodynamic parameters were - 11.34 kJ/mol for ∆H° (exothermic in nature), 0.05 kJ/mol K for ∆S° (increasing randomness level at solid-liquid interface), - 27.37 kJ/mol for ∆G° (spontaneous), and 6.84 kJ/mol for Ea (controlled by physisorption).

7.
Toxics ; 11(2)2023 Jan 19.
Article in English | MEDLINE | ID: mdl-36850971

ABSTRACT

Biochar's agricultural and environmental benefits have been widely demonstrated; however, it may cause environmental contamination if it contains large amounts of pollutants such as polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs). Therefore, this study aimed to assess the contents of PAHs and HM in a range of biochars generated from different sources and pyrolysis temperatures. A range of feedstock was converted to biochar, including sewage sludge (SS), olive mill pomace (OP), feather meal (FM), soft offal meal (CSM), chicken manure (CM), and date palm residues (DPR). Each feedstock was then pyrolyzed at three temperatures of 300, 500, or 700 °C, thereby producing a total of 18 types of biochar. These biochar products were analyzed for 16 PAHs and eight metals (Cr, Mn, Fe, Ni, Cu, Zn, Cd, and Pb). Benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo(a)pyrene were significantly greater in the biochar produced at 700 °C than in that produced at 300 °C, especially for CM. The concentrations of dibenz(a,h)anthracene were significantly lower at 700 °C but greater at 500 °C and 300 °C in DPR. Increasing the pyrolysis temperature from 300 to 700 °C significantly increased the concentrations of metals, including Cr in SS and OP; Mn in CM; and Fe, Ni, Cu, and Zn in SS. However, the concentration of Cd was significantly lower in the SS when biochar was produced at 700 °C than at 500 or 300 °C. The type of feedstock used and the pyrolysis temperature are key factors influencing the contents of PAHs and HMs in biochar, both of which need to be considered during the production and use of biochar. Further investigations are recommended to establish the relationships between pyrolysis temperature and types of feedstock and the formation of PAH or the concentrations of metals. Monitoring the concentrations of PAHs and HMs before applying biochar to soil is also recommended.

8.
ACS Omega ; 7(50): 46079-46089, 2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36570315

ABSTRACT

Remazol Brilliant Blue R (RBBR) is a common dye used in the industry, and its presence in wastewater and discharge into the environment can create a serious concern for the ecosystem and human health. Activated carbon produced from crop residues has emerged as a promising technique for removing contaminants from wastewater. In this study, leaf sheath date palm fiber-based activated carbon (LSDAC) was synthesized via phosphoric acid, H3PO4, treatment, followed by a microwave-induced carbonization process. The produced LSDAC was found to have a BET surface area of 604.61 m2/g, a Langmuir surface area of 922.05 m2/g, a total pore volume of 0.35 cm3/g, and an average pore size of 2.75 nm. The highest removal of RBBR was achieved at a solution pH of 3 (92.56 mg/g) and a solution temperature of 50 °C (90.37 mg/g). Adsorption of RBBR onto LSDAC followed the Langmuir isotherm model with a maximum monolayer capacity, Q m, of 243.43 mg/g, whereas in terms of kinetics, this adsorption system was best described by the pseudo-first-order (PFO) model. The calculated thermodynamic parameters ΔH°, ΔS°, ΔG°, and Arrhenius activation energy, E a, were 4.71 kJ/mol, 0.10 kJ/mol·K, -26.25 kJ/mol, and 5.88 kJ/mol, respectively, indicating that the adsorption of RBBR onto LSDAC was endothermic in nature, exhibited increased randomness at the solid-liquid interface, and was spontaneous and controlled by physisorption.

9.
J Card Surg ; 37(12): 5591-5594, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36378911

ABSTRACT

Management of patients with end-stage heart failure is still challenging. We report a case of idiopathic dilated cardiomyopathy who went through a challenging course. The case was presented as acute heart failure syndrome, which rapidly declined into cardiogenic shock and cardiac arrest that required an extracorporeal membrane oxygenator, then biventricular assist device implantation for circulatory support. The course was complicated with severe gastrointestinal bleeding and multiorgan failure until achieving full cardiac and organ recovery. The left ventricle ejection fraction improved from 10% to 50% at discharge.


Subject(s)
Cardiomyopathy, Dilated , Heart Failure , Heart-Assist Devices , Humans , Cardiomyopathy, Dilated/complications , Cardiomyopathy, Dilated/therapy , Shock, Cardiogenic/etiology , Shock, Cardiogenic/therapy , Heart Failure/therapy , Heart Failure/complications , Heart-Assist Devices/adverse effects , Myocardium , Treatment Outcome
10.
Saudi J Biol Sci ; 28(12): 7491-7498, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34867054

ABSTRACT

Organic residues are an important factor that directly affects fruiting tree seedlings' health at earlier stages. It provides a suitable environment for seedling growth by providing better nutrient ions, water, and aeration. However, low organic contents and high shrinkage of most organic materials mostly deteriorate ideal potting media characteristics. Low aeration, high water, and nutrients leaching decrease seedling growth and cause a significant loss of valuable resources. That is why the current study was conducted to screen out the best indigenous materials based on particle size to produce good characteristics bearing potting media. For that, eight different ingredients, i.e., "sugarcane", "coconut coir", "wheat straw", "rice straw", "corn cob", "leaf litter", "farmyard manure", and "sunflower heads" were collected. Initially, all the materials were air-dried and processes as per requirement. After grinding, three particles size (fine = < 2 mm, medium = 3 mm and coarse = 5 mm) were separated by sieving. Results showed that decreasing particle size in "rice straw", "corn cob", "farmyard manure," and "sunflower head" decreased leachate pH. Higher EC in leachates was negatively correlated with particle size in all potting media ingredients. Except for farmyard manure, fine particle size increases the water-holding ability of potting media ingredients. However, air-filled porosity was associated with a decrease in particle size of potting media in gradients. In conclusion, farmyard manure, "sunflower heads", "leaf litter" and "sugarcane" should be incorporated while making a combination for potting media. More investigations are suggested by mixing different particle size ingredients to prepare potting media.

11.
Saudi J Kidney Dis Transpl ; 32(1): 69-83, 2021.
Article in English | MEDLINE | ID: mdl-34145116

ABSTRACT

Very few detailed descriptive studies focusing on peritonitis in patients on peritoneal dialysis (PD) have been published. Most of the current information is available through from either study with the limited number of patients or isolated case reports. We conducted an observational study of our PD-peritonitis database over the past 12 years to study the clinical profile and the outcomes of peritonitis episodes in our PD center. A total of 1123 patients (male: 59.5%) with 319 episodes of peritonitis were identified. Of the patients, 130 (11.6%) were considered immunocompromised (steroid use, failed renal transplant, systemic lupus erythematosus, malignancy) and 468 (41.7%) had diabetes mellitus. The total number of bacterial peritonitis episodes was 319; of these 226 (70.8%) were seen with double cuff Tenckhoff PD catheter and 93 (29.2%) occurred with triple-cuff Saudi PD catheter (P = 0.0001). Of all peritonitis episodes 170 (53.3%) episodes were caused by a single Gram-positive organism, 124 (38.9%) episodes by a single Gram-negative organism, and 25 (7.8%) were polymicrobial. Coagulase-negative staphylococci were responsible for most cases of Gram-positive peritonitis (n = 110, 64.7%), while Escherichia coli was the causative organism in 67 (54.0%) of the single Gram-negative episodes. Peritonitis episodes due to Gram-positive organisms had a better outcome than those caused by Gram-negative bacteria. Fifteen (4.7%) of the 319 episodes resulted in death in 13 patients. In 79 (24.8%) episodes, the patients had to be transferred to hemodialysis because of unresolved peritonitis. Resolution rate was 75.2% (240 episodes) which was influenced by PD catheter type, PD duration and the number of days peritoneal fluid effluent remained above 100 cells/µL. Other modifiable and non-modifiable factors had no effect on the resolution rate. Peritonitis episodes due to Gram-positive organisms had a better outcome than those with Gram-negative or polymicrobial etiology. Peritonitis resolution rates were worse with Staphylococcus aureus and Pseudomonas aeruginosa infections. Diabetes, current steroid use, and exit-site/tunnel infections seemed to have limited influence on the peritonitis outcome. Type of PD catheter (double Tenckhoff vs triple-cuff Saudi catheter), duration of PD and the number of days peritoneal fluid effluent remained >100 cells/µL were the only factors with significant effects on the outcome.


Subject(s)
Catheter-Related Infections/etiology , Catheters/adverse effects , Peritoneal Dialysis/adverse effects , Peritoneal Dialysis/instrumentation , Peritonitis/microbiology , Adult , Aged , Equipment Design , Female , Humans , Male , Middle Aged , Time Factors
12.
J Saudi Heart Assoc ; 32(2): 213-218, 2020.
Article in English | MEDLINE | ID: mdl-33154919

ABSTRACT

BACKGROUND: Tricuspid valve regurgitation may affect the outcomes after heart transplantation. There is a paucity of data reporting the outcomes of heart transplants in our region. The objectives of this study were to report the occurrence of tricuspid regurgitation after heart transplantation, its course, and its effect on survival. METHODS: From 2009 to 2019, 30 patients had heart transplantation at our cardiac center. Their age was 36.73 ± 13.5 years, and 25 (83.33%) were males. Indications for transplantation were dilated cardiomyopathy (n = 21; 72.41%), ischemic cardiomyopathy (n = 8; 26.67%) and hypertrophic cardiomyopathy (n = 1; 3.45%). Cardiopulmonary bypass time was 157.24 ± 34.6 min, and ischemic time was 138 ± 73.56 min. All patients had orthotopic heart transplantation with a bi-caval technique. RESULTS: Eleven patients had severe tricuspid regurgitation postoperatively (37%). The degree of tricuspid regurgitation decreased significantly after 6 months (p = 0.011) and remained stationary during the follow-up. Pre-transplant dilated cardiomyopathy was significantly associated with severe tricuspid regurgitation post-transplant (p = 0.017). The mean follow-up was 39.43 ± 50.57 months. Survival at 10 years was 90% in patients with less than moderate tricuspid regurgitation postoperatively compared to 43% for patients with moderate and severe tricuspid regurgitation (log-rank p = 0.0498). CONCLUSION: Tricuspid regurgitation is a common problem after heart transplantation. Despite the improvement of the degree of tricuspid regurgitation after 6 months, survival was negatively affected by postoperative moderate or severe tricuspid regurgitation. Patients with dilated cardiomyopathy may benefit from concomitant tricuspid valve repair at the time of heart transplantation. Further larger studies are warranted.

13.
J Int Soc Prev Community Dent ; 10(3): 300-308, 2020.
Article in English | MEDLINE | ID: mdl-32802776

ABSTRACT

AIMS AND OBJECTIVES: The aim of this study was to determine the levels of knowledge and attitude of dental practitioners (DPs) toward vital pulp therapy (VPT) of young permanent teeth in Riyadh city, Saudi Arabia. MATERIALS AND METHODS: A descriptive cross-sectional study was carried out by taking convenient sample of general DPs and specialist attending Saudi International Dental Conference, Riyadh, Saudi Arabia. A total of 200 DPs administered a structured, self-administered questionnaire to evaluate their knowledge and attitude toward VPT. The questionnaire comprised four parts: Part I: Characteristics of the study participants; Part II: Items related to indications and diagnosis of VPT; Part III: Questions related to the different VPTs for immature permanent teeth; and Part IV: Dental materials used in VPT and restoration. All the data were entered into the statistical analysis software Statistical Package for the Social Sciences version 21.0 (IBM, Armonk, NY) and analyzed by using descriptive statistics of frequency distribution and percentages for the categorical variables. RESULTS: A total of 193 (men = 57% [110] and women = 43% [83]) DPs participated in this study with a response rate of 96.5%. Less than half of correct responses were observed with (Item 1) related to the duration of complete closure of root apex (43%) and (Item 14) use of sodium hypochlorite to serve as an excellent diagnostic tool to differentiate irreversible from reversible pulpitis. A high percentage of correct responses were seen with the (Item 9) indirect pulp capping--a procedure performed in a tooth with a deep carious lesion without signs or symptoms of pulp degeneration (75%). All other item responses ranged in between 52% and 72%. CONCLUSION: DPs showed fair-to-good knowledge and attitude toward VPT of young permanent teeth. In general, there is a need to improve knowledge and attitude of dental professionals about the VPT by attending continuing dental educational programs.

14.
J Card Surg ; 35(7): 1717-1720, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32598498

ABSTRACT

We present a 57-year-old man with recent Streptococcus viridans endocarditis on mitral and aortic valves who had a mycotic aneurysm of the left anterior descending (LAD) coronary artery and associated superior mesenteric and cerebral artery aneurysms. The patient had preoperative renal failure and the infection was controlled with ceftriaxone. Mitral and aortic valve replacement were performed using tissue valves and the LAD aortic aneurysm was ligated and the patient had saphenous venous graft to the LAD. The postoperative course was complicated by pleural effusion and the patient had antibiotic therapy for 6 weeks postoperatively.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Aortic Valve/surgery , Coronary Aneurysm/etiology , Coronary Aneurysm/surgery , Coronary Artery Bypass/methods , Coronary Vessels/surgery , Endocarditis, Bacterial/complications , Endocarditis, Bacterial/surgery , Heart Valve Diseases/complications , Heart Valve Diseases/surgery , Mitral Valve/surgery , Endocarditis, Bacterial/microbiology , Heart Valve Diseases/microbiology , Heart Valve Prosthesis Implantation/methods , Humans , Ligation/methods , Male , Middle Aged , Postoperative Care , Saphenous Vein/transplantation , Streptococcal Infections , Treatment Outcome , Viridans Streptococci
15.
J Family Med Prim Care ; 8(11): 3763-3765, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31803689

ABSTRACT

Canine is the cornerstone of the mouth due to its position, which reflects its significance of mastication with incisors and premolars. Anomalous root canal morphology can be found in any tooth with different degrees. The unusual configuration of root canal system may lead to a lot of procedural errors during cleaning and shaping, and this, in turn, may increase the probability of root canal treatment failure. In most cases, mandibular canines have one root of a centrally located root canal and 15% of this type of tooth has two root canals.

16.
Sci Rep ; 8(1): 3617, 2018 02 26.
Article in English | MEDLINE | ID: mdl-29483601

ABSTRACT

Sequential chemical extraction and synchrotron-based XANES spectroscopy techniques were used to identify P species in two ashes before and after addition to a prairie soil. The used ashes were: meat and bone meal ash (MBMA) and dried distillers grains ash (DDGA) plus mineral P fertilizer (MP) for comparison. Soil treated with MP contained higher content of resin-Pi and NaHCO3-Pi followed by DDGA and MBMA. The MBMA amended soil had the highest (47%) proportion of the soil P contained in recalcitrant HCl extractable fraction, reflecting more Ca-bound P present and being formed in soil after application. Analysis of both ashes with XANES spectroscopy before application to soil revealed that MBMA had strong spectral features consistent with hydroxyapatite (Ca5(PO4)3(OH)). DDGA exhibited spectral features consistent with a mixture of several Mg and K phosphate salts rather than a single mineral species. The distinctive features in the XANES spectra of both ashes largely disappeared after amendment to the soil, suggesting transformation to different P forms in the soil after application. It is also possible that the added amount of P to the studied soil via DDGS or MBMA was small enough so that P speciation is not different from the background P level.

17.
Psychol Rep ; 118(3): 902-17, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27140651

ABSTRACT

This study examined the psychometric properties of the Arabic version of Abbott's Creative Self-Efficacy inventory. Saudi honors students (157 men vs. 163 women) participated. These students are undergraduates (M age = 19.5 year, SD = 1.9) who complete 30 credit hours with a grade point average of no less than 4.5 out of 5. The results showed that the internal consistency (α = .87) and the test-retest reliabilities (r = .73) were satisfactory. The study sample was separated into two subsamples. The data from the first subsample (n = 60) were used to conduct an exploratory factor analysis, whereas the data from the second subsample (n = 260) were used to perform a confirmatory factor analysis. The results of exploratory factor analysis and confirmatory factor analysis indicated that creative self-efficacy was not a unidimensional construct but consisted of two factors labeled "creative thinking self-efficacy" and "creative performance self-efficacy." As expected, this two-factor model fit the data adequately, supporting prior research that treated creative self-efficacy as multidimensional construct.


Subject(s)
Creativity , Psychometrics/instrumentation , Self Efficacy , Surveys and Questionnaires/standards , Adult , Female , Humans , Male , Saudi Arabia , Students , Universities , Young Adult
18.
Nurse Educ Today ; 36: 249-54, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26586258

ABSTRACT

BACKGROUND: There has been some ground-breaking research on self-directed learning (SDL) in nursing education which reveals the superiority of SDL to traditional learning methods in terms of students' academic performance and the development of positive attitudes toward the learning process on the part of both students and teachers. OBJECTIVES: The relationship between students' self-directed learning readiness (SDLR) and students' academic performance, and the mediating role of students' perceptions of the learning environment needs further investigation. In this study, it is proposed that students' perceptions of their learning environment could enhance their SDLR and thus boost their academic performance (in terms of their GPA). DESIGN: A descriptive design was used to examine the relationships between the domains of SDLR, which are self-management, desire to learn and self-control and students' perceptions of the learning environment (SPLE) and students' GPA. DATA SOURCE: A survey involving 342 [Corrected] Saudi students from nursing and emergency medical services undergraduate programs in King Saud University was used for this research. RESULTS: The results showed that SDLR level positively influenced students' academic performance positively, and that students' perceptions of their learning environment played a significant role in determining their level of SDLR and academic performance. CONCLUSION: It is recommended that nursing and emergency medical services educators provide a supportive learning environment in terms of good teaching, clear goals and standards, appropriate assessment, appropriate workload, and emphasis on independence to encourage students to engage in the process of SDL which can, in turn, enhance their academic performance.


Subject(s)
Emergency Medicine , Learning , Students, Medical , Students, Nursing , Cross-Sectional Studies , Saudi Arabia , Workforce
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