148 research outputs found

    Effect of water harvesting methods, nitrogen and phosphorus fertilizer rate on number of leaves of different date palm (phoenix d-) varieties

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    A field experiment was conducted to study the effect of water harvesting methods, NP - fertilizer rate on leaf number of some young date palm plants over a period of 32 months (May 2004- December 2006).The trial was sited at the Date palm Research Sub-station of the Nigerian Institute for Oil palm Research (NIFOR) Dutse (11o50’N, 09o25’E) in the Sudan savanna ecological zone of Nigeria. The treatments consisted of six water harvesting methods (standard 30cm radius basin, single side pit, double side pits, perimeter square basin, side square basin and double square basin). Six NP-fertilizer rates (control which is zero level fertilizer, 20g N + 10g P, 40g N + 20g P, 60g N + 30g P, 80g N + 40g P and 100g N + 50g P) and six date palm varieties (Palm 300, Tirgal, Dan Mali, Deglet Noor, Shuwarin C and Shuwarin B) arranged in a Latin square design. Two plants per experimental plot were sampled for plant leaf number, giving a total of 72 plants. Results from this study revealed that the effects due of varying water harvesting methods were not significant on leaf number. The effects due to varying NP-fertilizer rates were also not significant on leaf number. A three year experiment was not long enough to cause pronounced effects. Deglet Noor and Dan Mali significantly recorded more leaf number while Shuwarin B, Tirgal and Palm 300 recorded the lowest leaf number. Application of NP- fertilizer at rates 80- 100g N and 40- 50g P/ plant/year on a three year Deglet Noor or Dan Mali date palm variety will enhance plant leaf number and yield and may be recommended for better date palm production, within the Sudan ecological zone of Nigeria where this experiment was conducted, following further studies

    Copolymerazaion of N-vinyl-2-pyrrolidon with Acrylic Acid and Methylmethacrylate

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    Low conversion copolymerization of N-vinyl-2-pyrrolidon M.W = (111.14) VP (monomer-1) has been conducted with acrylic acid AA and methymethacrylate MMA in ethanol at 70ºC , using Benzoyl peroxide BPO as initiator . The copolymer composition has been determined by elemental analysis. The monomer reactivity ratios have been calculated by the Kelen-Tudos and Finman-Ross graphical procedures . The derived reactivity ratios (r1 , r2 ) are : (0.51 , 4.85) for (VP / AA ) systems and (0.34 , 7.58) for (VP , MMA) systems , and found the reactivity ratios of the monomer AA , MMA is mor than the monomer VP in the copolymerization of (VP / AA) and (VP /MMA) systems respectly . The reactivity ratios values were used for microstructures calculation

    THE RELATIONSHIP BETWEEN INTRUSIVE COGNITIONS AND DEFENSE MECHANISMS IN HEALTHY AND CLINICAL POPULATIONS

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    Purpose: to examine the relationship between defense mechanisms and intrusive cognitions in normal healthy individuals and psychiatric patients. Methodology: The study sample consists of a healthy group (n=60; 30 males & 30 females), whereas the clinical group (n=66; 34 males, 32 females) includes patients with major depressive disorder (12 patients, 5 males, 7 females), schizophrenia (31 patients; 14 males, 17 females), obsessive-compulsive disorder (23 patients; 15 males, 8 females). We used several scales to measure the following variables: intrusive cognitions, intrusive memories, and defense mechanisms. Finding: The results show that there is a positive correlation between defense mechanisms and intrusive cognitions in healthy and clinical groups. Intrusive cognitions were more common in the patient than in a healthy group. Furthermore, there was no significant difference between males and females in measures of intrusive thoughts and memories in both groups. Implications: These findings have implications for behavioral treatment. Treatments used for managing posttraumatic stress disorder can also be used for the treatment of a major depressive disorder, OCD, and schizophrenia. Originality: This investigation the relationship between intrusive cognitions and defense mechanisms in healthy and clinical populations and its implication on the cue exposure therapy that can be the treatment of intrusive cognitions and thoughts in with major depressive disorder, OCD, and schizophrenia

    Stress and Its Effects on Medical Students: A Cross-sectional Study at a College of Medicine in Saudi Arabia

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    Medical education is perceived as being stressful, and a high level of stress may have a negative effect on cognitive functioning and learning of students in a medical school. This cross-sectional study was conducted to determine the prevalence of stress among medical students and to observe an association between the levels of stress and their academic performance, including the sources of their stress. All the medical students from year one to year five levels from the College of Medicine, King Saud University, were enrolled in the study. The study was conducted using Kessler10 psychological distress (K10) inventory, which measures the level of stress according to none, mild, moderate, and severe categories. The prevalence of stress was measured and compared with the five study variables, such as gender, academic year, academic grades, regularity to course attendance, and perceived physical problems. The response rate among the study subjects was 87% (n=892). The total prevalence of stress was 63%, and the prevalence of severe stress was 25%. The prevalence of stress was higher (p<0.5) among females (75.7%) than among males (57%) (odds ratio=2.3, χ2=27.2, p<0.0001). The stress significantly decreased as the year of study increased, except for the final year. The study variables, including being female (p<0.0001), year of study (p<0.001), and presence of perceived physical problems (p<0.0001), were found as independent significant risk factors for the outcome variables of stress. Students' grade point average (academic score) or regularity to attend classes was not significantly associated with the stress level. The prevalence of stress was higher during the initial three years of study and among the female students. Physical problems are associated with high stress levels. Preventive mental health services, therefore, could be made an integral part of routine clinical services for medical students, especially in the initial academic years, to prevent such occurrence

    Study of obesity associated proopiomelanocortin gene polymorphism: Relation to metabolic profile and eating habits in a sample of obese Egyptian children and adolescents

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    AbstractBackgroundMelanocortinergic system represents a known system involved in the central regulation of body weight with the central proopiomelanocortin (POMC) neurons forming a potent anorexigenic network. Polymorphisms in the POMC gene locus are associated with obesity phenotypes.AimTo assess the contribution of the POMC gene 9-bp insertional polymorphism in the susceptibility to obesity and its relation to body mass index (BMI) and adiposity-related co-morbidities in obese children and adolescents; as well as binge eating behavior.Patients and methodsFifty obese children and adolescents with simple obesity were screened for Binge Eating Disorder (BED) by The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), they were compared to 50 age, sex and pubertal stage-matched non obese controls. Anthropometric measurements, blood pressure, abdominal ultrasound for fatty liver, measurement of fasting lipid profile, fasting insulin, fasting blood glucose and assessment of POMC gene 9-bp insertional polymorphism were done.ResultsObese patients had significantly higher anthropometric measurements, blood pressure percentiles, fasting glucose, fasting insulin, homeostasis model assessment for insulin resistance (HOMA-IR) and fasting lipid profiles, and higher frequency of occurrence of non alcoholic fatty liver disease and BED. Allelic frequencies of POMC gene 9bp insertional polymorphism were comparable in patients and controls (p=0.956). Fasting insulin levels were significantly higher in the heterozygous cases having the polymorphism than in wild homozygous cases; whereas no difference was observed among the controls.ConclusionThis polymorphism was associated with higher fasting insulin levels in the obese patients only. These findings support the hypothesis that the melanocortin pathway may modulate glucose metabolism in obese subjects indicating a possible gene-environment interaction. POMC variant may be involved in the natural history of polygenic obesity, contributing to the link between type 2 diabetes and obesity

    Lean partially premixed turbulent flame equivalence ratio measurements using laser-induced breakdown spectroscopy

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    The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.The creation of a more stable flame along with the extension of flammability limits under lean mixture combustion was the main motivation to develop a new burner design, which has been investigated in this research. The current burner configuration was utilized to create a wide range of higher turbulent intensities and to produce different degrees of mixture inhomogeneity, which acted to promote minimum pollution, highest performance and higher flame stability. The burner stability assessment was investigated using two types of fuel: natural gas (NG) and liquefied petroleum gas (LPG). They were tested under different degrees of partial premixing, and two turbulence generator disks for lean mixture at an equivalence ratio of φ = 0.8 were used. Following this, the Laser Induced Breakdown Spectroscopy (LIBS) technique was utilized to characterize and quantify the impact of changing the disk slit diameter on the distributions profiles of equivalence ratio or mixture fraction for a NG/air partially premixed flame. A series of homogeneous NG/air mixtures with different equivalence ratios were used to obtain the correlations between the measured emission lines of LIBS spectra and the global flame equivalence ratio. Consequently, the emission spectral lines ratios of H/N, H/O and C/N + O were utilized to predict the equivalence ratio distributions. The results demonstrated that for all of the mixing lengths, NG/air mixture with larger disk generator diameter yielded the maximum burner stability, whilst the LPG/air mixture with a larger disk generator diameter resulted in the minimum burner stability. Furthermore, the flame associated with the larger disk slit diameter had a uniform local equivalence ratio distribution and lower RMS fluctuation profiles of equivalence ratio in comparison to the lower disk slit diameter

    Potentially toxic elements in saltmarsh sediments and common reed (Phragmites australis) of Burullus coastal lagoon at North Nile Delta, Egypt: A survey and risk assessment

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    Burullus lagoon is the second largest lake in Egypt. However, there has never been a comprehensive survey which studied nineteen potentially toxic elements in sediments and plants and evaluated the associated potential risk. Thus, we aimed to study the total and potentially available content of As, Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Sb, Se, Sn, Tl, V, and Zn in the sediments and common reed (Phragmites australis) at thirty two sites along the entire lagoon and connected drains. Contamination Factor (CF), Pollution Load Index (PLI), Geo-accumulation Index (Igeo), and Enrichment Factor (EF) were calculated to assess the grade of contamination. Element accumulation factor (AF) and bio-concentration ratio (BCR) were also calculated. Aluminum showed the highest median (mg kg−1) total content (41,200), followed by Fe (30,300), Mn (704.7), V (82.0), Zn (75.5), Cr (51.2), Cu (47.8), Ni (44.3), As (31.9), Tl (24.6), Co (21.4), Se (20.3), Sb (17.6), Sn (15.6), Mo (11.3), and Hg (16.6 μg kg−1). Values of the EF, CF, and Igeo showed that the sediments were heavily contaminated with As, Sb, Se, Tl, Mo, Sn, Co, Ni, and Cu. The drained sediment had significantly higher values of total and potentially available element content than the lagoon sediments. Sediments of the middle and western area showed significantly higher contents of total and available elements than the eastern section. The BCR and AF values indicate that the studied plant is efficient in taking up high amounts of Zn, Fe, As, Sn, Tl, Ni, Mo, Mn; then Co, Cu, and V. The results exhibit a dramatic contamination at certain sites of the lagoon, and the studied PTEs have a predominant role in contamination-related ecological risk. Further investigations concerning redox-induced mobilization of PTEs in sediments, the risk of fish contamination and the potential health hazards are highly recommended

    Stress and Its Effects on Medical Students: A Cross-sectional Study at a College of Medicine in Saudi Arabia

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    Medical education is perceived as being stressful, and a high level of stress may have a negative effect on cognitive functioning and learning of students in a medical school. This cross-sectional study was conducted to determine the prevalence of stress among medical students and to observe an association between the levels of stress and their academic performance, including the sources of their stress. All the medical students from year one to year five levels from the College of Medicine, King Saud University, were enrolled in the study. The study was conducted using Kessler10 psychological distress (K10) inventory, which measures the level of stress according to none, mild, moderate, and severe categories. The prevalence of stress was measured and compared with the five study variables, such as gender, academic year, academic grades, regularity to course attendance, and perceived physical problems. The response rate among the study subjects was 87% (n=892). The total prevalence of stress was 63%, and the prevalence of severe stress was 25%. The prevalence of stress was higher (p&lt;0.5) among females (75.7%) than among males (57%) (odds ratio=2.3, \u3c72=27.2, p&lt;0.0001). The stress significantly decreased as the year of study increased, except for the final year. The study variables, including being female (p&lt;0.0001), year of study (p&lt;0.001), and presence of perceived physical problems (p&lt;0.0001), were found as independent significant risk factors for the outcome variables of stress. Students\u2019 grade point average (academic score) or regularity to attend classes was not significantly associated with the stress level. The prevalence of stress was higher during the initial three years of study and among the female students. Physical problems are associated with high stress levels. Preventive mental health services, therefore, could be made an integral part of routine clinical services for medical students, especially in the initial academic years, to prevent such occurrence

    Optimal deep learning driven intrusion detection in SDN-Enabled IoT environment

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    In recent years, wireless networks are widely used in different domains. This phenomenon has increased the number of Internet of Things (IoT) devices and their applications. Though IoT has numerous advantages, the commonly-used IoT devices are exposed to cyber-attacks periodically. This scenario necessitates real-time automated detection and the mitigation of different types of attacks in high-traffic networks. The Software-Defined Networking (SDN) technique and the Machine Learning (ML)-based intrusion detection technique are effective tools that can quickly respond to different types of attacks in the IoT networks. The Intrusion Detection System (IDS) models can be employed to secure the SDN-enabled IoT environment in this scenario. The current study devises a Harmony Search algorithm-based Feature Selection with Optimal Convolutional Autoencoder (HSAFS-OCAE) for intrusion detection in the SDN-enabled IoT environment. The presented HSAFS-OCAE method follows a three-stage process in which the Harmony Search Algorithm-based FS (HSAFS) technique is exploited at first for feature selection. Next, the CAE method is leveraged to recognize and classify intrusions in the SDN-enabled IoT environment. Finally, the Artificial Fish Swarm Algorithm (AFSA) is used to fine-tune the hyperparameters. This process improves the outcomes of the intrusion detection process executed by the CAE algorithm and shows the work’s novelty. The proposed HSAFS-OCAE technique was experimentally validated under different aspects, and the comparative analysis results established the supremacy of the proposed model
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