On-orbit assembly using superquadric potential fields

The autonomous on-orbit assembly of a large space structure is presented using a method based on superquadric artificial potential fields. The final configuration of the elements which form the structure is represented as the minimum of some attractive potential field. Each element of the structure is then considered as presenting an obstacle to the others using a superquadric potential field attached to the body axes of the element. A controller is developed which ensures that the global potential field decreases monotonically during the assembly process. An error quaternion representation is used to define both the attractive and superquadric obstacle potentials allowing the final configuration of the elements to be defined through both relative position and orientation. Through the use of superquadric potentials, a wide range of geometric objects can be represented using a common formalism, while collision avoidance can make use of both translational and rotation maneuvers to reduce total maneuver cost for the assembly process

Ultrasonographic Diagnosis and Clinical Evaluation of the Foreign Body Complications in the Compound Stomach of Cattle and Buffaloes

This study was aimed to detect and record the clinical and ultrasonographic findings of the different complications resulted from the foreign bodies lodged in the compound stomach of cattle and buffaloes. A total of 105 animals (37 cattle and 68 buffaloes) were subjected to study. Based on the clinical and ultrasonographic examination, animals were classified into; acute local reticuloperitonitis (ALRP) (15 cattle and 28 buffaloes), chronic local reticuloperitonitis (CLRP) (6 cattle and 14 buffaloes), acute diffuse reticuloperitonitis (ADRP) (5 cattle and 3buffaloes), reticular abscesses (RA) (4 cattle and 7 buffaloes), traumatic pericarditis (TP) (6 cattle and16 buffaloes) and liver abscess (one cattle). Results revealed that ALRP represented the highest percentage of 40.5% in cattle and 41.2 % in buffalos between the different complications of TRP. TP represented the second complications of higher incidence (16.2% in cows and 23.5% in buffalos). Liver abscess represented the lowest percentage (2.8%) and was recorded in cows only. The pregnant animals were affected more than the non pregnant. Clinical findings represented in systemic reaction and pain tests were commonly encountered in TRP and its complications. Some of the affected animals were negatively respond to metal detector test. Results of the present study indicated that the ultrasonographic examination provide a specific echogenic pattern for the different complications of TRP. It was concluded that, clinical examination only is not efficient to give accurate diagnosis of foreign body lodged in the reticulum and rumen and their complications. Ultrasonography is a safe, non invasive diagnostic confirmatory method that could be used for early detection of such conditions

Effect of Blended Learning Approach on Student Nurses’ Attitudes and Academic Achievement

Although  various blended approaches that integrate online components into traditional classes continue to grow rapidly, they still remain at an early stage of development. Consequently, developers and deliverers of online learning need more understanding of how students perceive and react to elements of e-learning (since student perception and attitude is critical to motivation and learning) along with how to apply these approaches most effectively to enhance learning. The Aim: aim of the current study was to examine the effect of blended learning  approach on student nurses’ attitudes and academic achievement in Medical Surgical Nursing course compared to traditional teaching method modules. Setting: A The sample consisted of 62 female students their age range from 19 to 20 years at 5th., level  recruited from 5th., level in faculty of nursing, King Khaled University   Tools: 3  tools used to collect data for the study: 1. student attitude scale toward blended learning approach 2.A Constructed Motivational Scale. and The Achievement Test, they are developed by the researchers. Results: The study findings revealed that,  the Study Group subjects (blended learning Group ) had higher Mean Of attitude  Subscales And Total Scores, achievement test Scores, and Mean Of Motivational Subscales And Total Scores than  Control Group (traditional), in addition, there were  statistically significant differences were found between the two groups in relation to previously mentioned variables. Therefore, this study recommended an educational programs for academic staff for teaching using  blended learning approach. Keywords: E-learning, Online learning, traditional, Attitudes, Blended Learning, Academic Achievement

Autonomous three-dimensional formation flight for a swarm of unmanned aerial vehicles

This paper investigates the development of a new guidance algorithm for a formation of unmanned aerial vehicles. Using the new approach of bifurcating potential fields, it is shown that a formation of unmanned aerial vehicles can be successfully controlled such that verifiable autonomous patterns are achieved, with a simple parameter switch allowing for transitions between patterns. The key contribution that this paper presents is in the development of a new bounded bifurcating potential field that avoids saturating the vehicle actuators, which is essential for real or safety-critical applications. To demonstrate this, a guidance and control method is developed, based on a six-degreeof-freedom linearized aircraft model, showing that, in simulation, three-dimensional formation flight for a swarm of unmanned aerial vehicles can be achieved

Novel Sequence Variants in the NPC1 Gene in Egyptian Patients with Niemann-Pick Type C

BACKGROUND: Niemann-Pick disease type C (NPC) is a rare, autosomal recessive, progressive neuro-visceraldisease caused by biallelic mutations in either NPC1gene (95% of cases) or NPC2 gene. AIM: This caseseries study aimed at the molecular analysis of certain hot spots of NPC1 genein NPC Egyptian patients. METHODS: The study included 15 unrelated NPC patients and selected parents,as well as20 healthy controls of matched sex and age. Clinical investigations were performed according to well established clinical criteria. Assessment of the chitotriosidase level, as an initial screening tool for NPC, was done in all cases. Polymerase chain reaction amplification of NPC1 exons (17–25) encountering the hotspot residues (855–1098 and1038–1253) was carried out followed by direct sequencingfor mutational analysis. RESULTS: All includedpatients with mainly neurovisceral involvement were characterized. The onset of the disease varied from early-infantile (58.3%) to late-infantile (26.7%) and juvenile-onset (6.7%). Ahigh chitotriosidase level wasobservedin all patients. Molecular analysis of NPC1 (exons 17–25) confirmed 15 mutant alleles out of 30 studied ones. They included two novel homozygous missense variants (p.Ser1169Arg and p.Ser1197Phe) and previously reportedfour mutations (p.Arg958*, p.Gly910Ser, p.Ala927Glyfs*38, and andp.Cys1011*). CONCLUSION: The two studied amino acid residues (855–1098 and 1038–1253) could beconsidered aspotential hotspot regions in NPC1 Egyptian patients

Vasoactive pharmacologic therapy in cardiogenic shock: a critical review.

Cardiogenic shock (CS) is an acute complex condition leading to morbidity and mortality. Vasoactive medications, such as vasopressors and inotropes are considered the cornerstone of pharmacological treatment of CS to improve end-organ perfusion by increasing cardiac output (CO) and blood pressure (BP), thus preventing multiorgan failure. A critical review was conducted to analyze the currently available randomized studies of vasoactive agents in CS to determine the indications of each agent and to critically appraise the methodological quality of the studies. PubMed database search was conducted to identify randomized controlled trials (RCTs) on vasoactive therapy in CS. After study selection, the internal validity of the selected studies was critically appraised using the three-item Jadad scale. Nine studies randomized 2388 patients with a mean age ranged between 62 and 69 years, were identified. Seven of studies investigated CS in the setting of acute myocardial infarction (AMI). The studies evaluated the comparisons of norepinephrine (NE) dopamine, epinephrine NE, levosimendan dobutamine, enoximone or placebo, and nitric oxide synthase inhibitors (NOSi) placebo. The mean Jadad score of the nine studies was 3.33, with only three studies of a score of 5. The evidence from the studies of vasoactive agents in CS carries uncertainties. The methodological quality between the studies is variable due to the inherent difficulties to conduct a study in CS. Vasopressors and inotropes continue to have a fundamental role given the lack of pharmacological alternatives

Lysozyme as an alternative to antibiotics improves growth, antioxidants status, immunity, and intestinal bacteria in broiler chickens during the fattening period

The present study aimed to evaluate the impact of dietary lysozyme levels on the growth performance, hematological and blood biochemical parameters, immunity, antioxidant capacity, and intestinal microbial count in broiler chickens. Three-hundred 1 d old birds (Cobb-avian500) were used and divided into five groups (five replicates per group, 60 birds per replicate). Birds in the first group were fed a control diet, while birds in the second, third, fourth, and fifth groups were fed the control diet with 0.2 g lincomycin, 1 g commercial lysozyme, 25 mg chicken egg lysozyme, and 50 mg egg lysozyme per kg of diet, respectively. Results confirmed that, in comparison with the control diet, all supplements had greater impacts on final body weight and body weight gain, and only the egg lysozyme diet (50 mg kg−1 diet) increased feed intake. Lincomycin, commercial lysozyme, and egg lysozyme (25 mg) improved the feed conversion ratio (FCR). Birds fed commercial lysozyme and egg lysozymes showed significantly increased hemoglobin and red blood cell counts. All supplements reduced white blood cells, heterophils, and heterophils / lymphocytes ratio and increased lymphocytes. All supplements significantly increased serum total protein, albumin, globulin, and glucose. The diet of egg lysozyme (50 mg kg−1) significantly decreased alpha-globulin, alanine aminotransferase, triglycerides, cholesterol, and urea levels and increased high-density lipoproteins. Diets with lincomycin, commercial lysozyme, and egg lysozyme significantly increased antioxidant capacity and decreased malondialdehyde (MDA). The interferon-gamma (IFNγ) and interlukin-2 (IL-2) were significantly improved by lincomycin, commercial lysozyme and egg lysozyme diets, but interlukin-10 (IL-10) was significantly increased only by the egg lysozyme (50 mg kg−1) diet. The total bacterial count, Salmonella, Escherichia coli, and Proteus counts were significantly decreased. Dressing rate and breast weight percentage were significantly increased by the egg lysozyme (50 mg kg−1) diet. Thigh weight percentage was increased only by the commercial lysozyme diet. In conclusion, chicken egg lysozyme (50 mg kg−1), a promising alternative for antibiotics in broiler chickens' diet, can enhance growth performance, antioxidant status, immunity, and intestinal bacteria.</p

Earthquake source parameters and scaling relationships in Hungary (central Pannonian basin)

Abstract Fifty earthquakes that occurred in Hungary (central part of the Pannonian basin) with local magnitude ML ranging from 0.8 to 4.5 have been analyzed. The digital seismograms used in this study were recorded by six permanent broad-band stations and twenty short-period ones at hypocentral distances between 10 and 327 km. The displacement spectra for P- and SH-waves were analyzed according to Brune’s source model. Observed spectra were corrected for path-dependent attenuation effects using an independent regional estimate of the quality factor QS. To correct spectra for near-surface attenuation, the k parameterwas calculated, obtaining it fromwaveforms recorded at short epicentral distances. The values of the k parameter vary between 0.01 to 0.06 s with a mean of 0.03 s for P-waves and between 0.01 to 0.09 s with a mean of 0.04 s for SH-waves. After correction for attenuation effects, spectral parameters (corner frequency and low-frequency spectral level) were estimated by a grid search algorithm. The obtained seismic moments range from4.21×1011 to 3.41×1015 Nm (1.7≤Mw ≤4.3). The source radii are between 125 and 1343 m. Stress drop values vary between 0.14 and 32.4 bars with a logarithmic mean of 2.59 bars (1 bar = 105 Pa). From the results, a linear relationship between local andmomentmagnitudes has been established. The obtained scaling relations show slight evidence of self-similarity violation. However, due to the high scatter of our data, the existence of self-similarity cannot be excluded