48 research outputs found
Solid Pseudopapillary Tumor of the Pancreas: A Case Report
Introduction: Solid pseudopapillary tumor (SPT) of the pancreas is rare, accounting for 0.13-2.7% of all pancreatic tumors. It has specific clinical, pathological and radiological characters that make it quite different from other pancreatic tumors.Presentation of case: A 15-year-old girl with SPT of the pancreas diagnosed after surgical resection with histopathology and immunohistochemistry confirmation. As no clear role for adjuvant treatment, she was elected for follow up.Conclusion: Although SPT is a rare tumor without notable symptoms. Complete surgical excision is the treatment of choice. The place of chemotherapy or radiotherapy needed to be elucidated
First evidence for human occupation of a lava tube in Arabia: The archaeology of Umm Jirsan Cave and its surroundings, northern Saudi Arabia
Recent advances in interdisciplinary archaeological research in Arabia have focused on the evolution and historical development of regional human populations as well as the diverse patterns of cultural change, migration, and adaptations to environmental fluctuations. Obtaining a comprehensive understanding of cultural developments such as the emergence and lifeways of Neolithic groups has been hindered by the limited preservation of stratified archaeological assemblages and organic remains, a common challenge in arid environments. Underground settings like caves and lava tubes, which are prevalent in Arabia but which have seen limited scientific exploration, offer promising opportunities for addressing these issues. Here, we report on an archaeological excavation and a related survey at and around Umm Jirsan lava tube in the Harrat Khaybar, north-western Saudi Arabia. Our results reveal repeated phases of human occupation of the site ranging from at least the Neolithic through to the Chalcolithic/Bronze Age. Pastoralist use of the lava tube and surrounding landscape is attested in rock art and faunal records, suggesting that Umm Jirsan was situated along a pastoral route linking key oases. Isotopic data indicates that herbivores primarily grazed on wild grasses and shrubs rather than being provided with fodder, while humans had a diet consistently high in protein but with increasing consumption of C3 plants through-time, perhaps related to the emergence of oasis agriculture. While underground and naturally sheltered localities are globally prominent in archaeology and Quaternary science, our work represents the first such combined records for Saudi Arabia and highlight the potential for interdisciplinary studies in caves and lava tubes
Homo sapiens in Arabia by 85,000 years ago.
Understanding the timing and character of the expansion of Homo sapiens out of Africa is critical for inferring the colonization and admixture processes that underpin global population history. It has been argued that dispersal out of Africa had an early phase, particularly ~130-90 thousand years ago (ka), that reached only the East Mediterranean Levant, and a later phase, ~60-50 ka, that extended across the diverse environments of Eurasia to Sahul. However, recent findings from East Asia and Sahul challenge this model. Here we show that H. sapiens was in the Arabian Peninsula before 85 ka. We describe the Al Wusta-1 (AW-1) intermediate phalanx from the site of Al Wusta in the Nefud desert, Saudi Arabia. AW-1 is the oldest directly dated fossil of our species outside Africa and the Levant. The palaeoenvironmental context of Al Wusta demonstrates that H. sapiens using Middle Palaeolithic stone tools dispersed into Arabia during a phase of increased precipitation driven by orbital forcing, in association with a primarily African fauna. A Bayesian model incorporating independent chronometric age estimates indicates a chronology for Al Wusta of ~95-86 ka, which we correlate with a humid episode in the later part of Marine Isotope Stage 5 known from various regional records. Al Wusta shows that early dispersals were more spatially and temporally extensive than previously thought. Early H. sapiens dispersals out of Africa were not limited to winter rainfall-fed Levantine Mediterranean woodlands immediately adjacent to Africa, but extended deep into the semi-arid grasslands of Arabia, facilitated by periods of enhanced monsoonal rainfall
Two new species of the Fusarium fujikuroi species complex isolated from the natural environment
Heat-Transfer Enhancement Incorporating Fin-Like Structures Inside Droplet on Hydrophobic Surface
Double primary cancers registered in a tertiary care hospital: review of two cases
In our centre, among 1965 registered cancer patients between May 2011 and December 2013, we report three cases with multiple primary malignant neoplasms. One of them was excluded due to lack of data, and so we present the remaining two cases. The first case is an 82-year-old female patient with colon and thyroid cancer and the second case is a 61-year-old female patient with colon and breast cancer. Both cases were metachronous and discovered accidently during the regular follow up, and managed with a curative intent. Conclusion: It is important for the clinicians to keep in mind that individuals with cancer are at increased risk for subsequent primary malignancies, which must be differentiated from recurrent or metastatic disease
Removal of Cr(VI) and Toxic Ions from Aqueous Solutions and Tannery Wastewater Using Polymer-Clay Composites
Polymer-clay composites were prepared by natural zeolite (clinoptilolite) or naturally local clay deposits in an N,N-methylene-bis-acrylamide as cross-linked. The resultant composites were used for the removal of Cr(VI) from an aqueous solution. Additionally, their effects on soluble ions of tannery wastewater were investigated. The produced composites were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The results showed that Cr(VI) removal is dependent upon initial concentrations and pH. The adsorption quantity of Cr(VI) onto the polymerized clay deposit followed by polymerized zeolite exhibited higher values than their original samples. The polymer-clay composite of clay deposit showed the highest removal of 76.3–100% overall initial concentrations of 10–50 mg L−1 and at initial pH of 2. Kinetics of Cr(VI) removal by various sorbents was predicted using a pseudo–second order model. Our findings showed that the levels of salinity and various soluble ions (Cr2+, Na+, Cl− and SO42−) in tannery wastewater are very high, and their levels were reduced after treatment, especially by polymerized sorbents. It could be concluded that the polymer-clay composites may be employed as a highly efficient sorbent for the removal of Cr(VI) and toxic ions from the wastewater
Four successful pregnancies in a patient with Fontan palliation and congenital heart disease: a case report
Abstract Background Fontan is a palliative procedure in patients with single ventricle. Single ventricle supports systemic cardiac output and pulmonary blood flow is passively directed to the right pulmonary artery. Women with Fontan palliation are reported to have increased maternal risk during pregnancy. There are few reports of successful pregnancies in such cases. However data on these pregnancies is lacking, we consider this to be the first reported from kingdom of Saudi Arabia. Case presentation We present a 35-year-old woman from the Kingdom of Saudi Arabia who had Fontan surgery and who had four successful pregnancies and multiple miscarriages. She delivered live, low birth weight neonates. Conclusion This report provides an anecdotal evidence that pregnancy can be tolerated in an adequate Fontan patient with successful outcomes
Efficiency and cost optimization of a micro-inverter transformer
The high-frequency transformer design for switch mode power supplies consists of core and winding design. It is necessary to take the cost of power loss and core volume in the long term into consideration during selection of core size, shape and material to produce an efficient transformer. The proximity effect seen in the windings deteriorates the performance of the transformer and can be averted by using Litz wires and sandwich winding structure