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21.
Safeer Abbas Ali Ahmed Ayesha Waheed Wasim Abbass Muhammad Yousaf Sbahat Shaukat Hisham Alabduljabbar Youssef Ahmed Awad 《Materials》2022,15(10)
Recycled rubber waste (RW) is produced at an alarming rate due to the deposition of 1.5 billion scrap tires annually around the globe, which causes serious threats to the environment due to its open land filling issues. This study investigates the potential application of RW in concrete structures for mitigating the alkali–silica reaction (ASR). Various proportions of RW (5%, 10%, 15%, 20%, and 25%) partially replaced the used aggregates. RW was procured from a local rubber recycling unit. Cubes, prisms, and mortar bar specimens were prepared using a mixture design recommended by ASTM C1260 and tested for evaluating the compressive and flexural strengths and expansion in an ASR conducive environment for specimens incorporating RW. It was observed that the compressive and flexural strength decreased for specimens incorporating RW compared to that of the control specimens without RW. For example, an 18% and an 8% decrease in compressive and flexural strengths, respectively, were observed for specimens with 5% of RW by aggregates volume at 28 days. Mortar bar specimens without RW showed an expansion of 0.23% and 0.28% at 14 and 28 days, respectively, indicating the potential ASR reactivity in accordance with ASTM C1260. A decrease in expansion was observed for mixtures incorporating RW. Specimens incorporating 20% of RW by aggregate volume showed expansions of 0.17% at 28 days, within the limit specified by ASTM C1260. Moreover, specimens incorporating RW showed a lower reduction in compressive and flexural strengths under an ASR conducive environment compared to that of the control specimen without RW. Micro-structural analysis also showed significant micro-cracking for specimens without RW due to ASR. However, no surface cracks were observed for specimens incorporating RW. It can be argued that the use of RW in the construction industry assists in reducing the landfill depositing issues with the additional benefit of limiting the ASR expansion. 相似文献
22.
Meriem Haloua Nizar El Bouardi Badre Eddine Alami Youssef Alaoui Lamrani Mustapha Maaroufi Hinde El Fatemi Mohammed Ridal Meryeme Boubbou 《Radiology Case Reports》2022,17(8):2607
Hemangioma of the facial sinuses is a rare pathology, and given the lack of clinical specificity, the differential diagnosis with a malignant lesion often arises. We report the case of a 32-year-old patient who consulted for recurrent epistaxis of moderate severity. The preoperative diagnosis of a hemangioma of the left maxillary sinus was based on computed tomography and magnetic resonance imaging data, confirmed by the anatomopathological study of the surgical specimen, preceded by an embolization that facilitated the endoscopic surgical excision. 相似文献
23.
Arsalan Raza Imran Khan Rana Faisal Tufail Jana Frankovska Muhammad Umar Mushtaq Abdellatif Salmi Youssef Ahmed Awad Muhammad Faisal Javed 《Materials》2022,15(15)
To enhance the moisture damage performance of hot mix asphalt (HMA), treating the aggregate surface with a suitable additive was a more convenient approach. In this research, two types of aggregate modifiers were used to study the effect of moisture damage on HMA. Three different aggregate sources were selected based on their abundance of use in HMA. To study the impact of these aggregate modifiers on moisture susceptibility of HMA, the indirect tensile strength test and indirect tensile modulus test were used as the performance tests. Moisture conditioning of specimens was carried out to simulate the effect of moisture on HMA. The prepared samples’ tensile strength ratio (TSR) and stiffness modulus (Sm) results indicated a decrease in the strength of the HMA after moisture conditioning. After treating the aggregate surface with additives, an improvement was seen in dry and wet strength and stiffness. Moreover, an increasing trend was observed for both additives. The correlation between TSR and strength loss reveals a strong correlation (R2 = 0.7219). Also, the two additives indicate increased wettability of asphalt binder over aggregate, thus improving the adhesion between aggregate and asphalt binder. 相似文献
24.
Interactions between pregnancy and breast cancer are complex and paradoxical. Epidemiological data show that nulliparity and late full-term pregnancy increase breast cancer risk. By contrast, early full-term pregnancy and multiparity are thought to be the most effective means of decreasing lifetime breast cancer risk. Paradoxically, young women diagnosed with breast cancer during pregnancy have a higher risk of dying from their disease. Moreover, there is a transient increase in risk of breast cancer in the first three to four years after pregnancy. After breast cancer treatment, there is no evidence that pregnancy increases the risk of breast cancer recurrence. Thus, it is not contraindicated in women previously treated for breast cancer and free of recurrence. Various physio-pathological mechanisms are involved in the protective effect of pregnancy, like cellular differentiation of mammary cells, mammary gland involution, circulating anti-mucin antibody and excretion in the milk of breast carcinogens. In the past, unfavorable effects of pregnancy were mainly attributed to precancerous cell proliferation induced by pregnancy-associated hormonal changes. However, recent studies suggest that the remodeling of cellular microenvironment and extracellular matrix during pregnancy and involution may contribute to enhanced invasive and metastatic potential of breast carcinomas. 相似文献
25.
Meriem Haloua Nizar El Bouardi Mohamed Hbibi Badre Eddine Alami Youssef Alaoui Lamrani Mustapha Maaroufi Meryeme Boubbou 《Radiology Case Reports》2022,17(9):3015
Primary intracranial germ cell tumors are rare, often affecting children and young patients. Germinomas are the most common type of germ cell tumors. We present the case of a 10-year-old child, who was admitted with decreased visual acuity, asthenia, polyuro-polydipsic syndrome, and gait disorder. His biological assessment showed an hypocortisolemia and diabetes insipidus. Imaging found a bifocal process in the suprasellar and pineal region, suggestive of a bifocal germinoma. Imaging data and the positivity of human chorionic gonadotrophin in the cerebrospinal fluid were in favor of the diagnosis of bifocal germinal tumor confirmed by biopsy. Currently the patient is hospitalized in pediatric oncology department.The diagnosis of germ cell tumors is based on imaging, tumor marker assays, and biopsy. They are treated by radiation therapy alone or in combination with reduction chemotherapy, and surgery for tumor residues. The location of the tumor usually makes surgery difficult. 相似文献
26.
Sara Azzabi Zouraq Meryem Haloua Badr Alami Moulay Youssef Alaoui Lamrani Mustapha Maaroufi Meryem Boubbou 《Radiology Case Reports》2022,17(7):2342
Pheochromocytomas arising from outside the adrenal glands are called paragangliomas and constitute a rare disease and can occur in the pelvic retroperitoneum. Symptoms of excess catecholamine production, as well as elevated urine vanillylmandelic acid levels and serum and urine norepinephrine levels, are highly diagnostic for paraganglioma. Imaging can be helpful for the diagnostic of these pelvic tumors, differentiating them from other pelvic masses. We hereby present a case of pelvic malignant paraganglioma. 相似文献
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29.
Previous studies have suggested a trait-like association between neighborhood deprivation and alcohol consumption. However, it is not known whether temporarily manipulating poverty and affluence states by exposure to stimuli signifying resource-scarcity or resource-wealth would influence alcohol-seeking behavior. Here, we aimed to investigate whether implicit exposure to affluence and poverty-related pictures would influence beer consumption. Participants in a “poverty” group viewed pictures depicting impoverished environments, and participants in an “affluence” group viewed images of wealthy environments. After priming, participants were provided with nonalcoholic beer (which they were told was alcohol-containing beer) and orange juice under the guise of a bogus taste test, to measure their alcohol-seeking behavior. Results showed that priming participants with a resource-scarce environment led to an increase in beer consumption (as a percentage of total fluid consumed), compared to priming with a resource-rich environment. The same pattern of results was obtained in both a Western European sample (Experiment 1) and a West Indian sample (Experiment 2). In Experiment 2, we also tested whether risk-taking behavior, measured by the Balloon Analogue Risk Task, was influenced by the environmental priming; no differences between groups were observed. These results provide the first experimental evidence that manipulation of poverty-affluence state, by brief exposure to pictures of impoverished or wealthy neighborhoods, can influence alcohol-seeking behavior in adult social drinkers. 相似文献
30.
This review presents a comprehensive picture of the zoonotic parasitic diseases in Egypt, with particular reference to their relative prevalence among humans, animal reservoirs of infection, and sources of human infection. A review of the available literature indicates that many parasitic zoonoses are endemic in Egypt. Intestinal infections of parasitic zoonoses are widespread and are the leading cause of diarrhea, particularly among children and residents of rural areas. Some parasitic zoonoses are confined to specific geographic areas in Egypt, such as cutaneous leishmaniasis and zoonotic babesiosis in the Sinai. Other areas have a past history of a certain parasitic zoonoses, such as visceral leishmaniasis in the El-Agamy area in Alexandria. As a result of the implementation of control programs, a marked decrease in the prevalence of other zoonoses, such as schistosomiasis and fascioliasis has been observed. Animal reservoirs of parasitic zoonoses have been identified in Egypt, especially in rodents, stray dogs and cats, as well as vectors, typically mosquitoes and ticks, which constitute potential risks for disease transmission. Prevention and control programs against sources and reservoirs of zoonoses should be planned by public health and veterinary officers based on reliable information from systematic surveillance. 相似文献