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With the development of urban underground space and increased infrastructure functions, both the scale of engineering construction and engineering difficulties have increased globally. In the construction of structures in soft strata, especially in coastal areas, the limited bearing capacity of the foundations poses a significant challenge. The composite pile technologies employing an organic combination of the rigid pile andthe flexible column can enable efficient soft ground treatment. In light of prominent global environmental issues, low-carbon energy-saving curing technologies have been rapidly developed for application in geotechnical engineering. This paper discusses progress in research on the mechanical properties of the efficient and low-carbon pile technologies, including the stiffened deep mixing (SDM) column, squeezed branch pile, pre-bored grouting plated nodular (PGPN) pile, precast cement pile reinforced by cemented soil with a variable section (PCCV), and carbonized composite pile (CCP). In addition, it reviews the technical characteristics and recent progress of feasible low-carbon energy-efficient curing technologies. The paper also proposes future directions for theoretical research and technological development of low-carbon pile technologies. The key contribution of this review is to provide insights into efficient and low-carbon pile technologies. In addition, the findings from the study of the pile technologies used in extra-thick soft strata also provide industry practitioners with a comprehensive guide regarding the specific applications and mechanical performance of the pile technologies, which can serve as a stepping stone to facilitate the technological development of the underground space industry. [ABSTRACT FROM AUTHOR]

Rejuvenating the reclaimed asphalt pavement by crumb rubber modified binder for recycling in new pavements arouses a great interest as a sustainable paving technology that uses waste to recycle waste and hinders resource depletion. By investigating rheological and adhesion/cohesion characteristics of the asphalt binder, this study aims to divine optimal dosages of reclaimed asphalt and crumb rubber that enhance the overall performance of the binder without undermining any feature. Thirty binders produced from two types of virgin binder, two sources of reclaimed asphalt, three dosages of reclaimed asphalt, and two dosages of crumb rubber were prepared and tested. Bonding, rheological, and physiochemical characteristics of binders were investigated using pull-off test, dynamic shear rheometer, and Fourier transformed infrared spectroscopy. The results show that mixing reclaimed asphalt with rubberized asphalt greatly enhances the cohesion strength, rutting resistance, creep resistance, and colloid homogeneity. However, certain reclaimed asphalt and crumb rubber dosages undermine the fatigue cracking resistance. The physiochemical investigation revealed that the crumb rubber chains intensively swell and disintegrate simultaneously during mixing with virgin binder and further mixing with reclaimed asphalt. Through correlation analysis, it was emphasized that the improvement of cohesion strength and rheological characteristics is ascribed to the physiochemical changes caused by crumb rubber interaction and reclaimed asphalt addition. [Display omitted] [ABSTRACT FROM AUTHOR]

Gastrointestinal stromal tumors (GISTs) are mesenchymal tumors that mainly arise in the gastrointestinal tract. They are usually asymptomatic and are incidentally discovered during endoscopy or surgery. Diagnosis is confirmed by histological examination of the specimen. This is the case report of an asymptomatic GIST of the small intestine diagnosed by wireless capsule endoscopy. The tumor was initially suspected to be a leiomyoma, as GISTs in young adults are rare and are mainly discovered incidentally during colorectal cancer screening. The patient was a 35-year-old woman with occult gastrointestinal bleeding, with a normal medical history. An endoscopic assessment of the upper and lower GI tract (gastroscopy and colonoscopy) was performed, but did not reveal any abnormalities. Subsequently, an exophytic tumor initially suspected as leiomyoma or external pressure was detected in the small intestine by capsule endoscopy. A computed tomography scan was suggestive of a soft tissue tumor arising from the small intestine. A surgical specimen was obtained and the immunohistochemical examination revealed that the tumor was positive for CD117 and discovered on GIST-1 markers, while the markers of carcinoma, melanoma and lymphoma were negative, which was consistent with a diagnosis of a low-risk GIST with a mitotic count of <5/50 high-power fields. In this study, we aimed to present in detail the capsule endoscopic and radiological characteristics, as well as the findings of the histological examination of the surgical specimen. In conclusion, when occult blood is detected in the stool, even when gastroscopy and colonoscopy reveal no abnormal findings, small intestinal lesions should be suspected. Exophytic small intestinal GISTs, although rare, particularly in younger patients, they should be considered by physicians in the differential diagnosis of obscure GI bleeding of unknown origin, in order to reduce morbidity and mortality. Capsule endoscopy may be considered to be the first choice as a diagnostic tool for obscure GI bleeding.