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In other words, although soil mineralogy may well play a key role in the varying strength of clays with the water content, I c i SB u(FC) sb mobilised at the FC liquid-limit water content does not respond in any significant way to soil mineralogy; the same conclusion has been previously reported by O'Kelly I et al i . ([16]) employed a Geonor G-200 model 60°-60 g FC device to determine the apparent variations of I c i SB u(FC) sb with the water content about the I w i SB L-FC(BSI) sb (established using the 30°-80 g FC device) for the various fine-grained soils investigated. Keywords: Liquid limit; fall-cone; cone factor; undrained strength; fine-grained soil EN Liquid limit fall-cone cone factor undrained strength fine-grained soil 170 174 5 04/04/23 20230301 NES 230301 It is the authors' opinion that confusion could arise from the analyses and explanations of the experimental fall-cone (FC) results presented in the paper by Nagaraj I et al i . Figure 1(a): An x:y scatter plot showing the changes in undrained shear strength at the British Standard fall-cone liquid-limit water content against the British Standard fall-cone liquid-limit water content for six different fine-grained soils investigated by Nagaraj et al. (2018). [Extracted from the article]

This study investigated the cyclic behaviour of a severe dilative silica sand from Rudsar, Northern Iran, through simple shear tests. For this purpose, monotonic (constant volume/vertical stress) and cyclic (constant vertical stress) tests were performed on moist sand specimens prepared at initial relative densities of 20–60%, vertical stresses of 100–300 kPa, and cyclic stress ratios of CSR = 0.20, 0.25 and 0.30. These also included bender element tests to determine the small-strain shear modulus Gmax. An increase in initial relative density, vertical stress and number of loading cycles led to a nonlinear increase in the secant shear modulus Gsec, while the opposite was observed for increasing CSR. Moreover, increasing CSR improved the damping ratio, whereas increasing the initial relative density, vertical stress and/or number of loading cycles had negative effects on the damping ratio. Finally, the bender element test results showed that Gmax increased for increasing vertical stress and initial relative density. [ABSTRACT FROM AUTHOR]

This short communication presents some comments on the Journal of Natural Fibers paper titled "Strength and Deformation Behavior of Fine-Grained Soils Reinforced with Hair Fibers and Its Application in Pavement Design." The paper demonstrated the significant improvements in undrained shear strength and stiffness, and CBR value achieved for addition (at 2 wt%) of waste human-hair-fiber (HHF) to Dhanauri Clay and Delhi Silt materials investigated. Considering the proposed application in soil improvement, the paper also examined rigid and flexible pavement design for HHF-reinforced soil subgrade. Various aspects of the original investigation are commented on in this communication, including (i) the apparent poorer compaction behavior (and hence the likely higher compressibility) of the HHF-reinforced soil materials compared to their unreinforced counterparts and (ii) a technical error in the reported consistency/Atterberg limits experimental investigation. Consistency limits testing is synonymous with the soil fraction passing the 425-μm sieve size, such that it is not proper to perform consistency limits testing for HHF-reinforced fine-grained soil samples. The commentary concludes with some recommendations for future studies on soil−HHF mixtures directed at investigating their long-term geotechnical performance as soil subgrade. [ABSTRACT FROM AUTHOR]

Experiencing early-life adversity plays a key role in the development of mood disorders in adulthood. Experiencing adversities during early life period negatively affects brain development. Sex steroids such as progesterone affect the brain structure and functions and subsequently affects behaviour. We assess the antidepressant-like effect of progesterone in a mouse model of maternal separation (MS) stress, focussing on its anti-neuroinflammatory and antioxidative effects. NMRI mice were treated with progesterone (10, 50, and 100 mg/kg, i.p., respectively) for 14 days. Valid behavioural tests including forced swimming test (FST), splash test and open field test (OFT) were used. Quantitative reverse transcription-PCR (qRT-PCR) was used for evaluation of genetic expression in the hippocampus. Antioxidant capacity was assessed by the FRAP method and the level of malondialdehide by TBA. MS provoked depressive-like behaviour in mice. Treatment of MS mice with progesterone increased the grooming activity time in the splash test and decreased the immobility time in the FST. In addition, progesterone decreased the expression of inflammatory genes related to neuroinflammation (IL-1β, TNF-α, TLR4 and NLRP3) as well as increased the antioxidant capacity and decreased the lipid peroxidation (MDA) in the hippocampus. Administration of progesterone significantly mitigated the negative effects of MS on behaviours relevant to depressive-like behaviour as well as attenuated neuro-immune response and oxidative stress in the hippocampus of MS mice. In this context, we conclude that progesterone, at least partially, via attenuation of oxidative stress and neuroinflammation, exerts antidepressant-like effects. [ABSTRACT FROM AUTHOR]

This study aims at establishing a universal predictive model for the unconfined compressive strength (UCS) of artificially cemented fine-grained soils. Model development, its validation and calibration were carried out using a comprehensive database gathered from the research literature. The dimensional analysis concept was successfully extended to the soil–cement UCS problem, thereby leading to a practical dimensional model capable of simulating the UCS as a function of the blend's index properties — that is, cement content, specific surface area, curing time, and the compaction state parameters (including water content and dry density). The predictive capability of the proposed model was examined and further validated using routine statistical tests, as well as conventional fit-measure indices which resulted in R2 > 0.95 and NRMSE < 5%. A sensitivity analysis was also carried out to quantify the relative impacts of cement content, curing time and soil plasticity on the UCS. The higher the soil plasticity, the higher the positive sensitivity to cement content, implying that soils of higher plasticity would require higher cement contents for stabilization. On the contrary, the higher the soil plasticity, the lower the positive sensitivity to curing time, indicating a more effective cement hydration in soils of lower plasticity. Finally, an explicit calibration procedure, involving a total of three UCS measurements for three recommended soil–cement mix designs, was proposed and validated, thus allowing for the proposed model to be implemented with confidence for predictive purposes, preliminary design assessments and/or soil–cement optimization studies. [ABSTRACT FROM AUTHOR]

Background and objectives: With regard to their ease of harvest and common developmental origin, dental pulp stem cells (DPSCs) may act as a favorable source of stem cells in generation of nerves. Moreover; cellular migration and differentiation as well as survival, self-renewal, and proliferation of neuroprogenitor species require the presence of the central nervous system (CNS) mitogens including EGF and bFGF. Accordingly, the possibility of the induction of neuronal differentiation of DPSCs by EGF and bFGF was evaluated in the present study. Materials and methods: DPSCs were treated with 20 ng/ml EGF, 20 ng/ml bFGF, and 10 µg/ml heparin. In order to further induce the neuroprogenitor differentiation, DPSC-derived spheres were also incubated in serum-free media for three days. The resulting spheres were then cultured in high-glucose Dulbecco's Modified Eagle Medium (DMEM) with 10% FBS. The morphology of the cells and the expression of the differentiation markers were correspondingly analyzed by quantitative polymerase chain reaction (qPCR), western blotting, and immunofluorescence (IF). Results: The EGF/bFGF-treated DPSCs showed significant increase in the expression of the neuroprogenitor markers of Nestin and SRY (sex determining region Y)-box 2 (SOX2), 72 h after treatment. The up-regulation of Nestin and SOX2 induced by growth factors was confirmed using western blotting and IF. The cultures also yielded some neuron-like cells with a significant rise in Nestin, microtubule-associated protein 2 (MAP2), and Neurogenin 1 (Ngn1) transcript levels; compared with cells maintained in the control media (p < 0.05). Conclusion: DPSCs seemed to potentially differentiate into neuron-like cells under the herein-mentioned treatment conditions. [ABSTRACT FROM AUTHOR]

The efficiency of a commercially manufactured sulphonated oil (SO) agent in treating a highly expansive soil was investigated through an extensive experimental program. A total of six SO to water mass concentrations, i.e. 0.25, 0.5, 0.75, 1, 1.25 and 2.5%, were examined. The test program included swell–load oedometer, unconfined compressive strength and cyclic wetting and drying tests. SO-stabilisation amended the soil's mechanical behaviour through improvements achieved in swelling and strength characteristics. The reduction in swelling potential and swelling pressure was dependent on SO concentration, while the effect of curing time was found to be insignificant. A similar dependency was concluded for the unconfined compressive strength and stiffness of the stabilised soil. Both dependencies suggested an SO concentration of 1.25% capable of yielding an optimal stabilisation scheme. Results of the cyclic wetting and drying tests indicated that the beneficiary effects of SO-stabilisation at optimum concentration, particularly in ameliorating the adverse effects of swell–shrink-related volume changes and to some extent increasing the strength, are strongly preserved under the influence of alternate wetting and drying. [ABSTRACT FROM AUTHOR]

The air-entry value and residual state suction are two critical variables obtained from the soil–water characteristic curve (SWCC). An accurate determination of these variables is essential for the prediction of unsaturated soil properties. Currently, these variables are obtained by a conventional graphical method, which is implemented to the fitted SWCC. The graphical method is associated with subjective uncertainty, leading to inconsistent results. This study presents a new method to determine the air-entry value and residual state suction. Explicit equations are established with respect to four common van Genuchten (vG) SWCC model classes. The relationships between the air-entry value and fitting parameters are analysed using a compiled database of varying soil textural classes. The proposed equations outperform the graphical method by avoiding subjective judgements. Finally, ANOVA and sensitivity analyses are conducted to compare the advantages of the existing model classes in determination of the air-entry value. [ABSTRACT FROM AUTHOR]

Background: Ulcerative colitis (UC) is a chronic inflammatory disorder of the large intestine histologically characterized by indistinct sustained inflammatory responses. Genetical susceptibility and environmental factors’ effects play the roles in disease occurrence and it can be life threatening if remains untreated. It seems that intensification of inflammatory responses in this condition is not restricted to a specific cell line of T lymphocytes. Our aim was to determine the number of T helper 9 (Th9) cells in inflamed colonic biopsies of UC patients. We also correlated it with interleukin (IL)-9 protein level in addition to certain genes expressions associated with Th9 phenotype. Methods: Expression of CD4 and IL-9 were evaluated by immunohistochemical staining. Enzyme linked immunosorbent assay (ELISA) was performed to determine the colonic expression of IL-9 protein and finally mRNA expressions of interferon regulatory factor 4 (Irf4), Smad2, and Smad3 were measured by real-time polymerase chain reaction (RT-PCR) as critical transcription factors of Th9 differentiation. Results: Number of Th9 cells was significantly increased in inflamed samples as compared with normal tissues. Also quantitative measurement of IL-9 by ELISA and mRNA expressions of Irf4, Smad2, and Smad3 showed notable correlative enhancements in patient’s samples. Conclusion: Function and number of Th9 cells are up-regulated in the inflamed mucosa of UC patients as with the protein secretion of IL-9 and mRNA expressions of Irf4, Smad2, and Smad3, so Th9 cells and IL-9 may become remarkable therapeutic targets for IBD treatment in the future. [ABSTRACT FROM AUTHOR]