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The cement stabilization techniques have been applied to various types of infrastructure and become one of the essential techniques. A lot of researches have been conducted on the physical and mechanical properties of the cement stabilized soils, many of which are the studies on the stabilized soil after the hydration. However, the number of researches is limited on the physical and mechanical behavior of cement stabilized soil during the hydration stage and subjected to shear deformation during the hydration stage. In this study, a series of direct shear tests was conducted on the shear behavior of cement stabilized soil to investigate the influence of the magnitude and timing of the shearing on the shear behavior. The researche revealed that the shear strength of the stabilized soil is recovered to the peak strength when it is subjected to the shear deformation prior to the peak strength and the shear strength increases by the cement hydration. On the other hand, when the soil is subjected to the large deformation exceeding to the peak strength, the shear strength loss is not recovered in the following shearing stage. The strength gain due to the cement hydration is also influenced by the initial shearing, where the strength of soil subjected to the large shearing remains small for the curing stage. In this manuscript, the test results are introduced to discuss the influence of the initial shearing as well as the testing procedure.

This paper presents Long Range Wide Area Network (LoRaWAN) scalability improvement using the Utilization Weighted (UW) spreading factor (SF) assignment algorithm that was logically designed to equalize SFs usage based on the M/D/1 queuing model. The test area containing dairy farms housing approximately 1,200 cows in Photharam district, Ratchaburi province of Thailand, was selected to simulate the proposed algorithm and evaluate its performance. The suburban Hata path loss model was chosen as a reference to incorporate the actual network environment into the simulation. It is then carefully optimized by factoring in the empirical path loss data collected in a 12-kilometer radius of the gateway location and then applying the parameters adjustment (PA) tuning method that proved to provide lower root mean square errors (RSMEs) than the RMSE tuning method. Two key performance indicators, including packet received rate (PRR) and energy consumption, were compared between the UW algorithm and the Min-airtime or traditional method. The simulation was focused on the 2-kilometer radius wherein most dairy farms reside. It was found that the UW algorithm provided higher PRR without jeopardizing the energy consumption comparing to the traditional LoRaWAN, due to the more equalization of SFs employment. The maximum improvement of PRR was around 43.90%, while the energy consumption level was maintained at approximately 113 J per day per node.

Abstract Background To report an unusual case of non-nanophthalmic uveal effusion syndrome (UES) with histologically normal sclera but responsive to scleral resection. Case presentation A73-year-old man presented with a bullous retinal detachment without ciliochoroidal detachment on funduscopic examination of the right eye. The axial length of both eyes was normal. Extensive investigations for possible causes of exudative retinal detachment were performed with unremarkable results except for choroidal hyperpermeability on indocyanine green angiography (ICGA). Ultrasound biomicroscopy (UBM) revealed scleral thickening with peripheral choroidal elevation leading to the diagnosis of UES. Partial thickness sclerectomy and sclerotomy was performed resulting in complete retinal reattachment, reduction of choroidal hyperpermeability on ICGA and improvement of visual acuity. However, histological studies of the excised sclera revealed no scleral architectural changes or abnormal deposits. Conclusions The diagnosis of UES in non-nanophthalmic eyes is challenging. Thorough systemic and ocular investigations are critical to rule out other etiologies. UBM can be helpful to evaluate scleral thickness and anterior choroid in equivocal cases. Our case was unique in that, although the sclera was thick, no abnormal microscopic scleral architecture could be identified. Misdiagnosis may lead to different surgical procedures such as vitrectomy resulting in unfavorable outcomes.

This study focuses on the role of photosensitizers in photodynamic therapy. The photosensitizers were prepared in combinations of 110/220 µM erythrosine and/or 10/20 µM demethoxy/bisdemethoxy curcumin with/without 10% (w/w) nano-titanium dioxide. Irradiation was performed with a dental blue light in the 395–480 nm wavelength range, with a power density of 3200 mW/cm2 and yield of 72 J/cm2. The production of ROS and hydroxyl radical was investigated using an electron paramagnetic resonance spectrometer for each individual photosensitizer or in photosensitizer combinations. Subsequently, a PrestoBlue® toxicity test of the gingival fibroblast cells was performed at 6 and 24 h on the eight highest ROS-generating photosensitizers containing curcumin derivatives and erythrosine 220 µM. Finally, the antifungal ability of 22 test photosensitizers, Candida albicans (ATCC 10231), were cultured in biofilm form at 37 °C for 48 h, then the colonies were counted in colony-forming units (CFU/mL) via the drop plate technique, and then the log reduction was calculated. The results showed that at 48 h the test photosensitizers could simultaneously produce both ROS types. All test photosensitizers demonstrated no toxicity on the fibroblast cells. In total, 18 test photosensitizers were able to inhibit Candida albicans similarly to nystatin. Conclusively, 20 µM bisdemethoxy curcumin + 220 µM erythrosine + 10% (w/w) nano-titanium dioxide exerted the highest inhibitory effect on Candida albicans.

The aim of this work was to synthesize zeolitic imidazolate framework-8 (ZIF-8) by an alternative method and then modify the surface properties for enhancing the CO2 adsorption performance. The ZIF-8 was synthesized by a water based synthesis method using 2-methyl imidazole (2-MeIM) as a hydrogen bond donor and quaternary ammonium salts (QAS) as a hydrogen bond acceptor. The optimal synthesis conditions were investigated by varying (i) the order of precursor mixing during the synthesis process (ii) different QAS (tetrabutyl ammonium bromide (TBAB), tetraethyl ammonium bromide (TEAB) and trimethyl phenyl ammonium bromide (TMPAB)) and (iii) the ratio between 2-MeIM and QAS. The results show that the optimal synthesis condition was using TMPAB as the hydrogen bond acceptor with the ratio between 2-MeIM and TMPAB of 8:2 and in the order of first mixing both hydrogen bond donor and acceptor before adding Zn(NO3)2⋅6H2O solution. TMPAB can provide uniform size distribution with the smallest particle sizes of ZIF-8. This can be explained by the higher hydrogen bond strength between hydrogen bond donor (2-MeIM) and hydrogen bond acceptor (TMPAB) when compared with that of the rest of two QAS. The synthesized ZIF-8 was modified by solvent-assisted ligand exchange methods. The organic linker of ZIF-8 (2-MeIM) was exchanged by 2-aminobenzimidazole (2-NH2bZIM) and 2-phenylimidazole (2-PhIM). The CO2 uptake of modified ZIF-8 was enhanced upon exchanging with 2-NH2bZIM. The increase in CO2 uptake was due to an additional interaction between CO2 and exchanged imidazole linker and an increase in surface properties (higher surface area, pore size and pore volume).