Numerical Study on Water Sealing Effect of Freeze-Sealing Pipe-Roof Method Applied in Underwater Shallow-Buried Tunnel

The freezing-sealing pipe-roof method is a new presupporting technique, which fully combines the advantages of pipe-roof method and artificial ground-freezing method, and can adapt to the construction needs of underground projects in complex and sensitive strata. After the Gongbei Tunnel of Hong Kong–Zhuhai–Macao Bridge, this method will be applied for the first time in an underwater shallow-buried railroad tunnel, and there are still many urgent problems to be solved. In this article, based on the field situation and the preliminary design scheme, a convective heat transfer model under complex boundary conditions was first established. Then, the development of frozen wall thickness during the active freezing period was solved by numerical simulation for three different pipe filling modes, and the cloud map of temperature distribution in the whole section is analyzed. After that, the moving state of river water was characterized by different heat transfer coefficients, and the weakening effect of flow velocity on the top freezing wall was studied. Finally, six critical water sealing paths were selected, and the temperature differences of the frozen curtain were calculated. The results show that the mode with interval concrete filling can form a reliable frozen curtain within the scheduled time, whereas the nonfilling mode cannot achieve the water sealing requirement. River water has a large effect on the temperature at the boundary of jacking pipe and almost no effect on the center of the jacked pipe. It takes approximately 15 days from the frozen soil covering the pipe wall to reach the designed thickness, and the freezing effect of empty pipe lags approximately 28 days compared with that of solid pipe, which requires targeted enhancement measures in field projects.

The Aggressive Behaviour in Sports Among Athletes In A Public University

Collegiate athletes displayed different aggressive tendencies in an off-field situation based on the sports that they play. This study was conducted to identify the level and differences of aggressive behavior among athletes in a public university in Malaysia. A total of 91 student-athletes that represented different types of sports participated in this study. The instrument used to measure the aggressive behaviour among athletes was the Aggression Questionnaire. Descriptive statistics were used to identify the level of aggressive behaviour and the independent t-test was used to analyze the differences of aggressive behaviour based on demographic factors such as gender and types of sports. The findings revealed that the level of aggressive behaviour among athletes in the university are at a low level and there is no significant differences in aggressive behaviour based on gender and types of sports. This study contributes to the literature on the aggressive behavior in the context of student-athletes in higher education institution.

Remote ischemic preconditioning improves tissue oxygenation in a porcine model of controlled hemorrhage without fluid resuscitation

Remote ischemic preconditioning (RIPC) involves deliberate, brief interruptions of blood flow to increase the tolerance of distant critical organs to ischemia. This study tests the effects of limb RIPC in a porcine model of controlled hemorrhage without replacement therapy simulating an extreme field situation of delayed evacuation to definitive care. Twenty-eight pigs (47 ± 6 kg) were assigned to: (1) control, no procedure (n = 7); (2) HS = hemorrhagic shock (n = 13); and (3) RIPC + HS = remote ischemic preconditioning followed by hemorrhage (n = 8). The animals were observed for 7 h after bleeding without fluid replacement. Survival rate between animals of the RIPC + HS group and those of the HS group were similar (HS, 6 of 13[46%]-vs-RIPC + HS, 4 of 8[50%], p = 0.86 by Chi-square). Animals of the RIPC + HS group had faster recovery of mean arterial pressure and developed higher heart rates without complications. They also had less decrease in pH and bicarbonate, and the increase in lactate began later. Global oxygen delivery was higher, and tissue oxygen extraction ratio lower, in RIPC + HS animals. These improvements after RIPC in hemodynamic and metabolic status provide essential substrates for improved cellular response after hemorrhage and reduction of the likelihood of potentially catastrophic consequences of the accompanying ischemia.

A Novel Laboratory-Scale Mesocosm Setup to Study Methane Emission Mitigation by Sphagnum Mosses and Associated Methanotrophs

Degraded peatlands are often rewetted to prevent oxidation of the peat, which reduces CO2 emission. However, the created anoxic conditions will boost methane (CH4) production and thus emission. Here, we show that submerged Sphagnum peat mosses in rewetted-submerged peatlands can reduce CH4 emission from peatlands with 93%. We were able to mimic the field situation in the laboratory by using a novel mesocosm set-up. By combining these with 16S rRNA gene amplicon sequencing and qPCR analysis of the pmoA and mmoX genes, we showed that submerged Sphagnum mosses act as a niche for CH4 oxidizing bacteria. The tight association between Sphagnum peat mosses and methane oxidizing bacteria (MOB) significantly reduces CH4 emissions by peatlands and can be studied in more detail in the mesocosm setup developed in this study.

Assessing the Capability and Potential of LiDAR for Weed Detection

Conventional methods of uniformly spraying fields to combat weeds, requires large herbicide inputs at significant cost with impacts on the environment. More focused weed control methods such as site-specific weed management (SSWM) have become popular but require methods to identify weed locations. Advances in technology allows the potential for automated methods such as drone, but also ground-based sensors for detecting and mapping weeds. In this study, the capability of Light Detection and Ranging (LiDAR) sensors were assessed to detect and locate weeds. For this purpose, two trials were performed using artificial targets (representing weeds) at different heights and diameter to understand the detection limits of a LiDAR. The results showed the detectability of the target at different scanning distances from the LiDAR was directly influenced by the size of the target and its orientation toward the LiDAR. A third trial was performed in a wheat plot where the LiDAR was used to scan different weed species at various heights above the crop canopy, to verify the capacity of the stationary LiDAR to detect weeds in a field situation. The results showed that 100% of weeds in the wheat plot were detected by the LiDAR, based on their height differences with the crop canopy.

Remote Ischemic Preconditioning Improves Tissue Oxygenation in a Porcine Model of Controlled Hemorrhage Without Fluid Resuscitation

Purpose Remote Ischemic preconditioning (RIPC) involves deliberate, brief interruptions of blood flow to increase the tolerance of distant critical organs to ischemia. This study tests the effects of limb RIPC in a porcine model of controlled hemorrhage without replacement therapy simulating an extreme field situation of delayed evacuation to definitive care.Methods Twenty-eight pigs (47±6kg) were assigned to: (1) control, no procedure (n=7); (2) HS=hemorrhagic shock (n=13); and (3) RIPC+HS=remote ischemic preconditioning followed by hemorrhage (n=8). The animals were observed for 7 hours after bleeding without fluid replacement. Results Survival rate between animals that underwent RIPC before bleeding and those bled without prior RIPC were similar (HS, 6 of 13[46%]-vs-RIPC+HS, 4 of 8[50%], p=0.86 by Chi-square). Animals with prior RIPC had faster recovery of mean arterial pressure and developed higher heart rates without complications. Those with RIPC had less decrease in pH and bicarbonate, and the increase in lactate began later. Global oxygen delivery was higher, and tissue oxygen extraction ratio lower, in animals bled after RIPC. Conclusions These improvements after RIPC in hemodynamic and metabolic status provide essential substrates for improved cellular response after hemorrhage and reduction of the likelihood of potentially catastrophic consequences of the accompanying ischemia.

Long-term Hematopoietic Stem Cells as Sanctuary Niche during Treatment Failure in Visceral Leishmaniasis

The increasing frequency of treatment failure in visceral leishmaniasis (VL) has already resulted in discontinuation of various first-line drugs. Although most studies focus on associations with parasitic drug resistance, a knowledge gap remains about other factors determining cure versus relapse. The present study used double bioluminescent/fluorescent Leishmania infantum and L. donovani reporter lines to study relapse at the tissue and cellular level. In combination with 123 different treatments in golden Syrian hamsters, the observations provide evidence of parasites surviving in the bone marrow (BM), identifying this tissue as a sanctuary site from where the host can be recolonized. Long-term hematopoietic stem cells (LT-HSC; Lin- Sca1 + cKit + CD48- CD150+) were found to become readily infected through invasion rather than phagocytosis. Compared to other BM cells and macrophages, LT-HSCs constitute a hospitable cellular niche with low nitric oxide and reactive oxygen species levels and harbouring enormous parasite burdens. Moreover, we found that infected LT-HSCs are less sensitive to antileishmanial reference drugs in comparison to macrophages. Given the important clinical implications for the current field situation of increasing post-treatment relapse rates, this study represents an essential step by identifying the BM cellular niches responsible for Leishmania persistence and treatment failure.

Reservoir and Wellbore Flow Coupling Model for Fishbone Multilateral Wells in Bottom Water Drive Reservoirs

Nowadays, different types of complex production wells are applied in challenging reservoirs in order to maximize oil recovery. A representative application is the fishbone multilateral horizontal wells, which have advantages of expanding the drainage area information and reducing the pressure loss in the long single lateral wellbore. This paper investigated the performance of fishbone wells and derived a wellbore and reservoir flow coupling model for fishbone multilateral wells in the bottom water reservoirs. The new model considered plenty of parameters that may have significant impacts on productivity and pressure drop in the well, including the fishbone structure, the main and branch wellbores' length, the spacing distance of the branch wellbores, wellbore radius, and preformation parameters. Furthermore, a sensitivity analysis example by the numerical method presented in this paper. Compared with other models, our coupling model, when it is degraded to horizontal well, is more consistent with the results of actual field situation. In another comparative analysis, the results of the new model with branches show a good match with the numerical simulation results by software. The proposed method in this paper can be used as a valuable tool to analyze the productivity, wellbore inflow profile, and pressure profile of the fishbone multilateral wells in the bottom water reservoir.

Reproduction of contagious bovine pleuropneumonia via aerosol-based challenge with Mycoplasma mycoides subsp. mycoides

Contagious bovine pleuropneumonia (CBPP) is a respiratory disease caused by Mycoplasma mycoides subsp. mycoides. Infection occurs via Mycoplasma-containing droplets and therefore requires close contact between animals. The current infection models are suboptimal and based on intratracheal installation of mycoplasmas or in-contact infection. This work tested the infection of adult cattle via aerosols containing live mycoplasmas mimicking the infection of cattle in the field. Therefore, we infected six cattle with aerosolized Mycoplasma mycoides subsp. mycoides strain Afadé over seven consecutive days with altogether 109 colony forming units. All animals seroconverted between 11–24 days post infection and five out of six animals showed typical CBPP lesions. One animal did not show any lung lesions at necropsy, while another animal had to be euthanized at 25 days post infection because it reached endpoint criteria. Seroconversion confirmed successful infection and the spectrum of clinical and lesions observed mirrors epidemiological models and the field situation, in which only a fraction of animals suffers from acute clinical disease post infection.

Smart Culture Management: Theoretical Aspects

The aim of the research is the investigation of the essential theoretical aspects of smart culture management. The article formulates the theoretical construct of smart culture management by combining cultural management and management concepts, closely linking cultural management with the implementation of cultural policy and seeing the specifics of smart cultural management.Qualitative analysis was performed of theoretical sources of foreign countries and Lithuania. Also, a comparative analysis of different concepts was carried out, highlighting similarities and differences of concepts (in order to discern correlations between them).Five groups of cultural management concepts are distinguished: cultural management as specific management in art and culture; cultural management as a phenomenon, process reflecting the formation and implementation of cultural policy; cultural management as an institution management; cultural management as a profession and academic discipline; cultural management as leadership-based management. Theoretical analysis of the phenomenon of smartness in cultural management allowed us to distinguish six dimensions of smartness: strategic, creative development, harmonization of interests in the cultural sector, empowered cultural sector parties, the harmony of intellectual and technological capital, the culture of shared value creation.Exploring the urban cultural field situation, using a model that reflects the 6 dimensions of smart culture management and 18 qualities of a smart social system, will highlight the strengths and weaknesses of the cultural field. By analyzing the weaknesses, the researchers will be able to make recommendations on how to improve the current situation. Improving the cultural field at the local level will significantly increase the quality of cultural services provided to the population.In future research, it is planned to apply the theoretical model of smart culture management to the analysis of situation analysis in the selected city. Analysis based on this theoretical model can also be performed at the state level, thus providing a comprehensive view of the cultural field situation.