Analytical solution for longitudinal deformation of shield tunnel induced by overcrossing tunnelling considering circumferential joints

This paper presents a new analytical solution for assessing the longitudinal deformation of shield tunnel associated with overcrossing tunnelling in consideration of circumferential joints.A simplified longitudinal beam-spring model(SLBSM)is established to model the longitudinal behaviours of shield tunnel,which can consider the opening and dislocation between segmental rings simultaneously.Then,the existing tunnel is treated as the SLBSM resting on the elastic foundation.The state equations including tunnel displacements and internal forces are constructed to solve the discontinuous deformation of circumferential joint-segmental ring.The feasibility of the proposed solution is verified through three well-documented cases.The predictions from the proposed method are also compared with other analytical methods.It is found that the proposed method can well capture the deformation of tunnel segmental rings and joints,where the rigid displacement mainly occurs in the segmental rings while the rotation and dislocation occur in the circumferential joints.Some dominant parameters are also analysed to explore the effects on existing tunnel deformation,including the rotation stiffness and shearing stiffness of joints,the skew angle and the clearance between new and old tunnels.

Net energy of corn,soybean meal and rapeseed meal in growing pigs

Background: Two experiments were conducted to estimate the net energy(NE) of corn, soybean meal, expel er-pressed rapeseed meal(EP-RSM) and solvent-extracted rapeseed meal(SE-RSM) using indirect calorimetry and to validate the NE of these four ingredients using pig growth performance.Methods: In Exp.1, 24 barrows(initial BW = 36.4 ± 1.6 kg) were allotted to 1 of 4 diets which included a corn basal diet,a corn-soybean meal basal diet and two rapeseed meal diets containing 20% EP-RSM(9.5% ether extract) or SE-RSM(1.1% ether extract) substituted for corn and soybean meal. The design allowed the calculation of NE values of corn,soybean meal and rapeseed meals according to the difference method. In Exp.2, 175 growing pigs(initial BW = 36.0± 5.2 kg) were fed 1 of 5 diets for 28 d, with five pigs per pen and seven replications(pens) per treatment in order to validate the measured energy values. Diets were a corn-soybean meal diet and four diets including 10% or 20% EP-RSM and 10% or 20% SE-RSM.Results: The NE of corn, soybean meal, EP-RSM and SE-RSM were 12.46, 11.34, 11.71 and 8.83 MJ/kg DM, respectively. The NE to ME ratio of corn(78%) was similar to tabular values, however, the NE to ME ratios of soybean meal(70%) and rapeseed meal(76%) were greater than tabular values. The greater NE value in EP-RSM than in SE-RSM is consistent with its higher EE content. Increasing EP-RSM or SE-RSM did not affect the growth performance of pigs and the caloric efficiency of NE was comparable for al diets.Conclusions: The NE of EP-RSM was similar to soybean meal, and both were greater than SE-RSM. The DE, ME and NE values measured in Exp.1 are confirmed by results of Exp. 2 with comparable caloric efficiencies of DE, ME or NE for all diets.

Methodologies on estimating the energy requirements for maintenance and determining the net energy contents of feed ingredients in swine:a review of recent work

In the past two decades, a considerable amount of research has focused on the determination of the digestible(DE) and metabolizable energy(ME) contents of feed ingredients fed to swine. Compared with the DE and ME systems, the net energy(NE) system is assumed to be the most accurate estimate of the energy actually available to the animal. However, published data pertaining to the measured NE content of ingredients fed to growing pigs are limited. Therefore, the Feed Data Group at the Ministry of Agricultural Feed Industry Centre(MAFIC) located at China Agricultural University has evaluated the NE content of many ingredients using indirect calorimetry. The present review summarizes the NE research works conducted at MAFIC and compares these results with those from other research groups on methodological aspect. These research projects mainly focus on estimating the energy requirements for maintenance and its impact on the determination, prediction, and validation of the NE content of several ingredients fed to swine. The estimation of maintenance energy is affected by methodology, growth stage,and previous feeding level. The fasting heat production method and the curvilinear regression method were used in MAFIC to estimate the NE requirement for maintenance. The NE contents of different feedstuffs were determined using indirect calorimetry through standard experimental procedure in MAFIC. Previously generated NE equations can also be used to predict NE in situations where calorimeters are not available. Although popular, the caloric efficiency is not a generally accepted method to validate the energy content of individual feedstuffs. In the future,more accurate and dynamic NE prediction equations aiming at specific ingredients should be established, and more practical validation approaches need to be developed.

Concerns about the misleading conclusions regarding estimation of the net energy value of soybean meal relative to corn using the caloric efficiency approach in pigs

Apart from energy balance trials such as calorimetry,growth trials could also be used to estimate the energy values of feed ingredients with caloric efficiency as an indicator.Recent work used such methods reported greater net energy(NE)value of soybean meal(SBM)relative to corn in nursery pigs.We theoretically compared the NE values of SBM and corn according to the definition of NE and properties of the major chemical compositions in each ingredient.Meanwhile,we thoroughly examined the diet formulations and related analysis used in this work and compared this study with some peer works.We found that this study may suffer from problems with experimental design,reference citation,and data interpretation.In summary,the conclusion from the recent work that the SBM NE value may be greater than the corn NE value is likely to be erroneous.

Analysis of efficacy and safety for the combination of regorafenib and PD-1 inhibitor in advanced hepatocellular carcinoma:A real-world clinical study

Background and aims:Hepatocellular carcinoma(HCC)is a prevalent and deadly disease with limited treatment options.Regorafenib,a tyrosine kinase inhibitor,has shown promise in HCC treatment but faces limitations as a monotherapy.Combining regorafenib with PD-1 inhibitor may improve efficacy and survival outcomes for patients.This retrospective analysis was conducted to explore its efficacy and safety,providing reference experience for better application of this combination therapy.Methods:This retrospective single-center study evaluated the efficacy and safety of combining regorafenib with PD-1 blockade for patients with HCC.Efficacy was evaluated according to the RECIST 1.1 evaluation criteria.Safety was assessed using CTCAE 4.0.Data was analyzed to compare survival status in different subgroups.Results:Generally,there were 76 patients with HCC elected to receive the regorafenib plus PD-1 blockade treatment during the study period.The objective response rate was 21.1%(n?16),and the disease control rate was 56.6%(n?43).Median progression-free survival(PFS)was 6.8 months,and median overall survival had not yet been reached.All patients suffered of at least 1 adverse event.Grade3 adverse events occurred in 31.6%of patients(n?24),with the most common being hand-foot syndrome,decreased appetite,and abdominal distension.Subgroup analyses showed no significant differences in PFS based on cirrhosis status or previous treatment lines.Conclusion:With manageable safety,regorafenib combined PD-1 inhibitor could bring survival benefits for advanced HCC who have received systemic treatment.Further,the Cox analysis showed that HBV infection,metastasis,etc.did not have significant effects on the survival benefits.