Study on Pricing Model of Air Freight Based on Revenue Management

At present, the air freight rate does not match with the current competitive environment, and the revenue level of air freight is not ideal. How to improve the level of income management and balance the relationship between quantity and price has become an urgent problem for China’s air freight. In this context, this paper constructs an air freight pricing model based on revenue management. We review the application models of the air freight, and select the parameters for pricing model. Then the pricing model is constructed based on the revenue management and the status quo of China’s air freight industry. Finally, the model is tested by simulation analysis. This paper aims to provide a scientific and reasonable decision-making reference for air freight pricing through the improvement of pricing model

A comment on "Ab initio calculations of pressure-dependence of high-order elastic constants using finite deformations approach" by I. Mosyagin, A.V. Lugovskoy, O.M. Krasilnikov, Yu.Kh. Vekilov, S.I. Simak and I.A. Abrikosov

Recently, I. Mosyagin, A.V. Lugovskoy, O.M. Krasilnikov, Yu.Kh. Vekilov, S.I. Simak and I.A. Abrikosov in the paper: "Ab initio calculations of pressure-dependence of high-order elastic constants using finite deformations approach"[Computer Physics Communications 220 (2017) 2030] presented a description of a technique for ab initio calculations of the pressure dependence of second- and third-order elastic constants. Unfortunately, the work contains serious and fundamental flaws in the field of finite-deformation solid mechanics.Comment: 3 pages, 0 figure

Trefoil Factor 3, Cholinesterase and Homocysteine: Potential Predictors for Parkinson\u27s Disease Dementia and Vascular Parkinsonism Dementia in Advanced Stage

Trefoil factor 3 (TFF3), cholinesterase activity (ChE activity) and homocysteine (Hcy) play critical roles in modulating recognition, learning and memory in neurodegenerative diseases, such as Parkinson\u27s disease dementia (PDD) and vascular parkinsonism with dementia (VPD). However, whether they can be used as reliable predictors to evaluate the severity and progression of PDD and VPD remains largely unknown. METHODS: We performed a cross-sectional study that included 92 patients with PDD, 82 patients with VPD and 80 healthy controls. Serum levels of TFF3, ChE activity and Hcy were measured. Several scales were used to rate the severity of PDD and VPD. Receivers operating characteristic (ROC) curves were applied to map the diagnostic accuracy of PDD and VPD patients compared to healthy subjects. RESULTS: Compared with healthy subjects, the serum levels of TFF3 and ChE activity were lower, while Hcy was higher in the PDD and VPD patients. These findings were especially prominent in male patients. The three biomarkers displayed differences between PDD and VPD sub-groups based on genders and UPDRS (III) scores\u27 distribution. Interestingly, these increased serum Hcy levels were significantly and inversely correlated with decreased TFF3/ChE activity levels. There were significant correlations between TFF3/ChE activity/Hcy levels and PDD/VPD severities, including motor dysfunction, declining cognition and mood/gastrointestinal symptoms. Additionally, ROC curves for the combination of TFF3, ChE activity and Hcy showed potential diagnostic value in discriminating PDD and VPD patients from healthy controls. CONCLUSIONS: Our findings suggest that serum TFF3, ChE activity and Hcy levels may underlie the pathophysiological mechanisms of PDD and VPD. As the race to find biomarkers or predictors for these diseases intensifies, a better understanding of the roles of TFF3, ChE activity and Hcy may yield insights into the pathogenesis of PDD and VPD

Process, microstructure and mechanical properties

Funding Information: This work was supported by National Natural Science Foundation of China (Grant No. 51875168/52002112 ), Natural Science Foundation of Hebei Province (Grant No. E2019208089 ) and “Three-Three-Three Talent Project” Foundation of Hebei Province ( C20221022 ). Sichuan Province Science Funding for Distinguished Young Scholars ( 3NSFJQ0064 ). JPO acknowledges funding by national funds from FCT – Fundação para a Ciência e a Tecnologia, I.P., in the scope of the projects LA/P/0037/2020. Science and Technology Research Project of Colleges and Universities in Hebei Province (Grant No. BJK2022020 ). Publisher Copyright: © 2023 The AuthorsAiming to decouple the inherent relationship between mass transfer and heat transfer in traditional arc-based directed energy deposition, a novel heterogeneous multi-wire indirect arc directed energy deposition (DED) has been developed for in-situ synthesis of Al-Zn-Mg-Cu alloy components. Multi-wires (Al-Cu and Al-Mg) with a bypassing Zn wire have been used to replace the traditional homogeneous twin-wires. The process, microstructure and mechanical properties of the deposited Al-Zn-Mg-Cu alloy components obtained by multi-wire indirect arc DED were investigated. The results indicate that the wire feeding speed, current and angle between the two wires have a significant influence on the multi-wire indirect arc DED process. When the current was 200 A, the different wire feeding speeds could be used for both wires and the angle between them was 90°. The resulting indirect arc presented a ‘heart’ shape and allowed to obtain an Al-5.7Zn-3.4Mg-1.6Cu (wt%) alloy with a high deposition rate of 5.1 kg/h. The Al-5.7Zn-3.4Mg-1.6Cu alloy is mainly composed of α-Al, S (Al2CuMg), η (Mg (Al, Zn, Cu)2) and η′ phases. The composition and phases are in accordance with the 7xxx series aluminum alloys. The microstructure is dominated by columnar and equiaxed grains, and it has obvious periodic distribution along the building direction, which is related to the process thermal cycle. Fine second phases η′ are observed to precipitate during the manufacturing process. Furthermore, the average hardness, ultimate tensile strength and elongation of the fabricated material are 98.6 HV, 243.9 MPa and 5.9%, respectively. These mechanical properties are higher than those of as-cast 7050 aluminum alloy, thus showing the potential of this new process variant to fabricate high strength Al alloys in the as-deposited state. The fracture morphology exhibit features mainly associated to a ductile-like fracture, accompanied by some transgranular and partial cleavage fracture characteristics. This novel multi-wire indirect arc DED provides a new choice for arc-based directed energy deposition of Al-Zn-Mg-Cu alloys and shows great potential for the in-situ synthesis of other high-performance alloys.publishersversionpublishe

Case report and brief literature review: possible association of secukinumab with Guillain–Barré syndrome in psoriasis

The etiology of Guillain–Barré syndrome (GBS) may be autoimmune. About two-thirds of patients typically experience their first symptoms within 5 days to 3 weeks after common infectious diseases, surgery, or vaccination. Infection is a triggering factor for over 50% of patients. In recent years, a growing number of studies have indicated that some immune checkpoint inhibitors and COVID-19 may also contribute to the occurrence of GBS. However, drugs are considered a rare cause of GBS. The patient in our case was a 70-year-old man who developed GBS after initiating secukinumab for psoriasis. Upon diagnosis suggesting a potential association between secukinumab and the development of GBS, as per the Naranjo adverse drug reaction (ADR) probability scale, we decided to discontinue the drug. Following this intervention, along with the administration of immunoglobulin, the patient exhibited a significant improvement in extremity weakness. The association of GBS with secukinumab treatment, as observed in this case, appears to be uncommon. The underlying mechanisms that may link secukinumab to the development of GBS are not yet fully understood and warrant further scientific inquiry and rigorous investigation. However, we hope that this report can raise greater awareness and vigilance among medical professionals to enhance the safety of patients’ medication

Myeloid cells, BAFF, and IFN-γ establish an inflammatory loop that exacerbates autoimmunity in Lyn-deficient mice

Autoimmunity is traditionally attributed to altered lymphoid cell selection and/or tolerance, whereas the contribution of innate immune cells is less well understood. Autoimmunity is also associated with increased levels of B cell–activating factor of the TNF family (BAFF; also known as B lymphocyte stimulator), a cytokine that promotes survival of self-reactive B cell clones. We describe an important role for myeloid cells in autoimmune disease progression. Using Lyn-deficient mice, we show that overproduction of BAFF by hyperactive myeloid cells contributes to inflammation and autoimmunity in part by acting directly on T cells to induce the release of IFN-γ. Genetic deletion of IFN-γ or reduction of BAFF activity, achieved by either reducing myeloid cell hyperproduction or by treating with an anti-BAFF monoclonal antibody, reduced disease development in lyn−/− mice. The increased production of IFN-γ in lyn−/− mice feeds back on the myeloid cells to further stimulate BAFF release. Expression of BAFF receptor on T cells was required for their full activation and IFN-γ release. Overall, our data suggest that the reciprocal production of BAFF and IFN-γ establishes an inflammatory loop between myeloid cells and T cells that exacerbates autoimmunity in this model. Our findings uncover an important pathological role of BAFF in autoimmune disorders

Emissions of nitrogen-based fuel combustion in swirl burner

To provide a first insight into combustion characteristics of ammonia-based fuel in gas turbine engines for power generation, a generic swirl burner is tested with ammonia/hydrogen mixtures in this study. Based on the Computational Fluid Dynamics (CFD) simulation results, Chemical Reaction Network (CRN) model is developed to study the NOx emission characteristics of different ammonia/hydrogen mixtures in a gas turbine swirl burner. The NOx emission results predicted by the CRN model using Konnov’s mechanism have shown satisfactory agreement with the experimental data. The parameter study are then performed to estimate the effect of pressure, inlet temperature and equivalence ratio. Areas are identified which more attention for model development and emission need control in future studies

Detecting and phenotyping of aneuploid circulating tumor cells in patients with various malignancies

Circulating tumor cells (CTCs) have been exclusively studied and served to assess the clinical outcomes of treatments and progression of cancer. Most CTC data have mainly been derived from distinct cohorts or selected tumor types. In the present study, a total of 594 blood samples from 479 cases with 19 different carcinomas and 30 healthy samples were collected and analyzed by Subtraction enrichment method combined with immunostaining-fluorescence in situ hybridization (iFISH). Non-hematopoietic cells with aneuploid chromosome 8 (more than 2 copies) were regarded as positive CTCs. The results showed that none of CTCs was found in all 30 healthy samples. The overall positive rate of CTCs was 89.0% in diagnosed cancer patients (ranging from 75.0% to 100.0%). Average number of 11, 5, 8 and 4 CTCs per 7.5 mL was observed in lung cancer, liver cancer, renal cancer and colorectal cancer, respectively. Among 19 different carcinomas, the total number of CTCs, tetraploid chromosome 8, polyploid chromosome 8, CTM (Circulating tumor microemboli) and large CTCs in patients with stage Ⅲ and Ⅳ were statistically higher than patients with stage Ⅰ and Ⅱ (P < 0.05). Furthermore, EpCAM expression was more frequently found in most CTCs than vimentin expression, confirming that these CTCs were of epithelial origin. In addition, small and large CTCs were also classified, and the expression of vimentin was mostly observed in small CTCs and CTM. Our results revealed that there are higher numbers of CTCs, tetraploid, polyploid and large CTCs in patients with stage Ⅲ and Ⅳ, indicating that the quantification of chromosome ploidy performed by SE-iFISH for CTCs might be a useful tool to predict and evaluate therapeutic efficacy as well as to monitoring disease progression