Impact of Capacity Drop on Commuting Systems under Uncertainty

This paper analyzes the impact of capacity drop on commuters’ travel choice behaviors under uncertainty. For clarity, we assume that the capacity drop is triggered by the queue forming at the bottleneck under the hypercongestion circumstances, and the stochasticity of the drop could not be neglected. Considering the uncertainty of travel time, we establish a bottleneck model with commuters choosing their departure time according to the mean travel cost. From the proposed model, analytical solutions are achieved and therefore several properties are presented, including monotonicity of travel cost and departure rate, and the relationship between dispersion degree and length of peak period. To alleviate traffic congestion at the bottleneck and avoid capacity drop, we design a time-varying toll scheme and a step toll scheme. Evolution of queue length in equilibrium is discussed based on the Laih model. Numerical examples are also presented to demonstrate the established model and the effectiveness of the proposed toll schemes. Document type: Articl

Chilling Stress—The Key Predisposing Factor for Causing Alternaria alternata Infection and Leading to Cotton (Gossypium hirsutum L.) Leaf Senescence

Leaf senescence plays a vital role in nutrient recycling and overall capacity to assimilate carbon dioxide. Cotton premature leaf senescence, often accompanied with unexpected short-term low temperature, has been occurring with an increasing frequency in many cotton-growing areas and causes serious reduction in yield and quality of cotton. The key factors for causing and promoting cotton premature leaf senescence are still unclear. In this case, the relationship between the pre-chilling stress and Alternaria alternata infection for causing cotton leaf senescence was investigated under precisely controlled laboratory conditions with four to five leaves stage cotton plants. The results showed short-term chilling stress could cause a certain degree of physiological impairment to cotton leaves, which could be recovered to normal levels in 2–4 days when the chilling stresses were removed. When these chilling stress injured leaves were further inoculated with A. alternata, the pronounced appearance and development of leaf spot disease, and eventually the pronounced symptoms of leaf senescence, occurred on these cotton leaves. The onset of cotton leaf senescence at this condition was also reflected in various physiological indexes such as irreversible increase in malondialdehyde (MDA) content and electrolyte leakage, irreversible decrease in soluble protein content and chlorophyll content, and irreversible damage in leaves' photosynthesis ability. The presented results demonstrated that chilling stress acted as the key predisposing factor for causing A. alternata infection and leading to cotton leaf senescence. It could be expected that the understanding of the key factors causing and promoting cotton leaf senescence would be helpful for taking appropriate management steps to prevent cotton premature leaf senescence

Desipramine Pretreatment Improves Sympathetic Remodeling and Ventricular Fibrillation Threshold after Myocardial Ischemia

Abnormal increase in sympathetic nerve sprouting was responsible for the ventricular arrhythmogenesis after myocardial infarction. This study investigated whether the norepinephrine transporter inhibitor, desipramine, can modulate sympathetic remodeling and ventricular fibrillation threshold (VFT) after myocardial ischemia-reperfusion. Rats were administered desipramine (0.8 mg/kg, IV) before or after myocardial ischemia. VFT, infarct size, tyrosine hydroxylase (TH) and growth-associated protein 43 (GAP43)-positive nerve fibers were measured after one week. The VFT of preischemic treatment group was 11.0±2.65 V and significantly higher than that of control ischemic group (7.2±1.30 V, P<0.05). Infarct size in the preischemic treatment group (23.3±2.4%) was significantly lower than that in the control ischemic group (30.8±1.3%, P<0.05) and the delayed application group (27.1±2.6%, P<0.05). The density of TH and GAP43-positive nerve fibers in the control ischemic group was significantly higher than that in the other three groups (P<0.05). The density of nerve fibers improved after desipramine treatment. Moreover, there was a negative correlation between the VFT and both TH and GAP43-positive nerve fiber density in the infarct border zone (P<0.05). Desipramine treatment before acute myocardial ischemia can decrease infarct size, improve sympathetic remodeling, and increase VFT and electrical stability of ischemic hearts. Desipramine appears to cause myocardial ischemic preconditioning

Simulation on mechanical and failure characteristics of sandstone with elliptical hole under tension-shear effect

Under the influence of geological environment and engineering disturbance, elliptical hole-defects exist widely in engineering rock mass. Excavation unloading causes rebound tensile stress in rock mass. The tension-shear stress zone is formed under the hole defects, which induces the tension-shear failure of rock mass and greatly reduce the stability of engineering rock mass. In order to study the mechanical properties and failure behavior of the rock mass with an elliptical hole under tension and shear, the numerical model was built using discrete element numerical simulation based on the rock mechanics test results. Furthermore, the tension-shear numerical modelling tests of rock mass with an elliptical hole of different hole inclination angle α and the ratio of long to short axis k were carried out, and the meso-mechanism of crack evolution was revealed from the point of view of stress tensor. The results show that when k is constant, with the increase of α, the shear strength approximately shows a “W” shape under low normal tensile stress (1–3 MPa), and the minimum value is obtained when α is 120° or 150°, and the maximum value is obtained when α is 90°. Under high normal tensile stress (4–6 MPa), the shear strength increases at first and then decreases, and the minimum and maximum values are obtained when α is 0° and 90°, respectively. When α is constant, for the rock mass with an elliptical hole if α is not 90°, the shear strength decreases nonlinearly with the increase of k. The sensitivity of stress concentration of the elliptical hole to normal tensile stress decreases at first and then increases with the increase of α, and the sensitivity is the highest when α is 0°. The sensitivity is the lowest when α is 90°, and the sensitivity is higher when α is 120°and 150° than that when α is 30°and 60°. The strength of the rock mass with an elliptical hole is obviously worse than that of intact rock mass, and the degree of deterioration is positively related to the normal tensile stress. The level of crack initiation stress increases with the increase of normal tensile stress, and the crack initiation angle decreases with the increase of normal tensile stress. The failure type of the rock mass with an elliptical hole under tension and shear is the tensile failure caused by anti-wing crack penetration. Under the effect of tension and shear, the maximum tensile zone is formed by the coupling of tensile stress and compressive stress in the rock mass, and the boundary near the side of the shear loading surface is the crack propagation path. The crack starts from the plastic yield at the elliptical hole. After the crack initiation, the stress is released and redistributed by the particle contact fracture, and the crack propagates along the direction of the maximum principal stress after the redistribution, which shows the nonlinear propagation mode of the crack macroscopically

Fake Alignment: Are LLMs Really Aligned Well?

The growing awareness of safety concerns in large language models (LLMs) has sparked considerable interest in the evaluation of safety within current research endeavors. This study investigates an interesting issue pertaining to the evaluation of LLMs, namely the substantial discrepancy in performance between multiple-choice questions and open-ended questions. Inspired by research on jailbreak attack patterns, we argue this is caused by mismatched generalization. That is, the LLM does not have a comprehensive understanding of the complex concept of safety. Instead, it only remembers what to answer for open-ended safety questions, which makes it unable to solve other forms of safety tests. We refer to this phenomenon as fake alignment and construct a comparative benchmark to empirically verify its existence in LLMs. Such fake alignment renders previous evaluation protocols unreliable. To address this, we introduce the Fake alIgNment Evaluation (FINE) framework and two novel metrics--Consistency Score (CS) and Consistent Safety Score (CSS), which jointly assess two complementary forms of evaluation to quantify fake alignment and obtain corrected performance estimates. Applying FINE to 14 widely-used LLMs reveals several models with purported safety are poorly aligned in practice. Our work highlights potential limitations in prevailing alignment methodologies

Tilted Fiber Bragg Grating Inscription in Boron Co-Doped Photosensitive Optical Fiber Using 266 nm Solid State Laser Pulses

peer reviewedIn the last decade, tilted fiber Bragg gratings (TFBGs) have received a lot of research attention due to their unique ability for detection of bending and surrounding refractive index (SRI). Meanwhile, fabrication of TFBGs normally requires fiber pre-hydrogenation and expensive laser systems, such as excimer laser at 193 nm or femtosecond lasers. In this work, we report the first TFBG inscriptions in Boron co-doping fibers (PS1250/1500, FIBERCORE) using low cost 266 nm solid state pulsed laser and scanning phase mask lithography technique. By using this inscription set-up, gratings with tilt angles from 2° to 10° are fabricated. Influences (pulse repetition rate and scanning speed) on the grating quality and spectral performances are discussed. Furthermore, evolution of spectra during the inscription of the 10° TFBG is illustrated showing uniform growths of both the core and cladding modes. In addition to the TFBG fabrication, temperature, bending and SRI measurement are conducted. Because the core mode is restricted to propagate in the fiber core, TFBGs could automatically provide temperature compensation. The ease of TFBG fabrication and the capability of intrinsic temperature self-compensation pave the way to their potentially promising applications in curvature and refractometric measurement

Mechanical properties and fracture damage law of coal-rock composition under the action of supercritical CO2

The injection of CO2 into deep unrecoverable coal seams is one of the effective ways to achieve CO2 geological sequestration, but CO2 will be in a supercritical state under the action of high pressure and high temperature. In order to investigate the effect of supercritical CO2 action on coal reservoir structure, based on the self-developed supercritical CO2 immersion experimental system, combined with acoustic emission test system and RFPA3D numerical simulation, we studied the three coal seam thicknesses and three top and bottom lithologies of the mechanical damage characteristics and the fracture extension evolution of “Rock-Coal-Rock” (RCR) composite specimens under the action of supercritical CO2 were investigated. The results show that: ① After the action of supercritical CO2, the degradation of compressive strength and elastic modulus of the RCR composite gradually increases and decreases with the increase of coal thickness, while the degradation of compressive strength and elastic modulus are basically the same when the strength ratios of rock and coal are different and do not show large differences; ② The action of supercritical CO2 will promote the plastic damage of the coal body and intensify the transformation of the RCR composite from tensile splitting damage to shear plastic damage, and the degree of plastic damage of RCR assemblage is positively correlated with both coal thickness and rock-to-coal strength ratio; ③ The supercritical CO2 immersion promoted the RCR assemblage to enter the elastic deformation stage earlier, and the destabilization damage occurred after a more brief elastic deformation, the greater the coal thickness, the greater the influence, while the rock-to-coal strength ratio has less influence; ④ The instability potential of RCR assemblage is proportional to coal thickness and inversely proportional to rock-coal strength ratio, and the power intensity of damage is inversely proportional to coal thickness and proportional to rock-coal strength ratio; ⑤ The total energy, dissipative energy, elastic energy and surplus energy of RCR assemblage gradually decrease with the increase of coal thickness and gradually increase with the increase of rock-coal strength ratio, and the supercritical CO2 effect will cause the elastic energy ratio of RCR assemblage specimens to decrease, the dissipative energy ratio to increase and the surplus energy ratio to decreases. Combining the above research results shows that the thicker the coal seam is, the more likely it is to be destabilized, and the higher the strength of the top and bottom rock layer is, the less likely it is to be destabilized, and the dynamic strength of the seam destabilization is inversely proportional to the coal thickness and positively proportional to the rock-to-coal strength ratio. Therefore, in a certain area of stratum that meets the premise of CO2 injection and storage, the area of stratum with higher top and bottom rock strength and thinner coal seam thickness should be selected to store CO2 with higher safety. The research results can provide some theoretical reference for the safety of geological storage of CO2 injected into deep unmineable coal seams

Transcriptome profile analysis in spinal cord injury rats with transplantation of menstrual blood-derived stem cells

IntroductionMenstrual blood-derived stem cells (MenSCs) are vital in treating many degenerative and traumatic disorders. However, the underlying molecular mechanisms remain obscure in MenSCs-treating spinal cord injury (SCI) rats.MethodsMenSCs were adopted into the injured sites of rat spinal cords at day 7 post surgery and the tissues were harvested for total RNA sequencing analysis at day 21 after surgery to investigate the expression patterns of RNAs. The differentially expressed genes (DEGs) were analyzed with volcano and heatmap plot. DEGs were sequentially analyzed by weighted gene co-expression network, functional enrichment, and competitive endogenous RNAs (ceRNA) network analysis. Next, expression of selected miRNAs, lncRNAs, circRNAs and mRNAs were validated by quantitative real-time polymerase chain reaction (qRT-PCR). Bioinformatics packages and extra databases were enrolled to scoop the genes functions and their interaction relationships.ResultsA total of 89 lncRNAs, 65 circRNAs, 120 miRNAs and 422 mRNAs were significantly upregulated and 65 lncRNAs, 72 circRNAs, 74 miRNAs, and 190 mRNAs were significantly downregulated in the MenSCs treated rats compared to SCI ones. Current investigation revealed that MenSCs treatment improve the recovery of the injured rats and the most significantly involved pathways in SCI regeneration were cell adhesion molecules, nature killer cell mediated cytotoxicity, primary immunodeficiency, chemokine signaling pathway, T cell receptor signaling pathway and B cell receptor signaling pathway. Moreover, the lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA ceRNA network of SCI was constructed. Finally, the protein-protein interaction (PPI) network was constructed using the top 100 DE mRNAs. The constructed PPI network included 47 nodes and 70 edges.DiscussionIn summary, the above results revealed the expression profile and potential functions of differentially expressed (DE) RNAs in the injured spinal cords of rats in the MenSCs-treated and SCI groups, and this study may provide new clues to understand the mechanisms of MenSCs in treating SCI

Inverse modulation of plant immune and brassinosteroid signaling pathways by the receptor-like cytoplasmic kinase BIK1

Maintaining active growth and effective immune responses is often costly for a living organism to survive. Fine-tuning the shared cross-regulators is crucial for metazoans and plants to make a trade-off between growth and immunity. The Arabidopsis regulatory receptor-like kinase BAK1 complexes with the receptor kinases FLS2 in bacterial flagellin-triggered immunity and BRI1 in brassinosteroid (BR)-mediated growth. BR homeostasis and signaling unidirectionally modulate FLS2-mediated immune responses at multiple levels. We have shown previously that BIK1, a receptor-like cytoplasmic kinase, is directly phosphorylated by BAK1 and associates with FLS2/BAK1 complex in transducing flagellin signaling. In contrast to its positive role in plant immunity, we report here that BIK1 acts as a negative regulator in BR signaling. The bik1 mutant displays various BR hypersensitive phenotypes accompanied with increased accumulation of de-phosphorylated BES1 proteins and transcriptional regulation of BZR1 and BES1 target genes. BIK1 associates with BRI1, and is released from BRI1 receptor upon BR treatment, which is reminiscent of FLS2-BIK1 complex dynamics in flagellin signaling. The ligand-induced release of BIK1 from receptor complexes is associated with BIK1 phosphorylation. However, in contrast to BAK1-dependent FLS2-BIK1 dissociation, BAK1 is dispensable for BRI1-BIK1 dissociation. Unlike FLS2 signaling which depends on BAK1 to phosphorylate BIK1, BRI1 directly phosphorylates BIK1 to transduce BR signaling. Thus, BIK1 relays the signaling in plant immunity and BR-mediated growth via distinct phosphorylation by BAK1 and BRI1, respectively. Our studies indicate that BIK1 mediates inverse functions in plant immunity and development via dynamic association with specific receptor complexes and differential phosphorylation events