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Motivated by (continuous) facility location, we study the problem of dispersing and grouping points on a set of segments (of streets) in the plane. In the former problem, given a set of n disjoint line segments in the plane, we investigate the problem of computing a point on each of the n segments such that the minimum Euclidean distance between any two of these points is maximized. We prove that this 2D dispersion problem is NP-hard, in fact, it is NP-hard even if all the segments are parallel and are of unit length. This is in contrast to the polynomial solvability of the corresponding 1D problem by Li and Wang (2016), where the intervals are in 1D and are all disjoint. With this result, we also show that the Independent Set problem on Colored Linear Unit Disk Graph (meaning the convex hulls of points with the same color form disjoint line segments) remains NP-hard, and the parameterized version of it is in W[2]. In the latter problem, given a set of n disjoint line segments in the plane we study the problem of computing a point on each of the n segments such that the maximum Euclidean distance between any two of these points is minimized. We present a factor-1.1547 approximation algorithm which runs in O (n log ⁡ n) time. Our results can be generalized to the Manhattan distance. • A non-trivial reduction from planar rectilinear monotone 3-SAT to the 2D dispersion problem. • As a byproduct of (1), the maximum independent set problem on Colored Linear Unit Disk Graph remains NP-hard. • MIS on Colored Linear Unit Disk Graph, parameterized by the number of segments (or colors), is in W[2]. • A factor −1.1547 approximation for the 2D grouping problem. [ABSTRACT FROM AUTHOR]

In the paper "Linear time algorithm to cover and hit a set of line segments optimally by two axis-parallel squares", Theor. Comput. Sci. 769 (2019) 63–74, the LHIT problem is proposed as follows: For a given set of non-intersecting line segments L = { ℓ 1 , ℓ 2 , ... , ℓ n } in Image 1 , compute two axis-parallel congruent squares S 1 and S 2 of minimum size whose union hits all the line segments in L , and a linear time algorithm was proposed. Later it was observed that the algorithm has a bug. In this corrigendum, we corrected the algorithm. The time complexity of the corrected algorithm is O (n 2). [ABSTRACT FROM AUTHOR]

With the booming of free-floating bike-sharing systems globally, collecting target bikes effectively becomes increasingly more important in practice. Although many existing studies deal with the transportation of shared bikes with trucks, the process of manual gathering scattered target bikes along truck transportation is seldom explicitly addressed. This study tackles an integrated free-floating shared bike collection problem, which includes manually moving the target bikes to selected gathering sites and transporting the gathered bikes back to the depot with trucks. We propose a location-routing model to optimize the gathering site locations, the bike gathering assignments, and the truck delivering routes integrally under the goal of minimizing a total operation cost, and we develop a heuristic approach to solve the large-size instance of our model. A case study, which is based on the real data of Mobike company in Beijing, China, is conducted to verify the effectiveness of our planning model and solution approach and to generate managerial insights and suggestions for better practices of free-floating shared bike collection. • A location-routing model for integrated free-floating shared bike collection • Considering manual gathering during truck transportation • A hierarchical heuristic algorithm • A case study based on data from Mobike company • Cost-effective solutions and managerial insights [ABSTRACT FROM AUTHOR]

• Temperature fluctuations in thermal boundary layer are experimentally investigated over 2 × 10 10 ≲ R a ≲ 1.3 × 10 13. • The hot thermal boundary layer undergoes several transitional changes, from laminar to chaotic states. • Transitional changes of temperature fluctuations affect the mean and fluctuation temperature profiles in the hot thermal boundary layer. • For R a ≳ 7 × 10 12 , the temperature variance σ T 2 (z) in the convective mixing zone above the heated plate, follows a power-law function σ T 2 (z) ∼ z γ σ T 2 (z) ∼ z γ with γ = 2 / 3. Fluctuations of thermal boundary layer (BL) in horizontal convection (HC) strongly affect the global heat transport through the HC sample and predominately determine the flow state. Here, we present a systematic experimental study of vertical profiles of mean temperature and temperature variance in the thermal BL of a HC flow that are heated and cooled from the bottom. Three rectangular HC samples filled with de-ionised water are used in the experiment. They have the same aspect ratios Γ ≡ L : W : H = 10 : 1 : 1 but with different L (L , W and H are, respectively the length, width and height of the sample). The Rayleigh number R a varies in the range 2 × 10 10 ≲ R a ≲ 1.3 × 10 13 , and the Prandtl number P r is in the range 3.9 ≲ P r ≲ 6.5. For all R a in the studied range, we find that the cold thermal BL above the cooling plate remains laminar and the vertical profiles of measured mean temperature follow a universal scaling form predicted for laminar BL by Yan, Shishkina and He (J. Fluid Mech. , vol. 915, 2021, R5). Above the heated plate, on the contrary, temperature fluctuations in the hot thermal BL undergo several transitional changes as R a increases. For R a ≲ 6 × 10 10 , the thermal BL has a stable double-layer structure agreeing with the predicted scaling form for laminar BL and the temperature fluctuations are nearly zero. In the range 6 × 10 10 ≲ R a ≲ 1.1 × 10 11 , temperature fluctuations inside the BL have intermittent decayed oscillations, which results in deviations of the measured mean temperature profiles from the predicted scaling form. For 1.1 × 10 11 ≲ R a ≲ 10 12 , the temperature oscillations inside the BL become continuous and stable. Correspondingly, an intermediate layer emerges in the thermal BL, where the mean temperature profile has a sinusoidal variation on the distance z above the heated plate. For 10 12 ≲ R a ≲ 1.3 × 10 13 , the temperature fluctuations in the intermediate layer become irregular and intermittent, indicating a growing mixing intensity as R a increases. When R a exceeds 7 × 10 12 , the vertical distribution of mean temperature in the intermediate layer is uniform because of strong mixing. The temperature-variance vertical profiles follow a power-law function σ T 2 (z) ∼ z − γ with the exponent γ = 0.66 , which agrees with the Priestley prediction for thermal convection over a heated horizontal surface. Our results thus reveal a series of transitional changes of temperature fluctuations, from laminar to chaotic states, in the hot thermal BL. They predominately account for the enhancement of global heat transport in the HC flow observed by Reiter and Shishkina (J. Fluid Mech. , vol. 892, 2020, R1). [ABSTRACT FROM AUTHOR]

To explore the feasibility of ultra-high b-value diffusion-weighted imaging (ubDWI) in assessment of renal IRI. Thirty-five rabbits were randomized into a control group (n = 7) and a renal IRI group (n = 28). The rabbits in the renal IRI group underwent left renal artery clamping for 60 min. Rabbits underwent axial ubDWI before and at 1, 12, 24, and 48 h after IRI. Apparent diffusion coefficient (ADC st) were calculated from ubDWI with two b-values (b = 0, 1000 s/mm2). Triexponential fits were applied to calculate the pure diffusion coefficients (D), perfusion-related diffusion coefficient (D⁎), and ultra-high ADC (ADC uh). The interobserver reproducibility were evaluated. The repeated measurement analysis of variance and Spearman correlation analysis was used for statistical analysis. The ADC st , D, and ADC uh values showed good reproducibility. The ADC st , D, and D⁎ values of renal Cortex (CO) and outer medulla (OM) significantly decreased after IRI (all P < 0.05). The ADC uh values significantly increased from pre-IRI to 1 h after IRI (P < 0.05) and significantly declined at 24 h and 48 h after IRI (all P < 0.05). ADC uh was strongly positively correlated with AQP-1 in the renal CO and OM (ρ = 0.643, P < 0.001; ρ = 0.662, P < 0.001, respectively). ubDWI can be used to non-invasively evaluate early renal IRI, ADC uh may be adopted to reflect AQP-1 expression. [ABSTRACT FROM AUTHOR]

This work investigates the effect of preheating air temperature on the sooting tendency in the laminar co-flow diffusion flames of n-heptane. A modified co-flow burner was employed to produce steady n-heptane laminar diffusion flames with the preheating temperatures of co-flow air varying from 344 K to 588 K. The planar laser-induced incandescence (LII) calibrated by the line-of-sight attenuation (LOSA) was performed to quantitatively measure the soot volume fraction and the soot yield in flames and an ICCD camera was used to capture the flame luminosity images. The results reveal that the visible flame height is decreased with the preheating co-flow air temperature, and it is hardly affected by the air velocity with a constant air temperature. As the co-flow air temperature increases, the soot inception and oxidation and the peak soot concentration initiate at the lower positions in flames, and the soot loading in flames has a remarkable increasing trend by assessing the evolution of the soot volume fraction and the soot yield. However, the enhancement rate of total soot loading in flames with the co-flow air temperature below the initial fuel temperature is lower than that for the co-flow air temperature above the initial fuel temperature. In addition, the temperature sensitivity of soot loading is assessed by the maximum soot volume fraction, which is in accordance with those of the alkane in previous research. According to the response of the maximum soot yield to the co-flow air temperature and adiabatic flame temperature, the temperature sensitivity of sooting tendency in n-heptane flames is further confirmed. [ABSTRACT FROM AUTHOR]

• Soot in n-heptane flames with N 2 – and CO 2 -added oxidizers at preheat temperatures. • Laser diagnostics and numerical simulations are conducted to study soot formation. • Soot evolutions and chemical kinetics of PAH formation are uncovered. • Preheating temperature shows competition with N 2 and CO 2 dilutions on soot and PAH. To achieve low-pollutant emissions in combustion, exhaust gas recirculation is an important technology that forms lean-burn conditions by the dilution of exhaust gas (including N 2 and CO 2). This study explores the impact of N 2 and CO 2 additions to the oxidizer on soot behavior in n-heptane laminar diffusion flames under various preheating temperatures. Numerical simulations complement the investigation by examining the effect of these additions on key species for polycyclic aromatic hydrocarbon (PAH) formation at different preheating temperatures. The results indicate that N 2 and CO 2 additions have significant influences on the flame luminosity, morphology, and soot concentration distribution. Both N 2 and CO 2 dilutions restrict soot formation and oxidation, with reversals at higher preheating temperatures. While both dilutions reduce the maximum and the planar integrated soot volume fractions and the maximum soot yield, the effect is more pronounced with CO 2 due to its thermal and chemical properties. The temperature dependence of sooting tendencies varies, with N 2 showing slight changes and with CO 2 demonstrating a monotonic decrease. The production of key species is inhibited by N 2 and CO 2 addition, restricting PAH and soot formation, but higher preheating temperatures enhance key species concentrations, presenting a competitive relationship with N 2 and CO 2 dilutions. [ABSTRACT FROM AUTHOR]

In the present work, the characteristics of soot formation in laminar co-flow diffusion flames of n-heptane doped with anisole under different preheating reactant temperatures were experimentally investigated. The combined diagnostics method of the planar laser-induced incandescence (LII) and the line-of-sight attenuation (LOSA) was employed to measure the soot volume fraction and soot yield in flames under varying preheating co-flow air temperatures. Results show that preheating co-flow air leads to the enhancement of the intensity of flame luminosity, but the flame luminous intensity captured by the 410-nm filter first increases and slightly decreases with anisole content at a relatively high temperature (e.g. 573 K). The enhancement effect of preheating temperature on the peak axial soot volume fraction in n-heptane/anisole flames is weaker than that in n-heptane flames and it weakens with the anisole content, but radially-maximum soot volume fraction along the wing pathline has a different evolution with the effect of preheating temperature and anisole content. Furthermore, the evolution of the maximum soot volume fraction, the volumetrically integrated soot volume fraction and the maximum soot yield is assessed to manifest that the sooting propensity of n-heptane/anisole flames is promoted by preheating temperature due to the promotion of fuel decomposition and PAH formation. The temperature sensitivity of the sooting propensity of n-heptane/anisole flames is higher than those of n-propylbenzene and 1,2,4-trimethylbenzene flames, and it presents a non-monotonic evolution trend with anisole contents which may be attributed to the combined effect of n-heptane, anisole and nitrogen (carrier gas) on the fuel pyrolysis and the reactions of PAH formation. [ABSTRACT FROM AUTHOR]

Abstract: Recent studies suggest that GABA and glycine are protective to mature but toxic to immature cortical neurons during prolonged hypoxia. Since the action of these inhibitory amino acids is mediated by GABA and glycine receptors, the expression of these receptors is a critical factor in determining neuronal response to GABAA and glycine in hypoxia. Therefore, we asked whether in rat cortical neurons, 1) hypoxia alters the expression of the GABA and glycine receptors; 2) inhibitory amino acids change the course of GABA and glycine receptor expression; and 3) there are any differences between the immature and mature neurons. In cultured rat cortical neurons from day 4 (fourdays in vitro or DIV 4) to day 20 (DIV 20), we observed that 1) GABAARα and GlyRα1 underwent differential changes in expression during the development in vitro; 2) hypoxia for 3days decreased GABAARα and GlyRα1 density in the neurons in-between DIV 4 and DIV 20, but did not induce a major change in immature (DIV 4) and mature (DIV 20) neurons; 3) during normoxia GABA, glycine and taurine decreased GABAARα and GlyRα1 density in the immature neurons, but had a tendency to increase the density in the mature neurons, except for taurine; 4) under hypoxia, all these amino acids decreased GABAARα and GlyRα1 density in most groups of the immature neurons with a slight effect on the mature neurons; and 5) δ-opioid receptor activation with DADLE increased GABAARα and GlyRα1 density in both the immature and mature neurons under normoxia and in the mature neurons under hypoxic condition. These data suggest that inhibitory amino acids differentially regulate the expression of GABAA and glycine receptors in rat cortical neurons under normoxic and hypoxic conditions with major differences between the immature and mature neurons. [Copyright &y& Elsevier]

The present study reports a novel pattern of cytomegalic endothelial cells (CEC) in peripheral blood from a female renal transplant recipient infected with human cytomegalovirus (HCMV), which has not been reported previously. Localization of specific early antigen of HCMV, pp65 antigen, was examined by immunohistochemistry. Staining of an endothelial cell marker (CD34) was used to characterize endothelial cells. It is demonstrated that many leukocytes surrounded and adhered to a protein-like material, in which pp65-positive CEC were detected. The composition and function of this protein-like material are yet unknown. The patient lacked clinical symptoms of HCMV disease. Furthermore, similar localization patterns were found in other renal transplant recipients suffering from HCMV infections as determined by real-time PCR to detect HCMV DNA in blood. These patients showed no or only minor clinical symptoms of HCMV infection. It is suggested that these novel localization patterns of CEC may play a role in the host defense in patients infected with HCMV, but the exact relation between HCMV infection and CEC formation needs further investigation. [Copyright &y& Elsevier]

• Increasing water content is mainly helpful to improve the physical heat sink. • Water helps to inhibit carbon deposition by decreasing olefins production. • Increasing mass flow rate inhibts the cracking reaction in high temperature section. • Higher pressure has little effect on heat sink, but accelerates carbon deposition. Regenerative cooling is an effective method for heat management of hypersonic vehicles and faces a problem of insufficient cooling capacity under higher flight Mach number. Water-assisted hydrocarbon fuels thermal conversion can effectively increase heat absorption and inhibit carbon deposition. The mechanism of water on the variation of heat sink is unclear. In this study, experimental study was conducted to investigate the effect of different water contents, pressure and mass flow rates on the variation of heat sink and the distribution of gaseous products in a continuous experimental system. The results show that catalytic partial steam reforming reaction consists of catalytic steam reforming and catalytic thermal cracking in the low temperature stage (T＜490 ℃), and non-catalytic thermal cracking is activated and gradually dominate in the high temperature stage (T＞490 ℃). The contribution of water to total heat sink is mainly caused by physical heat sink. Increasing mass flow rate mainly suppress the cracking reaction in the high temperature section by reducing reaction residence time. The flow rate has little effect on the chemical reaction equilibrium. Higher pressure has little effect on heat sink, but accelerates carbon deposition by promoting the formation of olefin products. [ABSTRACT FROM AUTHOR]

To characterize capillary perfusion and tissue diffusion changes in transplant renal artery stenosis (TRAS) with diffusion-weighted imaging (DWI). We retrospectively identified 30 patients with non-contrast enhanced magnetic resonance angiography-proven TRAS. Another 20 kidney transplant recipients without TRAS were prospectively recruited to serve as control group. DWI parameters were compared among various groups with one-way analysis of variance and post hoc Tukey test. Additionally, DWI parameters were compared in 7 severe TRAS patients before and after successful angioplasty using paired Student t -test. Receiver-operating characteristic (ROC) curves were generated to evaluate the diagnostic performance of various DWI parameters. All DWI parameters of renal cortex and medulla were not statistically different between normal allografts and allografts with mild TRAS. Nonetheless, cortical total apparent diffusion coefficient (ADC T) of allografts with moderate TRAS was significantly decreased compared with normal allografts. All cortical and medullary DWI parameters were significantly reduced in severe TRAS compared with normal allografts. ROC curve analysis indicated ADC T could identify severe TRAS with 93.8% sensitivity, 82.4% specificity and an area under the curve of 0.930. ADC T increased significantly after successful angioplasty while it showed no significant change in a patient with unsuccessful angioplasty. DWI is a robust technique that revealed no tissue diffusion and perfusion impairment in mild TRAS. ADC T has good sensitivity and specificity for identifying patients with severe TRAS. DWI is potentially an alternative radiologic biomarker for assessing microstructural and perfusion alterations in TRAS. DWI is useful in detecting renal functional recovery following successful angioplasty. • No altered diffusion and capillary perfusion in mild TRAS • Severe degree TRAS impaired renal allograft diffusion and capillary perfusion properties. • ADC T has good sensitivity and specificity for identifying patients with severe TRAS. • IVIM-DWI parameters increased after successful angioplasty. [ABSTRACT FROM AUTHOR]

Background Previous studies have suggested that B lymphocytes can be polyclonally activated by human cytomegalovirus (HCMV), and individuals infected by HCMV exhibit characteristic features of an autoimmunity disease. B cell-activating factor (BAFF) plays important roles in the survival and differentiation of B cells; however, few studies have examined the potential role of BAFF on B cells infected by HCMV. Methods HCMV virus strain (HCMV AD-169) was concentrated by normal methods and used to infect microbead-purified tonsil CD19+ B cells. Cells and supernatants were collected at the 1st, 3rd, 5th, and 7th day of co-culture, respectively. Cellular phenotypes, including expression of BAFF and its cognate receptors (BAFF-R, TACI, and BCMA) were detected by flow cytometry (FCM); cells apoptosis rates were also examined by FCM; and IgG titers in supernatants was detected by ELISA. In parallel, neutralizing anti-BAFF-R antibody was applied to observe the effect of BAFF/BAFF-R signaling on apoptosis and the IgG secretion ability of B cells stimulated by HCMV. Results LogTCID 50 of 3rd and 4th generation of HCMV was −3.54 and −3.28, respectively. FCM results showed that the purity of CD19 + B cells was >98%. BAFF-R was highly expressed and upregulated on HCMV-infected B cells (93.5%–99.3%), compared with B cells prior to HCMV infection and uninfected group; while BAFF-R expression gradually decreased with time and to the lowest level at 5th day (81%) in the control medium-only group. In contrast, expression of TACI and BCMA gradually increased during culture in both HCMV-infected and medium-only control B cells. Furthermore, the apoptosis rate of HCMV-infected and medium-only control B cells did not vary significantly during culture, but IgG secretion ability of HCMV-infected B cells significantly increased over time while no changes were observed with the medium-only control. Importantly, the apoptosis rate of B cells significantly increased when BAFF/BAFF-R signal was blocked prior to HCMV infection ( P < 0.05), although no significant changes of IgG levels were observed ( P > 0.05). Conclusions BAFF-R was consistently expressed on B cells infected by HCMV. Enhancement of BAFF/BAFF-R signaling decreased the apoptosis rate and extended the survival of B cells. [ABSTRACT FROM AUTHOR]

Prostate cancer (PCa) is the most commonly diagnosed cancer in males and the fifth most common cause of cancer death worldwide. Previous studies indicated that miR-18a-5p modulated epithelial-mesenchymal transition in breast cancer via targeting SREBP1 forming a co-repressor complex with Snail and HDAC1/2. However, the function of miR-18a-5p in prostate cancer remains largely unknown. In this study, we identified miR-18a-5p as a tumor promoter in prostate cancer. miR-18a-5p expression was found upregulated in human prostate cancer tissues while SLC40A1 was down-regulated. Cell proliferation assay demonstrated that miR-18a-5p promoted prostate cancer cell proliferation. We also found SLC40A1 was downregulated by miR-18a-5p in prostate cancer cell lines. Restoration of SLC40A1 reversed the effects of miR-18a-5p in prostate cancer cells. Taken together, our results suggest that miR-18a-5p might function as a tumor-promoting factor in PCa and might contribute to its proliferation. [ABSTRACT FROM AUTHOR]

• Circ_102336 was highly expressed in BC. • Circ_102336 affected BC cell growth and sensitivity to CDDP. • Circ_102336 promoted the tumorigenesis of BC by miR-515-5p. • Biological analysis of circ_102336-miR-515-5p-mRNA interaction. Bladder cancer (BC) ranks as the ninth common human tumor in the world with an increasing incidence. Circular RNAs (circRNAs) have been revealed to exhibit promotive or suppressive impacts on tumor progression of various human cancers, including BC. However, due to the variety of circRNAs, the whole circRNAs network in BC remains unclear. In our study, differentially expressed circRNAs between BC and normal samples in GSE92675 dataset was analyzed by microarray. Circ_102336 was identified to be sharply increased in both BC tissue samples and cell lines, and increased circ_102336 is correlated with a worse overall survival rate of BC patients. Overexpression of circ_102336 dramatically increased the cell proliferation viability of T24 and 5637 cells, while knockdown of circ_102336 exhibited opposite effects. Moreover, circ_102336 knockdown could increase the sensitivity of T24 and 5637 cells to CDDP. In mechanism, circ_102336 was demonstrated to directly bind to and negatively regulate miR-515-5p. Inhibition of miR-515-5p reversed the repressive effects of si-circ_102336 on BC cell proliferation viability. KEGG analysis showed that ATP-binding cassette (ABC) transporters and apoptosis were the major two pathways associated with circ_102336/miR-515-5p axis. therefore, we suggested that circ_102336 indirectly regulate apoptosis and ABC transport pathways through miR-515-5p to finally modulate BC cell proliferation and chemo-resistance. [ABSTRACT FROM AUTHOR]

• A prefabricated 12 m span hybrid steel-laminated bamboo truss designed with BIM software is introduced. • Performance of glubam compression members and connection regions are experimentally studied. • Test results of a full-scale hybrid truss with different support and loading conditions are reported. A 12 m hybrid unsymmetrical steel-glued laminated bamboo (glubam) truss used in a roof construction was designed with building information model (BIM) platform software. The hybrid truss composed of glued laminated bamboo (glubam) as top chords and web members, and steel pipes used as bottom chords. Based on such design outcomes, the manufacture, transportation, prefabrication and installation details, with corresponding advantages, are reported. Experiments of glubam chords and connections were performed. The behaviors of glubam chords along with its load-displacement/strain curves, are given in this research. Experimental results on full-scale truss indicate that it can fulfill the mechanical requirements with respect to deflection limitations and loading bearing capacity. The performance of the truss with end-connection change and under unsymmetrical loading conditions was also experimentally studied and discussed in this research. The prefabricated hybrid truss obtained a relatively right balance between structural requirements and economic benefits, thanks to easy manufacture, transportation, prefabrication, and installation. [ABSTRACT FROM AUTHOR]