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Highlights • Cumulative-In-Situ-Injection-Production is a novel method for reservoir development. • Simulation results indicate CIIP is an efficient energy-supplement method. • CIIP is applicable to many kinds of tight reservoirs with highly irregular fractures. • Technology for Electric fluid regulation system of CIIP still need to be improved. Abstract Water flooding and gas injection are two traditional secondary development methods for tight oil reservoirs. Water injection has the problem of small injectivity due to low permeable reservoir matrix while gas injection brings about severe breakthrough because of obvious viscosity difference between gas and oil. These traditional approaches that supplement energy between wells are not highly effective. To fill this gap, this paper proposes an efficient energy-supplement method, continuous in-situ injection and production (CIIP), among fractures for multistage fractured horizontal well (MFHW) in tight oil reservoirs. CIIP divides hydraulic fractures into two kinds, in which odd fractures are used for production while even fractures are for injection. CIIP has three main advantages over traditional water flooding: firstly, it switches displacement interval from between injection and production wells to between hydraulic fractures; secondly, CIIP has a better injectivity compared to traditional water flooding at the same injection pressure; and thirdly, CIIP improves sweep efficiency thereby improving oil recovery. In this paper, a workflow is developed to evaluate the performance of CIIP in a case study. Reservoir properties and micro-seismic (MS) mapping data are analyzed to provide fundamental parameters for building a numerical simulation model, and then history matching is achieved to validate the model. The simulation considers two scenarios of hydraulic fractures: the uniform and non-uniform fractures. Uniform-fracture simulation aims to investigate the mechanisms of CIIP under three fracture models; different fracture half-lengths and the situation of existing high permeable channels between injection and production fractures are also included in uniform-fracture simulation. Non-uniform-fracture simulation, whose fractures are interpreted according to MS mapping results, is devised to demonstrate CIIP's superiority in a realistic way. This study is based on a theoretical approach and the results wait to be further proven in the field. Simulation results demonstrate that CIIP is an efficient energy-supplement method. It helps to maintain reservoir pressure near the initial condition during the thirty-year simulation. Meanwhile, even if ten injection wells are added, CIIP still injects 55% more water than water injection (WI) at the same injection pressure. Uniform-fracture simulation indicates that CIIP has a 2.23% more oil recovery than WI and a 3.74% than depletion. Besides, the influence of high permeable channels between injection and production fractures is insignificant and we can still expect CIIP's good performance when hydraulic fractures hit local natural fractures. The non-uniform-fracture simulation demonstrates that CIIP performs well too when hydraulic fractures are randomly distributed. It also finds outs that the presence of primary fractures in which proppant concentrates is essential to CIIP while the role of natural fractures is trivial compared to the hydraulic fractures. In a word, CIIP is a promising technology for tight oil reservoir development. [ABSTRACT FROM AUTHOR]

• An novel optical color image cryptosystem is presented by using biter-order modified integer nonlinear coupled chaos model in Fresnel diffraction domains. • A biter-order modified integer nonlinear coupled chaos model (INCCM) is designed to enhance the security of the proposed cryptosystem. • Some parameters in the encryption process are regarded as the extra keys to improve the security of the cryptosystem. An optical color image cryptosystem is presented by using bit-level modified integer nonlinear coupled chaos model in Fresnel diffraction domains. Firstly, a bit-level modified integer nonlinear coupled chaos model (INCCM) controlled by linear feedback shift register (LFSR) is designed. Subsequently, a framework of LFSR controlling image encryption is designed, and a bit-level encryption algorithm is desinged. LFSR is used to generate pseudo-random sequence to control bit-scrambling sequence, which improves the security. In addition, this model improves integer nonlinear coupling algorithm saving much running time. The effectiveness and feasibility of the proposed color encryption algorithm are verified by numerical simulation considering various types of attacks. [ABSTRACT FROM AUTHOR]

Abstract: Oxymatrine, a quinolizidine alkaloid, has been widely used for the treatment of hepatitis. In this study, we investigated the hypoglycemic and hypolipidemic effects and new pharmacological activities of oxymatrine, in a high-fat diet and streptozotocin (STZ)-induced diabetic rats. The results demonstrated that oxymatrine could significantly decrease fasting blood glucose, glycosylated hemoglobin (GHb), food and water intake, non-esterified fatty acid (NEFA), total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol levels (LDL-c), and increase serum insulin, liver and muscle glycogen, high density lipoprotein cholesterol (HDL-c), glucagon-like peptide-1 (GLP-1) and muscle glucose transporter-4 (GLUT-4) content in diabetic rats. The results of the histological examinations of the pancreas and liver show that oxymatrine protected the islet architecture and prevented disordered structure of the liver. This study displays that oxymatrine can alleviate hyperglycemia and hyperlipemia in a high-fat diet and STZ-induced diabetic rats might by improving insulin secretion and sensitivity. [Copyright &y& Elsevier]

Abstract: Purpose: Echinacoside (ECH), isolated from Cistanche tubulosa (Schrenk) R. Wight stems, has been reported to enhance bone regeneration in MC3T3-E1 cells in vitro. The objectives of this study were to investigate the antiosteoporotic effect of ECH on bone metabolism in the ovariectomized (OVX) rat model of osteoporosis in vivo. Methods: Fifty-six aged 6 months female Sprague-Dawley rats were randomly assigned into sham-operated group (SHAM) and six OVX subgroups (n =8 each). The OVX rats were then subdivided into six groups treated with vehicle (OVX), Xian-ling-gu-bao (XLGB, 0.5g/kg body weight/day, orally), 17β-estradiol (E2, 50μg/kg body weight/day, orally) or ECH (30, 90, and 270mg/kg body weight, daily, orally) for 12 weeks respectively. We evaluated the pharmacological effects of E2, XLGB and ECH against osteoporosis by evaluating the body weight, uterus wet weight, serum and urine biochemical parameters, bone mineral density (BMD), bone biomechanical properties, bone microarchitecture, bone histomorphology and uterus immunohistochemistry. Results: In OVX rats, the increases of body weight, serum hydroxyproline (HOP) levels, and the decreases of uterus wet weight and BMD were significantly reversed by ECH treatment. Moreover, three dosages of ECH completely corrected the increased urine concentration of calcium (Ca), inorganic phosphorus (P), and HOP observed in OVX rats. Furthermore, Micro-CT analysis results of distal femur showed that all ECH-treated groups notably enhanced bone quality compared to OVX group (p <0.05). Consistent with this finding, total femur BMD and biomechanical strength of tibia were significantly improved (p <0.05) after 12 weeks ECH administration. Histological results also showed the protective activity of ECH through promotion of bone formation and suppression of bone resorption. In addition, the ECH administration also significantly enhanced the expression of ER in the uteri according to immunohistochemical evaluation (p <0.05). Those findings, based on the serum and urine biochemical, BMD, Micro-CT, biomechanical test, histopathological and immunohistochemical parameters, showed that ECH has a notable antiosteoporotic effect, similar to estrogen, especially effective for prevention osteoporosis induced by estrogen deficiency. Conclusion: These results suggest that ECH, as a new class of phytoestrogen, has a remarkable antiosteoporotic activity, and may be a promising candidate for treatment of postmenopausal osteoporosis induced by estrogen deficiency in a natural way through herbal resources. [Copyright &y& Elsevier]

Abstract: Dissimilar metal vacuum brazing between TiAl alloy and 40Cr steel at 900°C for 5min, 10min and 15min was conducted with Ti-based alloy foil as the filler. Five distinct regions were detected in the brazed seam from each joint during microstructure examination. The hardness in the brazed seam was measured much higher than those in the two substrates, and the hardness in the filler metal layer was higher than that in the reaction layer. However, brazing for longer time can reduce the hardness of the brazed seam. The average shear strength of the joint was 26MPa when the joint was brazed for 5min, and it increased to 32MPa when brazed for 10min and 15min. The specimen brazed for 5min fractured through the interface between 40Cr steel base metal and filler metal layer, but the specimen brazed for 10min and 15min fractured through the filler metal layer in the brazed seam. It was found that the compositions of the filler material and sufficient interdiffusion between the filler and substrates are important to improve the joint strength, and the mechanical properties of the filler metal also control the strength of the resultant joint. [Copyright &y& Elsevier]

Graphical abstract Highlights • L. cubeba and M. arvensis oils can be used as green repellents for mosquito control. • The optimal formula of the repellent liquid was defined as "10% L. cubeba oil + 10% M. arvensis oil + 5 % Tween 80 + 5% vanillin + 70% absolute ethyl alcohol" (essential oil volume ratio of 1:1). • The effective hand skin protection time of optimal formula is 4 h , which can be used as green repellents for mosquito control because of their environmental friendliness. Abstract The repellent activities of 12 selected essential oils against Aedes albopictus were evaluated using a Y-tube olfactometer. Mentha arvensis oil showed the best repellent activity among the selected oils, with 91.66% percentage repellency at 20 min, followed by Litsea cubeba oil (73.94%) and Laurus nobilis oil (67.12%). The repellent activities of nine designed and prepared repellent liquid formulas were tested against Ae. albopictus using the arm-in-cage method. The optimal formula of the repellent liquid was defined as "10% Litsea cubeba oil + 10% Mentha arvensis oil + 5% Tween 80 + 5% vanillin +70% absolute ethyl alcohol." The effective hand skin protection time of this liquid formula is 4 h, indicating its potential product development value. L. cubeba and M. arvensis oils can be used as green repellents for mosquito control because of their low toxicity and environmental friendliness. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Background Glucocorticoid hormones are implicated in the pathogenesis of Alzheimer's disease (AD) and other diseases including diabetes, hyperlipidemia, and osteoporosis. Akebia saponin D (ASD) possesses numerous pharmacological activities, including as an anti-AD, anti-hyperlipidemia, anti-diabetes, and anti-osteoporosis agent. The anti-AD effect of ASD is possibly through its regulation of glucocorticoid levels. Purpose The present study was undertaken to investigate the neuroprotective effects of ASD on Aβ 25-35 -induced cognitive deficits and to elucidate its underlying mechanism of action. Methods The AD rat model was established by an intracerebroventricular injection of Aβ 25-35 into the lateral ventricles. Spatial learning and anxiety state were assessed by Morris water maze task and elevated plus-maze assay, respectively. The degree of hypertrophy of adrenal gland was analyzed using the viscera coefficient. Corticosterone and ACTH concentrations in the plasm were measured using biochemical assay kits. The activity of 11β-hydroxysteroid dehydrogenase type-1 (11β-HSD1) in liver and groin fat pad was assessed by measuring cortisol production. Results Compared with the control group, AD rats displayed significant spatial learning and reference memory impairments, serious anxiety disorders, obvious hypertrophy of adrenal gland, elevated corticosterone and ACTH levels in the plasma, and increased 11β-HSD1 activity in liver and groin fat pad. ASD could significantly ameliorate the memory deficits and anxiety symptoms, markedly reduce the viscera coefficient of adrenal gland, observably decrease corticosterone and ACTH concentrations, and showed no effect on the activity of 11β-HSD1. Conclusions These results indicate that ASD might exert a significant neuroprotective effect on cognitive impairment, driven in part by reducing systemic corticosterone level by down-regulation of the hypothalamic-pituitary-adrenal (HPA) axis. [ABSTRACT FROM AUTHOR]

Nanocomposite hydrogels with interpenetrating polymer network (IPN) structure based on poly(ethylene glycol) methyl ether methacrylate modified ZnO (ZnO-PEGMA) and 4-azidobenzoic agarose (AG-N 3 ) were prepared by a one-pot strategy under UV irradiation. The hydrogels exhibited a highly macroporous spongelike structure, and the pore size decreased with the increase of the ZnO-PEGMA content. Due to the entanglement and favorable interactions between the two crosslinked networks, the IPN hydrogels exhibited excellent mechanical strength and light transmittance. The maximum compressive and tensile strengths of the IPN hydrogels reached 24.8 and 1.98 MPa respectively. The transparent IPN hydrogels transmitted more than 85% of visible light at all wavelengths (400–800 nm). The IPN hydrogels exhibited anti-adhesive property towards Gram-negative Escherichia coli ( E. coli ) and Gram-positive Staphylococcus aureus ( S. aureus ), and the bactericidal activity increased with the ZnO-PEGMA content. The incorporation of ZnO-PEGMA did not reduce the biocompatibility of the IPN hydrogels and all the IPN nanocomposites showed negligible cytotoxicity. The present study not only provided a facile method for preparing hydrogel nanocomposites with IPN structure but also developed a new hydrogel material which might be an excellent candidate for wound dressings. [ABSTRACT FROM AUTHOR]

• Heat transfer enhancement of zeotropic mixtures was studied. • Regulating mass transfer resistance was conducted by constructing surface structure. • Multi-cone staggered structure reduces mass transfer resistance and improve heat transfer. The mass transfer resistance is a significant element leading to heat transfer degradation of zeotropic mixtures in the flow boiling. In this paper, the heat transfer enhancement of zeotropic mixtures in the flow boiling was investigated through regulating the mass transfer resistance by constructing reasonable surface structure. The heat and mass transfer, pressure drop characteristics of stratified bubble flow for R134a/R245fa zeotropic mixtures in a rectangular channel with multi-cone staggered spoiler porous structure were studied experimentally. The bottom of channel was sintered with multi-cone staggered porous layer with thickness/height/diameter of 1/3/2 mm, respectively. The experiments were carried out under an inlet evaporation temperature of 20 ℃, and the ranges for heat and mass fluxes were 10–150 kW/m2 and 100–150 kg/(m2·s), individually. Compared to the rectangular channel with smooth porous structure, liquid mass transfer resistance of zeotropic mixtures in the rectangular channel with multi-cone staggered porous structure was decreased obviously. The decrease degree for Mixture 2 was largest, while the maximum average decrease was 89.61 % at G = 100 kg/(m2·s). The heat transfer coefficients were obviously improved and heat transfer enhancement increased gradually especially under conditions of high heat flux. The enhancement degree for Mixture 2 was the largest, while the maximum average increase was 26.05 % at G = 100 kg/(m2·s). The pressure drop increased significantly, and the increasing degree for Mixture 2 was smallest, while the minimum average increase was 38.18 % at G = 150 kg/(m2·s). Multi-cone staggered structure was helpful to reduce liquid mass transfer resistance and improve heat transfer performance for zeotropic mixture. The zeotropic mixture with higher liquid mass transfer resistance would have better heat transfer intensify and smaller increase of pressure drop with the help of multi-cone staggered structure. [ABSTRACT FROM AUTHOR]

For unconventional reservoirs, water flooding performs poorly because of low displacement efficiency; gas flooding shows limited enhanced oil recovery (EOR) capability due to gas breakthrough. Carbonated water injection (CWI) and active CWI (ACWI) are promising EOR methods which combine advantages of water and gas flooding. This paper provides experimental and numerical studies of carbonated water and surfactant injection based on a case study in Changqing Oilfield, China, which is the first time to investigate the feasibility of CWI and ACWI for tight oil reservoirs. This study compares performances of active water injection (AWI), CWI, Water altering gas (WAG), and ACWI. Experimental results reveal that the oil recovery of CWI is 2.7% more than WAG. ACWI achieves the highest incremental oil recovery (9.43%) among four methods. The sensitivity analyses of ACWI + WAG is further implemented experimentally, which demonstrates that ACW as a pre-flood improves 7% of oil recovery during WAG process. For Changqing tight reservoir cores, the optimal injection volume of ACW is 0.8 pore volume. Numerical simulations are conducted to validate the capability of cubic Equation-of-State coupled with Henry's law (EOS/H model) for CWI in tight oil reservoirs, indicating EOS/H model is applicable to correlate phase behavior of carbonated water and oil system. This paper, for the first time, investigates the EOR performance of ACWI in tight oil reservoirs. These results explore the feasible application of using CWI/ACWI in tight oil reservoir development. • Active carbonated water injection has potential application for tight oil EOR. • ACWI followed by WAG can further improve oil recovery for tight oil reservoirs. • The critical injected active carbonated water volume is about 0.8 PV during ACWI+WAG. • The cubic equation of state coupled with Henry's law can simulate CWI more accurately. [ABSTRACT FROM AUTHOR]

Emodinol, 1β, 3β, 23-trihydroxyolean-12-en-28-acid, as the main active ingredient firstly extracted from the rhizomes of Elaeagus pungens by our Research Group, was identified with apparent uricosuric and nephroprotective effects in hyperuricemia mice in our previous study. This study aimed to investigate the renal protective effect of emodinol in urate nephropathy rats. Rats were orally administrated by combined adenine and ethambutol to induce urate nephropathy. Emodinol at various doses were administered intragastrically to urate nephropathy rats daily. Serum uric acid (Sur), serum creatinine (Scr) and blood urea nitrogen (BUN) levels, as well as Interleukin-1beta (IL-1β) and tumor necrosis factor- alpha (TNF-α) concentrations in serum and kidney were determined. Renal protein expressions of organic ion transporters, components of NLR pyrin domain containing 3 (NLRP3) inflammasome, as well as key factors involved in toll-like receptors (TLRs)/myeloid differentiation factor 88 (MyD88)/nuclear factor kappa B (NF-κB) signaling pathway were analyzed by western blot. Emodinol significantly decreased Sur, Scr and BUN levels in adenine and ethambutol − induced urate nephropathy rats. More importantly, emodinol reversed dys-expression of organic ion transporters, inhibited NLRP3 inflammsome activation and suppressed TLRs/MyD88/NF-κB signaling pathway in the kidneys of urate nephropathy rats. Consistently, dilated tubules and tubular UA crystal formation, as well as tubular interstitial inflammatory cells infiltration in kidneys of urate nephropathy rats were obviously attenuated by emodinol, accompanied by restored renal and serum inflammatory cytokines concentrations. Taken together, the date suggested that emodinol ameliorated urate nephropathy by regulating renal organic ion transporters and inhibiting immune inflammatory responses in rats. [ABSTRACT FROM AUTHOR]

Highlights: [•] High glucose induces cytotoxicity and apoptosis in endothelial cells. [•] Timosaponin B-II protects endothelial cells from cytotoxicity and apoptosis. [•] Timosaponin B-II decrease high glucose-induced oxidative stress. [ABSTRACT FROM AUTHOR]

Three unprecedented 23-nor-3,4- seco -3-acetallupane triterpenoids, gracilistylacid A-C (1 – 3), along with three known lupanoids (4 – 6), were isolated from the aerial parts of Acanthopanax gracilistylus W.W. Smith var. gracilistylus. Compounds 1 – 3 may be biosynthetically formed via carboxylation, decarboxylation, cycloreversion, and aldolization reactions based on impressic acid (4). The structures of all compounds were characterized by spectroscopic techniques and X-ray craystallographyic studies. Compounds 3 and 4 exerted anti-osteosarcoma effects through an inhibition of cell migration and vasculogenic mimicry (VM) formation in 143B cells in vitro. [Display omitted] • Three novel 23-nor-3,4-seco-3-acetallupane triterpenoids obtained from AGG • All isolates were evaluated their anti-osteosarcoma effect in 143B cell lines in vitro. • Compounds 3 and 4 exhibited an inhibition of cell migration and vasculogenic mimicry formation. [ABSTRACT FROM AUTHOR]

Abstract: Echinacoside (ECH), isolated from Cistanche tubulosa (Schrenk) R. Wight stems, was subjected to in vitro experiments to investigate its bioactivities on proliferation, differentiation and mineralization of the osteoblastic cell line MC3T3-E1. MTT assay, the alkaline phosphatase (ALP) activity and calcium deposition were determined, and the secretion of collagen I (COL I), osteocalcin (OCN), osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) were also assayed by enzyme-linked immunosorbent assay (ELISA). The results showed that ECH caused a significant increase in cell proliferation, ALP activity, COL I contents, OCN levels and an enhancement of mineralization in osteoblasts at the concentration range from 0.01 to 10nmol·L−1 (p<0.05), suggesting that ECH has a stimulatory effect on osteoblastic bone formation or has potential activity against osteoporosis. In addition, the ratio of OPG/RANKL also could be enhanced by ECH. These findings provide the potent evidence that ECH can promote bone regeneration in cultured osteoblastic MC3T3-E1 cells, which might be done by elevating the OPG/RANKL ratio, and potential evidence for echinacoside to be a promising drug or a lead compound in the development of disease-modifying drug to prevent osteoporosis. [Copyright &y& Elsevier]

Abstract: Ethnopharmacological relevance: Smilax china L., popularly known as “Jin Gang Ten”, has been widely used as a traditional herbal medicine for the treatment of gout, rheumatoid arthritis and other diseases for a long time in China. Aim of study: The present study was carried out to investigate the effect of Smilax china L. on hyperuricemia and renal dysfunction in induced hyperuricemic animals. Materials and methods: Five fractions (petroleum ether, chloroform, ethyl acetate, n-butanol and residual ethanol fraction) of Smilax china L. were orally administered to potassium oxonate-induced hyperuricemic mice for three days. The xanthine oxidase inhibitory activities and modes of action of nine compounds isolated from ethyl acetate fraction (EAF) were then examined in vitro. Finally, different dosages of EAF were administered to 10% fructose-induced hyperuricemic rats. Results: EAF (250mg/kg) exhibited stronger anti-hyperuricemic activity in hyperuricemic mice compared with the other four fractions. Caffeic acid, resveratrol, rutin and oxyresveratrol isolated from EAF showed different inhibitory activities on xanthine oxidase in vitro, with the IC50 values of 42.60, 37.53, 42.20 and 40.69μM, respectively, and exhibited competitive or mixed inhibitory actions. Moreover, EAF (125, 250 and 500mg/kg) markedly reversed the serum uric acid level (p <0.05, p <0.01 and p <0.001, respectively), fractional excretion of urate (p <0.05, p <0.01 and p <0.01, respectively) and blood urea nitrogen (p <0.05, p <0.01 and p <0.01, respectively) to their normal states, and prevented the renal damage against tubulointerstitial pathologies in hyperuricemic rats. Conclusion: These findings show that Smilax china L. exhibits anti-hyperuricemic and nephroprotective activity in hyperuricemic animals. [Copyright &y& Elsevier]

Abstract: Akebia saponin D is a typical bioactive triterpenoid saponin isolated the rhizome of Dipsacus asper Wall. Our previous studies demonstrated that the oral bioavailability of akebia saponin D was very low, but the underlying mechanisms remained unknown. The present study aims to investigate the intestinal absorptive characteristics of akebia saponin D as well as the absorptive transport behavior influenced by co-administration of three absorption-enhancing agents and three efflux protein inhibitors using an in vitro everted gut sac method and an in situ intestinal perfusion model. The results showed that akebia saponin D had a quite limited intestinal permeability, and there was a non-linear increase in transepithelial transportation with increasing concentrations of akebia saponin D. The absorption of akebia saponin D was intestinal segment selective and the small intestine was the best absorptive site. Among three absorption promoters, borneol could significantly improve the permeability of akebia saponin D across ileum, while Tween-80 and DMSO had almost no absorption-enhancing effect. In addition, verapamil, probenecid and pantoprazole in the perfusates were used in this study as modulators of transporters such as P-glycoprotein, MRPs and BCRP in the intestinal mucosa, respectively. The results exhibited that the ileal permeability of akebia saponin D was markedly elevated by the co-administration of probenecid, indicating that akebia saponin D may be likely a substrate of MRPs. The above-mentioned results suggest that akebia saponin D has a poor intestinal absorption not only due to its poor transepithelial permeability but also owing to the contribution of efflux transporters such as MRPs in the intestine. [Copyright &y& Elsevier]

Abstract: The objectives of this study were to investigate the protective effects of Eucommia ulmoides Oliv. (EUO) bark and leaf against cytotoxicity induced by amyloid-β peptide (Aβ) and to explore their active components. The PC-12 cells injury mediated by Aβ25–35 was employed to assess the neuroprotective effects of EUO bark, EUO leaf and various compounds. Intracellular Ca2+ determination, MTT reduction assay, lactate dehydrogenase leakage evaluation and HO33258/PI staining were used to quantitatively or qualitatively evaluate cell viability and injury. The organic solvents partition and the macroporous resin separation were also applied to tracing the active constituents of EUO bark. Moreover, the effects of 8 compounds (3 iridoid glucoside, 3 phenylpripanoids and 2 flavonoids) were tested to identify the active compounds of EUO leaf. The results demonstrated that the water extracts of EUO barks and leaves, geniposidic acid and chlorogenic acid could efficiently protect PC-12 cells against the cytotoxicity of Aβ25–35. This research suggests that EUO may represent a potential treatment strategy for Alzheimer''s disease. Meanwhile, geniposidic acid and chlorogenic acid are the major active constituents of EUO barks and leaves, respectively. [Copyright &y& Elsevier]

Air pollution exposure during daily traveling is growing as an increasingly serious factor affecting public health with rapid incensement of travel distance in urban sprawl. Finding a healthier route with least exposure risk might be an alternative way to mitigate adverse health outcomes under the truth that worldwide air pollution in urban area cannot be eliminated within a short period of time. Integrating techniques of fine scale mapping of air pollutant concentration, risk weight estimation of road segment exposure to air pollutants, and dynamic Dijkstra algorithm capable of updating route, this study for the first time proposes a healthier route planning (HRP) method to minimize personal travel exposure risk to air pollution. Effectiveness of HRP in mitigating exposure risk was systematically tested based on hundred pairs of origins and destinations located in Beijing-Tianjin-Hebei (BTH) of China with necessarily dense air quality observations. Results show that the spatiotemporal variations of air pollutant concentrations were significant and these differences indeed occurred with time at hourly scale. Meanwhile, the grid-based estimation of exposure risk is time dependent with risk ranging from 5 to 109, which echoes the necessity of healthier route planning. Compared to routes with the shortest distance and least travel time, healthier route has the least exposure risk. And this risk mitigation effect is more significant in areas with wide exposure risk variations than those in areas without obvious risk difference over space (e.g., 21.38% vs. 0.86%). Results suggest that HRP method is promising to minimize personal exposure risk during daily travel based on the accurate exposure risk estimation of road segment at high spatiotemporal resolution. This role could be more important in areas with longer travel distance and greater heterogeneous distribution of air pollution in great metropolis. • A near real-time health route search method was proposed and validated. • Dynamic risk update mechanism is needed for near real-time health route search. • Accurate exposure risk estimation depends on fine scale air pollution mapping. • Personal air pollution exposure can be minimized through the planned health routes. [ABSTRACT FROM AUTHOR]