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The property of a road base depends on its fine content (FC) and water content/suction. In this study, a cyclic loading test was carried out on road base aggregate with different FCs under controlled suction. The different effects of fines on the accumulated strain of road base aggregate at different FCs and suctions were identified. Under the saturated condition, the accumulated strain increased with FC due to the reduction of soil interparticle friction caused by the inclusion of fines. Under unsaturated conditions, the effect of fines on the accumulated strain depended on the inner structure of the soil. For the 'coarse-graincontrolled soil' (FC in the range of 0%-4%), the accumulated strain increased with the increase of FC due to the reduction of interparticle friction, while for the 'transition soil' (FC in the range of 4%-8%), the accumulated strain decreased with the increase of FC as the major impact of the fines shifted to the enhancement of suction, and the inclusion of fines is beneficial for this case; for the 'fine-grain-controlled soil' (FC in the range of 8%-16%), the accumulated strain increased rapidly with FC as the effect of interparticle friction reduction dominated again. Key words: road base aggregate, fine content, cyclic loading, accumulated strain, unsaturated soil La propriete de la base de la route depend de sa teneur en fines (FC) et de sa teneur en eau/suction. Dans cette etude, l'essai de chargement cyclique a ete effectue sur un agregat de base de route avec differentes teneurs en fines sous des succions controlees. Les differents effets des fines sur la deformation accumulee du granulat de la base de la route a differentes teneurs en fines et suctions ont ete identifies. Dans des conditions de saturation, la deformation accumulee augmente avec la teneur en fines en raison de la reduction de la friction interparticulaire du sol causee par l'inclusion de fines. Dans des conditions non saturees, l'effet des fines sur la deformation accumulee depend de la structure interne du sol. Pour le << sol a gros grains controles (FC dans la gamme de 0-4 %)>>, la deformation accumulee augmente avec l'augmentation de la teneur en fines en raison de la reduction de la friction interparticulaire; tandis que pour le << sol de transition (FC dans la gamme de 4-8%)>>, la deformation accumulee diminue avec l'augmentation de la teneur en fines comme l'impact majeur des fines se deplace vers l'amelioration de la succion, et l'inclusion de fines sera benefique pour ce cas; pour le << sol a grains fins controles (FC dans la gamme de 8-16%)>>, la deformation accumulee augmente rapidement avec la teneur en fines, car l'effet de la reduction de la friction interparticulaire domine a nouveau. [Traduit par la Redaction] Mots-cles : agregat de base de route, teneur en fines, chargement cyclique, deformation accumulee, sol non sature, Introduction Road base aggregates mainly consist of unbound granular materials such as gravel and sand. During a road's service, the road base aggregate can be invaded by fines from particle [...]

The paper studied high-order nonlinear fractional elastic equations that depend on low-order derivatives in nonlinearity and established the existence and uniqueness results by using the Leray–Schauder alternative theorem and Perov's fixed point theorem on an appropriate space under mild assumptions. Examples are given to illustrate the key results. [ABSTRACT FROM AUTHOR]

Municipal mud consists of organic matter naturally deposited in a microbial-rich environment, and its common pre-treatment in the laboratory is normally different from that in situ. In this study, an improved pre-loading method and the common pre-treatment method (by air or oven drying) were first applied to investigate the effect of microorganisms within organic matter on performance of the solidified soils. Results reveal that (i) Atterberg limits in the pre-loading method were higher than those in the drying method; (ii) the time-dependent strength became stable for the solidified soils pre- treated by the drying method, while strength decreased for the soils pre-treated by the pre- loading method; (iii) pH value of solidified soils by the pre-loading method decreased more significantly. After excluding the possible porosity influence on solidified soils, the effects of microorganisms within organic matter were investigated by microbial identification tests, including fluorescence detection and high-throughput sequencing. The pre-treatment procedure changed the vitality and diversity of microorganisms, leading to a rebalance between acid erosion and cement hydration during long- term curing. At the end, the long-term strength of the solidified municipal mud by the traditional pre-treatment method (by air or oven drying) could be overevaluated. Key words: pre-treatment procedure, dredged mud, microorganism, solidification, strength performance, durability. La boue municipale est constituee de matieres organiques deposees naturellement dans un environnement riche en microbes, et son pretraitement courant en laboratoire est normalement different de celui in situ. Dans cette etude, une methode de prechargement amelioree et la methode de pretraitement courante (par sechage a l'air ou au four) ont d'abord ete appliquees pour etudier l'effet du microorganisme dans la matiere organique sur la performance des sols solidifies. Les resultats revelent que : (i) les limites d'Atterberg dans la methode de precharge etaient plus elevees que celles de la methode de sechage; (ii) la resistance en fonction du temps est devenue stable pour les sols solidifies pretraites par la methode de sechage, tandis qu'elle a diminue pour les sols pretraites par la methode de precharge; (iii) la valeur du pH des sols solidifies par la methode de precharge a diminue de maniere plus significative. Apres avoir exclu l'influence possible de la porosite sur les sols solidifies, les effets des microorganismes dans les matieres organiques ont ete etudies par des tests d'identification microbienne, y compris la detection de la fluorescence et le sequencage a haut debit. La procedure de pretraitement a modifie la vitalite et la diversite des microorganismes, entrainant un reequilibrage entre l'erosion acide et l'hydratation du ciment apres un durcissement pendant long terme. Au final, la resistance a long terme de la boue municipale solidifiee par la methode traditionnelle de pretraitement (par sechage a l'air ou au four) pourrait etre surevaluee. Mots-cles : procedure de pretraitement, boue de dragage, micro-organisme, solidification, performance de resistance, durabilite., 1. Introduction Urban river and lake sediments are regularly dredged to prevent flooding or to reclaim the ecosystem of water environments (Tang et al. 2001; Dubois et al. 2009; Samara [...]

Objective To isolate, sequence, and identify biological characterization and complete genome sequencing of a virulent Staphylococcus aureus (S. aureus) bacteriophage vB_SauH_IME522. Methods A phage was isolated from sewage of PLA Chinese General Hospital using a clinically isolated S. aureus strain as host bacteria. The double-layer agar plate was used to determine the optimal multiplicity of infection (optimal MOI) and one-step growth curve. Phage morphology was observed by transmission electron microscopy after purification using sucrose gradient separation. Phage DNA was sequenced using the Illumina Miseq sequencing platform. The complete genome sequence was annotated, then comparative genomics and evolutionary analyses were performed. Results A lytic phage of S. aureus was isolated from hospital sewage and named as vB_SauH_IME522. The optimal MOI of the phage was 0.01. One step growth curve showed that its latent period and burst period were 20 and 200 min, respectively. The burst size was about 89 PFU/cell. Electron microscopy displayed the phage having an icosahedral head (70±1) nm and a long contractile tail (135±2) nm. Genome sequencing results showed that the total length of the phage genome was 140 246 bp and the G+C content accounted for 30.2%. The genomic annotation revealed that the phage contained 223 genes coding proteins, 164 putative promoters, 66 terminators, 4 tRNAs, and 7 resistance-related regions. Phylogenetic analysis suggested that the phage was a member of the genus Kayvirus within the subfamily Twortvirinae. Conclusion A lytic phage of S. aureus vB_SauH_IME522 is identified as a new member of the Twortvirinae subfamily, with strong lytic ability and short latent period.

Salmonella spp. are a leading bacterial cause of acute gastroenteritis globally, resulting in <40% of human cases worldwide and >30% in China (2,3). This serovar frequently has been isolated in [...]

In this paper, we consider the existence of positive solutions for a system of fractional q -difference equations with generalized p -Laplacian operators. By using Guo-Krasnosel'skii fixed point theorem, we obtain some existence results of positive solutions for this system with two parameters under some different combinations of superlinearity and sublinearity of the nonlinear terms. In the end, we give two examples to illustrate our main results. [ABSTRACT FROM AUTHOR]