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Very few studies have emphasized the effects of high-pressure sintering on snow density evolution, even though snow as a type of engineering material is widely used in construction engineering in cold regions for snow pavement, snow runway and polar infrastructure. This study presents new experimental results of snow densification under high pressures of up to 100 MPa for a temperature range from −3.5 to −17.3°C and uniaxial compression at the temperature of −10°C and constant strain rates from 5 × 10−4 to 10−1 s−1. Results reveal that density evolution of snow to ice under high-pressure sintering can be achieved in a wide temperature range within a duration as short as 5 min. The compressive strength of snow-sintered ice was ~1.2–2.2 times as large as that of water-frozen ice reported by previous work. The orthogonal experiment showed that pressure is a more significant factor affecting the final density in comparison with sintering temperature and time. The increased rates of ice fabrication, low limitations on temperature and reliable sintered snow strength indicate that snow-ice engineering, such as airport construction in Greenland and Antarctica, can be improved by high-pressure sintering of snow to overcome the harsh environment.

Abstract We formulate a finite‐size scaling hypothesis to predict the global permeability of fracture networks. To validate the hypothesis, numerous discrete fracture networks are generated, and the permeability is numerically calculated. Results suggest that the dimensionless permeability, scaled by moments of local conductivity and fracture sizes and corrected by two stereological ratios, can capture variations in fracture attributes (orientations, sizes, and apertures). The universal form obtained in this study can also explain the contradictory observations where the permeability decreases or increases with the domain size of fracture networks. We show that how a clear transition point, where the permeability does not change with the domain size, is obtained from this universal form. This study provides a solid theoretical foundation to understand the connection between fracture attributes and field‐scale hydraulic properties.

The compaction of asphalt mixture is crucial to the performance of the pavement. However, the mix design (i.e., porosity, aggregate size distribution, binder content), which is based on compaction results, remains largely empirical. It is difficult to relate the aggregate size distribution and the asphalt binder properties to the compaction curve in both the field and laboratory compaction of asphalt mixtures. In this paper, the author proposes a simple mathematical model from the perspective of granular physics to predict the compaction of asphalt mixtures. In this model, the compaction process is divided into two mechanisms: (i) viscoplastic deformation of an ordered granular-fluid assembly, and (ii) the transition from an ordered system to a disordered system due to particle rearrangement. This model could take into account both the viscous properties of the asphalt binder and the grain size distributions of the aggregates, where the viscous deformation is calculated with a proposed governing equation and the particle rearrangement effect is solved using simple DEM simulations. This model is calibrated based on the Superpave gyratory compaction tests in the pavement lab, and the R-squares of model predictions are all above 0.95. The model results are compared with experimental data to show that it can provide good predictions for the experiments, suggesting its potential for enhancing the design of asphalt mixtures.

Polybrominated diphenyl ethers (PBDEs) levels in environmental media have increased over the last 20-25 years in the world. In aquatic environments PBDEs were found to be accumulated along food chain and Endocrine disruptors toxicity. In this study PBDEs were investigated in sediment and fish tissues from Lake Chaohu in central eastern China. There were 10 PBDEs congeners detected out of all 41 PBDEs. BDE-47 was of the highest with 5.17 ng/g in sediment and 58.47 ng/g in fish. PBDEs were evenly distributed across the surface sediment in the whole lake. It implied that the main source of PBDEs may not be an inflow river like Nanfei. Tissue distribution patterns of PBDEs in four fish species were in the order of BDE-47 > BDE-99 > BDE-100 > BDE-66 > BDE-138 > BDE-183 > BDE-154 > BDE-153. Octa- and deca-BDEs were below the detection limit. The concentrations of all PBDE congeners were higher in gills, livers, and kidneys than those in muscles and adipose tissue. Furthermore, PBDEs in different tissues had some different distribution patterns with fish size. Those discrepancies appeared to be correlated with the PBDEs pollution fluxes varying with the change of the year and their metabolism divergences in fish tissues.

AIM:To discuss the long-term postoperative results of bilateral lateral rectus recession (BLR) and unilateral lateral rectus recession-medial rectus resection (RR) in therapy of intermittent exotropia.METHODS: We retrospectively analyzed 213 cases of intermittent exotropia who underwent surgery between 2008 and 2010. The patients were grouped into BLR group and RR group. Motor outcomes were divided into three groups on the basis of the angle of deviation after surgery:overcorrection (esotropia/phoria ＞5△), orthophoria (esotropia/phoria ≤5△to exotropia/phoria ≤10△), and undercorrection/recurrence (exotropia/phoria＞10△). Titmus test was used to evaluate stereoacuity, the stereoacuity ＜800s of arc meaned the patients had stereopsis. Surgical outcome including motor criteria and sensory status were compared at postoperative 6, 12, 24mo and at 36mo examination between groups.RESULTS:At 12, 24mo after surgery, the motor outcomes had no difference (P＞0.05) between groups. However, the motor outcomes at 6, 36mo were signally different in each group, indicating the success rate in RR group at 6mo was higher than that in BLR group (83.02% vs 82.24%, P＜0.05) but the result was contrary at the 3y examination (60.75% vs 43.40%, P＜0.05). No statistical significance were found in the sensory outcomes between the groups at mean of 3.7y follow-up.CONCLUSION:Themotor outcomes in RR group were better than in BLR group at 6mo after surgery, while the 3y outcomes were better in BLR group. This may be due to the recurrence rate of the BLR was lower than the RR group’s.

Otamixaban is a potent (Ki=0.5Â nM) fXa inhibitor currently in late-stage clinical development at Sanofi for the management of acute coronary syndrome. Being unproductive in obtaining a suitable crystal of Otamixaban, the required enantiomeric characterization has been accomplished using vibrational circular dichroism (VCD) spectroscopy. Selected by a spectrum similarity index, the calculated spectra of several higher energy conformers were found to match well with the observed spectra. The characteristic IR bands of these conformers were also identified and attributed to the solvation effect. Combined with both the single crystal x-ray diffraction results for an intermediate and the proton NMR study, the absolute configuration of Otamixaban is unambiguously determined to be (R,R). Keywords: Vibrational circular dichroism, DFT, IR, Absolute configuration, Vicinal protonâproton coupling, scXRD

AIM: To investigate the long-term outcomes after surgery for intermittent exotropia \〖X(T)\〗, constant exotropia with a previously intermittent history and constant exotropia without a previously intermittent history. METHODS: Totally 137 patients with intermittent exotropia or constant exotropia who had underwent surgery were analyzed retrospectively. They were assigned into three groups: group 1, seventy-four patients with X(T); group 2, thirty-eight constant exotropia patients with a previously intermittent history; group 3, twenty-five constant exotropia patients without a previously intermittent history. The surgical outcomes in the ocular deviation and the recovery of stereoacuity were compared separately among the three groups. The average follow-up time was 2.2 years. RESULTS: The successful alignment rates were 78%(group 1), 68%(group 2), 64%(group 3), respectively(group 1 vs group 2, P=0.249; group 1 vs group 3, P=0.153; group 2 vs group 3, P=0.716). Fifty-seven patients(77%)in group 1, five patients(13%)in group 2 and one patient(4%)in group 3 achieved binocularity after surgery(group 1 vs group 2, P<0.001; group 1 vs group 3, P<0.001; group 2 vs group 3, P=0.440). The number of patients who achieved gross stereopsis in group 1, group 2 and group 3 were 66(89%), 27(71%), 8(32%)(group 1 vs group 2, P=0.015; group 1 vs group 3, P<0.001; group 2 vs group 3, P=0.002). Twenty-nine patients(56%)in group 1, 5 patients(24%)in group 2, 1 patients(7%)in group 3 achieved distance stereoacuity(group 1 vs group 2, P=0.013; group 1 vs group 3, P=0.001; group 2 vs group 3, P=0.366). CONCLUSION: Patients with constant exotropia who had a intermittent history have a better surgical result compared with those without a intermittence period in gross stereopsis, but a worse postoperative sensory outcome than patients with X(T)in binocular vision, gross stereopsis, and distant stereoacuity. Constant exotropia patients with a period of X(T)may have missed the optimal timing for treatment, early surgery can optimize the postoperative sensory results.

Suffusion constitutes a major threat to the foundation of a dam, and the likelihood of suffusion is always determined by the internal stability of soils. It has been verified that internal stability is closely related to the grain size distribution (GSD) of soils. In this study, a numerical model is developed to simulate the suffusion process. The model takes the combined effects of GSD and porosity (n) into account, as well as Wilcock and Crowe’s theory, which is also adopted to quantify the inception and transport of soils. This proposed model is validated with the experimental data and shows satisfactory performance in simulating the process of suffusion. By analyzing the simulation results of the model, the mechanism is disclosed on how soils with specific GSD behaving internally unstable. Moreover, the internal stability of soils can be evaluated through the model. Results show that it is able to distinguish the internal stability of 30 runs out of 36, indicating a 83.33% of accuracy, which is higher than the traditional GSD-based approaches.

Dynamic alteration of the epitranscriptome exerts regulatory effects on the lifecycle of oncogenic viruses in vitro. However, little is known about these effects in vivo because of the general lack of suitable animal infection models of these viruses. Using a model of rapid‐onset Marek's disease lymphoma in chickens, we investigated changes in viral and host messenger RNA (mRNA) N6‐methyladenosine (m6A) modification during Marek's disease virus (MDV) infection in vivo. We found that the expression of major epitranscriptomic proteins varies among viral infection phases, reprogramming both the viral and the host epitranscriptomes. Specifically, the methyltransferase‐like 3 (METTL3)/14 complex was suppressed during the lytic and reactivation phases of the MDV lifecycle, whereas its expression was increased during the latent phase and in MDV‐induced tumors. METTL3/14 overexpression inhibits, whereas METTL3/14 knockdown enhances, MDV gene expression and replication. These findings reveal the dynamic features of the mRNA m6A modification program during viral replication in vivo, especially in relation to key pathways involved in tumorigenesis. [ABSTRACT FROM AUTHOR]