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The widespread application of polylactide (PLA) has been limited by its slow crystallization rate and poor toughness. In the present work, a low molecular weight nucleator, TMC 301, and polyamide elastomer (PAE) were incorporated into PLA through melt blending to mediate both the crystallization capability and impact toughness. It was found that the introduction of TMC 301 decreased the crystallization temperature of PLA during the cooling process, while enhancing its cold crystallization capacity of PLA in the heating scan. Accordingly, the presence of TMC 301 shortened the half-crystallization time of PLA at 95°C in the ternary blends with minimal influence on the Avrami index. Moreover, the dispersion size of PAE decreased when the concentration of TMC 301 increased to 0.3 wt%, leading to a substantial increase in the tensile toughness and the impact strength of the PLA/PAE/TMC 301 blend. It is suggested that the size of the elastomer particles is a critical factor influencing the toughening efficiency of TMC301 in PLA/PAE blends. The nucleator TMC 301 and polyamide elastomer (PAE) were incorporated into PLA through melt blending to enhance both crystallization capability and toughness. The phase structure, crystallization behavior and the mechanical performances were studied. [ABSTRACT FROM AUTHOR]

Gel‐spinning of ultra‐high molecular weight polyethylene (UHMWPE) fibers has attracted great interest in academia and industry since its birth and commercialization in the 1980s, due to unique properties such as high modulus, low density, and excellent chemical resistance. However, the high viscosity and long relaxation time greatly complicate processing. In industry, solvents, like decalin and paraffin oil, usually disentangle the physical networks and promote final drawability. From extruding the polymer solution to post‐solid‐stretching, many polymer physics problems that accompany high‐modulus fiber gel‐spinning should be understood and addressed. In this review, by detailed discussions about the effect of entanglements and intracrystalline chain dynamics on the mechanical properties of UHMWPE, theoretical descriptions of the structure formation of disentangled UHMWPE crystals, and the origin of high modulus and strength of final fibers are provided. Several physical intrinsic key factors are also discussed, revealing why UHMWPE is an ideal material for producing high‐performance fibers. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing enables effective exploitation of deep coalbed methane. During the hydraulic fracturing process, high salinity flowback fluid is generated, and this poses a significant challenge for water treatment. Therefore, we investigate the effect of hydraulic fracturing on ion migration in deep coal seams and its underlying mechanisms. In this study, nuclear magnetic resonance, inductively coupled plasma mass spectrometry, scanning electron microscopy, and energy dispersive x-ray spectroscopy were utilized to systematically study the diffusion behavior of ions and its correlation with water imbibition. Our results show that imbibition equilibrium was reached before ion diffusion finished. Ion diffusion displays three linear stages followed by a plateau part, and the second segment is the fastest one. The water–coal interactions result in the diffusion of ions into solution, with the most significant increases in Ca2+, Mg2+, Na+, K+, Li+, Cu2+, V5+, Hg2+, Pb2+, B3+, Mo6+, Cr3+, Sn4+, Cd2+, Cs+, Sr2+, and Ba2+. The dissolution of calcite, sodium feldspar, and kaolinite are the main contributions for ion migration. In addition, these reactions not only cause the release of ions into the solution but also lead to the formation of secondary pore-fractures and secondary precipitation. The results of this work help to understand better the ion migration induced by the water–coal interaction and to evaluate the fluid properties in deep coal formations. [ABSTRACT FROM AUTHOR]

Core analysis is an accurate and direct method for finding the physical properties of oil and natural gas reservoirs. However, in some cases coring is time consuming and difficult, and only cuttings with the drilling fluid can be obtained. It is important to determine whether cuttings can adequately represent formation properties such as porosity, permeability, and pore size distribution (PSD). In this study, seven limestone samples with different sizes were selected (Cubes: 4 × 4 × 4 cm, 4 × 4 × 2 cm, 4 × 2 × 2 cm and 2 × 2 × 2 cm, Core: diameter of 2.5 cm and a length of 5 cm, Cuttings: 1–1.7 mm and 4.7–6.75 mm in diameter), and low-field nuclear magnetic resonance (NMR) measurements were performed on these samples to obtain porosity, PSD, and permeability. The results showed that the porosity of cubes and cuttings with different sizes are consistent with cores, which is about 1%. Whereas the PSDs and permeabilities of the two cutting samples (less than in size 6.75 mm) differ significantly within cores. It is suggested that interparticle voids and mechanical pulverization during sample preparation have a negligible effect on porosity and a larger effect on PSD and permeability. Combined with factors such as wellbore collapse and mud contamination suffered in the field, it is not recommended to use cuttings with a particle size of less than 6.75 mm to characterize actual extra-low porosity and extra-low permeability formation properties. [ABSTRACT FROM AUTHOR]

As a model system for thermal interface materials (TIMs), the complex rheological behavior of polydimethylsiloxane oligomer (oDMS)/alumina sphere particles (AlS) suspensions (i.e., oDMS/AlS) is investigated systematically in this work. Aluminum particles with 1 and 10 μm were used as fillers. Here, a surface treatment by using a silane coupling agent as found to be effective in improving the fluidity of the suspensions with small sized AlS particles. Peculiar large amplitude oscillatory shear (LAOS) results were observed for the suspensions that exhibited three or four responses (Hookean regime, shear softening, shear hardening and a second shear softening) depending on the surface properties of AlS particles. For the oDMS/AlS10 neat system, the width of the Hookean regime is determined by the shear stress (τ) instead of the shear strain (γ), whereas it completely disappears in the oDMS/AlS10t system due to the increase potential energy between particles. Both critical stress and strain at the onset point for strain hardening decreased with the increase of particle concentration. Frequency dependent measurements illustrates that it is the critical strain instead of the stress that controls the shear hardening behavior. Average distance of neighboring particles is assumed to play a key role in the formation of hydroclusters. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are a group of highly toxic organic pollutants. At present, there has only been limited research into PAH contamination in Tangxun Lake and Dong Lake, which are the first and second largest urban inland lakes in China, respectively. This study investigated the concentration, spatial distribution, sources, and ecological risks of PAHs in the water from Dong Lake and Tangxun Lake. The focus of this study is to use models to analyze the sources of PAHs, as well as their potential toxicity to humans, in the water bodies of Dong Lake and Tangxun Lake. This study performed liquid–liquid extraction to extract PAHs from lake water samples using dichloromethane and then used gas chromatography–mass spectrometry (GC-MS) to quantitatively analyze the PAHs in the samples. The total concentration of the ∑16PAHs showed high variability among different sampling points, ranging from 12.92 to 989.09 ng/L, with an arithmetic mean of 121.97 ng/L. The composition of the ∑16PAHs was mainly concentrated at a low molecular weight (>70%). The molecular distributions of PAH studies, combined with positive matrix factorization (PMF), indicate that oil and coal combustion are the main sources of PAHs in Dong Lake and Tangxun Lake. The model of PMF succeeded in identifying and quantifying five sources with similar contributions: the combustion of petroleum products, heavy oil burning, coal combustion, traffic emissions, and natural gas and oil combustion mixed. According to toxicity equivalency (TEQ) and lifelong cancer risk (ILCR) research, PAHs from traffic sources in the environment may be more toxic, and the potential carcinogenic risk of PAH pollution to humans in Tangxun Lake and Dong Lake water bodies is relatively inferior. [ABSTRACT FROM AUTHOR]

Background: NADPH oxidase 2 (NOX2) is highly expressed in injured brain tissues. We determined serum NOX2 levels of aneurysmal subarachnoid hemorrhage (aSAH) patients and further investigated correlation of serum NOX2 levels with disease severity, delayed cerebral ischemia (DCI) plus prognosis after aSAH. Methods: Serum NOX2 levels were measured in 123 aSAH patients and 123 healthy controls. World Federation of Neurological Surgeons scale (WFNS) score and modified Fisher (mFisher) score were utilized to assess disease severity. Modified Rankin scale (mRS) score was used to evaluate the clinical prognosis at 90 days after aSAH. Relations of serum NOX2 levels to DCI and 90-day poor prognosis (mRS score of 3– 6) were analyzed using multivariate analysis. Receiver operating characteristic curve (ROC) was built to evaluate the prognostic predictive capability. Results: Serum NOX2 levels in aSAH patients, compared with healthy controls, were significantly increased, and were independently correlated with WFNS score, mFisher score and post-stroke 90-day mRS score. Patients with poor prognosis or DCI had significantly higher serum NOX2 levels than other remainders, and serum NOX2 levels independently predicted 90-day poor prognosis and DCI. Serum NOX2 had high prognosis and DCI predictive abilities, and their areas under ROC curve were similar to those of WFNS score and mFisher score. Conclusion: Serum NOX2 levels are significantly associated with hemorrhage severity, poor 90-day prognosis and DCI in aSAH patients. Hence, complement NOX2 may serve as a potential prognostic biomarker after aSAH. [ABSTRACT FROM AUTHOR]

The Paleocene Kongdian Formation coarse clastic rock reservoir in Bozhong Sag is rich in oil and gas resources and has huge exploration potential. However, the coarse clastic rock reservoir has the characteristics of a complex pore structure and strong heterogeneity, which restrict the accuracy of evaluating the reservoir's physical properties, such as porosity and permeability, for field evaluation. Nuclear magnetic resonance (NMR) technology has become a popular methods for unconventional reservoir evaluation because it can obtain abundant reservoir physical property information and because of its ability to identify fluid characteristics information. The transverse relaxation time (T2) cutoff (T2C) value is an important input parameter in the application of NMR technology. The accuracy of the T2C value affects the accuracy of the reservoir evaluation. The standard method for determining the T2C value requires a series of complicated centrifugation experiments in addition to the NMR experiments, and its application scope is limited by obtaining enough core samples. In this study, 14 core samples from the coarse clastic rock reservoir in the southwestern Bozhong sag of the Bohai Bay Basin were selected, and NMR measurements were carried out under the conditions of fully saturated water and irreducible water to determine the T2C value. Based on the multifractal theory, the NMR T2 spectrum of the saturated sample was analyzed, and the results show that the NMR T2 distribution of the saturated sample has multifractal characteristics, and the multifractal parameter Dq and the singular intensity range Δα have a strong correlation with the T2C value. Thus, based on multiple regression analyses of the multifractal parameters with the experimental T2C value of 10 core samples, we propose a method to predict the T2C value. After applying this method to 4 samples that were not used in the modeling, we confirmed that this method can be used to predict the T2C value of core samples. Furthermore, we expanded this method to the field application of a production well in Bozhong sag by adding an empirical index in the model. The new model can be used to directly calculate the T2C value of NMR logging data, and it does not require any other extra data, such as those from core analysis. This method is applicable in fast reservoir evaluations by only using NMR logging data in the field. The research results improve the accuracy of field NMR logging reservoir evaluations. [ABSTRACT FROM AUTHOR]

Objective: The complement cascade is activated early following intracerebral hemorrhage (ICH) and causes acute brain injury. We intended to explore the effects of plasma complement component 1q (C1q) levels on hemorrhagic severity and functional outcome in ICH patients. Methods: In this prospective cohort study, we measured the plasma C1q levels of 101 ICH patients and 101 healthy controls. The Glasgow Coma Scale (GCS) score and hematoma volume were used to assess the ICH severity. Poor prognosis was referred to as a Glasgow Outcome Scale (GOS) score of 1-3 at three months following a stroke. A multivariate logistic regression model was configured to determine the independent relation of plasma C1q levels to severity and poor prognosis. Under receiver operating characteristic (ROC) curve, prognostic capability of plasma C1q levels was evaluated. Results: There was a significant elevation of plasma C1q levels in patients, as compared to controls [median (percentiles 25th-75th), 225.04 mg/l (156.10-280.15 mg/l) versus 88.18 mg/l (70.12-117.69 mg/l); P<0.001]. Plasma C1q levels of patients were independently related to GCS score (t =-3.281, P=0.001) and hematoma volume (t = 2.401, P=0.018), and were highly correlated with the GOS score at 3 months post-stroke (r=-0.658, P<0.001). Plasma C1q levels were obviously higher in poor prognosis patients than in other remainders (median percentiles 25th-75th), 278.40 mg/l (213.81-340.05 mg/l) versus 174.69 mg/l (141.21-239.93 mg/l); P<0.001). Under the ROC curve, plasma C1q levels significantly discriminated the development of poor prognosis (area under ROC curve 0.795; 95% confidence interval, 0.703–0.869; P<0.001). Using maximum Youden method, plasma C1q levels > 270.11 mg/l distinguished patients at risk of poor prognosis at 3 months with 56.52% sensitivity and 94.55% specificity. Meanwhile, the prognostic predictive ability of plasma C1q levels was equivalent to those of GCS score and hematoma volume (both P>0.05). Moreover, plasma C1q levels > 270.11 mg/l independently predicted a poor prognosis at 3 months (odds ratio, 4.821; 95% confidence interval, 1.211-19.200; P=0.026). Conclusion: Plasma C1q levels are closely related to the illness severity and poor prognosis of ICH at 3 months. Hence, complement C1q may play an important role in acute brain injury after ICH and plasma C1q may represent a promising prognostic predictor of ICH. [ABSTRACT FROM AUTHOR]

The self‐nucleation behavior of a polybutene‐1/ethylene random copolymer, P(B1‐ran‐E), which undergoes a complex crystal‐crystal transition behavior, has been studied in detail. Similar to PE random copolymers, this material shows a strong melt memory effect even above equilibrium melting point of PB‐1 homopolymer. Different polymorphic forms can be obtained when P(B1‐ran‐E) is cooled from different self‐nucleation domains. The trigonal form I′ could only be nucleated in the presence of remaining form I crystals via self‐seeding, while the melt memory in Domain IIa could only act as self‐nuclei for kinetically favored form II. Furthermore, observations from optical microscopy illustrated that melt memory is able to enhance nucleation density but it does not affect the spherulitic growth rate. [ABSTRACT FROM AUTHOR]

Objective. Recent years, there has been a rapid increase in the incidence of esophageal adenocarcinoma (EAC), while the prognosis for patients diagnosed remains poor and has slightly improved. Methods. We extracted 6,466 cases with detailed demographical characteristics including age at diagnosis, sex, ethnicity, marital status, and clinical features, involving tumor grade and stage at diagnosis and treatment modalities (radiation therapy, chemotherapy, and surgery) from the Surveillance, Epidemiology, and End Results (SEER) (1975–2017) dataset. They were further randomly divided into the training and validating cohorts. Univariate and multivariate Cox analyses were conducted to determine significant variables for construction of nomogram. The predictive power of the model was then assessed by Harrell concordance index (C-index) and the area under the curve (AUC) of the receiver operating characteristic (ROC) curve. Results. Multivariate analysis revealed that age, marital status, insurance, tumor grade, TNM stage, surgery, and chemotherapy all showed a significant association with overall survival (OS) and cancer-specific survival (CSS). These characteristics were employed to build a nomogram. Particularly, the discrimination of nomogram for OS and CSS prediction in the training set were excellent (C-index = 0.762, 95% CI: 0.754–0.770 and C-index = 0.774, 95% CI: 0.766–0.782). The AUC of the nomogram for predicting 2- and 5-year OS was 0.834 and 0.853 and CSS was 0.844 and 0.866. Similar results were observed in the internal validation set. Conclusion. We have successfully established a novel nomogram for predicting OS and CSS in EAC patients with good accuracy, which can help clinicians predict the survival of individual patient survival and provide optimal treatment strategies. [ABSTRACT FROM AUTHOR]

Polybutene‐1 (PB‐1) trigonal Form I crystals with different morphologies, namely spherulitic, hedritic, and fibrous, were used as seeds to quantitatively study the cross‐nucleation kinetics of the tetragonal Form II. Interestingly, a large difference in the cross‐nucleation ability of the various Form I seeds was observed. The Form I fiber exhibits the fastest cross‐nucleation, followed by the hedrite and eventually by the spherulite. The nucleation induction time was quantified from the evolution of the transmitted light intensity via polarized optical microscopy. The data were tested against different nucleation models, revealing that the rate‐determining step for nucleation is the growth of the nucleus to attain the critical dimension, rather than the formation of the first crystalline layer in contact with the substrate. In addition, for spherulitic seeds, a meaningful dependence of cross‐nucleation induction time on Form I lamellar thickness was found, with the kinetics being faster for higher original seed's crystallization temperatures. The results were interpreted assuming a free energy barrier for cross‐nucleation which is a function of the mismatch between the daughter and the parent polymorphs' lamellar dimensions. This aspect, together with the calculated low values of interfacial free energy difference parameter for nucleation, suggests the possible existence of an epitaxial relationships between cross‐nucleating PB‐1 Form II and Form I. [ABSTRACT FROM AUTHOR]

A semi-quantum secret sharing (SQSS) scheme based on Bell states is proposed in this paper. The sender who can perform any relevant quantum operations uses Bell states to share the secret keys with her participants that are limited to perform classical operations on the transmitted qubits. It is found that our scheme is easy to generalize from three parties to multiparty and more efficient than the previous schemes [Q. Li, W. H. Chan and D. Y. Long, Phys. Rev. A 82 (2010) 022303; L. Z. Li, D. W. Qiu and P. Mateus, J. Phys. A: Math. Theor. 26 (2013) 045304; C. Xie, L. Z. Li and D. W. Qiu, Int. J. Theor. Phys. 54 (2015) 3819]. [ABSTRACT FROM AUTHOR]

ABSTRACT Compared with the most stable crystalline form of isotactic polypropylene (α-iPP), β-iPP shows superior impact strength and high temperature performance, though the mechanism of how the frustrated structure of β-iPP is formed still remains unclear. In present work, the single crystal structure of a traditional β-iPP nucleating agent, N, N′-dicyclohexylterephthalamide (DCHT), was obtained for the first time and correlated with the epitaxial crystallization of β-iPP on the surface of DCHT crystal. The combination of synchrotron radiation X-ray microdiffraction and molecular chain packing model confirmed that a two dimensional match of chain-axis and inter-chain direction coexists between β-iPP (110) plane and DCHT (001) plane. It was further found that an epitaxial model is helpful to understand the formation of the frustrated structure of 31 helices packing in β-iPP. The molecular mechanics computation showed that as the (001) plane of DCHT is fixed, the packing mode of β-iPP (110) plane on the substrate surface is more stable than that of α-iPP (010) plane. This work clarifies the epitaxial crystallization mechanism of β-iPP on DCHT by employing both experimental and computational evidences. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 418-424 [ABSTRACT FROM AUTHOR]

Five new ring-intact limonoids with isomerized furan ring, chisosiamens A–E (1–5), along with four known compounds (6–9) were isolated from the fruit of Chisocheton siamensis Craib. Their structures were elucidated based on 1D and 2D NMR spectroscopic data, HRESIMS, circular dichroism, and exciton chirality method. The biological activities screening showed that new limonoid 5 exhibited significant NO inhibitory activity in LPS-activated RAW 264.7 macrophages (IC 50 : 10.13 ± 1.40 μM) and 1 , 2 , 5 , and 9 effectively reversed the resistance in MCF-7/DOX cells with the range IC 50 values of 10.20–15.06 μM (RI: 4.05–5.98). [Display omitted] • Nine limonoids from the fruit of Chisocheton siamensis craib. • Five new ring-intact limonoids with isomerized furan ring. • 5 exhibited significant NO inhibitory activity with IC 50 value of 10.13 μM. • 1 reversed resistance in MCF-7/DOX cells (IC 50 :10.20 μM, RI: 5.98). [ABSTRACT FROM AUTHOR]

• Plasma Apo-J levels are substantially elevated after ICH. • Plasma Apo-J levels are significantly correlated with GCS score and hematoma volume after ICH. • Plasma Apo-J is an independent predictor of 90-day poor outcome after ICH. • Plasma Apo-J may efficiently predict clinical outcome after ICH. Apolipoprotein J (Apo-J) may act as a neuroprotective factor after acute brain injury. We gauged plasma Apo-J concentrations in patients with acute intracerebral hemorrhage (ICH) and investigated its predictive value for 90-day outcome and disease severity. This prospective cohort study included 123 ICH patients and 123 healthy controls. The severity of ICH was assessed using the Glasgow Coma Scale (GCS) score and hematoma volume. Poor outcome was referred to as a Glasgow Outcome Scale (GOS) score of 1–3 at 90 days after stroke. Multivariate analysis was performed to identify associations of plasma Apo-J concentrations with disease severity and poor outcome. The plasma Apo-J concentrations of patients were significantly higher than those of healthy controls (median, 95.50 mg/l versus 55.71 mg/l; P < 0.001), and were independently correlated with hematoma volume (t = 2.716; P = 0.008) and GCS score (t = −5.978; P < 0.001). Plasma Apo-J significantly differentiated patients at risk of poor outcome (area under receiver operating characteristic curve (AUC), 0.772; 95% confidence interval (CI), 0.688–0.843; P < 0.001), and its predictive ability was similar to those of GCS score (AUC, 0.851; 95% CI, 0.776–0.909; P = 0.056) and hematoma volume (AUC, 0.849; 95% CI, 0.774–0.907, P = 0.089). Using maximum Youden index, plasma Apo-J concentrations >113.21 mg/l distinguished the development of poor outcome, with a sensitivity of 67.3% and a specificity of 87.3%. Plasma Apo-J concentrations >113.21 mg/l (odds ratio, 4.042; 95% CI, 1.093–14.951; P = 0.036) and hematoma volume (odds ratio, 1.124; 95% CI, 1.014–1.247; P = 0.027) were independently associated with poor outcome. Plasma Apo-J concentrations are markedly associated with disease severity and 90-day poor outcome in ICH patients. Hence, plasma Apo-J is presumed to be used as a potential prognostic biomarker of ICH. [ABSTRACT FROM AUTHOR]