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The most common tumor affecting the head and neck is head and neck squamous cell carcinoma (HNSCC). Characteristics of HNSCC include rapid onset, a lack of early diagnosis, drug resistance, relapse and systemic adverse effects, leading to inadequate prevention, diagnosis and treatment. Notably, previous research suggests that there is an association between S100 proteins and HNSCC. S100A8, S100A9 and S100A14 interfere with tumor cell proliferation by blocking the cell cycle. S100A4 enhances cancer stem cell properties, and interacts with actin and tropomyosin to promote tumor cell migration. S100A1, S100A8, S100A9, S100A10, S100A14 and S100P are involved in the occurrence and development of HNSCC via Hippo, nuclear factor κB, phosphatidylinositol kinase/protein kinase B/mammalian target of rapamycin and other signaling pathways. In addition, certain long non-coding RNAs (lncRNAs) and microRNAs are involved in regulating the expression of S100 proteins in HNSCC. Reducing the expression of certain members of the S100 protein family may improve the chemosensitivity of HNSCC. Collectively, these results suggested that S100 proteins may act as markers and targets for the prevention, diagnosis and treatment of HNSCC.

Bulk flow modeling of circumferentially grooved seals uses simplified physics models to predict leakage and rotordynamic coefficients more efficiently than full computational fluid dynamics (CFD) simulations, but at the expense of accuracy. Reducing bulk flow modeling inaccuracies, mainly a result of uncertainties in empirical quantities like friction factors and loss coefficients, requires a more fundamental and physical understanding of the flow features and their dependencies. This study utilizes CFD and an effective film thickness, a physical boundary between the jet and recirculating flows, to investigate Reynolds number effects on grooved seal flow fields and shear stresses. Simulations were run using ANSYS CFX for a single groove seal model assuming fully developed flow for a range of pressure differentials and rotor speeds. The effective film thickness boundary was defined by generating streamlines in the jet flow region that traversed the entire axial length of the model. Radial averaging across the local film thickness yielded bulk flow quantities used in processing and analysis. Flow structures, film thicknesses, shear stresses, and net flow expansion into the groove are found to be described completely by the ratio of circumferential to axial Reynolds number and the total resultant Reynolds number. Decreases in leakage with rotor speed are found to be dictated by increased land shear stresses and a decreased role of the groove at inducing pressure drop. An optimal groove aspect ratio between 0.07 and 0.19 is presented based on maximizing expanded film area while retaining a main groove recirculation region. This is the first paper to analyze circumferentially grooved seal flow from the standpoint of the effective film thickness, and by doing so, provides physical insight needed for a full description of the flow behavior. The results presented highlight bulk flow analysis areas where an effective film thickness approach could lead to new, physics motivated model development and the elimination of particular empirical coefficients. The effective film thickness approach thus provides a strong foundation on which substantial improvements in bulk flow modeling accuracy can be achieved.

Few drugs alleviate non-small cell lung cancer (NSCLC) metastasis effectively. Small molecular screening demonstrated that fangchinoline (Fan) reversed epithelial-mesenchymal transition (EMT) in NSCLC cells, inhibiting cell invasion and migration. RNA sequencing (RNA-seq) of Fan-treated NSCLC cells revealed that Fan potently quenched the NADP

A clear carryover effect of tree-ring formation was not detected based on a pulse-labelling experiment conducted on Juniperus communis in South Germany. The inherent linkage between photosynthesis and the formation of wood is important for the understanding of relationships between tree-ring series and climate/environmental data in dendroclimatology studies. However, it is impossible to reach a mechanistic procedure of tree stem radial growth depending on its carbon balance from a traditional statistical point of view alone. Pulse labelling experiment with stable carbon isotope (13CO2) has provided innovative insights into the fate of recently assimilated carbon in organs and carbon-containing compounds. In this study, we conducted an in situ pulse labelling experiment on 27 July 2016 to examine the response of tree ring and different-aged needles to short-term elevated 13CO2 of a juniper shrub growing on a heathland in South Germany. New and old needles from four expositions were sampled before and after the experiment. A wood segment was taken from the main branch and stable carbon isotope composition (δ13C) was analysed at an intra-annual time scale. Before the experiment, the mean δ13C was − 26.8 ± 0.4‰ (mean ± standard deviation) for both needle ages, while woody tissue showed about 3‰ higher δ13C compared to needles. Substantial enriched 13C was detected in the needles after the experiment. New needles showed significant higher δ13C than the old ones 1–7 days after the experiment. Significant enriched δ13C was detected in the wood from 35 to 61% of the annual tree ring in 2016, indicating that the short-term enrichment of 13C can affect wood formation for a large section. No enhancement in 13C signal appeared in the tree ring of the subsequent year 2017, suggesting the absence of a carryover effect. Wood formation did not reply on the carbohydrates stored even 1 year before and thus tree-ring ecophysiological modelling as well as dendrochronological studies should therefore benefit from such result.

A series of novel poly(amide-imide) (PAI) films with different amide contents were prepared from pyromellitic dianhydride and four amide-containing diamines. These PAI films exhibited excellent mechanical and thermal properties with tensile strength of 203.7–297.4 MPa and Tg above 407 °C. The rigid backbone structures combined with strong intermolecular interactions provided PAI films with ultralow in-plane CTE values from −4.17 ppm/°C to −0.39 ppm/°C in the temperature range of 30–300 °C. The correlation between thermal expansion behavior and aggregation structures of PAI film was investigated. The results suggested that hydrogen bonding interactions could be maintained even at high temperature, thus resulting in good dimension reversibility of films in multiple heating-cooling cycles. It is demonstrated that dimensional stabilities of PAI films are determined by the rigidity, orientation, and packing of molecular chains. Heat-resistant PAI films with ultralow CTE can be developed as flexible substrates by regulating backbones and aggregation structures for optoelectronic application.

The novel poly(amide imide) (PAI) films derived from three kinds of amide-containing diamines and different aromatic dianhydrides were synthesized and characterized. These PAI films exhibited excellent mechanical and thermal properties due to the rigidity of main chains and existence of strong hydrogen bonding interactions. For PAI films based on the diamine N,N′-(1,4-phenylene)bis(4-aminobenzamide) (PABA), their tensile strength and modulus even exceeded 280 MPa and 10 GPa, accompanied with Tg and T5 values higher than 408 °C and 520 °C, respectively. The results indicated that CTE values of these PAI films were greatly affected by rigidity, orientation and packing of chains as well as hydrogen bonding interactions. PABA-based PAI films with the highest amide content and linearly rigid backbones had ultralow in-plane CTE values ranging from −4.6 to −0.8 ppm/°C in the temperature range of 30–300 °C combined with the largest ∆n values of 0.22–0.23, suggesting a remarkable negative correlation between CTE and ∆n. The hydrogen bonding interactions were proved to be maintained at high temperature, and it was crucial for the regulation and control of thermal expansion. These heat-resistant PAI films with high tensile strength and ultralow CTE can be used as flexible polymeric substrates for optoelectronic application.

Considerable progress has been made in dendroclimatological research in China during the period 2000–2017, including a significant increase in the spatial coverage of tree-ring chronologies developed for paleoclimatic research. New tree-ring sampling sites have been established across the Tibetan Plateau, as well as the northeastern and sub-tropical eastern parts of China. Most of the studies use coniferous trees, although different plant functional types (e.g., broadleaf species and shrubs) have also been increasingly investigated. Tree-ring chronologies longer than 600 years, however, are mostly found on the Tibetan Plateau, with the longest one extending back to 2637 BCE (before Common Era). Most tree-ring records in the eastern parts of China are

We investigate the intra-annual growth patterns of Chinese pine in Helan Mountains, confirming that regional water status plays a dominated role in stem radial increment. The associations between environmental conditions and stem radial increment (SRI) are useful for assessing a species’ growth response to climate change. Intra-annual SRI dynamics of Chinese pine (Pinus tabulaeformis) were monitored half-hourly by automatic point dendrometer during the growing season (May–September) in 2016 and 2017 at two altitudes in the Helan Mountains, northern central China. Here, we compared the seasonal growth patterns between two altitudes and 2 years. Trees at low altitude are characterized by earlier cessation, shorter growing season, and lower growth rate, resulting in less annual growth, which may reflect the greater drought intensified by rising temperature at low altitude. June precipitation significantly affected tree growth rate. The xylem growth was active when daily mean air temperature was 9.9 °C at our study region for P. tabulaeformis in an arid environment. During the growing season, daily stem radial increment showed a significantly positive correlation with precipitation and a negative correlation with daily air temperature at all altitudes. Climatic variables associated with tree water status, namely precipitation, vapor pressure deficit, and relative humidity, played important roles in daily stem radial increment as the same result as a linear mixed model. These factors drive the complex physiological processes of stem radial increment by influencing the moisture available to the tree.

A series of novel semi-aromatic polyimides with low fluorine content were prepared from alicyclic dianhydrides, i.e. 1,2,4,5-cyclohexane-tetracarboxylic dianhydride (CHDA) and bicyclo[2.2.2]octa-7-ene-2,3,5,6-tetracarboxylic dianhydride (BCDA), and three aromatic diamines containing ortho-substituted methyl and pendent phenyl groups, respectively. These polyimides exhibited excellent solubility even though their fluorine content lower than 10 wt%. Chemical resistance to MEK and aqueous alkali of films was also satisfied for application as flexible substrates. The semi-aromatic polyimides showed outstanding heat resistance with Tg values up to 387 °C and good mechanical strength. These films had excellent optical transparency with cutoff wavelengths of 282–286 nm, transmittance >89% at 500 nm and yellowness indices

This study aims to validate the Chinese version of the Coma Recovery Scale-Revised (CRS-R).One hundred sixty-nine patients were assessed with both the CRS-R and the Glasgow Coma Scale (GCS), diagnosed as being in unresponsive wakefulness syndrome (UWS, formerly known as vegetative state), minimally conscious state (MCS), or emergence from MCS (EMCS). A subgroup of 50 patients has been assessed twice by the same rater, within 24 h. Patient outcome was documented six months after assessment.The internal consistency for the CRS-R total score was excellent (Cronbach's α = 0.84). Good test-retest reliability was obtained for CRS-R total score and subscale scores (intra-class correlation coefficient [ICC] = 0.87 and ICC = 0.66-0.84, respectively). Inter-rater reliability was high (ICC = 0.719; p 0.01). Concurrent validity was good between CRS-R total scale and GCS total scale. Diagnostic validity was excellent compared with GCS (emerged from UWS: 24%; emerged from MCS: 28%). When considering patient outcome, diagnostic validity was good. In addition, false-positive rates have been detected for both diagnoses.The Chinese version of the CRS-R is a reliable and sensitive tool and can discriminate patients in UWS, MCS, and EMCS successfully.

New insights into the intra-annual dynamics of tree-ring formation can improve our understanding of tree-growth response to environmental conditions at high-resolution time scales. Obtaining this information requires, however, a weekly monitoring of wood formation, sampling that is extremely time-intensive and scarcely feasible over vast areas. Estimating the timing of cambial and xylem differentiation by modeling thus represents an interesting alternative for obtaining this important information by other means. Temporal dynamics of cambial divisions can be extracted from the daily tree-ring growth rate computed by the Vaganov–Shashkin (VS) simulation model, assuming that cell production is tightly linked to tree-ring growth. Nonetheless, these predictions have yet to be compared with direct observations of wood development, i.e., via microcoring, over a long time span. We tested the performance of the VS model by comparing the observed and predicted timing of wood formation in black spruce [Picea mariana (Mill.)]. We obtained microcores over 15 years at 5 sites along a latitudinal gradient in Quebec (Canada). The measured variables included cell size and the timing of cell production and differentiation. We calibrated the VS model using daily temperature and precipitation recorded by weather stations located on each site. The predicted and observed timing of cambial and enlarging cells were highly correlated (R 2 = 0.8); nonetheless, we detected a systematic overestimation in the predicted timing of cambial cells, with predictions delayed by 1–20 days compared with observations. The growth rate of cell diameter was correlated with the predicted growth rate assigned to each cambial cell, confirming that cell diameter developmental dynamics have the potential to be inferred by the tree-ring growth curve of the VS model. Model performances decrease substantially in estimating the end of wood formation. The systematic errors suggest that the actual relationships implemented in the model are unable to explain the phenological events in autumn. The mismatch between the observed and predicted timing of wood formation in black spruce within our study area can be reduced by better adapting the VS model to wet sites, a context for which this model has been rarely used.

The mesoscopic simulation technique was applied to describe the phase separation behavior of polyimide blends and used for design of immiscible polyimide/BN blend films with enhanced thermal conductivity. The simulation equilibrium morphologies of different poly(amic acid) (PAA) blend systems were investigated and compared with optical images of corresponding polyimide blend films obtained by experiment. The immiscible polyimide blend films containing nano-/micro-sized BN with vertical double percolation structure were prepared. The result indicated that the thermal conductivity of polyimide blend film with 25 wt% nano-sized BN reached 1.16 W/(m·K), which was 236% increment compared with that of the homogenous film containing the same BN ratio. The significant enhancement in thermal conductivity was attributed to the good phase separation of polyimide matrix, which made the inorganic fillers selectively localized in one continuous phase with high packing density, consequently, forming the effective thermal conductive pathway.

A series of phenylethynyl-terminated oligoimides based on 2,3,3′,4′-biphenyltetracarboxylic dianhydride (a-BPDA), 2,2′-bis(trifluoromethyl)benzidine (TFDB), and bis( p-aminophenoxy)dimethyl silane (APDS) with different siloxane content and various calculated molecular weights were synthesized. The effect of siloxane structure on the processability of oligoimides and the thermal stability of cured polyimides (PIs) was investigated. The results indicated that the oligoimides have lower melt viscosity and broader processing window with the incorporation of flexible siloxane segment. The thermal stability of the cured PIs can be significantly enhanced by high-temperature postcuring due to the oxidative cross-linking of siloxane. The polyimide PI-s1-15 exhibited good balance between processability and thermal stability with the minimum melt viscosity of 0.4 Pa·s at 325°C and glass transition temperature as high as 470°C after postcuring at 450°C. The carbon fiber-reinforced composite T800/PI-s1-15 displayed excellent high-temperature performance, which gave the flexural strength and interlaminar shear strength of 703 and 33 MPa, respectively, when tested at the temperature as high as 450°C.

Knowledge of drought variability and their possible mechanisms during the past hundred years is still limited in the mountainous region of south-central Tibetan Plateau (TP). In this study, a long-term tree-ring width chronology dating back to 1190 CE was combined using 328 increment cores from the Nagqu region. Based on the relationships between this tree-ring width chronology and climate data, we reconstructed May–June self-calibrated Palmer Drought Severity Index (scPDSI) for the past 821 years (1190–2010 CE). Additional comparisons with other available precipitation or drought reconstructions were conducted. We further investigated the influence of the South Asian summer monsoon (SASM) on the drought variability in our study region. Results indicated that our tree-ring width chronology contained stable drought signal in the early summer season (May–June). During the past 821 years, the longest dry and wet periods lasted for 116 and 90 years, respectively, based on a 21-year Fast Fourier transform filter. Specifically, longer than ten years’ dry periods prevailed during 1211–1245 CE, 1280–1358, 1421–1471, 1500–1571, 1580–1598, 1650–1691, 1782–1807 and 1867–1982; while wet intervals occurred in 1190–1210 CE, 1246–1279, 1359–1420, 1472–1499, 1599–1649, 1692–1781, 1808–1866 and 1983–2010. Generally consistent dry and wet intervals across the southern TP were found by comparisons with other available datasets during their common periods. Interestingly, we detected an unstable influence of the SASM on the May–June drought variability in our study region, at least for the past three and a half centuries. This study therefore gives a new perspective of drought variability as well as their relationships with the SASM over a long-term period on the south-central TP.

The response of the growing season to the ongoing global warming has gained considerable attention. In particular, how and to which extent the growing season will change during this century is essential information for the Tibetan Plateau, where the observed warming trend has exceeded the global mean. In this study, the 1960–2014 mean length of the tree-ring growing season (LOS) on the Tibetan Plateau was derived from results of the Vaganov-Shashkin oscilloscope tree growth model, based on 20 composite study sites and more than 3000 trees. Bootstrap and partial correlations were used to evaluate the most significant climate factors determining the LOS in the study region. Based on this relationship, we predicted the future variability of the LOS under three emission scenarios (Representative Concentration Pathways (RCP) 2.6, 6.0, and 8.5, representing different concentrations of greenhouse gasses) derived from 17 Earth system models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5). The averaged LOS on the Tibetan Plateau is 103 days during the period 1960–2014, and April–September minimum temperature is the strongest factor controlling the LOS. We detected a general increase in the LOS over the twenty-first century under all the three selected scenarios. By the middle of this century, LOS will extend by about 3 to 4 weeks under the RCPs 2.6 and 6.0, and by more than 1 month (37 days) under the RCP 8.5, relative to the baseline period 1960–2014. From the middle to the end of the twenty-first century, LOS will further extend by about 3 to 4 weeks under the RCPs 6.0 and 8.5, respectively. Under the RCP 2.6 scenario, however, the extension reaches a plateau at around 2050 and about 2 weeks LOS extension. In total, we found an average rate of 2.1, 3.6, and 5.0 days decade−1 for the LOS extension from 2015 to 2100 under the RCPs 2.6, 6.0, and 8.5, respectively. However, such estimated LOS extensions may be offset by other ecological factors that were not included into the growth model. The estimated lengthening of the growing season could substantially affect carbon sequestration and forest productivity on the Tibetan Plateau.

Preclinical Research Osteoarthritis (OA) is a widely prevalent degenerative joint disease that severely impairs the health of the elderly population resulting in a heavy economic burden worldwide. Coenzyme Q10 (CoQ10) has shown anti-inflammatory effects in some diseases. The present study aimed to investigate if CoQ10 would suppress catabolic responses of interleukin (IL)-1β-induced chondrocytes. Rat chondrocytes were cultured and pretreated with CoQ10, and then stimulated with or without IL-1β (10 ng/ml). The expression and production of matrix metalloproteinase (MMP)-3, MMP-9, and MMP13 were determined using real-time PCR and Western blotting. CoQ10 suppressed MMP-3, MMP-9, and MMP13 production induced by IL-1β, and markedly inhibited IL-1β-induced MAPK pathways in rat chondrocytes. The present study provides insight into potential mechanisms by which CoQ10 protects against degeneration of cartilage in patients with OA, which may lead to new approaches for the treatment of OA.Drug Dev Res 78 : 403-410, 2017. © 2017 Wiley Periodicals, Inc.

Phenological responses of vegetation to climate, in particular to the ongoing warming trend, have received much attention. However, divergent results from the analyses of remote sensing data have been obtained for the Tibetan Plateau (TP), the world's largest high-elevation region. This study provides a perspective on vegetation phenology shifts during 1960-2014, gained using an innovative approach based on a well-validated, process-based, tree-ring growth model that is independent of temporal changes in technical properties and image quality of remote sensing products. Twenty composite site chronologies were analyzed, comprising about 3,000 trees from forested areas across the TP. We found that the start of the growing season (SOS) has advanced, on average, by 0.28 d/y over the period 1960-2014. The end of the growing season (EOS) has been delayed, by an estimated 0.33 d/y during 1982-2014. No significant changes in SOS or EOS were observed during 1960-1981. April-June and August-September minimum temperatures are the main climatic drivers for SOS and EOS, respectively. An increase of 1 °C in April-June minimum temperature shifted the dates of xylem phenology by 6 to 7 d, lengthening the period of tree-ring formation. This study extends the chronology of TP phenology farther back in time and reconciles the disparate views on SOS derived from remote sensing data. Scaling up this analysis may improve understanding of climate change effects and related phenological and plant productivity on a global scale.

Response of climate warming on tree-ring formation has attracted much attention during recent years. However, most studies are based on statistical analysis, lacking understanding of tree-physiological processes, especially in the mountainous regions of the Tibetan Plateau (TP). Herein, we firstly use an updated new version of the tree-ring process-based Vaganov-Shashkin model (VS-oscilloscope) to simulate tree-ring formation and its relationships with climate factors during the past six decades. Our analyses covered 341 sampled trees growing within elevations ranging from 2750 to 4575 m a.s.l. at five sampling sites across the TP. Simulated tree-ring width series are significantly (p

To compensate for an extremely heavy journal, jacking pockets can be added to the surface of pads in fluid film bearings. Jacking pockets can range in size and shape and will have an influence on the hydrodynamic performance of the bearing. Computational fluid dynamics (CFD) was used to better understand the influence of the geometry of a rectangular/stadium-shaped, jacking pocket on the performance of bearings. First, the influence of the pocket depth on the pressure profile of the bearing was investigated. A varying profile occurred with jacking pocket depths less than 6.6 × Cb. After this threshold, the pocket depth ceased to have an influence on the pressure profile. A second study examined the circumferential length of the pocket, and the pressure profile was found to approach the smooth case as the pocket circumferential length decreased. Response surface models were created to map the influence of the jacking pocket geometry on the journal location in the bearing, power loss, and stiffness characteristics of the bearing. This is the first study on influence of the geometry of a jacking pocket on the operation and linear stiffnesses of the bearing in fluid film journal bearings.

Objective: To detect the initiation of swallowing in patients with disorders of consciousness (DOC) as well as the relationship between the initiation of swallowing and the prognosis of DOC patients. Methods: Nineteen DOC patients were included in this study, and a self-controlled trial compared five different stimuli. The five different stimuli were as follows: (1) one command, as recommended by the Coma Recovery Scale-Revised (CRS-R), which was "open your mouth"; (2) placing a spoon in front of the patient's mouth without a command; (3) placing a spoon filled with water in front of the patient's mouth without a command; (4) one command-"there is a spoon; open your mouth"-with a spoon in front of the patient's mouth; (5) one command, "there is a spoon with water; open your mouth," with a spoon filled with water in front of the patient's mouth. All 19 patients were given these five stimuli randomly, and any one of the commands was presented four times to a patient, one at a time, at 15-s intervals. The sensitivity and specificity of the initiation of swallowing in detecting conscious awareness were determined. Results: None of the patients responded to the first four stimuli. However, six patients showed initiated swallowing toward the fifth stimulus. Among those six, five patients showed improvement in their consciousness state 6 months later. The sensitivity and specificity of the initiation of swallowing for DOC patients was 83.33% [95% CIs (36%, 100%)] and 92.31% [95% CIs (64%, 100%)], respectively. Conclusions: The initiation of swallowing can be an early indication of conscious behavior and can likely provide evidence of conscious awareness. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT03508336; Date of registration: 2018/4/16.

Fluid film bearings for turbomachinery are designed to support the loads applied by the rotor system. Oil-lubricated bearings are widely used in high speed rotating machines. However, environmental issues and risk-averse operations have made water lubricated bearings increasingly popular. Due to different viscosity properties between oil and water, the low viscosity of water decreases film thickness significantly. Crowning and tapers are two main ways to maintain the film thickness requirements in water lubrication, but no studies about the influence of these parameters on the film thickness in water-lubricated bearings have been reported. Therefore, further understanding of the performance associated with optimizing the bearing design with different weighted performance and their relationships to bearing design variables could be invaluable to bearing design engineers. This study explores the impact of three crowning and taper design variables on the performance of one tilting pad thrust bearing using the design of experiments techniques applied to a thermoelastohydrodynamic (TEHD) bearing model. The bearing design variables analyzed in this study include the radius of the ground-in crown, taper circumferential angle offset, and the vertical taper distance at the inner and outer radii. Each of the design variables is first varied over five levels, each in central composite design. The outputs from the TEHD numerical simulations used as performance measures for each bearing design point were the minimum film thickness, the film thickness at the pivot location, maximum film pressure and power loss. Multi-objective optimization was performed. A range of weighting parameters was selected for the optimization function to find a bearing design that maintains the minimum film thickness criterion while minimizing power loss. The resulting optimum design points allowed for a comparison between the design optimization at different weightings. This study demonstrates how designers can use these approaches to view the relationships between design variables and important performance metrics to design better bearing for a wide range of applications.

Carbon fiber reinforced thermosetting polyimide (CF/TSPI) composites were interleaved with thermally stable thermoplastic polyimide (TPPI) fiber veils in order to improve the interlaminar fracture toughness without sacrificing the heat resistance. Both of the mode I and mode II interlaminar fracture toughness (GIC and GIIC) for the untoughened laminate and TPPI fiber veils interleaved laminates were characterized by the double cantilever beam (DCB) test and end notch flexure (ENF) test, respectively. It is found that the TPPI fiber veils interleaved laminates exhibit extremely increased fracture toughness than the untoughened one. Moreover, the areal density of TPPI greatly affected the fracture toughness of laminates. A maximum improvement up to 179% and 132% on GIC and GIIC is obtained for 15 gsm fiber veils interleaved laminate, which contributes to the existence of bicontinuous TPPI/TSPI structure in the interlayer according to the fractography analysis. The interlaminar fracture behavior at elevated temperatures for 15 gsm fiber veils interleaved laminate were also investigated. The results indicated that the introduction of thermally stable TPPI fiber veils could enhance the fracture toughness of CF/TSPI composites by exceeding 200% as compared to the untoughened one even as tested at 250 °C.

The influence of turbulence and convective fluid inertia in a water-lubricated journal bearing was investigated using two types of models: a “conventional” solution based on traditional lubrication theory (Reynolds equation) and a more rigorous computational fluid dynamics (CFD) program containing a full Navier-Stokes solution. The calculations reveal that turbulence accounts for around 50% of the load capacity in the water-lubricated bearing studied, highlighting the importance of accurate characterization of turbulence in such applications. Convective inertia, also referred to as transport inertia because it depends only on the spatial parameters within the film rather than time-dependent journal motions, was found to lower the static film pressures (load capacity) by about 6% compared to an inertialess solution.Hydrodynamic pressures calculated by the conventional Reynolds solution were initially about 30% lower than those of the more rigorous CFD model for the water-lubricated bearing operatin...

Cambial activity of ~100-year-old Qilian juniper trees initiated before the middle of May at an elevation of 3200 m a.s.l.; June and July were the main stem radial increment period. Around the middle of August, all xylem cell differentiation periods are completed. Precipitation or relative humidity is the main limiting factor for tree radial growth on the northeastern Tibetan Plateau. Previous studies have found that annual tree-ring width series of Qilian juniper (Sabina przewalskii Kom.) in the northeastern Tibetan Plateau (TP) are mostly moisture controlled, irrespective of site elevation. Knowing precisely the cambial growth dynamics during a vegetation period can lead to a better understanding of the climatic factors driving regional tree growth patterns. We observed wood formation with micro-cores taken at weekly intervals from late April to early October 2013, and monitored daily stem radial changes with high-resolution electronic point dendrometers in 30-min intervals. Dormant cambium contained 5–6 cell layers in the cambium zone. Cambial activity initiated before the middle of May in all the monitored trees. About three quarters of the total cell production or radial growth formed during June and July. Lignification of secondary walls of new xylem cells continued from end of May to middle of August. After the middle of August, the cambium entered into the inactive period. Dendrometer measurements confirmed that June and July were the main stem radial increment period. Nonparametric Kendall’s Tau correlations indicate that daily relative humidity and precipitation significantly influence stem growth in May. No obvious relationships were detected in June. In July, significant negative influences of maximum temperature and positive effects of relative humidity prevailed. Overall, growing season precipitation or associated relative humidity is the limiting factor for tree stem radial increments on the intra-annual scale. Our results present a thorough understanding of Qilian juniper xylogenesis and its climate forcing within the whole growing season on the northeastern TP.

A series of 4-phenylethnylphthalic anhydride (PEPA)-terminated oligoimides were prepared by co-oligomerizing isomeric dianhydrides, i.e., 2,3,3&prime, 4&prime, biphenyltetracarboxylic dianhydride (a-BPDA), 2,3,3&prime, benzophenonetetracarboxylic dianhydride (a-BTDA) or 2,3,3&prime, diphenylethertetracarboxylic dianhydride (a-ODPA), with diamines mixture of bis(4-aminophenoxy)dimethyl silane (APDS) and 2,2&prime, bis(trifluoromethyl) benzidine (TFDB). The effects of siloxane content and dianhydride structure on the rheological properties of these oligoimides and thermal stability of the corresponding cured polyimide resins were investigated. The results indicated that the introduction of the siloxane structure improved the melt processability of the oligoimides, while the thermal stability of the cured polyimide resins reduced. The oligoimide derived from a-ODPA revealed better melt processability and melt stability due to the existence of a flexible dianhydride structure. The oligoimide PIS-O10 derived from a-ODPA gave the lowest minimum melt viscosity of 0.09 Pa&middot, s at 333 &deg, C and showed the excellent melt stability at 260 &deg, C for 2 h with the melt viscosity in the range of 0.69&ndash, 1.63 Pa&middot, s. It is also noted that the thermal stability of these resins can be further enhanced by postcuring at 400&ndash, 450 &deg, C, which is attributed to the almost complete chemical crosslinking of the phenyethynyl combined with oxidative crosslinking of siloxane. The PIS-T10 and PIS-O10 resins that were based on a-BTDA and a-ODPA, respectively, even showed a glass transition temperature over 550 &deg, C after postcuring at 450 &deg, C for 1 h.

A thrust bearing is a particular type of rotary bearing permitting rotation between parts but designed to support a predominately axial load. Part I of this study was submitted to ASME 5th Joint US-European Fluids Engineering Summer Meeting. It compared the experimental, TEHD and CFD results for a thrust bearing. Reasonable relative errors between these three results were observed. The outlet oil film thickness at low speeds and the inlet oil film thickness at high speeds as calculated using TEHD were found to be more accurate than their counterparts. Isothermal, non-deforming CFD was found to predict outlet film thickness accurately as thermal deformation has a lower impact in the outlet region. Isothermal and non-deforming CFD was also found to produce a qualitatively accurate film thickness and pressure distribution. Experimental data from a second paper reported by the same authors in Part I, provides temperature measurements in two different pads and showed some variation of temperature from pad to pad. A thermal CFD, different from isothermal CFD in Part I, was performed in this Part II. Different data analysis methods will be included in Part II including a comparison of leading edge, mid-plane and trailing edge temperature at two loads, two speeds. 24 different speed-load combination TEHD cases and 12 CFD cases were run in Part II in addition to the 32 TEHD cases and 8 CFD cases in Part I. Both TEHD and CFD underpredict the slope between temperature and shaft speeds. TEHD also underpredicts the slope between temperature and bearing loads while CFD can get an accurate slope between temperature and bearing loads. An improved inlet temperature model would fix the error between temperature and bearing load in CFD, and also can enable CFD to have the same accuracy as TEHD analysis for the temperature versus shaft speed relation. The inlet film thickness from both TEHD and CFD is underestimated. TEHD is more accurate than CFD in outlet film thickness, or minimum film thickness, which is a critical performance characteristic in fluid film thrust bearings. While CFD is more accurate than TEHD in inlet film thickness and power loss.

Precise knowledge how tree growth will respond to future climate change is essential for the adapted management of forest ecosystems. By conducting sensitivity tests, tree-ring process-based cambial growth models can provide an innovative way to better understand wood formation under different climate change scenarios. As a case study in semi-arid north central China, we used artificially increased or decreased daily climatic data as input to the Vaganov-Shashkin dynamic growth model to investigate the response of wood formation to climatic change. By calibrating the tree-ring model using daily climate data over the period 1951–2010, we found that 81% of radial growth was driven by soil moisture, while 13% of growth was controlled by temperature. During the main growing season June–August, significant differences in the integral growth rate occurred after changing precipitation by ± 30% or by decreasing temperature by 3.0 °C (p

Bearings are machine elements that allow components to move with respect to each other. A thrust bearing is a particular type of rotary bearing permitting rotation between parts but designed to support a predominately axial load. Oil-lubricated bearings are widely used in high speed rotating machines such as those found in the aerospace and automotive industries. With the increase of velocity, the lubrication regime will go through boundary lubrication, mixed lubrication, and hydrodynamic lubrication (full film). In this paper, the analysis was in the hydrodynamic lubrication region. THRUST is used to predict the steady-state operating characteristics of oil-lubricated thrust bearings. As a thermoelastohydrodynamic prediction tool, THRUST assumes a 3D turbulence model, 3D energy equation, and 2D Reynolds equation. Turbulence is included by obtaining average values of eddy momentum flux (Reynolds stress) and averaging the influence down to a 2D Reynolds equation. Convergence is achieved by iterating on the pad tilt angles and pivot film thickness until the integrated pressure matches the load applied to the pad. Despite the multiple experimental, CFD, and TEHD studies of thrust bearings that have been performed to date, no validation has yet been performed to confirm the accuracy of TEHD methods in modeling the performance of thrust bearings by both experimental and advanced computational means simultaneously. This study addresses this need by comparing TEHD and CFD simulation results of film thickness, temperature, power loss, and pressure in thrust bearings taken from the literature at multiple speeds and loads with results from experimental data. Starting from the case of the lowest speed and load, it was verified that this case is indeed laminar and with negligible thermal and elastic effects. Four cases were run in THRUST, a TEHD solver, combining thermal and deformation in each rotational speed and load combination. Additionally, a CFD study was performed in ANSYS CFX with the assumptions of isothermal, non-deforming. The average viscosity from THRUST was used in CFD to follow the effects of the isoviscous assumption. Then, the experimental, TEHD and CFD results were compared at each case. Experimental, TEHD, and CFD results show acceptable agreement when turbulence is negligible.

Preclinical Research Osteoarthritis (OA) is a widely prevalent degenerative joint disease that severely impairs the health of the elderly population resulting in a heavy economic burden worldwide. Coenzyme Q10 (CoQ10) has shown anti-inflammatory effects in some diseases. The present study aimed to investigate if CoQ10 would suppress catabolic responses of interleukin (IL)-1β-induced chondrocytes. Rat chondrocytes were cultured and pretreated with CoQ10, and then stimulated with or without IL-1β (10 ng/ml). The expression and production of matrix metalloproteinase (MMP)-3, MMP-9, and MMP13 were determined using real-time PCR and Western blotting. CoQ10 suppressed MMP-3, MMP-9, and MMP13 production induced by IL-1β, and markedly inhibited IL-1β-induced MAPK pathways in rat chondrocytes. The present study provides insight into potential mechanisms by which CoQ10 protects against degeneration of cartilage in patients with OA, which may lead to new approaches for the treatment of OA.Drug Dev Res 78 : 403-410, 2017. © 2017 Wiley Periodicals, Inc.

Background: Misdiagnosis rate is high in patients with disorders of consciousness, potentially leading to an inappropriate clinical management of these patients. Sensitive standardised rating scales offer some protections from these diagnostic errors. In this context, the use of the Coma Recovery Scale-Revised (CRS-R) has strongly been recommended by the American Congress of Rehabilitation Medicine. Objective: Here, we present the work that has been performed to translate this important diagnostic tool in Chinese. Methods: The scale has been translated from its original English version to Chinese by a team of native Chinese speakers in agreement with an expert highly trained in the use of the original version of the CRS-R and, then, back-translated to English by four independent translators blinded to the original version. The resulting translation has been sent to the original author for final approval. Results and conclusion: The Chinese version of the CRS-R is now available for use in clinical practise. Further investigations will nevertheless be needed in order to show that its psychometric properties are identical to the original English version.

The northern fringe of the Asian summer monsoon region (NASM) in China refers to the most northwestern extent of the Asian summer monsoon. Understanding the characteristics and underlying mechanisms of drought variability at long and short time-scales in the NASM region is of great importance, because present and future water shortages are of great concern. Here, we used newly developed and existing tree-ring, historical documentary and instrumental data available for the region to identify spatial and temporal patterns, and possible mechanisms of drought variability, over the past two millennia. We found that drought variations were roughly consistent in the western (the Qilian Mountains and Hexi Corridor) and eastern (the Great Bend of the Yellow River, referred to as GBYR) parts of the NASM on decadal to centennial timescales. We also identified the spatial extent of typical multi-decadal GBYR drought events based on historical dryness/wetness data and the Monsoon Asia Drought Atlas. It was found that the two periods of drought, in AD 1625–1644 and 1975–1999, exhibited similar patterns: specifically, a wet west and a dry east in the NASM. Spatial characteristics of wetness and dryness were also broadly similar over these two periods, such that when drought occurred in the Karakoram Mountains, western Tianshan Mountains, the Pamirs, Mongolia, most of East Asia, the eastern Himalayas and Southeast Asia, a wet climate dominated in most parts of the Indian subcontinent. We suggest that the warm temperature anomalies in the tropical Pacific might have been mainly responsible for the recent 1975–1999 drought. Possible causes of the drought of 1625–1644 were the combined effects of the weakened Asian summer monsoon and an associated southward shift of the Pacific Intertropical Convergence Zone. These changes occurred due to a combination of Tibetan Plateau cooling together with more general Northern Hemisphere cooling, rather than being solely due to changes in the sea surface temperature of the tropical Pacific. Our results provide a benchmark for comparing and validating paleo-simulations from general circulation model of the variability of the Asian summer monsoon at decadal to centennial timescales.

The recent unprecedented warming found in different regions has aroused much attention in the past years. How temperature has really changed on the Tibetan Plateau (TP) remains unknown since very limited high-resolution temperature series can be found over this region, where large areas of snow and ice exist. Herein, we develop two Juniperus tibetica Kom. tree-ring width chronologies from different elevations. We found that the two tree-ring series only share high-frequency variability. Correlation, response function and partial correlation analysis indicate that prior year annual (January–December) minimum temperature is most responsible for the higher belt juniper radial growth, while more or less precipitation signal is contained by the tree-ring width chronology at the lower belt and is thus excluded from further analysis. The tree growth-climate model accounted for 40 % of the total variance in actual temperature during the common period 1957–2010. The detected temperature signal is further robustly verified by other results. Consequently, a six century long annual minimum temperature history was firstly recovered for the Yushu region, central TP. Interestingly, the rapid warming trend during the past five decades is identified as a significant cold phase in the context of the past 600 years. The recovered temperature series reflects low-frequency variability consistent with other temperature reconstructions over the whole TP region. Furthermore, the present recovered temperature series is associated with the Asian monsoon strength on decadal to multidecadal scales over the past 600 years.

We present two tree-ring chronologies for the southeastern Tibetan Plateau (TP), established by applying the signal-free regional curve standardization and standard dendrochronological methodologies to a set of ring-width series of Tibetan juniper. The relationship between tree growth and climate shows that temperature variability in the previous year is the primary factor controlling tree growth at the upper portion of the forest belt. Accordingly, we developed a mean annual temperature reconstruction covering the period A.D. 984–2009 and explaining 50 % of the instrumental variance. The spatial correlation patterns suggest that our temperature reconstruction is a reasonable proxy for temperature change over the TP. At long time scales, the temperature reconstruction shows similar warm-cold patterns to those in temperature records from other regions of the TP, indicating that decadal and multidecadal temperature variations were generally synchronous across the TP during the past millennium. The periods 1140–1350 and 1600–1800 were common warm and cold episodes over the TP, respectively. Comparison of our reconstruction with four Northern Hemisphere (NH) temperature series indicates that temperature changes on the southeastern TP have generally followed the NH temperature patterns during the past millennium. Our results also suggest that temperature variability over the TP is affected by the Atlantic Multidecadal Oscillation (AMO), with the warm (cool) phases of the AMO associated with above-average (below-average) temperatures over the TP.

The southern Tibetan Plateau forms the ecotone between forest areas and alpine steppes and thus, tree growth is expect to react sensitive to climate variability in this semi-humid region. We sampled 328 increment cores from 169 trees at two study sites at four elevations along altitudinal transects from 4,000 to 4,500 m a.s.l. to evaluate elevation-dependent tree growth–climate relationships of Juniperus tibetica. Standard dendrochronological statistical parameters like mean inter-series correlation (Rbar), expressed population signal as well as signal-to-noise ratio is not significantly correlated to elevation. Mean segment lengths and average growth rates of the tree-ring series increase with elevation. Correlation and response function analysis with available climate data indicate that elevation has no significant effect on tree growth–climate relationships. Instead, local tree growth is mainly driven by common regional climatic signals as it is also indicated by significant correlations between all chronologies over their common period of A.D. 1550–2010. Moisture variability during April–June has the highest impact on tree growth, even close to the upper tree limit.

In the National Natural Reserve of the Qilian Mountains, northwest China, automated dendrometers were installed on Qilian juniper (Sabina przewalskii Kom.) in 2010. Here, we present a complete 1-year data series of dendrometer measurements and synchronous meteorological records. The mean daily radius change index curve obtained by first-difference standardization was analyzed. The results indicate strong similarities of stem radius variations among the studied trees. By graphical inspection of sub-diurnal shrinkage and expansion patterns, seasonal stem radius variations could be divided into two general phases. During early winter to spring, daily amplitudes show strong fluctuations, and meteorological data indicate that both air and soil temperatures are positively related to stem radius swelling. From late March to early November 2011, stem radius expansion is negatively related to both air and soil temperatures, as well as to vapor pressure deficit, and positively related to precipitation and soil moisture. We found that the dividing lines between the two phases were strongly linked to the occurrence of a 0 °C daily mean air temperature, indicating that air temperature played an important effect on stem radius variations in this cold and arid environment. During the growing season in 2011, May and June are the most productive months.

Rotordynamic predictions on machines supported by fluid film bearings typically rely on models that solve the Reynolds equation to determine the bearing dynamics. The Reynolds equation is derived from the thin film momentum equation that assumes fluid inertia terms can be totally neglected because the reduced Reynolds number is very small. This paper examines the impact of including temporal fluid inertia on tilting pad bearings that are widely used in the applications of concern. Using the small perturbation method, a new form of the perturbed equation is developed for easy application to tilting pad journal bearings. The temporal fluid inertia leads to a set of full added mass coefficients and modifications to the damping coefficients. When applied to a typical 5-pad, tilting pad bearing, it is found that the influence of temporal inertia increases with the increase of shaft whirl frequency. Its impact is also dependent on the magnitude of the added mass coefficients relative to the magnitudes of its stiffness and damping. Therefore, temporal fluid inertia effects could be important for high speed, light rotor applications, as well as applications using low viscosity fluids, such as water.

During full-load, full-speed string testing of a compressor train, its gearbox pinion experienced high radial vibrations at a particular frequency that was well below the gear mesh frequency, but which was excited by the pinion’s harmonics at 9× , 10× or 11× running speed. To identify the vibrations’ root cause, a coupled lateral, torsional, and axial analysis was performed on the gearbox’s two testing configurations: its no-load, uncoupled mechanical run test, and the string test. Results indicate that the vibrations likely were caused by a resonance situation involving the alignment of two highly amplified natural frequencies: the pinion’s fifth lateral mode, and a torsional-lateral mode of the pinion and its adjacent coupling. Contrary to all known published discussions of similar problems, the vibrations were not likely associated with the pinion’s heavily damped, fourth lateral mode. Modeling and analysis recommendations include aspects not typically considered in gearbox applications, such as the need for higher fidelity rotor and coupling models and the inclusion of pad/pivot radial dynamics.