Thermal History of Rocks in the Shiwandashan Basin, Southern China: Evidence from Apatite Fission Track Analysis

Based on interpretations of the apatite fission track analysis data for 10 outcrop samples and forward modeling of confined fission track length distributions, the thermal history of rocks in the Shiwandashan basin and its adjacent area, southern China, has been qualitatively and semi quantitatively studied. The results reflect several features of the thermal history. Firstly, all the samples have experienced temperatures higher than 60-70 ℃. Secondly, the time that the basement strata (T 1 b ) on the northwestern side of the Shiwandashan basin were uplifted and exhumed to the unannealed upper crust (with a paleogeotemperature of below 60-70 ℃) is much earlier than the basement rocks ( γ 1 5) on the southeastern side of the basin. Thirdly, the thermal history of samples from the basin can be divided into six stages, i.e., the fast burial and heating stage (220-145 Ma), the transient cooling stage (145-135 Ma), the burial and heating stage (135-70 Ma), the rapid cooling stage (70-50 Ma), the relatively stable stage (50-20 Ma) and another rapid cooling stage (20 Ma to present).

NOVEL METHOD FOR ERROR ANALYSIS AND SELF-CALIBRATION OF LASER TRACKING MIRROR MECHANISM

Laser tracking system （LTS） is an advanced device for large size 3D coordinates measuring with the advantages of broad range, high speed and high accuracy. However, its measuring accuracy is highly dominated by the geometric errors of the tracking mirror mechanism. Proper calibration of LTS is essential prior to the use of it for metrology. A kinematics model that describes not only the motion but also the geometric variations of LTS is developed. Through error analysis of the proposed model, it is claimed that gimbals axis misalignments and tracking mirror center off-set are the key contributors to measuring errors of LTS. A self-calibration method is presented of calibrating LTS with planar constraints. Various calibration strategies utilizing single-plane and multiple-plane constraints are proposed for different situations. For each calibration strategy, issues about the error parameter estimation of LTS are exploded to find out in which conditions these parameters can be uniquely estimated. Moreover, these conditions reveal the applicability of the planar constraints to LTS self-calibration. Intensive studies have been made to check validity of the theoretical results. The results show that the measuring accuracy of LTS has increased by 5 times since this technique for calibration is used.

Apatite Fission Track Evidence of Uplift Cooling in the Qiangtang Basin and Constraints on the Tibetan Plateau Uplift

The Qiangtang basin is located in the central Tibetan Plateau. This basin has an important structural position, and further study of its tectonic and thermal histories has great significance for understanding the evolution of the Tibetan Plateau and the hydrocarbon potential of marine carbonates in the basin. This study focuses on low temperature thermochronology and in particular conducted apatite fission track analysis. Under constraints provided by the geological background, the thermal history in different tectonic units is characterized by the degree of annealing of samples, and the timing of major （uplift-erosion related） cooling episodes is inferred. The cooling history in the Qiangtang basin can be divided into two distinct episodes. The first stage is mainly from the late Early Cretaceous to the Late Cretaceous （69.8 Ma to 108.7 Ma）, while the second is mainly from the Middle- Late Eocene to the late Miocene （10.3 Ma to 44.4 Ma）. The first cooling episode records the uplift of strata in the central Qiangtang basin caused by continued convergent extrusion after the Bangong- Nujiang ocean closed. The second episode can be further divided into three periods, which are respectively 10.3 Ma, 22.6-26.1 Ma and 30.8-44.4 Ma. The late Oligocene-early Miocene （22.6-26.1 Ma） is the main cooling period. The distribution and times of the earlier uplift-related cooling show that the effect of extrusion after the collision between Eurasian plate and India plate obviously influenced the Qiangtang basin at 44.4 Ma. The Qiangtang basin underwent compression and started to be uplifted from the middle-late Eocene to the early Oligocene （45.0-30.8 Ma）. Subsequently, a large-scale and intensive uplift process occurred during the late Oligocene to early Miocene （26.1-22.6 Ma） and the basin continued to undergo compression and uplift up to the late Miocene （10.3 Ma）. Thus, uplift-erosion in the Qiangtang basin was intensive from 44.5 Ma to about 10 Ma. The timing of cooling in the second episode shows that the uplift of the Qiangtang basin was caused by the strong compression after the collision of the Indian plate and Eurasian plate. On the whole, the new apatite fission-track data from the Qiangtang basin show that the Tibetan Plateau started to extrude and uplift during 45-30.8 Ma. The main period of uplift and formation of the Tibetan Plateau took place about 22.6-26.1 Ma, and uplift and extrusion continued until the late Miocene （10.3 Ma）.

Real-time lane departure warning system based on principal component analysis of grayscale distribution and risk evaluation model

A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and then each search bar was tracked using Kalman filter between frames. The lane detection performance was evaluated and demonstrated in ways of receiver operating characteristic, dice similarity coefficient and real-time performance. For lane departure detection, a lane departure risk evaluation model based on lasting time and frequency was effectively executed on the ARM-based platform. Experimental results indicate that the algorithm generates satisfactory lane detection results under different traffic and lighting conditions, and the proposed warning mechanism sends effective warning signals, avoiding most false warning.

Proteomics of serum exosomes identified fibulin-1 as a novel biomarker for mild cognitive impairment

Mild cognitive impairment(MCI)is a prodrome of Alzheimer’s disease pathology.Cognitive impairment patients often have a delayed diagnosis because there are no early symptoms or conventional diagnostic methods.Exosomes play a vital role in cell-to-cell communications and can act as promising biomarkers in diagnosing diseases.This study was designed to identify serum exosomal candidate proteins that may play roles in diagnosing MCI.Mass spectrometry coupled with tandem mass tag approach-based non-targeted proteomics was used to show the differentially expressed proteins in exosomes between MCI patients and healthy controls,and these differential proteins were validated using immunoblot and enzyme-linked immunosorbent assays.Correlation of cognitive performance with the serum exosomal protein level was determined.Nanoparticle tracking analysis suggested that there was a higher serum exosome concentration and smaller exosome diameter in individuals with MCI compared with healthy controls.We identified 69 exosomal proteins that were differentially expressed between MCI patients and healthy controls using mass spectrometry analysis.Thirty-nine exosomal proteins were upregulated in MCI patients compared with those in control patients.Exosomal fibulin-1,with an area under the curve value of 0.81,may be a biomarker for an MCI diagnosis.The exosomal protein signature from MCI patients reflected the cell adhesion molecule category.In particular,higher exosomal fibulin-1 levels correlated with lower cognitive performance.Thus,this study revealed that exosomal fibulin-1 is a promising biomarker for diagnosing MCI.

Novel electrospun poly(ε-caprolactone)/type Ⅰ collagen nanofiber conduits for repair of peripheral nerve injury

Recent studies have shown the potential of artificially synthesized conduits in the repair of peripheral nerve injury. Natural biopolymers have received much attention because of their biocompatibility. To investigate the effects of novel electrospun absorbable poly(ε-caprolactone)/type Ⅰ collagen nanofiber conduits(biopolymer nanofiber conduits) on the repair of peripheral nerve injury, we bridged 10-mm-long sciatic nerve defects with electrospun absorbable biopolymer nanofiber conduits, poly(ε-caprolactone) or silicone conduits in Sprague-Dawley rats. Rat neurologica1 function was weekly evaluated using sciatic function index within8 weeks after repair. Eight weeks after repair, sciatic nerve myelin sheaths and axon morphology were observed by osmium tetroxide staining, hematoxylin-eosin staining, and transmission electron microscopy.S-100(Schwann cell marker) and CD4(inflammatory marker) immunoreactivities in sciatic nerve were detected by immunohistochemistry. In rats subjected to repair with electrospun absorbable biopolymer nanofiber conduits, no serious inflammatory reactions were observed in rat hind limbs, the morphology of myelin sheaths in the injured sciatic nerve was close to normal. CD4 immunoreactivity was obviously weaker in rats subjected to repair with electrospun absorbable biopolymer nanofiber conduits than in those subjected to repair with poly(ε-caprolactone) or silicone. Rats subjected to repair with electrospun absorbable biopolymer nanofiber conduits tended to have greater sciatic nerve function recovery than those receiving poly(ε-caprolactone) or silicone repair. These results suggest that electrospun absorbable poly(ε-caprolactone)/type Ⅰ collagen nanofiber conduits have the potential of repairing sciatic nerve defects and exhibit good biocompatibility. All experimental procedures were approved by Institutional Animal Care and Use Committee of Taichung Veteran General Hospital, Taiwan, China(La-1031218) on October 2, 2014.

Formation and stability of ultrasonic generated bulk nanobubbles

Although various and unique properties of bulk nanobubbles have drawn researchers'attention over the last few years,their formation and stabilization mechanism has remained unsolved.In this paper,we use ultrasonic methods to produce bulk nanobubbles in the pure water and give a comprehensive study on the bulk nanobubbles properties and generation.The ultrasonic wave gives rise to constant oscillation in water where positive and negative pressure appears alternately.With the induced cavitation and presence of dissolved air,the bulk nanobubbles formed."Nanosight"(which is a special instrument that combines dynamic light scattering with nanoparticle tracking analysis)was used to analyze the track and concentration of nanobubbles.Our results show that in our experiment,sufficient bulk nanobubbles were generated and we have proven they are not contaminations.We also found nanobubbles in the ultrasonic water change in both size and concentration with ultrasonic time.

Measurement and characterization of bulk nanobubbles by nanoparticle tracking analysis method

The size of the bulk nanobubbles(typically 100 nm-200 nm in diameter)is below the optical resolution of the typical microscopes,which makes it difficult to make a direct observation of them and differentiate between the nanoparticles and the nanobubbles.In this work,a nanoparticle tracking analysis(NTA)system is developed for tracking and sizing the bulk nanobubbles,and more broadly,the Brownian diffusing particles.We demonstrate the capabilities of the NTA in characterizing the nanoparticles through systematic validation of accuracy and resolution.We particularly exhibit its unique advantages in detecting the polydisperse nanoparticle populations.Then the nucleation and the thermodynamic stability of the bulk nanobubbles are systematically studied by the NTA system.The bulk nanobubbles smaller than 600 nm in size are generated via the ultrasonication method.It is shown that both the ultrasonic cavitation treatment time and amplitude,essentially,the energy input,favor the nucleation of the bulk nanobubbles with a more concentrated size distribution,a higher concentration,and a smaller hydrodynamic size.The temperature dependence of the bulk nanobubbles over a wide range from 25°C to 70°C is explored.It is found that the nanobubble first shrinks in size significantly and then the size keeps approximately constant with the increasing temperature,showing a narrow size distribution.The transition temperature is around 45°C.Further,as an open system,the NTA is a potential tool in the study of the dynamic behavior of the bulk nanobubbles in situ,such as the coalescence and the collapse.

Seasonal and inter-annual variations of Arctic cyclones and their linkage with Arctic sea ice and atmospheric teleconnections

The seasonal and inter-annual variations of Arctic cyclone are investigated. An automatic cyclone tracking algorithm developed by University of Reading was applied on the basis of European Center for Medium-range Weather Forecasts（ECMWF） ERA-interim mean sea level pressure field with 6 h interval for 34 a period. The maximum number of the Arctic cyclones is counted in winter, and the minimum is in spring not in summer.About 50% of Arctic cyclones in summer generated from south of 70°N, moving into the Arctic. The number of Arctic cyclones has large inter-annual and seasonal variabilities, but no significant linear trend is detected for the period 1979–2012. The spatial distribution and linear trends of the Arctic cyclones track density show that the cyclone activity extent is the widest in summer with significant increasing trend in CRU（central Russia）subregion, and the largest track density is in winter with decreasing trend in the same subregion. The linear regressions between the cyclone track density and large-scale indices for the same period and pre-period sea ice area indices show that Arctic cyclone activities are closely linked to large-scale atmospheric circulations, such as Arctic Oscillation（AO）, North Atlantic Oscillation（NAO） and Pacific-North American Pattern（PNA）. Moreover,the pre-period sea ice area is significantly associated with the cyclone activities in some regions.

STATISTICAL ANALYSIS OF CYCLONE TRACKS IN WESTERN ANTARCTIC REGION

The paper shows the statistical analysis of cyclone tracks that have influence on the western Antarctic region.Based on the conditions of cyclone movement and its impact upon the weather,cyclone tracks are classified into three categories,i.e.,the track moving towards the northern tip of the Antarctic Peninsula, southern track,and northern track. Moreover,in this paper,the frequency distributions of cyclone tracks,the major tracks with higher frequencies,the original region of Antarctic cyclones and the seasonal features of Antarctic cyclones have been analyzed.The results show that there are higher cyclogeneses in summer,whereas relatively fewer cycloge- neses in winter,and cyclone numbers in transitional seasons are close to the climatological average.The analysis also shows that the moving velocity of Antarctic cyclone is about the same in winter and summer. It obviously speed up during the transitional season.

ANALYSIS OF PERIODIC CHARACTERISTICS OF ERRATIC TRACK FREQUENCY FOR TYPHOON IN SOUTH CHINA SEA AND WEST PACIFIC

Typhoons with erratic movement are studied for their annual frequency of occurrence over the South China Sea and Northwest Pacific,based on 102 years of data (1884—1985).It discovers that the years with higher fre- quency tend to get together.There are well-defined periods of 12 and 30 years,revealed with the maximum entropy method (MEM),the latter of low-frequency oscillation being clearer.

Elastic-plastic seismic response of CRTS II slab ballastless track system on high-speed railway bridges

China railways track structure II (CRTS II) slab ballastless track on bridge is one kind of track structures unique to China. Its main bearing component of longitudinal force is the continuous base plate rather than rail. And the track-bridge interaction is weakened by the sliding layer installed between base plate and bridge deck. In order to study the dynamic response of CRTS II slab ballastless track on bridge under seismic action, a 3D nonlinear dynamic model for simply-supported bridges and CRTS II track was established, which considered structures such as steel rail, fasteners, track plate, mortar layer, base plate, sliding layer, bridge, consolidation, anchors, stoppers, etc. Then its force and deformation features under different intensities of seismic excitation were studied. As revealed, the seismic response of the system increases with the increase of seismic intensity. The peak stresses of rail, track plate and base plate all occur at the abutment or anchors. Both track plate and base plate are about to crack. Besides, the rapid relative displacement between base plate and bridge deck due to the small friction coefficient of sliding layer is beneficial to improve the seismic performance of the system. During the earthquake, a large vertical displacement appears in base plate which leads to frequent collisions between stoppers and base plate, as a result, stoppers may be damaged.

Employing nanoparticle tracking analysis of salivary neuronal exosomes for early detection of neurodegenerative diseases

Neurodegenerative diseases are a set of progressive and currently incurable diseases that are primarily caused by neuron degeneration.Neurodegenerative diseases often lead to cognitive impairment and dyskinesias.It is now well recognized that molecular events precede the onset of clinical symptoms by years.Over the past decade,intensive research attempts have been aimed at the early diagnosis of these diseases.Recently,exosomes have been shown to play a pivotal role in the occurrence and progression of many diseases including cancer and neurodegenerative diseases.Additionally,because exosomes can cross the blood-brain barrier,they may serve as a diagnostic tool for neural dysfunction.In this review,we detail the mechanisms and current challenges of these diseases,briefly review the role of exosomes in the progression of neurodegenerative diseases,and propose a novel strategy based on salivary neuronal exosomes and nanoparticle tracking analysis that could be employed for screening the early onset of neurodegenerative diseases.

Biogeographical affinities and evolution of terrestrial fauna in the Qinghai-Tibetan Plateau and the Himalayas:a case study of Aphidomorpha

The history of the Qinghai-Tibetan Plateau and the Himalayas(QTPH)region makes it a‘living laboratory'for understanding how the Earth's abiotic evolution has shaped regional biotas.However,no studies to date have attempted to investigate general macro-scale biogeographical patterns and biogeographical affinities of the QTPH terrestrial fauna in a global context.Based on the analyses of the global distributions of QTPH Aphidomorpha species,we examined generalized distribution patterns for them and investigated the biogeographical affinities between the QTPH and other regions.Track analysis and cluster analysis of the global distributions of 298 Aphidomorpha species in the QTPH identified seven generalized biogeographical tracks and eight general distribution patterns.Both approaches detected similarly generalized distribution patterns.Four marginal areas where the generalized tracks intersect,i.e.the eastern Himalayas,the western Himalayas,the Hengduan Mountains,and the northeastern QTPH,were identified as biogeographical nodes.The generalized distribution patterns indicate the biogeographical affinities between the QTPH and other regions and suggest the complex nature of the QTPH fauna.A spatial congruence between the nodes and diversity centres detected by previous studies indicates the four marginal areas have been key areas in fauna evolution as centres for faunal exchange as well as glacial refugia.Based on the biogeographical patterns,the geological history of the QTPH and the evolutionary history of Aphidomorpha,we propose an evolutionary scenario for the evolution of the QTPH aphid fauna in which faunal exchanges,vicariance due to the uplift of geographical barriers,environmental heterogeneity and Quarternary glaciations have shaped the diversity patterns and fauna in the QTPH.

Timing of uplift and evolution of the Lüliang Mountains,North China Craton

This study analyses evidence for reformed basin development and basin-mountain coupling associated with devel- opment of the Ordos Basin and the Laliang Mountains, China. Gaining an improved understanding of the timing and nature of uplift and evolution of the Ltiliang Mountains is important for the reconstruction of the eastern sedimentary boundary of the Ordos Basin （a major petroliferous basin） as well as for providing insight into the evolution and breakup of the North China Craton （NCC）. Based on systematic sampling for fission track analysis, it is suggested that the main phase of uplift of the Laliang Mountains occurred since later part of the Early Cretaceous. Three evolutionary stages of uplift and development are identified： slow initial uplift （120-65 Ma）, accelerated uplift （65-23 Ma）, and intensive uplift （23 Ma to present）, with the ma- jority of the uplift activity having occurred during the Cenozoic. The history of uplift is non-equilibrium and exhibits complex- ity in temporal and spatial aspects. The middle and northern parts of the Ltiliang Mountains were uplifted earlier than the southern part. The most intensive episode of uplift activity commenced in the Miocene and was associated with a genetic cou- pling relationship with the eastern neighboring Cenozoic Shanxi Grabens. The uplifting and evolutionary processes of the Ltiliang Mountains area since later part of the Early Cretaceous share a unified regional geodynamic setting, which was ac- companied by uplift of the Mesozoic Ordos Basin and development of the neighboring Cenozoic Shanxi Grabens. Collectively, this regional orogenic activity is related principally to the far-field effects of both the compression sourced from the south- western Tibet Plateau and westward subduction of the Pacific Plate in Cenozoic.

Extracellular vesicles and reproduction-promotion of successful pregnancy

Extracellular vesicles （EVs） are membrane-bound complexes secreted from cells under both physiological and pathological conditions. They contain proteins, nucleic acids and lipids and act as messengers for cell-cell communication and signalling, particularly between immune cells. EV research is a rapidly evolving and expanding field, and it appears that all biological fluids contain very large numbers of EVs; they are produced from all cells that have been studied to date, and are known to have roles in several reproductive processes. This review analyses the evidence for the role of EVs throughout human reproduction, starting with the paternal and maternal gametes, followed by the establishment and continuation of successful pregnancies, with specific focus, where possible, on the interaction of EVs with the maternal immune system. Importantly, variations within the EV populations are identified in various reproductive disorders, such as pre-term labour and pre-eclampsia.

Light scattering:A review of particle characterization applications

This review covers the progress of light scattering applications in the field of particle characterization in the past decade. The review addresses static light scattering （the measurement of scattering intensities due to light-particle interaction at various spatial locations）, dynamic light scattering （the measurement of scattering due to light-particle interaction as a function of time）, and scattering tracking analysis （the tracking of particle movement through scattering measurement）.