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The physical properties of fabric causing an uncomfortable tactile perception under certain clothing pressure has always been a difficult problem in the field of fabric comfort research. According to a large number of works in the literature, the amygdala was recognized as the key brain region for negative perceived emotions. In order to investigate the fabric factors causing the signal changes in the amygdala brain region, functional magnetic resonance imaging was used to monitor the amygdala brain region and its anatomical sub-brain region under the same degree of compression stimulation from several different corsets, and the percent signal changes (PSCs) were extracted and analyzed. The results showed that there was a significant positive correlation between the PSCs of the centromedial group of the amygdala and the average dynamic friction coefficient (MIU) of the fabric at the level of 0.05, and a general linear model was established ( R2 = 0.998, p = 0.019). These results indicated that the surface friction properties of the fabric successfully attracted the attention of the central amygdala, and the attention increased linearly with the increase of MIU. This finding not only laid a foundation for exploring the brain perception mechanism of fabric discomfort, but also provides a possibility for further quantification of fabric discomfort perception by using the amygdala brain region.

The integration of high conductive networks and textiles has become a favorable technical route to fulfill the objectives of wearable electronics. Herein, high stretchable and recoverable PET fabric coated with a layer of silver nanowire network by a simple and scalable polyol-method is provided. The electrothermal performance, resistance temperature-sensitivity, electromagnetic shielding performance, strain sensing, and washability of silver nanowire (AgNWs)/PET fabrics with different coating times were performed. The conductivity of the fabric coated AgNWs of 2.8 mg/cm2 is as high as 175 S/m, the EMI shielding effectiveness is 37 dB, and it gives a highly sensitive strain response to human movement (gauge factor of −6.16 under 10% strain) and an underwater oil repellent angle of 125°. The heating temperature can reach above 100°C within 27 s under an applied current of 0.10 A. In addition, an excellent linearity of the resistance temperature-sensitive behavior for AgNWs/PET fabrics is obtained, and fabric Ag-5 gives a negative temperature coefficient of resistance (TCR) of −0.05%/°C. Knitted fabric with multi-function is obtained by use of silver nanowire coating. This method provides a simple, low-cost and easy-to-scalable process for the production of electronic textiles, such as fabric heater, microwave blocker, sensor, and other technologies.

In the Northwest Loess Plateau of China that is full of mountains and deep valleys, high-filled cut-and-cover tunnels (HFCCTs) not only satisfy transportation demands, but they create usable land as well. Several studies have been conducted to investigate the feasibility of HFCCTs, but the time-dependent behavior of the significant backfill needed for HFCCTs has not been adequately examined. Settlement can be severely underestimated due to the time-dependent behavior of ultra-high backfill, and the earth pressure becomes redistributed accordingly. Therefore, the ability to predict the long-term behavior of backfill on HFCCTs is necessary to ensure the long-term safety of the structure. Using a discrete element method (DEM), the changes in vertical earth pressure (VEP), vertical displacement, and load transfer mechanisms above an HFCCT were investigated in this study under scenarios with and without considering backfill creep. The results show that the differential displacement of the soil and the surface settlement obviously increase due to creep and the subsequent cycles of primary and secondary consolidation. Moreover, the stress surrounding the HFCCT is redistributed, causing both the stress concentration and slope effect to weaken over time, but the VEP increases significantly. The micromechanical parameters also change correspondingly. Our results clearly show that the creep of high backfill soil must be considered carefully in HFCCT projects to ensure structural safety.

It was well known that the human body would produce an uncomfortable sensation when the fabric exerted a certain amount of pressure irritation on the skin. The amygdala had long been thought to be the source of negative emotion perception. However, up to now, the brain signal changes in the amygdala evoked by skin exposure pressure had not been known.In this work, a series of gradually increasing contact pressure stimulus from boneless corsets was repeatedly applied to the body's waist and abdomen, and the technology of functional magnetic resonance imaging (fMRI) was adopted to detect the brain response synchronously.The results shown that both subjective comfort score and percent signal changes (PSCs) of amygdala decreased with the increase of skin contact pressure. When the skin pressure applied to the waist and abdomen of the human body exceeded about 1 kPa, blood oxygen level dependent signal in the amygdala was negatively activated. Besides, the degree of response of PSCs was intense than subjective evaluation, and the standard deviations of PSCs between individuals were much smaller than subjective evaluations.It was suggested that skin contact pressure stimulus caused the attention of the amygdala brain area. The greater the stimulus, the higher the attention, but such attention was caused by negative activation of the amygdala induced by skin discomfort. In addition, skin comfort representation based on brain perception was superior to subjective representation due to its higher response sensitivity and antipsychological interference ability.

To solve the problem of the low accuracy of the traditional qualitative method for highway asphalt pavement performance, a prediction model based on improved firefly algorithm (IFA)-support vector machine (SVM) is established by combining SVM theory and IFA. First, firefly field search is introduced into the prediction model to overcome the random movement of fireflies with the increase in the number of iterations in the optimization process. Second, in the subsequent optimization process, the dynamic adjustment algorithm is used to search the step size to balance the global search ability, which accelerates the optimization selection of the performance parameters of the SVM model. Finally, the example is verified and compared with the standard FA-SVM prediction method to verify the validity of the IFA-SVM model and the feasibility of prediction accuracy. The result shows the following: (1) The maximum relative error is 2.5435% and the minimum is 0.8206% when the standard FA-SVM is used to predict the pavement performance of the Baiyin section of the G6 expressway. The maximum relative error is 1.0858% and the minimum is 0.3654%, and their root mean square error is smaller than that of the standard FA-SVM method. (2) The IFA-SVM model has a faster convergence rate and a higher accuracy than the standard FA-SVM when predicting the performance of asphalt pavement on highways. The prediction result is not only closer to the measured value but also provides effective support for the maintenance decision of asphalt pavement on highways.

Known as the super fiber of the twenty-first century, poly-p-phenylenebenzobisoxazole (PBO) fibers exhibit outstanding strength and modulus, fire and heat resistance, which are superior to those of poly-p-phenylene terephthalamide fiber. However, the poor resistance of acid corrosion is regarded as a fatal weakness, which restricts its application in complicated chemical environment. In present work, PBO fibers were exposed in strong acid solutions under different conditions, and then, surface morphology was observed by optical microscopy and scanning electron microscopy. Substantial changes in functional groups were investigated by Fourier-transform infrared (FTIR) spectroscopy, as well as changes in crystalline structure using differential scanning calorimetry (DSC) and thermal stability using thermogravimetric analysis (TGA). After treatment by H2SO4 and HNO3 solution, the strength of the fibers declines typically, while the modulus increases. It is attributed to the formation of N–H bonds in the vicinity of 3410.0 cm−1 confirmed by FTIR spectra. Hydrogen bonds, derived from N–H bonds, increase the thermal degradation temperature from 716.4 °C (untreated) to 725.6 °C (treated by H2SO4), shown in TGA curves. HNO3 treatment is more destructive than that of H2SO4. There exist longitudinal corrosion cracks after treatment by HNO3 solution. Furthermore, HNO3 solution penetrates into crystalline region and destroys the ordered crystal structure of PBO fibers demonstrated by DSC results.

Wrinkling is one of the most common flaws of woven fabrics in domestic use and industrial applications. It is necessary to develop an objective evaluation method to quantify the smoothness appearance of fabrics effectively. Herein, a fabric multi-deformation tester (FMDT) was designed to evaluate the smoothness appearance of garment fabrics by one sequential mechanical test, overcoming the main difficulties of the existing visual measurement methods for wrinkling evaluation of fabrics with complex colors and patterns. The k-means clustering algorithm was used to objectively cluster the fabric samples based on the characteristic parameters, including the wrinkle-induced residual force ( F wr), hysteresis distance ( H fr), position deflection ( D fr) and stretching recovery slope ( S tr), from the testing curve and the thickness and weight of fabrics, and comparisons with subjective evaluation were also conducted. The results reveal that the k-means clustering is able to classify the smoothness appearance of fabrics using the selected characteristic parameters, showing a good consistency with the subjective clustering results. The feasibility of using the mechanical and deformation properties of textiles to characterize fabric smoothness appearance is proved, and the FMDT provides a potential method to analyze the wrinkling of fibrous materials in a convenient way.

High-filled cut-and-cover tunnels (HFCCTs) can be used in northwestern China to reclaim usable land. Because of the ultra-high backfill used in HFCCTs, the stress on the cut-and-cover tunnel (CCT) will change. However, The calculation method adopted at present for earth pressure usually result in either overestimation or underestimation. Different from vertical earth pressure, lateral earth pressure (LEP) can help stabilize the structure of HFCCTs. The current methods for estimating LEP rely mainly on Rankine’s theory or empirical formulas. Using conventional methods has led to errors between actual values and estimated values, and such deviation increases with an increase in the backfill height over the CCT. Due to the complex soil-arching effect, the current methods used for calculating LEP for HFCCTs need to be modified. These modifications need to consider characteristics of the CCT, mechanical properties of the backfill soil, and the geometry of the landform. In this work, several influential factors were identified through numerical analysis using the finite element method and propose four corresponding coefficients of modification: k0, the cross-sectional shape of the CCT; k1, the mechanical properties of the backfill; k2, the width of the CCT; and k3, the coupled effect of the slope angle and ratio of the width of the valley floor to the width of the CCT. Because current methods and specifications may overestimate the LEP for HFCCTs in valleys, a general equation was formulated for modifying the LEP coefficient. Also, this general modification equation was verified that agrees well with the numerical analysis results for different cases.

The high-filled cut-and-cover tunnel (HFCCT) is a solution to reclaim more useable lands due to the unique landforms of Loess Plateau in northwestern China. Because of the ultrahigh backfill, the estimation of vertical earth pressure will significantly affect the design and safety of the cut-and-cover tunnel (CCT). The current methods for estimating the vertical earth pressure are either to overestimate or underestimate the vertical earth pressure on the top of HFCCT. To more precisely estimate the vertical earth pressure distribution, the vertical earth pressure based on the soil column pressure,γh(h: the height of backfill above the CCT), needs to be properly modified. Considering different influential factors, four corresponding coefficients are proposed:k0: cross-sectional shape of CCT effect,k1: stiffness of backfill effect,k2: width of CCT effect, andk3: coupling effect of slope angle,θ,and the ratio of B/D. It is found thatk0has little influence; thek3andk1reduce andk2amplifies theγh. The corresponding general forms for these coefficients are determined based on finite element analysis results. A general equation for estimating vertical earth pressure for the HFCCT including these four coefficients is proposed. Meanwhile, this general form is verified by the numerical analysis results and experimental results for different cases. Therefore, this proposed equation is applicable to estimate the vertical earth pressure for existing or newly designed HFCCT. Furthermore, this proposed method can significantly reduce the computational work in engineering analysis.

We used finite element analysis to study the impacts of cross-sectional shape, elasticity modulus, hole width, slope angle, and ratio of trench width to tunnel width on the vertical earth pressure on top of cut-and-cover tunnels. The study results show that the effect of the tunnel width coefficient nonlinearly increases with increase in the fill height. The effect of the elasticity modulus coefficient and the coupled effect of slope angle and the ratio of trench width to cut-and-cover tunnel width decreases nonlinearly. We also analyzed two calculation cases for high-filled railway cut-and-cover tunnels and compared the calculated results with those obtained by numerical simulation.

The tactile perception of fabric surface properties in the brain has always been a major research issue in the study of the contact comfort of fabrics. This study introduced the concept of PSC (percent signal change) obtained by fMRI (functional Magnetic Resonance Imaging) technology to explore the perceptual brain regions concerned with the roughness of the fabric surface. Firstly, the PSCs of human somatosensory cortexes, including the SI (primary somatosensory cortex) and SII (secondary somatosensory cortex), under the stimulation of boneless corsets with different surface roughness, were extracted and analyzed. As the surface roughness of the fabric increased gradually from smooth to rough, the brain region in which the maximum PSC occurred gradually transited from the SI to the SII, which indicated that the SI brain region paid more attention to the contact of smooth fabrics, while the SII brain region laid emphasis on the fine tactile perception of rough fabrics. Furthermore, the result of sub-regions in the SI and SII showed that, with the increase of the roughness of the fabric surface, the PSC of the OP2 (Operculum Parietal 2) brain region increased significantly, and the brain region concerned with the fabric surface tactile stimulation was gradually transferred from the slow adaptive sensory projection Brain Area 3a in the SI to the fast adaptive sensory projection Brain Area 1 in the SI, and finally moved to OP2 in the deep cortex of the SII.

Different sensations are generated when we touch textiles with different performance. The mechanical properties related to fabric touch have been studied for a long time, the relationship between which and the subjective feelings is well understood. However, the cognitive mechanism of our brain on the tactile perception evoked by fabric touch were rarely studied. The relationship between mechanical properties of fabrics and the brain response in different areas is the vacancy of the study but urgent problem. In our previous study, the advanced technology of fMRI was proved to be an effective tool for detecting brain response evoked by tactile stimulation of fabric touch with high spatial resolution. Now in this study, further fMRI experiments were conducted to observe brain response when participants touched different fabrics using their fingers in a specified way, and the most widely recognized functional atlas, Brodmann’s area maps, were applied to locate the cortical activations in functional areas. Activations in the participants’s brain in different Brodmann areas was compared with the mechanical preperties of the fabric samples tested by the instruments of KES-FB. The results showed that activation information in the participants’ brain can distinguish the fabric samples very well. Activations in several Brodmann areas are closely connected with different tactile preperties of the fabrics. Therefore, Brodmann’s area maps were proved to be a useful functional atlas for cortical localization of tactile perception evoked by fabric touch.

Planar frequency selective surface (FSS) fabrics with grids, strips or patches by simple methods of patching, embroidery, clipping and carving were fabricated. The periodic structures, laminated structures, processing method and materials pertaining to the electromagnetic shielding behaviors were investigated. Firstly, equivalent circuit and electromagnetic (EM) shielding behavior of basic frequency selective structure units and complex fretwork structure were provided, involving the decoupling of complex fretwork structure. In addition, various laminating structures of SPs and SGs were determined, one of superposition of SPs and SGs provides a SE peak of 40.2 dB (average SE of 25.1 dB in the whole frequency domain), the other presents a SE peak of 27.1 dB (average SE of 19.1 dB in the whole frequency regime). Furthermore, tunable selective electromagnetic shielding by a simple mechanical way was provided, which can realize a tunable SE peak varying from 730 MHz to 1580 MHz. This work might provide a perspective for the assemble and analytical approximation of FSS fabrics for scientists and engineers in this cross-disciplinary field.

Fabric hand is most frequently used by consumers and researchers to evaluate the touch feeling of textiles. Academically, many methods have been developed to characterize it psychologically and physically, and the relationship between the hand attributes of fabrics and their physical properties are well understood. However, in physiological terms, the cognitive mechanism of the brain on different attributes of fabric hand is not clear. Previous studies have shown that the sensory or discrimination information from fabric touch can be detected by the technology of functional magnetic resonance imaging (fMRI). In this study, further fMRI experiments were carried out, attempting to find the relationship between the cerebral cortices of various brain areas and different hand attributes of fabrics. The subtle atlas of Automated Anatomical Labeling (AAL) was used to display and analyze the blood oxygenation level dependent signals completely and conveniently. The results showed that when the subjects touched two samples with distinct fabric hand in a specified way, activation information and the index of the mean signal in every related brain areas can distinguish them, and several brain regions in the AAL atlas are linked to different fabric hand attributes. The technology of fMRI was proved again to be a promising tool for studying the cognitive mechanism of the brain on fabric touch.

Minggu Zhu,1,* Qicai Wang,2,* Zhaowen Luo,1 Kelong Liu,2 Zhiqiao Zhang1 1Department of Internal Medicine, The Affiliated Chencun Hospital of Shunde Hospital, Southern Medical University, Shunde District, Guangdong, China; 2Department of General Surgery, The Affiliated Chencun Hospital of Shunde Hospital, Southern Medical University, Shunde District, Guangdong, China *These authors contributed equally to this work Background: As a serious challenge for public health, the prognosis of gastric cancer patients is still poor. The current study aimed to develop and validate a prognostic signature to predict the overall survival of gastric cancer patients.Patients and methods: The dataset in the present study was obtained from The Cancer Genome Atlas database. The present study finally included 343 gastric cancer patients with information on long non-coding RNA (lncRNA) expression and overall survival.Results: A prognostic model named Eleven-lncRNA signature was constructed according to the expression values of eleven prognostic lncRNA predictors identified by univariate and multivariate Cox regression model. According to time-dependent receiver operating characteristic curves, the Harrell’s concordance indexes of Eleven-lncRNA signature were 0.764 (95% CI 0.720–0.808), 0.776 (95% CI 0.732–0.820), and 0.807 (95% CI 0.763–0.851) for 1-year overall survival, 3-year overall survival, and 5-year overall survival respectively in the model group. In the validation group, the Harrell’s concordance indexes of Eleven-lncRNA signature were 0.748 (95% CI 0.704–0.792), 0.794 (95% CI 0.750–0.838), and 0.798 (95% CI 0.754–0.842) for 1-year overall survival, 3-year overall survival, and 5-year overall survival respectively. The gastric cancer patients (n=343) in the model group could be stratified into low-risk group (n=171) and high-risk group (n=172) according to the median of Eleven-lncRNA signature score. Kaplan–Meier survival curves showed that the mortality rate in the high-risk group was significantly poorer than that in the low-risk group (P

High-filled cut-and-cover tunnels (HFCCTs) are common in northwestern China because their construction allows usable land over the CCT to be reclaimed. However, due to the unique landforms...

Background It is now well understood that, as an uncomfortable sensation evoked by special fabric, prickle derives from the mechanical stimulation of protruding hairiness from fabric surface against the human skin, in which some nociceptors are easy to be triggered by stiff fiber ends. However, up to now, the neural mechanism of the brain for perceiving fabric-evoked prickle is still unclear. Materials and methods In this work, A type of single-fiber stimulus made from nylon filament was used to repetitively prick the skin of volar forearm at a specific frequency, and the technology of functional magnetic resonance imaging (fMRI) was adopted to detect the brain response synchronously. Results The results show that repetitive prickling stimulation from the single fiber applied to the volar forearm aroused distributed activation in several brain regions, such as primary somatosensory cortex, secondary somatosensory cortex, motor cortex, bilateral occipital lobe, insular cortex, and ipsilateral limbic lobe. Although the brain activation distribution is similar to pain, the single fiber-evoked prickle sensation possesses unique activation characteristics in several brain regions. Conclusion It is suggested that the sensation evoked by cutaneous prickling stimulation from single fiber belongs to a kind of multidimensional experience involving somatosensory, motor, emotional, cognitive, etc Our study constitutes an important step toward identifying the brain mechanism of fabric-evoked prickle.

High-filled cut-and-cover tunnels (HFCCTs) can be used to reclaim usable land due to the unique landforms in western China. The load reduction methods used to reduce the earth pressure on ...

Inter-city railway as the city’s comprehensive transportation system, the development of urban industrial economy and the image of the overall improve greatly boost. However, scientific and reasonable forecast traffic is the focus on the study of the inter-city railway construction project, which aim is to obtain the characteristics and rules of passenger flow, planning area to provide comprehensive system for railway planning and the actual resources and foundation of real and reliable data. Based on the grey relational analysis method influence the traffic data and the relationship between influencing factors, choose the main influence factors of traffic influence factors of the BP neural network model is established. Finally combined Lanzhou to Zhongchuan Airport inter-city railway project to traffic prediction research and survey data, it is concluded that the influence factors of the BP neural network model has good predictability to the traffic.

The thermal conductivity of concrete was investigated under the unsaturated condition during early curing. Based on the improved steady-state method, the thermal conductivity of unsaturated concrete at different ages under curing at the constant temperature of 20 ℃, 5 ℃, and −5 ℃ was tested. The influences of the water-binder ratio, initial air content, fly ash content, curing age, and curing temperature on the thermal conductivity of concrete were analyzed. The water-binder ratio, initial air content, fly ash content, curing age, and curing temperature are inversely proportional to the thermal conductivity of early age concrete. Through the analysis of the correlation between these factors and the thermal conductivity, the correlation between various factors and the thermal conductivity of concrete from large to small is as follows: curing temperature, initial air content, curing age, water-binder ratio, fly ash content. A multiple regression prediction time-varying model with acceptable accuracy is proposed to ensure the accuracy of the effective thermal conductivity prediction.

The present study was carried out with a new approach to evaluating the comfort of fabric contact pressure. Functional magnetic resonance imaging technology was conducted to monitor brain response when a comfortable fabric contact pressure, according to the subjective evaluation, was applied to the skin surface of the lower human chest. After a strict method of calibration with a family-wise error check analysis, the study we performed revealed the right secondary somatosensory cortex appeared prominently positively activated under a comfortable fabric pressure state. This suggested the secondary somatosensory cortex brain region, particularly the right secondary somatosensory cortex, was probably the characteristic brain region for fabric comfort perception. A reasonable explanation was that proper contact pressure facilitated the serial information flow from the primary somatosensory cortex to the secondary somatosensory cortex, and comfortable touch stimulated the firing of A-beta afferent nerves.

Bottle-recycled polyethylene terephthalate (R-PET) fibers were fabricated by the melt spinning method. Based on characteristics of R-PET chips, this study involved a primary exploration of the spinning parameters, including spinning temperature, spinning speed and spinneret plate. The properties of R-PET and original PET (O-PET) fibers were compared using scanning electron microscopy (SEM), tensile testing, sonic orientation, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR). Apparent morphological observation displays an irregular cross-sectional shape and a scattered diameter distribution for R-PET fibers. Compared with O-PET fibers, R-PET fibers demonstrate a greater breaking strength and smaller elongation at break, resulting from the lower crystallinity and higher degree of orientation. Furthermore, the R-PET fibers have the same chemical structure as that of O-PET fibers demonstrated by FTIR spectroscopy, but TGA results show that thermal stability of R-PET fibers is significantly inferior to that of O-PET fibers, as a result of too many impurities and oligomers during the recycling process.

In previous studies, nano-silica (NS) can improve the concrete performances under the conventional curing condition (about 20 °C). However, because more and more engineering projects are constructed in cold regions, it is very important to study the performances of concrete, which is cured under the negative-temperature condition. In order to explore whether NS still has the positive effect on concrete cured under the negative-temperature condition, multi-scale experiments were conducted to investigate the influence of NS on the performances (mechanics, resistance to chloride ion penetration (RCP) ability, pore characteristics, microstructure, and hydration products) of the concrete cured under the condition of −3 °C. The results indicate that the negative-temperature curing condition is not conducive to the formation of compressive strength for concrete. Under the curing condition of −3 °C, the cement paste and the interface transition zone are deteriorated by the addition of NS, which reduces the compressive strength of concrete. In addition, as the increase of the NS content added into the concrete under the curing condition of −3 °C, the compressive strength, the RCP ability, and the amount of calcium hydroxide generated decrease, and the coarsening of pore structure increases.