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Purpose: Previous studies on the seismic response of the site were carried out under isothermal conditions and homogeneous foundations, but there were few studies on the seismic response of the layered site under thermal effect. However, since the coupling effect between temperature and stress–strain affects the wave propagation, and natural soil usually exists in the form of stratification, which has strong stratification characteristics. Therefore, the paper studies the seismic response problem of S-wave incident on the layered elastic ground under thermal effect. Methods: Based on the wave propagation theory in thermoelastic media, the conversion matrix of amplitude coefficients in layered foundations is derived according to the Helmholtz vector decomposition principle and the transfer matrix method. The analytical solution of the seismic response of S-wave incident on layered elastic foundation under thermal effect is obtained. Results: The results show that there is a pretty wide gap between the displacement magnification factors obtained under the two theoretical models considering the thermal effect and not considering the thermal effect; the effect of solid relative heat on displacement magnification factors mainly depends on the thermal stability of soil, and the implications of thermal expansion coefficient on displacement magnification factors is closely related to the size of solid relative heat of soil; in addition, the effects of frequency, medium temperature and the arrangement sequence of the soft and hard soil layers on the displacement magnification factors of the ground surface are significant. Conclusions: This conclusion promotes the application of fluctuation theory in geotechnical engineering seismic resistance, seismic exploration, and other engineering practices and has significant practical value and guiding significance for actual engineering.

Purpose: To investigate the effect of TFF3 in the pathogenesis of Diabetic Kidney Disease (DKD), and explore the dynamic changes of TFF3 expression pattern in renal injury process. Methods: DKD animal model was established by streptozotocin (STZ) (40 mg/kg/d, ip, for 5 days, consecutively) combined with the high fat diet (HFD) for 12 weeks. While animals were sacrificed at different time stages in DKD process (4 weeks, 8 weeks and 12 weeks, respectively). Results: STZ combined with high-fat diet induced weight gain, increased blood glucose and decreased glucose tolerance in DKD mice. Compared to the control group, the DKD group exhibits extracellular matrix (ECM) accumulation and the renal injury was aggravated in a time-dependent manner. The TFF3 expression level was decreased in kidney, and increased in colon tissue. Conclusion: TFF3 is not only expressed in colon, but also expressed in renal medulla and cortex. TFF3 might be play a pivotal role in renal mucosal repair by gut-kidney crosstalk, and protect renal from high glucose microenvironment damage.

The objective of this paper is to understand the dyeability of regenerated keratin textiles from chicken feathers with reactive dyes for industrial applications. Low-value poultry waste has been transformed into high quality keratin filaments and reactive dyes containing α-bromoacrylamide reactive group have been used as precursors to characterize the sorption behavior, colorfastness, and property retention of keratin textiles after dyeing. With efficient recovery of secondary structures and high disulfide crosslinkages, regenerated keratin fibers developed from waste feathers have already demonstrated excellent strength and wet stability at an affordable cost, making them highly promising for industrial applications. To characterize the sorption behavior, reactive dyes are chosen for this study to achieve high wet fastness with minimal fiber damage. The dye adsorption and fixation mechanism of reactive dyes on regenerated keratin fibers agreed well with the Langmuir isotherm model. The maximum adsorption and fixation capacity on keratin fibers were found to be 0.25–0.29 mol/kg and 0.14–0.17 mol/kg. The calculated standard affinity, enthalpy, and entropy from fixation isotherm were found to be in the range of 3.01–5.02 kJ/mol, −34.18 to −35.62 kJ/mol, and −83.76 to −86.07 J/mol·K respectively. These thermodynamic parameters obtained for regenerated keratin fiber fall in between the values for wool and silk, in descending order. Non-linear regression model with multiple terms from Crank’s diffusion equation was found to fit the kinetic data better compared to single term. Regenerated keratin fibers dyed with reactive dyes demonstrated excellent color fastness along with satisfactory strength retention after dyeing, making them suitable for both indoor and outdoor textile applications.

Current in vitromodels for osteosarcoma investigation and drug screening, including two-dimensional (2D) cell culture and tumour spheroids (i.e. cancer stem-like cells), lack extracellular matrix (ECM). Therefore, results from traditional models may not reflect real pathological processes in genuine osteosarcoma histological structures. Here, we report a three-dimensional (3D) bioprinted osteosarcoma model (3DBPO) that contains osteosarcoma cells and shrouding ECM analogue in a 3D frame. Photo-crosslinkable bioinks composed of gelatine methacrylamide and hyaluronic acid methacrylate mimicked tumour ECM. We performed multi-omics analysis, including transcriptomics and DNA methylomics, to determine differences between the 3DBPO model and traditional models. Compared with 2D models and tumour spheroids, our 3DBPO model showed significant changes in cell cycle, metabolism, adherens junctions, and other pathways associated with epigenetic regulation. The 3DBPO model was more sensitive to therapies targeted to the autophagy pathway. We showed that simulating ECM yielded different osteosarcoma cell metabolic characteristics and drug sensitivity in the 3DBPO model compared with classical models. We suggest 3D printed osteosarcoma models can be used in osteosarcoma fundamental and translational research, which may contribute to novel therapeutic strategy discovery.

To evaluate the interbody fusion efficacy and biocompatibility of a graft-free cage made of polyetheretherketone/calcium silicate composite/porous tantalum (PEEK/CS/pTa cage) compared with a PEEK/CS cage with an autogenous bone graft in a goat model.

Selenium (Se) is an essential trace element involved in nearly all human physiological processes but suffers from a narrow margin between benefit and toxicity. The nanoform of selenium has been proven shown to be more bioavailable and less toxic, yet significant challenges remain regarding the efficient and feasible synthesis of biologically active nanoselenium. In addition, although nanoselenium has shown a variety of biological activities, more interesting nanoselenium features are expected. In this work, hydrosoluble nanoselenium termed Nano-Se in the zero oxidation state was synthesized between gray Se and PEG. A zebrafish screen was carried out in zebrafish larvae cocultured with Nano-Se. Excitingly, Nano-Se promoted the action of the FGFR, Wnt, and VEGF signaling pathways, which play crucial roles in tissue regeneration. As expected, Nano-Se not only achieved the regeneration of zebrafish tail fins and mouse skin but also promoted the repair of skin in diabetic mice while maintaining a profitable safe profile. In brief, the Nano-Se reported here provided an efficient and feasible method for bioactive nanoselenium synthesis and not only expanded the application of nanoselenium to regenerative medicine but also likely reinvigorated efforts for discovering more peculiarunique biofunctions of nanoselenium in a great variety of human diseases.

Large bone defects face a high risk of pathogen exposure due to open wounds, which leads to high infection rates and delayed bone union. To promote successful repair of infectious bone defects, fabrication of a scaffold with dual functions of osteo-induction and bacterial inhibition is required. This study describes creation of an engineered progenitor cell line (C3H10T1/2) capable of doxycycline (DOX)-mediated release of bone morphogenetic protein-2 (BMP2). Three-dimensional bioprinting technology enabled creation of scaffolds, comprising polycaprolactone/mesoporous bioactive glass/DOX and bioink, containing these engineered cells. In vivoand in vitroexperiments confirmed that the scaffold could actively secrete BMP2 to significantly promote osteoblast differentiation and induce ectopic bone formation. Additionally, the scaffold exhibited broad-spectrum antibacterial capacity, thereby ensuring the survival of embedded engineered cells when facing high risk of infection. These findings demonstrated the efficacy of this bioprinted scaffold to release BMP2 in a controlled manner and prevent the occurrence of infection; thus, showing its potential for repairing infectious bone defects.

The mechanism underlying EZH2 overexpression in breast cancer and its involvement in tumorigenesis remain poorly understood. In this study, we developed an approach to systematically identify the trans-acting factors regulating the EZH2 expression, and identified more than 20 such factors. We revealed reciprocal regulation of early growth response 1 (EGR1) and EZH2: EGR1 activates the expression of EZH2, and EZH2 represses EGR1 expression. Using CRISPR-mediated genome/epigenome editing, we demonstrated that EHZ2 represses EGR1 expression through a silencer downstream of the EGR1gene. Deletion of the EGR1silencer resulted in reduced cell growth, invasion, tumorigenicity of breast cancer cells, and extensive changes in gene expression, such as upregulation of GADD45, DDIT3, and RND1; and downregulation of genes encoding cholesterol biosynthesis pathway enzymes. We hypothesize that EZH2/PRC2 acts as a “brake” for EGR1 expression by targeting the EGR1silencer, and EZH2 overexpression dampens tumor-suppressive signals mediated by EGR1 to drive breast tumorigenesis.

Diabetic osteoporosis (DOP) is the leading complication continuously threatening the bone health of patients with diabetes. A key pathogenic factor in DOP is loss of osteocyte viability. However, the mechanism of osteocyte death remains unclear. Here, we identified ferroptosis, which is iron-dependent programmed cell death, as a critical mechanism of osteocyte death in murine models of DOP. The diabetic microenvironment significantly enhanced osteocyte ferroptosis in vitro, as shown by the substantial lipid peroxidation, iron overload, and aberrant activation of the ferroptosis pathway. RNA sequencing showed that heme oxygenase-1 (HO-1) expression was notably upregulated in ferroptotic osteocytes. Further findings revealed that HO-1 was essential for osteocyte ferroptosis in DOP and that its promoter activity was controlled by the interaction between the upstream NRF2 and c-JUN transcription factors. Targeting ferroptosis or HO-1 efficiently rescued osteocyte death in DOP by disrupting the vicious cycle between lipid peroxidation and HO-1 activation, eventually ameliorating trabecular deterioration. Our study provides insight into DOP pathogenesis, and our results provide a mechanism-based strategy for clinical DOP treatment.

This review assesses the potential of using plant proteins (wheat gluten and soy proteins) and chicken feather keratin as sizing agents for polyester/cotton (P/C) fabrics. Sizing (slashing) is a critical and essential process required for weaving fabrics. Poly(vinyl alcohol) (PVA) is a traditional size for P/C yarns since PVA readily dissolves in water, provides good sizing performance, and is easily desizeable. However, PVA released from textile effluent treatment affects water organisms. Protein-based sizes required higher percent add-on to provide strength similar to PVA, but had excellent desizing, even at room temperature using low liquor ratios. Similarly, protein-based sizes degraded easily in activated sludge with COD and BOD5values well within the prescribed limits. Plant proteins and feather keratin show promise to replace PVA for sizing P/C fabrics.

Regenerated protein fibers from plant proteins including wheat gluten lack the mechanical properties and water stability desired for usual applications. Crosslinking has been used to improve the properties of regenerated proteins fibers. Although glutaraldehyde is commonly used to crosslink proteins, the effect of various crosslinking conditions on the properties of the materials has not been studied. In this work, a systematic study of glutaraldehyde crosslinking conditions of wheat gluten fibers is presented and shows that even low concentrations of glutaraldehyde 0.05 can improve the strength and water stability of wheat gluten fibers.

Flexural, impact resistance, tensile, and sound absorption properties of composites from cornhusk fiber (CHF) and PP have been investigated. The effect of holding temperature, CHF length, CHF concentration, and enzyme treatment of CHF on mechanical properties and the effect of the latter two on sound absorption have been studied. Compared with jute/PP composites, CHF/PP composites have similar impact resistance, 33% higher flexural strength, 71% lower flexural modulus, 43% higher tensile strength, 54% lower tensile modulus, and slightly higher noise reduction coefficient. Enzyme treatment of CHF results in increased mechanical and sound absorption properties.

Molecular modeling is used to explain how the resistance of poly[(L-lactide)‐co‐(D‐lactide)] to hydrolysis is affected by the percentages of L‐ and D‐lactide and their arrangements in blocks or random arrangements in the polymer. Previous studies on improving the hydrolysis resistance of PLA have involved forming either poly(L‐lactide)/poly(D‐lactide) (PLLA/PDLA) polyblends or copolymers of L‐ and D‐lactide. In this study, molecular modeling was used to study the hydrolysis resistance of PLA containing various arrangements of L‐ and D‐lactide in the polymers. PLA copolymers are found to have less resistance to hydrolysis than a PLLA/PDLA polyblend having the same percentages of L‐ and D‐lactide because a polyblend can form more stereocomplexes, which is the most stable structure PLA can form.

The existence of lignin in lignocellulosic fibers increases the loss in breaking tenacity and elongation of fibers when they are exposed to heat and light. Delignification by sulfonation helps to remove some of the lignin from the fibers without affecting the breaking tenacity. The delignified fibers have higher resistance to heat and light exposure compared to the raw fibers. The effect of lignin on the heat and light resistance of kenaf and cornhusk fibers with three different lignin contents was studied in comparison to cotton at various periods of heat and light exposure. The changes in the breaking tenacity, breaking elongation and yellowness of the samples were studied.

Molecular modeling is used to explain how grafting various molecules that contain large aromatic structures and different reactive groups onto cellulose dramatically increases the hydrolysis of the glycosidic linkages of cellulose. Hydrolysis is found to increase with the increasing size of the molecule grafted to cellulose, and experiments support this finding. A larger substituent on cellulose increases hydrolysis by causing the hydrolyzed cellulose structure to be more stable compared to hydrolyzed cellulose grafted to a smaller substituent. A larger substituent forms stronger interactions with cellulose and has a greater ability to reduce the mobility of the cleaved cellulose chain to which it is bonded, which allows the cleaved cellulose to form stronger cellulose-cellulose interactions after hydrolysis. A substituent on the C6 position of cellulose increases hydrolysis to a greater extent than does the same substituent on the C3 or C2 position.

Polypropylene–clay nanocomposites were prepared by a solution technique and a subsequent melt‐mixing process. A titanate coupling agent was used to improve the compatibility of the nanoclay particles with the polypropylene. The dispersion of the nanoclay particles in polypropylene was studied with X‐ray diffraction (XRD) and transmission electron microscopy (TEM). An increased d‐spacing value of the clay particles in the nanocomposites was observed, and it was compared with the values of as‐mined (pristine) and as‐received (organophilic) clay particles. The number of intercalated layers in a single clay crystallite was determined to be 4, and the number was confirmed with XRD data and TEM images. On the basis of the Daumas–Herold model (which is widely used for graphite intercalation compounds), the stage 2 and stage 3 structures of montmorillonite particles in polypropylene were recommended. A study on the stage structure suggested a way of determining the presence of polymer molecules in the clay galleries. The results confirmed the existence of single‐layered platelets with improved dispersion in polypropylene. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 218–226, 2005

The solubility parameters of polylactide (PLA), poly(ethylene terephthalate) (PET), and various disperse dyes calculated according to the group contribution method were used to explain the low sorption of some disperse dyes on PLA but the high sorption of the same dyes on PET. It was found that the dyes with high sorption on PLA tended to have solubility parameters near that of PLA, which has a lower solubility parameter than that of PET. It was also found that the solubility parameter, which was calculated based on cohesive energy and molar volume at 25°C, was more appropriate for explaining dyeings at lower temperature, 100 and 110°C, than those at higher temperature, 130°C. Based on the finding that dyes with solubility parameters near that of PLA tend to have high sorption on PLA, general structures for disperse dye that may have high sorption on PLA were proposed. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 416–422, 2005

For the first time, natural cellulose fibers having properties between cotton and linen and suitable for various industrial applications have been extracted from cornhusks. High quality cellulosic fibers from cornhusks mean food, clothing and other major industrial products from the same source without the need for any additional natural resources. Using cornhusks for fibrous applications would save the land and other natural resources required to grow fiber crops and will conserve the non-renewable petroleum sources required to produce synthetic fibers. More than 9 million tons of natural cellulose fibers with a potential sale value of $19 billion with a value addition of at least $12 billion can be produced from the cornhusks available every year. Utilizing cornhusks as a source for natural cellulose fibers will significantly benefit the agriculture, fiber, food and energy needs of the future and will also benefit the environment.

Ten popular disperse dyes with different energy levels and chemical constitutions were used to compare their exhaustion, color yield, and colorfastness on polylactide (PLA) and poly(ethylene terephthalate) (PET). Only two out of the 10 dyes had exhaustions higher than 80% on PLA at 2% owf. Five out of the 10 dyes had exhaustions less than 50%. All 10 dyes had more than 90% exhaustion on PET, whereas six of them had exhaustions of 98% or higher. There was no obvious pattern as for which energy level or which structure class provided dye exhaustion better than that of others. Although PLA had lower disperse dye exhaustion than that of PET, it had higher color yield. Based on the 10 dyes examined, the color yield of PLA was about 30% higher than that of PET. This means that even with low dye uptake, PLA could have a similar apparent shade depth as that of PET if the same dyeing conditions are applied. Our study supported that the lower reflectance, or reflectivity, of PLA contributes to the higher color yield of PLA than that of PET. A quantitative relation between the shade depth of PLA and PET based on their dye sorption was developed. Disperse dyes examined had lower washing and crocking fastness on PLA than on PET. The differences in class were about 0.5 to 1.0. If the comparison was based on the same dye uptake, the differences might be larger. The differences in light fastness between the two fibers were smaller than that in washing and crocking fastnesses. The light fastness of disperse dyes on PLA is expected to be even better if the comparison is based on the same dye uptake on both fibers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3285–3290, 2003

Sorption characteristics, such as sorption kinetics and isotherms, relation between dye sorption and shade development of poly(trimethylene terephthalate) (PTT) and their comparison with poly(ethylene terephthalate) (PET), were reported. Results from two different dyeing rate studies, dyeing rate under constant temperature and under changing temperature, were examined to obtain the common rate constants, and to obtain information for the design of dyeing temperature profile and holding time. Rate constants of PTT were compared with that of PET. Sorption isotherms of disperse dyes on PTT were also studied. Both Nernst and Langmuir models were examined. The dye uptake ability of PTT was compared with PET. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 223–229, 2002

Rolled, continuous stationary phases were constructed by tightly rolling and inserting a whole textile fabric into a chromatography column. This work reports the column performance, in terms of plate height, void fraction, and resolution, of 10 cellulose‐based fabrics. The relation between fabric structural properties of yarn diameter, fabric count, fabric compressibility, and column performance are quantitated. General requirements, including reproducibility of packing, for choosing fabrics to make a good SEC column are identified. This research showed that the packed columns have an optimal mass of fabric that minimizes plate height and maximizes resolution, in a manner that is consistent with chromatography theory. Mass of material packed is then an important column parameter to consider when optimizing columns for the rapid desalting of proteins. Proteins were completely separated from salt and glucose in less than 8 min at a pressure drop less than 500 psi on the rolled, continuous stationary‐phase columns. These results, together with stability and reproducibility, suggest potential industrial applications for cellulose‐based rolled, continuous stationary‐phase columns where speed is a key parameter in the production process.

One concern associated with wet-on-wet processing is the changing chemical concentration in the pad bath. After processing for several hundred yards or so, chemical add-on considerably decreases, resulting in poor performance properties of finished goods or decreased shade depth. To obtain a constant bath concentration and add-on, an appropriate initial concentration and a reconstitution stream with higher concentration than the initial concentration should be used. The validity of a mathematical model relating parameters in wet-on-wet padding is proven by experimental data from both laboratory and production scales. Using that model, changes in pad bath concentration can be quantitatively described. For given processing conditions and add-on requirements, an initial pad concentration and a different reconstitution concentration can be obtained from the model to assure a constant add-on from the beginning to the end of the wet-on-wet process.

Concentration of water soluble direct, acid, basic, and reactive dyes occurs when dilute solutions are frozen at a temperature below the melting point and above the eutectic point of the solution. When freezing is done in still solution, a concentration of up to 500% is achieved in one step, with the dye solution collecting in an oblately spheroidal liquid pocket surrounded by clear ice containing voids, formed from air pockets, radiating outward. Three repetitive freezing cycles concentrate the dye 13,000%. The higher the water solubility of the dye, the lower the ability to concentrate during freezing. The freezing rate of four acid and direct dyes had no close relationship with the size of the dyes studied. Over a larger molecular weight range, an effect was observed for other kinds of molecules. Freeze concentration of salt solution (MW = 58.5 ) gives almost a 700% concentration, detergent solution (sodium dodecyl sulfate, MW = 288.4) gives 400%, and bovine serum albumin, a large water soluble macro molecule (MW = 66,200), gives 160%. A theory is presented suggesting that the concentration effect and the formation of the central sphere are consistent with min imizing of the free energy of the overall system. This simple technique may find application in the concentration of heat sensitive, labile dyes for analytical purposes, as well as in the recovery of dyes and other chemicals on a bench scale.

Frontal analysis gives retention volumes of basic dyes on acrylic fabric, rolled and inserted into a liquid chromatography column. The retention volumes indicate differences in adsorption and therefore in compatibilities of standard dye mixtures. A simple and useful relation, Cv= Cvo+ mR- Cv,0, results where mis a parameter fitted to the data, Cv0 is the compatibility difference between Cvoand Cvwhen R= 0 (i.e., elution times are identical), and Cvois the compatibility of one of the two dyes in the mixture. Hence, a new approach is proposed that not only allows determination of Cvusing frontal analysis with an LC apparatus, but also defines compatibility in an objective manner as a continuous function.

Direct dye adsorption isotherms have been obtained using a rolled cotton fabric stationary phase in a liquid chromatography column. Both frontal analysis and minor disturbance methods were tested. The minor disturbance method was not useful due to the slow rate of dye equilibration relative to the velocity of the pulse of dye passed through the fabric column. In comparison, the frontal analysis technique gave results similar to those obtained with standard equilibrium adsorption measurements in a beaker. This method permits determination of whole fabric dye sorption using liquid chromatography instrumentation in a manner that yields facile and quantitative measures of dye compatibility, as described in Part II of this paper.

Traditional anionic dyeing of cotton requires large amounts of salt to assist dye sorption. This paper reports a method of using trimethylolmelamine (TMM), a com mon durable press finish, to treat cotton for dyeing. TMM pretreated cotton has re markably improved affinity for anionic dyes and no longer needs the assistance of salt in the dyebath. Furthermore, effluents from such processes contain much less dye than effluents from ordinary salt-assisted dyeings. This technology not only increases the efficiency of dyeing without salt, it also considerably decreases the burden of effluent treatment. By this method, cotton can also be dyed with acid dyes.

The modified Donnan model, which considers the dye distribution coefficient as a function of salt concentration and property in the dyebath, is used to describe the dyeing behavior of wool with acid dyes and different kinds of salts. This modification is based on the understanding that salt anions are either kosmotropes (water-structure maker) or chaotropes (water-structure breaker). They affect the free energy of the dyebath through their influence on water structures. As is well known, adding salt to the dyebath decreases dye sorption due to its reduction of ionic attraction between negatively charged acid dyes and positively charged wool fibers. However, adding some salts such as sulfate and dihydrogen phosphate can increase dye sorption if the salt concentration is high. This phenomenon cannot be explained by the classic theory of salt functions in dyeing. The modified Donnan model is used to explain quantitatively both the de crease and increase of acid dye sorption on wool with increasing salt concentration.

Clinic treatment of diabetic foot ulcers (DFUs) is considerably challenging. Impaired wound healing may be caused by poor vascularization and dysfunction of the extracellular matrix, which leads to poor re-epithelialization and increased risk of infection. In this study, we evaluated the treatment potential of a functional dressing comprising quaternized chitosan (hydroxypropyltrimethyl ammonium chloride chitosan) and magnesium (Mg) on DFUs.

In this paper, silicates/poly (l-lactic acid)-co-bisphenol A epoxy resin assemblies with high modulus were developed by in situpolymerization of l-lactic acid and surface-modified lamellar vermiculites for potential applications in tissue engineering. These assemblies represented advances in the mechanical properties that can be hardly obtained in other assemblies formed via physical interactions. The covalent grafting of the PLLA based polymers onto the vermiculites surface was confirmed by X-ray photon spectroscopy. The elastic moduli of the assemblies measured by an atomic force microscope were around 7 GPa, and higher than the elastic moduli of the pure polymer (3.2 GPa) and unmodified vermiculites (1.5 GPa), respectively. Images demonstrated that cells proliferated and reached confluence on both the assemblies and pure polymer materials, which indicated that the assemblies exhibited the similar cytocompatibility with pure polymer. With the addition of 5 wt.% assemblies, the polymer and assemblies blended-composites exhibited a 118% improvement in compressive strength and 117% improvement in modulus compared with pure polymer. The present work demonstrated a strategy for the assembly of biomacromolecules and inorganic layers and fabrication of biomaterials high in modulus for tissue engineering applications.