Current developments and opportunities of pluripotent stem cells-based therapies for salivary gland hypofunction

Salivary gland hypofunction (SGH) caused by systemic disease, drugs, aging, and radiotherapy for head and neck cancer can cause dry mouth, which increases the risk of disorders such as periodontitis, taste disorders, pain and burning sensations in the mouth, dental caries, and dramatically reduces the quality of life of patients. To date, the treatment of SGH is still aimed at relieving patients’ clinical symptoms and improving their quality of life, and is not able to repair and regenerate the damaged salivary glands. Pluripotent stem cells (PSCs), including embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), and extended pluripotent stem cells (EPSCs), are an emerging source of cellular therapies that are capable of unlimited proliferation and differentiation into cells of all three germ layers. In recent years, the immunomodulatory and tissue regenerative effects of PSCs, their derived cells, and paracrine products of these cells have received increasing attention and have demonstrated promising therapeutic effects in some preclinical studies targeting SGH. This review outlined the etiologies and available treatments for SGH. The existing efficacy and potential role of PSCs, their derived cells and paracrine products of these cells for SGH are summarized, with a focus on PSC-derived salivary gland stem/progenitor cells (SGS/PCs) and PSC-derived mesenchymal stem cells (MSCs). In this Review, we provide a conceptual outline of our current understanding of PSCs-based therapy and its importance in SGH treatment, which may inform and serve the design of future studies

Study on Anchor Cable instead of Single Hydraulic Prop Support in Advance Support of Deep Roadway

In order to solve the problems of complicated advanced support process, high labor intensity, affecting the rapid advance of working face and the destruction of roof bolt (cable) by advance single hydraulic prop in ultra kilometer deep mine roadway, the deformation characteristics of roadway surrounding rock is analyzed. Taking the 27304 working face of Wanglou coal mine as the engineering background, numerical simulation, field monitoring, and theoretical calculation were used to analyze the deformation characteristics of roadway surrounding rock within the advanced influence range of 27304 working face. This paper puts forward the active advance support technology scheme, in which grouting anchor cable replaces the existing single hydraulic prop in the advance influence range of the working face in the ultra-kilometer deep mine, and observes and analyzes the deformation and failure characteristics of the surrounding rock of the working face advance roadway. The numerical simulation results show that in the advanced influence range of deep roadway, grouting anchor cable was used to replace the previous single hydraulic prop, and the vertical stress at both ends of the working face decreased by 15 MPa, with a decrease rate of 33.3%; the displacement of roadway roof, floor, and two sides decreased by 10 mm, 55 mm, and 20 mm, with a decrease rate of 40%, 68.75%, and 47.6%, respectively. The field monitoring results show that the roof separation is obviously improved after using grouting anchor cable as the active advance support scheme. It solves the problem of safe and efficient production faced by the ultra-kilometer deep shaft in Wanglou coal mine and provides theoretical and technical support for unmanned double roadway advance support under the condition of safe and efficient mining

Biosorption of Heavy Metal Ions from Aqueous Solution on Chinese Fir Bark Modified by Sodium Hypochlorite

The oxidation conditions and adsorption ability of Cu (II), Cd (II), and Pb (II) from an aqueous solution of sodium hypochlorite-oxidized fir bark powder were investigated. The optimum amount of NaClO was 9.6%, the pH was 9, and the oxidation time was 120 min. Batch adsorption experiments were carried out with various times, pH values, and initial metal ion concentrations. The adsorption isotherms and kinetics of adsorption were also studied. The maximum adsorption capacity of oxidized fir bark was 0.983, 1.223, and 0.966 mmol/g for Cu (II), Cd (II), and Pb (II), respectively, within 30 min at pH 5, higher adsorption capacity than that of unoxidized fir bark. The isothermal adsorption of heavy metal ions in aqueous solution was a good fit to the Langmuir equation, with a coefficient of determination, R2, above 0.99. The adsorption of fir bark on metal ions can be appropriately approximated by a pseudo-second order adsorption kinetics model. Results indicate that the fir bark powder modified with sodium hypochlorite can adsorb large amounts of metal ions and could be a good adsorbent for the removal of Cu(II), Cd(II), and Pb(II) from aqueous solution

Fouling Characteristics of Dissolved Organic Matter in Papermaking Process Water on Polyethersulfone Ultrafiltration Membranes

In the papermaking industry, closure of process water (whitewater) circuits has been used to reduce fresh water consumption. Membrane separation technology has potential for use in treating process water for recirculation. The purpose of this study was to reveal the fouling characteristics of a polyethersulfone (PES) ultrafiltration membrane caused by dissolved organic matter (DOM) in process water. Ultrafiltration membranes (UF) and DAX ion exchange resins were applied to characterize the molecular weight (MW) and hydrophilicity distribution of DOM. The interactions between various fractions of DOM and a PES ultrafiltration membrane were investigated. The membrane fouling characteristics were elucidated by examining the filtration resistances and linearized Herman’s blocking models. The results demonstrated that the membrane was fouled significantly by much of the MW distribution. The membrane was fouled more significantly by the low MW fraction rather than the high MW fraction. The filtration resistances and the fitted equation of Hermia’s laws indicated that hydrophilic organics were the main foulants. The hydrophilic organics partially block the membrane pores and form intermediate blocking, reducing the effective filtration area, while the hydrophobic organics form a gel layer or cake on the surface of the membrane

Filtering Whitewater with an Ultrafiltration Membrane: Effects of the Interaction between Dissolved Organics and Metal Ions on Membrane Fouling

The mechanisms regarding the influence of dissolved organics in papermaking whitewater together with metal ions on the fouling of an ultrafiltration (UF) membrane were studied in this paper. A series of experiments were carried out to characterize the organic matters’ size and membrane flux. The associated fouling mechanism was investigated using the modified Hermia empirical model, resistance distribution, and specific resistance of the cake layer. The results indicated that the addition of metal ions aggravated membrane fouling. Increasing concentrations of metal ions resulted in the higher specific resistance of the cake layer and greater membrane fouling due to their chelation with dissolved organics. Increased pH values influenced the interaction between the metal ions and dissolved organics, resulting in a relatively slow membrane flux decline. Increasing concentrations of Na+ resulted in greater membrane fouling. Cake layer formation played a major role in treating the water samples with high-concentration metal ions, whereas intermediate blocking formation may be the dominant fouling mechanism when treating the solution without metal ions

Dynamics and Complexity Analysis of Fractional-Order Chaotic Systems with Line Equilibrium Based on Adomian Decomposition

In this paper, the Adomian decomposition method (ADM) is applied to solve the fractional-order system with line equilibrium. The dynamics of the system is analyzed by means of the Lyapunov exponent spectrum, bifurcations, chaotic attractor, and largest Lyapunov exponent diagram. At the same time, through the Lyapunov exponent spectrum and bifurcation graph of the system under the change of the initial value, the influence of fractional order q on the system state can be observed. That is, integer-order systems do not have the phenomenon of attractors coexistence, while fractional-order systems have it

A non-contact interactive stereo display system for exploring human anatomy

Stereoscopic display based on Virtual Reality (VR) can facilitate doctors to observe the 3 D virtual anatomical models with the depth cues, assist them in intuitively investigating the spatial relationship between different anatomical structures without mental imagination. However, there is few input device can be used in controlling the virtual anatomical models in the sterile operating room. This paper presents a cost-effective VR application system for demonstration of 3 D virtual anatomical models with non-contact interaction and stereo display. The system is integrated with hand gesture interaction and voice interaction to achieve non-contact interaction. Hand gesture interaction is implemented based on a Leap Motion controller mounted on the Oculus Rift DK2. Voice is converted into operation using Bing Speech for English language and Aitalk for Chinese language, respectively. A local relationship database is designed to record the anatomical terminologies to speech recognition engine to query these uncommon words. The hierarchical nature of these terminologies is also recorded in a tree structure. In the experiments, ten participants were asked to perform the evaluation on the proposed system. The results show that our system is more efficient than traditional interactive manner and verify the feasibility and practicability in the sterile operating room

Application of Ultrafiltration in a Paper Mill: Process Water Reuse and Membrane Fouling Analysis

High water consumption is a major environmental problem that the pulp and paper industry is facing. Ultrafiltration (UF) can be used to remove the dissolved and colloidal substances (DCS) concentrated during the recycling of white water (the process water) to facilitate the reuse of white water and reduce fresh water consumption. However, membrane fouling limits the application of UF in this industry. In this study, super-clear filtrate obtained from a fine paper mill was purified with a polyethersulfone (PES) ultrafiltration membrane to evaluate the reuse performance of the ultrafiltrate. The membrane foulants were characterized by scanning electron microscopy, energy-dispersive spectrophotometry, attenuated total reflection-fourier transform infrared spectroscopy, and gas chromatography-mass spectrometry. The results indicate that the retention rate of stock and the strength properties of paper increased when the ultrafiltrate was reused in the papermaking process compared to when super-clear filtrate was used. The reversible membrane foulants during ultrafiltration accounted for 85.52% of the total foulants and primarily originated from retention aids, drainage aids, and wet strength resins, while the irreversible adsorptive foulants accounted for 14.48% and mostly came from sizing agents, coating chemicals, and others. Moreover, the presence of dissolved multivalent metal ions, especially Ca2+, accelerated membrane fouling