Industrial utilization of arsenic-containing gold dressing tailings as pellet prepared by straight grate process

The utilization of arsenic-containing gold dressing tailings is an urgent issue faced by gold production companies worldwide.The thermodynamic analysis results indicate that ferrous arsenate(FeAsO_(4)),pyrite(FeS_(2))and sodium cyanide(NaCN)in the arsenic-containing gold metallurgical tailings can be effectively removed using straight grate process,and the removal of pyrite and sodium cyanide is basically completed during the preheating stage,while the removal of ferrous arsenate requires the roasting stage.The pellets undergo a transformation from magnetite to hematite during the preheating process,and are solidified through micro-crystalline bonding and high-temperature recrystallization of hematite(Fe_(2)O_(3))during the roasting process.Ultimately,pellets with removal rates of 80.77% for arsenic,88.78% for sulfur,and 99.88% for cyanide are obtained,as well as the iron content is 61.1% and the compressive strength is 3071 N,meeting the requirements for blast furnace burden.This study provides an industrially feasible method for treating arsenic-containing gold smelting tailings,benefiting gold production enterprises.

Spatially engineering tri-layer nanofiber dressings featuring asymmetric wettability for wound healing

Inspired by the skin structure,an asymmetric wettability tri-layer nanofiber membrane(TNM)consisting of hydrophilic inner layer loaded with lidocaine hydrochloride(LID),hydrophobic middle layer with ciprofloxacin(CIP)and hydrophobic outer layer has been created.The hydrophobic outer layer endows the TNM with waterproof function and anti-adhesion from contaminants.The hydrophobic middle layer with CIP preserves long-term inhibition of bacteria growth and the hydrophilic inner layer with LID possesses optimal waterabsorbing capacity and air permeability.The TNM dramatically elevates the water contact angles from 10°(inner layer)to 120(outer layer),indicating an asymmetric wettability,which could directionally transport wound exudate within the materials and meanwhile maintain a comfortable and moist environment to promote wound healing.Furthermore,the sequential release of LID and CIP could relieve pain rapidly and achieve antibacterial effect in the long run,respectively.In addition,the TNM shows superior biocompatibility towards L929 cells.The in vivo results show the TNM could prevent infection,accelerate epithelial regeneration and significantly accelerate wound healing.This study indicates the developed TNM with asymmetrical wettability and synergetic drug release shows great potential as a wound dressing in clinical application.

Improving pressure ulcer care in intensive care units:Evaluating the impact of bundled care and silver nanoparticle dressings

BACKGROUND Pressure ulcer(PU)are prevalent among critically ill trauma patients,posing substantial risks.Bundled care strategies and silver nanoparticle dressings offer potential solutions,yet their combined effectiveness and impact on patient satisfaction remain insufficiently investigated.AIM To assess the impact of bundled care along with silver nanoparticle dressing on PUs management and family satisfaction in critically ill trauma patients.METHODS A total of 98 critically ill trauma patients with PUs in intensive care unit(ICU)were included in this study.Patients were randomly assigned to either the control group(conventional care with silver nanoparticle dressing,n=49)or the intervention group(bundled care with silver nanoparticle dressing,n=49).The PU Scale for Healing(PUSH)tool was used to monitor changes in status of pressure injuries over time.Assessments were conducted at various time points:Baseline(day 0)and subsequent assessments on day 3,day 6,day 9,and day 12.Family satisfaction was assessed using the Family Satisfaction ICU 24 ques-tionnaire.RESULTS No significant differences in baseline characteristics were observed between the two groups.In the intervention group,there were significant reductions in total PUSH scores over the assessment period.Specifically,surface area,exudate,and tissue type parameters all showed significant improvements compared to the control group.Family satisfaction with care and decision-making was notably higher in the intervention group.Overall family satisfaction was significantly better in the intervention group.CONCLUSION Bundled care in combination with silver nanoparticle dressings effectively alleviated PUs and enhances family satisfaction in critically ill trauma patients.This approach holds promise for improving PUs management in the ICU,benefiting both patients and their families.

Antibacterial and angiogenic dual-functional fibrous membrane dressing for infected wound healing

Background:Skin,being a vital organ that regulates physiological responses in the human body,is prone to injury from external environmental factors.Healing full-thickness skin defects becomes especially challenging when infections and vascular injuries are involved.Traditional wound dressings with single functions,such as antibacterial or angiogenic properties,fall short in achieving rapid wound healing.To address this,there is a need to develop wound dressing materials that possess both effective antibacterial and angiogenic properties.Methods:In this study,we utilized electrospinning technology to fabricate hyaluronic acid-cellulose acetate fibrous membrane dressings,incorporating poly(ionic liquid)as an antibacterial polymer and deferoxamine as an angiogenic agent.Results:The resulting fibrous membrane dressing contained poly(ionic liquid)and deferoxamin showcased a microporous structure,drug-releasing capabilities,and excellent air permeability.It not only demonstrated highly effective antibacterial properties but also exhibited remarkable angiogenesis,thereby promoting the healing of full-thickness skin defect wounds in both in vitro and in vivo assays.Conclusion:These findings highlight the immense potential of this wound dressing material for future clinical applications.

Janus hydrogel/electrospun-membrane dressing enhancing wound healing in rats

Background:Excessive exudate secreted from chronic wounds often leads to overhydration and infection.Although a variety of dressings are currently available in clinical applications,they frequently fail to provide multifunction to promote chronic wound healing.The dressings with a Janus structure,featuring distinct properties on each side,are potential to improve wound healing.Methods:Composite dressings with a Janus structure were fabricated,comprising freeze-dried polycaprolactone(PCL)electrospun membrane and alginate-based hydrogel.The PCL fibrous membrane provided air permeability,while the hydrogel loaded with Deferoxamine,composed of alginate and poly(N-isopropylacrylamide)(PNIPAM),exhibited hygroscopic properties.The inclusion of PNIPAM imparted thermo-responsivity.Results:The hydrogel(thickness of 2.778±0.082 mm)exhibited a robust adhesion to the fiber membrane(thickness of 0.261±0.041 mm).For ANDC(Alginate-PNIPAM hydrogel with Deferoxamine/PCL membrane)samples,the water vapor transmission rate(WVTR)was measured to be 3364.80±23.23 g∙m−2∙day−1 and the swelling ratio at 2 h was determined to be 1179±125%.The thermo-responsivity of ANDC samples manifested in an increased swelling rate,escalating from 797±189%at 37°C to 1132±147%at 4°C.The elastic modulus was assessed for lyophilized and rehydrated ANDC sample.When theωof the rheometer rotor was decreased from 10 rad/s to 0.1 rad/s,the lyophilized dressing exhibited a decrease from 2.65±0.01 MPa to 1.80±0.90 MPa,while the rehydrated dressing demonstrated an increase from 133.65±55.68 Pa to 264.23±141.71 Pa.The pro-healing properties of the dressings were evaluated using full-thickness skin defect model on SD rats,and a circular wound of diameter 10 mm healed completely by day 12.Conclusion:The dressings not only protected the wound and absorbed excess exudate,but also demonstrated nondestructive peelability upon cooling,providing a novel approach for accelerating wound healing and management.

Effects of honey dressing for the treatment of DFUs: A systematic review

Background:Honey dressing has been applied to clinical practice for many types of disease for centuries.Many researchers have studied the effects of honey dressing for the treatment of DFUs(diabetic foot ulcers),and no systematic review has considered effects of honey dressing on DFUs.A systematic review performed to objectively evaluate the effectiveness of honey dressing in the treatment of DFUs.Methods:We include all original studies found for the key words honey and diabetic foot ulcers.Mean effect sizes and confidence intervals are pooled from study effect sizes according to standard methods,and these are considered for various common types of honey dressing interventions separately.Results:A total of 4 RCTs involving 258 participants were included,and 3 trails involving 228 participants met the quantitative analysis and 1 study involving 30 participants met qualitative analysis.Results of meta and descriptive analyses showed that total treatment time,Mean purge time of ulcers,ratio of purging germ,healed area of ulcers in honey dressing group are better than that of control group,respectively,and with statistically significant differences.Conclusions:Honey dressing was superior of traditional dressing for treatment of DFUs.Due to limitations in the quantity of published studies,this conclusion has yet to be carried out in large,multicenter study to validate.

Design of Novel Wound Dressing Composed of Collagen and Hyaluronic Acid Containing Epidermal Growth Factor

This research aims to develop a wound dressing composed of collagen (Col) and hyaluronic acid (HA) containing epidermal growth factor (EGF). First important issue is to contain EGF in the wound dressing in a stable state. The sheet-shaped sponge was manufactured by freeze-vacuum drying an aqueous solution of Col. Both sides of sponge were treated with ultraviolet (UV) irradiation to introduce intermolecular cross links between collagen molecules. This sponge was named Sponge-Col. Another sheet-shaped sponge was manufactured by freeze-vacuum drying an aqueous solution of HA containing EGF. This sponge was named Sponge-HA/EGF. The wound dressing was manufactured by laminating Sponge-Col on the top, Sponge-HA/EGF in the middle, and Sponge-Col on the bottom to create a sandwich structure. This method can prevent the reducing of EGF activity due to UV irradiation for intermolecular cross-linking. Second important issue is to enable gradual release of EGF from the wound dressing. The elution behavior of this wound dressing was investigated by measuring the weight change after immersion in water for a predetermined time. This wound dressing showed initially fast elution and subsequent very slow elution properties. The upper layer and lower layer Sponge-Col enabled gradual release of the middle layer Sponge-HA/EGF. This result suggests that EGF contained in the wound dressing is gradually released together with HA from the wound dressing. Third important issue is to provide moist wound-healing environment. The upper layer and lower layer Sponge-Col can provide the wound dressing with high water absorption and long-term water retention properties.

Curative Effect of 30% Supramolecular Salicylic Acid Combined with Yufa Spray Dressing on Moderate to Severe Scalp Seborrheic Dermatitis

Objective:To observe the clinical efficacy of 30%supramolecular salicylic acid combined with Yufa spray dressing in the treatment of moderate to severe seborrheic dermatitis(seborrheic dermatitis of the scalp,SDS).Methods:From January 2020 to December 2021,150 patients with SDS,who were treated in the Dermatology Clinic of the First Affiliated Hospital of Xi’an Medical University,were randomly divided into two groups,a treatment group and a control group,with 75 cases in each group.The treatment group was given 30%supramolecular salicylic acid combined with Yufa spray dressing on the basis of external medicine given to the control group,while the control group was given oral medicine combined with external medicine.Results:The difference in scores of erythema,scales,pruritus,and folliculitis of the treatment group before and after treatment was significant(P<0.01),indicating that supramolecular salicylic acid combined with Yufa spray dressing can relieve the symptoms of SDS.The difference in scores of erythema of the control group before and after treatment was significant as well(P<0.05),indicating that traditional antibiotics are also effective in treating SDS;however,there was no significant difference(P>0.05)in the scores of other signs and symptoms,such as scales,pruritus,and folliculitis,before and after treatment,indicating that traditional antibiotics have no obvious curative effect on SDS.After 12 weeks of treatment,the improvement in erythema,scaling,and folliculitis was significantly greater in the treatment group compared with the control group(P<0.05).Curative effect comparison showed that the total effective rate of the treatment group was 80.00%,compared with 25.67%of the control group,and the difference was statistically significant(P<0.05).Conclusion:30%supramolecular salicylic acid combined with Yufa spray dressing can significantly improve the therapeutic effect in moderate to severe SDS;the recurrence rate is lower,the course of treatment is shorted,and patients generally feel better;thus,it is a new option for the treatment of dermatitis.

Mesenchymal stem cells in wound healing:A bibliometric analysis as a powerful research tool

Bibliographic analysis is still very rarely used in experimental basic study papers.The comprehensive bibliometric analysis of scientific literature on research progress and challenges in stem cell therapy for diabetic chronic wounds,which was conducted in the work of Shi et al can be a case study and a source of valuable information for writing reviews and experimental papers in this field.Basic experimental studies on a role of mesenchymal stem cells(MSCs)in wound healing that are published in 2023-2024,such as Zhang et al in 2023,Hu et al in 2023,Wang et al in 2023 are certainly also subjects for applying this powerful tool to analyze current research,challenges and perspectives in this field.This is due to the fact that these studies have addressed a great variety of aspects of the application of MSCs for the treatment of chronic wounds,such as using both the cells themselves and their various products:Sponges,hydrogels,exosomes,and genetic constructions.Such a wide variety of directions in the field of study and biomedical application of MSCs requires a deep understanding of the current state of research in this area,which can be provided by bibliometric analysis.Thus,the use of such elements of bibliographic analysis as publication count by year and analysis of top-10 keywords calculated independently or cited from bibliometric analysis studies can be safely recommended for every basic study manuscripts,primarily for the“Introduction”section,and review.

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Clothes can be formal or casual.Most people dress up if they're going to an important event.They may wear a fancy dress or suit to a wedding ora dinner party.People often wear casual clothes to school or work.Men and women may wear pants andashirt.

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“Mom,I want to eat Moo Shu Pork,”Zhu Rui exclaimed eagerly.“Okay,let me prepare the meat.I'll let you know when I'm done,”his mother replied with a warm smile.Sitting comfortably in her chair dressed in rosy pajamas featuring a large picture of Mickey Mouse,she looked at her son through the computer screen with tender eyes.

New Furniture

Do you like new furniture?You can get some for your house or apartment.A new bed and a new dresser for your bedroom are nice.The bed can be big or small.You may want a new sofa and big chairs for your living room.A new bookcase is nice,too.But furniture can be expensive.Can you afford it?

Magnetizing Roasting Mechanism and Effective Ore Dressing Process for Oolitic Hematite Ore

Magnetizing roasting of oolitic hematite ore from western Hubei Province was investigated.The mechanism for reduction roasting of oolitic hematite ore was discussed and analyzed.It is found that flash magnetizing roasting-magnetic separation process is a promising approach for the processing of oolitic hematite ore from western Hubei Province.

Electrospun nanofibers as a wound dressing for treating diabetic foot ulcer

Diabetes is one of the most prevalent diseases in the world with high-mortality and complex complications including diabetic foot ulcer(DFU). It has been reported that the difficulties in repairing the wound related to DFU has much relationship with the wound infection,change of inflammatory responses, lack of extracellular matrix(ECM), and the failure of angiogenesis. Following the development of medical materials and pharmaceutical technology, nanofibers has been developed by electrospinning with huge porosity, excellent humidity absorption, a better oxygen exchange rate, and some antibacterial activities. That is to say, as a potential material, nanofibers must be a wonderful candidate for the DFU treatment with so many benefits. Careful selection of polymers from natural resource and synthetic resource can widen the nanofibrous application. Popular methods applied for the nanofibrous fabrication consist of uniaxial electrospinning and coaxial electrospinning. Furthermore, nanofibers loading chemical, biochemical active pharmaceutical ingredient(API)or even stem cells can be wonderful dosage forms for the treatment of DFU. This review summarizes the present techniques applied in the fabrication of nanofibrous dressing(ND)that utilizes a variety of materials and active agents to offer a better health care for the patients suffering from DFU.

Antibacterial biomaterials for skin wound dressing

Bacterial infection and the ever-increasing bacterial resistance have imposed severe threat to human health.And bacterial contamination could significantly menace the wound healing process.Considering the sophisticated wound healing process,novel strategies for skin tissue engineering are focused on the integration of bioactive ingredients,antibacterial agents included,into biomaterials with different morphologies to improve cell behaviors and promote wound healing.However,a comprehensive review on antibacterial wound dressing to enhance wound healing has not been reported.In this review,various antibacterial biomaterials as wound dressings will be discussed.Different kinds of antibacterial agents,including antibiotics,nanoparticles(metal and metallic oxides,lightinduced antibacterial agents),cationic organic agents,and others,and their recent advances are summarized.Biomaterial selection and fabrication of biomaterials with different structures and forms,including films,hydrogel,electrospun nanofibers,sponge,foam and three-dimension(3D)printed scaffold for skin regeneration,are elaborated discussed.Current challenges and the future perspectives are presented in thismultidisciplinary field.We envision that this review will provide a general insight to the elegant design and further refinement of wound dressing.

Development of polyurethane foam dressing containing silver and asiaticoside for healing of dermal wound

Polyurethane foam dressings for dermal wounds were formulated with natural polyols in order to improve the foam characteristics and the release of 2 active agents,silver and asiaticoside(AS)as an antimicrobial agent and an herbal wound healing agent,respectively.The foam was instantly formed by interaction of polyols and diisocyanate.Hydroxypropyl methylcellulose,chitosan and sodium alginate were individually mixed with themain polyols,polypropylene glycol,in the formulation while the active componentswere impregnated into the obtained foam dressing sheets.Although the type and amount of the natural polyols slightly affected the pore size,water sorption-desorption profile and compression strength of the obtained foam sheets,a prominent effect was found in the release of both active components.Among natural polyols formulations,foam sheets with alginate showed the highest silver and AS release.Non-cytotoxicity of these foam sheets to human fibroblast cells was confirmed.Antimicrobial testing on four bacteria strains showed that 1mg/cm^2 silver in formulations with 6%of natural polyols and without natural polyols had sufficient content of the silver release with comparable inhibition zone and significantly larger zone than other formulations.In pig study,the foam dressing with 6%alginate,1mg/cm^2 silver and 5%AS could improve wound healing in both the percentage of the wound closure and histological parameters of the dermal wound without any dermatologic reactions.In conclusion,this innovative foam dressing had potential to be a good candidate for wound treatment.

Molecular design, synthesis strategies and recent advances of hydrogels for wound dressing applications

With the changes in the modern disease spectrum,pressure ulcers,diabetic feet,and vascular-derived diseases caused refractory wounds is increasing rapidly.The development of wound dressings has partly improved the effect of wound management.However,traditional wound dressings can only cover the wound and block bacteria,but are generally powerless to recurrent wound infection and tissue healing.There is an urgent need to develop a new type of wound dressing with comprehensive performance to achieve multiple effects such as protecting the wound site from the external environment,absorbing wound exudate,anti-inflammatory,antibacterial,and accelerating wound healing process.Hydrogel wound dressings have the aforementioned characteristics,and can keep the wound in a moist environment because of the high water content,which is an ideal choice for wound treatment.This review introduces the wound healing process and the development and performance advantages of hydrogel wound dressings.The choice of different preparation materials gives the particularities of different hydrogel wound dressings.It also systematically explains the main physical and chemical crosslinking methods for hydrogel synthesis.Besides,in-depth discussion of four typical hydrogel wound dressings including double network hydrogels,nanocomposite hydrogels,drug-loaded hydrogels and smart hydrogels fully demonstrates the feasibility of developing hydrogels as wound dressing products and their future development trends.

On-machine Precision Preparation and Dressing of Ball-headed Diamond Wheel for the Grinding of Fused Silica

In the grinding of high quality fused silica parts with complex surface or structure using ball-headed metal bonded diamond wheel with small diameter,the existing dressing methods are not suitable to dress the ball-headed diamond wheel precisely due to that they are either on-line in process dressing which may causes collision problem or without consideration for the effects of the tool setting error and electrode wear.An on-machine precision preparation and dressing method is proposed for ball-headed diamond wheel based on electrical discharge machining.By using this method the cylindrical diamond wheel with small diameter is manufactured to hemispherical-headed form.The obtained ball-headed diamond wheel is dressed after several grinding passes to recover geometrical accuracy and sharpness which is lost due to the wheel wear.A tool setting method based on high precision optical system is presented to reduce the wheel center setting error and dimension error.The effect of electrode tool wear is investigated by electrical dressing experiments,and the electrode tool wear compensation model is established based on the experimental results which show that the value of wear ratio coefficient K’ tends to be constant with the increasing of the feed length of electrode and the mean value of K’ is 0.156.Grinding experiments of fused silica are carried out on a test bench to evaluate the performance of the preparation and dressing method.The experimental results show that the surface roughness of the finished workpiece is 0.03 μm.The effect of the grinding parameter and dressing frequency on the surface roughness is investigated based on the measurement results of the surface roughness.This research provides an on-machine preparation and dressing method for ball-headed metal bonded diamond wheel used in the grinding of fused silica,which provides a solution to the tool setting method and the effect of electrode tool wear.

Treating aplasia cutis congenita in a newborn with the combination of ionic silver dressing and moist exposed burn ointment: A case report

BACKGROUND Aplasia cutis congenita (ACC) in newborns is a condition in which congenital defects or hypoplasia is present in part of the epidermis,dermis and even subcutaneous tissue (including muscle and bones).First reported by Cordon in 1767,ACC is a rare disease with a low incidence of 1/100000 to 3/10000.Currently,there are 500 cases reported worldwide.ACC can be accompanied by other malformations.The onset mechanism of the disease remains unknown but is thought to be correlated to factors such as genetics,narrow uterus,foetal skin and amniotic membrane adhesion,use of teratogenic drugs in early pregnancy and viral infection.CASE SUMMARY In August 2018,we treated a newborn with ACC on the left lower limbs using a combination of ionic silver dressing and moist exposed burn ointment (MEBO) and achieved a satisfactory treatment outcome.The skin defects were observed on the external genitals and on areas from the left foot to 3/4 of the upper left side.Subcutaneous tissue and blood vessels were observed in the regions with skin defects.The following treatments were provided.First,the wound was rinsed with 0.9% sodium chloride solution followed by disinfection with povidone-iodine twice.And then MEBO was applied to the wound at a thickness of approximately 1 mm.After applying ionic silver dressing,the wound was covered with sterile gauze.The wound dressing was replaced every 2-3 d.At the 4-mo follow-up,the treatment outcome was satisfactory.There was minimal scar tissue formation,and limb function was not impaired.CONCLUSION The combination of ionic silver dressing and MEBO to ACC is helpful.

IN SlTU TRUING/DRESSING OF DIAMOND WHEEL FOR PRECISION GRINDING

An application for achieving on-machine truing/dressing and monitoring of diamond wheel is dealt with in dry grinding. A dry electrical discharge （ED） assisted truing and dressing method is adopted in preparation of diamond grinding wheels. Effective and precise truing/dressing of a diamond wheel is carried out on a CNC curve grinding machine by utilizing an ED assisted diamond dresser. The dressed wheel is monitored online by a CCD vision system. It detects the topography changes of a wheel surface. The wear condition is evaluated by analyzing the edge deviation of a wheel image. The benefits of the proposed methods are confirmed by the grinding experiments. The designed truing/dressing device has high material removal rate, low dresser wear, and hence guarantees a desired wheel surface. Real-time monitoring of the wheel profile facilitates determining the optimum dressing amount, dressing interval, and the compensation error.