Search results for: gelatinized chicken skin emulsion

Authors: Hailiang Liu, Yan Ni, Jie Zheng, Xiaoyan Jiang, Min Hong

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Allergic contact dermatitis (ACD) is a commonly clinical type IV allergic skin disease, with the pathological features of infiltration by mononuclear cells and tissue necrosis. Traditional Chinese medicine Radix Saposhnikoviae (RS) is traditionally employed to treat exogenous evils, rubella, itching, rheumatism and tetanus. Meanwhile, it is an important component of the commonly used anti-allergy compound. It’s now widely used as an immuno-modulating agent in mixed herbal decoctions to treat inflammation. However, its mechanism of anti-allergy remains unknown. RS was found to reduce ear thickness, as well as the infiltration of eosinophils. The proliferation of T lymphocytes was inhibited significantly by RS, markedly decreased IFN-γ levels in the supernatant of cells cultured and serum were detected with the treatment of RS. RS significantly decreased the amount of DCs in the mouse lymph nodes, and inhibited the expression of CD4 0 and CD86. Meanwhile, T-bet mRNA expression was down remarkably regulated by RS. These results indicate that RS cures Th1-induced allergic skin inflammation by regulating Th1/Th2 balance with decreasing Th1 differentiation, which might be associated with DCs.

Keywords: allergic contact dermatitis, Radix saposhnikoviae, dendritic cells, T-bet, GATA-3, CD4+ CD25+ Foxp3+ treg cells

Procedia PDF Downloads 357

Authors: Ch. Ramreddy, P. Naveen, D. Srinivasacharya

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The objective of the present study is to investigate the effect of nonlinear temperature and concentration on the mixed convective flow of micropolar fluid over an inclined flat plate in a non-Darcy porous medium in the presence of convective boundary condition. In order to analyze all the essential features, the transformed nonlinear conservation equations are worked out numerically by spectral method. By insisting the comparison between vertical, horizontal and inclined plates, the physical quantities of the flow and its characteristics are exhibited graphically and quantitatively with various parameters. An increase in the coupling number and inclination of angle tend to decrease the skin friction, mass transfer rate and the reverse change is there in wall couple stress and heat transfer rate. The nominal effect on the wall couple stress and skin friction is encountered whereas the significant effect on the local heat and mass transfer rates are found for high enough values of Biot number.

Keywords: convective boundary condition, micropolar fluid, non-darcy porous medium, non-linear convection, spectral method

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Authors: H. Niranjan, S. Sivasankaran

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Heat and mass transfer near a steady stagnation point boundary layer flow of viscous incompressible fluid through porous media investigates along a vertical plate is thoroughly studied under the presence of magneto hydrodynamic (MHD) effects. The fluid flow is steady, laminar, incompressible and in two-dimensional. The nonlinear differential coupled parabolic partial differential equations of continuity, momentum, energy and specie diffusion are converted into the non-similar boundary layer equations using similarity transformation, which are then solved numerically using the Runge-Kutta method along with shooting method. The effects of the conjugate heat transfer parameter, the porous medium parameter, the permeability parameter, the mixed convection parameter, the magnetic parameter, and the thermal radiation on the velocity and temperature profiles as well as on the local skin friction and local heat transfer are presented and analyzed. The validity of the methodology and analysis is checked by comparing the results obtained for some specific cases with those available in the literature. The various parameters on local skin friction, heat and mass transfer rates are presented in tabular form.

Keywords: MHD, porous medium, slip, convective boundary condition, stagnation point

Procedia PDF Downloads 284

Authors: Sitira Williams, Georgina Cherry, Andrea Wright, Kevin Wells, Taran Rai, Richard Brown, Travis Street, Alasdair Cook

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Social media sources (50) were identified, keywords defined by veterinarians and organised into 6 topics known to be indicative of feline pruritus: body areas, behaviors, symptoms, diagnosis, and treatments. These were augmented using academic literature, a cat owner survey, synonyms, and Google Trends. The content was collected using a social intelligence solution, with keywords tagged and filtered. Data were aggregated and de-duplicated. SL content matching body areas, behaviors and symptoms were reviewed manually, and posts were marked relevant if: posted by a pet owner, identifying an itchy cat and not duplicated. A sub-set of 493 posts published from 2009-2022 was used for reflexive thematic analysis in NVIVO (Burlington, MA) to identify themes. Five themes were identified: allergy, pruritus, additional behaviors, unusual or undesirable behaviors, diagnosis, and treatment. Most (258) posts reported the cat was excessively licking, itching, and scratching. The majority were indoor cats and were less playful and friendly when itchy. Half of these posts did not indicate a known cause of pruritus. Bald spots and scabs (123) were reported, often causing swelling and fur loss, and 56 reported bumps, lumps, and dry patches. Other impacts on the cat’s quality of life were ear mites, cat self-trauma and stress. Seven posts reported their cats’ symptoms caused them ongoing anxiety and depression. Cats with food allergies to poultry (often chicken and beef) causing bald spots featured in 23 posts. Veterinarians advised switching to a raw food diet and/or changing their bowls. Some cats got worse after switching, leaving owners’ needs unmet. Allergic reactions to flea bites causing excessive itching, red spots, scabs, and fur loss were reported in 13 posts. Some (3) posts indicated allergic reactions to medication. Cats with seasonal and skin allergies, causing sneezing, scratching, headshaking, watery eyes, and nasal discharge, were reported 17 times. Eighty-five posts identified additional behaviors. Of these, 13 reported their cat’s burst pimple or insect bite. Common behaviors were headshaking, rubbing, pawing at their ears, and aggressively chewing. In some cases, bites or pimples triggered previously unseen itchiness, making the cat irritable. Twenty-four reported their cat had anxiety: overgrooming, itching, losing fur, hiding, freaking out, breathing quickly, sleeplessness, hissing and vocalising. Most reported these cats as having itchy skin, fleas, and bumps. Cats were commonly diagnosed with an ear infection, ringworm, acne, or kidney disease. Acne was diagnosed in cats with an allergy flare-up or overgrooming. Ear infections were diagnosed in itchy cats with mites or other parasites. Of the treatments mentioned, steroids were most frequently used, then anti-parasitics, including flea treatments and oral medication (steroids, antibiotics). Forty-six posts reported distress following poor outcomes after medication or additional vet consultations. SL provides veterinarians with unique insights. Verbatim comments highlight the detrimental effects of pruritus on pets and owner quality of life. This study demonstrates the need for veterinarians to communicate management and treatment options more effectively to relieve owner frustrations. Data analysis could be scaled up using machine learning for topic modeling.

Keywords: content analysis, feline, itch, pruritus, social media, thematic analysis, veterinary dermatology

Procedia PDF Downloads 164

Authors: A. Beatti, L. Chipchase, A. Rayner, T. Souvlis

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The aims of this study were to investigate the depth of interferential current (IFC) penetration through soft tissue and to investigate the area over which IFC spreads during clinical application. Premodulated IFC and ‘true’ IFC at beat frequencies of 4, 40 and 90Hz were applied via four electrodes to the distal medial thigh of 15 healthy subjects. The current was measured via three Teflon coated fine needle electrodes that were inserted into the superficial layer of skin, then into the subcutaneous tissue (≈1 cm deep) and then into muscle tissue (≈2 cm deep). The needle electrodes were placed in the middle of the four IFC electrodes, between two channels and outside the four electrodes. Readings were taken at each tissue depth from each electrode during each treatment frequency then digitized and stored for analysis. All voltages were greater at all depths and locations than baseline (p < 0.01) and voltages decreased with depth (P=0.039). Lower voltages of all currents were recorded in the middle of the four electrodes with the highest voltage being recorded outside the four electrodes in all depths (P=0.000).For each frequency of ‘true’ IFC, the voltage was higher in the superficial layer outside the electrodes (P ≤ 0.01).Premodulated had higher voltages along the line of one circuit (P ≤ 0.01). Clinically, IFC appears to pass through skin layers to depth and is more efficient than premodulated IFC when targeting muscle tissue.

Keywords: electrotherapy, interferential current, interferential therapy, medium frequency current

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Authors: Mona Nada, Fahmy Fahmy

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Background: Pleomorphic dermal sarcoma is a rare form of skin cancer affecting cutaneous layer and, in some cases associated with recurrence and metastasis, very commonly to seen in elderly patient affecting the area of head and neck. Pleomorphic dermal sarcoma rises in ultraviolet light exposed areas. The symptoms and severity of this kind of skin cancer varies according to histological factors. The differentiation of Pleomorphic dermal sarcoma needs extensive immunohistochemistry, as the diagnosis depends mainly on exclusion to rule out other malignancy like poorly differentiated squamous cell carcinoma, melanoma, angiosarcoma and leiomyosarcoma. Objective: assessing the management of Pleomorphic dermal sarcoma in our unit and compared to the updated guidelines. Design: Retrospective study Collection of patient data from medical records at countess of Chester plastic surgery unit of the last 5 years, all histologically confirmed Pleomorphic dermal sarcoma (2017-2023). Data were collected confirmed to be Pleomorphic dermal sarcoma were included in the study. The data collected: clinical description of the lesions at first presentation, operation time, multidisciplinary team discussion, plan, referral as well as second operation and investigation done. With comparison of histological examination, immunohistochemistry staining, the excision and rate of recurrence. Results: data collected N19 from (2017-2023) showed the disease predominantly affecting males and the lesion mainly in head and neck, the diagnosis needed extensive immunohistochemistry to differentiate between other malignancy. recurrence present in numbers of the cases which managed after multidisciplinary team discussion either by excision or radiotherapy. Conclusion: Pleomorphic dermal sarcoma is a rare malignancy which needs more understanding and avoid missing as it is aggressive form of skin cancer, there is a chance of metastasis and recurrence which makes it very important to understand the process of development of the cancer and frequent review of the management guidelines.

Keywords: pleomorphic dermal sarcoma, recurrence, radiotherapy, surgical

Procedia PDF Downloads 51

Authors: Azza Hashim Abbas, Wan Rosli Wan Suliman

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The old school of study, well testing reservoir engineers used the transient pressure analyses to get certain parameters and variable factors on the reservoir's physical properties, such as, (permeability-thickness). Recently, the difficulties facing the newly discovered areas are the convincing fact that the exploration and production (E&p) team should have sufficiently accurate and appropriate data to work with due to different sources of errors. The well-test analyst does the work without going through well-informed and reliable data from colleagues which may consequently cause immense environmental damage and unnecessary financial losses as well as opportunity losses to the project. In 2003, new potential oil field (Moga) face circulation problem well-22 was safely completed. However the high mud density had caused an extensive damage to the nearer well area which also distracted the hypothetical oil rate of flow that was not representive of the real reservoir characteristics This paper presents methods to analyze and interpret the production rate and pressure data of an oil field. Specifically for Well- 22 using the Deconvolution technique to enhance the transient pressure .Applying deconvolution to get the best range of certainty of results needed for the next subsequent operation. The range determined and analysis of skin factor range was reasonable.

Keywords: well testing, exploration, deconvolution, skin factor, un certainity

Procedia PDF Downloads 426

Authors: N. N. Mosola, S. J. Molete, L. S. Masoebe, M. Letsae

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Hand gesture recognition is a technique used to locate, detect, and recognize a hand gesture. Detection and recognition are concepts of Artificial Intelligence (AI). AI concepts are applicable in Human Computer Interaction (HCI), Expert systems (ES), etc. Hand gesture recognition can be used in sign language interpretation. Sign language is a visual communication tool. This tool is used mostly by deaf societies and those with speech disorder. Communication barriers exist when societies with speech disorder interact with others. This research aims to build a hand recognition system for Lesotho’s Sesotho and English language interpretation. The system will help to bridge the communication problems encountered by the mentioned societies. The system has various processing modules. The modules consist of a hand detection engine, image processing engine, feature extraction, and sign recognition. Detection is a process of identifying an object. The proposed system uses Canny pruning Haar and Haarcascade detection algorithms. Canny pruning implements the Canny edge detection. This is an optimal image processing algorithm. It is used to detect edges of an object. The system employs a skin detection algorithm. The skin detection performs background subtraction, computes the convex hull, and the centroid to assist in the detection process. Recognition is a process of gesture classification. Template matching classifies each hand gesture in real-time. The system was tested using various experiments. The results obtained show that time, distance, and light are factors that affect the rate of detection and ultimately recognition. Detection rate is directly proportional to the distance of the hand from the camera. Different lighting conditions were considered. The more the light intensity, the faster the detection rate. Based on the results obtained from this research, the applied methodologies are efficient and provide a plausible solution towards a light-weight, inexpensive system which can be used for sign language interpretation.

Keywords: canny pruning, hand recognition, machine learning, skin tracking

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Authors: Hala M. El-hanbuli, Mohammed F. Darweesh

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The incidence rates of any tumor vary hugely with geographical location. Basal Cell Carcinoma (BCC) is one of the most common skin cancer that has many histopathologic subtypes. Objective: The aim was to study the histopathological features of BCC cases that were received in the Pathology Department, Kasr El-Aini hospital, Cairo University, Egypt during the period from Jan 2004 to Dec 2013 and to evaluate the clinical characters through the patient data available in the request sheets. Methods: Slides and data of BCC cases were collected from the archives of the pathology department, Kasr El-Aini hospital. Revision of all available slides and histological classification of BCC according to WHO (2006) was done. Results: A total number of 310 cases of BCC representing about 65% from the total number of malignant skin tumors examined during the 10-years duration in the department. The age ranged from 8 to 84 years, the mean age was (55.7 ± 15.5). Most of the patients (85%) were above the age of 40 years. There was a slight male predominance (55%). Ulcerated BCC was the most common gross picture (60%), followed by nodular lesion (30%) and finally the ulcerated nodule (10%). Most of the lesions situated in the high-risk sites (77%) where the nose was the most common site (35%) followed by the periocular area (22%), then periauricular (15%) and finally perioral (5%). No lesion was reported outside the head. The tumor size was less than 2 centimeters in 65% of cases, and from 2-5 centimeters in the lesions' greatest dimension in the rest of cases. Histopathological reclassification revealed that the nodular BCC was the most common (68%) followed by the pigmented nodular (18.75%). The histologic high-risk groups represented (7.5%) about half of them (3.75%) being basosquamous carcinoma. The total incidence for multiple BCC and 2nd primary was 12%. Recurrent BCC represented 8%. All of the recurrent lesions of BCC belonged to the histologic high-risk group. Conclusion: Basal Cell Carcinoma is the most common skin cancer in the 10-year survey. Histopathological diagnosis and classification of BCC cases are essential for the determination of the tumor type and its biological behavior.

Keywords: basal cell carcinoma, high risk, histopathological features, statistical analysis

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Authors: Silvia Ximena Barrios, Diego Armando Villamizar Mantilla, Raquel Elvira Ocazionez, , Elena E. Stashenko, María Pilar Vinardell, Jorge Luis Fuentes

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Introduction: Skin overexposure to solar radiation has been a serious public health concern, because of its potential carcinogenicity. Therefore, preventive protection strategies using photoprotective agents are critical to counteract the harmful effect of solar radiation. Plants may be a source of photoprotective compounds that inhibit cellular mutations involved in skin cancer initiation. This work evaluated the photoprotective and antigenotoxic effects against ultraviolet B (UVB) radiation of a mixture of Posoqueria latifolia flower extract and Kaempferol (MixPoKa). Methods: The photoprotective efficacy of MixPoka (Posoqueria latifolia flower extract 250 μg/ml and Kaempferol 349.5 μM) was evaluated using in vitro indices such as sun protection factor SPFᵢₙ ᵥᵢₜᵣₒ and critical wavelength (λc). The MixPoKa photostability (Eff) at human minimal erythema doses (MED), according to the Fitzpatrick skin scale, was also estimated. Cytotoxicity and genotoxicity/antigenotoxicity were studied in MRC5 human fibroblasts using the trypan blue exclusion and Comet assays, respectively. Kinetics of the genetic damage repair post irradiation in the presence and absence of the MixPoka, was also evaluated. Results: The MixPoka -UV absorbance spectrum was high across the spectral bands between 200 and 400 nm. The UVB photoprotection efficacy of MixPoka was high (SPFᵢₙ ᵥᵢₜᵣₒ = 25.70 ± 0.06), showed wide photoprotection spectrum (λc = 380 ± 0), and resulted photostable (Eff = 92.3–100.0%). The MixPoka was neither cytotoxic nor genotoxic in MRC5 human fibroblasts; but presented significant antigenotoxic effect against UVB radiation. Additionally, MixPoka stimulate DNA repair post-irradiation. The potential of this phytochemical mixture as sunscreen ingredients was discussed. Conclusion: MixPoka showed a significant antigenotoxic effect against UVB radiation and stimulated DNA repair after irradiation. MixPoka could be used as an ingredient in a sunscreen cream.

Keywords: flower extract, photoprotection, antigenotoxicity, cytotoxicity, genotoxicit

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Authors: Emmanuelle Merat, Arnaud Aubert, Sophie Cambos, Francis Vial, Patrick Beau

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Basically, consumers are sensitive to many stimuli when applying a cream: brand, packaging and indeed formulation compositions. Many studies demonstrated the influence of some stimuli such as brand, packaging, formula color and odor (e.g. in make-up applications). Those parameters influence perceived quality of the product. The objective of this work is to further investigate the relationship between nude skincare basic compositions with different textures and consumer experience. A tentative final step will be to connect the consumer feelings with key ingredients in the compositions. A new approach was developed to better understand touch-related subjective experience in consumers based on a combination of methods: sensory analysis with ten experts, preference mapping on one hundred female consumers and emotional assessments on thirty consumers (verbal and non-verbal through prosody and gesture monitoring). Finally, a methodology based on ‘sensorial trip’ (after olfactory, haptic and musical stimuli) has been experimented on the most interesting textures with 10 consumers. The results showed more or less impact depending on compositions and also on key ingredients. Three types of formulation particularly attracted the consumer: an aqueous gel, an oil-in-water emulsion, and a patented gel-in-oil formulation type. Regarding these three formulas, the preferences were both revealed through sensory and emotion tests. One was recognized as the most innovative in consumer sensory test whereas the two other formulas were discriminated in emotions evaluation. The positive emotions were highlighted especially in prosody criteria. The non-verbal analysis, which corresponds to the physical parameters of the voice, showed high pitch and amplitude values; linked to positive emotions. Verbatim, verbal content of responses (i.e., ideas, concepts, mental images), confirmed the first conclusion. On the formulas selected for their positive emotions generation, the ‘sensorial trip’ provided complementary information to characterize each emotional profile. In the second step, dedicated to better understand ingredients power, two types of ingredients demonstrated an obvious input on consumer preference: rheology modifiers and emollients. As a conclusion, nude cosmetic compositions with well-chosen textures and ingredients can positively stimulate consumer emotions contributing to capture their preference. For a complete achievement of the study, a global approach (Asia, America territories...) should be developed.

Keywords: sensory, emotion, cosmetic formulations, ingredients' influence

Procedia PDF Downloads 158

Authors: Sanjay Saraf

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The oral cavity can be the site for early manifestations of mucocutaneous disorders (MD) or the only site for occurrence of these disorders. It can also exhibit oral lesions with simultaneous associated skin lesions. The MD involving the oral mucosa commonly presents with signs such as ulcers, vesicles and bullae. The unique environment of the oral cavity may modify these signs of the disease, thereby making the clinical diagnosis an arduous task. In addition to the unique environment of oral cavity, the overlapping of the signs of various mucocutaneous disorders, also makes the clinical diagnosis more intricate. The aim of this review is to present the oral signs of dermatological disorders having common oral involvement and emphasize their importance in early detection of the systemic disorders. The aim is also to highlight the necessity of oral examination by a dermatologist while examining the skin lesions. Prior to the oral examination, it must be imperative for the dermatologists and the dental clinicians to have the knowledge of oral anatomy. It is also important to know the impact of various diseases on oral mucosa, and the characteristic features of various oral mucocutaneous lesions. An initial clinical oral examination is may help in the early diagnosis of the MD. Failure to identify the oral manifestations may reduce the likelihood of early treatment and lead to more serious problems. This paper reviews the oral manifestations of immune mediated dermatological disorders with common oral manifestations.

Keywords: dermatological investigations, genodermatosis, histological features, oral examination

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Authors: Egoitz Aldanondo, Ekaitz Arruti, Amaia Iturrioz, Ivan Huarte, Fidel Zubiri

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Manufacturing aeronautic structures joining extruded profiles or stringers to sheets or skins of aluminium is a typical manufacturing procedure in aeronautic structures. Although riveting is the conventional manufacturing technology to produce such joints, the Friction Stir Welding (FSW) and Laser Beam Welding (LBW) technologies have also demonstrated their potential for this kind of applications. Therefore, FSW and LBW technologies have the potential to continue their development as manufacturing processes for aeronautic structures showing benefits such as time-saving, light-weighting and overall cost reduction. In addition to that, new aluminium-lithium based alloy developments represent great opportunities for advanced aeronautic structure manufacturing with potential benefits such as lightweight construction or improved corrosion resistance. This work presents the main approaches by FSW and LBW to develop those technologies to produce stiffened panel structures such as fuselage by stringer-skin joints and using innovative aluminium-lithium alloys. Initial welding tests were performed in AA2198-T3S aluminium alloys for LBW technology and with AA2198-T851 for FSW. Later tests for both FSW and LBW have been carried out using AA2099-T83 alloy extrusions as stringers and AA2060-T8E30 as skin materials. The weld quality and properties have been examined by metallographic analysis and mechanical testing, including shear tensile tests and pull-out tests. The analysis of the results have shown the relationships between processing conditions, micro-macrostructural properties and the mechanical strength of the welded joints. The effects produced in the different alloys investigated have been observed and particular weld formation mechanics have been studied for each material and welding technology. Therefore, relationships between welding conditions and the obtained weld properties for each material combination and welding technology will be discussed in this presentation.

Keywords: AA2060-T8E30, AA2099-T83, AA2198-T3S, AA2198-T851, friction stir welding, laser beam welding

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Authors: Amanpreet Kaur, Ravinder Agarwal, Amod Kumar

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Surface electromyography is a strategy to measure the muscle activity of the skin. Sensors placed on the skin recognize the electrical current or signal generated by active muscles. A lot of the research has focussed on the detection of signal from upper limb amputee with activity of triceps and biceps muscles. The purpose of this study was to correlate phantom movement and sEMG activity in residual stump muscles of transhumeral amputee from the shoulder muscles. Eight non- amputee and seven right hand amputees were recruited for this study. sEMG data were collected for the trapezius, pectoralis and teres muscles for elevation, protraction and retraction of shoulder. Contrast between the amputees and non-amputees muscles action have been investigated. Subsequently, to investigate the impact of class separability for different motions of shoulder, analysis of variance for experimental recorded data was carried out. Results were analyzed to recognize different shoulder movements and represent a step towards the surface electromyography controlled system for amputees. Difference in F ratio (p < 0.05) values indicates the distinction in mean therefore these analysis helps to determine the independent motion. The identified signal would be used to design more accurate and efficient controllers for the upper-limb amputee for researchers.

Keywords: around shoulder amputation, surface electromyography, analysis of variance, features

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Authors: Ikram Mohamed Eltayeb Elsiddig, Abdel Khalig Muddather, Hiba Abdel Rahman Ali, Saad Mohamed Hussein Ayoub

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Anogeissusleiocarpus (Combretaceae) is well known for its medicinal uses in African traditional medicine, for treating many human diseases mainly skin diseases and infections.Mycetoma disease is a fungal and/ or bacterial skin infection, mainly cause by Madurella mycetomatis fungus.This study was carried out in vitro to investigate the antifungal activity of Anogeissusleiocarpus leaf extracts against the isolated pathogenicMadurellamycetomatis, by using the NCCLS modified method compared to Ketoconazole standard drug and MTT assay. The bioactive fraction was subjected to chemical analysis implementing different chromatographic analytical methods (TLC, HPLC, and LC-MS/MS). The results showed significance antifungal activity of A. leiocarpus leaf extractsagainst the isolated pathogenicM. mycetomatis, compared to negative and positive controls. The chloroform fraction showed the highest antifungal activity.The chromatographic analysis of the chloroform fraction with the highest activity showed the presence of important bioactive compounds such as ellagic and flavellagic acids derivatives, flavonoids and stilbenoid, which are well known for their antifungal activity.

Keywords: Anogeissus leiocarpus, crude extracts and fractions of Anogeissus leiocarpus, in vitrosusceptibility of Madurella mycetomatis, Madurella mycetomatis

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Authors: Caspar S. Carson, Gabriel W. Prather, Nicholas E. Wong, Jeffery R. Anton, William H. McCoy

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Cutibacterium acnes is a commensal bacterium found on human skin that has been linked to acne. C. acnes can also be an opportunistic pathogen when it infiltrates the body during surgery. This pathogen can cause dangerous infections of medical implants, such as shoulder replacements, leading to life-threatening blood infections. Compounding this issue, C. acnes resistance to many antibiotics has become an increasing problem worldwide, creating a need for special forms of treatment. C. acnes expresses the protein RoxP, and it requires this protein to colonize human skin. Though this protein is required for C. acnes skin colonization, its function is not yet understood. Inhibition of RoxP function might be an effective treatment for C. acnes infections. To develop such reagents, the McCoy Laboratory generated four unique anti-RoxP antibodies. Preliminary studies in the McCoy Lab have established that each antibody binds a distinct site on RoxP. To assess the potential of these antibodies as therapeutics, it is necessary to specifically characterize these antibody epitopes and evaluate them in assays that assess their ability to inhibit RoxP-dependent C. acnes growth. To provide material for these studies, an antibody expression construct, Fv-clasp(v2), was adapted to encode anti-RoxP antibody sequences. The author hypothesizes that this expression strategy can produce sufficient amounts of >95% pure antibody fragments for further characterization of these antibodies. Four anti-RoxP Fv-clasp(v2) expression constructs (pET vector-based) were transformed into E. coli BL21-Gold(DE3) cells and a small-scale expression and purification trial was performed for each construct to evaluate anti-RoxP Fv-clasp(v2) yield and purity. Successful expression and purification of these antibody constructs will allow for their use in structural studies, such as protein crystallography and cryogenic electron microscopy. Such studies would help to define the antibody binding sites on RoxP, which could then be leveraged in the development of certain methods to treat C. acnes infection through RoxP inhibition.

Keywords: structural biology, protein expression, infectious disease, antibody, therapeutics, E. coli

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Authors: Carolina L. Cerdeira, Julia V. F. Cortes, Maria E. V. Amarante, Gersika B. Santos

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Skin cancer is the most common cancer in several parts of the world; in a tropical country like Brazil, the situation isn’t different. The Brazilian population is exposed to high levels of solar radiation, increasing the risk of developing cutaneous carcinoma. Aimed at encouraging prevention measures and the early diagnosis of these tumors, a study was carried out that analyzed data on cutaneous melanomas, basal cell, and epidermoid carcinomas, using as primary data source the medical records of 161 patients registered in one pathology service, which performs skin biopsies in a city of Minas Gerais, Brazil. All patients diagnosed with skin cancer at this service from January 2015 to December 2019 were included. The incidence of skin carcinoma cases was correlated with the identification of histological type, sex, age group, and topographic location. Correlation between variables was verified by Fisher's exact test at a nominal significance level of 5%, with statistical analysis performed by R® software. A significant association was observed between age group and type of cancer (p=0.0085); age group and sex (0.0298); and type of cancer and body region affected (p < 0.01). Those 161 cases analyzed comprised 93 basal cell carcinomas, 66 epidermoid carcinomas, and only two cutaneous melanomas. In the group aged 19 to 30 years, the epidermoid form was most prevalent; from 31 to 45 and from 46 to 59 years, the basal cell prevailed; in 60-year-olds or over, both types had higher frequencies. Associating age group and sex, in groups aged 18 to 30 and 46 to 59 years, women were most affected. In the 31-to 45-year-old group, men predominated. There was a gender balance in the age group 60-year-olds or over. As for topography, there was a high prevalence in the head and neck, followed by upper limbs. Relating histological type and topography, there was a prevalence of basal cell and epidermoid carcinomas in the head and neck. In the chest, the basal cell form was most prevalent; in upper limbs, the epidermoid form prevailed. Cutaneous melanoma affected only the chest and upper limbs. About 82% of patients 60-year-olds or over had head and neck cancer; from 46 to 59 and 60-year-olds or over, the head and neck region and upper limbs were predominantly affected; the distribution was balanced in the 31-to 45-year-old group. In conclusion, basal cell carcinoma was predominant, whereas cutaneous melanoma was the rarest among the types analyzed. Patients 60-year-olds or over were most affected, showing gender balance. In young adults, there was a prevalence of the epidermoid form; in middle-aged patients, basal cell carcinoma was predominant; in the elderly, both forms presented with higher frequencies. There was a higher incidence of head and neck cancers, followed by malignancies affecting the upper limbs. The epidermoid type manifested significantly in the upper limbs. Body regions such as the thorax and lower limbs were less affected, which is justified by the lower exposure of these areas to incident solar radiation.

Keywords: basal cell carcinoma, cutaneous melanoma, skin cancer, squamous cell carcinoma, topographic location

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Authors: Chih-Yang Liao

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Baseball is usually played outdoors in the warmest months of the year. Therefore, baseball players are susceptible to the influence of the hot environment. It has been shown that hitting performance is increased in games played in warm weather, compared to in cold weather, in Major League Baseball. Intermittent cooling during sporting events can prevent the risk of hyperthermia and increase endurance performance. However, the effects of cooling during baseball games played in a hot environment are unclear. This study adopted a cross-over design. Ten Division I collegiate male baseball players in Taiwan volunteered to participate in this study. Each player played two simulated baseball games, with one day in between. Five of the players received intermittent cooling during the first simulated game, while the other five players received intermittent cooling during the second simulated game. The participants were covered in neck and forehand regions for 6 min with towels that were soaked in icy salt water 3 to 4 times during the games. The participants received the cooling treatment in the dugout when they were not on the field for defense or hitting. During the 2 simulated games, the temperature was 31.1-34.1°C and humidity was 58.2-61.8%, with no difference between the two games. Ratings of perceived exertion, thermal sensation, tympanic and forehead skin temperature immediately after each defensive half-inning and after cooling treatments were recorded. Ratings of perceived exertion were measured using the Borg 10-point scale. The thermal sensation was measured with a 6-point scale. The tympanic and skin temperature was measured with infrared thermometers. The data were analyzed with a two-way analysis of variance with repeated measurement. The results showed that intermitted cooling significantly reduced ratings of perceived exertion and thermal sensation. Forehead skin temperature was also significantly decreased after cooling treatments. However, the tympanic temperature was not significantly different between the two trials. In conclusion, intermittent cooling in the neck and forehead regions was effective in alleviating the perceived exertion and heat sensation. However, this cooling intervention did not affect the core temperature. Whether intermittent cooling has any impact on hitting or pitching performance in baseball players warrants further investigation.

Keywords: baseball, cooling, ratings of perceived exertion, thermal sensation

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Authors: Emily Moore, Dora Amos, Tracy Ellimah, Natasha Parrott

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Postoperative haematoma is a well-recognised complication of thyroid surgery with an incidence of 1-5%. Haematoma formation causes progressive airway obstruction, necessitating emergency bedside haematoma evacuation in up to ¼ of patients. ENT UK, BAETS and DAS have developed consensus guidelines to improve perioperative care, recommending that all healthcare staff interacting with patients undergoing thyroid surgery should be trained in managing post-thyroidectomy haematoma. The aim was to assess the effectiveness of a hybrid simulation model in improving clinician’s confidence in dealing with this surgical emergency. A hybrid simulation was designed, consisting of a standardised patient wearing a part-task trainer to mimic a post-thyroidectomy haematoma in a real patient. The part-task trainer was an adapted C-spine collar with layers of silicone representing the skin and strap muscles and thickened jelly representing the haematoma. Both the skin and strap muscle layers had to be opened in order to evacuate the haematoma. Boxes have been implemented into the appropriate post operative areas (recovery and surgical wards), which contain a printed algorithm designed to assist in remembering a sequence of steps for haematoma evacuation using the ‘SCOOP’ method (skin exposure, cut sutures, open skin, open muscles, pack wound) along with all the necessary equipment to open the front of the neck. Small-group teaching sessions were delivered by ENT and anaesthetic trainees to members of the multidisciplinary team normally involved in perioperative patient care, which included ENT surgeons, anaesthetists, recovery nurses, HCAs and ODPs. The DESATS acronym of signs and symptoms to recognise (difficulty swallowing, EWS score, swelling, anxiety, tachycardia, stridor) was highlighted. Then participants took part in the hybrid simulation in order to practice this ‘SCOOP’ method of haematoma evacuation. Participants were surveyed using a Likert scale to assess their level of confidence pre- and post teaching session. 30 clinicians took part. Confidence (agreed/strongly agreed) in recognition of post thyroidectomy haematoma improved from 58.6% to 96.5%. Confidence in management improved from 27.5% to 89.7%. All participants successfully decompressed the haematoma. All participants agreed/strongly agreed, that the sessions were useful for their learning. Multidisciplinary team simulation teaching is effective at significantly improving confidence in both the recognition and management of postoperative haematoma. Hybrid simulation sessions are useful and should be incorporated into training for clinicians.

Keywords: thyroid surgery, haematoma, teaching, hybrid simulation

Procedia PDF Downloads 78

Authors: Maria E. V. Amarante, Carolina L. Cerdeira, Julia V. Cortes, Fiorita G. L. Mundim

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Basal cell carcinoma (BCC) is the most prevalent type of skin cancer in humans. It arises from the basal cells of the epidermis and cutaneous appendages. The role of sunlight exposure as a risk factor for BCC is very well defined due to its power to influence genetic mutations, in addition to having a suppressor effect on the skin immune system. Despite showing low metastasis and mortality rates, the tumor is locally infiltrative, aggressive, and destructive. Considering the high prevalence rate of this carcinoma and the importance of early detection, a retrospective study was carried out in order to correlate the clinical data available on BBC, characterize it epidemiologically, and thus enable effective prevention measures for the population. Data on the period from January 2015 to December 2019 were collected from the medical records of patients registered at one pathology service located in the southeast region of Brazil, known as SVO, which delivers skin biopsy results. The study was aimed at correlating the variables, sex, age, and subtypes found. Data analysis was performed using the chi-square test at a nominal significance level of 5% in order to verify the independence between the variables of interest. Fisher's exact test was applied in cases where the absolute frequency in the cells of the contingency table was less than or equal to five. The statistical analysis was performed using the R® software. Ninety-three basal cell carcinoma were analyzed, and its frequency in the 31-to 45-year-old age group was 5.8 times higher in men than in women, whereas, from 46 to 59 years, the frequency was found 2.4 times higher in women than in men. Between the ages of 46 to 59 years, it should be noted that the sclerodermiform subtype appears more than the solid one, with a difference of 7.26 percentage points. Reversely, the solid form appears more frequently in individuals aged 60 years or more, with a difference of 8.57 percentage points. Among women, the frequency of the solid subtype was 9.93 percentage points higher than the sclerodermiform frequency. In males, the same percentage difference is observed, but sclerodermiform is the most prevalent subtype. It is concluded in this study that, in general, there is a predominance of basal cell carcinoma in females and in individuals aged 60 years and over, which demonstrates the tendency of this tumor. However, when rarely found in younger individuals, the male gender prevailed. The most prevalent subtype was the solid one. It is worth mentioning that the sclerodermiform subtype, which is more aggressive, was seen more frequently in males and in the 46-to 59-year-old range.

Keywords: basal cell carcinoma, epidemiology, sclerodermiform basal cell carcinoma, skin cancer, solar radiation, solid basal cell carcinoma

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Authors: Phakamani Xaba, Robert Huberts, Bilainu Oboirien

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It has been over 200 years since margarine was discovered and manufactured using liquid oil, liquified hardstock oils and other oil phase & aqueous phase ingredients. Henry W. Bradley first used vegetable oils in liquid state and around 1871, since then; spreads have been traditionally manufactured using liquified oils. The main objective of this study was to develop a process method to produce spreads using spray dried hardstock fat powders as a structing fats in place of current liquid structuring fats. A high shear mixing system was used to condition the fat phase and the aqueous phase was prepared separately. Using a single scraped surface heat exchanger and pin stirrer, margarine was produced. The process method was developed for to produce spreads with 40%, 50% and 60% fat . The developed method was divided into three steps. In the first step, fat powders were conditioned by melting and dissolving them into liquid oils. The liquified portion of the oils were at 65 °C, whilst the spray dried fat powder was at 25 °C. The two were mixed using a mixing vessel at 900 rpm for 4 minutes. The rest of the ingredients i.e., lecithin, colorant, vitamins & flavours were added at ambient conditions to complete the fat/ oil phase. The water phase was prepared separately by mixing salt, water, preservative, acidifier in the mixing tank. Milk was also separately prepared by pasteurizing it at 79°C prior to feeding it into the aqueous phase. All the water phase contents were chilled to 8 °C. The oil phase and water phase were mixed in a tank, then fed into a single scraped surface heat exchanger. After the scraped surface heat exchanger, the emulsion was fed in a pin stirrer to work the formed crystals and produce margarine. The margarine produced using the developed process had fat levels of 40%, 50% and 60%. The margarine passed all the qualitative, stability, and taste assessments. The scores were 6/10, 7/10 & 7.5/10 for the 40%, 50% & 60% fat spreads, respectively. The success of the trials brought about differentiated knowledge on how to manufacture spreads using non micronized spray dried fat powders as hardstock. Manufacturers do not need to store structuring fats at 80-90°C and even high in winter, instead, they can adapt their processes to use fat powders which need to be stored at 25 °C. The developed process method used one scrape surface heat exchanger instead of the four to five currently used in votator based plants. The use of a single scraped surface heat exchanger translated to about 61% energy savings i.e., 23 kW per ton of product. Furthermore, it was found that the energy saved by implementing separate pasteurization was calculated to be 6.5 kW per ton of product produced.

Keywords: margarine emulsion, votator technology, margarine processing, scraped sur, fat powders

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Authors: M. Safiqul Islam, Md Arafat Hossain Sarkar

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Brachytherapy is one of the most important cancer treatment management systems in radiotherapy department. Brachytherapy treatment is moved into High Dose Rate (HDR) after loader from Low Dose Rate (LDR) after loader due to radiation protection advantage. HDR Brachytherapy is a highly multipurpose system for enhancing cure and achieving palliation in many common cancers disease of developing countries. High-dose rate (HDR) Brachytherapy is a type of internal radiation therapy that delivers radiation from implants placed close to or inside, the tumor(s) in the body. This procedure is very effective at providing localized radiation to the tumor site while minimizing the patient’s whole body dose. Brachytherapy has proven to be a highly successful treatment for cancers of the prostate, cervix, endometrium, breast, skin, bronchus, esophagus, and head and neck, as well as soft tissue sarcomas and several other types of cancer. For the time being in our country we have 10 new HDR Remote after loading Brachytherapy. Right now 4 HDR Brachytherapy is already installed and running for patient’s treatment out of 10 HDR Brachytherapy. Ir-192 source is more comfortable than Co-60. In that case people or expert personnel prefer Ir-192 source for different kind of cancer patients. Ir-192 are economically, more flexible and familiar in our country.

Keywords: Ir-192, brachytherapy, cancer treatment, prostate, cervix, endometrium, breast, skin, bronchus, esophagus, soft tissue sarcomas

Procedia PDF Downloads 408

Authors: Soheir Weheida, Amal E. Shehata, Samira E. Aboalizm

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The aim of this study was to examine the effect of surgical safety checklist on surgical team’s knowledge and performance in operating room. Subjects: A convenience sample 151 (48 head nurse, 45 nurse, 37 surgeon and 21 anesthesiologist) which available in operating room at two different hospitals was included in the study. Setting: The study was carried out at operating room in Menoufia University and Shebin Elkom Teaching Hospitals, Egypt. Tools: I: Surgical safety: Surgical team knowledge assessment structure interview schedule. II: WHO surgical safety observational Checklist. III: Post Surgery Culture Survey scale. Results: There was statistical significant improvement of knowledge mean score and performance about surgical safety especially in post and follow up than pre intervention, before patients entering the operating, before induction of anesthesia, skin incision and post skin closure and before patient leaves operating room, P values (P < 0.001). Improvement of communication post intervention than pre intervention between surgical team’s (4.74 ± 0.540). About two thirds (73.5 %) of studied sample strongly agreed on surgical safety in operating room. Conclusions: Implementation of surgical safety checklist has a positive effect on improving knowledge, performance and communication between surgical teams and these seems to have a positive effect on improve patient safety in the operating room.

Keywords: knowledge, operating room, performance, surgical safety checklist

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Authors: Umran Erciyes, Filiz Okumus

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The purpose of this study was the determination of factors which impact the pregnancy, birth experience and the opinions regarding the delivery type of the puerperants, after vaginal birth. This descriptive study includes 349 patients who gave births with normal birth in one of the hospital in İstanbul in May- November 2014. After birth, we interview with these women face to face. The descriptive information form and Perception of Birth Scale were used as data collection tool. SPSS (Statistical Package for the Social Sciences) was used for statistical analysis. The average age of patients was 27.13, and the average score was 76.93±20.22. The patients are primary school graduate, and they do not have a job. They expressed an income outcome equality. More than half of women did not get educated before birth. Among educated patients, few women got educated overcoming the pain during labor process. As the time spent in the hospital for the birth increases, the birth perception of mothers is affected negatively. %86.8 of participants gave assisted delivery. Spontaneous vaginal birth has positive effects on birth perception. Establishing a vascular access, induction of labor performing enema, restriction of orally intake and movement, fundal pressure, episiotomy, nor to perform skin to skin contact with the baby after birth has adverse effects on the birth perceptions.

Keywords: antenatal care, birth experience, perception of birth, vaginal birth

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Authors: Nandita Ghosh, Shinjini Mitra, Ena Ray Banerjee

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Atopic dermatitis (AD) is a chronic disease of the skin, involving itchy, reddish, and scaly lesions. It mainly affects children and has a high prevalence in developing countries. The AD may occur due to environmental or genetic factors. There is no permanent cure for the AD. Currently, all therapeutic strategies involve methods to simply alleviate the symptoms, and include lotions and corticosteroids, which have adverse effects. Use of phytochemicals and natural products has not yet been exploited fully. The particle used in this study is derived from Cyamopsis tetragonoloba, an edible polysaccharide with a galactomannan component. The mannose component mainly increases its specificity towards cellular uptake by mannose receptors, highly expressed by the macrophage. The aim of this study was to determine the therapeutic effect of guar gum nanoparticles (GN) in vitro and in vivo in the AD. To assess the wound healing capacity of the guar gum nanoparticle (GN), we first treated adherent NIH3T3 cells, with a scratch injury, with GN. GN successfully healed the wound caused by the scratch. In the in vivo experiment, Balb/c mice ear were topically treated with oxazolone (oxa) to induce AD and then were topically treated with GN. The ear thickness was increased significantly till day 28 on the treatment of Oxa. The GN application showed a significant decrease in the thickness as assessed on day 28. The total cell count of skin cells showed fold increase when treated with oxa, was again decreased on topical application of GN on the affected skin. The eosinophil count, as assessed by Giemsa staining was also increased when treated with oxa, GN application led to a significant decrease. The IgE level was assessed in the serum samples which showed that GN helped in restoring the alleviated IgE level. The T helper cells and the macrophage population showed increased percentage when treated with oxa, the GN application. This was examined by flow cytometry. The H&E staining of the ear tissue showed epidermal thickness in the oxa treated mice, GN application showed reduced cellular filtration followed by epidermal thickness. Thus our assays showed that GN was successful in alleviating the disease caused by Oxa when administered topically.

Keywords: allergen, inflammation, nanodrug, wound

Procedia PDF Downloads 223

Authors: Ashish Jain, Satish Nayak

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Transdermal iontophoretic drug delivery system is viable drug delivery platform technology and has a strong market worldwide. Transdermal drug delivery system is particularly desirable for therapeutic agents that need prolonged administration at controlled plasma level. This makes appropriateness to antihypertensive and anti-diabetic agents for their transdermal development. Controlled zero order absorption, easily termination of drug delivery and easy to administration also support for popularity of transdermal delivery. In this current research iontophoretic delivery of various anti diabetic agents like glipizide, glibenclamide and glimepiride were carried out. The experiments were carried out at different drug concentrations and different current densities using cathodal iontophoresis. Diffusion cell for iontophoretic permeation study was modified according to Glikfield Design. Pig skin was used for in vitro permeation study and for the in-vivo study New Zealand rabbits were used. At all concentration level iontophoresis showed enhanced permeation rate compared to passive controls. Iontophoretic transports of selected drugs were found to be increased with the current densities. Results showed that target permeation rate for selected drugs could be achieved with the aid of iontophoresis by increasing the area in an appreciable range.

Keywords: transdermal, iontophoresis, pig skin, rabbits, glipizide, glibeclamide

Procedia PDF Downloads 362

Authors: Atitallah Sofien, Bouyahia Olfa, Krifi farah, Missaoui Nada, Ben Rabeh Rania, Yahyaoui Salem, Mazigh Sonia, Boukthir Samir

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Introduction: Subcutaneous fat necrosis of the newborn (SCFN) is a rare acute hypodermatitis characterized by skin lesions in the form of infiltrated, hard plaques and subcutaneous nodules, with a purplish-red color, occurring between the first and sixth week of life. SCFN is generally a benign condition that spontaneously regresses without sequelae, but it can be complicated by severe hypercalcemia. Methodology: This is a retrospective case report of neonatal subcutaneous fat necrosis complicated with severe hypercalcemia and nephrocalcinosis. Results: This is a case of a female newborn with a family history of a hypothyroid mother on Levothyrox, born to non-consanguineous parents and from a well-monitored pregnancy. The newborn was delivered by cesarean section at 39 weeks gestation due to severe preeclampsia. She was admitted to the Neonatal Intensive Care Unit at 1 hour of life for the management of grade 1 perinatal asphyxia and immediate neonatal respiratory distress related to transient respiratory distress. Hospitalization was complicated by a healthcare-associated infection, requiring intravenous antibiotics for ten days, with a good clinical and biological response. On the 20th day of life, she developed skin lesions in the form of indurated purplish-red nodules on the back and on both arms. A SCFN was suspected. A calcium level test was conducted, which returned a result of 3 mmol/L. The rest of the phosphocalcic assessment was normal, with early signs of nephrocalcinosis observed on renal ultrasound. The diagnosis of SCFN complicated by nephrocalcinosis associated with severe hypercalcemia was made, and the condition improved with intravenous hydration and corticosteroid therapy. Conclusion: SCFN is a rare and generally benign hypodermatitis in newborns with an etiology that is still poorly understood. Despite its benign nature, SCFN can be complicated by hypercalcemia, which can sometimes be life-threatening. Therefore, it is important to conduct a thorough skin examination of newborns, especially those with risk factors, to detect and correct any potential hypercalcemia.

Keywords: subcutaneous fat necrosis, newborn, hypercalcemia, nephrocalcinosis

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Authors: Ahmad Hashim, Zarizi Ab Rahman

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Measurement of body composition via a field method has the most popular instruments which are used to estimate the percentage of body fat. Among the instruments used are the Body Mass Index, Bio Impedance Analysis and Skinfold Test. All three of these instruments do not involve high costs, do not require high technical skills, are mobile, save time, and are suitable for use in large populations. Because all three instruments can estimate the percentage of body fat, but it is important to identify the most appropriate instruments and have high reliability. Hence, this study was conducted to determine the reliability and convergent validity of the instruments. A total of 40 students, males and females aged between 13 and 14 years participated in this study. The study found that the test retest and Pearson correlation coefficient of reliability for the three instruments is very high, r = .99. While the inter class reliability also are at high level with r = .99 for Body Mass Index and Bio Impedance Analysis, r = .96 for Skin fold test. Intra class reliability coefficient for these three instruments is too high for Body Mass Index r = .99, Bio Impedance Analysis r = .97, and Skin fold Test r = .90. However, Standard Error of Measurement value for all three instruments indicates the Body Mass Index is the most appropriate instrument with a mean value of .000672 compared with other instruments. The findings show that the Body Mass Index is an instrument which is the most accurate and reliable in estimating body fat percentage for the population studied.

Keywords: reliability, validity, body mass index, bio impedance analysis and skinfold test

Procedia PDF Downloads 313

Authors: Bashiru Abdullahi, Isah Bala Yabo, Ibrahim Yakubu Seini

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In this paper, the steady/transient MHD heat transfer within radiative porous channel due to convective boundary conditions is considered. The solution of the steady-state and that of the transient version were conveyed by Perturbation and Finite difference methods respectively. The heat transfer mechanism of the present work ascertains the influence of Biot number〖(B〗_i1), magnetizing parameter (M), radiation parameter(R), temperature difference, suction/injection(S) Grashof number (Gr) and time (t) on velocity (u), temperature(θ), skin friction(τ), and Nusselt number (Nu). The results established were discussed with the help of a line graph. It was found that the velocity, temperature, and skin friction decay with increasing suction/injection and magnetizing parameters while the Nusselt number upsurges with suction/injection at y = 0 and falls at y =1. The steady-state solution was in perfect agreement with the transient version for a significant value of time t. It is interesting to report that the Biot number has a cogent influence consequently, as its values upsurge the result of the present work slant the extended literature.

Keywords: heat transfer, thermal radiation, porous channel, MHD, transient, convective boundary condition

Procedia PDF Downloads 99

Authors: Alexsandro Bayestorff da Cunha, Dpebora Caline de Mello, Camila Alves Corrêa

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In the production of fiberboards, an adhesive based on urea-formaldehyde resin is used, which has the advantages of low cost, homogeneity of distribution, solubility in water, high reactivity in an acid medium, and high adhesion to wood. On the other hand, as a disadvantage, there is low resistance to humidity and the release of formaldehyde. The objective of the study was to determine the viability of adding industrial boiler ash to the urea formaldehyde-based adhesive for the production of medium-density fiberboard. The raw material used was composed of Pinus spp fibers, urea-formaldehyde resin, paraffin emulsion, ammonium sulfate, and boiler ash. The experimental plan, consisting of 8 treatments, was completely randomized with a factorial arrangement, with 0%, 1%, 3%, and 5% ash added to the adhesive, with and without the application of a catalyst. In each treatment, 4 panels were produced with density of 750 kg.m⁻³, dimensions of 40 x 40 x 1,5 cm, 12% urea formaldehyde resin, 1% paraffin emulsion and hot pressing at a temperature of 180ºC, the pressure of 40 kgf/cm⁻² for a time of 10 minutes. The different compositions of the adhesive were characterized in terms of viscosity, pH, gel time and solids, and the panels by physical and mechanical properties, in addition to evaluation using the IMAL DPX300 X-ray densitometer and formaldehyde emission by the perforator method. The results showed a significant reduction of all adhesive properties with the use of the catalyst, regardless of the treatment; while the percentage increase of ashes provided an increase in the average values of viscosity, gel time, and solids and a reduction in pH for the panels with a catalyst; for panels without catalyst, the behavior was the opposite, with the exception of solids. For the physical properties, the results of the variables of density, compaction ratio, and thickness were equivalent and in accordance with the standard, while the moisture content was significantly reduced with the use of the catalyst but without the influence of the percentage of ash. The density profile for all treatments was characteristic of medium-density fiberboard, with more compacted and dense surfaces when compared to the central layer. For thickness, the swelling was not influenced by the catalyst and the use of ash, presenting average values within the normalized parameters. For mechanical properties, the influence of ashes on the adhesive was negatively observed in the modulus of rupture from 1% and in the traction test from 3%; however, only this last property, in the percentages of 3% and 5%, were below the minimum limit of the norm. The use of catalyst and ashes with percentages of 3% and 5% reduced the formaldehyde emission of the panels; however, only the panels that used adhesive with catalyst presented emissions below 8mg of formaldehyde / 100g of the panel. In this way, it can be said that boiler ash can be added to the adhesive with a catalyst without impairing the technological properties by up to 1%.

Keywords: reconstituted wood panels, formaldehyde emission, technological properties of panels, perforator

Procedia PDF Downloads 48