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Objective: Conventional approaches for disinfection, including spraying and immersion, resulted in only surface disinfection of impressions. As a result, self-disinfecting impression materials incorporated with antimicrobial compounds require more extensive studies. The incorporation of a disinfectant into irreversible hydrocolloid impression materials could eliminate the need for the disinfection step by conventional approaches, including spraying and immersion which only result in surface disinfection of impressions. The study was aimed to investigate the effect of incorporation of hypochlorous acid in irreversible hydrocolloid materials on antimicrobial efficiency, detail reproduction, and dimensional stability. Materials and Methods: Hypochlorous acid (HOCl) was used in two concentrations, 100 ppm and 200 ppm, and mixed with alginate powder to compare with the control group (distilled water mixed with alginate). Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosawere chosen for assessing the antimicrobial activity with the disk diffusion test. In addition, the dimensional stability and reproduction of details were tested. Results: The results revealed that both HOCl concentrations of 100 ppm and 200 ppm imposed significant antimicrobial activity against all three tested microorganisms. There was no significant difference regarding reproduction of details, but the addition of the antimicrobial had a significant adverse effect on the alginate’s dimensional stability. Conclusion: It may be concluded that the incorporation of HOCL into irreversible hydrocolloid impression material resulted in an impression with antimicrobial activity. In addition, there was no effect on the impression materials ability to reproduce surface details, but the antimicrobial addition may affect its dimensional stability.

BACKGROUND: and Objectives: Hypocalcemia is a commonly reported complication after thyroid surgery. Many possible risk factors have been identified. The purpose of this study is to analyze various risk factors possibly associated with development of postoperative hypocalcemia after thyroid surgery by dividing the sample population into postoperative hypocalcemia and normal calcium groups. DESIGN: Retrospective SETTING: Multiple centers in the Makkah region of Saudi Arabia PATIENTS AND METHODS: Risk factors for postoperative hypocalcemia that were obtained for analysis include patient factors, perioperative blood parameters factors, disease-related factors, and surgical factors. Postoperative hypocalcemia was defined as a reduction of the total calcium level to

Ceria and ceria-based catalysts are very important in redox and acid-base catalysis. Nanoceria have also been found to be important in biomedical applications. To design efficient materials, it is necessary to thoroughly understand the surface chemistry of ceria, and one of the techniques that provides such information about the surface is the vibrational spectroscopy of probe molecules. Although the most commonly used probe is CO, it has some disadvantages when applied to ceria and ceria-based catalysts. CO can easily reduce the material, forming carbonate-like species, and can be disproportionate, thus modifying the surface. Here, we offer a pioneering study of the adsorption of 15N2 at 100 K, demonstrating that dinitrogen can be more advantageous than CO when studying ceria-based materials. As an inert gas, N2 is not able to oxidize or reduce cerium cations and does not form any surface anionic species able to modify the surface. It is infrared and transparent, and thus there is no need to subtract the gas phase spectrum, something that often increases the noise level. Being a weaker base than CO, N2 has a negligible induction effect. By using stoichiometric nano-shaped ceria samples, we concluded that 15N2 can distinguish between surface Ce4+ sites on different, low index planes; with cations on the {110} facets and on some of the edges, Ce4+−15N2 species with IR bands at 2258–2257 cm−1 are formed. Bridging species, where one of the N atoms from the molecule interacts with two Ce4+ cations, are formed on the {100} facets (2253–2252 cm−1), while the interaction with the {111} facets is very weak and does not lead to the formation of measurable amounts of complexes. All species are formed by electrostatic interaction and disappear during evacuation at 100 K. In addition, N2 provides more accurate information than CO on the acidity of the different OH groups because it does not change the binding mode of the hydroxyls.

The paper deals with the influence of the hydrological regime of the Charyn River, where the Bestyubinsk reservoir was built in 2012, on the state of floodplain geosystems. The research aims to identify and analyze the impact of regulation of the Charyn River flow reservoir on the state of geosystems. Research tasks include (1) calculating and analyzing the hydrological regime of the Charyn River; (2) identifying the sections of the river floodplain most susceptible to the threat of flooding before and after the construction of the reservoir; (3) compiling comprehensive physical and geographical characteristics of the floodplain geosystems of the Taskarasu Valley subject to frequent flooding. In the analysis of the hydrological regime of the river, we used difference and total integral curves to identify the cycles of fluctuations in the annual runoff. The river runoff was estimated by the change in the parameter of the mean annual runoff for 2004–2018. As a result of the interpretation of satellite images, using the Automated Water Extraction Index integrated with ArcGIS, the most frequently flooded area of the river floodplain for this period was identified. The time and area of flooding were determined. Based on the data obtained, the flooded areas were compared for 2004–2018. The advantages of visual observation using satellite images are the ability to clearly and intelligibly visualize the flooded area and systematically, as quickly as possible, reach the required site coordinates using decoded digital data, which is necessary when studying the functioning of geosystems. To describe the state of the floodplain geosystems most susceptible to flooding, we used the data for many years of field landscape studies. Thus, comprehensive physical and geographical characteristics of the Taskarasu Valley were given.

Dental clinicians and professionals need an affordable, nontoxic, and effective disinfectant against infectious microorganisms when dealing with the contaminated dental impressions. This study evaluated the efficiency of hypochlorous acid (HOCl) as an antimicrobial disinfectant by spraying technique for the alginate impression materials, compared with sodium hypochlorite, and its effect on dimensional stability and reproduction of details. HOCl with a concentration of 200 ppm for 5 and 10 min was compared with the control group (no treatment) as a negative control and with sodium hypochlorite (% 0.5) as a positive control. Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa were selected to assess the antimicrobial activity with the colony forming unit test in addition to the dimensional stability and reproduction of details tests. The results revealed that HOCl had significant antimicrobial activity against all tested microorganisms and experimental time. Interestingly, HOCl showed no impact on the dimensional stability of alginate impression material. HOCl could be an effective antimicrobial agent for alginate impression material without interfering with their surface details and dimensional stability.

In this paper, we investigate the effects of in-phase/quadrature-phase imbalance (IQI) on the performance of different modulation schemes under multipath fading channels. In particular, a comprehensive framework for the analysis of coherent and noncoherent modulation with IQI is proposed. Specifically, new moment generating function (MGF) expressions for both point-to-point and multiple antenna systems are derived for the cases of transmitter IQI, receiver IQI, and joint transmitter/receiver IQI. Based on the derived MGFs, new analytical expressions for the corresponding symbol error rate (SER) are derived and are subsequently used to provide deep insights into the effects of IQI on the system performance. It is shown that, while in some cases the SER performance degradation due to IQI is marginal, in other cases, this impairment is more pronounced. Accordingly, IQI compensation is of paramount importance as it can guarantee a reliable communication link. This is particularly important in demanding communication technologies where reduction of latency and complexity are essential.

It is known that self-compacted concrete SCC is used to serve the construction of concrete structures with complicated shapes having congested reinforcements. Sustainable SCC is produced now by recycled concrete aggregates RCA from construction wastes. To improve the strength of this concrete, with a further eye on sustainability, recycled steel fibers RSF is utilized as reinforcing to the SCC. In this work, 12 SCC mixes were prepared with different mixing proportions. Cement is replaced with 5% silica fume. RCA replacement percentages were 25%, 50%, and 100% RCA. RSF was used with 0.50%, 0.75% by volume of concrete. The slump flow, J-Ring, and V-Funnel tests are performed to estimate the rheological behavior of all concrete mixtures. Results indicate that RCA/RSF SCC passed the slump flow, J-Ring tests, and overpassed V-Funnel test requirements satisfactorily.

In this work, we studied the tourist and recreational resources - relict, unique landscapes of the specially protected natural area of the Sharyn. The work is the result of many years of field research on landscapes and summer field practice in 2019 in the Sharyn River basin, the study and systematization of published scientific materials. 4 key sections were laid along 2 routes. On this basis, foci of landscape diversity were identified: relic tracts of Sarytugai with Sogdian ash (Fraxinus sogdiana Bunge), tracts Kurtogay, Moyyntugay and Temirlik with relict morphological sculptures. A digital thematic map was created on ArtGIS 10.1. The “passport” of the existing tourist routes and the “passport” of the recreational load of the protected areas Sharyn have been completed. To remove the anthropogenic load on the Sharyn Canyon, it was proposed to develop two more routes: "Small Canyon" and "Temirlik tract." The scientific base of the tourist and recreational potential has been created and the feasibility of further development of international tourism has been substantiated.

Fine aggregates used for concrete works in Sulaymaniyah city frequently fail to meet the standard requirements for gradation and fineness modulus in cement concrete. This paper aims to critically evaluate gradation, fineness modulus, and clay contents of various natural sands produced and used for concrete work in the region. Sixteen field sand samples were collected from various sites in Darbandikhan (5 samples), Qalat Dizah (5 samples), Koysinjaq (5 samples), and Piramagroon (1 sample) confirming to ASTM D75. The field samples were parted into test specimens based on ASTM C702. Then, sieve analysis was carried out on the oven-dry test specimens in compliance with ASTM C136. The test results of fine aggregates were compared with American, British, and Iraqi specification standards using ASTM C33, BS 882, and IQS No. 45. It was revealed that only three sands satisfy the ASTM gradation limits while others do not comply and are on the coarser side. Also, eight samples meet the requirements recommended by BS 882, whereas five samples meet limits by IQS No. 45. It was found that only three sands have the fineness modulus within the ranges recommended by ACI 211.1 and ACI 211.4, while the others have high values. Furthermore, it was found that all sands include an allowable amount of finer particles passing sieve size 0.075 mm. In order to improve particle size distributions, it is recommended to use the blending method to obtain a suitable fine aggregate from two or more failed sands.

Background: An injury to both the primary and permanent teeth and the supporting structures is one of the most common dental problems seen in children. Splinting is usually difficult or impossible to perform in the primary dentition (due to diminutive room size and lack of patient cooperation). Healing must, therefore, occur despite mobility at the fracture line, usually resulting in interposition of connective tissue. In some instances, infection will occur in the coronal pulp. The present study reported a case of trauma to the anterior primary teeth and alveolar bone in a four year old child. The trauma has caused fracture to the crowns and roots of the primary anterior teeth. The following case was managed in a procedure that may provide primary teeth subjected to trauma a better chance than extraction with a better prognosis. Case presentation: a 4 and a half year old child was subjected to trauma in anterior segment of maxilla. Suturing of the torn soft tissue was the first step followed by pulpotomy for the left primary lateral incisor. Fixation of the right primary central and lateral incisors was done by acid etch wire fixation. Both clinical and radiographic follow up was carried out for 6.4 years. Results: healing of the soft tissue was observed after one week and completed after two months. Fixation of the teeth continued for ten months. The fracture lines in the roots remained in position. Clinically there was no sign of any pulpal inflammation or necrosis. Radiographically, no signs of infection to the surrounding tissues could be seen, no resorption in the alveolar bone, external or internal resorption of the root did not happen also. After ten months fixation ended and the wire was removed. At that time there was normal resorption of the roots of the primary incisors in relation with the normal development of the permanent incisors. After 3 years both permanent central incisors erupted in their normal position. After 6.4 years all four permanent incisors erupted into occlusion in their normal position. Conclusion: primary teeth with root fractures and severely mobile coronal fragments can be treated by a conservative approach. The severity of the sequels is directly related to the degree of permanent tooth formation (child’s age), type of dental trauma and extent of the impact.

A model was presented in a previous study which provided a rational approach to deflection control of reinforced concrete two way slabs considering uncertainties in structural behavior and deflection limits was investigated thoroughly in this work. A simulation model taking into account the uncertainties in materials and loads along with sensitivity analysis of results was developed. Results of simulation represented in the form of probability density function (PDF) and cumulative density function (CDF), optimum thickness and results of sensitivity analysis of reinforced concrete two-way slab systems were presented. In this study, uncertainties in time effects (Creep and shrinkage) are taken into account by using Monte Carlo simulation and are based on proposed variable parameters taken from major references. In general, the proposed procedure results in smaller thicknesses for two-way slab-beam system than ACI 318-14 recommendations for longer spans and larger thicknesses for shorter spans.

Sustainability is a vital and effective contribution to control the use of natural resources in a scientific and accurate manner without wasting work and preserving these resources to meet the current and future needs of societies. The goal of achieving sustainability in construction projects requires procedures that start from design through the use of recyclable materials or reuse. To ensure this, the standards must be defined and implemented in a precise and practical manner. Sustainability criteria for construction projects are organized in sets of questions to be answered by the construction projects officials. These questions take focus on the main building construction steps. The checklist considers weighting the questions according to their level of effect on the sustainability measures. In the current work, 22 construction projects were evaluated in the province of Erbil / Kurdistan region of Iraq through the inclusion of a set of sustainability criteria in the form of questions addressed to the engineers and project managers. The results were analyzed to determine the implementation approaches of the sustainability criteria. Economic, social and environmental factors were included and construction steps were weighed in the questions of the checklist according to these factors. The results confirm the effectiveness of the proposed checklist for estimating a sustainability score for construction projects. The results show high variations in applying sustainability measures in the various construction steps in all of the construction projects. The reasons are due to the absence or weakness of binding laws and the lack of adoption of comprehensive designs based on the pillars of sustainability.

In the current work, 22 construction projects were evaluated in the province of Erbil / Kurdistan region of Iraq through the inclusion of a set of sustainability criteria in the form of questions addressed to the engineers and project managers. The results were analyzed to determine the implementation approaches of the sustainability criteria. Economic, social and environmental factors were included and construction steps were weighed in the questions of the checklist, developed in a companion paper, according to these factors. The results confirm the effectiveness of the proposed checklist for estimating a sustainability score for construction projects. In average, the score of approximately 54% of applying the sustainability measures was obtained. The results show high variations in applying sustainability measures in the various construction steps in all of the construction projects. The reasons are due to the absence or weakness of binding laws, absence of sustainability requirements as a topic in civil engineering curricula, and the lack of adoption of comprehensive designs based on the pillars of sustainability.

الملخص: أهداف البحث: للحصول على تصورات الأطباء عن خبراتهم ووعيهم حول الأحكام المؤسسية التي يمكن أن تعزز مشاركة المريض في المملكة العربية السعودية. طرق البحث: في إبريل٢٠١٧، تم عمل استطلاع عبر الإنترنت عن طريق توزيع استبانة عبر نموذج مستند جوجل للأطباء في المملكة العربية السعودية. يحتوي المستند أسئلة حول خبرة ووعي الأطباء للأحكام المؤسسية من الموارد والدعم. النتائج: استجاب للاستطلاع ٣٢٥ طبيبا. وأوضحت النتائج أن ١٨.٥٪ منهم يرون أن مؤسساتهم تسمح بجدولة المواعيد عن طريق الإنترنت، و٨.٩٪ تسمح بالتواصل بين المرضى والأطباء عبر البريد الإلكتروني، و٢٤٪ تسمح لوصول المرضى للسجلات الصحية ونتائج التحاليل عبر الإنترنت، و٥٥.٧٪ تسمح بتوفير البرامج التعليمية متعددة الوسائط، و٧٤.٨٪ تسمح بصنع القرار-المشترك بين الأطباء والمرضى. كما ذكر ٣٤.٥٪ فقط من المستجيبين أن مؤسساتهم تقوم بتوفير زيارات منزلية للمرضى ذوي الخطورة العالية. يرى ستة من ١٠ مستجيبين أن هذه الأحكام سيكون لها تأثير إيجابي ونتيجة لهم وأيضا لمرضاهم. الاستنتاجات: يعي الأطباء ويقيمون الأحكام التي تعزز مشاركة المريض. ولكن العديد من المؤسسات لا تدعم وتمارس هذه الأحكام التي تعزز مشاركة المريض. الأطباء الذكور ذوي الخبرة الأطول من الممارسة وأولئك الذين يشغلون مناصب إدارية عليا هم أكثر من يقدم الدعم، ويقدر أهمية تعزيز مشاركة المريض في ممارستهم. Abstract: Objectives: To survey physicians' perceptions of their experience and awareness of institutional provisions that can potentially foster patient engagement (PE) in KSA. Methods: In April 2017, an online survey was distributed to clinicians in KSA using Google Forms. The instrument contained questions about the physicians' awareness and experience of their institutions' provision of resources and support. Results: Three hundred and twenty-five clinicians responded to the survey The results showed that 18.5% claimed that their institutions allowed online scheduling of appointments; 8.9% reported the institutions permitted contact between patients and physicians through email; 24.0% reported they provided patients with online access to health records and test results; 55.7% claimed they provided educational multimedia programming; and 74.8% confirmed they encouraged joint decision-making between physicians and patients. Only 34.5% of respondents claimed their institutions provided home visits for high-risk patients. Six of 10 respondents thought that such provisions would have positive outcomes for them and for their patients. Conclusions: Clinicians are aware of and value provisions that foster PE. However, several institutions in KSA do not support or have provisions in place to foster PE. Male clinicians with longer durations of practice and those with higher administrative positions are more likely to value the importance of PE and support and use it in their practice. الكلمات المفتاحية: إشراك, المؤسسية, المريض, الأحكام, الدعم, Keywords: Foster, Institutional provision, Patient engagement

The model presented in this study provides a rational approach to deflection control of reinforced concrete two way slabs considering uncertainties in structural behavior and deflection limits and recognizes that the problem is subject to wide and unavoidable variability. Concepts of Monte Carlo simulation and utility theory are presented. A simulation model taking into account the uncertainties in materials and loads along with sensitivity analysis of results are presented. Results of simulation represented in the form of probability density function (PDF) and cumulative density function (CDF), optimum thickness and results of sensitivity analysis of reinforced concrete two-way slab systems are presented. This study explores the application of utility theory to the problem because serviceability failure can occur in structures with adequate safety against collapse, in which the question becomes an economic issue. In this study, uncertainties in time effects (Creep and shrinkage) are taken into account by using Monte Carlo simulation and are based on proposed variable parameters taken from major references.

To make concrete a truly green material, viable cement substitutes are available. This experimental investigation is performed to study the effect of using limestone powder (LSP) and styrene butadiene rubber (SBR) latex in the concrete mix. In this work, a concrete with 1:1.8:3 cementitious material:sand:gravel and water/cement ratio w/c of 0.5 is produced. First, LSP is used with 0, 5, 10, 15, and 20% replacements by weight of cements. The fineness of the LSP is measured using sieve No. 200 and showed about 30% pass. Second, and to improve the matrix of concrete due to the dilution effect, four ratios of SBR latex (0, 5, 10, and 15%) are added by weight of cements to the mix for each LSP ratio. Compressive strength at ages of 3, 7, 14, 28, and 90 days is tested for the concrete specimens mixed with LSP only to examine its effect on concrete strength’s development with time, whereas strengths are recorded at the age of 28 days for the other concretes. Three prisms were cast for each ratio and tested at 28 days. The results show general improvements in terms of compressive and flexural strengths.

Multiple-input-multiple-output (MIMO) techniques have recently demonstrated significant potentials in visible light communications (VLC), as they can overcome the modulation bandwidth limitation and provide substantial improvement in terms of spectral efficiency and link reliability. However, MIMO systems typically suffer from inter-channel interference, which causes severe degradation to the system performance. In this paper, we propose a novel optical adaptive precoding (OAP) scheme for the downlink of MIMO VLC systems, which exploits the knowledge of transmitted symbols to enhance the effective signal-to-interference-plus-noise ratio. Furthermore, we derive bit-error-rate expressions for the proposed OAP scheme under perfect and outdated channel state information (CSI). Our results demonstrate that the proposed scheme is more robust to both CSI error and channel correlation, compared to conventional channel inversion precoding. These results are expected to provide useful insights in the effective design and efficient operation of VLC networks.

Non-orthogonal multiple access (NOMA) has been recently proposed as a viable technology that can potentially improve the spectral efficiency of fifth generation wireless networks and beyond. However, in practical communication scenarios, transceiver architectures inevitably suffer from radiofrequency (RF) front-end related impairments that can lead to degradation of the overall system performance with in-phase/quadrature-phase imbalance (IQI) constituting a major impairment in direct-conversion transceivers. In this paper, we quantify the effects of IQI on the performance of NOMA-based single-carrier (SC) and multi-carrier (MC) systems under multipath fading conditions. This is realized by first deriving analytic expressions for the signal-to-interference-plus-noise ratio and the outage probability of both SC and MC NOMA systems subject to IQI at the transmitter and/or receiver (RX) side. Furthermore, we derive asymptotic diversity orders for all considered impairment scenarios. Capitalizing on these results, we demonstrate that the effects of IQI differ considerably among NOMA users and depend on the underlying systems' parameters. For example, for a target data rate and power allocation ratio satisfying a given condition, IQI does not affect the asymptotic diversity of SC NOMA systems, whereas the asymptotic diversity of MC NOMA systems, suffering from RX IQI, is always zero. Moreover, it is shown that for both SC and MC NOMA systems, the first sorted user appears more robust to IQI, which indicates that higher order users are more sensitive to the considered impairment.

This study intends to analyze and design existing RC frames, of different concrete compressive strengths when extended by adding more floors to the existing buildings. It may be decided whether a strengthening scheme is feasible or not.In this work, analyses are made of 3 buildings of 14-stories with different compressive strengths in the first 6-floor columns for each building, extended to 16-stories frame by adding 2 stories of Normal weight concrete (NWC) or Steel.A case study is selected which is an existing RC buildings, and the owner requested 2 additional floors. It is assumed that the foundation system is capable of carrying the additional floors. First the capacity of the superstructures must be known, by using data obtained from the previous designs of the existing buildings.After extending the building by NWC or Steel, by using STAAD-pro, it has been shown that a considerable portion of the total number of columns in the superstructure of the existing building couldn’t carry the new loads due to the additional 2 floors, so in order to add two additional floors, strengthening scheme must be planned for the columns which require additional capacity.

A total of fourteen beams, 100×150 mm in cross-section were tested in the laboratory over an effective span of 2000 mm. Two of them were used as reference beams. Twelve fiber reinforced concrete beams were provided with externally bonded CFRP laminates at the soffit of the beam. The variables considered included number of CFRP layers, yield strength of steel reinforcement (fy) and steel reinforcement ratio (). All the beams were tested until failure. The test results showed that the ultimate load carrying capacity increased by 56% as average by increasing of the ratio of steel reinforcement from (0.0127 to 0.0324). The deflection ductility index DDI values averaged (1.80) and (1.75) for one-layer strengthened beams and two-layer ones, respectively. The corresponding energy ductility index EDI values averaged (1.75) and (1.73), respectively. The DDI and EDI for the control beams were 4.61 and 6.24, respectively. With the exception of the control beams, all of the beams exhibited poor ductility. Failures in all strengthened beams were accompanied by the release of large amounts of energy (known as elastic energy) relative to inelastic energy. Therefore, a reasonable factor of safety should be used in the design of FRP strengthened reinforced concrete members.

* Backgrounds The retention of the maxillary complete denture may be influenced by adequate recording in the patient’s mouth, marking, and carving of the post-dam on the maxillary cast. Failure to do so may lead to loss of retention. Successful denture construction with patient’s comfort could be achieved by effective methods of recording, marking, and carving of the post-dam. The aim of the study was to assess Iraqi dentists in their knowledge and application of the post-dam in maxillary complete dentures. Methods Questionnaires were distributed randomly through online Google Forms and 118 Iraqi dentists with different academic degree participated in the study. A multinomial logistic regression model was also used to assess the nominal outcome variables. Results A High percentage of 90.7% of Iraqi dentists with different academic degree stated that they had the knowledge about the vibrating lines and their location and 84.7% stated that they mark the post-dam on the master cast, while 15.3% stated that the dental technician marks it. More the half (52.5%) of the participants carved the post-dam, while 47.5% of the participants stated that the dental technician did it. For participants not marking the post-dam, 30.5% of the participants stated they depend on the dental technician in marking and/or carve the post-dam, while the fear of denture failure and loss of retention was observed in 25.4% of the participants, followed by 24.6% of participants forgetting to carve, 10.2% of participants had no information about carving, and 9.3% participants found it was difficult to carve. Conclusions Within the limitations of the study, most Iraqi dentists with different academic degree stated that they had the knowledge on the location of vibrating lines. However, recording and carving the post-dam was influenced by the dentist’s personal preference and their dependency on the dental technician.

The current ACI code and many other codes permit the moment magnification method for design of slender reinforced concrete (RC) columns. Manually, the design/analysis procedure is tedious, so that the codes state a pre-prediction if the column is slender or not. In other words, before starting design codes provide slenderness limits to be considered to decide whether a column is slender or not. This work will concentrate on the slender RC column provisions of the latest ACI Code. Using this method some columns are found to be short. In the proposed method of this work, it is found that some of these short columns are found to be long , thus needing moment magnification. Since column analysis/design represents dealing with one of the most critical parts of RC buildings, this proposed magnification is presented in this work.

Background: Dental casts come into direct contact with impression materials and other items that are contaminated by saliva and blood from a patient's mouth, leaving the casts susceptible to cross-contamination. The disinfectant solutions of the impression materials cause various adverse reactions. Therefore, disinfection of dental casts may be effective in preventing cross infection. This study was carried out to evaluate the surface hardness, dimensional accuracy, reproduction of details and surface porosity of type III, type IV and type IV extra hard dental stone after immersion in and spray by using SOLO and Sodium hypochlorite disinfectant solutions. Materials and methods: 240 Stone samples were prepared in rubber rings, A total of 60 test block were prepared for each test (surface hardness, dimensional accuracy, reproduction of details and surface porosity).the samples were divided into three groups (20 for each type of stone) type (III, IV, IV extra hard); SOLO and Sodium hypochlorite disinfectant by 2 methods (immersion and spray) were used in each test. Results: the results of dimensional accuracy, reproduction of details, surface hardness and surface porosity revealed no significant difference for all types of tested stone samples after immersion or spraying in SOLO and NaOCl except the surface hardness of type IV extra hard showed significant difference after spray with SOLO and the surface porosity of type IV extra hard showed significant difference after immersed in both SOLO and NaOCl solutions. Conclusions: Based on the results of this study immersion in and spray by using SOLO and NaOCl disinfectant solutions produced no adverse effect on dimensional accuracy, reproduction of details, surface hardness and surface porosity for type III, type IV dental stone and for type IV extra hard dental stone except for the surface hardness for type IV extra hard when sprayed with SOLO and the surface porosity when type IV extra hard stone immersed in the SOLO and NaOCl solutions.

This work aims at studying the post–heating behavior of normal strength concrete (NSC), high strength concrete (HSC), and lightweight concrete (LWC) slabs and assessing the residual flexural strength of two-way slab specimens. Eleven reduced scales reinforced concrete slab specimens divided into three main groups representing the NSC, HSC, and LWC types of corresponding cube compressive strengths of 50, 94, and 37 N/mm2 respectively, are prepared in the laboratory. Residual flexural strength, load–deflection curves, crack patterns, failure characteristics and details, and effects of temperature level exposure are all recorded, investigated, and discussed. Effects of concrete type when slabs are exposed to different temperature levels are also discussed. Results indicate a reduction of strength with exposure to high temperatures. Residual flexural strength percentages at maximum temperature exposure (700˚C) are 44.5%, 38.7%, and 45.5% for NSC, HSC, and LWC slabs, respectively.

This research include the study of Structural Behaviour of Polymer Modified Reinforced Concrete Beams with Styrene Butadiene Rubber (SBR) polymer. Two series of concrete mixtures were used; the first was with moderate compressive strength (level I) and the other with compressive strength higher than the former (level II). Two reference mixes were made also for comparative purposes.This study includes compressive and flexural tests for concrete which was used in this research. The results prove that, polymer modified concrete has compressive and flexural strengths more than reference mixes. Eight beams are moulded of (95X200X1600mm) dimension with different steel reinforcement ratio (ρ). Load-deflection relationships of beams made of polymer modified concretes and references concretes were established. The moment at mid-span with deflection and moment-curvature relationships were established too.The effects of steel reinforcement ratio (ρ) and (ρlρmax) on the displacement ductility of reinforced concrete beams were concluded.The PMC beams have a stiffer response in terms of structural behaviour, more ductility and lower cracking deflection than those made by reference concretes and that refer to good role of styrene Butadiene Rubber (SBR) polymer on the properties and behaviour of reinforced concrete beams.

This paper presents investigation on the strength and deformation characteristics of reinforced normal and high strength concrete rectangular beams failed in shear and repaired by epoxy injection.Eight simply supported reinforced concrete beams without shear reinforcement are tested, four of which are made with normal-strength concrete (NSC) and four with high-strength concrete (HSC). The span of the simply supported beams is 1.28 m with 100 mm wide by 200 mm deep cross section. All are tested under two-point loads.Method of epoxy injection is used to repair cracks in the failed-in-shear beams. Careful repair process is adopted and proved successful.Main conclusions are: successful repair method is used to increase or at least restore shear capacity of beams; the increase is observed higher in normal-strength beams; repaired diagonal shear cracks do not reopen (generally) after retesting, instead, new nearby diagonal shear cracks are developed and the repaired beams show a lower stiffness and greater ductility than original beams.

This study presents experimental and theoretical investigation of shear behavior of hybrid reinforced concrete I-beams cast monolithically, but, the web is made with concrete differing from concretes of compression and tension flanges.A rational way has been used by replacing (or strengthening) a certain part(s) or layer(s) of I-shaped reinforced concrete beams by steel fiber reinforced concrete (SFRC) or high strength concrete (HSC). Three beams were tested in this investigation and only the concrete type of the web was varied. Experimental results showed that the ultimate shear strengths are increased (15 or 25%), while the reserve shear strength (after diagonal cracking) is increased (6 or 10%) for the tested beams containing SFRC or HSC in the web respectively. Crack arrest mechanism of steel fibers, and high compressive strength of concrete improved the tensile response, limited crack propagation, improved reserve strength and altered the failure mode. So, more safety was obtained.ANSYS finite Element models are used to simulate all tested beams.

This paper presents an investigation of the strength and deformation characteristics of reinforced concrete rectangular beams failed in shear and repaired by epoxy injection.Five simply supported reinforced normal-strength concrete (NSC) beams without shear reinforcement are used. The span of the simply supported beams is 1.28 m with 100 mm wide by 200 mm deep cross section. All beams are tested under two-point loads.A method of epoxy injection is used to repair cracks in the failed-in-shear beams. Careful repair process is adopted and proved successful.The Main conclusions are: a successful repair method is used to increase or at least restore the shear capacity of beams; repaired diagonal shear cracks do not reopen after retesting, instead, new nearby diagonal shear cracks are developed and the repaired beams show a lower stiffness and greater ductility than the original beams.

The deflection of a member can be determined more accurately from the values of the mean curvatures of a number of sections using simple geometrical deflection-curvature relations taking into account the effect of tension stiffening. Thus, the "The Proposed Mean Curvature" idealization is derived in this work exclusively for prestressed concrete members taking into consideration the effect of cracking of these members. It shows better agreement with experimental data than the conventional models, which are established essentially for normal strength concrete and do not fit higher-strength concrete. The computer program "PPCD" is developed in this work following the proposed model. Immediate and time dependent deflections of prestressed concrete beams can be computed. Concrete compressive strength, tension-stiffening effect, and time-dependent factors are included in this program. This program has been verified once to typical studied example with varying concrete compressive strengths and furthermore to an experimental data. The results indicate that the accuracy of The Proposed Model in deflection predicting is acceptable for partially prestressed concrete members of any concrete compressive strength.

This literature review emphasizes the impact of aluminum oxide sandblast particles as a surface treatment agent on bond strength of heat-cured and 3D-printed polymethyl methacrylate denture bases and silicone soft liner. Denture soft liner materials play a crucial role in prosthodontics by enhancing comfort and tissue adaptability for denture users, as well as restoring irritated and deformed mucosa. The primary disadvantage of denture soft liner is the separation of the lining material from the denture base, known as debonding. Hence, it is important to improve the cohesion of these parts. [ABSTRACT FROM AUTHOR]

Ceria and ceria-based catalysts are very important in redox and acid-base catalysis. Nanoceria have also been found to be important in biomedical applications. To design efficient materials, it is necessary to thoroughly understand the surface chemistry of ceria, and one of the techniques that provides such information about the surface is the vibrational spectroscopy of probe molecules. Although the most commonly used probe is CO, it has some disadvantages when applied to ceria and ceria-based catalysts. CO can easily reduce the material, forming carbonate-like species, and can be disproportionate, thus modifying the surface. Here, we offer a pioneering study of the adsorption of 15N2 at 100 K, demonstrating that dinitrogen can be more advantageous than CO when studying ceria-based materials. As an inert gas, N2 is not able to oxidize or reduce cerium cations and does not form any surface anionic species able to modify the surface. It is infrared and transparent, and thus there is no need to subtract the gas phase spectrum, something that often increases the noise level. Being a weaker base than CO, N2 has a negligible induction effect. By using stoichiometric nano-shaped ceria samples, we concluded that 15N2 can distinguish between surface Ce4+ sites on different, low index planes; with cations on the {110} facets and on some of the edges, Ce4+−15N2 species with IR bands at 2258–2257 cm−1 are formed. Bridging species, where one of the N atoms from the molecule interacts with two Ce4+ cations, are formed on the {100} facets (2253–2252 cm−1), while the interaction with the {111} facets is very weak and does not lead to the formation of measurable amounts of complexes. All species are formed by electrostatic interaction and disappear during evacuation at 100 K. In addition, N2 provides more accurate information than CO on the acidity of the different OH groups because it does not change the binding mode of the hydroxyls. [ABSTRACT FROM AUTHOR]

The Almaty region, which is rich in natural landscapes, was established again in 2022. In this regard, the importance of regional spatial planning is taking on new forms. Considering the unique landscape potential, this project aims to create a framework for developing tourist and recreational complexes in the Uygur, Kegen, and Raiymbek regions. Creating a landscape diversity database to classify recreational resources; developing a typology for tourist and recreational complexes, considering the landscape's features and the tourism specializations. The research methods used in this study include field observations and landscape descriptions provided by the authors. A classification method has been developed to divide recreational resources into groups and sub-groups, determining their locations. The process of the developed typology is based on examples of specific types of tourist and recreational activities, as well as existing and potential tourist areas in the Almaty region and the Republic of Kazakhstan. The theoretical and methodological basis for the proposed classification and typology is based on the work of various authors and materials from the National Science Foundation of Kazakhstan. Issues of the possibilities of agricultural enterprises to provide tourists with local, natural food products have been analy zed. Based on these factors, recommendations were formulated for further developing promising tourist and recreational complexes in these areas. All authors have read and agreed to the published version of the manuscript. [ABSTRACT FROM AUTHOR]