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A sieve is a device for separating wanted elements from unwanted material or for characterizing the particle size distribution of a sample, typically using a woven screen such as a mesh or net. This project focuses in design, fabrication of the mechanical part of machine and the system of the sieve machine. To achieve this project objective, this sieve machine body structure and mechanical system needs to concern some other criteria such as strength, safety and ergonomic design. Depending on their size the individual particles either pass through the sieve mesh or retained on the sieve surface. There are different machines that are being used for sand sieving processes. In our project the process will takes place automatically. Thus, the time consumed during the whole process is reduced. Keywords: Sieving Machine, Sand Sieving Machine, Sieving Machine Fabrication, Automatic Sieving

Wire arc additive manufacturing (WAAM) is an additive manufacturing process based on the arc welding process in which wire is melted by an electric arc and deposited layer by layer. Due to the cost and rate benefits over powder-based additive manufacturing technologies and other alternative heat sources such as laser and electron beams, the process is currently receiving much attention in the industrial production sector. The gas metal arc welded (GMAW) based WAAM process provides a higher deposition rate than other methods, making it suitable for additive manufacturing. The fabrication of mild steel (G3Si1), austenitic stainless steel (SS304), and a bimetallic sample of both materials were completed successfully using the GMAW based WAAM process. The microstructure characterization of the developed sample was conducted using optical and scanning electron microscopes. The interface reveals two discrete zones of mild steel and SS304 deposits without any weld defects. The hardness profile indicates a drastic increase in hardness near the interface, which is attributed to chromium migration from the SS304. The toughness of the sample was tested based on the Charpy Impact (ASTM D6110) test. The test reveals isotropy in both directions. The tensile strength of samples deposited by the WAAM technique measured slightly higher than the standard values of weld filament. The deep hole drilling (DHD) method was used to measure the residual stresses, and it was determined that the stresses are compressive in the mild steel portion and tensile in austenitic stainless steel portion, and that they vary throughout the thickness due to variation in the cooling rate at the inner and outer surfaces.

Supplemental material, sj-docx-1-pie-10.1177_09544089211037443 for Multi-response modeling for sliding wear behavior of AA5052/TiC composites by stir casting: A comparative analysis using response surface methodology and fuzzy logic system by Priyaranjan Samal, Pandu R Vundavilli, Arabinda Meher and Manas M Mahapatra in Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering

Background: PCSK9 inhibitors are a treatment option for patients with familial hypercholesterolemia not on low-density lipoprotein cholesterol goals despite the use of maximally tolerated high intensity-statins dose. Objective: To evaluate the efficacy of alirocumab and evolocumab in LDL-C reduction and targets attainment in patients with heterozygous familial hypercholesterolemia in clinical practice setting. Methods: SAFEHEART is an open, long-term prospective study of a cohort of subjects with molecular diagnosis of familial hypercholesterolemia. This study analyze subjects >= 20 years of age on stable lipid-lowering therapy, who received PCSK9 inhibitors during the period 2016 to January 2020. Results: 433 patients (mean age 55 years, 53% male, 39% with cardiovascular disease) were included and followed-up for a median of 2.5 years (IQR 1.6-3.0). Median LDL-C level prior to PCSK9 inhibitors was 145 mg/dL (IQR 125-173). The addition of PCSK9 inhibitors (211 alirocumab, 222 evolocumab) reduced LDL-C by 58% (IQR 41-70) p

The article presents the results of treatment of 26 patients with purulent-necrotic com-plications of diabetic foot from 2019 to 2020, who are being treated at the Aktobe Medical Center. All patients were prescribed complex therapy and small foot surgeries were performed. The patients were divided into two groups: the control group, where ointment dressings and stage necrectomies were used ��� 12 patients and the main group ��� 14 patients, vacuum therapy was used. The average duration of one dressing was 4 days. Bandages were applied according to the existing method. A porous polyu-rethane sponge was applied to the wound, followed by sealing with a transparent adhesive film, with a drainage tube connected to a vacuum device. To evaluate the results, we used: changes in glucose lev-els, the dynamics of the microbial landscape and the wound process, treatment outcomes, the time of healing of the defect and the presence of patients in the hospital. Conclusion: the use of vacuum therapy in the treatment of purulent wounds contributed to a no-ticeably rapid cleaning of wounds and, accordingly, a decrease in their area and depth, an acceleration of the process of granulation and epithelization in comparison with traditional methods of treatment. Key words: diabetic foot syndrome, vacuum therapy, complication, local treatment.

The objective of the current study is to investigate the effects of geometric parameters on the fluid flow patterns, diffusion factor, load-split, and off-design performance of the tandem configuration under subsonic, rectilinear, cascade flow. A 2-D computational model using finite volume formulation has been developed and validated against available experimental data. The obtained data is presented in a format involving loss parameter and loading and will help the designer to have sufficient number of combinations within the useful range of application. It is observed that general performance behavior of tandem cascade is similar to a single airfoil data. Load shifting from the front airfoil to the rear airfoil is noted at positive axial overlaps and higher camber ratios. An optimum gap ratio of around 2 is observed for the range of configurations investigated. Contrary to the previous literature, the present study indicates higher loading of the front airfoil for the best overall loading-to-loss ratio of the tandem configuration.

Purpose To identify and validate risk factors that contribute to prolonged length of hospital stay (LOS) in patients undergoing resection for colorectal cancer. Methods This prospective cohort study included 1955 patients admitted to 22 hospitals for primary resection of colorectal cancer. Multivariate analyses were used to identify and validate risk factors, randomizing patients into a derivation and a validation cohort. Multiple correspondence and cluster analysis were performed to identify clinical subtypes based on LOS. Results The strongest independent predictors of prolonged LOS were postoperative reintervention, surgical site infection, open surgery, and distant metastasis. The multiple correspondence and cluster analysis provided three groups of patients in relation to prolonged LOS: patients with the longest LOS included the highest percentage of patients with open surgery, distant metastasis, deep surgical site infections, emergency admissions, additional diagnostic factors, and highly contaminated surgical sites. Patients with prolonged LOS (> 14 days) were more likely to develop adverse outcomes within 30 days after discharge. Conclusions Patients undergoing resection of colorectal cancer cluster into different groups based on LOS of the index admission. Those with prolonged LOS were more likely to develop adverse outcomes within 30 days after discharge. Some of the strongest independent predictors of prolonged LOS, such as surgical infections or open surgery, could be modified to reduce LOS and, in turn, other adverse outcomes.

We introduce a new class of long and thin continuum robots intended for use in space applications. This ‘cable’ robot is a next-generation version of the current state of the art (NASA’s ‘Tendril’). The article describes the key practical limitations of the mechanical design of ‘Tendril’. We introduce the design specifics of our novel concept for a next-generation device with significantly enhanced performance. Equipped with a light and compact motor-encoder actuation mechanism, the new design has improved compliance and possesses a concentric backbone arrangement which is tendon-actuated and spring-loaded. A new forward kinematic model is developed extending the established models for constant-curvature continuum robots, to account for the new design feature of controllable compression (in the hardware). The model is validated by performing experiments with a three-section prototype of the design. The new model is found to be effective as a baseline to predict the performance of such long and thin contin...

An efficient pot and time economic ‘dry-media’ synthesis of pyrimidine core containing scaffolds by application of an indium triflate catalyzed carbon–carbon bond formation procedure through Diels–Alder reaction using microwaves is described. The method is associated with some attractive characteristics such as short reaction time, high yield of products, and recyclability of recovered catalyst from the reaction mixture.

An efficient pot and step economic protocol for synthesis of pyrido[2,3-d]pyrimidine derivatives from a multicomponent aza-Diels–Alder reaction of uracil analogues, aromatic aldehydes and acetophenones in the presence of Na2CO3 in DMF was developed. The key step of the reaction is in situ generation of the reactive dienophile from aldehyde and acetophenone and their subsequent reaction with diene to give the desired product.

An one-pot, solvent-free imino Diels–Alder reaction has been developed under microwave conditions using 1-naphthylamine, aldehydes, and electron-deficient terminal alkynes in the presence of a catalytic amount of In(OTf)3 for construction of benzo[h]quinoline derivatives in short reaction times. The method is clean and operationally simple.

A solvent- and catalyst-free Diels–Alder reaction with 6-(2-morpholinovinyl)-1,3-dimethyluracil, cinnamaldehyde, and an amine has been developed for the construction of iminoquinazoline-2,4-dione derivatives within a short reaction time. The method is clean, simple, and operation friendly.

A mild and efficient protocol for the synthesis of various tetrahydroquinazolinedione and dihydropyrido[2,3-d]pyrimidine-2,4-dione templates from uracil derivatives utilizing a [4+2]-cycloaddition strategy in a one-pot reaction has been developed.

A microwave-promoted solvent- and catalyst-free aza-Diels–Alder reaction is described. 6-[2-(dimethylamino)vinyl]-1,3-dimethyluracil reacts with aldehyde and amine inside a microwave reactor to produce dihydropyrido[4,3-d]pyrimidine derivatives in excellent yield and within a very short time.

A mild and efficient protocol for the synthesis of pyrano[3,2- C]coumarins from 4-hydroxycoumarinthrough a one-pot -reaction in water under phase-transferconditions has been developed.

An efficient pot and time economic ‘dry-media’ synthesis of pyrimidine core containing scaffolds by application of an indium triflate catalyzed carbon–carbon bond formation procedure through Diels–Alder reaction using microwaves is described. The method is associated with some attractive characteristics such as short reaction time, high yield of products, and recyclability of recovered catalyst from the reaction mixture.

The reaction succeeds using aryl aldehydes as the reaction partner, but fails with alkyl aldehydes and phenyl glyoxal derivatives.

In this paper, we present a new forward kinematic model for a novel class of long and thin continuum robots for operation in spatial workspace. Such robots are well suited for navigation through unstructured environments with superior reach using their flexible and thin profile, especially for inspection applications. This cable-like continuum robot design [1] has a concentric backbone arrangement but is spring-loaded and tendon-actuated, has improved compliance with a light and compact motor-encoder actuation mechanism. To account for the spring-loading, a compression factor is introduced on top of the established constant curvature continuum kinematics. The resulting continuum or shape variables are then estimated as a function of the measurable encoder variables. The effectiveness of the model is validated by performing experiments with the robot prototype.

Spiroindenotetrahydropyridine derivatives are synthesized from 1,3-indanedione (I), aromatic aldehydes (II), and ammonium acetate.

In the present work, a numerical elasto-plastic thermo-mechanical model has been developed to predict the weld-induced angular distortion of single-sided and double-sided fillet joints by submerged arc welding (SAW) process. The welding was carried out by using recyclable flux-filled backing strip in single pass. The angular deformations for both the cases have been measured experimentally. It has been found that the maximum magnitude of angular deformation is lower in case of double-sided fillet joint. A detail comparative study of the angular deformation between single- and double-sided fillet joints has been presented in this study. It has been observed that the developed elasto-plastic thermo-mechanical model is well comparable with experimental results.

Dienophiles generated in situ from aldehydes and acetophenones undergo aza-Diels—Alder reaction with uracil derivative (I) followed by oxidative aromatization to give pyridopyrimidines.

In this paper, we present a novel design for constructing multi-section continuum robots with a special focus on thin (less than 1 cm diameter) and relatively longer length (more than 100 cm), along with its new kinematic modeling and performance evaluation. This spring-loaded, tendon-actuated cable-like continuum robot incorporates key features of a concentric tube style design with added local compression to most sections and actively controllable bending along its entire backbone. It also avoids a complicated and large actuator system. Such robotic cables can be well suited for current space and terrestrial applications like exploration, teleoperation, surveillance, maintenance activities, etc., benefiting from these unique structural properties.

CyberPLAYce is our novel, interactive-computational construction kit for elementary school children and their teachers. CyberPLAYce bridges the physical and digital worlds, allowing young students to bring their ideas, stories and class subjects to life through the construction of cyber-physical environments. The CyberPLAYce construction kit is comprised of hand-sized, magnetic modules integrating a variety of electronic components, and rectangular panels, nearly two-feet measured diagonally, that receive the modules and serve as physical building blocks for constructing cyber-physical environments imagined by children. Through play, children become comfortable with the working modules and panels; subsequently, they are provided matching non-electronic module cards allowing them to quickly compose pattern sequences to map ideas, stories and class content. Additionally, students are provided action and story cards to spark their imagination. CyberPLAYce merges play and learning in the physical world while transitioning students from consumers of virtual and digital-centric technologies into technological innovators and cyber-playful storytellers.

Design of continuum robots, i.e. robots with continuous backbones, has been an active area of research in robotics for minimally invasive surgery, search and rescue, object manipulation, etc. Along the same lines, NASA developed “Tendril”, the first long and thin continuum robot of its kind, intended for in-space inspection applications. In this paper, we describe and discuss the key disadvantages of state of the art mechanical design producing undesirable effects during operation. We then provide the specifics of a new, next generation, thin rope-like robot with a modified mechanical design for better performance having key features like controllable bending along its entire length, local compression and potentially smaller actuation package.

In situ generated enimines undergo Diels—Alder reactions with morpholinovinyl- or dimethylaminovinyl substituted uracil derivatives, followed by elimination of the amino group and aromatization to give the title compounds (IV) in good yields.

Uracil derivatives (I) and (IV) are employed as diene components for the reaction with aromatic nitroalkenes.

A facile synthesis of the title compounds is achieved by microwave promoted three-component aza-Diels—Alder reaction of uracil derivative (I), aldehydes, and amines.

A microwave-promoted aza-Diels–Alder reaction between 6-[2-(dimethylamino)vinyl]-1,3-dimethyluracil and aldimines has been developed for the construction of dihydropyrido[4,3-d]pyrimidines. Urea is effectively employed as an environmentally benign source of ammonia in the absence of any catalyst or solvent. The key step in the reaction is in situ generation and trapping of the reactive aldimine formed from urea and aldehyde by the diene system of the uracil. The reaction is clean, and excellent yields are obtained in a matter of a few minutes.

A microwave-promoted aza-Diels–Alder reaction between 6-[2-(dimethylamino)vinyl]-1,3-dimethyluracil and aldimines has been developed for the construction of dihydropyrido[4,3-d]pyrimidines. Urea is effectively employed as an environmentally benign source of ammonia in the absence of any catalyst or solvent. The key step in the reaction is in situ generation and trapping of the reactive aldimine formed from urea and aldehyde by the diene system of the uracil. The reaction is clean, and excellent yields are obtained in a matter of a few minutes.

Optimal management of proximal biliary strictures depends on staging and adequate tissue diagnosis of suspected malignant lesions. Sensitivity of ERCP brush cytology is poor. EUS/EUS-FNA of these lesions is challenging with limited data on its diagnostic accuracy. We report our experience of EUS/ EUS guided FNA of proximal biliary strictures in a tertiary referral centre.All patients who underwent EUS guided FNA of hilar lesions between October 2003 to July 2007 were identified. The final diagnosis was determined by surgical pathology, results of EUS-FNA or follow-up.32 patients underwent 36 procedures for hilar lesions during the study period. EUS detected a mass in 9/14 patients who did not have a mass seen on imaging. The mean followup period was 39.43 months. The cytological specimen was adequate in 26 patients. The final diagnosis was adenocarcinoma (24) and benign (8). The overall accuracy, sensitivity, specificity, positive predictive value and negative predictive value of EUS-FNA were 68%, 52 %, 100%, 100% and 54%, respectively. If only adequate aspirates were included in the analysis, the values were 74%, 60%, 100%, 100% and 55% respectively.EUS guided FNA is a useful modality in the diagnosis and management of hilar lesions.

The title compounds are prepared in high yields and short reaction times via phase-transfer-catalyzed reactions of 4-hydroxycoumarin (I).

The vectorial fundamental transformation for the Darboux equations is reduced to the symmetric case. This is combined with the orthogonal reduction of Lame type to obtain those vectorial Ribaucour transformations which preserve the Egoroff reduction. We also show that a permutability property holds for all these transformations. Finally, as an example, we apply these transformations to the Cartesian background., Comment: 15 pages LaTeX2e with AMSLaTeX and Babel packages

The submitted article describes the effects of a thermal separation of material on the properties of the surface layers. The separation of material is an integral part of a preparation of all final products. During cutting the surface layer of the separated material is effected, which then has an influence on the sequence of the following operations. The method of thermal separation of material was selected for the experiment described in the article a method of flame cutting. The material selected for the method was a common steel ČSN 411373, which is industrially produced and processed. The effect on the material was shown by measuring micro-hardness using the micro-hardness tester DM 2D.