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Surface irrigation methods need less capital investment and energy than pressurized systems, and therefore they have a wide range of use in many regions. However, inaccurate system design and irrigation applications lead to non-uniform distribution of water in the soil profile. Therefore, the water loss caused by deep percolation increases, and the water application efficiency decreases. In this investigation, a new method was devised for the optimum design of a blocked end furrow system. The new method simulates the movement properties of water in the soil. It analyzes interactively and simultaneously the infiltration characteristics of the soil, the inflow to the furrow and the irrigation water requirement of the crop. The spatio-temporal variation of the wetting pattern which occurs during the water application period and of the components of the wetting pattern can be determined momentarily for any time point during the irrigation application. This process is carried out by running the movement equations of water in the soil, which are described in this investigation. The proposed method was run for two different sample applications of blocked end furrow systems without slope. In the verification process of the model, the sample applications were compared with the results of the USDA SCS method. The results from the two different methods were compared and analyzed in detail. In conclusion, the results from the proposed method gave the optimum solution for different conditions.

A simple, versatile, and economical method development with matrix elimination to determine the elements As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn in seawater by using the technique of inductively coupled plasma mass spectrometry is reported. Real seawater was used as a matrix for the standard adding calibration and other validation parameters. The samples were open digested at 80 °C with 2 mL HNO

Bu çalışmada, farklı biyokütle atıkları kullanılarak aktif karbon ilk defa ani (flaş) ısıtma yöntemi ile üretilmiştir. Ani ısıtma yöntemiyle üretilen aktif karbonlar, sulu çözeltiden amoksisilin gideriminde adsorbent olarak kullanılmıştır. Adsorpsiyon deneyleri sonucunda elde edilen verilere farklı adsorpsiyon izoterm ve kinetik modelleri uygulanmış ve adsorpsiyon termodinamiği araştırılmıştır. Üretilen aktif karbonların amoksisilin (AMX) adsorpsiyon kapasitesi 300-500 mg/g arasında bulunmuştur. Sonuçlar değerlendirildiğinde, ani (flaş) ısıtma yöntemiyle yüzey alanı ve mikrogözenekliliği yüksek aktif karbonların amoksisilin gideriminde etkili bir adsorbent olarak kullanılabileceği belirlenmiştir.

Mechanistic modeling of the milling forces is described by a set of cutting and edge force coefficients that characterize the shearing and ploughing actions of the metal removal process. The force coefficients are traditionally calibrated under a series of dedicated milling experiments. However, due to the force coefficients’ process-dependency, such an approach can become cumbersome if the machining conditions deviate from those of the milling experiments. In this paper, a method for monitoring the in-process force coefficients is proposed for toolpaths that exhibit varying radial immersions or feed rates. The proposed methodology was experimentally validated, and it is demonstrated that the edge force coefficients can be used to estimate the tool's flank wear. In the absence of a force dynamometer, force coefficients as estimated under spindle current measurements were evaluated and also shown to be a viable solution for tool wear monitoring.

Yoghurt is a good dietary source of macro and micro minerals. However, the mineral content of yoghurt can vary according to the technological processing used in its manufacture. In this context, the aim of this study was to compare some macro (Ca, K and Mg) and micro (As, Cd, Co, Fe, Mn, Ni, Pb, Se, V and Zn) mineral contents of total solids-standardized yoghurts with four different methods by following: (1) Addition of skim milk powder to milk, (2) Concentration of yoghurt milk by vacuum evaporation, (3) Concentration of yoghurt curd in a cloth bag and (4) Concentration of yoghurt curd by mechanical centrifugation. The highest content of the macro minerals was in the yoghurt produced with method 1, while the highest content of most of the micro minerals was in the yoghurt produced with method 4. The results of this study showed that the mineral content of yoghurt could be modified by the method used in the manufacture of yoghurt to standardize total solids content., Jogurt je dobar prehrambeni izvor makro i mikro elemenata. Međutim, udio mineralnih tvari u jogurtu može varirati ovisno o tehnološkoj obradi koja se koristi pri njegovoj proizvodnji. U skladu s tim, cilj ove studije bio je usporediti sadržaj nekih makro (Ca, K i Mg) i mikro (As, Cd, Co, Fe, Mn, Ni, Pb, Se, V i Zn) elemenata u suhoj tvari jogurta standardiziranom primjenom sljedeće četiri metode: (1) dodavanjem obranog mlijeka u prahu; (2) koncentriranjem mlijeka uparivanjem u vakuumu; (3) koncentriranjem koaguluma jogurta u sirarskoj vreći; i (4) koncentriranjem koaguluma jogurta mehaničkim centrifugiranjem. Najveći sadržaj makro elemenata utvrđen je u jogurtu proizvedenom metodom 1, dok je najveći sadržaj većine mikro elemenata utvrđen u jogurtu proizvedenom metodom 4. Rezultati ove studije pokazali su da se sadržaj mineralnih tvari u jogurtu može podešavati primjenom različitih metoda standardizacije suhe tvari.

Postoperative delayed diaphragmatic hernia (DH) is a rare and uncommon event after adult orthotopic liver transplantation (OLT), which however could be potentially life-threatening complication, especially in the absence of early and correct diagnosis and appropriate surgical treatment. We present a case of 48 year-old male with left diaphragmatic herniation of left part of transverse colon, who thirty nine months before underwent OLT with right-sided allograft implantation and which was recently successfully managed by open abdominal approach in our institution. The postoperative course was uneventful and he was discharged at the 8th day after surgery. Our case illustrates, that delayed DH after the OLT in adults could be a new problem, which affect transplant recipients with long-term follow-up period. Hence, we consider, that once the diagnosis of DH is confirmed, the patient should be operated immediately, in order to avoid the possible life-threatening complications.

Biliary complications (BCs) are still a major cause of morbidity following liver transplantation despite the advancements in the surgical technique. Although Roux-en-Y (RY) hepaticojejunostomy has been the standard technique for years in pediatric patients, there is a limited number of reports on the feasibility of duct-to-duct (DD) anastomosis, and those reports have controversial outcomes. With the largest number of patients ever reported on the topic, this study aims to discuss the feasibility of the DD biliary reconstruction technique in pediatric living donor liver transplantation (LDLT). After the exclusion of the patients with biliary atresia, patients who received either deceased donor or right lobe grafts, and retransplantation patients, data from 154 pediatric LDLTs were retrospectively analyzed. Patients were grouped according to the applied biliary reconstruction technique, and the groups were compared using BCs as the outcome. The overall BC rate was 13% (n = 20), and the groups showed no significant difference (P = 0.6). Stricture was more frequent in the DD reconstruction group; however, this was not statistically significant (P = 0.6). The rate of bile leak was also similar in both groups (P = 0.6). The results show that the DD reconstruction technique can achieve similar outcomes when compared with RY anastomosis. Because DD reconstruction is a more physiological way of establishing bilioenteric integrity, it can safely be applied.

In present study, the levels of some toxic elements in 19 different home-made cosmetic products (spray hair dye, henna, tattoo, eyeliner, eye mascara, smear, lip moisturizer, and lipstick) were analyzed by inductively coupled plasma mass spectrometric (ICP-MS) after microwave digestion. The ICP-MS results were verified by the analyzing certificated reference material (EnviroMAT Drinking Water, High).The detection limit (LOD) was set from 0.1 to 0.2 and the quantification limit (LOQ) from 0.2 to 0.8 μg L−1 and the recoveries estimated from 99% to 109%. The relative standard deviation (RSD) (%) for elements was determined in the range of 0.9 and 2.1%. Although various concentrations of arsenic (As),cadmium (Cd), cobalt (Co), chromium (Cr), cupper (Cu), and nickel (Ni) were determined in some samples, lead (Pb) concentration was found in all the samples. Data obtained were compared with the permissible limit of cosmetic products by the WHO. The concentration of Pb in smear samples was higher than the permitted limit created by the WHO, and Ni concentration in the some samples exceeds the limit set by the WHO. The rank order of toxic elements based on THQ index was Cr > Pb > Ni. The potential non-carcinogenic was considerably lower than the safe risk limits (THQ > 1).

Online learning can be useful for designing instruction with its asynchronous or synchronous forms. The teachers can reduce time and space limitations and support learners with additional materials in a cost-effective way. However, online learning heavily depends on learner characteristics/profile and course design. Even though it provides the flexibility of designing courses for different learner needs, motivation and learner responsibility remain unsolved problems. On the other hand, we can boost learner's autonomy with our course design. Autonomous learner profile is a perfect fit for online learning because of the flexibility for the learners. In this chapter, the authors define learner autonomy, describe its role in online course design, go over key elements in online course design and management, and give design tips for boosting learner autonomy in both synchronous and asynchronous online courses.

Variable pitch and helix end mills disturb the regeneration mechanism that causes chatter vibrations, and as such, they enable stable, high-performance, and high material removal rate milling processes. The regeneration mechanism is altered by the non-uniform tool geometry that results in multiple or distributed delays between vibrations imprinted on the machined surface. The design procedure for these cutters needs characterization of the stability diagrams to decide the non-uniform geometry that improves the absolute minimum stable depth of cut as well as the changes in the size and location of stability pockets. This paper presents a unified method to rapidly analyze the stability of variable helix and pitch cutters with multiple or distributed delays using a non-iterative multi-frequency domain approach that uses the Nyquist criterion to check stability at every spindle speed and depth of cut tuple. Predictions are benchmarked with the established and widely used semi-discretization method and verified with previously published experimental data, which are further validated by our own experiments. The proposed method is as accurate as of the established one while offering computational savings of up to 94%. Since explorations of alternate and better designs were potentially precluded by the computational inefficiency of previous methods, and since the method proposed herein is fast and accurate, it can help to accelerate the design of improved variable helix and pitch end mills for their use in industrial settings.

This paper presents a strategy to virtually predict and constrain the contouring errors contributed by cutting force disturbances on feed drives. The tracking errors on each feed drive are predicted as a linear function of tangential feed by evaluating the product of estimated power spectrum of cutting forces and disturbance frequency response function along the tool path in virtual CAM environment. The corresponding tool tip contouring and tool axis orientation errors are estimated and constrained by scaling the feed along the tool path. The algorithm is experimentally illustrated to improve the machining accuracy on a 5 Axis CNC machine tool.

Magnetic chitosan beads and quartz crystal microbalance chip were decorated with lysozyme specific aptamer for isolation and detection of lysozyme, respectively. The lysozyme specific aptamer was immobilized on poly (dopamine) coated magnetic chitosan beads and the chip via Schiff base reaction. The percentage of the removal efficiency and purity of the isolated lysozyme from egg white were 87.6% and 91.8%, respectively. Further, the sensor system was contacted with different concentrations of lysozyme and other test proteins. This sensor system provided a method for the label-free, concentration-dependent, and selective detection of lysozyme with an observed detection limit of 17.9 +/- 0.6 ng/mL. The sensor system was very selective and not significantly responded to the other tested proteins such as ovalbumin, trypsin, cytochrome C, and glucose oxidase. The prepared new sensor system showed a good durability and a high sensitivity for determination of lysozyme from solutions and whole egg white.

Surface errors due to force-induced tool and workpiece deflections are one of the major errors in multi-axis machining of parts especially with thin-walled structures. Dominant approaches to reduce these surface errors are re-machining the part, feed scheduling, and tool path modification. These methods are time consuming and computationally costly, and they rely on experimental data which is used in cutting force and deflection predictions. The present paper introduces a pure geometrical approach to reduce surface errors drastically by minimizing the engagement lengths of flutes’ cutting edges when a point on the flute’s cutting edge is in contact with the design surface. The total engagement length of the flutes’ cutting edges when one of them generates a contact point on the workpiece surface is formulated and considered as the minimization objective function of an optimization problem. Tilt and lead angles, which define the tool orientation, are the design variables of the optimization problem subjected to constraints based on the geometrical requirements of the ball end milling process. The optimization problem uses the nominal tool path to generate an optimal tool path with adjusted tool orientations. The presented method is computationally inexpensive and does not need any experimentally calibrated coefficients to predict cutting forces because of the pure geometrical nature of the approach. The method is experimentally validated through five-axis ball end milling experiments in which more than 90% surface error reduction is achieved.

Five-axis ball-end milling is used extensively to machine parts with sculptured surfaces. This paper presents the general cutting dynamics model of the ball-end milling process for machine tools with different five-axis configurations. The structural dynamics of both the tool and workpiece are considered for the prediction of chatter stability at each tool location along the tool path. The effects of tool–workpiece engagement and tool axis orientation are included in the model. By sweeping the spindle speeds, the chatter-free spindle speeds are selected followed by the prediction of forced vibrations in five-axis milling of thin-walled, flexible parts. The proposed model has been experimentally illustrated to predict the chatter stability and forced vibrations on a table-tilting five-axis computer numerical control machine tool.

This paper reviews the dynamics of machining and chatter stability research since the first stability laws were introduced by Tlusty and Tobias in the 1950s. The paper aims to introduce the fundamentals of dynamic machining and chatter stability, as well as the state of the art and research challenges, to readers who are new to the area. First, the unified dynamic models of mode coupling and regenerative chatter are introduced. The chatter stability laws in both the frequency and time domains are presented. The dynamic models of intermittent cutting, such as milling, are presented and their stability solutions are derived by considering the time-periodic behavior. The complexities contributed by highly intermittent cutting, which leads to additional stability pockets, and the contribution of the tool's flank face to process damping are explained. The stability of parallel machining operations is explained. The design of variable pitch and serrated cutting tools to suppress chatter is presented. The paper concludes with current challenges in chatter stability of machining which remains to be the main obstacle in increasing the productivity and quality of manufactured parts.

Thanks to technological developments, distance education helped new techniques and strategies to emerge in the instruction field. However, these developments may cause problems about integration of the interaction between students and instructors. Communication is seen as one of the biggest problems. Instructors' online communications and their attitudes towards this process affect quality of teaching and learning processes. Other factors affecting this process are learning environment and its effective use. This study is designed to incorporate a mixed method with the aim of reflecting instructors' experiences about different communication techniques and learning environments. In scope of this research, the researchers planned a four-week process using the communication that the researchers have been establishing with Ege University Faculty of Education's instructors. The researchers will use different mobile devices and feedback methods for the process.

Thin-walled parts with double-sided features are widely used in many industrial sectors but their machining is particularly time consuming and challenging. Collaborative machining is a new paradigm in the development of industrial 4.0. It can potentially revolutionize the existing thin-walled part machining methods, leading to higher productivity, flexibility and sustainability. For this end, this paper introduces a novel concept with dual parallel kinematic machines (PKMs) collaboratively performing synchronized and asynchronized cutting and support from both sides of a thin-walled part, without changeover/re-clamping of the workpiece. Compared to the conventional single-sided machining, this study shows that static and dynamic performances of the workpiece are significantly improved under the dual PKM collaborative operation. A case study of milling a thin-walled part with double-sided features was conducted by PKMs under three comparative strategies, namely, double-sided synchronized milling, alternative single-sided milling, and sequential single-sided milling. Experimental results show that the novel double-sided synchronized milling strategy by dual collaborative PKMs produced the best dimensional accuracy and satisfactory surface quality due to the improved static stiffness and dynamic performance, and balanced deflections. More importantly, a two-fold greater productivity has been achieved as the novel strategy doubles the material removal rate while eliminating the cumbersome in-process steps used in conventional single-sided machining.

In this work, magnetic chitosan (MCH) beads were synthesized by phase-inversion method, and grafted with polydopamine (PDA) and then used for direct immobilization of Candida rugosa lipase by Schiff base reaction. The amount of immobilized enzyme and the retained activity were found to be 47.3 mg/g and 72.8%, respectively, at pH 7.0, and at 25 degrees C. The apparent Km (9.7 mmol/L), and Vmax (384 U/mg) values of the immobilized lipase were significantly changed compared to the free lipase. The MCH@PDA-lipase was better thermal and storage stability at different temperatures than those of the free lipase. In hexane medium, the esterification reaction results showed that the maximum conversions of isoamylalcohol and isopentyl alcohol to isoamyl acetate and isopentyl acetate using the MCH@PDA-lipase were found to be 98.4 +/- 1.3% and 73.7 +/- 0.7%, respectively. These results showed that the MCH@PDA-lipase can be used as an operative immobilized enzyme system for many biotechnological applications.

Red pepper is used as raw material in industry and as a seasoning in various foods. In this study, the cadmium, lead and arsenic content of 33 red pepper samples sold in open and sealed packages on different markets was investigated in terms of their synthetic color components, aflatoxin amounts and toxic elements, which have been declared as cancerous by the World Health Organization (WHO). According to the results, synthetic colorants, arsenic and cadmium were not detected in any of the samples, while lead was detected in 11 samples and aflatoxins were detected in eight of the samples. As a consequence of these investigations, a health risk analysis was carried out by taking into account the amount of consumption in the region. The B1 aflatoxin content in the samples, according to daily consumption data, exceeded the limits set by the European Commission (EC) by almost 150%.

Objectives Living-donor liver transplant for BuddChiari syndrome is particularly challenging because of the need for venous outflow reconstruction as grafts from living donors lack vena cava. In addition, recipient vena cava may be thrombotic and fibrotic to such an extent that it would not allow graft venous outflow reconstruction. Under these circumstances, the right atrium provides an easily accessible alternative for venous outflow reconstruction, omitting the need for vena cava replacement. Materials and methods Data from 3 patients who were treated using this technique were collected and evaluated with regard to surgical technique and outcomes. Results All patients were alive without vascular complications after a mean follow-up of 67 months. The applied surgicaltechnique was similar except with regard to vena cava preservation. Conclusions During the natural course of the disease, venous collaterals form as chronic thrombosis extends into the vena cava. The vena cava can be safely resected in these patients to facilitate hepatectomy through dense adhesions, which is another common clinical problem in this disease. Consequently, venous outflow reconstruction to the right atrium creates the feasible opportunity of draining the graftliver without having to replace the vena cava.

There is a paucity of data in respect of the nutritional quality of complementary foods for infants and young children aged between 6 and 12 months. In this study, we developed and validated an analytical method for determination of the endocrine-disrupting organochlorine pesticides (OCPs) and elements (As, Cd, and Pb) in infant formula and baby foods. Therefore, it found out the contamination level of the both OCPs and some trace metals (As, Cd, and Pb) in widely consumed infant formula and baby food in Turkey. Metal concentrations in baby foods and infant formula were determined by inductively coupled plasma mass spectrometry. Samples were digested with nitric acid and hydrogen peroxide in a microwave oven. Determination of 24 organochlorine pesticide residues in baby foods and infant formula was completed by using gas chromatography double mass spectrometry. QuEChERS extraction method was carried out in the sample preparation part. The analytical performance of the entire procedure, such as linearity, the detection of limit, limit of quantification, specificity/selectivity, recovery (%), and precision, were assessed. The recoveries ranged from 93% (As) to 100% (Pb) for elements 78–98% for organochlorine pesticide residues (OCPs) at 100 ng mL−1. According to the results, lead, cadmium, and pesticides were not detected in any of the samples, while arsenic was detected in 16 samples.

This paper presents a general and unified model which predicts tool – workpiece engagement, chip geometry, cutting forces, chatter stability and hole surface errors simultaneously. The tool-workpiece engagement along the tool path is identified by a newly introduced, computationally fast line-intersection algorithm and used in predicting the chip thickness. The contribution of bottom edges to the cutting process is included. The dynamics of the system have been modeled including time-varying delay contributed by the combination of spindle speed and orbital tool motion. The stability of the orbital drilling is solved in discrete-time and frequency domains. Three dimensional stability lobes and hole surface errors are predicted as a function of tool position along the orbital path, spindle speed and pitch length of the path. The mechanics, stability and surface location error models have been experimentally validated by conducting orbital drilling of holes. The model is intended for optimal selection of tool geometry, orbital and tangential feeds, and spindle speeds without causing chatter, violating dimensional tolerances and overloading of the machine.

WOS: 000427075700013, PubMed ID: 29391313, Background/Aims: A liver transplant is the preferred treatment for patients with end-stage liver disease, as it usually results in long-term survival. However, due to the use of chronic immunosuppressive therapy, which is necessary to prevent rejection, de novo cancer is a major risk after transplantation. The aim of this study was to assess the incidence of post-transplant malignancies in children after liver transplantations. Materials and Methods: The study group consisted of 206 liver transplant recipients, with no history of cancer, including hepatocellular carcinoma, in two liver transplantation centers in Turkey between 1997 and 2015. Data were obtained from patient's data chart. Results: In the study group, de novo cancer was diagnosed in 13 of the 206 patients. Post-transplant lymphoproliferative disease (PTLD) occurred in seven (53.8%) patients and other malignancies in six of the 13 patients. The types of PTLD were as follows: B-cell origin (n= 2), Epstein-Barr virus (EBV)-related (n= 2), T-cell origin (n= 1), and Hodgkin's lymphoma (n= 2). EBV DNA was isolated from seven patients, three of whom developed PTLD. The others developed Kaposi's sarcomas, Burkitt's lymphomas, cutaneous large-cell lymphomas, Hodgkin's lymphomas, and liver sarcomas. Conclusion: After transplantation, immunosuppressive treatment is unavoidable, increasing the risk of malignancies. However, a close follow-up and periodic screening can reduce cancer-related mortality and morbidity.

Change is a growing phenomenon in the era we live. The issue of change has been one of the topics of interest in the field of administration. In general, change refers to transfer from the present situation to another situation and differentiation. Implementations related to the change also affect today's education systems. School administrators, primarily, can be shown responsible for the implementation of changes in educational institutions. The purpose of this research is to understand how the change in educational institutions is assessed in the school administrator and the environment context. The participants of the research are 12 administrators who are determined among the administrators of educational institutions working in the central districts of Konya province (Karatay, Meram, Selcuklu) and from different socio-economic districts and in the spring term of 2015-2016 academic year. During the publication phase, the interviews are reviewed and the participants' approval for publication is asked. This study has been carried out within the framework of phenomenological design and the qualitative case sampling is preferred among from purposeful sampling methods. In the analysis of the data, descriptive analysis technique is used. As a result of the research, it is understood that the school administrators have adopted the phenomenon of change and have taken this fact into account in their work. It is understood that making new arrangements in the existing structure will be reflected positively in the school and that the surrounding area should also be taken into consideration.

Background Venous reconstruction in living-donor liver transplantation for Budd-Chiari syndrome (BCS) has challenges because the grafts from living donors lack vena cava, and hepatic venous anastomosis must be performed on an already-thrombosed and/or stenosed inferior vena cava. Several techniques are described to overcome this problem, and we represent our experience with 22 patients. Methods Medical recordings of 22 patients were retrospectively collected, and disease-specific data as well as recordings about surgical technique were analyzed. Results Creation of a wide, triangular de novo orifice was the main method used for venous drainage, which was used in 19 patients. The remaining 3 patients had totally thrombosed vena cava; thus, direct anastomosis to the supra-hepatic portion of the vena cava was used in 2 patients and an anastomosis to the right atrium was used in 1 patient. Conclusions Venous reconstruction in BCS can be achieved without the use of patch-plasty, and the inferior vena cava can be safely resected in selected patients. Living-donor liver transplantation is a feasible option for the treatment of BCS, considering the scarcity of cavaderic donors.

Lathyrus sativus L. is considered one of the most promising calorie and protein sources for the vast, expanding populations living in drought-prone and marginalized areas of the world. This study was conducted to determine the β-N-oxalyl-L-2,3-diaminopropionic acid (β-ODAP), L-homoarginine, and asparagine content of a total of 173 Lathyrus sativus L. genotypes, of which 93 were collected under natural conditions in Antalya. The β-ODAP, L-homoarginine, and asparagine content of Lathyrus sativus L. genotypes ranged from 1.55 to 20.8 mg/g seeds, 1.35 to 11.64 mg/g seeds, and 0.59 to 5.22 mg/g seeds, respectively.