bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the Cutting Temperature of the Textured Tool by 3D FEA Simulation
Authors: TANG Siwen , LIU Pengfei , WANG Rui , NIU Qiulin , YANG Guoqing , LIU Wenhui , LIU Qian
Published: April 2020

Temperature plays an important role in the life of cutting tools. However, it is sometimes difficult to observe instantaneously because of limited data acquisition, especially for the textured tool. In this paper, the performance of microgroove textured cutting tools for three-dimensional (3D) oblique dry turning of AISI 1045 steel was studied by finite element simulation. The effects of width, depth and spacing of strip micro-texture on cutting temperature and the effect of cutting speed on cutting temperature of strip micro-texture tool were studied. The results show that the maximum temperature of the tool and the tip temperature first increase and then decrease with the increase of micro-texture width. When the micro-texture depth increases, the maximum temperature and the tool tip temperature decrease first and then increase. The highest temperature and tip temperature of the tool gradually increase with the increase of micro-texture spacing. The highest temperature and tip temperature of the tool increase with the increase of cutting speed, feed speed and cutting depth. In addition, the effective mechanism of micro-texture parameter for the temperature was proposed. It provides profound guidance for optimizing the microstructure parameters and cutting process of cutting tools according to cutting temperature in this study. It also provides an effective and practical method for the design, innovation and development of micro-textured tools.
Tribological Property Study of Xanthate Acetic Ester in Hydrogenated Oil
Authors: LEI Juanhong , LIU Jian , XIONG Liping , YANG Xue , HE Zhongyi
Published: April 2020

Xanthate was used as an initial reactant to synthesis two kinds of novel xanthate-containing acetic ester additives (HX and OX), and a four-ball machine was used as tribological tester to appraise their tribological behaviors in hydrogenated oil (10cst). The test results indicated that the as-synthesized additives possess good extreme pressure, antiwear and antifriction properties. The shorter carbon chains acetic ester, the better tribological properties the higher sulfur content. The action mechanism was estimated by analysis of the XPS (X-ray photoelectron spectroscopy) and SEM (scanning electron microscope) results of the worn steel ball surface, and the results illustrated that the protective film containing ferric sulfide and ferric sulfate compound was formed on the worn steel ball surface by xanthate acetic ester , and the protective film has good tribological properties.
Poczucie szczęścia studentek kierunków pedagogicznych polskiej i ukraińskiej uczelni: badanie porównawcze
Authors: Durkalevych Iryna
Published: April 2020

We współczesnej literaturze psychologicznej dużo miejsca poświęca się tematowi szczęścia, który ciągle zyskuje zainteresowanie wśród badaczy. Wyniki licznych zagranicznych badań wykazują, że subiektywny dobrostan koreluje z wdzięcznością, samooceną, aktywnością, kreatywnością, sprzyja uczeniu się, osiąganiu sukcesów oraz pomyślnemu rozwojowi relacji społecznych i in. Jednak trudno znaleźć badania, które dotyczyłyby problematyki szczęścia w odniesieniu do studentów kierunków pedagogicznych, zwłaszcza w kontekście międzynarodowym. Artykuł wpisuje się w określoną problematykę, prezentując wyniki badania porównawczego subiektywnego dobrostanu studentek kierunków pedagogicznych polskiej i ukraińskiej uczelni. Główna problematyka badawcza koncentrowała się wokół pytania: jaki jest poziom szczęścia studentek kierunków pedagogicznych polskiej i ukraińskiej uczelni. Podstawą teoretyczną jest teoria subiektywnego dobrostanu Dienera. Badanie przeprowadzono wśród 100 studentek (50 Polek i 50 Ukrainek) za pomocą Skali Satysfakcji z Życia (SWLS) autorstwa Dienera, Emmonsa, Larsena i Griffin w adaptacji Juczyńskiego.
Circulating Vascular Endothelial Growth Factor (VEGF) Levels in Advanced Stage Cancer Patients Compared to Normal Controls and Diabetes Mellitus Patients with Critical Ischemia
Authors: Kusumanto Yoka H. , Meijer Coby , Dam Wendy , Mulder Nanno H. , Hospers Geke A.P.
Published: April 2020

Anti-angiogenic therapy is emerging as a valuable tool in the treatment of patients with cancer. As VEGF is a central target in anti-angiogenic therapy, its levels in the circulation might be relevant in selecting tumor types or patients likely to respond to this treatment. Additional VEGF has been recognized as a key factor in the pathogenesis of diabetic retinopathy. Recently anti-angiogenic therapy has been advocated in this situation. We measured VEGF levels in whole blood in 42 patients with high grade (n = 26) and low grade (n = 16) end stage cancer, and in 28 healthy controls and 37 patients with diabetes related vascular disease. Only 2/26 patients in the group of high grade cancer had signifi  cantly elevated VEGF levels, 1/16 in the low grade group and 1/28 in the healthy control group. In contrast, in 10/37 diabetic patients the mean VEGF levels were signifi  cantly elevated compared to the other groups. The mean level in these diabetic patients was signifi  cantly elevated compared to the other groups. These data indicate the limitation of the use of circulating VEGF levels as a potential selection criterion for anti-angiogenic therapy in cancer patients and suggest further studies into its application in the management of diabetic complications.
A Case of Organizing Pneumonia (OP) Associated with Pembrolizumab
Authors: Fragkou Paraskevi , Souli Maria , Theochari Maria , Kontopoulou Christina , Loukides Stelios , Koumarianou Anna
Published: April 2020

Until recently, chemotherapy for metastatic melanoma had disappointing results. The identification of immune checkpoints such as CTLA-4 and PD-1/PD-L1 has led to the development of an array of monoclonal antibodies (Mabs). These immunologic approaches against tumoral cells come with a novel kind of side effects that the clinician needs to be familiarized with. Herein, we report for the first time a case of organizing pneumonia, based on imaging and cytological analyses of bronchoalveolar lavage, possibly associated with the use of pembrolizumab, an anti-PD-1 Mab recently approved for the treatment of metastatic melanoma.
LASTİK SEKTÖRÜNDE OWAS VE NASA-TLX YÖNTEMLERİ KULLANILARAK FİZİKSEL VE ZİHİNSEL İŞ YÜKÜ ÖLÇÜMÜ
Authors: ÖZCAN Burcu , YEĞİN Enes
Published: April 2020

Kas iskelet sağlığına ilişkin problemler işyerlerinin dikkate alması gereken önemli bir konu olarak karşımıza çıkmaktadır. İşle ilgili hatalı duruşlar işçilerin zorlanmasına ve rahatsızlıkların ortaya çıkmasına neden olur. Bu noktada kötü çalışma duruşlarını analiz edebilmek amacı ile Ovako Çalışma Duruşu Analiz Sistemi (OWAS) yöntemi kullanılmaktadır. Bu teknik ile vücut pozisyonlarını tanımlanır ve zorluk derecesine göre puanlama yapılır. İyileştirme önerileri ile problemler ortadan kaldırılmaya çalışılır. Bu makalede otomotiv sektörüne lastik üreten bir işletmede yükleme ve boşaltma yapan çalışanların uygun garip çalışma duruşu olarak adlandırılan çalışma pozisyonlarının ve buna bağlı olarak zihinsel iş yüklerinin iyileştirilmesi için OWAS ve NASA-TLX yöntemleri kullanılmış olup ergonomik olmayan hareketler tespit edilmiştir. Bu zorlanmaları azaltacak ya da yok edecek aksiyonlar önerilmiş olup uygulamaya konulmuştur.
SÜRDÜRÜLEBİLİR BİNALARA YEŞİL ERGONOMİ ÇERÇEVESİNDEN BİR BAKIŞ: KONYA GIDA VE TARIM ÜNİVERSİTESİ KAMPÜSÜ
Authors: ARAT Yavuz , KAÇAR Ayşenur
Published: April 2020

Sanayi devrimi sonrası gelişen teknoloji, hızlı ve kontrolsüz artan insan nüfusu etkisiyle 19. yüzyıldan günümüze kadarki süreçte tüketim hızlı bir biçimde artmıştır. Bu durum; doğal kaynakların bilinçsizce tüketilmesi, hızlı kentleşme, su ve havanın kirletilmesi, azalan yeşil alan sorununu beraberinde getirmiştir. Yaşanan bu gelişmeler sonrası canlıların yaşam alanı ve sağlığı için birçok tehdit oluşmaya başlamıştır. İnsanlar oluşan bu tehditlere çözüm yolu bulma amacıyla kaynakların verimli bir şekilde kullanımı ve doğa tahribatının azaltılması hususunda arayış içesine girmiştir. Bu arayışın bir sonucu olarak “sürdürülebilirlik” kavramı ortaya çıkmıştır. Sürdürülebilirlik kavramı, ortaya atıldıktan sonra yapı ölçeğinde de sürdürülebilirlik tanımı yapılmış, çeşitli ölçütler getirilmiştir. Bu ölçütler doğrultusunda çevre faktörü daha çok dikkate alınarak, ergonomi bilimi içerisinde de önem kazanması sağlanmıştır. Ergonominin çevresel boyutu üzerine yapılan tartışmalar, yeşil ergonomi kavramını ortaya çıkarmıştır. Bu kapsamda çalışmada; sürdürülebilirlik, yeşil ergonomi ve yeşil bina kavramları üzerinde durularak ergonomi ile ilişkisi sorgulanmış, örnek alan üzerinden yorumlanarak anlamlandırılmıştır. Örnek alan olarak Konya’da bulunan “sürdürülebilir mimari” ilkesiyle tasarlanan “Konya Gıda Tarım ve Üniversitesi Kampüsü” seçilmiştir. Kampüs, öncelikle LEED (Enerji ve Çevre Dostu Tasarımda Liderlik) ana başlıkları altında, EcoBuild danışmanlık şirketi tarafından hazırlanan puan tablosu doğrultusunda incelenmiştir. Buradan çıkan sonuçlar dâhilinde kullanıcı refahı ve sağlığı için önem taşıyan “yeşil ergonomi” açısından bir bakış sunulmuştur. Yapım aşaması tamamlanmamış kampüsün ileri süreçte LEED Gold Sertifikaya sahip olabileceği öngörüldüğünde kampüsün yeşil ergonomi kriterleri eşliğinde analizinin yapılması çalışmanın önemini ortaya koymaktadır.
KOLTUK İMALATINDAKİ ZORLANMALARIN BAUA YÖNTEMİ İLE DEĞERLENDİRİLMESİ
Authors: ÜLKER Onur
Published: April 2020

Bu çalışmanın amacı, ülkemizdeki mobilya imalatında çalışanların yatay ve dikey olarak parça taşımaları esnasında karşılaştıkları zorlanmaları araştırmak ve çalışanlar üzerindeki etkilerine dikkat çekmektir. Zorlanma sınır değerlerinin ölçümü için mevcut yöntemler araştırılmış, Federal Almanya İş Güvenliği ve İş Hekimliği Kurumu (BAUA)’nun geliştirmiş olduğu yöntem seçilmiş ve kas iskelet sistemindeki zorlanmalar için hesaplamalar yapılmıştır. Mobilya sektöründe üretim, makine parkı ve insan gücüne dayanmaktadır. Mobilya sektöründe insan gücü kullanımı parça taşımanın yanı sıra makineye parça verme, makineden parça alma, kaldırma ve indirme işlemlerini kapsamaktadır. Bu süreçteki taşıma ve kaldırma işlerinin ergonomik koşullara uygunsuzluğu iş kazalarına ve meslek hastalıklarına yol açmaktadır. Buna bağlı olarak işletmede iş gücü kaybı yaşanmakta, üretim aksamakta ve işletme açısından maliyetler artmaktadır. Araştırma sonuçları ile, mobilya üreten işletmelerde, iş kazalarının ve meslek hastalıklarının engellenebileceği düşünülmektedir. Bu şekilde mobilya üretim tesislerinin çalışma standardının yükselmesi ve verimliliğin artırılması sağlanabilir.
Budaya dan Pengaruh Oranglain yang Memengaruhi Sikap Ibu dalam Pemberian MP-ASI di Puskesmas Tuntang
Authors: Dwi Saputri Tyas Yesiana
Published: April 2020

ABSTRAK

 

Pada balita usia 6 bulan keatas, ASI sebagai sumber nutrisi sudah tidak mencukupi lagi maka perlu diberikan makanan pendamping ASI(MP-ASI) agar kebutuhan gizinya terpenuhi. Sikap ibu yang baik sangat dibutuhkan selama proses pengenalan makanan untuk bayi. Berdasarkan data dinas kesehatan Kabupaten Semarang tahun 2016 cakupan tertinggi gizi kurang berada di Puskesmas Tuntang sebesar 19 balita dan berdasarkan hasil studi pendahuluan 3 ibu belum ada rencana pemberian MP-ASI karena usia anaknya belum ada 6 bulan, sehingga dapat disimpulkan bahwa sikap ibu dalam pemberian MP-ASI masih kurang atau negatif. Tujuan penelitian ini adalah untuk mengetahui Gambaran Faktor-Faktor yang memengaruhi Sikap Ibu dalam Pemberian MP-ASI Di Puskesmas Tuntang.

Rancangan penelitian ini menggunakan penelitian deskriptif kuantitatifdengan pendekatan cross sectional. Pengambilan sampel dengan teknik purposive sampel, jumlah sampel 64 responden.

Ibu memiliki sikap positif dalam pemberian MP-ASI di Puskesmas Tuntang yaitu sebanyak 34 (53,1%) ibu dan sikap negatif sejumlah 30 (46,9%). Sikap positif ibu berdasarkan Pengaruh Orang Lain yang Dianggap Penting dalam pemberian MP-ASI sebanyak 32 (50%) ibu dan sikap negatif 32 (50%) ibu. Sikap positif ibu berdasarkan pengaruh budaya dalam pemberian MP-ASI sebanyak 35 (54,7%) ibu dan sikap negatif 29 (45,3%) ibu. Sehingga dapat disimpulkan bahwa sikap ibu dalam pemberian MP-ASI di Puskesmas tuntang berdasarkan pengaruh budaya  sebagian besar memiliki sikap positif yaitu 35 (54,7%) ibu dan berdasarkan pengaruh orang lain yang dianggap penting sebanyak 32 (50%) memiliki sikap positif.
Hyperanalyticity of space-time
Authors: Rybnikov Aleksandr
Published: April 2020

New mathematical object - hyperanalytic function is introduced. The convergence of hyperanalytic functions is substantially above than the convergence of analytic functions. A specific sample of hyperanalytic function is the reticulum function (RF). This function describes the reticulum space-time. RF can't be decomposed into the Fourier series and, therefore, RF does not provide the conservation of parity as the analytic functions do. Thanks to this, the RF can be decomposed in an endless series of two primitive hyperanalytic functions by sequential attempts of decomposition in the even and odd functions. The unique parameter of such series is the fine structure constant $\alpha$. It allows combine all fundamental interactions into the Naturally-Unified Quantum Theory of Interactions. The price of such quantum unification is the reticulum space-time.
On the $x$--coordinates of Pell equations that are products of two Lucas numbers
Authors: Ddamulira Mahadi
Published: April 2020

Let $ \{L_n\}_{n\ge 0} $ be the sequence of Lucas numbers given by $ L_0=2, ~ L_1=1 $ and $ L_{n+2}=L_{n+1}+L_n $ for all $ n\ge 0 $. In this paper, for an integer $d\geq 2$ which is square-free, we show that there is at most one value of the positive integer $x$ participating in the Pell equation $x^{2}-dy^{2}=\pm 1$ which is a product of two Lucas numbers, with a few exceptions that we completely characterize.
On the $x$--coordinates of Pell equations which are sums of two Padovan numbers
Authors: Ddamulira Mahadi
Published: April 2020

Let $ \{P_{n}\}_{n\geq 0} $ be the sequence of Padovan numbers defined by $ P_0=0 $, $ P_1 = P_2=1$, and $ P_{n+3}= P_{n+1} +P_n$ for all $ n\geq 0 $. In this paper, we find all positive square-free integers $ d $ such that the Pell equations $ x^2-dy^2 = \pm 1 $, $ X^2-dY^2=\pm 4 $ have at least two positive integer solutions $ (x,y) $ and $(x^{\prime}, y^{\prime})$, $ (X,Y) $ and $(X^{\prime}, Y^{\prime})$, respectively, such that each of $ x, ~x^{\prime}, ~X, ~X^{\prime} $ is a sum of two Padovan numbers.
First-Pass Metabolism of Polyphenols from Selected Berries: A High-Throughput Bioanalytical Approach
Authors: Olivas-Aguirre Francisco J. , Mendoza Sandra , Alvarez-Parrilla Emilio , Gonzalez-Aguilar Gustavo A. , Villegas-Ochoa Monica A. , Quintero-Vargas Jael T.J. , Wall-Medrano Abraham
Published: April 2020

Small berries are rich in polyphenols whose first-pass metabolism may alter their ultimate physiological effects. The antioxidant capacity and polyphenol profile of three freeze-dried berries (blackberry, raspberry, Red Globe grape) were measured and their apparent permeability (Papp) and first-pass biotransformation were tracked with an ex vivo bioanalytical system [everted gut sac (rat) + three detection methods: spectrophotometry, HPLC-ESI-QTOF-MS, differential pulse voltammetry (DPV)]. Total polyphenol (ratio 0.07-0.14-1.0) and molecular diversity (anthocyanins > flavan-3-ols), antioxidant capacity (DPPH, FRAP), anodic current maxima and Papp (efflux> uptake) were in the following order: blackberry > raspberry > Red Globe grape. Epicatechin, pelargonidin & cyanin (all), callistephin (raspberry/blackberry), catechin (grape), cyanidin glycosides (blackberry) and their derived metabolites [quinic acid, epicatechin, cyanidin/malvidin glucosides, and chlorogenic/caffeic acids] were fruit-specific and concentration-dependent. Time-trend DPV kinetic data revealed concurrent epithelial permeability & biotransformation processes. Regular permeability and high-biotransformation of berry polyphenols suggest fruit-specific health effects apparently at the intestinal level.
Synthesis, Structures, Electrochemistry, and Catalytic Activity towards Cyclohexanol Oxidation of Mono-, Di-, and Polynuclear Iron(III) Complexes with 3-Amino-2-Pyrazinecarboxylate
Authors: Karmakar Anirban , M.D.R.S. Martins Luísa , Yahorava Yuliya , C. Guedes da Silva M. Fátima , J. L. Pombeiro Armando
Published: April 2020

The synthesis and characterization of a set of iron(III) complexes, viz. the mononuclear [Fe(L)3] (1) and [NHEt3][Fe(L)2(Cl)2] (2), the dinuclear methoxido-bridged [Fe(L)2(μ-OMe)]2.DMF.1.5MeOH (3), and the heteronuclear Fe(III)/Na(I) two-dimensional coordination polymer [Fe(N3)(μ-L)2(μ-O)1/2(Na)(μ-H2O)1/2]n (4), are reported. Reactions of 3-amino-2-pyrazinecarboxylic acid (HL) with iron(III) chloride under different reaction conditions were studied, and the obtained compounds were characterized by elemental analysis, Fourier Transform Infrared (FT-IR) spectroscopy, and X-ray single-crystal diffraction. Compound 1 is a neutral mononuclear complex, whereas 2 is mono-anionic with its charge being neutralized by triethylammonium cation. Compounds 3 and 4 display a di-methoxido-bridged dinuclear complex and a two-dimensional heterometallic Fe(III)/Na(I) polynuclear coordination polymer, respectively. Compounds 3 and 4 are the first examples of methoxido- and oxido-bridged iron(III) complexes, respectively, with 3-amino-2-pyrazinecarboxylate ligands. The electrochemical study of these compounds reveals a facile single-electron reversible Fe(III)-to-Fe(II) reduction at a positive potential of 0.08V vs. saturated calomel electrode (SCE), which is in line with their ability to act as efficient oxidants and heterogeneous catalysts for the solvent-free microwave-assisted peroxidative oxidation (with tert-butyl hydroperoxide) of cyclohexanol to cyclohexanone (almost quantitative yields after 1 h). Moreover, the catalysts are easily recovered and reused for five consecutive cycles, maintaining a high activity and selectivity.
A Displacement Measuring Interferometer Based on a Frequency-Locked Laser Diode with High Modulation Frequency
Authors: Vu Thanh Tung , Hoang Hong Hai , Vu Toan Thang , Bui Ngoc Tam
Published: April 2020

Laser interferometers can achieve a nanometer-order uncertainty of measurements when their frequencies are locked to the reference frequencies of the atom or molecule transitions. There are three types of displacement-measuring interferometers: homodyne, heterodyne, and frequency modulation (FM) interferometers. Among these types of interferometer, the FM interferometer has many advantageous features. The interference signal is a series of time-dependent harmonics of modulation frequency, so the phase shift can be detected accurately using the synchronous detection method. Moreover, the FM interferometer is the most suitable for combination with a frequency-locked laser because both require frequency modulation. In previous research, low modulation frequencies at some tens of kHz have been used to lock the frequency of laser diodes (LDs). The low modulation frequency for the laser source means that the maximum measurement speed of the FM interferometers is limited. This paper proposes a novel contribution regarding the application of a high-frequency modulation for an LD to improve both the frequency stability of the laser source and the measurement speed of the FM interferometer. The frequency of the LD was locked to an I2 hyperfine component at 1 MHz modulation frequency. A high bandwidth lock-in amplifier was utilized to detect the saturated absorption signals of the I2 hyperfine structure and induce the signal to lock the frequency of the LD. The locked LD was then used for an FM displacement measuring interferometer. Moreover, a suitable modulation amplitude that affected the signal-to-noise ratio of both the I2 absorption signal and the harmonic intensity of the interference signal was determined. In order to verify the measurement resolution of the proposed interferometer, the displacement induced by a piezo electric actuator was concurrently measured by the interferometer and a capacitive sensor. The difference of the displacement results was less than 20 nm. To evaluate the measurement speed, the interferometer was used to measure the axial error of a high-speed spindle at 500 rpm. The main conclusion of this study is that a stable displacement interferometer with high accuracy and a high measurement speed can be achieved using an LD frequency locked to an I2 hyperfine transition at a high modulation frequency.
Methods for the Calculation of the Lost Profit in Construction Contracts
Authors: Majer Radovan , Ellingerová Helena , Gašparík Jozef
Published: April 2020

The aim of each investor is to procure the construction work in an efficient and economical way. This goal can be achieved by managing costs from the beginning of the investment process. It is necessary to determine the estimated price of the construction work in all phases of the investment process and not to underestimate the importance of this activity. It is almost a rule that the contractor or investor does not allow sufficient time for the contractor to prepare the construction for good quality, which may lead to insufficient preparation. The consequences of poor construction preparation vary from poorly built construction to litigation over the lost profits of the contractor—and this is the topic we discuss in this paper. The issue of asserting lost profits on the contract by the contractor is the subject of legal disputes between the contractor and the customer of construction work. In such cases, the question becomes the design of a methodology suitable for its calculation. The article deals with the presentation of the existing methods of loss of profit calculation, two of which are applied to the example of litigation from construction practice, with the definition of their results and differences.
Clinical Relevance of Liquid Biopsy in Melanoma and Merkel Cell Carcinoma
Authors: Boyer Magali , Cayrefourcq Laure , Dereure Olivier , Meunier Laurent , Becquart Ondine , Alix-Panabières Catherine
Published: April 2020

Melanoma and Merkel cell carcinoma are two aggressive skin malignancies with high disease-related mortality and increasing incidence rates. Currently, invasive tumor tissue biopsy is the gold standard for their diagnosis, and no reliable easily accessible biomarker is available to monitor patients with melanoma or Merkel cell carcinoma during the disease course. In these last years, liquid biopsy has emerged as a candidate approach to overcome this limit and to identify biomarkers for early cancer diagnosis, prognosis, therapeutic response prediction, and patient follow-up. Liquid biopsy is a blood-based non-invasive procedure that allows the sequential analysis of circulating tumor cells, circulating cell-free and tumor DNA, and extracellular vesicles. These innovative biosources show similar features as the primary tumor from where they originated and represent an alternative to invasive solid tumor biopsy. In this review, the biology and technical challenges linked to the detection and analysis of the different circulating candidate biomarkers for melanoma and Merkel cell carcinoma are discussed as well as their clinical relevance.
SOX2 Expression and Transcriptional Activity Identifies a Subpopulation of Cancer Stem Cells in Sarcoma with Prognostic Implications
Authors: Menendez Sofia T. , Rey Veronica , Martinez-Cruzado Lucia , Gonzalez M. Victoria , Morales-Molina Alvaro , Santos Laura , Blanco Verónica , Alvarez Carlos , Estupiñan Oscar , Allonca Eva , Rodrigo Juan Pablo , García-Castro Javier , Garcia-Pedrero Juana Maria , Rodriguez Rene
Published: April 2020

Stemness in sarcomas is coordinated by the expression of pluripotency factors, like SOX2, in cancer stem cells (CSC). The role of SOX2 in tumor initiation and progression has been well characterized in osteosarcoma. However, the pro-tumorigenic features of SOX2 have been scarcely investigated in other sarcoma subtypes. Here, we show that SOX2 depletion dramatically reduced the ability of undifferentiated pleomorphic sarcoma (UPS) cells to form tumorspheres and to initiate tumor growth. Conversely, SOX2 overexpression resulted in increased in vivo tumorigenicity. Moreover, using a reporter system (SORE6) which allows to monitor viable cells expressing SOX2 and/or OCT4, we found that SORE6+ cells were significantly more tumorigenic than the SORE6- subpopulation. In agreement with this findings, SOX2 expression in sarcoma patients was associated to tumor grade, differentiation, invasive potential and lower patient survival. Finally, we studied the effect of a panel of anti-tumor drugs on the SORE6+ cells of the UPS model and patient-derived chondrosarcoma lines. We found that the mithramycin analogue EC-8042 was the most efficient in reducing SORE6+ cells in vitro and in vivo. Overall, this study demonstrates that SOX2 is a pro-tumorigenic factor with prognostic potential in sarcoma. Moreover, SORE6 transcriptional activity is a bona fide CSC marker in sarcoma and constitutes an excellent biomarker for evaluating the efficacy of anti-tumor treatments on CSC subpopulations.
Student Participation in Online Content-Related Discussion and Its Relation to Students’ Background Knowledge
Authors: Turkkila Miikka , Lommi Henri
Published: April 2020

This paper presents two novel network methods developed for education research. These methods were used to investigate online discussions and the structure of students’ background knowledge in a blended university course for pre-service teachers (n = 11). Consequently, these measures were used for correlation analysis. The social network analysis of the online discussions was based on network roles defined using triadic motifs instead of more commonly used centrality measures. The network analysis of the background knowledge is based on the Katz centrality measure and Jaccard similarity. The results reveal that both measures have characteristic features that are typical for each student. These features, however, are not correlated when student participation is controlled for. The results show that the structure and extension of a student’s background knowledge does not explain their activity and role in online discussions. The limitations and implications of the developed methods and results are discussed.
Influence of Fluctuations in Fossil Fuel Commodities on Electricity Markets: Evidence from Spot and Futures Markets in Europe
Authors: Liu Tiantian , He Xie , Nakajima Tadahiro , Hamori Shigeyuki
Published: April 2020

Using a fresh empirical approach to time-frequency domain frameworks, this study analyzes the return and volatility spillovers from fossil fuel markets (coal, natural gas, and crude oil) to electricity spot and futures markets in Europe. In the time domain, by an approach developed by Diebold and Yilmaz (2012) which can analyze the directional spillover effect across different markets, we find natural gas has the highest return spillover effect on electricity markets followed by coal and oil. We also find that return spillovers increase with the length of the delivery period of electricity futures. In the frequency domain, using the methodology proposed by Barunik and Krehlik (2018) that can decompose the spillover effect into different frequency bands, we find most of the return spillovers from fossil fuels to electricity are produced in the short term while most of the volatility spillovers are generated in the long term. Additionally, dynamic return spillovers have patterns corresponding to the use of natural gas for electricity generation, while volatility spillovers are sensitive to extreme financial events.
Effects of Evaporator and Condenser in the Analysis of Adsorption Chillers
Authors: Lee Woo Su , Park Moon Yong , Duong Xuan Quang , Cao Ngoc Vi , Chung Jae Dong
Published: April 2020

In a survey of the literature from the last 20 years, 20% of the numerical models used to analyze the performance of adsorption chillers assumed the evaporator and condenser were ideal, with a fixed evaporation temperature and condenser temperature, and ignored interactions between the adsorption bed and evaporator/condenser. Even when the interaction with the evaporator and condenser was included, the other 80% of studies modeled the adsorption bed based on the LPM (lumped parameter method), which ignores the geometry effect and contact resistance of the bed, and thus reduces the accuracy of the analysis. As a consequence, these earlier numerical studies overestimated the system performance of the adsorption chiller. In this study, we conducted a refined numerical approach which avoids these limitations, producing estimates in close agreement with experimental results. Compared with our approach, the models with ideal treatment of evaporator and condenser overestimated COP (coefficient of performance) and SCP (specific cooling power) by as much as 16.12% and 24.64%, respectively. The models based on LPM overestimated COP and SCP by 22.82% and 11.28%, compared to our approach.
Rheology Methods as a Tool to Study the Impact of Whey Powder on the Dough and Breadmaking Performance of Wheat Flour
Authors: Macedo Christine , Nunes Maria Cristiana , Sousa Isabel , Raymundo Anabela
Published: April 2020

Considering the nutritional value, whey is an excellent ingredient for the development of food products, in line with the concept of a circular economy for the reuse of industry by-products. The main objective of this work was to evaluate the impact of the whey addition on the rheology of wheat flour dough and breadmaking performance, using both empirical and fundamental methods. Different levels of commercial whey powder (0%, 12%, 16% and 20% w/w) were tested in a bread formulation previously optimized. Dough mixing tests were performed using Micro-doughLab and Consistograph equipment, to determine the water absorptions of different formulations and evaluate empirical rheology parameters related to mixing tolerances. Biaxial extension was applied by the Alveograph to simulate fermentation during the baking process. Fermented doughs were characterized in a Texturometer using penetration and extensibility tests, and by small amplitude oscillatory shear (SAOS) measurements, a fundamental rheology method, in a Rheometer applying frequency sweeps. Loaf volume and firmness were used to study the breadmaking quality. Despite a negative impact on the empirical rheology parameters of the dough and poorer baking results, the use of this by-product should be considered for nutritional and sustainability reasons. In addition, significant correlations (r2 > 0.60) between the dough rheology parameters obtained from the empirical measurements were established. Changes in the gluten structure were not accurately detected by the SAOS measurements and Texture Profile Analysis of the doughs, and a correlation between fundamental and empirical measurements was not found. Consistograph or Micro-doughLab devices can be used to estimate bread firmness. Extensional tests in the Texturometer, using SMS/Kieffer Dough and Gluten Extensibility Rig, may predict loaf volume.
Lemon Juice, Sesame Paste, and Autoclaving Influence Iron Bioavailability of Hummus: Assessment by an In Vitro Digestion/Caco-2 Cell Model
Authors: Doumani Nour , Severin Isabelle , Dahbi Laurence , Bou-Maroun Elias , Tueni Maya , Sok Nicolas , Chagnon Marie-Christine , Maalouly Jacqueline , Cayot Philippe
Published: April 2020

Hummus, an iron-containing plant-based dish mainly made from chickpea purée, tahini, lemon juice and garlic, could be a valuable source of iron when bioavailable. Since the processing and formulation of food influence iron bioavailability, the present study investigated for the first time, their effects on hummus. Firstly, iron bioaccessibility was assessed on eight samples (prepared according to the screening Hadamard matrix) by in vitro digestion preceding iron dialysis. Then, iron bioavailability of four selected samples was estimated by the in vitro digestion/Caco-2 cell model. Total and dialyzable iron were determined by the atomic absorption spectrometry and ferritin formation was determined using an ELISA kit. Only autoclaving, among other processes, had a significant effect on iron bioaccessibility (+9.5, p < 0.05). Lemon juice had the highest positive effect (+15.9, p < 0.05). Consequently, the effect of its acidic components were investigated based on a full factorial 23 experimental design; no significant difference was detected. Garlic’s effect was not significant, but tahini’s effect was negative (−8.9, p < 0.05). Despite the latter, hummus had a higher iron bioavailability than only cooked chickpeas (30.4 and 7.23 ng ferritin/mg protein, respectively). In conclusion, hummus may be a promising source of iron; further in vivo studies are needed for confirmation.
Corn-Starch-Based Materials Incorporated with Cinnamon Oil Emulsion: Physico-Chemical Characterization and Biological Activity
Authors: Díaz-Galindo Edaena Pamela , Nesic Aleksandra , Bautista-Baños Silvia , Dublan García Octavio , Cabrera-Barjas Gustavo
Published: April 2020

Active packaging represents a large and diverse group of materials, with its main role being to prolong the shelf-life of food products. In this work, active biomaterials based on thermoplastic starch-containing cinnamon oil emulsions were prepared by the compression molding technique. The thermal, mechanical, and antifungal properties of obtained materials were evaluated. The results showed that the encapsulation of cinnamon oil emulsions did not influence the thermal stability of materials. Mechanical resistance to break was reduced by 27.4%, while elongation at break was increased by 44.0% by the addition of cinnamon oil emulsion. Moreover, the novel material provided a decrease in the growth rate of Botrytis cinerea by 66%, suggesting potential application in food packaging as an active biomaterial layer to hinder further contamination of fruits during the storage and transport period.
Fat Inclusion Level, NaCl Content and LAB Starter Cultures in the Manufacturing of Italian-Type Ostrich Salami: Weight Loss and Nutritional Traits
Authors: Cullere Marco , Novelli Enrico , Dalle Zotte Antonella
Published: April 2020

The experiment studied the effect of two different fat inclusion levels (30% and 40%), NaCl contents (2.4 and 2.6%) and starter cultures (lactic acid bacteria (LAB) 6: L. curvatus/S. xylosus; LAB 8: L. sakei/S. xylosus) on the weight loss and nutritional composition of Italian-type ostrich salami. With this purpose, 8 batches of 9 salami each (n = 72) were prepared. Salami were ripened for 20 weeks: weight loss was monitored throughout the experiment, while salami nutritional composition was evaluated at 10 and 20 weeks of ripening. The lowest fat and highest salt inclusion levels provided the highest cumulative weight loss throughout the trial. At 10 weeks of ripening, salami with 40% fat were the richest in moisture and fat, whereas the leanest ones had the highest protein, ash and cholesterol contents. LAB 6 provided salami with the highest moisture and protein, while LAB 8 increased fat and cholesterol contents. At 20 weeks of ripening the proximate composition of ostrich salami was solely affected by fat inclusion level, with similar findings to those observed at 10 weeks. Overall, fat inclusion level had a great impact on the weight loss and nutritional composition of Italian-style ostrich salami. Reducing the NaCl inclusion from 2.6% to 2.4%, the weight loss of ostrich salami was retarded by approximately 1 week, without affecting the nutritional composition of the final product. Results of the study suggested that it is feasible to produce salami with lower fat and salt contents, while ensuring satisfactory product quality.
Is Site-Specific Pasta a Prospective Asset for a Short Supply Chain?
Authors: Pasini Gabriella , Visioli Giovanna , Morari Francesco
Published: April 2020

In the 2011–2012 season, variable-rate nitrogen (N) fertilization was applied two times during durum wheat vegetative growth in three field areas which differed in soil fertility in northern Italy. The quality traits of the mono-varietal pasta obtained from each management zone were assessed in view of site-specific pasta production for a short supply chain. To this purpose, semolina from cv. Biensur obtained from management zones with different fertility treated with N at variable rate was tested in comparison with a commercial reference (cv. Aureo) to produce short-cut pasta. Biensur semolina demonstrated to have technological characteristics positively correlated with the low-fertility zones treated with high N doses (200 and 200+15 kg/ha) and, to a lesser extent, with the high-soil-fertility zones (130 and 130 + 15 kg/ha of N). The lower quality parameters were obtained for pasta produced with wheat from medium-fertility zones, independently of the N dose applied. The derived pasta obtained from the low-fertility zones treated with high N doses had cooking and sensory properties comparable to those of pasta obtained using the reference cv. Aureo. These results are explained by the higher amounts of gluten proteins and by a higher glutenin/gliadin ratio in semolina, which are indicators of technological quality. Overall, the results indicate that segregation of the grain at harvest led to the production of semolina with higher protein content and, hence, to a higher pasta quality. Therefore, site-specific pasta could be a potential asset for a short supply chain, aiming to improve traceability and environmental and economic sustainability.
Influence of Electrostatic Field on the Quality Attributes and Volatile Flavor Compounds of Dry-Cured Beef during Chill Storage
Authors: Xu Chen-Chen , Yu Hui , Xie Peng , Sun Bao-Zhong , Wang Xiang-Yuan , Zhang Song-Shan
Published: April 2020

The purpose was to investigate the quality characteristics of dry-cured beef with different storage times under a high-voltage electrostatic field (HVEF) condition. The pH, moisture content, meat color, and volatile compounds of dry-cured beef samples treated with HVEF (3 kV) were compared with those of a common refrigerator (CON) at days 0, 3, 7, 10, and 14. The results showed that, compared with CON group, the decline rates of the pH and moisture content of beef and ∆E values were lower under HVEF storage condition. From the fingerprints, the 42 volatile compounds identified were mainly aldehydes, alcohols, ketones, and esters. The benzaldehyde, trimethyl pyrazine, and maltol contents in the HVEF group exhibited a dramatic increase after 10 days of storage. Principal component analysis revealed clustering of compound classes, distributed in a separate time. Based on the above findings, we concluded that HVEF treatment could promote color stability and enhance characteristic flavor during the storage of dry-cured beef. These results suggested that HVEF might be applicable for dry-cured meat storage techniques.
Stability of the Meat Protein Type I Collagen: Influence of pH, Ionic Strength, and Phenolic Antioxidant
Authors: Lucarini Massimo , Durazzo Alessandra , Sciubba Fabio , Di Cocco Maria Enrica , Gianferri Raffaella , Alise Mosè , Santini Antonello , Delfini Maurizio , Lombardi-Boccia Ginevra
Published: April 2020

The water-holding capacity (WHC) is among the key factors in determining the quality of meat and its value, which is strongly influenced by the content and quality of the connective tissue proteins like collagen. Therefore, the factors that influence the proteins’ stability, e.g., pH, ionic strength, and the antioxidants which are used to increase the meat shelf-life, also affect the WHC. The interaction of collagen, whose structure is strongly influenced by the interaction with water molecules, can be studied following the behavior of water diffusion by low-resolution 1H NMR experiments. The present study is addressed to study the collagen stability as a function of pH, ionic strength, and phenolic antioxidants like catechin. The experimental study demonstrated how the 1H NMR time domain (TD) experiments are able to evaluate the hydration properties of collagen, not only as a function of ionic strength and pH, but also in determining the ability of catechin to interact both on the surface of the collagen fibrils and inside the fibrillar domain.
Determination of Drying Patterns of Radish Slabs under Different Drying Methods Using Hyperspectral Imaging Coupled with Multivariate Analysis
Authors: Lee Dongyoung , Lohumi Santosh , Cho Byoung-Kwan , Lee Seung Hyun , Jung Hyunmo
Published: April 2020

Drying kinetics and the moisture distribution map of radish slabs under different drying methods (hot-air drying (HAD), microwave drying (MD), and hot-air and microwave combination drying (HMCD)) were determined and visualized by hyperspectral image (HSI) processing coupled with a partial least square regression (PLSR)-variable importance in projection (VIP) model, respectively. Page model was the most suitable in describing the experimental moisture loss data of radish slabs regardless of the drying method. Dielectric properties (DP, ε ) of radish slices decreased with the decrease in moisture content (MC) during MD, and the penetration depth of microwaves in radish was between 0.81 and 1.15 cm. The PLSR-VIP model developed with 38 optimal variables could result in the high prediction accuracies for both the calibration ( R c a l 2 = 0.967 and RMSEC = 4.32 % ) and validation ( R v a l 2 = 0.962 and RMSEC = 4.45 % ). In visualized drying patterns, the radish slabs dried by HAD had a higher moisture content at the center than at the edges; however, the samples dried by MD contained higher moisture content at the edges. The nearly uniform drying pattern of radish slabs under HMCD was observed in hyperspectral images. Drying uniformity of radish slabs could be improved by the combination drying method, which significantly reduces drying time.
Classification and Authentication of Paprika by UHPLC-HRMS Fingerprinting and Multivariate Calibration Methods (PCA and PLS-DA)
Authors: Barbosa Sergio , Saurina Javier , Puignou Lluís , Núñez Oscar
Published: April 2020

In this study, the feasibility of non-targeted UHPLC-HRMS fingerprints as chemical descriptors to address the classification and authentication of paprika samples was evaluated. Non-targeted UHPLC-HRMS fingerprints were obtained after a simple sample extraction method and C18 reversed-phase separation. Fingerprinting data based on signal intensities as a function of m/z values and retention times were registered in negative ion mode using a q-Orbitrap high-resolution mass analyzer, and the obtained non-targeted UHPLC-HRMS fingerprints subjected to unsupervised principal component analysis (PCA) and supervised partial least squares regression-discriminant analysis (PLS-DA) to study sample discrimination and classification. A total of 105 paprika samples produced in three different regions, La Vera PDO and Murcia PDO, in Spain, and the Czech Republic, and all of them composed of samples of at least two different taste varieties, were analyzed. Non-targeted UHPLC-HRMS fingerprints demonstrated to be excellent sample chemical descriptors to achieve the authentication of paprika production regions with 100% sample classification rates by PLS-DA. Besides, the obtained fingerprints were also able to perfectly discriminate among the different paprika taste varieties in all the studied cases, even in the case of the different La Vera PDO paprika tastes (sweet, bittersweet, and spicy) which are produced in a very small region.
Assessment of the Effect of Secondary Fixation on the Structure of Meat Products Prepared for Scanning Electron Microscopy
Authors: Běhalová Hana , Tremlová Bohuslava , Kalčáková Ludmila , Pospiech Matej , Dordevic Dani
Published: April 2020

The aim of the research was to verify the necessity of secondary fixation with osmium tetroxide in various types of meat products and evaluation of structural changes of products using different fixation procedures. The material for the study consisted of 11 types of meat products that were analyzed using a scanning electron microscope (SEM) with two different methods of chemical fixation. The first method included the usual processing of biological samples: glutaraldehyde primary fixation, the use of a buffer, secondary fixation by osmium tetroxide (OsO4), buffer, and dehydration using ethanol of increasing concentrations. The second method comprised the glutaraldehyde primary fixation and dehydration using the ethanol of increasing concentrations only. The results unambiguously suggest that the main difference between these methods is in fixation and visibility of fat. Our analysis principally suggests that fixation of the product with OsO4 allows the tracking of all components (fat droplets, muscle fibers, connective tissue) in meat products. At the same time, our results also support the possibility that the secondary fixation can be skipped during the analysis, where the main objection is an observation of lipid-free structures of the meat products (e.g., connection between muscle and starches or spices) or meat products with an insignificant amount of fat.
Geographical Origin Authentication of Agri-Food Products: A Review
Authors: Katerinopoulou Katerina , Kontogeorgos Achilleas , Salmas Constantinos E. , Patakas Angelos , Ladavos Athanasios
Published: April 2020

This study is a systematic literature review of geographical origin authentication by elemental analytical techniques. Authentication and certification of geographic origin of agri-food products is a useful tool toward the protection of the quality for products. The aim of this work was to map the current state of research in the area of agricultural products and food, identifying emerging fields to the geographical origin of products. The article is divided in three parts. The first part of the article deals with the analytical techniques applied in the food authentication. Special mention is made to elemental analysis and multiple isotope ratio. The second section focuses on statistically published data concerning published research for geographical origin authentication for the period 2015–2019. Specific results are presented inter alia: number of articles according to the type of product, articles according to the type of the analytical techniques, and others. The third part contains characteristic results from articles that were published in the period 2015–2019, on certification of geographical origin on specific agricultural products.
A New Architecture of Densely Connected Convolutional Networks for Pan-Sharpening
Authors: Huang Wei , Feng Jingjing , Wang Hua , Sun Le
Published: April 2020

In this paper, we propose a new architecture of densely connected convolutional networks for pan-sharpening (DCCNP). Since the traditional convolution neural network (CNN) has difficulty handling the lack of a training sample set in the field of remote sensing image fusion, it easily leads to overfitting and the vanishing gradient problem. Therefore, we employed an effective two-dense-block architecture to solve these problems. Meanwhile, to reduce the network architecture complexity, the batch normalization (BN) layer was removed in the design architecture of DenseNet. A new architecture of DenseNet for pan-sharpening, called DCCNP, is proposed, which uses a bottleneck layer and compression factors to narrow the network and reduce the network parameters, effectively suppressing overfitting. The experimental results show that the proposed method can yield a higher performance compared with other state-of-the-art pan-sharpening methods. The proposed method not only improves the spatial resolution of multi-spectral images, but also maintains the spectral information well.