bluuebunny/crossref_metadata_2025 huggingface dataset:
Aktivitas Antidiare Ekstrak Etanol Daun Suji (Dracaena Angustifolia Roxb)
Authors: Sukmawati Ika Kurnia , Sukandar Elin Yulinah , Kurniati Neng Fisheri
Published: February 2018

Penyakit diare masih menjadi masalah kesehatan terutama diberbagai Negara berkembang termasuk Indonesia. Secara tradisional masyarakat telah menggunakan daun Suji (Dracaena angustifoliaRoxb L.) untuk mengatasi berbagai gangguan pencernaan termasuk diare.Tujuan dari penelitian ini adalah untuk menguji aktivitas antidiare dan antibakteri ekstrak etanol daun suji. Ekstraksi dilakukan dengan metode refluks menggunakan pelarut etanol 96 %.Uji aktivitas antimikroba dilakukan secara invitro dengan menggunakan metode broth microdilution terhadap ekstrak. Mikroba uji yang digunakan adalah Escherichia coli, Shigella dysenteriae, Shigella flexneri, dan Salmonella typhi. Dilakukan uji antidiare pada hewan uji yang diinduksi minyak jarak. Sediaan uji diberikan satu jam sebelum induksi kemudian dilakukan pengamatan terhadap feses (frekuensi, konsistensi dan berat). Metode waktu lintas usus juga dilakukan pada percobaan ini dengan prinsip membandingkan usus yang dilalui marker dengan panjang usus seluruhnya. Dari pengujian antibakteri ekstrak daun suji mempunyai kemampuan penghambatan pada bakteri Shigella dysenteriae, Shigella flexneri, Eschericia coli, dan Salmonella typhi, dengan KHM berturut-turut  25000 µg/ml,  25000 µg/ml, 12500 µg/ml, dan > 25000 µg/ml. Dari hasil uji aktivitas antidiare daun suji kelompok dosis ekstrak yang mempunyai aktivitas dalam memproteksi diare oleh minyak jarak yaitu dosis 50 mg/kgbb, dosis ini dapat menurunkan frekuensi defekasi  berbeda bermakna disbanding kelompok kontrol (p<0,05) , dosis 25 mg/kgbb dan 100 mg/kgbb dapat meningkatkan konsistensi dan menurunkan berat feses.
Cost Effectiveness Analysis Therapy Combination of Candesartan-Amlodipine and Candesartan-Diltiazem on Hypertensive Outpatients
Authors: Baroroh Faridah , Sari Andriana
Published: February 2018

Hypertension medication is taken for a long period and thus requires considerable costs. As antihypertensives vary in efficacy, research is needed to assess the cost effectiveness of medication, particularly between candesartan-amlodipine and candesartan-diltiazem combinations on hypertensive outpatients. This study applied a prospective cohort design with outcome observations for three months at a private hospital in Yogyakarta. The outcome used to gauge the cost effectiveness of medication was the achievement of the targeted blood pressure reduction after treatment. The cost effectiveness analysis was conducted through payer’s perspective, namely that of the social security agency (BPJS), with direct medical cost as the cost component measured. Cost effectiveness was analyzed using an average cost effectiveness ratio (ACER), calculated according to the ratio of cost to the outcome percentage of the blood pressure reduction target attainment, and an incremental cost effectiveness ratio (ICER) based on the ratio between differences in cost and outcome in both medication groups. The research subjects consisted of 33 patients, 24 of whom underwent medication with candesartan-amlodipine combination and 9 with candesartan-diltiazem. As many as 81.82% were female and 72.73% were within the age range of 51-70, while their most frequent complication was diabetes mellitus (48.48%). Results revealed the effectiveness of candesartan-amlodipine medication to be 58.33% with an ACER value of IDR 6,617, whereas that of candesartan-diltiazem was 22.22% with an ACER of IDR 29,733. The ICER value was IDR -7607, indicating that candesartan-amlodipine was categorically more cost-effective than candesartan-diltiazem.
The directive speech acts used in english speaking class
Authors: Bayanuddin Muhammad Khatib , Jamaluddin Jamaluddin , Suryani Hilma
Published: February 2018

This research discusses about an analysis of the directive speech acts used in english speaking class at the third semester of english speaking class of english study program of IAIN STS Jambi. The aims of this research are to describe the types of directive speech acts and politeness strategies that found in English speaking class. This research used descriptive qualitative method. This method used to describe clearly about the types and politeness strategies of directive speech acts based on the data in English speaking class. The result showed that in English speaking class that there are some types and politeness strategies of directive speech acts, such as: requestives, questions, requirements, prohibitives, permissives, and advisores as types, as well as on-record indirect strategies (prediction statement, strong obligation statement, possibility statement, weaker obligation statement, volitional statement), direct strategies (imperative, performative), and nonsentential strategies as politeness strategies. The achievement of this research are hoped can be additional knowledge about linguistics study, especially in directive speech acts and can be developed for future researches.

Key words: directive speech acts, types, politeness strategies.
Students’ anxieties in speaking class
Authors: Rahman Mahyuzar
Published: February 2018

This qualitative research discussed the anxieties the students of semester 3, English Department, IAIN STS Jambi faced during the speaking class. The result of the research indicated that the causes of the students’ anxieties were the lack of grammar mastery, pronunciation problem, lack of vocabulary, unconfident feeling, fear of making mistakes and feared of being laughed by other students. But the dominant factors found were the lack of grammar, the lack of good pronunciation, and lack of vocabulary mastery. The lecturer had taken part to overcome these problems by giving them motivation not to give up easily, how to cope with vocabulary problems, and how to prepare well before coming into the class.
Pengembangan media pembelajaran berbasis macromedia flash professional 8
Authors: Syefrinando Boby
Published: February 2018

Tujuan dari penelitian ini adalah untuk mengembangkan media pembelajaran berbasis pada Macromedia Flash Proffesional 8, khususnya dalam pembelararan fisika. Penelitian ini menggunakan desain penelitian dan pengembangan (research and development) yang mencakup langkah utama dalam penerapannya yaitu pendahuluan, perancangan media, danevaluasi. Penelitian ini menemukan bahwa ada tujuh langkah dalam merancang media pembelajaran yaitu; analisis kebutuhan dan karakter siswa, perumusan tujuan pembelajaran, validasi dan revisi berdasarkan penilaian ahli, uji coba, dan revisi akhir. Hasil penelitian juga menunjukkan bahwa media pembelajaran berbasis Macromedia Flash Proffesional 8 efektif digunakan sebagai media dalam pengajaran fisika, khususnya pada pokok bahasan Hukum Newton.

Kata Kunci : Media pembelajaran, Macromedia Flash Proffesional 8, mata kuliah Fisika

Abstract

[Devepoling Macromedia Flash Proffesional 8 Based Teaching Media]. The purpose of the study was to develop teaching media based on Macromedia Flash Proffesional 8, particuraly for physics course. This Study employed research and development (R&D) design, including three major steps, there are; preliminary, designing media, and evaluating. The study showed that there are sevent steps in designing teaching media, including; need analysis and students character, formulating learning objectives, validating and revising based on expert judgment, trials, and revision. The result of the study also indicated that Macromedia Flash Proffesional 8 based teaching media was effective to used in teaching Newton’s Law subject in physics course

Keywords: Teaching media, Macromedia Flash Proffesional 8, physics course
Pendidikan dalam Pandangan Masyarakat Baduy Dalam
Authors: Asyari Hasyim , Syaripullah Syaripullah , Irawan Rudini
Published: February 2018

Abstrak
Penelitian ini bertujuan untuk mendeskripsikan pendidikan dalam pandangan masyarakat Baduy Dalam. Metode yang digunakan dalam penelitian ini adalah penelitian kualitatif dan dianalisa dengan pendekatan etnografi. Hasil penelitian ini mengungkapkan beberapa hal penting: pertama, masyarakat Baduy Dalam berpandangan bahwa pendidikan dasar mereka terbatas pada pengetahuan adat yang meliputi materi pembelajaran bidang pertanian, nilai-nilai kebudayaan, aturan tatanan hukum adat, dan keterampilan. Kedua, model atau bentuk pendidikannya dilakukan dengan cara lisan dan praktik langsung, yang diwariskan secara turun-temurun melalui keluarga, lembaga adat, maupun teman sebaya. Ketiga, masyarakat Baduy Dalam sampai saat ini tetap menolak segala macam bentuk pendidikan yang tidak sesuai dengan tataran hukum adat. Keempat, terdapat perubahan kehidupan sosial masyarakat Baduy Dalam yang disebabkan semakin banyaknya kontak langsung dengan pengunjung meskipun tidak bersifat masif.
Keywords: Baduy Dalam, Adat, Model Pendidikan

Abstract
[Education in the View of Baduy Society ] This study aims to describe education in view of Baduy Dalam society. The method used in this research is qualitative research, and analyzed with ethnography approach. The results of this study reveal several important points: first, the Baduy Dalam community holds that their basic education that limited to indigenous knowledge, learning materials implementation of education that of agriculture, cultural values, rules of customary law, and skills. Second, the model or form education by way of verbal communication and direct practice, who passed down through generations through family, traditional institutions, and peers. Third, the Baduy Dalam community still rejects all forms of education that are not in accordance with the level of customary law. Fourth, the change of sosial life society Baduy Dalam caused by many direct contact with visitors despite not massive at all.
Keywords: Baduy Dalam, Custom, Educational Model
Think Pair and Share for Junior High School Students' Reading Comprehension
Authors: Nurbaya Siti , Fitria Wahyuni
Published: February 2018

Abstrak
The objectives of this study was to find out whether or not there was a significant effect of the using Think-Pair and Share technique at seventh grade students’ reading comprehension of Junior High School Satu Atap Bertam. This research was conducted at first grade students of Junior high school Satu Atap Bertam. This school is located in Muaro Jambi, there are two classes of seventh grade students, and this school uses school based curriculum. In conducting the research, the writer used the experimental research, and the design of the experimental research was a quasi-experimental research. The result of the research found two things: First, the writer has computed the two means score by using t -test formula; the value of t-test was higher than the value of t-table. It indicated that there was a different on the students’ reading comprehension that was taught by using Think Pair and Share technique. Second, the result of the analysis indicated there was a significant difference between the students’ reading comprehension taught by using Think Pair and Share technique and those who were not.
Keywords: Think-Pair and share technique; reading comprehension
The Male and Female Students' Language Performance In Ritelling Story
Authors: Safitri Suryani , Jamaluddin Jamaluddin , Tartila Tartila
Published: February 2018

Abstract
This research discusses about an analysis of male and female students’ English performance in retelling story at eleventh grade at Islamic boarding school An-Nur Jambi. The aim of this research is to describe the English performance shown by the eleventh grade students (male and female) as a reference for the English teachers to enhance the students’ English story telling ability for both male and female students. This research used descriptive qualitative method. This method was used to describe the problem under discussion thoroughly. The students language performance in this research was assessd based on speaking proficiency description checklist modified from Adam and Frith. The result showed that in all aspects of speaking performance in story telling such as pronunciation, grammar, vocabulary, fluency and comprehension towards the story, female students had higher score than male students.
Keywords: Language performance, retelling story, Islamic Boarding School
SISTEM PAKAR DIAGNOSA HAMA DAN PENYAKIT TANAMAN CABAI BESAR MENGGUNAKAN METODE CERTAINTY FACTOR
Authors: Sri Hariyati Fitriasih Tomi Winanto, Yustina Retno Wahyu Utami,
Published: February 2018

Chili plants have a lot of pest and disease attacks. Pest and disease attacks potentially reduce the production of chilli and even cause crop failure. In addition, the limited number of extension workers and the lack of knowledge of practitioners / chili farmers inhibits efforts to control pests and diseases of chili plants. Therefore, the authors propose an expert system to diagnose pests and diseases in large chili plants using the Certainty Factor method. The Certainty Factor method is used to perform calculations by providing an expert's level of confidence. Expert systems relate symptoms and diseases as well as pest and disease control solutions of large chili plants. The data were obtained based on interviews with experts at the Organization for Industrial, Spiritual and Cultural Advancement (OISCA) Training Center Karanganyar. The data obtained was analyzed and expert system design application was made using UML diagram. The design is continued with the implementation of expert system application into PHP programming and MySQL database. The test results show that the system can diagnose pests and diseases of large chili plants like an expert. Keyword: certainty factor, expert system, pest and disease, large chili plant (Capsicum Annuum Longum).
SISTEM PENDUKUNG KEPUTUSAN PEMILIHAN SISWA BERPRESTASI DI SMP NEGERI 1 POLOKARTO SUKOHARJO MENGGUNAKAN METODE WEIGHTED PRODUCT (WP)
Authors: Sri Hariyati Fitriasih Aqoid Mustofa Ardhi, Dwi Remawati ,
Published: February 2018

This research is to make decision support system from student selection achievement in SMP Negeri 1 Polokarto Sukoharjo which still done manually. The method used is weighted product. System design using UML. Testing this system aims to find the level of validity of the system that applies the weight of algorithm products with MS.excel calculation with the same criteria and the same weight on each alternative for the results of calculating the distance relative to the ideal solution manual. The result of this research is making decision support system from student achievement. Keywords: decision support system, student selection achievement, weighted product
RANCANGAN ALGORITMA GENERATOR MODEL 3D UNTUK MEMBUAT OBJEK BERUPA CABAI
Authors: Sukoco Omega Rimba Gemilang, M. Suyanto,
Published: February 2018

AbstractAlong later development of technology, 3D models are increasingly used almost in all circles and fields. With so a 3D model can be used as a medium of learning simulations and attractive arranged in such a way. Alongside the presence of 3D applications that can be used both free and proprietary, animators develop Karyana expected to support the learning of interest. The aim of this study as a learning medium and can be used as a computer program to create 3D models. In accordance with the proper sequence of steps, the process of making the object will be greatly facilitated. And supported by using a script program is expected to create objects in large quantities can be easily and vary in shape and size but they can be modified by the animator. Generator 3D model is a solution to create objects in large quantities. 3D models created as an instance is the object of the chili. Generator 3D model has been tested and is capable of forming a desired object. Keywords— Algorithm, Python, Modeling, 3D Models, Generator
SISTEM INFORMASI PENJUALAN KREDIT PADA MOHAN GROSIR SOLO SECARA MULTIUSER
Authors: Andriani Kusumaningrum Riwi Astuti, Bebas Widada,
Published: February 2018

Mohan Grosir Solo is a store engaged in the field of Sales and Sales Cooperation Sales with Credit Sales System. Sales of credit that runs from direct submission to the cashier by submitting identity cards only. Customers do the taking of goods in accordance with the value of the approved filing then the customer will pay in accordance with the applicable provisions. With the credit sales information system is expected small errors up to the large can be resolved, especially the problem of payment arrears and repayment payment. System design that includes: Diagram Context, HIPO, Data Flow Diagrams, Document Flow Diagrams, Database Design, Input Design, Output Design, Implementation of the program by using appropriate data stimulation. The purpose of this research is to create and design multi-level loan sales information system at Mohan Grosir Solo. Then the results obtained from this system are Input of Goods Data, Input of Customer Data, Input of Supplier Data, Input of Data of Department of Goods, Input of Cashier Data, Purchase Transaction, Purchase Return Transaction, Credit Sale Transaction, Sales Return Transaction, Cash Transaction, Customer Data Report, Supplier Data Report, Department of Goods Data Report, Cashier Data Report, Purchase Transaction Report, Purchase Return Report, Credit Sales Transaction Report, Sales Returns Report, and Cash Advance Report. System information created using Microsoft Visual Basic 6 and SQL Server database has been done blackbox testing with a design that is appropriate. Keywords: Information System, Multiuser, Credit Sales.
Küçük Luristan Atabeyliği'nde Kadın Bir Hükümdar: Devlet Hatun
Authors: KÜÇÜKBEKİR Esin
Published: February 2018

Küçük Luristan Atabeyliği (Lur-i Kuçek), XII. ile XVI. yüzyıllar arasında Hürremabad merkez olmak üzere Batı İran’da kurulmuştur. Hanedan, kurucusu ve ilk emiri Şucâüddin Hurşid’ten dolayı Hurşidiler olarak da bilinmektedir. Siyasi çekişmelerin yoğun olduğu dönemlerde Luristan Atabeyliği, Türkmenlerin ve Moğolların baskılarına ve saldırılarına maruz kalmıştır. Hanedanın yöneticilerinden İzzeddin Muhammed’in kendinden sonra tahtını bırakacağı oğlu veya kardeşi olmadığından o ölünce atabeyliğin başına eşi Devlet Hatun geçmiştir. Hanedanın ilk kadın hükümdarı olan ve bir müddet yöneticilik yapan Devlet Hatun Moğol baskılarının devam etmesi üzerine tahtı kardeşi İzzeddin Hüseyin’e bırakmak zorunda kalmıştır. Araştırmamızdaki amaç, Ortaçağ İranı’nda yer etmiş bu kadın hükümdarın siyasi faaliyetlerini kaynakların verdiği bilgiler ışığında açıklamaktır.
“Son et lumiere” en 35 mm.
Authors: Chort Jacques J.
Published: February 2018

Lors de la conférence du OMLTA à Toronto en avril 72, j’ai eu l’honneur et l’avantage de pouvoir présenter quelques films qui n’étaient alors que la réalisation d'un projet local amorce quelques mois plus tôt dans notre département. Il s’agissait en fait de deux projets bien distincts, visant au même but, celui d'apporter des solutions pratiques a des problèmes que beaucoup se plaisent à considérer comme étant purement pédagogiques ou linguistiques. Vous ne trouverez dans cet article que le résultat concert d'une recherche commune (certes, basée sur des principes de pédagogie bien établis) qui devrait apporter à chaque professeur de français “un peu d'eau a son moulin” dans son travail de tous les jours.
French Excursions in Ontario
Authors: Thompson Cecile
Published: February 2018

Teachers of French have traditionally taken their classes on visits to Paris, the Quebec Winter Carnival or on an exchange with a school in the province of Quebec. Groups normally have to be restricted in size and the cost may be prohibitive for a number of those students who might benefit most from the experience. Furthermore, as Boards of Education become more reluctant to authorize extended out-of-province excursions, specially for classes in elementary schools, one must explore and utilize local resource centres.
Visuals in the French Classroom
Authors: Boswell Allan
Published: February 2018

Are your students given enough variety in their French classes? Are they given enough freedom to learn French as a useful language? Can they describe the world they see about them? Are they given the opportunity to write or talk on a topic of their own choice?
Focus on Writing
Authors: Kerr Doris
Published: February 2018

Time and place seem to be the key factors in determining the status and function of writing in a second-language program for schools. Before the introduction of the new courses of study in Ontario in the mid-sixties, an observer of our French language programs in that province would have had good reason to assume that writing stood second only to reading on the scale of priorities allocated to the four language skills. Our materials, our lesson plans, our teaching methods and our external examinations seemed specifically designed to rate language skills in the following descending order of importance: reading, writing, speaking, listening.
More Grammar
Authors: McLean R. J.
Published: February 2018

Reprinted from The Bulletin, Vol. 53, No. 2, March 1973, pp. 105-106, published by The Ontario Secondary School Teachers’ Federation, with the permission of the author. For some time, students have been exposed to oral French programmes. How valid are they? Should we pause to assess the gap between theory and practice? Should our programmes be redirected? Let us find out from our students. Here are some
Conversion of a Direct to an Indirect Refrigeration System at Medium Temperature Using R-134a and R-507A: An Energy Impact Analysis
Authors: Llopis Rodrigo , Sánchez Daniel , Cabello Ramón , Catalán-Gil Jesús , Nebot-Andrés Laura
Published: February 2018

This work presents the experimental evaluation of energy consumption and refrigerant charge reduction when a commercial direct expansion refrigeration system is converted into an indirect system. The evaluation (with R-134a and R-507A) used a commercial cabinet with doors for medium temperature and a single-stage refrigeration cycle using a semi-hermetic compressor and electronic expansion valve; 24-h energy consumption tests were performed at laboratory conditions for each refrigerant and configuration at three heat rejection levels (23.3, 32.8 and 43.6 °C), maintaining an average product temperature inside the cabinet of 2 °C. The work analyses the impact of the conversion on temperature and pressure indicators, as well as, in the energy performance of each element. For R-134a the refrigerant charge was reduced in a 42.9%, but the energy consumption rose by 22.0%–22.8%; for R-507A the charge reduction was of 32.8% with an increase in energy consumption of between 27.7% and 38.7%.
Consequences of Lamin B1 and Lamin B Receptor Downregulation in Senescence
Authors: Lukášová Emilie , Kovařík Aleš , Kozubek Stanislav
Published: February 2018

Anchoring of heterochromatin to the nuclear envelope appears to be an important process ensuring the spatial organization of the chromatin structure and genome function in eukaryotic nuclei. Proteins of the inner nuclear membrane (INM) mediating these interactions are able to recognize lamina-associated heterochromatin domains (termed LAD) and simultaneously bind either lamin A/C or lamin B1. One of these proteins is the lamin B receptor (LBR) that binds lamin B1 and tethers heterochromatin to the INM in embryonic and undifferentiated cells. It is replaced by lamin A/C with specific lamin A/C binding proteins at the beginning of cell differentiation and in differentiated cells. Our functional experiments in cancer cell lines show that heterochromatin in cancer cells is tethered to the INM by LBR, which is downregulated together with lamin B1 at the onset of cell transition to senescence. The downregulation of these proteins in senescent cells leads to the detachment of centromeric repetitive sequences from INM, their relocation to the nucleoplasm, and distension. In cells, the expression of LBR and LB1 is highly coordinated as evidenced by the reduction of both proteins in LBR shRNA lines. The loss of the constitutive heterochromatin structure containing LADs results in changes in chromatin architecture and genome function and can be the reason for the permanent loss of cell proliferation in senescence.
Simulation and Optimization of Control of Selected Phases of Gyroplane Flight
Authors: Stalewski Wienczyslaw
Published: February 2018

Optimization methods are increasingly used to solve problems in aeronautical engineering. Typically, optimization methods are utilized in the design of an aircraft airframe or its structure. The presented study is focused on improvement of aircraft flight control procedures through numerical optimization. The optimization problems concern selected phases of flight of a light gyroplane—a rotorcraft using an unpowered rotor in autorotation to develop lift and an engine-powered propeller to provide thrust. An original methodology of computational simulation of rotorcraft flight was developed and implemented. In this approach the aircraft motion equations are solved step-by-step, simultaneously with the solution of the Unsteady Reynolds-Averaged Navier–Stokes equations, which is conducted to assess aerodynamic forces acting on the aircraft. As a numerical optimization method, the BFGS (Broyden–Fletcher–Goldfarb–Shanno) algorithm was adapted. The developed methodology was applied to optimize the flight control procedures in selected stages of gyroplane flight in direct proximity to the ground, where proper control of the aircraft is critical to ensure flight safety and performance. The results of conducted computational optimizations proved the qualitative correctness of the developed methodology. The research results can be helpful in the design of easy-to-control gyroplanes and also in the training of pilots for this type of rotorcraft.
‘Reparational’ Genetics: Genomic Data and the Case for Reparations in the Caribbean
Authors: Torres Jada
Published: February 2018

Drawing on my population genomic research among several Caribbean communities, I consider how ongoing Caribbean reparations movements index genomic information. Specifically, I examine the intersection between genetic ancestry and calls for reparatory justice to gain insight into the ways that scientific data are utilized in social articulations of both racial and indigenous identity. I argue that when contextualized within complex historical and cultural frameworks, the application of genomic data complicates notions about biological continuity and belonging, yet is compatible with broader conceptualizations of how people imagine themselves and histories in relation to geographic origins.
Chromosome Evolution in Marsupials
Authors: Deakin Janine
Published: February 2018

Marsupials typically possess very large, distinctive chromosomes that make them excellent subjects for cytogenetic analysis, and the high level of conservation makes it relatively easy to track chromosome evolution. There are two speciose marsupial families with contrasting rates of karyotypic evolution that could provide insight into the mechanisms driving genome reshuffling and speciation. The family Dasyuridae displays exceptional karyotype conservation with all karyotyped species possessing a 2n = 14 karyotype similar to that predicted for the ancestral marsupial. In contrast, the family Macropodidae has experienced a higher rate of genomic rearrangement and one genus of macropods, the rock-wallabies (Petrogale), has experienced extensive reshuffling. For at least some recently diverged Petrogale species, there is still gene flow despite hybrid fertility issues, making this species group an exceptional model for studying speciation. This review highlights the unique chromosome features of marsupial chromosomes, particularly for these two contrasting families, and the value that a combined cytogenetics, genomics, and epigenomics approach will have for testing models of genome evolution and speciation.
High-Entropy Alloys (HEAs)
Authors: Gao Michael , Qiao Junwei
Published: February 2018

High-entropy alloys (HEAs) [1,2] loosely refer to multi-principal-element solid solution alloys due to their high configurational entropy, in contrast to traditional alloys, which focus on the edge or corner of phase diagrams with one principal component[...]
Influence of Boron on the Creep Behavior and the Microstructure of Particle Reinforced Aluminum Matrix Composites
Authors: Siebeck Steve , Roder Kristina , Wagner Guntram , Nestler Daisy
Published: February 2018

The reinforcement of aluminum alloys with particles leads to the enhancement of their mechanical properties at room temperature. However, the creep behavior at elevated temperatures is often negatively influenced. This raises the question of how it is possible to influence the creep behavior of this type of material. Within this paper, selected creep and tensile tests demonstrate the beneficial effects of boron on the properties of precipitation-hardenable aluminum matrix composites (AMCs). The focus is on the underlying microstructure behind this effect. For this purpose, boron was added to AMCs by means of mechanical alloying. Comparatively higher boron contents than in steel are investigated in order to be able to record their influence on the microstructure including the formation of potential new phases as well as possible. While the newly formed phase Al3BC can be reliably detected by X-ray diffraction (XRD), it is difficult to obtain information about the phase distribution by means of scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM) investigations. An important contribution to this is finally provided by the investigation using Raman microscopy. Thus, the homogeneous distribution of finely scaled Al3BC particles is detectable, which allows conclusions about the microstructure/property relationship.
Study of Relation between Shot Peening Parameters and Fatigue Fracture Surface Character of an AW 7075 Aluminium Alloy
Authors: Trško Libor , Fintová Stanislava , Nový František , Bokůvka Otakar , Jambor Michal , Pastorek Filip , Florková Zuzana , Oravcová Monika
Published: February 2018

Shot peening is a well-known surface treatment method used for fatigue life improvement of cyclically loaded structural components. Since three main variables are considered in the peening process (peening intensity, coverage and peening media type), there is no direct way to choose the best combination of treatment parameters for the best performance, thus it has to be based on experience and laboratory tests. When shot peening is performed with inadequate parameters, or the peening process is not stable in time (decrease of the peening pressure, deterioration of the peening media and so on), it can result in significant degradation of the treated component fatigue properties, what is commonly called as the “overpeening” effect. When a premature fatigue fracture occurs in operation, the fracture surface analysis is usually the most important method of revealing the damage mechanism. This work is aimed at the study of the relation between the shot peening parameters and the fatigue fracture surface character on an AW 7075 aluminium alloy with an objective of identifying marks of overpeening and investigating the fatigue crack initiation mechanism. After performing the tests, it was observed that shot peening with optimized parameters creates a surface layer that is able to change the mechanism of the fatigue crack propagation and improve fatigue strength. On the other hand, using extensive peening parameters decrease the fatigue strength due to the creation of surface cracks and surface layer delamination.
Mexican Propolis: A Source of Antioxidants and Anti-Inflammatory Compounds, and Isolation of a Novel Chalcone and ε-Caprolactone Derivative
Authors: Guzmán-Gutiérrez Silvia , Nieto-Camacho Antonio , Castillo-Arellano Jorge , Huerta-Salazar Elizabeth , Hernández-Pasteur Griselda , Silva-Miranda Mayra , Argüello-Nájera Omar , Sepúlveda-Robles Omar , Espitia Clara , Reyes-Chilpa Ricardo
Published: February 2018

The propolis produced by bees are used in alternative medicine for treating inflammation, and infections, presumably due to its antioxidant properties. In this context, five propolis from México were investigated to determine their inhibitory lipid peroxidation properties. The ethyl acetate extract from a red propolis from Chiapas State (4-EAEP) was the most potent (IC50 = 1.42 ± 0.07 μg/mL) in the TBARS assay, and selected for further studies. This extract afforded two new compounds, epoxypinocembrin chalcone (6), and an ε-caprolactone derivative (10), as well as pinostrobin (1), izalpinin (2), cinnamic acid (3), pinocembrin (4), kaempherol (5), 3,3-dimethylallyl caffeate in mixture with isopent-3-enyl caffeate (7a + 7b), 3,4-dimethoxycinnamic acid (8), rhamnetin (9) and caffeic acid (11). The HPLC profile, anti-mycobacterial, and antioxidant properties of this extract was also determined. Most of the isolated compounds were also tested by inhibition of reactive oxygen species (ROS) in challenged mouse bone marrow-derived mast cells (BMMCs), and DPPH. Their anti-inflammatory activity was evaluated by TPA, and MPO (myeloperoxidase) activity by ear edema test in mice. The most potent compounds were 7a + 7b in the TBARS assay (IC50 = 0.49 ± 0.06 μM), and 2 which restored the ROS baseline (3.5 μM). Our results indicate that 4-EAEP has anti-oxidant, and anti-inflammatory properties due to its active compounds, suggesting it has anti-allergy and anti-asthma potential.
Interplay between P-Glycoprotein Expression and Resistance to Endoplasmic Reticulum Stressors
Authors: Hano Milan , Tomášová Lenka , Šereš Mário , Pavlíková Lucia , Breier Albert , Sulová Zdena
Published: February 2018

Multidrug resistance (MDR) is a phenotype of cancer cells with reduced sensitivity to a wide range of unrelated drugs. P-glycoprotein (P-gp)—a drug efflux pump (ABCB1 member of the ABC transporter gene family)—is frequently observed to be a molecular cause of MDR. The drug-efflux activity of P-gp is considered as the underlying mechanism of drug resistance against P-gp substrates and results in failure of cancer chemotherapy. Several pathological impulses such as shortages of oxygen and glucose supply, alterations of calcium storage mechanisms and/or processes of protein N-glycosylation in the endoplasmic reticulum (ER) leads to ER stress (ERS), characterized by elevation of unfolded protein cell content and activation of the unfolded protein response (UPR). UPR is responsible for modification of protein folding pathways, removal of misfolded proteins by ER associated protein degradation (ERAD) and inhibition of proteosynthesis. However, sustained ERS may result in UPR-mediated cell death. Neoplastic cells could escape from the death pathway induced by ERS by switching UPR into pro survival mechanisms instead of apoptosis. Here, we aimed to present state of the art information about consequences of P-gp expression on mechanisms associated with ERS development and regulation of the ERAD system, particularly focused on advances in ERS-associated therapy of drug resistant malignancies.
Design, Synthesis and in Combo Antidiabetic Bioevaluation of Multitarget Phenylpropanoic Acids
Authors: Colín-Lozano Blanca , Estrada-Soto Samuel , Chávez-Silva Fabiola , Gutiérrez-Hernández Abraham , Cerón-Romero Litzia , Giacoman-Martínez Abraham , Almanza-Pérez Julio , Hernández-Núñez Emanuel , Wang Zhilong , Xie Xin , Cappiello Mario , Balestri Francesco , Mura Umberto , Navarrete-Vazquez Gabriel
Published: February 2018

We have synthesized a small series of five 3-[4-arylmethoxy)phenyl]propanoic acids employing an easy and short synthetic pathway. The compounds were tested in vitro against a set of four protein targets identified as key elements in diabetes: G protein-coupled receptor 40 (GPR40), aldose reductase (AKR1B1), peroxisome proliferator-activated receptor gama (PPARγ) and solute carrier family 2 (facilitated glucose transporter), member 4 (GLUT-4). Compound 1 displayed an EC50 value of 0.075 μM against GPR40 and was an AKR1B1 inhibitor, showing IC50 = 7.4 μM. Compounds 2 and 3 act as slightly AKR1B1 inhibitors, potent GPR40 agonists and showed an increase of 2 to 4-times in the mRNA expression of PPARγ, as well as the GLUT-4 levels. Docking studies were conducted in order to explain the polypharmacological mode of action and the interaction binding mode of the most active molecules on these targets, showing several coincidences with co-crystal ligands. Compounds 1–3 were tested in vivo at an explorative 100 mg/kg dose, being 2 and 3 orally actives, reducing glucose levels in a non-insulin-dependent diabetes mice model. Compounds 2 and 3 displayed robust in vitro potency and in vivo efficacy, and could be considered as promising multitarget antidiabetic candidates. This is the first report of a single molecule with these four polypharmacological target action.
Modification and Assembly of a Versatile Lactonase for Bacterial Quorum Quenching
Authors: Rhoads Melissa , Hauk Pricila , Gupta Valerie , Bookstaver Michelle , Stephens Kristina , Payne Gregory , Bentley William
Published: February 2018

This work sets out to provide a self-assembled biopolymer capsule activated with a multi-functional enzyme for localized delivery. This enzyme, SsoPox, which is a lactonase and phosphotriesterase, provides a means of interrupting bacterial communication pathways that have been shown to mediate pathogenicity. Here we demonstrate the capability to express, purify and attach SsoPox to the natural biopolymer chitosan, preserving its activity to “neutralize” long-chain autoinducer-1 (AI-1) communication molecules. Attachment is shown via non-specific binding and by engineering tyrosine and glutamine affinity ‘tags’ at the C-terminus for covalent linkage. Subsequent degradation of AI-1, in this case N-(3-oxododecanoyl)-l-homoserine lactone (OdDHL), serves to “quench” bacterial quorum sensing (QS), silencing intraspecies communication. By attaching enzymes to pH-responsive chitosan that, in turn, can be assembled into various forms, we demonstrate device-based flexibility for enzyme delivery. Specifically, we have assembled quorum-quenching capsules consisting of an alginate inner core and an enzyme “decorated” chitosan shell that are shown to preclude bacterial QS crosstalk, minimizing QS mediated behaviors.
GTC/CanariCam Mid-IR Imaging of the Fullerene-rich Planetary Nebula IC 418: Searching for the Spatial Distribution of Fullerene-like Molecules
Authors: Díaz-Luis J. J. , García-Hernández D. A. , Manchado A. , García-Lario P. , Villaver E. , García-Segura G.
Published: February 2018

We present seeing-limited narrow-band mid-IR GTC/CanariCam images of the spatially extended fullerene-containing planetary nebula (PN) IC 418. The narrow-band images cover the C60 fullerene band at 17.4 μm, the polycyclic aromatic hydrocarbon like (PAH-like) feature at 11.3 μm, the broad 9–13 μm feature, and their adjacent continua at 9.8 and 20.5 μm. We study the relative spatial distribution of these complex species, all detected in the Spitzer and Infrared Space Observatory spectra of IC 418, with the aim of getting observational constraints to the formation process of fullerenes in H-rich circumstellar environments. A similar ring-like extended structure is seen in all narrow-band filters, except in the dust continuum emission at 9.8 μm, which peaks closer to the central star. The continuum-subtracted images display a clear ring-like extended structure for the carrier of the broad 9–13 μm emission, while the spatial distribution of the (PAH-like) 11.3 μm emission is not so well defined. Interestingly, a residual C60 17.4 μm emission (at about 4σ from the sky background) is seen when subtracting the dust continuum emission at 20.5 μm. This residual C60 emission, if real, might have several interpretations, the most exciting being perhaps that other fullerene-based species like hydrogenated fullerenes with very low H-content may contribute to the observed 17.4 μm emission. We conclude that higher sensitivity mid-IR images and spatially resolved spectroscopic observations (especially in the Q-band) are necessary to get some clues about fullerene formation in PNe.
Investigating the Binarity of S0-2: Implications for Its Origins and Robustness as a Probe of the Laws of Gravity around a Supermassive Black Hole
Authors: Chu Devin S. , Do Tuan , Hees Aurelien , Ghez Andrea , Naoz Smadar , Witzel Gunther , Sakai Shoko , Chappell Samantha , Gautam Abhimat K. , Lu Jessica R. , Matthews Keith
Published: February 2018

The star S0-2, which orbits the supermassive black hole (SMBH) in our Galaxy with a period of 16 years, provides the strongest constraint on both the mass of the SMBH and the distance to the Galactic center. S0-2 will soon provide the first measurement of relativistic effects near a SMBH. We report the first limits on the binarity of S0-2 from radial velocity (RV) monitoring, which has implications for both understanding its origin and robustness as a probe of the central gravitational field. With 87 RV measurements, which include 12 new observations that we present, we have the requisite data set to look for RV variations from S0-2′s orbital model. Using a Lomb–Scargle analysis and orbit-fitting for potential binaries, we detect no RV variation beyond S0-2′s orbital motion and do not find any significant periodic signal. The lack of a binary companion does not currently distinguish different formation scenarios for S0-2. The upper limit on the mass of a companion star (

) still allowed by our results has a median upper limit of

 sin i ≤ 1.6 M
⊙ for periods between 1 and 150 days, the longest period to avoid tidal break-up of the binary. We also investigate the impact of the remaining allowed binary system on the measurement of the relativistic redshift at S0-2′s closest approach in 2018. While binary star systems are important to consider for this experiment, we find that plausible binaries for S0-2 will not alter a 5σ detection of the relativistic redshift.
Convective Dynamics and Disequilibrium Chemistry in the Atmospheres of Giant Planets and Brown Dwarfs
Authors: Bordwell Baylee , Brown Benjamin P. , Oishi Jeffrey S.
Published: February 2018

Disequilibrium chemical processes significantly affect the spectra of substellar objects. To study these effects, dynamical disequilibrium has been parameterized using the quench and eddy diffusion approximations, but little work has been done to explore how these approximations perform under realistic planetary conditions in different dynamical regimes. As a first step toward addressing this problem, we study the localized, small-scale convective dynamics of planetary atmospheres by direct numerical simulation of fully compressible hydrodynamics with reactive tracers using the Dedalus code. Using polytropically stratified, plane-parallel atmospheres in 2D and 3D, we explore the quenching behavior of different abstract chemical species as a function of the dynamical conditions of the atmosphere as parameterized by the Rayleigh number. We find that in both 2D and 3D, chemical species quench deeper than would be predicted based on simple mixing-length arguments. Instead, it is necessary to employ length scales based on the chemical equilibrium profile of the reacting species in order to predict quench points and perform chemical kinetics modeling in 1D. Based on the results of our simulations, we provide a new length scale, derived from the chemical scale height, that can be used to perform these calculations. This length scale is simple to calculate from known chemical data and makes reasonable predictions for our dynamical simulations.
Decrease in Hysteresis of Planetary Climate for Planets with Long Solar Days
Authors: Abbot Dorian S. , Bloch-Johnson Jonah , Checlair Jade , Farahat Navah X. , Graham R. J. , Plotkin David , Popovic Predrag , Spaulding-Astudillo Francisco
Published: February 2018

The ice-albedo feedback on rapidly rotating terrestrial planets in the habitable zone can lead to abrupt transitions (bifurcations) between a warm and a snowball (ice-covered) state, bistability between these states, and hysteresis in planetary climate. This is important for planetary habitability because snowball events may trigger rises in the complexity of life, but could also endanger complex life that already exists. Recent work has shown that planets tidally locked in synchronous rotation states will transition smoothly into the snowball state rather than experiencing bifurcations. Here we investigate the structure of snowball bifurcations on planets that are tidally influenced, but not synchronously rotating, so that they experience long solar days. We use PlaSIM, an intermediate-complexity global climate model, with a thermodynamic mixed layer ocean and the Sun’s spectrum. We find that the amount of hysteresis (the range in stellar flux for which there is bistability in climate) is significantly reduced for solar days with lengths of tens of Earth days, and disappears for solar days of hundreds of Earth days. These results suggest that tidally influenced planets orbiting M and K stars that are not synchronously rotating could have much less hysteresis associated with the snowball bifurcations than they would if they were rapidly rotating. This implies that the amount of time it takes them to escape a snowball state via CO2 outgassing would be greatly reduced, as would the period of cycling between the warm and snowball state if they have low CO2 outgassing rates.
A large pulmonary cavity replaced by a tuberculosis granuloma and healed during treatment of a patient with tuberculosis
Authors: Chen Ling , Zhang Jianyong , Zhang Hong
Published: February 2018

In the early stages of M. tuberculosis infection, lung tuberculosis (TB) granulomas are often formed at sites of infection to constrain the infection and can undergo healing in most cases or enlarge as the disease progresses in some cases. We present here an unusual case of TB in which a large previously existing pulmonary cavity was replaced by a TB granuloma and then healed during treatment of a patient with poly-resistant TB. This case indicates that the disease process from TB granuloma formation to pulmonary cavities and progression or healing is more diverse than previously thought and could be reversed. An in-depth understanding of the disease process from initiation and maintenance of the TB granuloma to pulmonary cavities and progression or healing will provide new ways to combat mycobacterial infections.