bluuebunny/crossref_metadata_2025 huggingface dataset:
Supuestos epistémicos en el análisis de la movilidad social
Authors: Pla Jésica Lorena
Published: December 2017

El presente artículo tiene como objetivo general identificar la corriente que hegemonizó los estudios de movilidad social desde sus inicios, las implicancias políticas de la misma (en relación con la idea de igualdad), y a la par presentar una alternativa para no desechar la idea de movilidad social, pero insertarla en el estudio complejo, relacional y combinado de los procesos de estructuración de clase. De manera particular, buscamos dar cuenta cómo ambas propuestas tienen efectos diferenciales a la hora de explicar los procesos de igualdad-desigualdad en las sociedades latinoamericanas contemporáneas. Se presenta una síntesis de la postura estructural funcionalista sobre la movilidad social, poniéndola en relación con las inferencias (interpretativas y políticas), que se pueden hacer a partir de la misma y luego una propuesta alternativa para pensar la movilidad social en el ámbito de los procesos de estructuración de clases en los cuales las políticas sociales tienen un rol fundamental, al promover diferentes gradientes de distribución del ingreso, entre otros elementos, con efectos regresivos o redistribuidos sobre la desigualdad de clase. Las trayectorias de clase aparecen como el concepto que conjugarían dichos procesos, dentro de una mirada relacional de las clases sociales.
Alcances y límites del multiculturalismo liberal desde un enfoque de género interseccional
Authors: García-Peter Sabina , Villavicencio-Miranda Luis
Published: December 2017

El artículo presenta un análisis crítico de dos de las posturas teóricas de mayor influencia dentro del multiculturalismo liberal –representadas por Will Kymlicka y Charles Taylor–. Con base en una perspectiva teórico-metodológica de género interseccional, se muestran los alcances y límites de ambas posturas. El análisis señala que el estudio de la diversidad cultural es un asunto que adquiere nuevos y ricos matices cuando se aborda holísticamente, colocando en el centro la relación de las desigualdades de género con otros mecanismos de desigualdad social, como la “raza”/etnicidad y la clase social. Para concluir se propone que sólo al integrar y conectar el estudio de estas variables en la investigación sobre la diversidad cultural, es posible abogar por una política democrática que ponga énfasis en la naturaleza específica de las diferencias, pero dentro los principios de la igualdad y la justicia.
Desigualdades socioecológicas y sufrimiento ambiental en el conflicto “Polimetales” en Arica
Authors: Castillo-Gallardo Mayarí
Published: December 2017

Este artículo indaga en la construcción cultural de las desigualdades socioecológicas, recuperando el concepto de sufrimiento ambiental para el análisis de un territorio de alta degradación ambiental: el caso “Polimetales”, ubicado en la ciudad de Arica, estudiado a través de una metodología etnográfica durante los años 2013, 2014 y 2015. Se busca establecer las formas mediante las cuales los sujetos involucrados en estos territorios padecen dicho sufrimiento ambiental, interpretan las relaciones de desigualdad socioambiental en las que se encuentran, intentan modificarlas o muchas veces las reproducen. Con este análisis, el artículo reflexiona sobre las dinámicas de conflicto en torno a las desigualdades.
Equivalencia y valor en procesos de reciprocidad e intercambio entre los mapuches
Authors: Tereucán-Angulo Julio , Briceño-Olivera Claudio , Gálvez-Nieto José
Published: December 2017

La reciprocidad y el intercambio constituyen un tema de tratamiento en la antropología a partir del ensayo sobre los dones de Marcel Mauss; no obstante, esta temática ha tenido un escaso tratamiento entre los mapuches, especialmente desde la óptica de las prácticas sociales que personas y grupos domésticos realizan en las comunidades rurales. El objetivo del artículo es analizar la reciprocidad y el intercambio desde la perspectiva de la intercambiabilidad y procesos asociados en comunidades mapuches, para posteriormente dimensionar los principios involucrados, en particular los referidos a equivalencia y valor en la reciprocidad; postulando que a partir del análisis de estas prácticas se puede entender y comprender la organización social, la dinámica de relaciones económicas, las interrelaciones sociales cotidianas entre grupos domésticos, entre otros ámbitos. La investigación es de tipo cualitativa bajo el método etnográfico y se realizó en comunidades mapuches del sur de Chile.
Etnicidad, género y educación superior. Trayectorias de dos mujeres arhuacas en Colombia
Authors: Santamaria Angela
Published: December 2017

Nos preguntamos en este texto, ¿cómo han enfrentado estas lideresas las restricciones culturales frente a las exigencias de la vida pública ¿Cómo han creado una amalgama de capitales y saberes diversos en el marco de sus liderazgos? Los principales elementos teóricos utilizados en este trabajo son: la perspectiva sociológica y la Teoría de los campos de Bourdieu, los estudios sobre interseccionalidad de Lorde (1984) y Pratt-Clarke (2010), los estudios de Gil (2005), Choque (2015) y Mato (2015) sobre educación superior intercultural, y finalmente los estudios sobre liderazgos femeninos de Lumby y Coleman (2007). Metodológicamente trabajamos a partir de la reconstrucción de dos trayectorias personales escolares y profesionales desde una perspectiva interseccional.
Formulasi dan Evaluasi Sediaan Edible Film dari Ekstrak Daun Kemangi (Ocimum americanum L.) sebagai Penyegar Mulut
Authors: Harmely Fifi , Deviarny Chris , Yenni Wenna Syukri
Published: December 2017

Penelitian tentang formulasi edible film dari ekstrak daun kemangi sebagai penyegar mulut telah dilakukan. Ekstrak daun kemangi digunakan dalam berbagai konsentrasi yaitu 2,5%, 5% dan 7,5%. Produk dievaluasi untuk beberapa parameter seperti organoleptik, kerapuhan, pengeringan penyusutan, pH, ketebalan, isi flavonoid dan responden preferensi. Hasil evaluasi menunjukkan bahwa edible film dari ekstrak daun kemangi memenuhi persyaratan seperti yang dipersyaratkan oleh Standar Nasional Indonesia (SNI) dan memiliki kualitas seperti produk di pasar. Analisis statistik menggunakan uji Kruskal Wallis menunjukkan bahwa responden lebih suka untuk formulasi F0 dalam hal penampilan mereka dan rasa sementara sebagai penyegar mulut, responden lebih memilih formulasi F3.
Pengaruh Pemberian Vanadil Sulfat dan Kromium (III) Klorida terhadap Fungsi Ginjal Mencit Putih Diabetes
Authors: Dillasamola Dwisari , Dharma Surya , Arifin Helmi
Published: December 2017

Tujuan dari penelitian ini adalah untuk mengetahui pengaruh dari dua logam berat vanadil sulfat dan krom (III) klorida pada tingkat kreatinin darah tikus putih hiperglikemia yang disebabkan oleh deksametason 11mg/kgBB. Hewan-hewan percobaan dikelompokkan menjadi lima kelompok yang terdiri dari 5 tikus putih. Kelompok I digunakan sebagai kelompok kontrol, yang hanya menerima makanan standar dan suplemen makanan. Kelompok II - V diinduksi dengan dexametason 11mg/ kgBB untuk meningkatkan kadar glukosa mereka. Kelompok III juga diberikan kromium (III) klorida 5,2 ug/ 20g BW. Kelompok IV juga diberi vanadil sulfat pada dosis 0,78 mg/ 20 gBB. Kelompok V menerima kombinasi vanadil sulfat dengan dosis 0,39 mg/ 20 gBB dan kromium (III) klorida pada dosis 2,6 ug/ 20 gBB. Tingkat kreatinin darah ditentukan dengan metode enzimatik yang dilakukan selama 42 hari dan pengamatan dilakukan pada hari ke-7, hari ke-21 dan hari ke-42. Penelitian ini menyimpulkan bahwa pemberian kombinasi vanadil sulfat dan kromium (III) klorida secara signifikan mengurangi tingkat kreatinin darah tikus putih (P <0,05).
Perbandingan Efektivitas Pendidikan Kesehatan terhadap Pengetahuan dan Kemampuan Ibu Merawat Balita ISPA di Puskesmas Padang Pasir dan Pauh
Authors: Novrianda Dwi , Lucida Henny , Soumariris Irfandy
Published: December 2017

Pendidikan kesehatan dengan media booklet merupakan upaya meningkatkan kemampuan merawat Infeksi Saluran Pernapasan Akut (ISPA). Penelitian ini bertujuan untuk mengetahui perbandingan efektivitas pendidikan kesehatan terhadap pengetahuan dan kemampuan ibu dalam perawatan balita ISPA antara Puskesmas Padang Pasir dan Pauh. Metode yang digunakan adalah preeksperimental dengan pretest posttest design. Subjek penelitian adalah ibu dengan balita ISPA berjumlah 15. Pengumpulan data menggunakan kuesioner. Analisis data menggunakan uji Wilcoxon untuk menilai perbedaan pengetahuan dan kemampuan merawat pada pretest posttest dan Mann Whitney-U untuk menilai perbandingan antar Puskesmas. Hasil penelitian diperoleh perbedaan pengetahuan dan kemampuan merawat balita ISPA sebelum dan setelah pendidikan kesehatan dengan (p=0,002). Lebih lanjut terdapat perbedaan efektivitas pendidikan kesehatan antara Puskesmas Padang Pasir dengan Pauh pada kemampuan merawat (p=0,004). Oleh karena itu pendidikan kesehatan tentang ISPA dengan media yang lebih menarik seperti booklet perlu diberikan terutama pada ibu untuk meningkatkan pengetahuan dan kemampuan merawat balita dengan ISPA.
Pengaruh Pemberian Fibroblast Growth Factor (FGF) dari Telur Ayam Terfertilisasi Terhadap Kadar Glukosa Darah Mencit Hiperglikemia
Authors: Dewi Irene Puspa , Dharma Surya , Marlina Marlina
Published: December 2017

Telah dilakukan penelitian tentang pengaruh pemberian Fibroblast Growth Factor (FGF) yang berasal dari telur ayam terfertilisasi terhadap kadar glukosa darah mencit yang diinduksi aloksan. FGF diambil dari putih telur ayam terfertilisasi, kemudian putih telur tersebut dikeringkan dengan metode Freeze Dryer dan diserbukkan hingga menjadi tepung putih telur. Tepung putih telur diuji secara kuantitatif dengan metode ELISA (The Enzimed - Link Immunosorbent Assay) untuk menentukan kadar FGF yang terkandung didalamnya. FGF tersebut diberikan kepada mencit hiperglikemia yang induksi aloksan. Dilakukan pengamatan kadar glukosa darah mencit secara periodik setiap minggu selama 4 minggu setelah pemberian sediaan FGF. Hasil yang didapat bahwa didalam tepung putih telur ayam terfertilisasi terkandung FGF dengan kadar 219 ng/L dan pemberian FGF terhadap mencit hiperglikemia mampu memperbaiki kadar glukosa darah mencit hiperglikemia.
Formulasi Tablet Lepas Lambat Natrium Diklofenak Menggunakan Pati Pisang Kepok (Musa balbisiana L) Sebagai Matriks
Authors: Anggraini Deni , Lukman Anita , Mulyani Ria
Published: December 2017

Telah dilakukan formulasi tablet lepas lambat Natrium Diklofenak menggunakan matriks pati pisang kepok dan natrium karboksil metil selulosa sebagai pembandingnya. Tujuan penelitian ini untuk mengetahui apakah sediaan lepas lambat yang dibuat dengan matriks pati pisang kepok memenuhi persyaratan tablet lepas lambat. Hasil uji disolusi menunjukan formula I (Pati Pisang Kepok) terdisolusi sebesar 110,24 %, formula II (Natrium Karboksil Metil Selulosa) sebesar 39,04 % dalam waktu 8 jam. Dari hasil uji disolusi menunjukan bahwa pati pisang kepok belum memenuhi persyaratan sebagai matriks karena belum dapat memperlambat laju disolusi. Kinetika pelepasan zat aktif dari matriks antara kedua formula mengikuti persamaan Higuchi.
A Decolonial Primer
Authors: Medina Néstor
Published: December 2017

In the form of foundational material required to understand decolonial thinking, this article is organized in four parts. The first section discusses the connections between decolonial thinking and other social movements; decolonial thinkers build on the insights of previous discourses and social movements, even while further developing them. The second section shows how decolonial thinking includes a radical theoretical reframing of our understanding of modernity, its emergence, and its connection to the Western European colonial project. For decolonial thinkers, modernity is predicated on domination and colonization and cannot be understood unless viewed from the perspective of its underside. The third section demonstrates that the adoption of a decolonial theoretical frame means an epistemological reconfiguration and challenging of Western European and Anglo North Atlantic forms of knowledge as the most developed expression of human “advance.” Instead, they engage in the act of reclaiming the forms of knowledge of the other peoples and cultures of the world. The fourth section suggests the Latina/o theological notion of mestizaje as a concrete example of how in different contexts decolonizing impetuses are emerging. Crucial here is the emphasis that while the use of mestizaje in theology resonates with decolonizing impetuses, it predates its theoretical articulation.
Singing as Un Saber del Sur, or Another Way of Knowing
Authors: Whitla Becca
Published: December 2017

In this article, I show how one song, “El Espíritu de Dios,” can be a source of knowledge and an act of epistemic disobedience, even amid the increasingly complex dynamics of the “coloniality of music.” When it is sung in embodied ways from below, it affirms knowledge as something that emerges out of the oral tradition arising from the heart of a community's life and experience. It is understood to belong to the community, in this case multiple local Latin American communities. This embodied, oral, communal singing challenges prevailing Eurocentric norms that emphasize written texts, individual ownership, and rationalist intellectualism, represented in Euro-North-Atlantic epistemologies of the Enlightenment. When it is sung as a fully embodied holistic human expression, it instead actualizes an act of hope, another way of knowing, un saber del sur (knowledge from the South), which defies forces that oppress and the pervasiveness of coloniality. Who we are and who we want to become as active agents of a liberative praxis proclaiming what is and what ought to be, the already and not yet of the Reign of God, emerges. Understanding the dynamics of (de)coloniality in hymns and songs involves affirming songs like “El Espíritu de Dios,” which express an-other way of knowing and singing and a decolonial mode for doing theology.
Reduction of shunt dependency rates following aneurysmal subarachnoid hemorrhage by tandem fenestration of the lamina terminalis and membrane of Liliequist during microsurgical aneurysm repair
Authors: Winkler Ethan A. , Burkhardt Jan-Karl , Rutledge W. Caleb , Rick Jonathan W. , Partow Carlene P. , Yue John K. , Birk Harjus , Bach Ashley M. , Raygor Kunal P. , Lawton Michael T.
Published: December 2017

OBJECTIVE

Shunt-dependent hydrocephalus is an important cause of morbidity following aneurysmal subarachnoid hemorrhage (aSAH) in excess of 20% of cases. Hydrocephalus leads to prolonged hospital and ICU stays, well as to repeated surgical interventions, readmissions, and complications associated with ventriculoperitoneal (VP) shunts, including shunt failure and infection. Whether variations in surgical technique at the time of aneurysm treatment may modify rates of shunt dependency remains a matter of debate. Here, the authors report on their experience with tandem fenestration of the lamina terminalis (LT) and membrane of Liliequist (MoL) at the time of open microsurgical repair of the ruptured aneurysm.

METHODS

The authors conducted a retrospective review of 663 consecutive patients with aSAH treated from 2005 to 2015 by open microsurgery via a pterional or orbitozygomatic craniotomy by the senior author (M.T.L.). Data collected from review of the electronic medical record included age, Hunt and Hess grade, Fisher grade, need for an external ventricular drain, and opening pressure. Patients were stratified into those undergoing no fenestration and those undergoing tandem fenestration of the LT and MoL at the time of surgical repair. Outcome variables, including VP shunt placement and timing of shunt placement, were recorded and statistically analyzed.

RESULTS

In total, shunt-dependent hydrocephalus was observed in 15.8% of patients undergoing open surgical repair following aSAH. Tandem microsurgical fenestration of the LT and MoL was associated with a statistically significant reduction in shunt dependency (17.9% vs 3.2%, p < 0.01). This effect was confirmed with multivariate analysis of collected variables (multivariate OR 0.09, 95% CI 0.03–0.30). Number-needed-to-treat analysis demonstrated that tandem fenestration was required in approximately 6.8 patients to prevent a single VP shunt placement. A statistically significant prolongation in days to VP shunt surgery was also observed in patients treated with tandem fenestration (26.6 ± 19.4 days vs 54.0 ± 36.5 days, p < 0.05).

CONCLUSIONS

Tandem fenestration of the LT and MoL at the time of open microsurgical clipping and/or bypass to secure ruptured anterior and posterior circulation aneurysms is associated with reductions in shunt-dependent hydrocephalus following aSAH. Future prospective randomized multicenter studies are needed to confirm this result.
Cerebrospinal Fluid, MRI, and Florbetaben-PET in Cerebral Amyloid Angiopathy-Related Inflammation
Authors: Renard Dimitri , Collombier Laurent , Demattei Christophe , Wacongne Anne , Charif Mahmoud , Ayrignac Xavier , Azakri Souhayla , Gaillard Nicolas , Boudousq Vincent , Lehmann Sylvain , Menjot de Champfleur Nicolas , Thouvenot Eric
Published: December 2017

Background:

Cerebral amyloid angiopathy-related inflammation (CAA-ri) is associated with a cerebrospinal fluid (CSF) biomarker profile similar to that observed in CAA. Few CAA-ri patients have been studied by fibrillar amyloid-β (Aβ) imaging (using 11C-Pittsburgh compound B and 18F-florbetapir, but not 18F-florbetaben).

Objective:

To describe CSF biomarkers, magnetic resonance imaging (MRI), and 18F-florbetaben (FBB)-positron emission tomography (PET) changes in CAA-ri patients.

Methods:

CSF levels of total tau, phosphorylated tau, Aβ1-42, and Aβ1-40, MRI (cerebral microbleeds count on susceptibility-weighted imaging and semi-quantitative analysis of fluid-attenuation inversion recovery white matter hyperintensities), and FBB-PET (using both cerebellar cortex and pons to calculate standardized uptake value ratios) were analyzed in nine consecutive CAA-ri patients.

Results:

A median number of 769 cerebral microbleeds/patient were counted on MRI. When using the pons as reference region, amyloid load on FBB-PET was very strongly correlated to CSF Aβ1-40 levels (rho = –0.83, p = 0.008) and moderately correlated to cerebral microbleed numbers in the occipital lobes (rho = 0.59, p = 0.001), while comparisons with other CSF biomarkers were not statistically significant (total tau, rho = –0.63, p = 0.076; phosphorylated tau, rho = –0.68, p = 0.05; Aβ1-42, rho = –0.59, p = 0.09). All correlations were weaker, and not statistically significant, when using the cerebellum as reference region. A non-significant correlation (rho = –0.50, p = 0.18) was observed between CSF Aβ1-40 levels and cerebral microbleed numbers.

Conclusion:

In CAA-ri, CSF Aβ1-40 levels correlated well with amyloid load assessed by FBB-PET when the pons was used as reference, and to a lesser degree with cerebral microbleeds count on MRI. This confirms earlier data on CSF Aβ1-40 as an in vivo marker for CAA and CAA-ri.
Mesenchymal Stem Cell-Derived Extracellular Vesicles Suppresses iNOS Expression and Ameliorates Neural Impairment in Alzheimer’s Disease Mice
Authors: Wang Shan-Shan , Jia Jianjun , Wang Zhenfu
Published: December 2017

Background:

Mesenchymal stem cells (MSCs)-derived extracellular vesicles (EVs) have been reported to exhibit therapeutic effects in various animal models of neurological diseases, such as stroke and hypoxic-ischemic brain injury.

Objective:

The present study investigated the potential beneficial effect of MSC-derived EVs in an animal model of Alzheimer’s disease (AD).

Methods:

APP/PS1 mice and their non-transgenic littermates (WT) received intracerebroventricle injection of MSC-derived EVs once per two days for two weeks. Then novel object recognition and water maze tasks were carried out to measure the cognitive behaviors. Electrophysiological tests were carried out to measure hippocampal synaptic plasticity. Inducible nitric oxide synthase (iNOS) mRNA and protein levels were measured by qRT-PCR and western blotting in primary cultured neurons treated with amyloid-β peptide (Aβ) or prepared from APP/PS1 mice.

Results:

Treatment with MSC-derived EVs alleviates exogenous Aβ-induced iNOS mRNA and protein expression. In cultured primary neurons prepared from APP/PS1 pups, iNOS mRNA and protein levels were significantly reduced when treated with MSC-derived EVs. MSC-derived EVs improved cognitive behavior, rescued impairment of CA1 synaptic transmission, and long-term potentiation in APP/PS1 mice.

Conclusion:

MSC-derived EVs possessed beneficial effects in a mouse model of AD, probably by suppressing Aβ induced iNOS expression.
Printing Speed and Quality Enhancement by Controlling the Surface Energy of Cliché in Reverse Offset Printing
Authors: Cho Young , Jeong Yeonho , Kim Youn , Kwon Sin , Lee Seung-Hyun , Kim Kwang , Kang Dongwoo , Lee Taik-Min
Published: December 2017

Printed electronics is one of the emerging technologies owing to its low cost and productivity. Recently, many researchers tried to adapt printing technology to the fabrication of fine electronic patterns on flexible substrates, including the gate line of thin film transistors. In this study, we fabricated a flexible cliché using the nanoimprint process and used it in reverse offset printing. Then, we analyzed the effect of the surface energy of the imprinted cliché on process parameters, such as printing speed and rolling direction. We showed that the productivity of the process and quality of printed pattern can be considerably enhanced by controlling the surface energy of the cliché. When a flexible cliché is manufactured using a resin with a surface energy considerably different from that of the blanket, the ink can be detached easily and fine patterns can be engraved successfully regardless of the pattern shape.
“I Learned to Let Go of My Pain”. The Effects of Mindfulness Meditation on Adolescents with Chronic Pain: An Analysis of Participants’ Treatment Experience
Authors: Ruskin Danielle , Harris Lauren , Stinson Jennifer , Kohut Sara , Walker Katie , McCarthy Erinn
Published: December 2017

Chronic pain can lead to significant negative outcomes across many areas of life. Recently, mindfulness-based interventions (MBIs) have been identified as potentially effective tools for improved pain management among adolescents living with pain. This study aimed to explore the experience of adolescents who participated in an eight-week mindfulness group adapted for adolescents with chronic pain (MBI-A), and obtain their feedback and suggestions on group structure and content. A mixed method design was used employing qualitative data from focus groups and data from a satisfaction questionnaire. Focus group data were transcribed and analyzed using inductive simple descriptive content analysis. Of the total participants (n = 21), 90% (n = 19) provided feedback by completing satisfaction questionnaires and seventeen (n = 17) of those also participated across two focus groups. Analysis of the focus group transcripts uncovered six themes: mindfulness skills, supportive environment, group exercises (likes and dislikes), empowerment, program expectations, and logistics. Participants reported positive experiences in the MBI-A program, including support received from peers and mindfulness skills, including present moment awareness, pain acceptance, and emotion regulation. Group members suggested increasing the number of sessions and being clearer at outset regarding a focus on reduction of emotional suffering rather than physical pain.
Action Spectrum on UVA Irradiation for Formation of Persistent Pigmentation in Normal Japanese Individuals
Authors: Maeda Kazuhisa
Published: December 2017

The minimum exposure required to produce persistent pigmentation (PP) on the skin of normal Japanese subjects was evaluated by means of monochromatic irradiation on the back using a high-intensity monochromator. PP was induced within the range of wavelengths up to 468 nm, with a peak from 330 to 370 nm, but it was not observed at 482 or 497 nm. When the PP production curve was obtained taking the spectral distribution of sunlight into account, it showed a peak at 340 nm centering in the UVA region and extending into the region up to 396 nm. Thus, it appears that solar UVA participates in PP formation.
Extremal Matching Energy of Random Polyomino Chains
Authors: Wu Tingzeng , Lü Huazhong , Zhang Xuexin
Published: December 2017

Polyomino graphs is one of the research objectives in statistical physics and in modeling problems of surface chemistry. A random polyomino chain is a subgraph of a polyomino graph. The matching energy is defined as the sum of the absolute values of the zeros of the matching polynomial of a graph. In this paper, we characterize the graphs with the extremal matching energy among all random polyomino chains of a polyomino graph by the probability method.
Online Optimal Switching Frequency Selection for Grid-Connected Voltage Source Inverters
Authors: Albatran Saher , Smadi Issam , Ahmad Hamzeh , Koran Ahmed
Published: December 2017

Enhancing the performance of the voltage source inverters (VSIs) without changing the hardware structure has recently acquired an increased amount of interest. In this study, an optimization algorithm, enhancing the quality of the output power and the efficiency of three-phase grid connected VSIs is proposed. Towards that end, the proposed algorithm varies the switching frequency (fsw) to maintain the best balance between switching losses of the insulated-gate-bipolar-transistor (IGBT) power module as well as the output power quality under all loading conditions, including the ambient temperature effect. Since there is a contradiction with these two measures in relation to the switching frequency, the theory of multi-objective optimization is employed. The proposed algorithm is executed on the platform of Altera® DE2-115 field-programmable-gate-array (FPGA) in which the optimal value of the switching frequency is determined online without the need for heavy offline calculations and/or lookup tables. With adopting the proposed algorithm, there is an improvement in the VSI efficiency without degrading the output power quality. Therefore, the proposed algorithm enhances the lifetime of the IGBT power module because of reduced variations in the module’s junction temperature. An experimental prototype is built, and experimental tests are conducted for the verification of the viability of the proposed algorithm.
An Improved Lubrication Model between Piston Rings and Cylinder Liners with Consideration of Liner Dynamic Deformations
Authors: Li Guoxing , Gu Fengshou , Wang Tie , Lu Xingchen , Zhang Li , Zhang Chunfeng , Ball Andrew
Published: December 2017

The friction pair of piston rings and cylinder liner is one of the most important friction couplings in an internal combustion engine. It influences engine efficiency and service life. Under the excitation of piston slaps, the dynamic deformation of cylinder liner is close to the surface roughness magnitudes, which can affect the friction and lubrication performance between the piston rings and cylinder assemblies. To investigate the potential influences of structural deformations to tribological behaviours of cylinder assemblies, the dynamic deformation of the inner surface due to pistons slaps is obtained by dynamic simulations, and then coupled into an improved lubrication model. Different from the traditional lubrication model which takes the pressure stress factor and shear stress factor to be constant, the model proposed in this paper calculated these factors in real time using numerical integration to achieve a more realistic simulation. Based on the improved piston rings and cylinder liner lubrication model, the minimum oil film thickness and friction force curves are obtained for an entire work cycle. It shows that the friction force obtained from the improved model manifests clear oscillations in each stoke, which is different from the smoothed profiles predicted traditionally. Moreover, the average amplitude of the friction forces also shows clear reduction.
Power Swing Generated in Francis Turbines by Part Load and Overload Instabilities
Authors: Valentín David , Presas Alexandre , Egusquiza Eduard , Valero Carme , Egusquiza Mònica , Bossio Matias
Published: December 2017

Hydropower plays a key role in the actual energy market due to its fast response and regulation capacity. In that way, hydraulic turbines are increasingly demanded to work at off-design conditions, where complex flow patterns and cavitation appear, especially in Francis turbines. The draft tube cavitation surge is a hydraulic phenomenon that appears in Francis turbines below and above its Best Efficiency Point (BEP). It is a low frequency phenomenon consisting of a vortex rope in the runner outlet and draft tube, which can become unstable when its frequency coincides with a natural frequency of the hydraulic circuit. At this situation, the output power can significantly swing, endangering the electrical grid stability. This study is focused on the detection of these instabilities in Francis turbines and their relationship with the output power swings. To do so, extensive experimental tests for different operating conditions have been carried out in a large prototype Francis turbine (444 MW of rated power) within the frame of the European Project Hyperbole (FP7-ENERGY-2013-1). Several sensors have been installed in the hydraulic circuit (pressure sensors in the draft tube, spiral casing, and penstock), in the rotating and static structures (vibration sensors, proximity probes, and strain gauges in the runner and in the shaft), as well as in the electrical side (output power, intensity, and voltage). Moreover, a numerical Finite Element Method (FEM) has been also used to relate the hydraulic excitation with the output power swing.
Multi-Objective Coordinated Planning of Distributed Generation and AC/DC Hybrid Distribution Networks Based on a Multi-Scenario Technique Considering Timing Characteristics
Authors: Yang Yongchun , Wang Xiaodan , Luo Jingjing , Duan Jie , Gao Yajing , Li Hong , Xiao Xiangning
Published: December 2017

With increased direct current (DC) load density and the penetration of a large number of distributed generation (DG) units in alternating current (AC) distribution networks (DNs); a planning approach that considers transforming some of the AC lines into DC lines and building the DC network is proposed. Considering the DG output uncertainty and the load fluctuation, a planning model for an AC/DC hybrid distribution network (DN) with the DG based on the construction of multi-scenario technology with timing characteristics is built. In the DG configuration planning model, the lines to be transformed into DC form the access location and the decision regarding the DC or AC form of the newly built lines are considered optimizing variables. The DG investment, the network and converters of the DG and load, the active power loss and the voltage stability are considered in the objective functions. An improved adaptive niche genetic algorithm based on the fuzzy degree of membership and variance weighting is used to solve the nested model. Finally, considering the improved electrical and electronic engineers 33 (IEEE33) node system as an example, the correctness and effectiveness of the proposed planning method are verified. Compared to the plan without transforming some of the AC lines into DC lines and building a DC network, more DG can be admitted, and the economic cost of the AC/DC hybrid DN is notably decreased when planning to transform some of the AC lines into DC lines and build a DC network. The active power network loss and the voltage stability index are similarly further optimized.
An Experimental Study on the Radiation Noise Characteristics of a Centrifugal Pump with Various Working Conditions
Authors: Guo Chang , Gao Ming , Lu Dongyue , Wang Kun
Published: December 2017

To investigate the radiation noise characteristics of a centrifugal pump under various working conditions, a noise measurement system is established; afterwards, the distribution of different points and intervals, as well as the overall level of noise, are studied. The total sound pressure level distribution for different points manifests the dipole and asymmetric directivity characteristics. Additionally, the acoustic energy is introduced to compare the noise of different intervals to reveal the asymmetric characteristics, and it is found that variation in working conditions has little impact on the acoustic energy distribution, and the ratio of the acoustic energy in the direction facing the tongue, as well as that in the direction against the tongue, to total acoustic energy fluctuate around 0.410 and 0.160, respectively, under various working conditions. Also, the A-weighted average sound pressure level (LpA) is applied to describe the overall level of noise, and LpA increases gradually with the growth of rotational speed, but the growth slope decreases. While in the operation of throttling regulation, LpA shows the trend that first increases, then remains stable, and increases again with the growth of flow rate. This study could provide guidance for optimizing the operating conditions and noise control of centrifugal pumps.
A Digitally Controlled Power Converter for an Electrostatic Precipitator
Authors: Villegas Pedro , Martín-Ramos Juan , Díaz Juan , Martínez Juan , Prieto Miguel , Pernía Alberto
Published: December 2017

Electrostatic precipitators (ESPs) are devices used in industry to eliminate polluting particles in gases. In order to supply them, an interface must be included between the three-phase main line and the required high DC voltage of tens of kilovolts. This paper describes an 80-kW power supply for such an application. Its structure is based on the series parallel resonant converter with a capacitor as output filter (PRC-LCC), which can adequately cope with the parasitic elements of the step-up transformer involved. The physical implementation of the prototype includes the use of silicon carbide—SiC—semiconductors, which provide better switching capabilities than their traditional silicon—Si—counterparts. As a result, a new control strategy results as a better alternative in which the resonant current is maintained in phase with the first harmonic of the inverter voltage. Although this operation mode imposes hard switching in one of the inverter legs, it minimizes the reactive energy that circulates through the resonant tank, the resonant current amplitude itself and the switching losses. Overall efficiency of the converter benefits from this. These ideas are supported mathematically using the steady state and dynamic models of the topology. They are confirmed with experimental measurements that include waveforms, Bode plots and thermal behavior. The experimental setup delivers 80 kW with an estimated efficiency of 98%.
Teacher Rated School Ethos and Student Reported Bullying—A Multilevel Study of Upper Secondary Schools in Stockholm, Sweden
Authors: Modin Bitte , Låftman Sara , Östberg Viveca
Published: December 2017

School ethos refers to the school leadership’s purposive efforts to shape and direct the attitudes, values and behaviors needed in order to promote an active learning environment and to prevent the emergence of undesirable behaviors by creating shared meaning and common goals for the school. The aim of this study was to examine how teacher rated aspects of school ethos are linked with manifestations of bullying among 11th grade students. Five teacher-rated sub-dimensions of school ethos (staff stability, teacher morale, structure-order, student focus, and academic atmosphere) were examined in relation to student-reported perpetration of and exposure to traditional school bullying and cyberbullying. The data material combines student and teacher information from two separate data collections performed in 2016, comprising teachers and students in 58 upper secondary schools in Stockholm. Analyses showed that bullying was associated with all but one of the five sub-dimensions of school ethos, namely structure and order for dealing with bullying behaviors at the school. Results are discussed in light of this counter-intuitive finding. Our findings nevertheless lend support to the idea that the social organization of schools, as reflected in their teacher-rated ethos, can affect individual students’ attitudes in a way that prevents the emergence of bullying behavior among students.
Non-Linear Relationship between Economic Growth and CO2 Emissions in China: An Empirical Study Based on Panel Smooth Transition Regression Models
Authors: Wang Zheng-Xin , Hao Peng , Yao Pei-Yi
Published: December 2017

The non-linear relationship between provincial economic growth and carbon emissions is investigated by using panel smooth transition regression (PSTR) models. The research indicates that, on the condition of separately taking Gross Domestic Product per capita (GDPpc), energy structure (Es), and urbanisation level (Ul) as transition variables, three models all reject the null hypothesis of a linear relationship, i.e., a non-linear relationship exists. The results show that the three models all contain only one transition function but different numbers of location parameters. The model taking GDPpc as the transition variable has two location parameters, while the other two models separately considering Es and Ul as the transition variables both contain one location parameter. The three models applied in the study all favourably describe the non-linear relationship between economic growth and CO2 emissions in China. It also can be seen that the conversion rate of the influence of Ul on per capita CO2 emissions is significantly higher than those of GDPpc and Es on per capita CO2 emissions.
Genome-Wide Profiling of Small RNAs and Degradome Revealed Conserved Regulations of miRNAs on Auxin-Responsive Genes during Fruit Enlargement in Peaches
Authors: Shi Mengya , Hu Xiao , Wei Yu , Hou Xu , Yuan Xue , Liu Jun , Liu Yueping
Published: December 2017

Auxin has long been known as a critical phytohormone that regulates fruit development in plants. However, due to the lack of an enlarged ovary wall in the model plants Arabidopsis and rice, the molecular regulatory mechanisms of fruit division and enlargement remain unclear. In this study, we performed small RNA sequencing and degradome sequencing analyses to systematically explore post-transcriptional regulation in the mesocarp at the hard core stage following treatment of the peach (Prunus persica L.) fruit with the synthetic auxin α-naphthylacetic acid (NAA). Our analyses identified 24 evolutionarily conserved miRNA genes as well as 16 predicted genes. Experimental verification showed that the expression levels of miR398 and miR408b were significantly upregulated after NAA treatment, whereas those of miR156, miR160, miR166, miR167, miR390, miR393, miR482, miR535 and miR2118 were significantly downregulated. Degradome sequencing coupled with miRNA target prediction analyses detected 119 significant cleavage sites on several mRNA targets, including SQUAMOSA promoter binding protein–like (SPL), ARF, (NAM, ATAF1/2 and CUC2) NAC, Arabidopsis thaliana homeobox protein (ATHB), the homeodomain-leucine zipper transcription factor revoluta(REV), (teosinte-like1, cycloidea and proliferating cell factor1) TCP and auxin signaling F-box protein (AFB) family genes. Our systematic profiling of miRNAs and the degradome in peach fruit suggests the existence of a post-transcriptional regulation network of miRNAs that target auxin pathway genes in fruit development.
Simvastatin Inhibits Cell Proliferation and Migration in Human Anaplastic Thyroid Cancer
Authors: Chen Mei-Chieh , Tsai Yuan-Chin , Tseng Jen-Ho , Liou Jr-Jiun , Horng Steve , Wen Heng-Ching , Fan Yu-Ching , Zhong Wen-Bin , Hsu Sung-Po
Published: December 2017

Malignant human anaplastic thyroid cancer (ATC) is pertinacious to conventional therapies. The present study investigated the anti-cancer activity of simvastatin and its underlying regulatory mechanism in cultured ATC cells. Simvastatin (0–20 μM) concentration-dependently reduced cell viability and relative colony formation. Depletions of mevalonate (MEV) and geranylgeranyl pyrophosphate (GGpp) by simvastatin induced G1 arrest and increased apoptotic cell populations at the sub-G1 phase. Adding MEV and GGpp prevented the simvastatin-inhibited cell proliferation. Immunoblotting analysis illustrated that simvastatin diminished the activation of RhoA and Rac1 protein, and this effect was prevented by pre-treatment with MEV and GGpp. Simvastatin increased the levels of p21cip and p27kip proteins and reduced the levels of hyperphosphorylated-Rb, E2F1 and CCND1 proteins. Adding GGpp abolished the simvastatin-increased levels of p27kip protein, and the GGpp-caused effect was abolished by Skp2 inhibition. Introduction of Cyr61 siRNA into ATC cells prevented the epidermal growth factor (EGF)-enhanced cell migration. The EGF-induced increases of Cyr61 protein expression and cell migration were prevented by simvastatin. Taken together, these results suggest that simvastatin induced ATC proliferation inhibition through the deactivation of RhoA/Rac1 protein and overexpression of p21cip and p27kip, and migration inhibition through the abrogation of Cyr61 protein expression.
Advances in Proteomic Techniques for Cytokine Analysis: Focus on Melanoma Research
Authors: Kupcova Skalnikova Helena , Cizkova Jana , Cervenka Jakub , Vodicka Petr
Published: December 2017

Melanoma is a skin cancer with permanently increasing incidence and resistance to therapies in advanced stages. Reports of spontaneous regression and tumour infiltration with T-lymphocytes makes melanoma candidate for immunotherapies. Cytokines are key factors regulating immune response and intercellular communication in tumour microenvironment. Cytokines may be used in therapy of melanoma to modulate immune response. Cytokines also possess diagnostic and prognostic potential and cytokine production may reflect effects of immunotherapies. The purpose of this review is to give an overview of recent advances in proteomic techniques for the detection and quantification of cytokines in melanoma research. Approaches covered span from mass spectrometry to immunoassays for single molecule detection (ELISA, western blot), multiplex assays (chemiluminescent, bead-based (Luminex) and planar antibody arrays), ultrasensitive techniques (Singulex, Simoa, immuno-PCR, proximity ligation/extension assay, immunomagnetic reduction assay), to analyses of single cells producing cytokines (ELISpot, flow cytometry, mass cytometry and emerging techniques for single cell secretomics). Although this review is focused mainly on cancer and particularly melanoma, the discussed techniques are in general applicable to broad research field of biology and medicine, including stem cells, development, aging, immunology and intercellular communication.
microRNAs in Parkinson’s Disease: From Pathogenesis to Novel Diagnostic and Therapeutic Approaches
Authors: Leggio Loredana , Vivarelli Silvia , L’Episcopo Francesca , Tirolo Cataldo , Caniglia Salvo , Testa Nunzio , Marchetti Bianca , Iraci Nunzio
Published: December 2017

Parkinson’s disease (PD) is the most prevalent central nervous system (CNS) movement disorder and the second most common neurodegenerative disease overall. PD is characterized by the progressive loss of dopaminergic (DAergic) neurons in the substantia nigra pars compacta (SNpc) within the midbrain, accumulation of alpha-synuclein (α-SYN) in Lewy bodies and neurites and excessive neuroinflammation. The neurodegenerative processes typically begin decades before the appearance of clinical symptoms. Therefore, the diagnosis is achievable only when the majority of the relevant DAergic neurons have already died and for that reason available treatments are only palliative at best. The causes and mechanism(s) of this devastating disease are ill-defined but complex interactions between genetic susceptibility and environmental factors are considered major contributors to the etiology of PD. In addition to the role of classical gene mutations in PD, the importance of regulatory elements modulating gene expression has been increasingly recognized. One example is the critical role played by microRNAs (miRNAs) in the development and homeostasis of distinct populations of neurons within the CNS and, in particular, in the context of PD. Recent reports demonstrate how distinct miRNAs are involved in the regulation of PD genes, whereas profiling approaches are unveiling variations in the abundance of certain miRNAs possibly relevant either to the onset or to the progression of the disease. In this review, we provide an overview of the miRNAs recently found to be implicated in PD etiology, with particular focus on their potential relevance as PD biomarkers, as well as their possible use in PD targeted therapy.
Hyaluronan Production by Renomedullary Interstitial Cells: Influence of Endothelin, Angiotensin II and Vasopressin
Authors: Stridh Sara , Palm Fredrik , Takahashi Tomoko , Ikegami-Kawai Mayumi , Friederich-Persson Malou , Hansell Peter
Published: December 2017

The content of hyaluronan (HA) in the interstitium of the renal medulla changes in relation to body hydration status. We investigated if hormones of central importance for body fluid homeostasis affect HA production by renomedullary interstitial cells in culture (RMICs). Simultaneous treatment with vasopressin and angiotensin II (Ang II) reduced HA by 69%. No change occurred in the mRNA expressions of hyaluronan synthase 2 (HAS2) or hyaluronidases (Hyals), while Hyal activity in the supernatant increased by 67% and CD44 expression reduced by 42%. The autocoid endothelin (ET-1) at low concentrations (10−10 and 10−8 M) increased HA 3-fold. On the contrary, at a high concentration (10−6 M) ET-1 reduced HA by 47%. The ET-A receptor antagonist BQ123 not only reversed the reducing effect of high ET-1 on HA, but elevated it to the same level as low concentration ET-1, suggesting separate regulating roles for ET-A and ET-B receptors. This was corroborated by the addition of ET-B receptor antagonist BQ788 to low concentration ET-1, which abolished the HA increase. HAS2 and Hyal2 mRNA did not alter, while Hyal1 mRNA was increased at all ET-1 concentrations tested. Hyal activity was elevated the most by high ET-1 concentration, and blockade of ET-A receptors by BQ123 prevented about 30% of this response. The present study demonstrates an important regulatory influence of hormones involved in body fluid balance on HA handling by RMICs, thereby supporting the concept of a dynamic involvement of interstitial HA in renal fluid handling.