bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrical transport of an AlGaN/GaN two-dimensional electron gas
Authors: Saxler A. , Debray P. , Perrin R. , Elhamri S. , Mitchel W. C. , Elsass C.R. , Smorchkova I.P. , Heying B. , Haus E. , Fini P. , Ibbetson J.P. , Keller S. , Petroff P.M. , DenBaars S.P. , Mishra U.K. , Speck J.S.
Published: April 2019

An AlxGa1−xN/GaN two-dimensional electron gas structure with x = 0.13 deposited by molecular beam epitaxy on a GaN layer grown by organometallic vapor phase epitaxy on a sapphire substrate was characterized. Hall effect measurements gave a sheet electron concentration of 5.1×1012 cm−2 and a mobility of 1.9 × 104 cm2/Vs at 10 K. Mobility spectrum analysis showed single-carrier transport and negligible parallel conduction at low temperatures. The sheet carrier concentrations determined from Shubnikov-de Haas magnetoresistance oscillations were in good agreement with the Hall data. The electron effective mass was determined to be 0.215±0.006 m0 based on the temperature dependence of the amplitude of Shubnikov-de Haas oscillations. The quantum lifetime was about one-fifth of the transport lifetime of 2.3 × 10−12 s.
Correlation Between Sheet Carrier Density-Mobility Product and Persistent Photoconductivity in AlGaN/GaN Modulation Doped Heterostructures
Authors: Li J. Z. , Li J. , Lin J. Y. , Jiang H. X.
Published: April 2019

High quality Al0.25Ga0.75N/GaN modulation-doped heterojunction field-effect transistor (MOD-HFET) structures grown on sapphire substrates with high sheet carrier density and mobility products (nsμ > 1016/Vs at room temperature) have been grown by metal organic chemical vapor deposition (MOCVD). The optimized structures were achieved by varying structural parameters, including the AlGaN spacer layer thickness, the Si-doped AlGaN barrier layer thickness, the Si-doping concentration, and the growth pressure. In these structures, the persistent photoconductivity (PPC) effect associated with the two-dimensional electron gas (2DEG) system was invariantly observed. As a consequence, the characteristic parameters of the 2DEG were sensitive to light and the sensitivity was associated with permanent photoinduced increases in the 2DEG carrier mobility (μ) and sheet carrier density (ns). However, we observed that the magnitude of the PPC and hence the photoinduced instability associated with these heterostructures were a strong function of only one parameter, the product of ns and μ, which is the most important parameter for the HFET device design. For a fixed excitation photon dose, the ratio of the low temperature PPC to the dark conductivity level was observed to decrease from 200% to 3% as the nsμ (300 K) product was increased from 0.048 × 1016/Vs to 1.4 × 1016/Vs. Based on our studies, we suggest that the magnitude of the low temperature PPC can be used as a sensitive probe for monitoring the electronic quality of the AlGaN/GaN HFET structures.
Optical Spectroscopy of Ingan Epilayers in the Low Indium Composition Regime
Authors: Crawford M. H. , Han J. , Banas M. A. , Myers S. M. , Petersen G. A. , Figiel J. J.
Published: April 2019

Photoluminescence (PL) spectroscopy was carried out on a series of Si-doped bulk InGaN films in the low indium (In) composition regime. Room temperature PL showed a factor of 25 increase in integrated intensity as the In composition was increased from 0 to 0.07. Temperature dependent PL data was fit to an Arrhenius equation to reveal an increasing activation energy for thermal quenching of the PL intensity as the In composition is increased. Time resolved PL measurements revealed that only the sample with highest In (x=0.07) showed a strong spectral variation in decay time across the T=4K PL resonance, indicative of recombination from localized states at low temperatures. The decay times at room temperature were non-radiatively dominated for all films, and the room temperature (non-radiative) decay times increased with increasing In, from 50-230 psec for x=0-0.07. Our data demonstrate that non-radiative recombination is less effective with increasing In composition.
Picosecond Photoinduced Reflectivity Studies of GaN Prepared by Lateral Epitaxial Overgrowth
Authors: Wraback M. , Shen H. , Eiting C.J. , Carrano J.C. , Dupuis R.D.
Published: April 2019

The pump-probe technique has been used to perform room temperature studies of the photoinduced changes in the reflectivity ΔR associated with exciton and carrier dynamics in GaN prepared by lateral epitaxial overgrowth. For resonant excitation of cold excitons, the ΔR decay possesses a 720 ps component attributed to the free exciton lifetime in this high quality material. For electrons with small excess energy (< 50 meV), the strong increase in the ΔR decay rate with decreasing excitation density suggests that screening of the Coulomb interaction may play an important role in the processes of carrier relaxation and exciton formation. The faster decay times at a given carrier density observed for hot (> 100 meV) electron relaxation are attributed to electron-hole scattering in conjunction with the screened electron-LO phonon interaction.
The Effect of Nitrogen Ion Damage on the Optical and Electrical Properties of MBE GaN Grown on MOCVD GaN/sapphire Templates
Authors: Young Alexander P , Brillson Leonard J. , Naoi Yoshiki , Tu Charles W.
Published: April 2019

We have established a correlation between localized states responsible for mid-gap optical emission and film mobility of GaN grown under different nitrogen conditions. By imposing a deflector voltage at the tip of the plasma source, we varied the ion/neutral flux ratio to determine how N ions affect mid-gap luminescence and electrical mobility. Low energy electron-excited nanometer scale luminescence (LEEN) spectroscopy in ultrahigh vacuum (UHV) showed mid-gap emission intensities in the bulk that decreased in the ratio, 50 : 1.3 : 1 with increasing deflector voltage. Hall measurements indicated over a factor of two increase in mobility, and a factor of 8 decrease in residual charge density with increasing deflector voltage. The correlation of optical and electrical properties with a reduction in N ion flux suggests the primary role of native defects, such as N or Ga vacancies, in the mid-gap emissions.
High Density Plasma Damage Induced in n-GaN Schottky Diodes Using Cl2/Ar Discharges
Authors: Zhang A.P. , Dang G. , Ren F. , Cao X.A. , Cho H. , Lambers E.S. , Pearton S.J. , Shul R.J. , Zhang L. , Baca A.G. , Hickman R. , Van Hove J.M.
Published: April 2019

The effects of dc chuck self-bias and high density source power (which predominantly control ion energy and ion flux, respectively) on the electrical properties of n-GaN Schottky diodes exposed to Inductively Coupled Plasma of Cl2/Ar were examined. Both parameters were found to influence the diode performance, by reducing the reverse breakdown voltage and Schottky barrier height. All plasma conditions were found to produce a nitrogen-deficient surface, with a typical depth of the non-stoichiometry being ∼ 500 Å. Post-etch annealing was found to partially restore the diode characteristics.
Comparison of Implant Isolation Species for GaN Field-effect Transistor Structures
Authors: Dang G. , Cao X. A. , Ren F. , Pearton S. J. , Han J. , Baca A. G. , Shul R. J. , Wilson R. G.
Published: April 2019

Different ions (Ti+, O+, Fe+, Cr+) were implanted at multiple energies into GaN field effect transistor structures (n and p-type). The implantation was found to create deep states with energy levels in the range EC −0.20 to 0.49 eV in n-GaN and at EV +0.44 eV in p-GaN after annealing at 450-650 °C. The sheet resistance of the GaN was at a maximum after annealing at these temperatures, reaching values of ∼4×1012 Ω/□ in n-GaN and ∼1010 Ω/□ in p-GaN. The mechanism for the implant isolation was damage-related trap formation for all of the ions investigated, and there was no evidence of chemically induced isolation.
Oxidation of Gallium Nitride Epilayers in Dry Oxygen
Authors: Chen P. , Zhang R. , Xu X.F. , Chen Z.Z. , Zhou Y.G. , Xie S.Y. , Shi Y. , Shen B. , Gu S.L. , Huang Z.C. , Hu J. , Zheng Y.D.
Published: April 2019

The oxidation of GaN epilayers in dry oxygen has been studied. The 1-µm-thick GaN epilayers grown on (0001) sapphire substrates by Rapid-Thermal-Processing/Low Pressure Metalorganic Chemical Vapor Deposition were used in this work. The oxidation of GaN in dry oxygen was performed at various temperatures for different time. The oxide was identified as the monoclinic β-Ga2O3 by a θ−2θ scan X-ray diffraction (XRD). The scanning electron microscope observation shows a rough oxide surface and an expansion of the volume. XRD data also showed that the oxidation of GaN began to occur at 800°C. The GaN diffraction peaks disappeared at 1050°C for 4 h or at 1100°C for 1 h, which indicates that the GaN epilayers has been completely oxidized. From these results, it was found that the oxidation of GaN in dry oxygen was not layer-by-layer and limited by the interfacial reaction and diffusion mechanism at different temperatures.
A Thermodynamic Approach to Ohmic Contact Formation to p-GaN
Authors: Liu Bo , Ahonen Mikko H. , Holloway Paul H.
Published: April 2019

A new ohmic contact scheme for gallium nitride is presented. The use of Nitride-forming metal Over Gallide-forming metal, “NOG”, can modify the thermodynamic activity of N and Ga near the interface. This in turn can modify the near-surface point defect concentrations, particularly the vacancies of Ga and N. The principle of this contact scheme was shown to be consistent with results from Ni/Au, Ni/Zn-Au, Ta/Ti, and Ni/Mg/Ni/Si contacts. In the present study, the “NOG” scheme was used to design Ni/Ti/Au and Ni/Al/Au metallization, and addition of Ti and Al nitride-forming metals to the Ni gallide-forming metal led to lower but still high contact resistance. Ti was shown to be better than Al as the nitride-forming metal based on the decrease of resistance in as deposited contacts. Compared to Ni/Au, four times more current was measured in Ni/Ti/Au contacts to p-GaN after anneal at 300°C for 5min. However the addition of the Ti nitride-forming metal led to lower stability at 500°C.
Deep levels in n-type Schottky and p+-n homojunction GaN diodes
Authors: Hierro A. , Kwon D. , Ringel S. A. , Hansen M. , Mishra U. K. , DenBaars S. P. , Speck J. S.
Published: April 2019

The deep level spectra in both p+-n homojunction and n-type Schottky GaN diodes are studied by deep level transient spectroscopy (DLTS) in order to compare the role of the junction configuration on the defects found within the n-GaN layer. Both majority and minority carrier DLTS measurements are performed on the diodes allowing the observation of both electron and hole traps in n-GaN. An electron level at Ec−Et=0.58 and 0.62 V is observed in the p+-n and Schottky diodes, respectively, with a concentration of ∼3−4×1014 cm−3 and a capture cross section of ∼1−5×10−15 cm2. The similar Arrhenius behavior indicates that both emissions are related to the same defect. The shift in activation energy is correlated to the electric field enhanced-emission in the p+-n diode, where the junction barrier is much larger. The p+-n diode configuration allows the observation of a hole trap at Et−Ev=0.87 eV in the n-GaN which is very likely related to the yellow luminescence band.
Fermi Level Pinning at GaN-interfaces: Correlation of electrical admittance and transient spectroscopy
Authors: Witte H. , Krtschil A. , Lisker M. , Rudloff D. , Christen J. , Krost A. , Stutzmann M. , Scholz F.
Published: April 2019

In GaN layers grown by molecular beam epitaxy as well as metal organic vapor phase epitaxy significant differences were found in the appearance of deep defects detected by thermal admittance spectroscopy as compared for deep level transient spectroscopy measurements. While, thermal admittance spectroscopy measurements which were made under zero bias conditions only show thermal emissions at activation energies between 130 and 170 meV, further deep levels existing in these GaN layers were evidenced by transient spectrocopy. This discrepancy is explained by a pinning effect of the Fermi level at the metal / GaN interface induced by high a concentration of the deep levels showing up in thermal admittance spectroscopy. We compare our results with a GaAs:Te Schottky- diode as a refernec sample. Here, both spectroscopic methods give exactly the same deep level emissions.
Influence of Internal Electric Fields on the Ground Level Emission of GaN/AlGaN Multi-Quantum Wells
Authors: Bonfiglio A. , Lomascolo M. , Traetta G. , Cingolani R. , Di Carlo A. , Della Sala F. , Lugli P. , Botchkarev A. , Morkoc H.
Published: April 2019

The spectroscopic investigation of GaN/AlGaN quantum wells reveals that the emission energy of such structures is determined by four parameters, namely composition, well-width, strain and charge density. The experimental data obtained by varying these parameters are quantitatively explained by an analytic model based on the envelope function formalism which accounts for screening and built-in field, and by a full self-consistent tight-binding model.
Ukraina wobec wyzwań gospodarczych i politycznych
Authors: Rubaj Piotr , Voytsekhovska Viktoriya
Published: April 2019

The article presents the current economic and social situation of Ukraine and the possible scenarios for its future development. It seems that deep structural reforms, rapprochement with EU and ending the conflict in the Donbas are essential to improving Ukraine’s standard of living and sense of security. These processes are very complicated and render significant progress in the near term unlikely. The crisis in Ukraine has an important impact on neighbouring Poland, for which this publication reviews the potential economic and social implications.
Analiza wpływu utrzymania i zmian ocen ratingowych na wysokość spreadu kredytowego na przykładzie polskiego rynku obligacji przedsiębiorstw w latach 2010-2017
Authors: Orzechowski Arkadiusz
Published: April 2019

The purpose of the article is to determine the impact of maintaining and changing credit ratings formulated by the Moody’s rating agency on the credit spread on the Polish debt market in the period 2010–2017. It seeks to draw conclusions on the efficiency of the Polish debt market with respect factors including raising, maintaining at the current level or lowering the rating. The methodology used in the paper is based on the standard procedure for studying events. The results of the conducted research are not unequivocal. While they indicate a correct response of the credit spread to changes in the credit ratings, the results obtained are not confirmed by statistical significance tests.
Zastosowanie rachunku kosztów działań na przykładzie wybranego przedsiębiorstwa
Authors: Mokrzycka Katarzyna
Published: April 2019

Activity-based costing has become a very interesting and important issue. Still changing conditions and highly complicated production processes have rendered traditional accounting cost systems sometimes inadequate for making decisions. Managers are aware that they need cost accounting solutions that will quickly deliver them certain information. The aim of this article is to present the point of activity-based costing and to describe the principles of design and implementation of this costing method in Polish companies. It presents the results of research on the practical application of activity-based costing in an enterprise.
Ideał bycia sobą we wczesnych pracach Fryderyka Nietzschego (przyczynek do dyskusji nad koncepcją autentyczności Charlesa Taylora)
Authors: Kusak Leszek
Published: April 2019

In "The Ethics of Authenticity", Charles Taylor presents a critique of individualism which is dominating modernity. It is characterised by relativism, moral subjectivism and narcissism, and it results in the atomisation of social life. Friedrich Nietzsche is cast in the role of the spiritual father of these harmful phenomena, as – according to Taylor – he changed the respect-worthy ideal of authentic life into its opposite – egocentric self-realisation.Towards debating Taylor’s point of view, the article looks at the frequently overlooked fact that Nietzsche’s ideal of “being true to oneself” evolved over time and changed in the successive periods of his activity. In his youth (1869–1874), the author of "The Birth of Tragedy" argued for so-called intelligent egoism and being true to oneself, defined as self-realisation, which is aware of responsibility for the common good. The ideal of “being true to oneself” presented by the young Nietzsche therefore meets Taylor’s requirements of “true authenticity”.
Deklaracja społecznej odpowiedzialności uczelni jako wzmocnienie etosu akademickiego
Authors: Gałat Wioleta
Published: April 2019

On 16 November 2017, 23 Polish higher education institutions signed a CSR Declaration. The declaration includes twelve points stipulating the principles related to CSR in higher education. The reasons for the growing significance of the concept of CSR in higher education can be attributed to the diminishing importance of academic ethos. The values that constitute academic ethos should be a guiding light for activities undertaken by universities, so their diminishing significance is a cause for concern. Developing the concept of CSR in higher education is an opportunity to keep these values alive. The article explores the values common for academic ethos and CSR in the Higher Education Declaration. The analysis leads to the conclusion that the popularisation of the concept of CSR in higher education has been reinforced by the declaration, which largely refers to academic ethos.
Psychological Factors Affecting Purchasing Decisions on the Real Estate Market
Authors: Bartkowiak Piotr , Potrawiak Patrycja , Pavlenko Jury G.
Published: April 2019

The article discusses the identification and systematisation of factors which may affect purchase decisions on the real estate market, with a particular emphasis on behavioural factors. In the course of the conducted analysis, the decision-maker analyses factors related to real estate, but also psychological factors, among which the most significant are: motivations, emotions, attitudes, personality, learning, memory and perception. The work provides a review of the literature, seeking to identify factors that influence the decision making process on the real estate market.
Synthesis and performance of a series of novel low-molecular-weight superplasticisers with star-shaped phosphate frame
Authors: Qi Shuai , Wang Tao , Han Zheng , Fan Shimin , Ma Jianfeng , Yang Yong , Zheng Shuzhen , Ran Qianping
Published: April 2019

A new type of small-molecule phosphate superplasticiser (SP) was synthesised in one pot by the phosphorylation reaction of star-polyether with phosphoric acid. By varying the structure of the initiator polyamines, star-shaped small-molecule phosphate SPs with different molecular weights and anionic charge densities were prepared. The synthesised SPs were characterised by means of proton nuclear magnetic resonance, high-performance liquid chromatography, Fourier transform infrared spectroscopy and gel permeation chromatography. Their dispersion ability, adsorption behaviour and retardation effect on cement hydration were investigated. It was proved that the star-shaped small-molecule phosphate compounds with longer polyether chains and more phosphate groups could be successfully applied as anti-clay SPs. The findings provide useful information for optimising the performance of phosphated small-molecule chemical admixtures in the future.
Influence of low-impact development in flood control for a design rainfall event
Authors: Veról Aline Pires , Miguez Marcelo Gomes
Published: April 2019

Urbanisation modifies the natural hydrological cycle and aggravates floods. If the limits imposed by the natural environment are respected in the urban planning process, it is expected that the city resulting from this process will be able to coexist with floods, suffering minor damages. In this context, this work uses the concept of low-impact development (LID) to ‘go back in time’, with the aid of mathematical modelling tools, identifying an earlier moment of initial development of the city of Mesquita, in Brazil, to evaluate the flooding situation at that time and compare it with the current situation, seeking to understand how the worsening process of the urban floods evolved. Then, an alternative growth pattern is modelled from the past to the present, revising urban development guidelines to incorporate flood concerns and LID concepts. The main findings indicate that flood flows need space; the bottom of the valleys and the riverine areas should be preserved as open spaces to accommodate floods, and LID can help in preventing floods, but the excess of imperviousness is critical and very difficult to reverse.
Cine-Poema: a poesia de Sophia de Mello Breyner Andresen no filme de João César Monteiro
Authors: Pereira Ana Catarina
Published: April 2019

Resumo: “O poeta é levado a buscar a justiça.” As palavras de Sophia de Mello Breyner, pronunciadas no documentário com que João César Monteiro inicia a sua filmografia, revelam a responsabilidade social com que ambos os artistas – cineasta e poetisa – encararam o percurso e posições públicas assumidas, ainda que em estilos claramente distintos. Sophia, filme que ocupa um lugar de destaque no Novo Cinema Português e que vem dar nome aos Prémios da Academia Portuguesa de Cinema, é a obra em análise no presente artigo. Reflectindo sobre o diálogo estabelecido entre os dois lados da câmara e a assumida vontade do realizador em buscar uma essência do Cinema, tentaremos identificar o modo como o espaço é filmado, na sua relação com a personagem e com o tipo de documentário resultante. Palavras-chave: Sophia, Hans Gumbrecht, presença, espaço.Abstract: “The poet is brought to seek justice.” The words of Sophia de Mello Breyner, pronounced in the documentary with which João César Monteiro begins his filmography, reveal the social responsibility with which both artists – the filmmaker and the poet - faced the course and assumed public positions, even though in distinctly different styles. Sophia, a film that occupies a prominent place in the New Portuguese Cinema and that is now used by the Prizes of the Portuguese Film Academy, is the work in analysis in the present article. Reflecting on the dialogue established between the two sides of the camera and the director’s willingness to pursue an essence of cinema, we will try to identify the way space is filmed, its relationship to the character and the type of documentary that comes up.Keywords: Sophia, Hans Gumbrecht, presence, space.
QUINTAIS, Luís. A noite imóvel. Porto: Assírio & Alvim, 2017. 181p.
Authors: Cantalice Paulo Victor
Published: April 2019

QUINTAIS, Luís. A noite imóvel. Porto: Assírio & Alvim, 2017. 181p.
A cidade moderna contada por Sophia de Mello Breyner Andresen
Authors: Menezes Carlos Roberto Dos Santos
Published: April 2019

Resumo: A partir das considerações de Eduardo do Prado Coelho em “Sophia, a lírica e a lógica” (1980); Sofia de Sousa Silva, “Sobre a paisagem em Sophia de Mello Breyner Andresen”; Helena Carvalhão Buescu, Cristalizações: fronteiras da modernidade (2005), entre outros, o presente texto busca compreender como a imagem da cidade contemporânea é representada na escrita de Sophia de Mello Breyner Andresen como forma de intervenção crítica sobre uma realidade hostil, cruel e indiferente. Partindo da leitura do conto “O homem”, extraído do livro Contos exemplares, pretendemos averiguar de que modo a sociabilidade sofre degeneração no espaço urbano e quais são os meios de resgatar a humanidade aparentemente perdida pelas paredes da cidade.Palavras-chave: Sophia de Mello Breyner Andresen; cidade; O homem; Contos exemplares; injustiça.Abstract: From the considerations of Eduardo do Prado Coelho in “Sophia, a lírica e a lógica” (1980); Sofia de Sousa Silva, “Sobre a paisagem em Sophia de Mello Breyner Andresen”; Helena Carvalhão Buescu, Cristalizações: fronteiras da modernidade (2005), among others, this text seeks to understand how the image of the contemporary city is represented in the writing of Sophia de Mello Breyner Andresen as a form of critical intervention over a hostile, cruel and indifferent reality. Starting from the reading of the short story “O homem”, extracted from the book Contos exemplares, we intend to find out how sociability suffers degeneration in urban space and what are the means of rescuing the humanity apparently lost by the walls of the city.Keywords: Sophia de Mello Breyner Andresen; city; O homem; Contos exemplares; injustice.
Os sentidos da revelação: Sophia e Herberto
Authors: Sousa Paulo Ricardo Braz de
Published: April 2019

Resumo: Este ensaio busca investigar os sentidos da revelação poética nas obras de Sophia de Mello Breyner Andresen e Herberto Helder. Para tanto, é utilizado (principalmente, mas não apenas) um arcabouço teórico que atravessa as concepções filosóficas de Friedrich Nietzsche em torno da questão estética entre uma arte apolínea e outra dionisíaca, assim como suas intersecções. A partir de um exercício de leitura corpo a corpo dos poemas selecionados de ambos os autores, a ideia deste trabalho é reconhecer como estas distintas poéticas, cada qual ao seu modo, manifesta íntimas relações com a experiência do sagrado. Por fim, este ensaio projeta a possibilidade de fazer do procedimento crítico aqui desenvolvido um modo de leitura da moderna poesia portuguesa.Palavras-chave: Sophia de Mello Breyner Andresen; Herberto Helder; revelação poética; sagrado.Abstract: This essay tries to investigate the senses of poetic revelation in the works of Sophia de Mello Breyner Andresen and Herberto Helder. For that, a theoretical framework is used (mainly, but not only) that crosses the philosophical conceptions of Friedrich Nietzsche about the aesthetic question between an Apollonian and a Dionysian art, as well as its intersections. From an close reading exercise of the selected poems of both authors, the idea of this work is to recognize how these different poetics, each in its own way, manifests intimate relationships with the experience of the sacred. Finally, this article plans the possibility of making this critical procedure a way of reading modern Portuguese poetry.Keywords: Sophia de Mello Breyner Anresen; Herberto Helder; poetic revelation; sacred.
Evaluation of solitary thyroid nodule by clinical presentation, fine needle aspiration cytology and thyroid scan
Authors: Surriah Mohammed Hillu , Bakkour Amine Mohammed , Jallod Al-Asadi Riad Rahman , Majeed Laith Qauis
Published: April 2019

Background: The solitary thyroid nodule, defined as a palpable discrete swelling within an otherwise apparently normal gland, is usually a benign lesion. However, patients and physicians alike are typically concerned about the possibility of thyroid cancer. This study describes a strategy for the treatment of clinically euthyroid patients who have a solitary thyroid nodule that prevents unnecessary testing while identifying the few patients who require therapy.Methods: This is a prospective study of randomly selected patients with clinically palpable, solitary thyroid nodule diagnosed and treated at Al-Karama Teaching Hospital from September 2015 till December 2018. Initially 176 patients were diagnosed by clinical examination to have solitary thyroid nodule but after investigation and operative finding, 42 patients were found to have multinodular goiter and all excluded from the study.Results: All the 134 patients included in the study (21 males and 113 females) have been evaluated by clinical examination; thyroid scan and fine needle aspiration, ultrasound and the results of the evaluation have been correlated with operative histologic diagnosis. The study was undertaken to obtain information on the usefulness of the above measures for predicting or ruling out malignancy in solitary thyroid nodule.Conclusions: The incidence of malignancy seems to be higher among male, presented with hard nodule at palpation, those associated with hoarseness or palpable cervical lymph nodes. A cytological diagnosis of malignant tumor is reliable and provides sufficient basis of definitive surgery for thyroid cancer.
Generalized Fréchet Bounds for Cell Entries in Multidimensional Contingency Tables
Authors: Uhler Caroline , Richards Donald
Published: April 2019

We consider the lattice, $\mathcal{L}$, of all subsets of a multidimensional contingency table and establish the properties of monotonicity and supermodularity for the marginalization function, $n(\cdot)$, on $\mathcal{L}$.  We derive from the supermodularity of $n(\cdot)$ some generalized Fr\'echet inequalities complementing and extending inequalities of Dobra and Fienberg.  Further, we construct new monotonic and supermodular functions from $n(\cdot)$, and we remark on the connection between supermodularity and some correlation inequalities for probability distributions on lattices.  We also apply an inequality of Ky Fan to derive a new approach to Fr\'echet inequalities for multidimensional contingency tables.
Cubature rules and expected value of some complex functions
Authors: Fassino Claudia , Riccomagno Eva , Rogantin Maria Piera
Published: April 2019

The expected value of some complex valued random vectors is computed by means of the indicator function of a designed experiment as known in algebraic statistics. The general theory is set-up and results are obtained for nite discrete random vectors and the Gaussian random vector. The precision space of some cubature rules/designed experiments are determined.
ОСОБЕННОСТИ ОКИСЛИТЕЛЬНОГО ОБЕССЕРИВАНИЯ ВАКУУМНОГО ГАЗОЙЛЯ
Authors: (Yulia A. Iovik) Иовик Юлия Александровна , (Evgeniy B. Krivtsov) Кривцов Евгений Борисович , (Anatoliy K. Golovko) Головко Анатолий Кузьмич
Published: April 2019

Актуальность исследования обусловлена необходимостью поиска более дешевых чем гидроочистка методов переработки вакуумного газойля. Цель работы: установление концентрационных зависимостей окисления серосодержащих компонентов вакуумного газойля. Объект: вакуумный газойль Новокуйбышевского НПЗ. Методы: окисление, жидкостно-адсорбционная хроматография, тонкослойная хроматография, рентгенофлуорецентное определение содержания серы, вещественный анализ. Результаты. Установлены оптимальные условия окисления вакуумного газойля Новокуйбышевского НПЗ: продолжительность 90 мин, мольное соотношение So:H2O2=1:5, скорость перемешивания 2500 об/мин. Наибольшая эффективность адсорбционной очистки от продуктов окисления сераорганических соединений достигается при массовом соотношении «силикагель: объект исследования»=1:1. Выявлено влияние количества окислителя и продолжительности процесса на выход продуктов окислительного обессеривания и содержание серы в них. Установлены закономерности окисления серосодержащих соединений вакуумного газойля: увеличение продолжительности окисления и мольного соотношения So:H2O2 не влияет на содержание насыщенных соединений; выходы моно- и биароматических соединений, содержание серы в них линейно снижаются. При продолжительности окисления 30 мин с увеличением мольного соотношения So:H2O2 увеличивается выход и содержание серы в три- и полиароматических соединениях вследствие накопления неадсорбированных продуктов окисления моно- и биароматических серосодержащих соединений. Увеличение продолжительности процесса приводит к развитию побочных реакций окисления моно- и биароматических углеводородов, продукты окисления которых выделяются в составе полиароматических углеводородов. Окисленные серосодержащие соединения в этих условиях выделяются в составе смол. Изменение содержания асфальтенов незначительно.
Utilidad de la angiografía pulmonar por tomografía computarizada en las salas de emergencia de un hospital nacional de EsSalud
Authors: Román Meza Alexander , Alfaro Fernández Paul
Published: April 2019

Objetivos: Determinar la utilidad de la angiografía pulmonar por tomografía computarizada en Emergencia en un Hospital Nacional de EsSalud. Material y métodos: Estudio descriptivo, cuantitativo, retrospectivo y transversal. La población estuvo constituida por 77 pacientes. La unidad de análisis fue el paciente atendido por Emergencia a quien se realizó angiografía pulmonar por tomografía computarizada. La recolección se realizó mediante una ficha de registro de datos. Resultados: Del total, 64,9% fueron adultos mayores, 63,6% de género masculino, y sólo 31,2% tuvo presunción diagnóstica específica, dada por la sospecha de tromboembolismo pulmonar. Sólo hubo hallazgos patológicos en 29,9% de casos, donde la mayoría fue tromboembolismo pulmonar, con 65,2%, mientras que en los restantes fue hipertensión pulmonar. En los exámenes con presunción específica el 50% fue normal, mientras que en los casos con presunción inespecífica el 79.2% fue normal; esta diferencia fue estadísticamente significativa (p=0,019 con chi cuadrado corregido y p=0,014 con prueba exacta de Fisher). Conclusiones: La angiografía pulmonar por tomografía computarizada permite obtener hallazgos patológicos con presunción específica.
Giant pneumatization of sphenoid sinus: Report of four cases and review of literature
Authors: Kusch Anne Marie , Ruiz García Vilma
Published: April 2019

El hueso esfenoidal ocupa la mayor parte de la zona anterior de la fosa craneal media, está compuesto por un cuerpo, dos pares de alas (mayores y menores) las que se proyectan lateralmente desde el cuerpo, y dos procesos pterigoideos proyectados inferior y lateralmente de las coanas. Este hueso representa el límite entre la fosa craneal anterior y media. Usualmente, el seno esfenoidal se encuentra ubicado en su cuerpo, el cual presenta una gran variación en su neumatización, variando desde ausente hasta extenso. Puede extenderse a distintas partes del hueso esfenoidal e inclusive a estructuras óseas cercanas. Su localización profunda hace difícil el diagnóstico mediante radiografías, especialmente cuando se utilizan técnicas convencionales. Se presentan cuatro casos de neumatización gigante del seno esfenoidal observados como hallazgo imagenológico.
Conceptos de aceptación y adaptación en discapacidades mayores
Authors: Reátegui-Vargas Pedro Enrique , Neciosup-Tomé Verónica D.
Published: April 2019

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Alta frecuencia del dolor de espalda en los escolares
Authors: Santos-Cueva Nelly
Published: April 2019

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¿El retraso en el diagnóstico de la parálisis cerebral infantil genera mayores consecuencias en el desarrollo psicomotor?
Authors: Ruiz-Pingo Roxana Leonor
Published: April 2019

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Factores asociados a irritabilidad en adultos con episodio depresivo en Lima Metropolitana
Authors: Salazar-Saavedra Yesenia M. , Saavedra-Castillo Javier E.
Published: April 2019

Objetivo: Determinar factores sociodemográficos y clínicos asociados a la presencia de irritabilidad en adultos con episodio depresivo (ED) en Lima Metropolitana. Materiales y Métodos: Estudio observacional, correlacional, transversal, utilizando la base de datos de adultos desde los 18 años del Estudio Epidemiológico de Salud Mental de Lima Metropolitana y Callao del año 2012, en una muestra probabilística multietápica de 4445 adultos. Los instrumentos usados fueron una ficha de datos sociodemográficos, MINI (Entrevista Neuropsiquiátrica Internacional), Cuestionario de Salud Mental de Colombia (modificado), Índice de Calidad de Sueño de Pittsburgh, EMBU modificado y Cuestionario de Experiencias Tempranas Adversas. Se utilizó estadística descriptiva, regresión simple y multivariada para estimar la prevalencia de adultos con irritabilidad en episodio depresivo (IED) y determinar la asociación entre IED y variables independientes. Resultados: La prevalencia de IED fue de 34,9%. Se halló asociación estadísticamente significativa con: menor edad de inicio del ED, mayor severidad del ED, presencia de trastorno de ansiedad generalizada, abuso/dependencia de alcohol, algunos síntomas depresivos (autorreproches, problemas de concentración e indicadores suicidas), conductas violentas, menor calidad de sueño, estilos de crianza de sobreprotección y favoritismo, y presencia de eventos adversos antes de los 18 años. Conclusiones: Varias características y factores diferencian la depresión con irritabilidad de la que carece de este síntoma. La posibilidad de que la irritabilidad llegue a ser considerada como un especificador del episodio depresivo, contribuiría a desarrollar estrategias para su más precisa identificación y manejo clínico.
Síndrome de Capgras: una revisión breve
Authors: Strobbe-Barbat Mariella , Macedo-Orrego Luis , Cruzado Lizardo
Published: April 2019

Los  síndromes  de  falsa  identificación, grupo  de  patologías  neuropsiquiátricas,  con  las  delusiones  de  falso reconocimiento como denominador común, incluyen, entre otros, al  Síndrome de Capgras, caracterizado por la firme creencia, por parte del paciente, de que una persona cercana a él/ella, generalmente un familiar, ha sido sustituida por un “doble exacto” o “impostor”, describiendo la similitud física entre ambos; en pocos casos, tal creencia se extiende a  animales domésticos e incluso a objetos inanimados. Un alto porcentaje de casos se asocia a un trastorno orgánico cerebral de base, especialmente demencias neurodegenerativas, pero también puede ocurrir en enfermedades psiquiátricas primarias, tales como esquizofrenia y trastornos esquizoafectivos o afectivos. La exploración neurobiológica plantea diferentes hipótesis explicativas del síndrome, entre ellas los modelos de desconexión visuoanatómico de Ellis y Young, de lateralización de Gainotti y de distribución de redes neuronales de Gobbini y Haxby. El falso reconocimiento puede dar lugar a conductas violentas del paciente contra las personas implicadas como supuestos “dobles”, especialmente en casos de pacientes varones, con enfermedad psiquiátrica de fondo (i.e., esquizofrenia paranoide), con antecedentes de consumo de sustancias psicoactivas o presencia concomitante de alucinaciones auditivas imperativas. No existe tratamiento específico para el Síndrome de Capgras, pero ciertamente el cuadro psiquiátrico subyacente debe ser manejado con fármacos antipsicóticos e incluso terapia electroconvulsiva.
Strategy for Supply Chain Integration of Autonomous Electrical Vehicles in the Internet of Things
Authors: Radanliev Petar
Published: April 2019

This paper outlines a new methodology for developing strategy for supply chain integration of Autonomous Electrical Vehicles (AEV) to the Internet of Things (IoT). The methodology consists of external architecture and internal design that anticipates the business strategy in the development process. The methodology is designed to anticipate the impact of developments in new road transport technologies, such as Tesla Truck or Tesla Pickup. Since the methodology is designed to anticipate the impact of non-existing technologies, it represents green-field analysis. Green-field is defined as a new and non-existent operation. Green-field strategy architecture in this paper is presented as a process of accepting the world and acting upon that version of the world. The results of the analysis are presented as pathways and outcomes, emerging from the interrelated relationship between AEV and IoT. The emerging methodology is applied through two case studies to evaluate the impact to environment, performance and operationalisation. The methodology proposes architecture and design for integrating AEV and IoT in the supply chain strategy, and a set of new evaluation criteria that promote acceptance of Artificial Intelligence (AI) in the design process. The main contribution to knowledge is a new methodology for integrating AEV and the IoT to the supply chains. The paper applies interplay between inductive and deductive case study and grounded theory approach to build upon the concept of supply chain architecture and contribute to knowledge to the topic of formulating green-field integrated AEV- IoT supply chain strategy.
Folhas de ébano: (auto) biografias de escravizados e ensino de história
Authors: Da Silva Alexandra Lima
Published: April 2019

Este trabalho procura indicar a importância do uso de autobiografias de escravizados no ensino de História, para o qual a compreensão da dimensão educativa das biografias não é novidade. Desde finais do século XIX, livros didáticos de História do Brasil exploram as histórias de vida de personagens considerados célebres, no sentido de fomentar a consciência de nação a partir da exemplaridade dos feitos e fatos dos ditos grandes homens. O processo de renovação da historiografia vem promovendo mudanças, principalmente no entendimento dos escravizados como sujeitos ativos e complexos, dotados de culturas, experiências e saberes. O presente artigo defende que as autobiografias são um caminho para a compreensão dos escravizados como protagonistas e sujeitos da própria história, na luta pela liberdade e pela igualdade.
Efeito da embalagem com atmosfera modificada na conservação do Brycon amazonicus
Authors: VIANA Adriana Pontes , INHAMUNS Antônio José , OLIVEIRA Pedro Roberto de , SOUZA Laíza Caroline Lobo de
Published: April 2019

O matrinxã é muito apreciado na região amazônica, desta forma o aumento no tempo de vida útil comercial é fundamental. O objetivo deste trabalho foi avaliar a influência da Embalagem em Atmosfera Modificada í  EAM, associada í­Â  refrigeração para prolongar o tempo de armazenamento do matrinxã, Brycon amazonicus sob 2Â±1Â°C. As amostras embaladas em EAM com CO2 (100%); CO2/N2 (60/40%) e vácuo tiveram suas caracterí­­sticas fí­­sico-quí­­micas, microbiológicas e sensoriais avaliadas durante 35 dias de armazenamento. As amostras embaladas a vácuo apresentaram maior crescimento microbiano, mas mantiveram boa qualidade por aproximadamente, 17 dias de estocagem. As amostras tratadas com EAM CO2/N2 (60/40%) e CO2(100%) apresentaram boa qualidade por aproximadamente, 35 dias. O teste de aceitabilidade do produto cozido foi igual para os atributos sabor, odor e textura, exceto para aparência e cor, que foram melhores, com significí­¢ncia de 5%, nos tratamentos CO2/N2 (60/40%) e vácuo. O presente estudo mostrou que o tratamento em atmosfera modificada CO2/N2(60/40%) se destacou aos demais tratamentos sendo uma técnica promissora para estender a vida útil do matrinxã por até 35 dias sob refrigeração.
THE REDESIGNING STRATEGY OF JEBRES MARKET FOR HERITAGE TOURISM WITH CONTEXTUAL ARCHITECTURAL APPROACH
Authors: Permata Sari Yuanita Nur , Purwani Ofita , Hardiyati Hardiyati
Published: April 2019

This paper focuses on the redesign of Jebres Market, Surakarta. The market is redesigned to meet the national standard and to fit the condition in which the nearby Solo Jebres Station Area is changed into heritage tourism area by municipal government. In this case, the market is changed into Tourism Market due to the municipal plan to turn the nearby Solo Jebres Station Area into a heritage tourism area.

The plan for the redesign of Jebres Market includes addition of capacity of users, the development of supporting facilities such as parking area, an addition of public area, and also other facilities. As the Solo Jebres Station is a heritage building, the redesign of Jebres Market as the supporting facility for the Station uses contextual architectural approach as mentioned by Brent C. Brolin in Architecture in Context (1980). This is done by adjusting the architectural elements of the architecture of Solo Jebres Station building to be applied to the new Tourism Market. Following Brolin’s theory, the elements applied to the new Market are the proportion of windows, exits and entrances, driveways, building material surfaces, finishing, and textures, parks, and architectural styles in buildings.
MODERN ARCHITECTURE APPLICATION ON WEDDING CENTRE DESIGN IN SURAKARTA
Authors: Thalia Ivana , Suastika Made , Pramesti Leny
Published: April 2019

Modern architecture is an approach in the field of architectural engineering that is used as a design approach. The research is done to discuss the field of architectural engineering, especially in planning and design. The purpose of this research is to reveal the concept of planning and design on the application of modern architecture as a design method in Wedding Center building in Surakarta. The method used is a descriptive explorative method on the preparation of planning and modern architecture design methods on the building design. Modern architectural design method is used as a method of design approach on building Wedding Center in Surakarta in order to be able to provide a building image in accordance with the concept of Wedding Center building as a one-stop wedding service in Surakarta. The results and discussion of analysis in this research are qualitative analysis. The final concept formed from this research is a conceptual model and the physical design model of Wedding Center with Modern Architecture Approaches in Surakarta.
CO-WORKING SPACE AS A CREATIVE-COLLABORATIVE SPACE OF COMMUNITY CENTRE IN PURWOKERTO
Authors: Indah Leny , Purwani Ofita , Pramesti Leny
Published: April 2019

This paper concerns about Designing Community Centre in Purwokerto as Creative-Collaborative space by using co-working space. Co-working space is one way to induce creative ideas, because it makes it possible for people to share and learn together with other people from different background. This space also anables people to connect and collaborate to create ideas.

As Purwokerto is one of the cities in Indonesia whose concern about developing its creative communities, this city has a potential to be the locus for the Community Centre. This article will then focus on the designing of the Community Centre by using co-working space for inducing creative and collaborative activities in Purwokerto. Some key aspects of co-working space to be applied in the design are the services, spatial layout and ambience of space.
LIGHTING DESIGN IMPROVEMENT FOR ENHANCING INDOOR VISUAL QUALITY OF GPIB IMMANUEL CHURCH MALANG
Authors: Dinapradipta Asri
Published: April 2019

Lighting affects how people feel, react, and function in various settings, therefore lighting design strategy for worship room at churches should be aimed not only at fulfil the standard visual performance but should also be set as to enrich the room’s perception i.e. as the God’s holy place as well as a place for contemplation. Lighting problems found at the worship room of GPIB Immanuel Malang are not merely on the inappropriateness of lighting level and distributions, but also on the absence of the church’ nuance as a place for contemplation. This paper is intended to report a proposed schematic lighting design for improving the situation. Using visual hierarchical approach, the lighting design aspects such as intensity, colour rendering, type, direction and arrangement of luminaires are determined and integrated. The proposed lighting design strategy is expected to be able to solve luminous problems and create the designated room’s nuance/perceptions.
THE TOURISM ELEMENT PRODUCT DEVELOPMENT OF SEMARANG OLD CITY BASED ON ATTRACTIVE URBAN HERITAGE APPROACH
Authors: Meytasari Cinthyaningtyas , Tisnawati Endah
Published: April 2019

The Old Town Semarang is a historical asset of the former Dutch East Indies colonial that is rich in tourism and science potential. The Old Town Semarang as a historical tourist attraction, divided into aspects of products, physical environment and the driving force of tourism elements. Each aspect has been possessed by The Old Town Semarang, but needs development in order to realize the Old Town Semarang as study center and attractive urban heritage tourism through the development of heritage products, and supported by elements of driving elements of tourism, such as government, private and community, through product studies and the driving force tourism, so that the Old Town Semarang can play a role in science regional tourism, even national, with the needs, tour / tour guides, and community, against the Old Town Semarang. Although in fact there are several inhibiting factors in realizing the Old City of Semarang as a historical tourist attraction.