bluuebunny/crossref_metadata_2025 huggingface dataset:
Totally Conservative Integration Method for the General Three-body Problem and Its Lagrangian Solutions
Authors: Minesaki Yukitaka
Published: February 2019

In this paper, we design a precise integration method with a variable time step for the general three-body problem that maintains all the conserved quantities. Our method is based on a logarithmic Hamiltonian leapfrog with chain vectors proposed by Mikkola & Tanikawa and features an energy-preserving parameter. Although the proposed method is merely second-order accurate, it can precisely trace some periodic orbits. This is not possible with generic geometric eighth-order numerical integrators and the logarithmic Hamiltonian leapfrog approach. Further, similar to logarithmic Hamiltonian leapfrog, our method is analytically shown to have Lagrangian solutions. Prior to the presented integration method, no integration method was known to preserve  all the conserved quantities, in addition to presenting triangular Lagrangian solutions. Because our method is implicit, it requires an iteration method. Therefore, the proposed approach seems to be computationally intensive. However, our method is less computationally burdensome than a generic explicit eighth-order symplectic method.
A Fokker–Planck Framework for Studying the Diffusion of Radio Burst Waves in the Solar Corona
Authors: Bian N. H. , Emslie A. G. , Kontar E. P.
Published: March 2019

Electromagnetic wave scattering off density inhomogeneities in the solar corona is an important process that determines both the apparent source size and the time profile of radio bursts observed at 1 au. Here we model the scattering process using a Fokker–Planck equation and apply this formalism to several regimes of interest. In the first regime the density fluctuations are considered quasi-static and diffusion in wavevector space is dominated by angular diffusion on the surface of a constant energy sphere. In the small-angle (“pencil-beam”) approximation, this diffusion further occurs over a small solid angle in wavevector space. The second regime corresponds to a much later time, by which scattering has rendered the photon distribution near-isotropic, resulting in a spatial diffusion of the radiation. The third regime involves time-dependent fluctuations and, therefore, Fermi acceleration of photons. Combined, these results provide a comprehensive theoretical framework within which to understand several important features of propagation of radio burst waves in the solar corona: emitted photons are accelerated in a relatively small inner region and then diffuse outward to larger distances. En route, angular diffusion results both in source sizes that are substantially larger than the intrinsic source and in observed intensity-versus-time profiles that are asymmetric, with a sharp rise and an exponential decay. Both of these features are consistent with observations of solar radio bursts.
MicroRNA-mediated Regulation of Mucin-type O-glycosylation Pathway: A Putative Mechanism of Salivary Gland Dysfunction in Sjögren Syndrome
Authors: Gallo Alessia , Vella Serena , Tuzzolino Fabio , Cuscino Nicola , Cecchettini Antonella , Ferro Francesco , Mosca Marta , Alevizos Ilias , Bombardieri Stefano , Conaldi Pier Giulio , Baldini Chiara
Published: March 2019

Objective.

To investigate microRNA (miRNA) that is potentially implicated in primary Sjögren syndrome (pSS)–related salivary hypofunction in labial salivary glands and to study miRNA-mediated mechanisms underlying oral dryness and altered rheology, focusing on the mucin O-glycosylation pathway.

Methods.

We performed miRNA expression profiling in minor salivary gland samples of patients with pSS presenting a different impairment in their unstimulated salivary flow rate. A computational in silico analysis was performed to identify genes and pathways that might be modulated by the deregulated miRNA that we had identified. To confirm in silico analysis, expression levels of genes encoding for glycosyltransferases and glycan-processing enzymes were investigated using Human Glycosylation-RT2 Profiler PCR Array.

Results.

Among 754 miRNA analyzed, we identified 126 miRNA that were significantly deregulated in pSS compared to controls, with a trend that was inversely proportional with the impairment of salivary flow rates. An in silico approach pinpointed that several upregulated miRNA in patients with pSS target important genes in the mucin O-glycosylation. We confirmed this prediction by quantitative real-time PCR, highlighting the downregulation of some glycosyltransferase and glycosidase genes in pSS samples compared to controls, such as GALNT1, responsible for mucin-7 glycosylation.

Conclusion.

Collectively, our data suggest that the expression of different predicted miRNA-target genes in the mucin type O-glycan biosynthesis pathway is altered in pSS patients with low salivary flow and that the miRNA expression profile could influence the glycosidase expression levels and consequently the rheology in pSS.
Burden and Disease Characteristics of Patients with Psoriatic Arthritis: A Population-based Cross-sectional Study
Authors: Tekin Hasan G. , Wu Jashin J. , Burge Russel , Birt Julie , Egeberg Alexander
Published: March 2019

Objective.

To describe the prevalence and treatment regimes, disease characteristics, and comorbid diseases among patients with psoriatic arthritis (PsA) in Denmark.

Methods.

All Danish individuals aged ≥ 18 years with rheumatologist-diagnosed PsA were linked in nationwide administrative registers.

Results.

Among 4.7 million individuals in Denmark, 10,577 patients with PsA had been diagnosed by a rheumatologist. A female predominance (54.5–59.8%) was seen among patients with PsA, and about half of the patients (53.0%) had received no treatment or treatment only with nonsteroidal antiinflammatory drugs/systemic corticosteroids, while 32.9% had received nonbiological disease-modifying antirheumatic drugs (DMARD) and 14.1% had been treated with biologicals. Cutaneous psoriasis was recorded in 66.2–72.3% of patients with PsA, and patients with severe PsA had the highest prevalences of distal interphalangeal arthropathy, spondylitis, and arthritis mutilans. Smoking and comorbid diseases such as hypertension, diabetes, depression, and anxiety were seen frequently in patients with PsA, but did not significantly differ across severities of PsA.

Conclusion.

Disease burden appeared to be significant in patients with PsA across all severities. A considerable proportion of patients with PsA did not receive active antipsoriatic treatment, and about 1 out of 3 patients was not diagnosed with psoriasis. Cutaneous symptoms of psoriasis in patients with PsA might be either underreported or undertreated.
HLA-DRB1 Haplotypes, Shared Epitope, and Disease Outcomes in US Veterans with Rheumatoid Arthritis
Authors: Zhao Ming , Mauer Lilli , Sayles Harlan , Cannon Grant W. , Reimold Andreas , Kerr Gail S. , Baker Joshua F. , Thiele Geoffrey M. , England Bryant R. , Mikuls Ted R.
Published: March 2019

Objective.

To evaluate associations of HLA-DRB1 haplotypes and shared epitope (SE) with rheumatoid arthritis (RA) severity and all-cause mortality in RA.

Methods.

Patients with RA from the Veterans Affairs Rheumatoid Arthritis (VARA) registry were followed from enrollment until death or December 31, 2013. Clinical characteristics, DNA, and serum were collected at enrollment. Radiographic damage, the presence or absence of subcutaneous nodules, disease activity measures, and functional status were assessed at enrollment and updated during followup. Sixteen HLA-DRB1 haplotypes and SE status were determined from banked DNA. Associations between HLA-DRB1 haplotypes, RA disease characteristics, and mortality were assessed in multivariable regression models.

Results.

Within VARA, 1443 participants had genotyping and accrued 6150 patient-years of followup. Haplotypes VKA, VRA, LRA, SRA, SRE, SKR, and SEA, and SE alleles were significantly associated with seropositivity for rheumatoid factor (RF) and/or anticyclic citrullinated peptide (anti-CCP). Haplotypes VKA and SKR were associated with higher RF concentrations, while VRA, DRE, and GRQ were associated with lower RF concentrations. Haplotypes VKA, VRA, and LRA were associated with higher concentrations of anti-CCP antibody, while haplotypes SRA, SRE, LEA, SKR, and SEA were significantly associated with lower anti-CCP concentrations. Haplotype VKA (OR 1.39, 95% CI 1.08–1.80) was associated with increased frequency of radiographic damage at enrollment but none of the haplotypes were associated with the presence of subcutaneous nodules. Haplotypes SKA (HR 1.52, 95% CI 1.26–1.83) was associated with higher mortality.

Conclusion.

HLA-DRB1 haplotypes are independently and variably associated with seropositivity, autoantibody concentrations, and outcomes in RA.
Factors Influencing Raynaud Condition Score Diary Outcomes in Systemic Sclerosis
Authors: Pauling John D. , Reilly Elizabeth , Smith Theresa , Frech Tracy M.
Published: March 2019

Objective.

Raynaud phenomenon (RP) in systemic sclerosis (SSc) could be influenced by clinical phenotype, environmental factors (e.g., season), and personal factors (e.g., coping strategies and ill-health perceptions). We studied the relative influence of a range of putative factors affecting patient-reported assessment of SSc-RP severity.

Methods.

SSc patients were enrolled at UK and US sites. Participants completed the 2-week Raynaud Condition Score (RCS) diary alongside collection of patient demographics, clinical phenotype, the Coping Strategies Questionnaire, Pain Catastrophizing Scale, Scleroderma Health Assessment Questionnaire (SHAQ), and both patient/physician visual analog scale (VAS) assessments for RP, digital ulcer disease, and global disease. Environmental temperature data were obtained at each site. A second RCS diary was completed 6 months after enrollment.

Results.

We enrolled 107 patients (baseline questionnaires returned by 94). There were significant associations between RCS diary variables and both catastrophizing and coping strategies. There were significant associations between RCS diary outcomes and both environmental temperature and season of enrollment. Age, disease duration, sex, disease subtype, smoking, and vasodilator use were not associated with RCS diary outcomes. The best-fitting multivariate model identified the patient RP VAS, SHAQ pain VAS, and SHAQ gastrointestinal VAS subscales as the strongest independent predictors of the RCS.

Conclusion.

Patient-reported assessment of SSc-RP severity is associated with a number of factors including pain, catastrophizing, and coping strategies. The effects of seasonal variation in environmental temperature on SSc-RP burden has implications for clinical trial design. Treatments targeting SSc-RP pain and the development of behavioral interventions enhancing coping strategies may reduce the burden of SSc-RP.
Core Outcome Sets Specifically for Longterm Observational Studies: OMERACT Special Interest Group Update in Rheumatoid Arthritis
Authors: Lopez-Olivo Maria A. , Negrón José B. , Zogala Richard J. , Carmona Loreto , Criner Karla , Goel Niti , Gonzalez-Lopez Laura , Ingegnoli Francesca , Leong Amye , March Lyn , Shea Beverly , Strand Vibeke , Tugwell Peter , Westrich-Robertson Tiffany , Zamora Natalia V. , Christensen Robin , Suarez-Almazor Maria E.
Published: March 2019

Objective.

This is an update from the Outcome Measures in Rheumatology (OMERACT) Core Outcomes in Longterm Observational Studies Special Interest Group with a focus on rheumatoid arthritis.

Methods.

Preliminary data and proposed next steps were outlined and discussed by participants.

Results.

Domains identified after initial steps (systematic review and qualitative research) were pain, physical functioning, participation (i.e., work, social), longterm symptoms, fertility/family planning, emotional well-being, coping, financial status, and adverse events including death.

Conclusion.

The group agreed conceptually that short-term core outcomes could be different from longer term ones. Participants emphasized the importance of analyzing the need for core domains specifically for longterm longitudinal observational studies.
A Prospective, Randomized, Double-Blinded Trial Comparing Acetaminophen, Ibuprofen, and Oxycodone for Pain Management After Hand Surgery
Authors: Ilyas Asif M. , Miller Andrew J. , Graham Jack G. , Matzon Jonas L.
Published: February 2019

The goal of this study was to evaluate 3 common oral analgesics—oxycodone (OXY), ibuprofen (IBU), and acetaminophen (ACE)—for pain management following carpal tunnel release (CTR) and trigger finger release (TFR) surgery. Outcome measures were pain scores, capsule consumption patterns, and satisfaction. Carpal tunnel or trigger finger patients indicated to undergo primary, unilateral release received 10 capsules of either OXY (5 mg), IBU (600 mg), or ACE (500 mg) postoperatively. Medications were distributed in a randomized fashion, with both surgeons and patients blinded to the selected analgesic. Postoperatively, patients recorded pain level each day using a 0 to 10 visual analog scale, the number of capsules taken each day, and any adverse effects experienced. Medication distribution among the 188 patients completing the study was 62 OXY, 64 IBU, and 62 ACE. Surgical distribution was 76 TFR, 61 endoscopic CTR, and 51 open CTR. Overall, the mean total number of capsules consumed from postoperative days 0 through 5 for OXY, IBU, and ACE was 3.2, 4.0, and 3.1, respectively (
P
>.05). Mean worst daily pain score for the OXY, IBU, and ACE groups was 2.9, 2.5, and 2.5, respectively (
P
<.05). On subgroup analyses by procedure type, the only difference was found in the open CTR group, with the highest daily pain scores noted in the OXY group (
P
<.05). Nine of the 11 patients experiencing an adverse reaction also came from the OXY group. There were no reoperations or allergic reactions in any group. In this study, no clinically significant difference in pain experience or capsule consumption based on postoperative opioid vs nonopioid medication was identified. Adverse events were highest in the OXY group. In lieu of opioids, the authors suggest prescribing nonopioids first following TFR and CTR surgery. In addition, they advise prescribing 5 to 10 or fewer pills postoperatively regardless of the analgesic selected. [
Orthopedics
. 2019; 42(2):110–115.]
Transformation of Ischial Osteoblastoma Into High-Grade Osteoblastoma-Like Osteosarcoma
Authors: Padubidri Anokha A. , Bertrand Todd E.
Published: February 2019

The authors report an osteoblastoma-like variant of osteosarcoma of the right ischial tuberosity in a 14-year-old boy. Radiographs initially showed a bone-forming lesion of the right ischial tuberosity. The patient underwent biopsy with curettage and bone grafting, with final pathology revealing osteoblastoma. Two years after the initial procedure, he presented with exuberant bone formation about the operative site concerning for recurrence. He underwent a second biopsy that showed transformation into a high-grade osteoblastoma-like osteosarcoma. Results from staging studies were negative for distant metastatic disease. The patient was treated with standard 3-drug chemotherapy along with wide resection of the right ischium with periacetabular reconstruction and total hip arthroplasty. [
Orthopedics.
2019; 42(3):e343–e345.]
Structured Decision-Making Incorporates Stakeholder Values into Management Decisions Thereby Fulfilling Moral and Legal Obligations to Conserve Species
Authors: Brignon William R. , Schreck Carl B. , Schaller Howard A.
Published: March 2019

More than 1,500 species of plants and animals in the United States are listed as threatened or endangered under the Endangered Species Act and habitat destruction is the leading cause of population decline. However, developing conservation plans that are consistent with a diversity of stakeholder (e.g., states, tribes, private landowners) values is difficult. Adaptive management and structured decision-making are frameworks that resource managers can use to integrate diverse and conflicting stakeholder value systems into species recovery planning. Within this framework difficult decisions are deconstructed into the three basic components: explicit, quantifiable objectives that represent stakeholder values; mathematical models used to predict the effect of management decisions on the outcome of objectives; and management alternatives or actions. We use Bull Trout Salvelinus confluentus, a species listed in 1999 as threatened pursuant to the Endangered Species Act, as an example of how structured decision-making transparently incorporates stakeholder values and biological information into conservation planning and the decision process. Three moral philosophies—consequentialism, deontology, and virtue theory—suggest that structured decision-making is a justified method that can guide natural resource decisions in the future, consistent with United States Congress' mandate, and will honor society's obligation to recover Endangered Species Act listed species and their habitats. Natural sciences offer a biological basis for predicting the outcomes of decisions. Additionally, an understanding of how to integrate humanities into scientifically defensible conservation planning is helpful in providing the foundation for lasting and effective species conservation.
Big Data and IoT Opportunities for Small and Medium-Sized Enterprises (SMEs)
Authors: Selamat Siti Aishah Mohd , Prakoonwit Simant , Sahandi Reza , Khan Wajid
Published: February 2019

The advancement of technology and emergence of internet of things (IoT) has exponentially caused a data explosion in the 21st century era. As such, the arrival of IoT is set to revolutionize the development of the small and medium-sized enterprise (SME) organizations by shaping it into a more universal and integrated ecosystem. Despite evidential studies of the potential of advanced technologies for businesses, the SMEs are apprehensive towards new technologies adoption such as big data analytics and IoT. Therefore, the aim of this chapter is to provide a holistic study of big data and IoT opportunities, challenges, and applications within the SMEs context. The authors hope that the outcome of this study would provide foundational information on how the SMEs can partake with the new wave technological advancement and in turn, spurring more SMEs for adoption.
In Search of Footprints of Technology Leadership for Innovation in Strategic Planning
Authors: Ergun Hande Sinem , Gürbüz Fatma Gülruh , Dülger Meral , Samur-Teraman Seray Begüm
Published: February 2019

This chapter explores how technology leadership fosters an innovative technology mindset as manifested in Turkish universities' strategic plans which all show a general focus on technology. Using MAXQDA18 for conducting content analysis of these institutions' strategic plans, the study finds significant differences between successful and unsuccessful universities in terms of technology leadership for innovation. It also demonstrates the universities' outcomes as a result of their efforts in technology leadership and innovative mindset with specific regard to the context of emerging markets. Moreover, given that universities play a significant role in economic and societal development, this study offers valuable findings for policymakers, practitioners, and researchers.
Applications of Image Compression on Agricultural Image Data Analysis
Authors: Seetharaman K.
Published: February 2019

With the advent of the cutting-edge technologies in information repository and communication, data storage is rapidly increased, and it is required to reduce the size of the data. Especially in the case of agricultural image data like types of plants, crops, seeds; kinds of diseases and their remedial pesticides; and the agricultural satellite; images require a huge volume of memory space to store. To avoid this problem, it is required to reduce the size of the data and redundancy of the data. To overcome this problem, this chapter proposes a compression method, based on an adaptive Gaussian Markov random field model for agricultural image data compression, where the images are assumed to be a Gaussian Markov random field. The parameters of the model are estimated, based on the Bayesian approach. The authors use arithmetic coding to store seed values and parameters of the model as it augments the compression ratio. They also have studied the use of the M-H algorithm, which updates the parameters and through which the image contents such as untexturedness are captured.
A Specific NH3 Gas Sensor of a Thick MWCNTs-OH Network for Detection at Room Temperature
Authors: Al-Husseini Afnan H. , Saleh Wasan R. , Al-Sammarraie Abdulkareem M.A.
Published: February 2019

NH3 gas sensor was fabricated based on deposited of Functionalized Multi-Walled Carbon Nanotubes (MWCNTs-OH) suspension on filter paper substrates using suspension filtration method. The structural, morphological and optical properties of the MWCNTs film were characterized by XRD, AFM and FTIR techniques. XRD measurement confirmed that the structure of MWCNTs is not affected by the preparation method. The AFM images reflected highly ordered network in the form of a mat. The functional groups and types of bonding have appeared in the FTIR spectra. The fingerprint (C-C stretch) of MWCNTs appears in 1365 cm-1, and the backbone of CNTs observed at 1645 cm-1. A homemade sensing device was used to evaluate the fabrication network toward NH3 gas at ppm levels as well as the response to sensitivity by changing the concentration. MWCNTs-OH network of 8mm thickness showed an increase in resistance upon exposure to the NH3 gas. The sensor exhibits a good sensitivity for low concentration of NH3 gas at room temperature. The sensitivities of the network were 2.5% at 14ppm, 5.3% at 27ppm and 17.6% at 68ppm. Further investigations showed that the network was specific sensitive to NH3 gas in the environment and not affected by the amount of ambient air.
Autoantibodies against Neurologic Antigens in Nonneurologic Autoimmunity
Authors: Stathopoulos Panos , Chastre Anne , Waters Patrick , Irani Sarosh , Fichtner Miriam L. , Benotti Erik S. , Guthridge Joel M. , Seifert Jennifer , Nowak Richard J. , Buckner Jane H. , Holers V. Michael , James Judith A. , Hafler David A. , O’Connor Kevin C.
Published: March 2019

The aim of this study was to test whether autoantibodies against neurologic surface Ags are found in nonneurologic autoimmune diseases, indicating a broader loss of tolerance. Patient and matched healthy donor (HD) sera were derived from four large cohorts: 1) rheumatoid arthritis (RA) (n = 194, HD n = 64), 2) type 1 diabetes (T1D) (n = 200, HD n = 200), 3) systemic lupus erythematosus (SLE) (n = 200, HD n = 67; neuro-SLE n = 49, HD n = 33), and 4) a control cohort of neurologic autoimmunity (relapsing-remitting multiple sclerosis [MS] n = 110, HD n = 110; primary progressive MS n = 9; secondary progressive MS n = 10; neuromyelitis optica spectrum disorders n = 15; and other neurologic disorders n = 26). Screening of 1287 unique serum samples against four neurologic surface Ags (myelin oligodendrocyte glycoprotein, aquaporin 4, acetylcholine receptor, and muscle-specific kinase) was performed with live cell–based immunofluorescence assays using flow cytometry. Positive samples identified in the screening were further validated using autoantibody titer quantification by serial dilutions or radioimmunoassay. Autoantibodies against neurologic surface Ags were not observed in RA and T1D patients, whereas SLE patients harbored such autoantibodies in rare cases (2/200, 1%). Within the CNS autoimmunity control cohort, autoantibodies against aquaporin 4 and high-titer Abs against myelin oligodendrocyte glycoprotein were, as expected, specific for neuromyelitis optica spectrum disorders. We conclude that neurologic autoantibodies do not cross disease barriers in RA and T1D. The finding of mildly increased neurologic autoantibodies in SLE may be consistent with a broader loss of B cell tolerance in this form of systemic autoimmunity.
Fluid inclusion LA-ICP-MS and whole rock geochemical investigation of possible magmatic contributions to the giant Windy Craggy Besshi-type VMS deposit
Authors: Schmidt M A , Leybourne M I , Peter J M , Petts D , Layton-Matthews D
Published: March 2019

The world-class Windy Craggy Cu-Co-Au deposit, northwestern British Columbia, is investigated to assess potential magmatic contributions to mineralizing fluids in volcanogenic massive sulphide (VMS) deposits. Windy Craggy is of particular interest for two
reasons: 1) its atypically large size and high-grade; and 2) the observation of fluid inclusions with anomalously high salinities. The deposit has recorded fluids with salinities up to 17 weight % equivalent NaCl (most 6-16 weight % equivalent). The Ca/Na values in fluid inclusions
determined by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) are greater than seawater and similar to values from other mafic-dominated VMS systems. The fluid inclusions have variable metal and metalloid concentrations, with positive correlations between Cu, Mn, Zn, Sb, Sn
and Bi. Also analyzed are Windy Craggy host lithologies, including footwall argillites, relatively fresh to highly altered footwall mafic volcanic rocks and stringer and massive sulphides. These inclusions show similar trends and overlap the host rocks in Fe versus Mn and Cu versus Zn, but show
clear excesses over host rocks in antimony, tin, bismuth and similar elements that are commonly ascribed as indicative of magmatic input. We suggest that these excess values strongly point to direct magmatic contributions to the Windy Craggy ore-forming fluids, as opposed to simply reflecting
leaching of metals from the footwall sedimentary and igneous rocks.
Preliminary carbon and oxygen isotope analyses of hydrothermal carbonates from Mississippi Valley-type and REE-F-Ba deposits of the southern Canadian Rocky Mountains - a comparison
Authors: Paradis S , Simandl G J
Published: March 2019

Zinc-lead Mississippi Valley-type (MVT), carbonate-hosted REE-F-Ba and magnesite deposits of the southern Canadian Rocky Mountain Foreland Belt occur along the southwestern edge of the Kicking Horse Rim, a paleo-topographic high that coincides with a carbonate
platform-to-basin facies transition along the ancient Paleozoic margin. Mineralization is hosted in dolostone and is typically associated with sparry and saddle dolomite (ferroan dolomite in association with REE-F-Ba). Carbon and oxygen isotopes done on these carbonate phases show differences and
similarities. All sparry, saddle and ferroan dolomite associated with mineralization have similar delta-18OVPDB values that are lower than those of their host dolostone. However, their delta-13CVPDB values are different with lower values for dolomites at the REE-F-Ba Rock Canyon Creek deposit than
those for the MVT deposits. The depletion in 18O suggests that dolomites associated with mineralization precipitated from or interacted with hydrothermal fluids. The delta-18OVPDB and delta-13CVPDB values of dolomite associated with mineralization at Rock Canyon Creek plot outside the field of
primary igneous carbonatites, and lies on the general trend connecting the southeastern British Columbia carbonatite field to the field for unmineralized host carbonates in the same area.
Hospital Pharmacy Practice and the Way Forward for Pharmacy Education in Thailand
Authors: Ploylearmsang Chanuttha , Kanjanasilp Juntip , Kessomboon Nusaraporn , Suttajit Siritree , Suwannaprom Puckwipa , Sripa Saksit , Sittichotiwong Ratchanok , Srimarueang Thitima , Sonsri Siraprapa , Kittiboonyakun Pattarin
Published: February 2019

-
Mon dernier coup de pinceau
Authors: Roy Myrella
Published: February 2019

-
Sistema OFDM com estimadores de frequência e de fase para sincronização de portadora
Authors: Pacelli Rubem Vasconcelos , Lucena Antônio Macilio Pereira de
Published: March 2019

Orthogonal frequency-division multiplexing, ou OFDM, é uma técnica de modulação utilizada em comunicações sem fio em que se utilizam múltiplas portadoras ortogonais com alguma superposição espectral. Apesar de sua grande robustez contra multipercuso em canais móveis, o sistema OFDM apresenta alta susceptibilidade a erros de sincronismos de frequência e de fase. O presente artigo apresenta uma arquitetura de comunicação em que o receptor é dotado de estimadores de fase e frequência que, em conjunto, mitigam os efeitos dos erros de frequência e de fase. O desempenho do sistema é analisado em termos da taxa de erro de bits. Adicionalmente, é investigado a performance do sistema quando cada um dos estimadores opera isoladamente. Também é avaliado o desempenho dos estimadores em termos da variância do erro dos parâmetros estimados e comparado com o limite de Cramer-Rao. Como principal resultado, verificou-se que o sistema, quando funcionando com os dois estimadores simultaneamente, cancela os erros de sincronismo de frequência e de fase e atinge uma taxa de erro de bits próximo do limite teórico.
Verificação do parâmetro de macrotextura de pavimentos em serviço por meio da análise digital de imagens
Authors: Sousa Elisa Da Silva , Oliveira Francisco Heber Lacerda de
Published: March 2019

A macrotextura é um parâmetro da aderência pneu-pavimento, que, apesar de ser uma das características mais importantes na segurança viária, sua avaliação não é comumente realizada no Brasil. Além disso, os procedimentos recomendados de mensuração da macrotextura ainda são constituídos por ensaios tradicionais que envolvem a interrupção de tráfego por longos períodos. Por outro lado, o desenvolvimento de tecnologias, associadas aos avanços da computação, geraram técnicas como o Processamento Digital de Imagens (PDI), que tem mostrado resultados satisfatórios na avaliação da textura de pavimentos. O presente trabalho busca realizar uma análise comparativa entre valores de profundidade média de macrotextura e os resultados obtidos com a aplicação do PDI em imagens de pavimentos. Para tanto, foram escolhidos pontos em pavimentos asfálticos em serviço localizados no Campus do Pici da Universidade Federal do Ceará (UFC), onde foram coletadas imagens com uma câmera de digital e processadas com a utilização do software Matlab. Posteriormente foi realizado o ensaio da Mancha de Areia. Com os resultados do PDI e do ensaio foi verificada a existência de correlação entre os dados, tendo como base os valores do coeficiente de determinação (R²). Com o desenvolvimento deste trabalho, percebeu-se que o PDI consegue obter resultados satisfatórios na verificação da macrotextura. Porém, a análise das imagens para um único limiar não apresentou correlação adequada, devido às particularidades de cada imagem, como cor e brilho. De forma geral, verificou-se que é possível desenvolver métodos mais eficientes de avaliação de macrotextura, a partir da análise digital de imagens.
Superior ophthalmic vein and ophthalmic artery in immediate evaluation after endovascular treatment of carotid-cavernous fistulas
Authors: Brzozowski Krzysztof , Narloch Jerzy , Zięcina Piotr , Podgórski Andrzej , Piasecki Piotr
Published: February 2019

Purpose

To validate superior ophthalmic vein (SOV) and ophthalmic artery (OA) usefulness in immediate evaluation of new endovascular approaches to treat carotid-cavernous fistulas (CCFs).

Material and methods

A retrospective review of 597 intracerebral malformation embolisations yielded 40 embolisations of CCF in the treatment of 18 patients. Two interventional radiologists performed detailed radiological angiographic assessments.

Results

Mean age at initial admission was 58.9 years (SD 18.5 years, range 24-85 years). Patients presented with: chemosis (50%), ocular bruit (50%), exophthalmos (61%), diminished visual acuity (77.8%), headache (16.7%), and intracerebral haemorrhage (5.55%), and 5.55% were asymptomatic. Unilateral fistulas (10-55.5%) showed more diversified venous drainage pattern than bilateral ones (8-44.4%). There were statistically significant differences in post-traumatic and spontaneous CCF regarding age (p = 0.036), type of fistula (p = 0.0008), and presence of pseudoaneurysm (p = 0.036). 77.8% of patients had increased ipsilateral SOV diameter. SOV enlargement was not associated with type of fistula, history of trauma, or degree of exophthalmos. Ipsilateral ophthalmic artery was visible in all patients on both pre- and postprocedural angiography on lateral projection. Pre- and post-procedural SOV diameter was significantly different. Internal carotid artery patency was 100%, while the overall final angiographic or clinical success was 85.7%. We had three cases of peri-procedural complications.

Conclusions

We reported changeable dynamics of SOV and OA after endovascular treatment of CCFs and proved the feasibility of coils and Onyx-18 in the treatment thereof.
Career Development Influences of Employees Working in Haiti’s Agricultural Extension and Advisory Services
Authors: Albert Bertrhude , Roberts T. Grady , Harder Amy
Published: March 2019

Agricultural Extension and Advisory Services (EAS) provide vital services to individuals within the developing world. Extension personnel are at the heart of extension services because they are the ones who provide essential support, training, and skills to farmers in rural areas. The capacity of extension personnel, therefore, is an essential component of having a robust AET system. The purpose of this research was to explore and describe influences on career development among extension personnel in Haiti. To achieve this purpose, the set objectives of the research were: (a) describe career development influences in a government run extension agency in Haiti; (b) describe career development influences in a private run extension agency in
Haiti; (c) describe career development influences in a grassroots extension agency in Haiti; and (d) compare and contrast career development influences in these agencies. Qualitative data from across the agencies showed common positive influences of: (a) educational background, (b) inservice training, (c) intrinsic motivation, and (d) extrinsic motivation. The common negative influences included: (a) lack of resources and (b) environmental hindrances.
The Impact of Farm Visits on Farmers’ Satisfaction with Extension: Examining the Dependence on Individual Methods in the Caribbean
Authors: Ganpat Wayne G. , Narine Lendel K. , Harder Amy
Published: March 2019

This research sought to investigate the dependence on farm visits in selected Caribbean islands, and estimate the impact of such visits on farmers’ satisfaction with extension. The study utilized a causal-comparative design using a convenience sample from six major farming countries in the Eastern Caribbean. Descriptive frequencies, ANOVA, principal factor analysis, and hierarchical OLS regression models were presented. It appears the low use of alternate approaches to disseminate information to eastern Caribbean farmers has led to a dependency on farm visits. This is unsustainable primarily because of its high cost, given the financial constraints of countries. Results indicated that while farmers were fairly satisfied with extension,
there was a significant difference in satisfaction based on country of residence, and frequency of farm visits was a significant moderator of satisfaction. Countries’ GDP per capita were consistent with satisfaction levels. Proactive initiatives by extension that focus on alternative education approaches are needed; farmers can be clustered into commodity groups and extension can also make use of the good ICT infrastructure in these countries. Extension can influence farmers’ expectations if it capitalizes on other approaches such as ICTs and group visits. Effective use of alternative lower-cost approaches can result in greater ability to deliver
each dimension of quality and match farmers’ expectations. Farm visits have become entrenched as the preferred extension method in the Caribbean. This first-time study, which looks at the issue from an extension and economic perspective, shows the urgent need to revisit the farm visit approach to extension.
A Narrative Review of the Assessment of Extension and Advisory Services on an Agricultural Development Project in North-West Province, South Africa
Authors: Jonathan Ijatuyi Enioluwa , Bontle Mokone
Published: March 2019

The effectiveness of agricultural extension work relies upon the accessibility of staffs that are qualified, roused, conferred and receptive to the consistently evolving social, financial and political condition. This narrative seeks to highlight the role that extension and advisory services play on a specific Agricultural Development Programme Project in North-West Province of South Africa. It also explores how best the provincial government can ensure that policies are developed and timely interventions are delivered with the needs of the farmers being considered first. Recommendations for rapid growth in the cattle and livestock industry in the province were also suggested.
Explaining Agriculture Faculty Members’ Involvement in Study Abroad: Structural Relationships Among Personal-Dimension Variables
Authors: Rampold Shelli D. , Cater Melissa , Bunch J.C. , Blackburn J. Joey , Burnett Michael
Published: March 2019

Agriculture faculty members’ involvement in study abroad programs can influence students’ participation in such. However, faculty members’ involvement may be limited by institutional, professional, and personal factors. This study was conducted to explain agriculture teaching faculty members’ involvement in study abroad programs by examining the structural relationships between their study abroad involvement and personal dimension variables. Results indicated the personal factors influencing faculty members’ involvement in study abroad include their perceptions of the knowledge, skill, and ability (KSA) outcomes of study abroad, awareness of study abroad programs and procedures, and prior international experience (PIE). The effect of faculty members’ perceptions of the KSA outcomes of study abroad programs on their involvement was mediated by their perceptions of the importance of those KSA outcomes for professionals in their field. Further, faculty members’ perceived importance of KSA outcomes was moderated by PIE. Recommendations for future practice include providing professional development and training to increase faculty members’ awareness of study abroad and increase opportunities for faculty members to gain international experiences. Future research should include replication of this study with agriculture faculty members at other institutions and the examination of relationships among professional and institutional dimension factors.
An Analysis of Evaluation Methods Implemented in Studies Published in the Journal of International Agricultural and Extension Education from 1994 to 2018: A 25 Year Review
Authors: Murphrey Theresa Pesl , Koswatta Taniya J. , Dooley Kim E. , Edgar Leslie D.
Published: March 2019

Evaluation has been identified as a critical pathway to meet the grand challenges facing agriculture to feed the world. Understanding evaluation models and practices used in articles published in the Journal of International Agricultural and Extension Education (JIAEE) allowed us to identify areas of focus, need, and improvement. This content analysis assessed JIAEE articles published from 1994 to 2018 for evaluation methods implemented according to characteristics outlined by Stufflebeam and Coryn (2014). This study initially identified 384 possible articles for consideration. Upon further assessment, 81 articles were identified as maintaining characteristics appropriate for review. Of these articles, the majority (70%) did not specifically identify an evaluation approach, even though 21% of all feature articles published over the past 25 years can be considered an evaluation. Few published evaluation articles specifically identified an evaluation approach; rather, the majority merely described the methods without using evaluation terminology, and the majority of the examined articles did not substantially cite evaluation literature (53%). Additionally, the majority of published evaluation articles were quantitative (56%). Researchers publishing in JIAEE should be assured that
qualitative and mixed method evaluation studies are also acceptable. Evaluation studies focused on Stufflebeam and Coryn’s evaluation criteria of feasibility, safety, equity, and probity should be encouraged. Additionally, workshops or training opportunities to advance understanding in evaluation processes and procedures may be valuable.
The Future of Extension: A Network Emergence Perspective from the Case of the Global Forum for Rural Advisory Services
Authors: Davis Kristin , Dolly David , Lamm Alexa J. , Lamm Kevan W.
Published: March 2019

Extension, as a socially-based institution, must constantly evolve with society. This case study on the Global Forum for Rural Advisory Services uses social network theory to add to the literature on network emergence in the context of extension. The researchers explored how an extension network evolved in response to global agricultural issues. The use of a qualitative content analysis of the eight themes of the annual meeting of the network showed how the Forum changed in response to current events and regional needs. The Forum first built and consolidated a network of global extension members and then moved to an outward focus in terms of relations within and outside of extension. Analysis revealed the network first focused on simple, basic
themes of interest to the knowledge network, and slowly expanded to wider and more complex topics that involved a richer network of actors. This case implies that extension institutions, which are on the front line of trends stemming from societal shifts, are thus positioned to play a crucial role in technology transfer and sensitization of global agricultural issues.
Tornado-scale vortices in the tropical cyclone boundary layer: numerical simulation with the WRF–LES framework
Authors: Wu Liguang , Liu Qingyuan , Li Yubin
Published: February 2019

Abstract. A tornado-scale vortex in the tropical cyclone (TC) boundary layer (TCBL)
has been observed in intense hurricanes and the associated intense turbulence
poses a severe threat to the manned research aircraft when it penetrates
hurricane eyewalls at a lower altitude. In this study, a numerical experiment
in which a TC evolves in a large-scale background over the western North
Pacific is conducted using the Advanced Weather Research and Forecast (WRF)
model by incorporating the large-eddy simulation (LES) technique. The
simulated tornado-scale vortex shows features similar to those revealed with
limited observational data, including the updraft–downdraft couplet, the
sudden jump of wind speeds, the location along the inner edge of the eyewall,
and the small horizontal scale. It is suggested that the WRF–LES framework
can successfully simulate the tornado-scale vortex with grids at a
resolution of 37 m that cover the TC eye and eyewall. The simulated tornado-scale vortex is a cyclonic circulation with a small
horizontal scale of ∼1 km in the TCBL. It is accompanied by strong
updrafts (more than 15 m s−1) and large vertical components of
relative vorticity (larger than 0.2 s−1). The tornado-scale vortex
favorably occurs at the inner edge of the enhanced eyewall convection or
rainband within the saturated, high-θe layer, mostly below
an altitude of 2 km. In nearly all the simulated tornado-scale vortices,
the narrow intense updraft is coupled with the relatively broad downdraft,
constituting one or two updraft–downdraft couplets, as observed by the
research aircraft. The presence of the tornado-scale vortex also leads to
significant gradients in the near-surface wind speed and wind gusts.
Nocturnal boundary layer turbulence regimes analysis during the BLLAST campaign
Authors: Yus-Díez Jesús , Udina Mireia , Soler Maria Rosa , Lothon Marie , Nilsson Erik , Bech Joan , Sun Jielun
Published: March 2019

Abstract. A night-time turbulence regime classification, the so-called HOckey-Stick Transition (HOST) theory, proposed by Sun et al. (2012) from the Cooperative Atmosphere-Surface Exchange Study 1999 (CASES-99) is explored using data from the Boundary-Layer Late Afternoon and Sunset Turbulence (BLLAST) field campaign which took place during the summer 2011 in the north of the central French Pyrenean foothills. Results show that the HOST turbulence relationships for the BLLAST field campaign data is strongly dependent on both the meteorological and orographic features. The HOST pattern only appears for nights when a stably stratified boundary layer can be developed, corresponding to fair weather and clear sky nights, when the flow is generated by the nearby orography, from the south and southeast directions. Those flows strongly influenced by the orography may generate intermittent or enhanced turbulence. When considering the whole dataset for these flow directions, several enhanced turbulence points are found to be associated with sudden wind speed and directional shear transitions. In contrast, flows from other directions do not reproduce the HOST relationship and the turbulence relationship is almost linear, independent of the vertical temperature gradients, corresponding to flows driven by mesoscale or synoptic scales. In addition we identify examples of gravity waves and top-down turbulent events that lead to transitions between the turbulence regimes.
The impact of increases in South Asian anthropogenic emissions of SO2 on sulfate loading in the upper troposphere and lower stratosphere during the monsoon season and the associated radiative impact
Authors: Fadnavis Suvarna , Kalita Gayatry , Rowlinson Matthew , Rap Alexandru , Li Jui-Lin Frank , Gasparini Blaž , Laakso Anton , Müller Rolf
Published: March 2019

Abstract. The Asian summer monsoon plays a key role in changing aerosol amounts in the upper troposphere and lower stratosphere (UTLS) via convective transport. Here, we use the ECHAM6-HAMMOZ global chemistry–climate model to investigate the transport of anthropogenic South Asian sulfate aerosols and their impact on the UTLS. Our experiments (ten-member ensemble) with SO2 emissions enhanced by 48 % over South Asia, based on an Ozone Monitoring Instrument (OMI) satellite observed rising trend of ~ 4.8 % per year during 2006–2017, simulate how the Asian sulfate aerosols are convectively transported to the UTLS. The tropospheric increase in SO2 leads to an increase in UTLS sulfate aerosol loading of 10–33 % over South Asia and 5–10 % over the high latitudes in the northern hemisphere. The enhanced sulfate aerosols lead to warming (0.1 ± 0.06 to 0.6 ± 0.25 K) in the lowermost stratosphere and cooling (−0.1 ± 0.06 to −0.8 ± 0.41 K) in the troposphere in the Northern Hemisphere. The estimated mean direct radiative forcing at the top of the atmosphere (TOA) induced by the increase in South Asian aerosol emissions is −0.2 to −1.5 W m−2 over north India during the monsoon season. The decrease in vertical velocity and the associated enhanced stability of the upper troposphere in response to increased SO2 emissions will likely have a weakening effect on the South Asian monsoon.