bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study on the Compressive Strength Properties and Quality Control of Lightweight Foamed Magnesia Composite Using Super Absorbent Polymers as Base Material for Biological Panels
Authors: Oh Sung Rok , Kim Ki Hyung , Choi Yung Wang
Published: November 2018

In this paper, the compressive strength quality characteristics of lightweight formedmagnesia composite using super absorbent polymer as basic material for biological panels wereevaluated. The experimental parameters were evaluated with respect to the compressive strength ofthe mortar according to the water binder ratio (W/B), the volume ratio of fine aggregate (Vs/Vm), theamount of foaming agent (FA) and the amount of super absorbent polymer (SAP). Statistical analysiswas performed on the compressive strength obtained through the experiment and the influencecoefficient on the compressive strength quality was obtained. The compressive strength qualityprediction model equation of the magnesia composite is proposed through the obtained influencecoefficient. The proposed model equation shows that the experimental and predicted values are over80%.
A Study on the Flow Characteristics and Quality Control of Lightweight Foamed Magnesia Composite Using Super Absorbent Polymers as Base Material for Biological Panels
Authors: Oh Sung Rok , Lee Chul Goo , Choi Yung Wang
Published: November 2018

In this paper, the flow characteristics of a lightweight formed magnesia composite usingsuper absorbent polymer as base material for biological panels were evaluated. The experimentalparameters were evaluated with respect to the flow of the mortar according to the water binder ratio(W/B), the volume ratio of fine aggregate (Vs/Vm), the amount of foaming agent (FM) and theamount of super absorbent polymer (SAP). Statistical analysis was performed on the flow obtainedthrough the experiment and the influence coefficient on the flow quality was obtained. The flowquality prediction model equation of the magnesia composite is proposed through the obtainedinfluence coefficient. The proposed model equation shows that the experimental and predicted valuesare over 90%.
Study on High-Temperature Creep Behavior of T23 and T24 Steels
Authors: Pan Jin Ping , Tu Shu Heng , Chu Ding Jun , Zhu Xin Wei , Hu Bin , Tan Lian Jiang
Published: November 2018

A progressive increase of plant efficiency calls for new requirements of heat-resistantsteels used in the boiler and piping systems. In this paper, high-temperature creep behavior of T23and T24 steels were studied. Creep tests over a long period of time have been conducted for bothsteels at different temperatures. The creep mechanisms of the two steels have been clarified byanalyzing the minimum creep rate versus stress data. Besides, the creep rupture data from the creeptests were in good accordance with theoretical simulation on the basis of the CDM model over a longtime. Creep temperature has great effects on the rupture strength of the two steels. By creep ruptureexperiments and appropriate modelling, the high-temperature creep behavior can be well described.
A Basic Numerical Peening Indentation Model with Geometric Indenter Based on Dynamic Impact Analysis
Authors: Kim Taeh Yung , Lee Nam Ju
Published: November 2018

As shot peening is widely used to improve the crack resistance of various metals, it isimportant to have an accurate method to calculate the compressive residual stress produced by thisprocess. To this end, this paper presents a finite element (FE) model that includes an indenterdesigned from a dent profile. The results of compressive residual stress obtained by using thisindenter model and a normal shot impact model are compared. The indentation FE solution with anunmodified indenter is close to that obtained using the rigid shot (RS) impact model. The solutionfor the indentation FE model with a modified indenter closely matches that for an elasticdeformable shot (EDS) impact model. These results confirm the effectiveness of the indentation FEmodel based on the dent profile. This model can replace the present impact FE models to calculatethe compressive residual stress produced by shot peening.
The Effect of Botanical Pesticide Extract Addition on the Nutrient Release of Fertilizer from Poultry Manure
Authors: Oky Amelia Sandra , Purnomo Chandra Wahyu , Mulyono Panut
Published: November 2018

Slow release fertilizer with pesticide (SRFP) has been formulated to provide nutrientenriched with pesticide using all natural compound. Matrix formulation is used with poultry manure(PM) as the nutrient source as well as the solid matrix for incorporating neem leave (Azadirachtaindica a.juss) and gendarussa leave (Justicia gendarussa burm) extract as the active compounds. Inthis study, the release of nutrient i.e. nitrogen by the addition of the two leave extracts during SRFPpreparation has been investigated using sand bed column leaching test. The leachate solution wasanalysed by Kjedahl method to measure total nitrogen amount released. Different volume of the leaveextract was investigated to study the effect of the extract addition on the release of the nitrogen. It isshown that the higher the volume of the leaves extract added during the granulation process, the fasterthe release of the nutrient.
Modification of Chemical Properties of Shellac with Glycerol and Acrylic Acid
Authors: Marareza Harry , Rochmadi  , Sarto
Published: November 2018

Shellac is a natural product which has been presumed as a fragile polymer due to itschemical properties. The objective of this study was to improve chemical properties of shellac by themodification with different concentration of glycerol and acrylic acid. Shellac was reacted withglycerol at various temperature and amounts of glycerol. The intermediate product was reacted withacrylic acid at different concentration. Acid value, hydroxyl groups, and free glycerol concentrationof modified shellac was determined. The result showed that acid value gradually decrease alongincreasing temperature for each ratio of glycerol and acrylic acid to shellac. The concentration ofhydroxyl groups rise as temperature and ratio increases. Furthermore, free glycerol concentration felldown along with the rise temperature. Modification chemical properties of shellac with glycerol andacrylic acid can be applied for the further study to enhance shellac properties.
Natural Zeolite Effect on Liquid Product Characteristics of Hydrothermal Treatment
Authors: Purnomo Chandra Wahyu , Lalak Tarbiyatun Nasyin Maleiva , Sarto
Published: November 2018

Indonesia has an abundant resource of natural zeolite due to its geological location involcano pathway. This material has been widely employed in various processing technologies. Inspite of the diverse applications, the usage of zeolite in the hydrothermal treatment (HT) of waste israrely found. Recently, HT shows a promising technology for municipal solid waste (MSW)treatment. The main objective in this research is to study the influence of zeolite addition in HT ofMSW in terms of liquid product properties. In this research, equal weight of sawdust and crushedplastic bottle waste (PET) were used to represent MSW. The waste mixture was loaded into a 2Lbatch reactor with zeolite addition from Min (0%) to 20%wt. using 220oC temperature treatment.The liquid side product was then investigated in terms of organic compounds, functional groups,potassium (K) and phosphate (P) contents. It is assigned that zeolite addition enhancesdecomposition process of the MSW into various organic compounds as well as improving P ad Kconcentration in liquid product that can be utilized for fertilizer preparation.
Study of Antibacterial Activity of Nanosilver-Polypropylene Composite against Contaminated Bacteria in Molasses
Authors: Pongsapasiritat Kittiya , Jumnienkul Nongnapat , Dangtungee Rapeepun , Sriariyanun Malinee
Published: November 2018

The nanosilver particles are attractive in the research field of nanotechnology due to one of their applications as an effective antibacterial agent. The main objective of the current research is to inhibit the bacterial growth in the molasses to decrease the rate of total sugar degradation caused by contaminated bacteria. The polypropylene masterbatch containing with AgNPs (PP/AgNPs) was prepared and tested against contaminated bacterial species identified in molasse. The percentage of bacterial inhibition was calculated by observing the viability of bacteria cultures by using spread plate technique after treated with PP/AgNPs masterbatch in batch experiment. The concentrations of nanoparticles in masterbatch were varied to be 200, 500, 1000, 1200 and 1500 ppm. At 1500 ppm, the compromised antibacterial activities were observed in all tested bacterial species with 2-h-long exposure time. The results in this study could be further applied to fit in operation of molasse use in industrial scale in various application, including bioethanol production.
Effect of Solution Treatment Temperature on Microstructure and Mechanical Properties of Al-5.1Zn-2Mg-0.1Ti (wt. %) Produced by Squeeze Casting
Authors: Wijanarko Risly , Angela Irene , Sofyan Bondan Tiara
Published: November 2018

Al 7xxx alloy is a heat treatable Al alloy with superior strength. Solution treatment in precipitation hardening sequence of the alloy has an important role to dissolve second phases and bring vacancies out to form precipitates in the ageing process. Another strengthening can be done by Ti addition as grain refiner. As cast alloy by squeeze casting was homogenized at 400 °C for 4 h. Solution treatment was conducted at 220, 420, and 490 °C, followed by rapid quenching. Subsequent ageing was conducted at 130 °C for 48 h. Characterization was performed by optical microscope, SEM-EDS (Scanning Electron Microscopy – Energy Dispersive Spectroscopy), Rockwell hardness testing, XRD (X-Ray Diffraction), and STA (Simultaneous Thermal Analysis). Ti added alloy showed rounder grains, lower hardness, and more reduction in second phase volume fraction along with increasing solution treatment temperature than those in alloys without Ti addition. Otherwise, the alloy final hardness was increasing and higher after the ageing process due to higher second phase dissolution which leads to more precipitates formed.
Various types of dialogues and features of a corrective dialogue in the Qur’an
Authors: Maaref Majid
Published: November 2018

The Qur’an is the book of Allah’s dialogue with humans. At the same time, this book itself contains a diverse number of dialogues including the prophets’ dialogues with people, the wise peoples’ dialogues, the divine selected figures’ dialogue with people, the angels’ dialogue with humans, various classes of humans’ dialogue with each other, human’s dialogue with his or her own organs and such likes. The dialogues in the Qur’an have various types of attitudes ranging from criticism, alteration, trials and reforms whose latter samples are manifested in the prophets’ dialogue with their people. To be in agreement with the truth, to be authentic and to be proportional with the society, customs, profitability, clearness, purity, acceptability and bearing, beauty and goodness are all the features of ideal dialogues and speeches in the Qur’an. Features such as rationalism, religious tolerance, endurance and self-constraint, humbleness in words, sympathy with the opponents with an emphasis on commonalities and avoiding any kind of polemic debates and violence in the process of dialogue, and observing politeness and dignity of the addresses are among the most important features of corrective dialogue in the Qur’an.
Electronic health record system in the public health care sector of South Africa: A systematic literature review
Authors: Katurura Munyaradzi C. , Cilliers Liezel
Published: November 2018

Background: South Africa is planning to implement the National Health Insurance (NHI) scheme in the near future. The NHI is intended to improve the accessibility of quality health care services for all South African citizens. For the NHI to achieve this objective, an electronic health record (EHR) system to register and track patients who visit different health care providers will have to be developed.Aim: To identify critical success factors for the implementation of EHRs in South Africa’s public health care sector.Setting: This study reviewed studies on EHR implementation in African countries published between 2006 and 2017.Methods: The study made use of a systematic literature review to identify barriers to the implementation of EHRs in the public health care sector.Results: Fifteen articles were included in the study. The study identified technical, social and environmental barriers to the implementation of EHRs. The barriers could further be broken down into lack of supporting infrastructure; user training and commitment; political influence or strategy; legislation and regulations; and the lack of a framework for implementation and management of EHRs. The study suggests six main recommendations for the successful implementation of EHRs in South Africa’s public health care sector.Conclusion: The study recommended investing in alternative infrastructure facilities, incentivising the health informatics field to attract and retain information and communication technology professionals and to encourage the participation of all stakeholders in the development process to develop context-relevant e-health implementation strategies, legislation and frameworks. Government should also allocate separate budgets for e-health projects.
Estimates for solutions of Dirac equations and an application to a geometric elliptic-parabolic problem
Authors: Chen Qun , Jost Jürgen , Sun Linlin , Zhu Miaomiao
Published: November 2018

We develop estimates for the solutions and derive existence and uniqueness results of various local boundary value problems for Dirac equations that improve all relevant results known in the literature. With these estimates at hand, we derive a general existence, uniqueness and regularity theorem for solutions of Dirac equations with such boundary conditions. We also apply these estimates to a new nonlinear elliptic-parabolic problem, the Dirac-harmonic heat flow on Riemannian spin manifolds. This problem is motivated by the supersymmetric nonlinear

\sigma

-model and combines a harmonic heat flow type equation with a Dirac equation that depends nonlinearly on the flow.
On the monotonicity of Hilbert functions
Authors: Puthenpurakal Tony J.
Published: November 2018

In this paper we show that a large class of one-dimensional Cohen–Macaulay local rings

(\mathcal A,\mathfrak m)

has the property that if

M

is a maximal Cohen–Macaulay

A

-module then the Hilbert function of

M

(with respect to

\mathfrak m

) is non-decreasing. Examples include (1) complete intersections

A = Q/(f,g)

where

(Q,\mathfrak n)

is regular local of dimension three and

f \in \mathfrak n^2 \setminus \mathfrak n^3

; (2) one dimensional Cohen–Macaulay quotients of a two dimensional Cohen–Macaulay local ring with pseudo-rational singularity.
On the values of unipotent characters in bad characteristic
Authors: Geck Meinolf
Published: November 2018

Let

G(q)

be a Chevalley group over a finite field

\mathbb F_q

. By Lusztig’s and Shoji’s work, the problem of computing the values of the unipotent characters of

G(q)

is solved, in principle, by the theory of character sheaves; one issue in this solution is the determination of certain scalars relating two types of class functions on

G(q)

. We show that this issue can be reduced to the case where

q

is a prime, which opens the way to use computer algebra methods. Here, and in a sequel to this article, we use this approach to solve a number of cases in groups of exceptional type which seemed hitherto out of reach.
High Prevalence of Extended-Spectrum Beta-Lactamase CTX-M–Producing Escherichia coli in Small-Scale Poultry Farming in Rural Ecuador
Authors: Hedman Hayden D. , Eisenberg Joseph N. S. , Vasco Karla A. , Blair Christopher N. , Trueba Gabriel , Berrocal Veronica J. , Zhang Lixin
Published: November 2018

Small-scale farming may have large impacts on the selection and spread of antimicrobial resistance to humans. We conducted an observational study to evaluate antibiotic-resistant Escherichia coli populations from poultry and humans in rural northwestern Esmeraldas, Ecuador. Our study site is a remote region with historically low resistance levels of third-generation antibiotics such cefotaxime (CTX), a clinically relevant antibiotic, in both poultry and humans. Our study revealed 1) high CTX resistance (66.1%) in farmed broiler chickens, 2) an increase in CTX resistance over time in backyard chicken not fed antibiotics (2.3–17.9%), and 3) identical blaCTX-M sequences from human and chicken bacteria, suggesting a spillover event. These findings provide evidence that small-scale meat production operations have direct impacts on the spread and selection of clinically important antibiotics among underdeveloped settings.
Fatal Snakebite Envenoming and Agricultural Work in Brazil: A Case–Control Study
Authors: Mise Yukari Figueroa , Lira-da-Silva Rejâne Maria , Carvalho Fernando Martins
Published: November 2018

We investigated the association between fatal snakebite envenoming and agricultural work in Brazil, considering the effects of relevant covariables. A nested case–control study was performed using 1,119 fatal cases of snakebite envenoming among persons aged ≥ 10 years, notified to the Brazilian official reporting system, from 2004 to 2015. As controls, 4,476 cases were randomly selected from the 115,723 nonfatal cases of snakebite, without missing data, that occurred in the same time period. The main predictor was occupation in the agriculture sector; the main outcome was death by snakebite envenoming. Logistic regression analysis was used to investigate the main association, controlling for the effects of relevant covariables. Fatal cases had a 20% greater chance (odds ratio [OR] = 1.20; 95% confidence interval [CI]: 1.00–1.39) of being among farmers than the controls. However, late (≥ 6 hours) time to treatment (OR = 2.00; 95% CI: 1.70–2.36); adequate antivenom with an insufficient (OR = 1.25; 95% CI: 1.04–1.50) or excessive (OR = 4.89; 95% CI: 4.10–6.03) number of vials; inadequate antivenom and insufficient or excessive number of vials (OR = 3.87; 95% CI: 2.40–6.24); no use of antivenom (OR = 2.05; 95% CI: 1.60–2.64); and age ≥ 60 years (OR = 1.98; 95% CI: 1.61–2.44) were more strongly associated with lethality. Lethality was 1.0% in the period, being 0.47% among those receiving early and adequate treatment. We concluded that in Brazil, fatal snakebite envenoming was associated with agricultural work, controlling for relevant covariates. However, quality of health care provided and greater age were much more strongly associated with lethality.
Chloroquine–Primaquine Therapeutic Efficacy, Safety, and Plasma Levels in Patients with Uncomplicated Plasmodium vivax Malaria in a Colombian Pacific Region
Authors: Mesa-Echeverry Esteban , Niebles-Bolívar Mayra , Tobón-Castaño Alberto
Published: November 2018

In Colombia, published studies for the treatment of uncomplicated Plasmodium vivax malaria with chloroquine–primaquine (CQ-PQ) are scarce. The aim of the study was to evaluate the therapeutic efficacy and safety profile of this combination. A clinical trial was performed in adults with uncomplicated P. vivax malaria using the 28-day World Health Organization validated protocol. Patients received supervised antimalarial treatment and the primary efficacy end point was the clinical and parasitological response. Safety was assessed through adverse events surveillance, and plasma levels of antimalarial drugs were measured. A total of 77 patients were included. Adequate clinical and parasitological response rate diagnosed by thick blood smear examination was achieved in 72 of 73 patients (98.6%) with a complete 28-day follow-up. There were two parasitological therapeutic failures (TFs) (2.9%) on day 28, established by polymerase chain reaction among 68 patients, one of them with a positive film. No adverse events were detected. After completing the antimalarial treatment, all patients reached adequate plasma concentrations of CQ and desethylchloroquine (DECQ), with medians of 302.9 and 104.0 ng/mL, respectively. Uncomplicated P. vivax malaria treatment with CQ–PQ standard treatment was effective and safe in the study population; TFs were not associated with low plasma levels of CQ and DECQ.
A comparative study of challenger-incumbent strategies in Ghanaian presidential campaign: the case of John Agyekum Kufuor
Authors: Mensah Opoku Eric , Sarfo-Adu Kwasi , Afful Joseph Benjamin Archibald
Published: November 2018

In recent years, growing research interest in challenger-incumbent campaign communication has provided illuminating insights into the kinds of strategies favoured by challengers and incumbents in presidential elections. However, most of these studies tend to focus on two or more presidential candidates. This has resulted in little knowledge about the rhetorical strategies of the same candidate who contested as a challenger in a previous election, became president and won again as an incumbent in the next election. In this paper, we explore and compare challenger-incumbent strategies as they manifest in the presidential campaign of John Agyekum Kufuor’s (JAK) who won the 2000 presidential elections as a fresh candidate and, for a second term, won in 2004, as an incumbent. A qualitative analysis of four of his campaign speeches in both elections revealed that as a challenger, JAK presented  himself as an agent of change and resorted to negative campaigning rooted in bellicose rhetoric. He marketed himself with can-do optimism that portrayed him as the quintessence of the cure-all for Ghana’s socio-economic problems. Conversely, as an incumbent, JAK adopted temperate rhetoric amidst self-promotion on the wings of his accomplishments and personal qualities. He appropriated the ethos of traditional rulers to present a viable image of himself as a performing president. The findings of the study have implications for presidential candidates, particularly, for challengers who are eager to win elections and incumbents keen to maintain power.Keywords: challenger campaign, candidate, incumbent, presidential
Ethical reorientation and the Nigeria moral question
Authors: Eresia-Eke Agha
Published: November 2018

Man is gregarious by nature and thus has come to live in communities of various descriptions. Social life demands orderliness, and to endure its existence, norms and rules become integral parts of any community or society. It is however common knowledge that some members of most human communities and societies exhibit behaviours that strain the tolerance level of other members of the community. Those who exhibit such acts are labelled deviants or preverts and their actions termed criminal when sanctioned by the laws of the state. It is as a consequence of this that Nigeria, like many countries of the world, has witnessed high level of activities and life-styles considered inimical to the good of society. Efforts have therefore been made by different government regimes to stem the trend. The thrust of this paper in this regard becomes an attempt to expose the specificities of these government programmes to know what extent intended goals of checking those social maladies were archieved. However, without prejudice or bias against whatever the achievements of these government policies and programmes of government were, it is the position of this paper that those measures were inadequate. And this accounts for the reason those misbehaviours have escalated rather than abate. To wrest the challenge of the Nigeria moral question which calls for ethical reorientation, the paper calls for the adoption of the ‘Socratic Model’ this lifted the Athenian society of Socrates’ time out from its worst moral decadence.
Subjectivity and ethnocentric leadership approaches in tackling the Nigerian question
Authors: Amugo Frank , Chinda D , Izeoma C
Published: November 2018

Subjectivity has been an all-important concept for academic research, as well as used as a tool for intervening in social and political life of a people, since the 1960s and 1970s. The idea of subjectivity had a catalytic impact in changing the terms of the debate in History and Social Sciences, postcolonial theory, gender studies, cultural and media studies, social theory, and the other disciplines in the humanities. Subjectivity which relates to the quality of possessing perspectives and experiences, feelings, beliefs, desires, and power employed in the attempt at explanation for what influences, and informs people’s judgment about truth or reality. In this paper, we shall attempt to examine the role of leaders of the Nigerian state in tackling the challenges/problems faced by the various sections of the Nigerian polity. These problems include, religious crisis, marginalization, resource equity, among others, and they constitute the National question. The paper concludes that the difficulty in answering the Nigerian question, to a large extent, result from the influence of subjectivity in viewing and tackling these problems by successive leaders emerging mainly from the majority tribes of the country.Keywords: Subjectivity, Leadership, Nigerian Question, Ethnocentrism
Exploring an association between online alcohol advertisements and alcohol drinking among college students in Kenya
Authors: Guyo Abdirizak Garo , Yu Hong , Muthiani Joseph , Kembero Richard Mbaraka
Published: November 2018

Alcohol drinking among young people is a major global public health concern. The situation has been aggravated further by the advent of the internet and subsequent development of social media as a tool for online alcohol marketing. This exploratory study sought to find out the prevalence of alcohol advertisements on social media and its possible influence on alcohol drinking among college students in Kenya. Based on a field survey conducted in Nairobi, (N=70), this study has established that that there was heavy presence of alcohol advertisements on social media scene in Kenya. Although statistically, there was huge gender disparity, the final results showed that there was significant  association between alcohol ads on social media and college student’s possible alcohol drinking habits This study concludes that there is need for the stakeholders in public health promotions to formulate policies aimed at mitigating against the challenges posed by unrestricted access to online alcohol ads by the youth in order to prevent them from being lured into early alcohol drinking by the alcoholic beverage makers.Keywords: alcohol abuse; influence; online ads; youth; Kenya
Analytical Hierarchy Process (AHP) approach for selecting stationery suppliers in selected universities in Benin City
Authors: Omorogbe Dickson E.A. , Iguodala Wilfred A.
Published: November 2018

Supplier Selection is a multi-criteria decision making (MCDM) Problem. It requires the evaluation of both qualitative and quantitative factors. Selecting the best supplier among several alternatives is an enormous task for decision makers (DMs) and procurement managers (PMs). Since no single supplier can excel in all the attributes required by DMs. this paper adopted both the quantitative and qualitative factors in the selection process. Also, this paper applied the AHP approach in the selection of stationery suppliers using real life data from selected universities in Benin City.Keywords: Analytical Hierarchy process, stationary, multi-criteria decision making
Lower tropospheric ozone over the North China Plain: variability and trends revealed by IASI satellite observations for 2008–2016
Authors: Dufour Gaëlle , Eremenko Maxim , Beekmann Matthias , Cuesta Juan , Foret Gilles , Fortems-Cheiney Audrey , Lachâtre Mathieu , Lin Weili , Liu Yi , Xu Xiaobin , Zhang Yuli
Published: November 2018

Abstract. China is a highly polluted region, particularly the North China Plain (NCP).
However, emission reductions have been occurring in China for about the last
10 years; these reduction measures have been in effect since 2006 for SO2 emissions and
since 2010 for NOx emissions. Recent studies have shown a
decrease in the NO2 tropospheric column since 2013 that has been attributed to
the reduction in NOx emissions. Quantifying how these emission
reductions translate regarding ozone concentrations remains unclear due to
apparent inconsistencies between surface and satellite observations. In this
study, we use the lower tropospheric (LT) columns (surface – 6 km a.s.l. – above sea level)
derived from the IASI-A satellite instrument to describe the variability and
trend in LT ozone over the NCP for the 2008–2016 period. First, we investigate the IASI
retrieval stability and robustness based on the influence of atmospheric
conditions (thermal conditions and aerosol loading) and retrieval sensitivity
changes. We compare IASI-A observations with the independent IASI-B
instrument aboard the Metop-B satellite as well as comparing them with surface and ozonesonde
measurements. The conclusion from this evaluation is that the LT ozone columns
retrieved from IASI-A are reliable for deriving a trend representative of the
lower/free troposphere (3–5 km). Deseasonalized monthly time series of LT
ozone show two distinct periods: the first period (2008–2012) with no
significant trend (<−0.1 % yr−1) and a second period (2013–2016) with a
highly significant negative trend of −1.2 % yr−1, which leads to an
overall significant trend of −0.77 % yr−1 for the 2008–2016 period. We
explore the dynamical and chemical factors that could explain these negative
trends using a multivariate linear regression model and chemistry transport
model simulations to evaluate the sensitivity of ozone to the reduction in
NOx emissions. The results show that the negative
trend observed from IASI for the 2013–2016 period is almost equally attributed to
large-scale dynamical processes and emissions reduction, with the large El Niño
event in 2015–2016 and the reduction of NOx emissions being
the main contributors. For the entire 2008–2016 period, large-scale
dynamical processes explain more than half of the observed trend, with a
possible reduction of the stratosphere–troposphere exchanges being the
main contributor. Large-scale transport and advection, evaluated using CO as
a proxy, only contributes to a small part of the trends (∼10 %). However,
a residual significant negative trend remains; this shows the limitation of
linear regression models regarding their ability to account for nonlinear processes such as ozone
chemistry and stresses the need for a detailed evaluation of changes in chemical
regimes with the altitude.
Convective hydration in the tropical tropopause layer during the StratoClim aircraft campaign: Pathway of an observed hydration patch
Authors: Lee Keun-Ok , Dauhut Thibaut , Chaboureau Jean-Pierre , Khaykin Sergey , Krämer Martina , Rolf Christian
Published: November 2018

Abstract. The source and pathway of the hydration patch in the TTL (Tropical Tropopause Layer) that was measured during the StratoClim field campaign during the Asian summer monsoon in 2017, and its connection to convective overshoots are investigated. During flight #7, two remarkable layers are measured in the TTL namely, (1) moist layer (ML) with water vapour content of 4.8–5.7 ppmv in altitudes of 18–19 km altitudes in the lower stratosphere, and (2) ice layer (IL) with ice content up to 1.9 eq. ppmv in altitudes of 17–18 km in the upper troposphere around 06:30 UTC on 8 August to the south of Kathmandu (Nepal). A Meso-NH convection-permitting simulation succeeds in reproducing the characteristics of ML and IL. Through analysis, we show that ML and IL are generated by convective overshoots that occurred over the Sichuan basin about 1.5 day before. Overshooting clouds develop up to 19 km, hydrating the lower stratosphere of up to 20 km with 6401 t of water vapour by a strong-to-moderate mixing of the updraughts with the stratospheric air. A few hours after the initial overshooting phase, a hydration patch is generated, and a large amount of water vapour (above 18 ppmv) still remains at even higher altitudes up to 20.5 km a.s.l. while the anvil cloud top descends to 18.5 km. At the same time, a great part of the hydrometeors falls shortly, and the rest sublimates. Meanwhile ice sediments out, the water vapour concentration in ML and IL decreases due to turbulent diffusion by mixing with the tropospheric air. As the hydration patch continues to travel toward the south of Kathmandu, tropospheric tracer concentration increases up to ~ 30 and 70 % in ML and IL, respectively. The air mass in the layers becomes gradually diffused and it has less and less water vapour and ice content by mixing with the dry tropospheric air.
Cross-validation of GPS tomography models and methodological improvements using CORS network
Authors: Brenot Hugues , Rohm Witold , Kačmařík Michal , Möller Gregor , Sá André , Tondaś Damian , Rapant Lukas , Biondi Riccardo , Manning Toby , Champollion Cédric
Published: November 2018

Abstract. Using data from the Continuously Operating Reference Stations (CORS), recorded in March 2010 during severe weather in the Victoria State, in southern Australia, sensitivity and statistical results of GPS tomography retrievals (water vapour density and wet refractivity) from 5 models have been tested and verified – considering independent observations from radiosonde and radio occultation profiles. The impact of initial conditions, associated with different time-convergence of tomography inversion, can reduce the normalised RMS of the tomography solution with respect to radiosonde estimates by a multiple (up to more than 3). Thereby it is illustrated that the quality of the apriori data in combination with iterative processing is critical, independently of the choice of the tomography model. However, the use of data stacking and pseudo-slant observations can significantly improve the quality of the retrievals, due to a better geometrical distribution and a better coverage of mid- and low-tropospheric parts. Besides, the impact of the uncertainty of GPS observations has been investigated, showing the interest of using several sets of data input to evaluate tomography retrievals in comparison to independent external measurements, and to estimate simultaneously the quality of NWP outputs. Finally, a comparison of our multi-model tomography with numerical weather prediction from ACCESS-A model shows the relevant use of tomography retrieval to improve the understanding of such severe weather conditions, especially about the initiation of the deep convection.
Static behavior of weighing cells
Authors: Darnieder Maximilian , Pabst Markus , Wenig Ronny , Zentner Lena , Theska René , Fröhlich Thomas
Published: November 2018

Abstract. Compliant mechanisms in precision weighing technology are highly sensitive
mechanical systems with continuously rising demands for performance in terms
of resolution and measurement uncertainty. The systematic combination of
adjustment measures represents a promising option for the enhancement of
weighing cells which is not yet fully exhausted. A novel adjustment concept
for electromagnetic force compensated weighing cells designed for 1 kg mass
standards is introduced. The effect on the mechanical behavior is analyzed in
detail using a planar compliant mechanism with semi-circular flexure hinges.
Design equations for a first layout of the mechanical system are derived from
a linearized rigid body model. Existing adjustment concepts for the stiffness
characteristic and the sensitivity to quasi-static ground tilt are included.
They are extended by the novel approach to attach trim weights to the levers
of the linear guide. Based on this concept, an optimal design for the
weighing cell is determined. The comparison with a finite element model
reveals further effects given by the more precise description of the
mechanical behavior. By parametric studies of the adjustment parameters in
the mechanical models, it is shown that the stiffness and tilt sensitivity
can be reduced significantly compared to the non-adjusted weighing cell. The
principal correlation of the trim weights and their effect on the mechanical
properties is experimentally verified using a commercially available weighing cell.
Submesoscale dispersion of surface drifters in a coastal sea near
offshore wind farms
Authors: Callies Ulrich , Carrasco Ruben , Floeter Jens , Horstmann Jochen , Quante Markus
Published: November 2018

Abstract. We analyse relative dispersion of surface drifters released as pairs (6 instances) or triplets (2 instances) during three field experiments in the German Bight in close proximity to wind farms. Drifter pairs can be classified in a remarkably clear way into those with spatial separation growing either exponentially or non-monotonously. There is some tentative evidence that exponential relative dispersion growth rates preferably occur for drifter pairs that are most exposed to the possible influence of a wind farm. Kinetic energy spectra and velocity structure functions suggest that turbulent energy could be injected by tides, possibly also via an interaction between tidal currents and wind turbine towers. Applicability of inertial range turbulence theory, however, can be doubted given distinct peaks of overtides observed in velocity power spectra. More comprehensive studies would be needed to better separate submesoscale effects of wind farms, tides and possibly baroclinic instabilities on observed drifter behaviour in a complex coastal environment.
An estimate of ice wedge volume for a High Arctic polar desert environment, Fosheim Peninsula, Ellesmere Island
Authors: Bernard-Grand'Maison Claire , Pollard Wayne
Published: November 2018

Abstract. Quantifying ground-ice volume on a regional scale is necessary to assess the
vulnerability of permafrost landscapes to thaw-induced disturbance like terrain subsidence and to
quantify potential carbon release. Ice wedges (IWs) are a ubiquitous
ground-ice landform in the Arctic. Their high spatial variability makes
generalizing their potential role in landscape change problematic. IWs form
polygonal networks that are visible on satellite imagery from surface
troughs. This study provides a first approximation of IW ice volume for the
Fosheim Peninsula, Ellesmere Island, a continuous permafrost area
characterized by polar desert conditions and extensive ground ice. We perform
basic GIS analyses on high-resolution satellite imagery to delineate IW
troughs and estimate the associated IW ice volume using a 3-D subsurface
model. We demonstrate the potential of two semi-automated IW trough
delineation methods, one newly developed and one marginally used in previous
studies, to increase the time efficiency of this process compared to manual
delineation. Our methods yield acceptable IW ice volume estimates, validating
the value of GIS to estimate IW volume on much larger scales. We estimate
that IWs are potentially present on 50 % of the Fosheim Peninsula (∼3000 km2), where 3.81 % of the top 5.9 m of permafrost could be
IW ice.
Modeling Sea Ice fracture at very high resolution with VP rheologies
Authors: Ringeisen Damien , Hutter Nils , Losch Martin , Tremblay L. Bruno
Published: November 2018

Abstract. Recent high resolution pan-Arctic sea ice simulations show fracture patterns (Linear Kinematic Features – LKFs) that are typical of granular materials but with intersection (fracture) angles wider than those observed from high-resolution satellite images (with a modal value of θ = 20°). In this article, We investigate the mechanism of formation and parameter dependencies of ice fracture in simple numerical bi-axial test on a 8 km x 25 km ice floe at an unprecedented resolution of 25m for two different yield curves: an elliptical (VP) and a Coulombic yield curve both with normal flow rule. In the standardVP model, the simulated angle of fracture is θ = 33.9°, compared to 20° in observations. The dependence of the angle of fracture on the ice shear strength is also contrary to that of typical granular materials with larger angle of fracture for higher shear strength – think of a wet sand castle with steeper walls than a dry sand castle. In this model, the divergence along the fracture lines (or LKFs) is entirely dictated by the ice shear strength used in the model with high shear strength resulting in convergence along LKFs and low shear strength resulting in divergence along LKFs. This is again contrary to typical granular materials where divergence (or dilation) is linked with the orientation of contacts normals that oppose the flow with divergence present for larger shear resistance and convergence for lower shear resistance. Moreover, the angle of fracture depends on the confining pressure in the uni-axial test with more convergence as the confining pressure increases, again contrary to granular material that have an angle of fracture that is independent of the confining pressure. We note that all three behaviors of the VP model are linked with the use of an associative (normal) flow rule. In the Coulombic model, the angle of fracture is smaller (θ = 23.5°), but the solution is unstable when the compressive stresses are too large because of the discontinuity between the straight limbs of the yield curve and the elliptical capping. Our results show that while the VP model gives angles of fracture that are visually correct, the bias in the magnitude of the angle of fracture and the physical dependencies of the angle of fracture on mechanical strength parameters and stress fields couple the sea ice mechanical strength parameters, the sea-ice drift, sea-ice deformation (strain-rate) field in an inconsistent way. We consider this evidence to move away from the elliptical yield curve and associative (normal) flow rule, a deformation law that is not applicable to pressure-sensitive and dilatant granular material such as sea ice.
SENYVO AMŽIAUS MOTERŲ FIZINIO AKTYVUMO, GYVENIMO KOKYBĖS IR SUBJEKTYVIOS GEROVĖS YPATUMAI BEI SĄSAJOS
Authors: Černovas Andrejus , Alekna Vidmantas , Tamulaitienė Marija , Katavičiūtė Greta , Stukas Rimantas
Published: November 2018

Tyrimo tikslas – ištirti 60 metų ir vyresnio amžiaus moterų fizinio aktyvumo, gyvenimo kokybės ir su­bjektyvios gerovės ypatumus bei tarpusavio sąsajas. Tyrimo medžiaga ir metodai. Vienmomentis skers­pjūvio tipo tyrimas atliktas 2017 m. rugsėjo-gruodžio mėn. Tiriamųjų apklausa buvo vykdoma tiesiogiai, naudojant bendrąjį ir specialiuosius klausimynus. Bendrajame klausimyne buvo registruojami socio­demografiniai duomenys, ūgis, kūno masė, apskai­čiuotas kūno masės indeksas. Specialieji klausimynai buvo skirti įvertinti senyvo amžiaus moterų fizinį aktyvumą (angl. Physical Activity Scale for Elderly, PASE), gyvenimo kokybę (angl. Control, Autonomy, Self-realization, Pleasure, CASP-19) ir subjektyvią gerovę (angl. Positive and Negative Affect Schedule, PANAS; angl. Satisfaction With Life Scale, SWLS). Statistinė duomenų analizė atlikta naudojant SPSS 18.0 for Windows programų paketą. Rezultatai. Tyrime dalyvavo 103 moterys, kurių vidu­tinis amžius – 71,37±7,58 metai. Didžiąją tiriamųjų dalį sudarė miesto gyventojos, turinčios aukštąjį išsi­lavinimą, daugiau nei pusė jų gyveno vienos. PASE, CASP-19 (kontrolės, autonomijos sritys), PANAS-PA ir PANAS-NA klausimynų vidutiniai įverčiai statistiš­kai reikšmingai skyrėsi 60–69 m., 70–79 m. ir 80 m. ir vyresnio amžiaus grupėse. CASP-19 klausimyno kontrolės srities vidutiniai įverčiai buvo mažiausi našlių moterų grupėje, aukščiausi – neištekėjusių arba išsiskyrusių moterų grupėje. PASE, CASP-19 klausi­myno autonomijos srities vidutiniai įverčiai didesni aukštąjį išsilavinimą turinčių moterų grupėje, taip pat jos jaučia daugiau teigiamų (PANAS-PA) ir mažiau neigiamų (PANAS-NA) emocijų, nei moterys su ma­žesniu išsilavinimu. Fizinis aktyvumas vidutiniškai stipriai koreliavo su teigiamo emocingumo vidutiniais įverčiais. Nustatyti vidutinio stiprumo koreliaciniai ryšiai tarp gyvenimo kokybės ir subjektyvią gerovę vertinančių klausimynų vidutinių įverčių. Išvados. 1. Mūsų tyrimo rezultatai parodė, kad 80 m. ir vyresnio amžiaus moterų fizinis aktyvumas mažes­nis, gyvenimo kokybė blogesnė, jos patyrė mažiau teigiamų ir daugiau neigiamų emocijų, negu jaunes­nės (60–79 m.) senyvo amžiaus moterys. Mieste gy­venančių, aukštąjį išsilavinimą turinčių moterų fizinis aktyvumas buvo didesnis, jos patyrė daugiau teigiamų ir mažiau neigiamų emocijų negu gyvenančios kaime. Mieste gyvenančių moterų gyvenimo kokybė buvo geresnė nei gyvenančių kaime. 2. Senyvo amžiaus moterų fizinis aktyvumas stipriai susijęs su teigiamu emocingumu, gyvenimo kokybė – su teigiamu emo­cingumu ir pasitenkinimu gyvenimu. Pasitenkinimas gyvenimu buvo susijęs su savęs realizavimo sritimi.
INTRAAUDININĖ BRACHITERAPIJA ONKOGINEKOLOGIJOJE. NACIONALINIO VĖŽIO INSTITUTO PATIRTIS
Authors: Nevulis-Obuchovska Violeta , Janulionis Ernestas
Published: November 2018

Spindulinė terapija yra vienas pagrindinių gydymo metodų pacientėms, sergančioms ginekologinės sri­ties piktybinėmis ligomis. Brachiterapijos principas – jonizuojančios spinduliuotės šaltinio įterpimas į naviką arba šalia jo. Naudojant standartinius aplika­torius nevisada pasiekiama radikali gydomoji dozė ir tuomet svarstoma galimybė taikyti intraaudininę brachiterapiją. Klinikinių tyrimų duomenimis, paci­entėms, sergančioms gimdos kaklelio vėžiu, chemo-spindulinis gydymas ir vaizdais valdoma intraaudi­ninė brachiterapija gerina lokalią naviko kontrolę ir bendrą išgyvenamumą. Straipsnyje pateikta klinikinių tyrimų, kuriuose buvo taikyta intraaudininė brachi­terapija, apžvalga ir įvardintos svarbiausios indika­cijos, apžvelgti brachiterapijos aplikatorių tipai bei planavimo ypatumai. 2017 m. Nacionaliniame vėžio institute pradėta taikyti intraaudininė brachiterapija moterims, sergančioms onkoginekologinės srities na­vikais. Nedidelė pacienčių imtis, jų klinikinių atvejų įvairovė bei trumpas laikotarpis nuo gydymo pabai­gos kol kas leidžia vertinti ankstyvųjų spindulinių reakcijų pasireiškimą. Pateiktas klinikinis atvejis, rodantis intraaudininės brachiterapijos pranašumą, ly­ginant su brachiterapija naudojant standartinius apli­katorius: vertinant dozės pasiskirstymą navike ir kri­tinių organų apsaugą. Intraaudininės brachiterapijos gydymo metodas yra įtrauktas į Nacionalinio vėžio instituto onkoginekologinių navikų gydymo gaires.
The Human Rights Climate in Higher Education Institutions in Jordan
Authors: Al-Sharah Naser , Khlaif Al-Sharaah Faisal
Published: November 2018

This study aimed to uncover the reality of the human rights climate in higher education institutions in Jordan. It used the descriptive survey approach and applied the University of Minnesota Scale (Taking the Human Rights Temperature of Your School). The study sample consisted of (521) male and female students and teachers. Results showed that the impact of the human rights climate is present at higher education institutions in Jordan at a medium degree of (3.14) and a standard deviation of (0.39). They’ve also shown that there are no statistically significant differences at the level of significance (α ≤ 0.05) regarding the impact of the human rights climate on higher education institutions in Jordan due to the variables of role (students, teachers) and gender (male, female).