bluuebunny/crossref_metadata_2025 huggingface dataset:
Chitosan: An elicitor and antimicrobial Bio-resource in plant protection
Authors: Singh Akansha , Gairola, Kalpana , Upadhyay Vinod , Kumar J.
Published: April 2018

Pesticide resistance and environment threat due to injudicious use of chemical pesticides for disease management employs the alteration in management practices. Chitosan, a deacetylated chitin derivative, behaves like a general elicitor, inducing a non-host resistance, and prime the plants for systemic acquired resistance in addition to this Chitosan has high antimicrobial activity against a wide range of pathogenic and spoilage microorganisms, including fungi and bacteria. The use of chitosan in agriculture and in food systems should be based on sufficient knowledge of the complex mechanisms of its elicitor and antimicrobial mode of action. In this article we a number of studies on the investigation of chitosan antimicrobial and resistance inducing properties and application of them in agriculture sector have been summarized.
Hemofagositik lenfohistiyositoz hastalarında kraniyal MRG bulguları
Authors: ERASLAN Cenk , AYDIN Elçin , MAHARRAMOVA Eltan , ŞAHİN Akkız , HEKİMCİ ÖZDEMİR Hamiyet , YILMAZ KARAPINAR Deniz , ÇALLI Cem , KİTİŞ Ömer
Published: April 2018

Amaç: Hemofagositik lenfohistiyositoz (HLH) kontrolsüz immün yanıta yol açan hiperinflamasyonla karakterize klinik bir sendromdur. Etiyolojiye bağlı primer ve sekonder olarak sınıflanmaktadır. Klinik bulguları arasında ateş, splenomegali, hepatit yer almaktadır. Tanı doku örneklenmesi ile konulur. Familyal HLH’li hastaların santral sinir sistemi (SSS) tutulumu hastalığın prognozunu ve klinik gidişini olumsuz etkileyen bir faktördür. SSS tutulumunun bulguları; progresif ensefalopati, irritabilite, nöbet, kraniyal sinir paralizisi, ataksi, nistagmus, yürüme ve görme bozukluğu, psikomotor gelişim geriliğidir. Bu çalışmada, SSS tutulumu olan 6 olgunun radyolojik görüntüleme bulgularını sunmayı amaçladık.Gereç ve Yöntem: Bir-onbir yaş aralığında 6 hasta irritabilite, nöbet, ataksi, nistagmus, yürüme ve görme bozukluğu, psikomotor gelişim geriliği gibi nörolojik bulgularla hastanemize baş vurdu ve nörolojik muayene sonrasında kranyal manyetik rezonans görüntüleme (MRG) incelemesi gerçekleştirildi.Bulgular: Hastalarımıza klinik ve laboratuvar değerlendirmeleri sonrasında yapılan kemik iliği biyopsisi ile HLH tanısı konuldu. Hastalarımızın tamamında SSS tutulumunu gösteren kraniyal MRG bulguları saptandı. MRG incelemesinde T2 ağırlıklı ve FLAIR sekanslarında serebral hemisferlerde hiperintens odaklar ve postkontrast serilerde patolojik kontrastlanma ortak bulgular olarak belirlendi.Sonuç: HLH hastalığının santral sinir sistemi tutulumu yüksek mortalite ve morbidite ile seyretmektedir. Kraniyal MRG SSS tutulumunu göstermede önemli rol oynamaktadır.
Deforme biliyer metal stente bağlı gelişen gastrointestinal sistem kanaması
Authors: AKPINAR Muhammet Yener , SAYGILI Fatih , ÖZTAŞ Erkin , COŞKUN Orhan , ÖDEMİŞ Bülent
Published: April 2018

Kanama, endoskopik retrograd kolanjiyopankreatografinin (ERCP) ciddi komplikasyonlarından biri olup insidansı %1-2 arasında değişir. Kanama sıklıkla endoskopik sfinkterotomi ile ilişkilidir, bununla beraber vaka serilerinde sfinkterotomi ilişkisiz kanamalar da bildirilmiştir. Biliyer metal stentin barsak duvarında yaptığı irritasyona bağlı oluşan kanamalar sfinkterotomi ilişkisiz kanamalara örnek gösterilebilir. Biliyer stent öyküsü olan hastaların stentin olduğu yerde ağrı ile gelmesi stentin barsak duvarına yaptığı irritasyonu akla getirir. Literatürde migre olmadan deformasyonla barsak duvarı irritasyonu yapan ve kanamaya yol açan biliyer metal stent görülmemiştir. Burada öncesinden ERCP ile biliyer metal stent konulan ve metal stentin deformasyonuna bağlı duodenumda oluşan ülserin yol açtığı kanama ile gelen hastamızı sunduk.
Çocuklarda ofis kan basıncı parametreleri ile ayaktan kan basıncı monitörizasyonu (AKBM) sonuçlarının karşılaştırılması: Güncellenmiş AKBM raporuna göre olguların değerlendirilmesi
Authors: ÇELEBİ TAYFUR Aslı , ONAT GÖKÇE Ece , BÜYÜKKARAGÖZ Bahar , ÇALTIK YILMAZ Aysun , ALTUNTAŞ Nilgün , BULUŞ Ayşe Derya
Published: April 2018

Amaç: Günümüzde çocukluk çağında obezitenin yaygınlaşmasıyla birlikte hipertansiyon görülme sıklığı artmaktadır. Ayaktan (ambulatuvar) kan basıncı (KB) monitörizasyonu (AKBM) hedef organ hasarı riskini ofis ölçümünden daha iyi öngörmektedir. Bu çalışmada KB yüksekliği nedeni ile izlenen olguların ofis KB parametreleri ile AKBM sonuçlarının karşılaştırılması ve Amerikan Kalp Birliği’nin 2014 yılında güncellediği çocuklarda AKBM raporuna göre olguların değerlendirilmesi amaçlanmıştır. Gereç ve Yöntem: Ofis KB değerleri yüksek bulunan (>90 persentil) ve AKBM uygulanan olguların kayıtları retrospektif olarak incelendi. İkincil hipertansiyonu olan veya AKBM sırasında antihipertansif ilaç kullanmakta olan hastalar çalışma dışında tutuldu. Olguların ofis KB ve AKBM sonuçları Amerikan Kalp Birliği’nin 2014’de güncellediği çocuklarda AKBM raporuna göre evrelendirildi. Olguların demografik bilgileri, vücut kitle indeksi (VKİ), VKİ-standart deviasyon skoru (SDS) ve AKBM sonuçları istatistiksel olarak karşılaştırıldı. Bulgular: Çalışmaya 31 erkek, 26 kız olgu alınmış olup, olguların yaş ortalaması 14.42±2.14 yıldı. Ofis KB ve AKBM sonuçlarına göre, olguların %63’ünde (n=36) beyaz önlük hipertansiyonu, %15.7’inde (n=9) ambulatuvar hipertansiyon, % 12.2’sinde (n=7) ciddi ambulatuvar hipertansiyon, %5.3’ünde (n=3) prehipertansiyon ve %3,5’inde (n=2) maskelenmiş hipertansiyon saptandı. Prehipertansiyonu olan olguların 2’sinde (n=2/3, %66.7) ve ambulatuvar hipertansiyonu olan olguların 10’unda (n=10/18, %55) obezite mevcuttu. Yirmi dört saatlik ortalama sistolik ve diyastolik KB arasında pozitif korelasyon belirlendi. Olgularda VKİ ile 24 saatlik ortalama sistolik KB, gece sistolik KB ve 24 saatlik ortalama arter basıncı değerleri arasında da pozitif korelasyon saptandı. Sonuç: Ofis KB yüksek olan ve hipertansiyon için risk faktörü taşıyan çocukların izleminde AKBM uygulaması önerilir.
Lokal ileri evre serviks kanserlerinde yoğunluk ayarlı radyoterapi ve volumetrik ayarlı ark tedavinin dozimetrik karşılaştırılması
Authors: NALBANT Berna , SERT Fatma , TAVLAYAN Emin , OLACAK Nezahat , ÖZSARAN Zeynep
Published: April 2018

Amaç: Radyokemoterapi lokal ileri evre serviks kanserinin tedavisinde standart yaklaşımdır. Amacımız, serviks
kanseri tedavisinde modern tekniklerden yoğunluk ayarlı radyoterapi (YART) ve volumetrik ark terapi (VMAT)
tekniklerini dozimetrik olarak karşılaştırmaktır.
Gereç ve Yöntem: Kliniğimizde tedavi edilmiş 10 lokal ileri evre serviks kanseri hastasının bilgisayarlı tomografi
(BT)’leri kullanılmıştır. Hastalarda gross tümör hacmi (GTV), klinik tümör hacmi (CTVtm) ve lenf nodları (CTV lenf
nodu) ve komşu risk altındaki organları konturlanmıştır. CTVtm ve CTV lenf nodlarına 1.5 cm sınır verilerek tedavi
hacimleri oluşturulmuştur. Total doz 50.4 Gy olacak şekilde günlük 1.8 Gy fraksiyon dozu ile tedavi planlamaları
yapılmıştır. İki teknik, Doz volüm histogramı, homojenite indeks (HI), konformite indeks (KI), monitör ünit (MU),
segment sayısı değerlendirmeleri yapılmıştır.
Bulgular: İnce bağırsak için, 40 Gy doz alan hacim yüzdeliğinin YART tekniğinde medyan değeri %14.24 iken,
VMAT tekniğinde %11.28 olarak hesaplanmıştır (p=0.022). VMAT tekniğinde %12.39 olarak hesaplanan femur
başları 30 Gy doz alan hacim değerleri, YART tekniğinde ortanca değeri %7.80 olarak bulunmuştur (p=0.007). VMAT
tekniği istatistiksel anlamlı seviye kısa sürede tamamlanırken, fraksiyon başına MU değeri anlamlı olarak fazla
bulunmuştur. Her iki tedavi tekniğinin de HI ve KI değerleri açısından aralarında farklılık gösterilememiştir.
Sonuç: Hasta konforuna ve cihaz performansına açısından VMAT tekniğinde kısa tedavi süresi avantaj olarak
görülmektedir. Kliniğimizin mevcut cihaz durumuna göre her iki tedavi modeli de kullanılabilir
Efecto inhibidor in vitro del extracto etanólico de propóleo al 15% y 30% frente a cepas de Lactobacillus acidophilus
Authors: Huaytalla Alemán Richard M. , Gálvez Ramírez Carlos M. , Carhuapoma-Yance Mario , Alvarez-Paucar María A. , López Guerra Sofía
Published: April 2018

Objetivos: Determinar la efi cacia in vitro del efecto inhibidor del extracto etanólico de propóleo en comparación al gluconato de clorhexidina frente a cepas de Lactobacillus acidophilus. Material y Métodos: El tipo de investigación fue experimental, prospectivo, analítico y longitudinal, llevándose a cabo en el laboratorio de microbiología de la Universidad Privada Norbert Wiener durante el año 2016. La población estuvo conformada por cepas de Lactobacillus acidophilus de uso comercial, con una muestra de 30 cultivos en placas petri con agar base sangre, colocándose discos de papel Whatman N° 40 embebidos con extracto etanólico de propóleo al 15% y 30%, así como gluconato de clorhexidina 0,12% como control positivo y alcohol de 70° como control negativo. Se desarrolló el cultivo en condiciones de anaerobiosis a 37 °C. Resultados: Se obtuvo que la concentración al 15% y 30% del extracto etanólico de propóleo presenta un mayor efecto inhibidor promedio de 8,15 mm y 11,75 mm a las 48 horas y de 11,40 mm y 14,25 mm a las 72 horas, respectivamente; en relación al halo de inhibición promedio producido por el gluconato de clorhexidina al 0,12% a las 48 y 72 horas, que fue de 6,55 mm y 8,00 mm. Conclusiones: Elextracto etanólico de propóleo al 30% es más efectivo in vitro que la clorhexidina al 0,12% para el control de Lactobacillus acidophilus.
A Perspective on the Application of Spatially Resolved ARPES for 2D Materials
Authors: Cattelan Mattia , Fox Neil
Published: April 2018

In this paper a perspective on the application of spatially- and Angle- Resolved PhotoEmission Spectroscopy (ARPES) for the study of two-dimensional (2D) materials is presented. ARPES allows the direct measurement of the electronic band structure of materials generating extremely useful insights into their electronic properties. The possibility to apply this technique to 2D materials is of paramount importance because these ultrathin layers are considered fundamental for future electronic, photonic and spintronic devices. In this review an overview of the technical aspects of spatially localized ARPES is given along with a description of the most advanced setups for laboratory and synchrotron-based equipment. This technique is sensitive to the lateral dimensions of the sample, therefore a discussion on the preparation methods of 2D material is presented. Some of the most interesting results obtained by ARPES are reported in three sections including: graphene, transition metal dichalcogenides (TMDCs) and 2D heterostructures. Graphene has played a key role in ARPES studies because it inspired the use of this technique with other 2D materials. TMDCs are presented for their peculiar transport, optical and spin properties. Finally, the section featuring heterostructures highlights a future direction for research into 2D material structures.
Potential Animal Reservoir of Mycobacterium ulcerans: Systematic Review
Authors: Singh Avishek , McBride John , Govan Brenda , Pearson Mark
Published: April 2018

Mycobacterium ulcerans is the causative agent of the Buruli ulcer, also known, in Australia, as Daintree ulcer or Bairnsdale ulcer. This destructive skin disease is characterized by extensive and painless necrosis of the skin and soft tissue with the formation of large ulcers, commonly on the leg or arm. To date, 33 countries with tropical, subtropical and temperate climates in Africa, the Americas, Asia and the Western Pacific have reported cases of Buruli Ulcer. The disease is rarely fatal, although it may lead to permanent disability and/ or disfigurement if not treated appropriately or in time. It is the third most common mycobacterial infection in the world after tuberculosis and leprosy. The precise mode of transmission of M. ulcerans is yet to be elucidated. Nevertheless, it is possible that the mode of transmission varies with different geographical areas and epidemiological settings. The knowledge about the possible route of transmission and potential animal reservoir of M. ulcerans is poorly understood and still remains patchy. We conducted a systematic review with selected key words on PubMed and INFORMIT databases to aggregate available published data on animal reservoirs of M. ulcerans. After certain inclusion and exclusion criteria, a total of 17 studies were included in the review. A variety of animals, e.g rodents, shrews, possums (ringtail and brush tail), horses, dogs, alpacas, koalas and Indian flap-shelled turtles have been recorded as being infected with M. ulcerans around the world. The majority of studies included in this review identified animal reservoirs, either aquatic or terrestrial, as predisposing for the emergence and reemergence of M. ulcerans infection. Taken together, the selected studies in this systematic review and discussed so far, it is clear that exotic wildlife, aquatic animals and native mammals play a significant role as reservoirs for M. ulcerans.
New Synchronous Machine Rotor Design for Easy Insertion of Excitation Coils Based on Surrogate optimization
Authors: Yuan Tiejiang , Yang Nan , Cao Wenping , Tan Zheng , Li Guofeng , Song Xueguan
Published: April 2018

This paper introduces a new rotor design for the easy insertion and removal of the rotor windings. The shape of the rotor is optimized based on surrogate method in order to achieve the lowest power loss under the maximum power output. The performance of the new rotor is examined in 2-D finite element software and validated by experiments. This rotor shows good potentials for reducing the maintenance and repair costs of synchronous machines, making it suitable for manufacturers within the mass production markets such as gen-sets, steam turbines, wind power generators and hybrid electric vehicles.
High Step-up Modular Switched-Capacitor DC-DC Converter with Fault Tolerance Capability
Authors: He Zhengzhao , Yuan Tiejiang , Cao Wenping , Lin Zhengyu
Published: April 2018

A modular switched-capacitor (SC) DC-DC converter (MSCC) is introduced in this paper. It is designed to boost a low input voltage to a high voltage level and can be applied for photovoltaics and electric vehicles. This topology has high extensibility for high voltage gain output. The merits of the converters also lie in the fault tolerance operation and the voltage regulation with a minimum change in the duty ratio. Those features are built in when designing the modules and then integrating these into the DC-DC converter. Converter performance including voltage gain, voltage and current stress are focused and tested. The converter is modelled analytically, and its control algorithm is analyzed in detailed. Both simulation and experiment are carried out to verify the topology under normal operation and fault mode operation.
Direct Exfoliation of g-C3N4 with Addition of NaOH for Enhanced Photocatalytic Cr(Ⅵ) Reduction
Authors: Guo Yaping , Sun Jianyang , Chang Hui , Zhao Xu
Published: April 2018

A simple, effective and environmental-friendly method was adopted for enhancing the photocatalytic activity of g-C3N4 in the reduction of aqueous Cr(Ⅵ) under visible-light irradiation. The enhancement was achieved via treatment of g-C3N4 in organic solvent with addition of NaOH particles by ultrasonic process for two hours. The results demonstrated that the treated g-C3N4 exhibited much higher photocatalytic activity than pristine g-C3N4 in the reduction of Cr(VI) . Under visible light irradiation for 120 min, the reduced ratios of Cr(VI) with the initial concentration of 50 mg/L in the presence of the treated g-C3N4and pristine g-C3N4 were 100% and 37.1%, respectively. With the addition of fulvic acid, Cr(VI) was efficiently removed at 40 min. Based on the characterization results of the structures and other physiochemical properties of the treated g-C3N4 and pristine g-C3N4 by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and UV Vis diffuse reflectance, the possible reasons responsible for the enhanced photocatalytic activity of the treated g-C3N4 were proposed. The yield and mechanism of different exfoliation methods were compared by semi-quantitative method.
Multilevel Factors Affecting the Route Decision for Foraging in the Generalist ant Pheidole oxyops
Authors: Assis Diego Santana , Camargo Giovanni Abrami Rodrigues , Nascimento Fabio Santos do
Published: April 2018

Pheidole oxyops Forel, 1908 is a generalist ant, which forages actively for plant debris to dead arthropods. In addition, its nest has an entrance that allows the ants gather resources passively by capturing falling preys into the nest. Our objective was to verify if different day periods, temperature and residual soil accumulation (ground pile in the side of nest entrance) could influence the patterns of foraging activity. Foraging activities were registered in the morning, afternoon and twilight. We measured direction and vector of trails, air temperature and humidity during foraging events. Our results showed that foraging routes are independent of residual soil accumulation and other nearby nests. However, air temperature and the time daily period are significant factors to foragers’ exits. Higher air temperatures influenced negatively the exits. In the period of the afternoon, the ants do not show any preference for routes, different from the morning and twilight. In addition, foraging activities were significantly more frequent during twilight period. Leaving the nest at twilight could allow ants foraging in an environment with less exposition to potential predators and competitors. Moreover, it may be also related to opportunism to hunt other nocturnal insects.
A High Resolution Coupled Fire-Atmosphere Forecasting System to Minimize the Impacts of Wildland Fires: Applications to the Chimney Tops II Wildland Event
Authors: Jiménez Pedro A. , Muñoz-Esparza Domingo , Kosović Branko
Published: April 2018

Wildland fires are responsible for large socio-economic impacts. Fires affect the environment, damage structures, threaten lives, cause health issues, and involve large suppression costs. These impacts can be mitigated via accurate fire spread forecast to inform the incident management team. We show that a fire forecast system based on a numerical weather prediction (NWP) model coupled with a wildland fire behavior model can provide this forecast. This is illustrated with the Chimney Tops II wildland fire responsible for large socio-economic impacts. The system is run at high horizontal resolution (111 m) over the region affected by the fire to provide a fine representation of the terrain and fuel heterogeneities and explicitly resolve atmospheric turbulence. Our findings suggest that one can use the high spatial resolution winds, fire spread and smoke forecast to minimize the adverse impacts of wildland fires.
Use of Nutritional Supplements in Amateur Tennis Players
Authors: Sánchez-Oliver Antonio Jesús , Mata-Ordoñez Fernando , Domínguez Raúl , López-Samanes Álvaro
Published: April 2018

Literature on the use of nutritional supplements (NS) in tennis players is scarce. The objective of the present study was to evaluate NS consumption in a group of men's tennis players who participated in the 2016 Andalusian team championship. A total of 70 questionnaires from 7 different clubs were registered. The questionnaire was previously designed and evaluated through piloting in which the validity of the content, its application, its structure and its presentation were observed. The results showed that 100% of the sample group was in favor of NS consumption within the law, 88.6% claimed to have consumed them at some time and 61.4% presently consume them. The NS most consumed by study participants were sports drinks (69.35%), energy bars (29%), a vitamin complex (19.35%), protein (serum) (17.74%) and creatine (14.51%). A high percentage of NS consumers thought that they had obtained positive results from NS consumption. The percentages and the findings regarding NS consumption in the present study were similar to the contributions made by other studies which evaluated supplementation in athletes, although with some subtle differences.
Motion Sensor Application on Building Lighting Installation for Energy Saving and Carbon Reduction Joint Crediting Mechanism
Authors: Riyanto Indra , Margatama Lestari , Hakim Hakim , Martini Martini , Hindarto Dicky Edwin
Published: April 2018

High electricity demand for consumption at current supply level in Indonesia led to the rising cost of electricity bills. This factor is compounded by the fact that many electric generators in Indonesia still use fossil fuels, which contributes to the high basic generation cost. UBL is one of the universities that aim to be a green campus. Our research explores the possibility of installing motion sensor to contribute on the energy efficiency. Although mostly common in developed countries, the use of motion sensor for energy efficiency is still rare, especially in Indonesia. despite rising cost and supply shortages, Indonesian buildings are still of high energy consumption. our experiment shows that simple installation of commercially available motion sensors can contribute to reduce the electricity bill from the increase of energy efficiency. One of the efforts to lower energy demand in consumer side is to use the electricity efficiently, such as turning off lights in a room when it's not in use. This method can be simply done by turning the light switches for office and classrooms, but difficult to do in public spaces such as toilets and corridors. Our experiment shows that simple installation of commercially available motion sensors can contribute to reduce the electricity bill from the increase of energy efficiency. Automatic light switches experimentally installed in sample toilet room prove that electricity consumption from the lamps can contribute to the reduction of total weekly energy that translates into Green House Gas emission reduction.
One-Stop Dispensing: Hospital Costs and Patient Perspectives on Self-Administration of Medication
Authors: Houlind Morten Baltzer , McNulty Helle Bach Oelgaard , Treldal Charlotte , Andersen Signe Lindegaard , Haupt Thomas Huneck , Petersen Janne , Andersen Ove , Kjeldsen Lene Juel
Published: April 2018

1) Objective: to assess staff time and hospital medication costs between One-Stop Dispensing (OSD) and the Traditional Medication System (TMS), and to evaluate patient perspectives on OSD. 2) Methods: The study was conducted at Hvidovre Hospital, University of Copenhagen, Denmark in an elective gastric surgery and acute orthopedic surgery department. The study was designed as an intervention study with a historical control group receiving TMS. The intervention group included adult patients able to self-administer medication. Time measurements included time used by nurses and pharmacy staff to dispense and administer medication as well as medication dialogue. Medication costs with two days of discharge medication were compared between OSD and TMS. Patient satisfaction related to OSD was evaluated by a questionnaire based on a five-point Likert scale ('very poor' (1) to 'very good' (5)). 3) Results: Seventy-eight elective and 70 acute patients were included. Compared with TMS, OSD significantly reduced used staff time by an average of 12 minutes (P < 0.0001) per patient per hospitalization. Overall, there was no significant increase in medication cost per patient for OSD (1.68 € [CI 95 -0.51―3.87]) (P = 0.13). Mean scores for the OSD satisfaction questionnaire ranged from 4.3―4.8. OSD was associated with significantly lower used staff time. 4) Conclusion: Staff time in OSD was significantly lower, there were no differences in medication costs and the patients were overall satisfied with OSD.
UAT ADS-B Data Anomalies and Effect of Flight Parameters in Dropout
Authors: Tabassum Asma , Semke William
Published: April 2018

An analysis of the performance of Automatic Dependent Surveillance-Broadcast (ADS-B) data received from the Grand Forks, North Dakota International Airport was carried in this study. The purpose was to understand the vulnerabilities of UAT ADS-B system and recognize the effects on present and future Air Traffic Control (ATC) operation. At present unmanned aircraft systems (UAS) and autonomous air traffic control (ATC) towers are being integrated into the aviation industry. As a fundamental component of future surveillance system, the anomalies and vulnerabilities of ADS-B system need to be identified to enable a fully utilized airspace with enhanced situational awareness. The anomaly detection of ADS-B messages was based on the Federal Aviation Administration’s (FAA) ADS-B performance assessment report. Data investigation revealed ADS-B message suffered from different anomalies including drop out; missing payload; data jump; low confident data and altitude discrepancy. Among all the anomalies detected message discontinuation or dropout was found to be most frequent. Considering the potential danger being imposed, an in-depth analysis was carried out to characterize message dropout. Three flight parameters were selected to investigate their effect on drop out. Statistical analysis identified that altitude affected drop out more than any other flight parameters.
Children’s Cortisol and Cell-Free DNA Trajectories in Relation to Sedentary Behavior and Physical Activity in School: A Longitudinal Analysis
Authors: Becker Christoph , Schmidt Sebastian , Neuberger Elmo , Kirsch Peter , Simon Perikles , Dettweiler Ulrich
Published: April 2018

Education outside the classroom (EOtC) can be beneficial for students. The relationship between biological stress markers and sedentary behavior (SB) plus physical activity (PA) is insufficiently evaluated in school settings. This exploratory study aims to evaluate the association between students’ cortisol, plus circulating cell-free deoxyribonucleic acid (cfDNA) levels, and their SB, light PA (LPA) and moderate-to-vigorous PA (MVPA) during outdoor and indoor classes in different seasons. We assessed data from an education outside the classroom (EOtC) program (n = 48; intervention group [IG], n = 37; control group [CG], n = 11). We sampled data on 3 school-days in three seasons (fall, spring, and summer) in normal teaching indoors (CG) and outdoor lessons (IG) in the forest. SB and PA were evaluated by accelerometry, and cortisol and cfDNA levels by saliva samples. The compositional data analysis approach analyzed SB and PA. Fitted Bayesian hierarchical linear models evaluated the association between cortisol and cfDNA, and SB/LPA/MVPA. A steady decline of cortisol in the outdoor setting is associated with relatively high levels of LPA. SB and MVPA tended to exhibit a similar effect in the indoor setting. CfDNA is positively associated with a relatively high amount of SB in the IG, the same association is likely for LPA and MVPA in both groups. LPA seems to support a healthy cortisol decrease in children during outdoor lessons. The relevance of SB/PA as a composition in relation to students stress response in school should be emphasized. This study facilitates the formulation of straightforward and directed hypotheses for further research.
Experimental Study and Modeling of Ground-Source Heat Pumps with Combi-Storage in Buildings
Authors: El-Baz Wessam , Tzscheutschler Peter , Wagner Ulrich
Published: April 2018

There is a continuous growth of heat pump installations in residential buildings in Germany. The heat pumps were not only used for space heating and domestic hot water consumption but also to offer flexibility to the grid. the high coefficient of performance and the low cost of heat storages made the heat pumps an optimal candidate for the power to heat applications. Thus, several questions are raised about the optimal integration and control of the heat pump system with buffer storages to maximize its operation efficiency and minimize the operation costs. In this paper, an experimental investigation is performed to study the performance of a ground source heat pump (GSHP) with a combi-storage under several configurations and control factors. The experiments were performed on an innovative modular testbed that is capable of emulating a ground source to provide the heat pump with different temperature levels at different times of the day. Moreover, it can emulate the different building loads such as the space heating load and the domestic hot water consumption in real-time. The data gathered from the testbed and different experimental studies were used to develop a simulation model based on Modelica that can accurately simulate the dynamics of a GSHP in a building. The model was validated based on different metrics. Energetically, the difference between the developed model and the measured values was only 3.08\% and 4.18\% for the heat generation and electricity consumption, respectively.
IMPLEMENTASI PERANGKAT PEMBELAJARAN BERBASI MASLAAH YANG MEMANFAATKAN SUMBER BELAJAR AUTENTIK PADA PELAJARAN MATEMATIKA SD
Authors: Talib Ahmad
Published: April 2018

This research is development research Development procedure that used in this research is Thiagarajan model or four D model Data analysis describe the result as: (1) Teachers ability level (degree) in managing learning process by using problem based learning that make use of authentic learning source involve in high category, it means teachers’ performance can be maintained, (2) Teacher can guide grop for working and studying, (3) Commonly, student gives positive response towards learning device that used, (4) learning device of mathematics problem based models making use of authentic learning source make student more active in learning process, and (5) The average score students achieved on the achievement test is 78.06 from ideal score 100 with standard deviation 20.92. Where 25 from 31 students or 80.64% fulfilled individual completeness showing that classical completeness achieved.

Abstrak

Penelitian ini adalah penelitian pengembangan (Reseacrh and Development). Prosedur pengembangan digunakan dalam penelitian ini adalah model Thiagarajan atau model 4D (Define, Design, Develop, dan Disseminate). Analisis data menggambarkan hasil sebagai berikut: (1) tingkat kemampuan guru dalam mengelola prses pembelajaran dengan menggunakan perangkat pembelajaran berbasis masalah yang memanfaatkan sumber belajar autentik termasuk dalam kategori tinggi, artinya penampilan guru dapat dipertahankan; (2) guru dapat membimbing kelompok untuk bekerja dan belajar; (3) pada umumnya siswa memberikan respon yang positif terhadap perangkat pembelajaran yang digunakan; (4) perangkat pembelajaran Matematika model berbasis masalah yang memanfaatkan sumber belajar autentik menjadikan siswa lebih aktif dalam proses pembelajaran; dan (5) skor rata-rata yang diperoleh siswa pada test hasil hasil belajar adalah 78,06 dan skor ideal 100 dengan standar deviasi 20,92. Di mana 25 dari 31 siswa atau 80,64% memenuhi ketuntasan individu yang menunjukkan bahwa ketuntasan klasikal tercapai
KARAKTERISTIK SERAPAN UAP AIR DAN FTIR DARI BIOKOMPOSIT PATI TAPIOKA DIPERKUAT SERAT AKAR BUAH NAGA (HYLOCEREUS POLYRHIZUS)
Authors: Asrofi Mochamad , Abral Hairul , Kasim Anwar , Pratoto Adjar , Mahardika Melbi
Published: April 2018

Abstrak

Biokomposit dari pati tapioka dan serat akar buah naga telah berhasil dibuat. Sebanyak 0, 2, 4, dan 6% serat (dari berat kering pati) digunakan sebagai penguat biokomposit. Fabrikasi biokomposit menggunakan metode solution casting. Pengujian serapan uap air digunakan untuk mengetahui persentase penyerapan uap air. Gugus fungsi dari biokomposit ditentukan dengan karakterisasi FTIR (Fourier Transform Infra-Red). Persentase penyerapan uap air menunjukkan bahwa, film pati tapioka mempunyai serapan uap 21,7%. Hasil ini lebih tinggi dibandingkan dengan film tapioka ditambah serat. Fenomena ini didukung dengan analisis FTIR pada gugus serapan air sekitar wavenumber 1647 cm-1. Pada daerah tersebut terlihat bahwa, film pati tapioka memiliki absorban yang tinggi dibandingkan film pati tapioka ditambah serat.

Kata-kata kunci: biokomposit, pati tapioka, serat akar buah naga, FTIR, serapan uap air.

Abstract

Tapioca starch biocomposites reinforced dragon fruit root fiber was successfully produced. As much 0, 2, 4 and 6% fiber fractions (from dry starch weight basis) were used as reinforcement in biocomposites. The fabrication of biocomposites was solution casting method. Moisture absorption testing was used to know the percentage of moisture absorption. The functional group of biocomposites was determined by FTIR (Fourier Transform Infra-Red) characterization. The moisture absorption percentage of tapioca starch film was 21,7%. This result was higher than fiber-reinforced biocomposites film. This phenomenon was supported by FTIR analysis on functional group (water absorption band) at wavenumber 1647 cm-1. In this wavenumber, tapioca starch film has higher absorbance than fiber-reinforced biocomposites film.

Keywords: biocomposites, tapioca starch, dragon fruit root fiber, FTIR and moisture absorption.
Autonomous Inflow Control for Maximizing Oil Recovery and Minimizing Water/Steam Production
Authors: Elverhøy Anita B. , Aakre Haavard , Mathiesen Vidar
Published: April 2018

One of the challenges in heavy and extra heavy oil production is to improve the recovery and reduce the water cut. A major part of the world's oil reserves is found in heavy and extra heavy oil reservoirs. One of the problems in heavy oil field with water drive or Steam Assisted Gravity Drainage (SAGD) is the mobility ratio. Due to the high oil viscosity the water and/or steam breakthrough will occur after a short time of production. As the breakthrough expands, the production from the well must be choked or stopped due to high water cut. Inflow Control Device (ICD) and Autonomous Inflow Control Device (AICD) may improve the inflow profile along the well. However, neither ICD nor AICD can shut off the unwanted fluid production completely. The Autonomous Inflow Control Valve (AICV) can shut off the unwanted fluid completely and the technology is presented.

The commercial near-well simulation tool, NETool, is used to model and evaluate different scenarios of completion design. Open hole and AICV completion with zonal isolation are compared. A heterogeneous sand stone reservoir with heavy oil and water or gas breakthrough is modeled. The functionality of the AICV, which is to open for oil and close for low viscous fluids as water, steam and gas is modeled by the predefined RCP function. Experimentally determined flow performance characteristics were used to tune the RCP function, and gave a realistic prediction of the AICV behavior. The simulation results show that the completion with AICVs in combination with packers as zonal isolation, reduces the water cut (WC) and gas oil ratio (GOR) significantly. A study of the impact of number of packers i.e. size of the zones, demonstrates that several small compartments is the most robust solution. The water cut will decrease with increasing number of compartments. The inflow profile is more optimal for the AICV completion than for open hole, and shows the ability to enhance drainage efficiency and oil recovery. The importance of gas/water shut off to maintain or increase the oil production at breakthrough is demonstrated.
Utilizing Intelligent Oilfield Technology and Production Chemicals to Solve Operational Challenges and Increase Production
Authors: Sonne J. , Stepien D. , Coleman M.
Published: April 2018

The Nikaitchuq project on Alaska's remote arctic North Slope incorporates intelligent oilfield technology in the wells and throughout the gathering system and processing facility. Temperature and pressure sensors, level indicators, and flow meters tied into a distributed control system (DCS) are instrumental in completing a comprehensive picture of daily operations and conditions and for allowing operators to make adjustments as events occur. The data from these sensors and meters is historized and streamed from the remote field location to the engineering office 850 miles south. Through the use of this technology, the producer company production team collaborated with a production chemicals provider to identify and trial a chemical solution to solve the operational challenge of bottle-necked production, consequently increasing production. Field data and trends definitively support the efficacy of the product in lowering backpressure on wells, allowing a substantial production gain. Backpressure due to production bottlenecking in the gathering lines inhibited production from wells. With limited resources for manually or operationally removing restrictions, identifying a chemical to decrease the pressure due to friction in the lines was the best prospective option. In many chemical trials, identifying an effective product and quantifying the benefit of the product is difficult. However, use of intelligent oilfield technology enabled each product's effect to be measured and quantified. Prior to the start of the trial, three different production chemicals were prescreened and selected for trial. Each chemical was applied for a set length of time while data was collected and analyzed. Data coming into the DCS in real time enabled the producer company production team to optimize the application rate of each product and determine efficacy and cost efficiency. The wells' bottomhole pressures, the gathering system pressures and temperatures, and the process facility's front-end exchanger differential pressures were all observed to directly assess the efficacy of each product. Furthermore, vessel levels, process temperatures, and sales oil BS&W were monitored to ensure process stability while each new product was introduced to the system. The trial results proved that the backpressure could be relieved chemically. Data collected during the trial allowed the producer company production team to identify one product that outperformed the other two. At optimal rates, Product A relieved 7 psi of backpressure, Product B reduced the back pressure by 35 psi, and Product C reduced the backpressure by 7 psi. Additionally, using the many pressure sensors throughout the gathering system and process, it was possible to identify the restrictive points across which the chemical lowered the differential pressure. Monitoring secondary effects allowed the trial to proceed with minimal negative effects to the overall process.
Opportunities and Challenges of Antelope Shale Development in $50 Oil Price Environment - A Case Study
Authors: Lal M. K. , Singh A. K.
Published: April 2018

The Antelope Shale reservoir, a member of the Monterey Formation in the San Joaquin Valley, offers unique opportunities and challenges. The reservoir comprises three silica phases: Opal A (Diatomite), Opal CT, and Quartz. While the industry has been successful in producing from Opal A (Diatomite) via cyclic steam operations, the resources in the Opal CT and Quartz phases are yet to be commercially established. The recoverable oil estimate from the Monterey was downgraded by the Energy Information Administration (EIA) by 96% from approximately 15 billion barrels to 600 million barrels.

Elk Hills and North Shafter have been successfully producing from the Antelope Shale reservoir. However, the reservoir rock and fluid properties are varied such that extrapolation from one field to the other is difficult. The Opal CT and Quartz commingled completion and stimulation in the McKittrick field showed encouraging initial production response followed by steep decline and operational challenges.

In general, deep drilling and stimulation is expensive in San Joaquin Valley. Industry learning has been slow, less data is available for quality data analytics, which in turn impacts the learning process. In a brown field dominated heavily by thermal recovery processes, unconventional development gets challenged due to higher cost, longer lead times, and relatively poor economics. A typical unconventional resource field takes 4-5 years for achieving optimal development strategy. In a $50 oil price business environment, incremental progress in not enough. We need breakthroughs. It is imperative to optimize the pilot phase and early economic learning for sustainability of the project

In this paper, we discuss the case study of a pilot project wherein four vertical wells were drilled in the McKittrick field. The results showed opportunities for a bigger development plan but were challenged by operational issues, limited analog data set, higher cost, poor economics, and comparison with traditional heavy oil projects. We will also discuss some additional improvement opportunities including imbibition, and drawdown management that have been theoretically established elsewhere and, if applied, could add value to improve the project economics.
Prediction of Toxicity Effects of Oil Field Chemicals Using Adaptive Genetic Neuro-Fuzzy Inference Systems
Authors: Ibrahim H. D. , Odedele T. O.
Published: April 2018

Chemicals are used in various stages of oil production such Drilling (Drilling fluids, cementing, completion and workover fluids), Production, Stimulation and Enhanced Oil Recovery. Many research studies have shown these oil field chemicals have toxic effects on the environment. The oilfield chemicals include various additives for drilling/cementing and work-over such as Fluid loss additives, rheology modifiers, Viscosifiers, Emulsifiers, Biocides, Surfactants, Packer fluid corrosion inhibitors. Toxicity tests are crucial for the assessment of the harmful effects of complex chemical mixtures, such as waste drilling mud, hydraulic fracturing fluid on aquatic environment. The objective of the study is to develop screening protocol to assess, evaluate, and manage the inherent risks. To achieve this, it is imperative to develop models, tools and an acceptable mechanism for screening, predicting and monitoring the application of oil field chemicals. In this paper, Adaptive Genetic Neuro-Fuzzy Inference System is developed to assess the toxicity of oilfield chemicals. Several toxicological studies have shown the evidence of toxicity of some oilfield chemicals to living organisms and their potentially negative side effects on environmental ecosystems for which relatively tedious animal testing methodologies are documented for their assessment. The description of this intelligent system is provided and has proven to have better classification and regression capability and ability to handle high dimensional features. This study adopts a novel evolutionary computing approach to search and obtain the optimal Neuro-Fuzzy parameters to enhance the prediction accuracy and generalization capability of the model. The system was applied to a dataset on Oil Field Chemicals toxicity and it was found that the genetic algorithm yields optimal parameters of Neuro-Fuzzy for the given datasets. The prediction and classification of Oil Field Chemicals (toxic or non-toxic) using this hybrid intelligent system is a work that requires an in-depth study and understanding of the various underlying principles of Neuro-Fuzzy inference system and Genetic Algorithm, which is commonly applied for classification and regression purposes. The developed model based on the fuzzy rules was trained with available data set. The unseen or new data is therefore either classified into appropriate class or have toxicity predicted using gaussian membership function chosen for this application. The motivation of this approach is that it is less cumbersome than the conventional computational modeling usually adopted for chemical classification and characterization. It also seeks to eradicate the existing animal testing that are hitherto very tedious and cumbersome.
How to Plan a SAGD Project, If You Must…
Authors: Farouq Ali S. M. , Byestehparvin Bita
Published: April 2018

Steam-Assisted Gravity Drainage (SAGD) is widely used in Alberta for recovering bitumen from oil (tar) sands. A variation of the same has had some success in heavy oils as well. It is a high-risk recovery method and requires careful planning and design. This paper outlines the success criteria for SAGD, and a design methodology.

First of all, applicability of other lower risk recovery processes, such as steamflood variants, is considered to determine if SAGD is a good choice. SAGD has been successful in oil sands of Alberta under rather restricted conditions. Geology is the most important factor, in particular vertical permeability, oil saturation, and initial mobility of water. Where the minimum criteria are not satisfied, there have been failures, discussed also. The author has developed new equations for the entire SAGD process, not just the stabilized oil flow regime, given previously, and has corrected the errors in the same. These are discussed in detail, with examples. The application of SAGD variations in conventional heavy oils is also considered.

The current experience in Alberta, and elsewhere, is described, and reasons for success/failure are outlined. Given that background, the desirability of SAGD vis-à-vis other thermal processes is discussed for California heavy oils. The variation of SAGD being employed in Saskatchewan heavy oils is also discussed, showing that it is not SAGD in the strict sense, rather a modified steamflood, using horizontal wells. It is concluded that SAGD has a high oil recovery potential if the right combination of rock-fluid properties is present. The application of SAGD to conventional heavy oils is equally problematic, in view of a very different mechanism.

The novelty of the paper lies in (1) a comprehensive treatment of SAGD, from the rising chamber to plateau to decline phases, (2) assessment of SAGD compared to other recovery methods for different types of reservoirs, and (3) application of SAGD variants to conventional heavy oils.
Enhanced Proppant Suspension in a Fracturing Fluid Through Capillary Bridges
Authors: Quintero H. J. , Mattucci M. , O'Neil B. , Folkes G. , Zhang K. , Wang C. Z. , Lu W.
Published: April 2018

The development of tight oil and gas shale relies heavily on multi-staged hydraulic fracturing, with the objective being to induce a complex network of interconnected fractures (artificial and natural), effectively created by water-like viscous fluids and sand laden slurries injected at very high pressures and rates.

Numerous methods have been employed to reduce sand settling and duning during hydraulic fracturing. Conventionally, frac designs have relied on injection rate, and viscoelasticity of the fluid to offset sand, or proppant settling. As of late, development in proppant technologies have focused on introducing alternative engineered materials for proppants that feature oil field brine pseudo specific gravity (S.G.), while maintaining mechanical strength, therefore relying on the buoyancy effect for proppant transport; despite all these efforts, proppant suspension remains a burden for the fracturing fluid.

Herein, we report a pioneering fracturing fluid where through inducing capillary bridges proppant sands become part of the fluid structure and are no longer the burden to be carried. This new fluid system offers a unique and superior proppant transport mechanism, under a wide range of shear stress and rate conditions, without the need for conventional polymers and/or cross-linkers.

This field-proven and cost-effective fracturing fluid features a non-damaging synthetic polymer. Field cases show successful placements of proppant where other conventional fracturing fluids have failed/screened-out.

Regained permeability analysis indicates ≥100% regained permeability when Bandera sandstone (~1 - 10 md permeability) core samples were tested. Proppant settling test analysis showed no proppant settling in a 5 hour period when 500 kg/m3 (4.17 lb/gal) of 30/50 U.S mesh size proppant laden slurry was tested, simulating a bottomhole temperature (BHT) of 70°C (158°F). Also, a more than 33% increase in sand pack volume in the slurry was observed during the aforementioned analysis when compared to a borate-crosslinked guar slurry counterpart.

This paper intends to detail the development, laboratory testing and field cases of this novel fracturing fluid, that has been successfully pumped in more than 150 frac stages in the Western Canadian Sedimentary Basin (WCSB).