bluuebunny/crossref_metadata_2025 huggingface dataset:
A dead giveaway: Foraging vultures and other avian scavengers respond to auditory cues
Authors: Jackson Craig R. , Maddox Thomas , Mbise Franco P. , Stokke Bård G. , Belant Jerrold L. , Bevanger Kjetil , Durant Sarah M. , Fyumagwa Robert , Ranke Peter S. , Røskaft Eivin , May Roel , Fossøy Frode
Published: May 2020

Carrion represents an unpredictable and widely distributed primary food source for vultures and other avian scavengers. Avian scavengers in African savanna ecosystems are reported to rely exclusively on visual stimuli to locate carcasses. However, carnivores’ predation of large mammalian herbivores and subsequent competition for access to the carcass can result in considerable noise, often audible over long distances and for prolonged periods. Vultures and other avian scavengers may therefore detect and respond to these auditory cues, as do the mammalian carnivores alongside which vultures have coevolved, but this has not been investigated to date. Working in the Serengeti ecosystem, Tanzania, we used diurnal auditory broadcasts to simulate predation and competitive carnivore feeding interactions. Based on the current understanding of avian scavenger ecology, we hypothesized that avian responses to call‐in stations would be evoked exclusively by visual, rather than auditory, cues. We therefore predicted that (a) the arrival of avian scavengers at call‐in stations should be preceded and facilitated by mammalian carnivores and that (b) the arrival of avian scavengers would be positively correlated with the number of mammalian scavengers present, which would increase detectability. We recorded 482 birds during 122 separate playback events. In 22% of these instances, avian scavengers arrived first, ruling out responses based exclusively on visual observations of mammalian carnivores, thereby contradicting our first prediction. Furthermore, the first avian arrivals at survey sessions were inversely related to the number of hyenas and jackals present, contradicting our second prediction. Since no bait or carcasses were used during the experiments, these responses are indicative of the birds’ ability to detect and respond to audio stimuli. Our findings challenge the current consensus of sensory perception and foraging in these species and provide evidence that avian scavengers have the ability to use sound to locate food resources.
MitraClip and left ventricular reverse remodelling: a strain imaging study
Authors: Papadopoulos Konstantinos , Ikonomidis Ignatios , Chrissoheris Michael , Chalapas Antonios , Kourkoveli Panagiota , Parissis John , Spargias Konstantinos
Published: May 2020

Aims

The purpose of this study is to identify echocardiography predictors of clinical response and reverse left ventricular (LV) remodelling in patients with functional mitral regurgitation (FMR) treated with MitraClip.

Method and results

We retrospectively analysed 86 high surgical risk patients with severe FMR; of those, 58 were implanted a MitraClip, and 28 received medical treatment and served as controls. At baseline and at 1‐year follow‐up, we performed clinical and echocardiography evaluation to assess global longitudinal strain (GLS) and myocardial work [global work index (GWI), global constructive work (GCW), global wasted work (GWW), global work efficiency (GWE)]. Mitral regurgitation was significantly reduced after MitraClip implantation (3.7 ± 0.4 vs. 1.7 ± 0.8, P < 0.001), and the procedure was associated with improvement in brain natriuretic peptide levels (980 ± 1027 vs. 420 ± 338 pg/mL, P < 0.001), New York Heart Association class status (3.2 ± 0.55 vs. 2.0 ± 0.6, P < 0.001), 6‐min walking test (233 ± 154 vs. 286 ± 114 m, P = 0.01) at follow‐up and reduction of left ventricle end‐systolic (LVESV) and left ventricle end‐diastolic volumes (LVEDV) (152 ± 68 vs. 136 ± 43 mL, P = 0.004 & 219 ± 74 vs. 193 ± 66 mL, P = 0.001, respectively). MitraClip procedure was associated with improvement of LV performance and significant increase of GWI (607 ± 282 vs. 650 ± 260 mmHg%, P = 0.045) and GCW (854 ± 288 vs. 949 ± 325 mmHg%, P < 0.001). Baseline ejection fraction (EF), GLS, GWI, GCW, and effective regurgitant orifice area were the variables that were associated with reduction of LVEDV 1 year after intervention (P < 0.05 for all) and baseline GCW of the LV was the only variable associated with reduction of LVESV (P = 0.002). Receiver operating characteristic curve analysis identified that a GLS cut‐off value of −8.65% (AUC 0.815, P = 0.007) was associated with a 20% reduction of the LVEDV with a sensitivity and specificity of 72% and 70%, respectively, and that a GCW cut‐off value of 846 mmHg% (AUC 0.759, P = 0.007) was associated with a 10% reduction of LVESV with sensitivity and specificity 79% and 74%, respectively.

Conclusions

Mitral valve repair with MitraClip has positive clinical and echocardiographic impact in patients with FMR 1 year after implantation. Preserved GLS and GCW values appear to be associated with LV reverse remodelling post intervention.
Guideline‐directed medical therapy for heart failure does not exist: a non‐judgmental framework for describing the level of adherence to evidence‐based drug treatments for patients with a reduced ejection fraction
Authors: Packer Milton , Metra Marco
Published: May 2020

Numerous guideline documents have issued recommendations to clinicians concerning the treatment of chronic heart failure and a reduced ejection fraction. However, guidelines do not describe what constitutes an acceptable standard of care, and thus, practitioners who adhere to only a small fraction of the recommendations might claim that they are treating patients ‘in accordance with the guidelines’. As a result, <1% of patients with heart failure are receiving all life‐prolonging treatments at trial‐proven doses. A major impediment to the widespread adoption of trial‐based treatments is a lack of any existing framework that would allow physicians to describe the adequacy of care. To address this deficiency, we propose a novel simple approach that would ask practitioners if a patient had been treated using the dosing algorithm that had been shown to be effective for each drug class. The proposed framework recognizes that all landmark survival trials in heart failure were ‘strategy trials’, i.e. the studies mandated a standardized forced‐titration treatment plan that required timely uptitration to specified target dose unless patients experienced clinically meaningful, intolerable or serious adverse events, which persisted or recurred despite adjustment of other medications. Adherence to trial‐proven regimens might be improved if physicians were asked to describe the degree to which a patient's treatment adhered to or deviated from the strategies that had been used to demonstrate the survival benefits of neurohormonal antagonists. The proposed framework should also promote practitioner self‐awareness about the lack of evidence supporting the current widespread use of subtarget doses that are non‐adherent with trial‐proven forced‐titration strategies.
Copper‐Catalyzed One‐Pot Synthesis of 3‐(N‐Heteroarenyl)acrylonitriles through Radical Conjugated Addition of β‐Nitrostyrene to Methylazaarenes
Authors: Moreira Natália M. , Martelli Lorena S. R. , de Julio Kiyara I. R. , Zukerman‐Schpector Julio , Opatz Till , Corrêa Arlene G.
Published: May 2020

A simple procedure for the copper‐catalyzed synthesis of 3‐(N‐heteroaryl)acrylonitriles was developed. Using a combination of Lewis and Brønsted acids, this one‐pot procedure undergoes via a radical conjugated addition and dehydration processes, without isolation of any intermediate, affording the acrylonitriles. This diastereoselective approach allowed the synthesis of a broad scope of quinazoline derivatives (22 examples) with moderate to good yields and good functional‐group tolerance and could be extended to other N‐heterocyles such as quinolines and isoquinolines. Based on control experiments, a mechanistic proposal for this new transformation is also presented.
In situ Growth of a Cobalt‐based Metal‐organic Framework on Multi‐walled Carbon Nanotubes for Simultaneously Detection of Hydroquinone and Catechol.
Authors: Zheng Shengbiao , Hu Jiaqi , Cui Xue , Hu Tao , Zhang Yuyang , Guo Jiahao , Tang Jing , Wang Xuchun
Published: May 2020

In the present study, we report a facile method for preparing a porous MWCNTs/ZIF‐67 nanocomposite with the help of a morphology‐maintained ZIF‐67 in situ growth on multi‐walled carbon nanotubes. Interesting, the MWCNTs/ZIF‐67 nanocomposite demonstrated excellent electrochemical activity for hydroquinone (HQ) and catechol (CC) attribute to the effective interconnections ZIF‐67 crystals and MWCNTs. The analytical curves for HQ and CC obtained by differential pulse voltammetry (DPV) were linear in the range from 0.5 to 100 μM. Benefitting from the excellent conductivity of MWCNTs as well as the high surface area and porosity of ZIF‐67, the advanced nanocomposite displayed good reproducibility, high selectivity and excellent stability, and was successfully employed to assay the content of dihydroxybenzene isomers in the lake water samples.
Development of Miniaturized Electrochemiluminescence Instrument using Multi‐pixel Photon Counter as the Optical Detector
Authors: Dai Wanlin , Zhao Wenyuan , Ma Ying , Ye Jianshan , Jin Jiye
Published: May 2020

We developed a miniaturized electrochemiluminescence (ECL) instrument coupled with a light‐emitting diode‐based bipolar electrochemical sensor (LED‐BPES). This instrument composes of a microcontroller circuit, a power supply circuit, a potentiostat, an optical detecting circuit, and a communication circuit. The multi‐pixel photon counter (MPPC), which is low‐cost, small‐size, and wide‐range in optical measurements, is chosen as the optical detector. The LED‐BPES composes of a disposable screen‐printed carbon electrode (SPCE) and a surface‐mount red LED. Depended on the closed bipolar electrode (C‐BPE) structure, the LED‐BPES not only avoids the employment of unstable and complex ECL reactions but also offers a cost‐effective alternative for the over‐priced ECL reagents by using a mini‐size commercial LED as the luminescent producer. The combination of MPPC and LED‐BPES helps to set up the simplified and downsized instrument system with low price and high efficiency. The presented instrument coupled with LED‐BPES works excellent in electroactive molecules detection and has great potential in the application of heavy metal ions detection.
Performance of Au/Ti and Au/TiO2 Nanotube Array Electrodes for Borohydride Oxidation and Oxygen Reduction Reaction in Alkaline Media
Authors: Jovanović Tiana , Milikić Jadranka , Cvjetićanin Nikola , Stojadinović Stevan , Šljukić Biljana
Published: May 2020

Polarization curves and complex kinetics of oxygen reduction (ORR) and borohydride oxidation (BOR) reaction were evaluated at thin Au layer on Ti and TiO2 electrodes. TiO2 electrodes prepared included amorphous TiO2 (AM−TiO2) and anatase (A−TiO2). The electrodes structure and nanotube arrays morphology were observed by XRD and SEM, respectively. All electrodes show activity for both ORR and BOR. The use of Au layer over A−TiO2 produces the strongest synergistic effect for ORR with exchange of 3 electrons. On the other hand, the strongest effect for BOR was observed in case of Au/Ti.
Effects of reaction parameters on the deoxygenation of soybean oil for the sustainable production of hydrocarbons
Authors: Pimenta João L. C. W. , Barreto Rafael D. T. , dos Santos Onelia A. A. , de Matos Jorge Luiz M.
Published: May 2020

Hydrotreating of vegetable oils offers a green alternative to oil‐derived fuels and raw hydrocarbon materials, usually obtained from oil. In contrast to sulfided catalysts, which contaminate the product with sulfur, carbide‐based catalysts are able to produce clean hydrocarbons. A NiMo carbide‐based catalyst, supported on nanometric γ‐alumina was prepared, characterized by X‐ray crystallography, Nitrogen physisorption, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and Raman spectroscopy. The oxidation temperatures and acidity were also determined. Tests were performed in a batch‐type reactor for the hydrotreatment of soybean oil at 360, 380, and 400°C and 4.5 MPa. Liquid samples were analyzed by gas chromatography with a mass spectra detector. The reaction rate was calculated showing that reactant concentration did not influence deoxygenation rates, nor did the catalyst revealed a significant change in the activity. The product composition was extensively characterized, proving that reaction temperature greatly influences the concentration of aromatic, unsaturated and saturated hydrocarbons, as well as chain size distributions.
Microwave‐assisted catalytic pyrolysis of theEupatorium adenophorumfor obtaining valuable products
Authors: Cheng Song , Zhang Qi , Shu Jianhua , Xia Hongying , Zhang Libo , Peng Jinhui , Lin Guo , Hu Wenhai , Chen Quan
Published: May 2020

Eupatorium adenophorum, global exotic weed, is used as feedstock in the presence of two catalysts to produce renewable biofuels and green chemicals combining with the advantage of microwave heating and catalytic pyrolysis. The effect of catalyst on yield of pyrolysis products is studied. And the pyrolysis product produced from with and without catalytic pyrolysis is analyzed for performance comparisons. The results show that catalytic pyrolysis tends to produce more bio‐oil and less bio‐gas. The bio‐oil from catalytic pyrolysis has more alkane and ketone, and less carboxylic acid compound compared to non‐catalytic pyrolysis, indicates that catalytic pyrolysis could upgrade the quality of bio‐oil. Compared to bio‐gas of non‐catalytic pyrolysis, the catalytic pyrolysis has larger CO and less CO2content, particularly for Sodium chloride (NaCl) catalyst pyrolysis. The bio‐char of NaCl catalytic pyrolysis has higher Brunauer–Emmett–Teller (BET) surface area and total pore volume. The above analysis indicates that catalysts pyrolysis makes the properties of pyrolysis product tend to good tendency.
Experimental evaluation of the efficiency performance of the DMFC
Authors: Bayramoğlu Mahmut , Ciğeroğlu Zeynep , Kazan Emine Sena
Published: May 2020

This study represents the experimental assessment of the faradaic, fuel, and energetic efficiency of active direct methanol fuel cell (DMFC). The experimental system was equipped with several sensors, HPLC and UV spectroscopy to make on‐line and off‐line measurements of different components. A polarization study was conducted and an experimental plan was applied to collect the process data during 3‐hour runs. Finally, stoichiometric and various efficiency calculations were performed based on the system and the process data. The results showed that the cell performance was better at higher operating temperatures (70.8 mW cm−2 @75°C). Faradaic efficiency and fuel efficiency were better at low temperatures and estimated as 55.8% and 59.6% at 55°C, respectively. Energetic efficiency was better at higher temperatures due to the faster anode kinetics and was found as 12.3% at 75°C. The efficiencies were strongly dependent on methanol concentration. Methanol crossover was increased with increasing methanol concentration; hence the efficiencies were decreased.
Structure‐from‐motion photogrammetry analysis of historical aerial photography: Determining beach volumetric change over decadal scales
Authors: Carvalho Rafael C. , Kennedy David M. , Niyazi Yakufu , Leach Chloe , Konlechner Teresa M. , Ierodiaconou Daniel
Published: May 2020

Historical aerial photographs are an invaluable tool in shoreline mapping and change detection in coastal landscapes. We evaluate the extent to which structure‐from‐motion (SfM) photogrammetric methods can be applied to quantify volumetric changes along sandy beaches, using archival imagery. We demonstrate the application of SfM‐derived digital surface models (DSMs) at East Beach and Lady Bay in southwest Victoria, Australia, using photographic datasets taken in 1969, 1977 and 1986, and compare them to LiDAR‐derived DSMs acquired at both sites in 2007. The SfM approaches resulted in two entire and two partial suitable DSMs out of six datasets. Good‐quality DSMs were spatially continuous with a good spread of ground control points (GCPs) near the beach at Lady Bay, whereas unsuitable DSMs were mostly restricted by poor distribution and number of GCPs in spatially segmented areas of East Beach, due to limited overlapping of images, possible poor quality of GCPs and also the propagation of errors in the derived point clouds. A volume of approximately 223 000 ± 72 000 m3 was deposited at Lady Bay between 1969 and 2007, despite minimal erosion observed near the breakwater. The partially suitable dataset of East Beach indicated that beach erosion of at least 39 m3 m−1 occurred immediately to the east of the seawall after 1977. We also discuss the drawbacks and strengths of SfM approaches as a benchmark of historical erosion assessments along sandy beaches. © 2020 John Wiley & Sons, Ltd.
An integral equation method for closely interacting surfactant‐covered droplets in wall‐confined Stokes flow
Authors: Pålsson Sara , Tornberg Anna‐Karin
Published: May 2020

A highly accurate method for simulating surfactant‐covered droplets in two‐dimensional Stokes flow with solid boundaries is presented. The method handles both periodic channel flows of arbitrary shape and stationary solid constrictions. A boundary integral method together with a special quadrature scheme is applied to solve the Stokes equations to high accuracy, also for closely interacting droplets. The problem is considered in a periodic setting and Ewald decompositions for the Stokeslet and stresslet are derived. Computations are accelerated using the spectral Ewald method. The time evolution is handled with a fourth‐order, adaptive, implicit‐explicit time‐stepping scheme. The numerical method is tested through several convergence studies and other challenging examples and is shown to handle drops in close proximity both to other drops and solid objects to high accuracy.
High dietary oleic acid in olive oil‐supplemented diet enhanced omega‐3 fatty acid in blood plasma of rats
Authors: Nogoy Kim Margarette C. , Kim Hyoun Ju , Lee Yehyun , Zhang Yan , Yu Jia , Lee Dong Hoon , Li Xiang Zi , Smith Stephen B. , Seong Hyun A , Choi Seong Ho
Published: May 2020

This study was conducted to investigate the effect of dietary oleic acid in olive oil‐supplemented diets on the blood lipid profile and fatty acid composition in blood plasma and adipose tissue of rats. A total of 60 Sprague Dawley rats with mean body weight of 249 g ± 3.04 g were equally divided into three diet groups: control (CON) contained 10% coconut oil, olive50 contained 5% coconut oil and 5% olive oil, and olive100 contained 10% olive oil. Oleic acid (OA) level was highest in olive100 followed by the olive50 and control. The final body weight (BW) of the rats was significantly affected by the intake of OA, in which rats fed olive100 had the lowest final BW, which signified that OA could be associated with weight loss. Olive oil intake significantly increased levels of the high‐density lipoprotein cholesterol (HDL‐C) and exhibited a potential attenuation effect on the glutamic‐oxaloacetic transaminase and the glutamic‐pyruvic transaminase, and a potential role in the reduction of triglycerides in the bloodstream of the animals. In terms of fatty acid composition, significantly high OA was observed in the blood plasma and adipose tissues of rats fed olive100. Omega‐3 polyunsaturated fatty acids (PUFAs), such as linolenic (C18:3 n−3), eicosapentaenoic (C20:5 n−3), and docosahexaenoic (C22:6 n−3), and n−6 PUFA arachidonic (C20:4 n−6) were also significantly increased in the blood plasma of rats fed olive100. These findings suggest that the intake of dietary high OA may enhance the omega‐3 fatty acid levels in the blood plasma of rats and may have a positive effect in reducing risks to cardiovascular disease, as evidenced by weight loss, increased HDL‐C levels, and decreased TG levels in the blood plasma of experimental animals.
An Experimental Investigation of the Effects of Operating Conditions on Anisotropic Electrical Conductivity in a PEM Fuel Cell
Authors: Taş M. , Elden G.
Published: May 2020

This study aimed to investigate the effects of the operating conditions on the anisotropic electrical conductivity of diffusion layers in a polymer electrolyte membrane fuel cell. For this purpose, two different gas diffusion layers were considered. The electrical conductivity values of the selected gas diffusion layers in both in‐plane and through‐plane directions were examined experimentally, depending on cell temperature, relative humidity and clamping pressure. Resistance measurements were carried out for all combinations of operating conditions where cell temperature, relative humidity (RH) and clamping pressure were changed from 50 °C to 80 °C, from 70% to 100% and from 2 bars to 8 bars, respectively. The results showed that although the relative humidity had a dominant effect on the in‐plane conductivities for both the gas diffusion layers, it did not significantly affect the through‐plane conductivities. The through‐plane conductivities increased with the increase of the cell temperature and the clamping pressure, whereas the in‐plane conductivities did not remarkable change.
Analysis and assessment of a nanoparticle seeded small scale absorption refrigeration system driven by a low‐grade waste heat source
Authors: Modi Bhaumik , Ginoya Ankit , Mudgal Anurag , Patel Vivek
Published: May 2020

The thermoeconomic behaviour of a nanoparticle seeded single effect LiBr‐H2O absorption refrigeration system (ARS) is investigated for a small scale application. In the proposed method, alumina nanoparticles with volume concentrations of 3%, 5%, and 7% are dispersed into an aqua lithium bromide solution. The multiobjective heat transfer search algorithm is employed to examine the design trade‐off between the coefficient of performance (COP) and total annualized cost (TAC). To analyze the overall performance of the system, the influence of five design parameters, namely the temperatures of the generator, absorber, evaporator, condenser and heat exchanger pipe diameter, are studied. It is found that with an increase in the COP, the TAC of the system is initially raised marginally, and after that, raised rigorously with further increment. The comparative results indicate that the COP and TAC of the nanofluid based ARS system are increased by about 7% and decreased by about 3.2%, respectively, corresponding to the Pareto points of the base ARS system. A lower break‐even point of about 2.6 years is achieved for the ARS system containing nanoparticles compared to the base ARS system. Overall, the ARS system containing 5% nanoparticles is the best solution from a thermodynamic and economic point of view.
Identity‐based motivation: Connections between first‐year students' engineering role identities and future‐time perspectives
Authors: Godwin Allison , Kirn Adam
Published: May 2020

Background

Research in engineering education has highlighted the importance of identity and motivation for a number of student outcomes, including persistence. However, these constructs have often been studied separately, despite theorized and demonstrated connections between students' identity and motivation in other fields.

Purpose/Hypothesis

Our study fills this gap by investigating the connections between identity and motivation. We specifically examined the connections between students' engineering role identity and future‐time perspective (FTP; a theory of human motivation) theories to understand students' interest in choosing an engineering major after their first year, which we call continuing engineering major interest.

Design/Methods

The data came from a questionnaire distributed during Fall 2015 (n = 2,879). Structural equation modeling was used to understand the connections between the latent factors of engineering role identity and FTP. We also examined the predictive validity of this model on students' continuing engineering major interest.

Results

Our results show connections between students' engineering role identity and the domain‐specific constructs of FTP. Identity was fully mediated by students' FTPs, and these perspectives were important for predicting continuing major interest. Engineering role identity measures explained a combined 69% of the variance in the FTP measures, and engineering role identity and FTP measures together explained 14.2% of the variance in engineering major interest.

Conclusions

These findings provide empirical evidence for linking identity and motivation in studies of engineering students' career pathways. The results of this work inform how theories of identity and motivation can be used collectively in engineering education research.
Factors driving nutrient trends in streams of the Chesapeake Bay watershed
Authors: Ator Scott W. , Blomquist Joel D. , Webber James S. , Chanat Jeffrey G.
Published: May 2020

Despite decades of effort toward reducing nitrogen and phosphorus flux to Chesapeake Bay, water‐quality and ecological responses in surface waters have been mixed. Recent research, however, provides useful insight into multiple factors complicating the understanding of nutrient trends in bay tributaries, which we review in this paper, as we approach a 2025 total maximum daily load (TMDL) management deadline. Improvements in water quality in many streams are attributable to management actions that reduced point sources and atmospheric nitrogen deposition and to changes in climate. Nutrient reductions expected from management actions, however, have not been fully realized in watershed streams. Nitrogen from urban nonpoint sources has declined, although water‐quality responses to urbanization in individual streams vary depending on predevelopment land use. Evolving agriculture, the largest watershed source of nutrients, has likely contributed to local nutrient trends but has not affected substantial changes in flux to the bay. Changing average nitrogen yields from farmland underlain by carbonate rocks, however, may suggest future trends in other areas under similar management, climatic, or other influences, although drivers of these changes remain unclear. Regardless of upstream trends, phosphorus flux to the bay from its largest tributary has increased due to sediment infill in the Conowingo Reservoir. In general, recent research emphasizes the utility of input reductions over attempts to manage nutrient fate and transport at limiting nutrients in surface waters. Ongoing research opportunities include evaluating effects of climate change and conservation practices over time and space and developing tools to disentangle and evaluate multiple influences on regional water quality.
Development and validation of stability indicating chromatographic methods for simultaneous determination of citicoline and piracetam
Authors: Abdelrahman Maha M. , Ahmed Amal B. , Omar Mahmoud A. , Derayea Sayed M. , Abdelwahab Nada S.
Published: May 2020

Citicoline and piracetam were subjected separately to different stress conditions as recommended by the international conference on harmonization. In addition, new stability indicating thin layer chromatographic and ultra high performance liquid chromatographic methods have been developed and validated for simultaneous determination of citicoline and piracetam in presence of their degradation products. Separation on the proposed thin layer chromatographic method was carried out using a developing system containing methanol:chloroform:ammonium chloride buffer (9:1:2, v/v/v) on silica gel plates at 230 nm. On the other hand, the mobile phase in the ultra high performance liquid chromatographic method was composed of water (containing 0.1% triethylamine):ethanol (92:8, v/v). The flow rate was 1 mL/min and ultraviolet detection was at 230 nm. Moreover, results of the developed methods were statistically compared to those obtained by the reported high‐performance liquid chromatography method and no significant difference between them was found. The greenness profile of ultra high performance liquid chromatographic method was assessed and compared with those of the previously published high‐performance liquid chromatography methods, it was noticed that the proposed ultra high performance liquid chromatographic method more environmentally friendly and greener than other methods.
Distributed Feedback Lasers Based on Green Fluorescent Protein and Conformal High Refractive Index Oxide Layers
Authors: Karl Markus , Meek Andrew , Murawski Caroline , Tropf Laura , Keum Changmin , Schubert Marcel , Samuel Ifor D. W. , Turnbull Graham A. , Gather Malte C.
Published: May 2020

Fluorescent proteins have emerged as an attractive gain material for lasers, especially for devices requiring biocompatibility. However, due to their optical properties, integration with distributed feedback (DFB) resonators is not readily achievable. Here, a DFB laser with enhanced green fluorescent protein (eGFP) as the gain material is demonstrated by incorporating a thin (65 nm), high refractive index (n = 2.12) ZrO2 interlayer as waveguide core. Deposition of ZrO2 via atomic layer deposition yields a smooth and conformal film as required to minimize optical losses. Lasing emission is obtained from 2D second‐order DFB eGFP lasers at pump power densities above 56.6 kW cm–2 and a wavelength tuning range of Δλ = 51.7 nm is demonstrated. Furthermore, it is shown that in contrast to conventional organic DFB lasers, both transverse electric (TE) and transverse magnetic (TM) modes are accessible. The effective refractive index of these modes can be predicted accurately through optical modelling. Using far‐field imaging, the laser beam profile is studied and TE and TM modes are distinguished.
3D Mesh Releasing Method: A Retrospective Analysis of Fractional CO2 Treatment on Contracture Scars
Authors: Xi Wenjing , Xie Yixin , Zhang Zheng , Li Ke , Wang Jingyan , Li Jie , Feng Shaoqing , Hultman C. Scott , Liu Ying , Zhang Yixin
Published: May 2020

Background and Objectives

There has been reports on fractional CO2 laser successfully improving contracture scars that impair the function of a joint. It seems that certain contracture problems could be solved by laser instead of surgery. However, the clinical application could be difficult when the efficacy of the method remains unknown. The purpose of this study is to report the releasing capacity of the fractional CO2 laser on contracture scars based on a defined treatment method.

Study Design/Materials and Methods

We conducted a retrospective study in patients with limited function in joints caused by contracture scars. Fractional CO2 laser and our “3D mesh releasing” protocol were applied. The primary outcome was the improvement measured in range of motion (ROM) of the relevant joint before all intervention and 6 months after the last treatment.

Result

From November 2016 to January 2018, 11 joints of 10 cases were treated by the fractional CO2 laser. Patients went through 2.27 (standard deviation [SD] 1.42, 1‐5) sessions. The average progress of ROM before and 6 months after all treatments was 19.13° (SD 10.25, P < 0.02). In six cases, we recorded that there was an 8.53° (SD 5.81, P < 0.02) of increase in ROM immediately after the laser session, and the average improvement reached up to 13.58° (SD 8.15, P < 0.02) after 2–3 months during the next follow‐up.

Conclusion

The fractional CO2 laser could achieve functional improvement in contracture scars and it maintained its effect for at least 6 months. The “3D Mesh Releasing” protocol would help to standardize the treatment procedure. This modality has minimal‐invasiveness and potentially could become a supplement to the current treatment choices for mild contracture scars. Lasers Surg. Med. © 2020 Wiley Periodicals LLC
Improvement in Mechanical and Thermal Properties of Transparent Semi‐Aromatic Polyimide by Crosslinking
Authors: Chen Zhigeng , Zhang Sen , Feng Qi , Wu Yancheng , Liu Shumei , Zhao Jianqing
Published: May 2020

Both the formation of insoluble salt for aliphatic diamines and the poor reactivity for aliphatic dianhydrides result in semi‐aromatic polyimide (SAPI) with low molecular weight and, thereby, in highly brittle SAPI films in nature. To solve the above problems, a cyclic‐olefin copolymer synthesized from norbornene and maleic anhydride is used as the third monomer (crosslinking agent) to prepare the crosslinked SAPI (cSAPI) films. The relative viscosity of the precursor solution of cSAPI is increased with the loading of cyclic‐olefin copolymer, giving rise to the improvement in mechanical and thermal properties of cSAPI films. The tensile modulus, tensile strength, and elongation at break of cSAPI film with 5 wt% cyclic‐olefin copolymer are increased to 4.49 GPa, 137 MPa, and 14.9% from 3.57 GPa, 111 MPa, and 7.6%, respectively, compared to those of the baseline SAPI film. Meanwhile, the glass transition temperature of cSAPI films is increased to 282 from 270 °C of the SAPI film, which is advantageous to better meet the requirement for high‐temperature manufacturing processes such as lead‐free solder reflowing. In addition, all cSAPI films exhibit good optical transparency in the entire visible region.
Selectivity of Thermal Analysis in the Branching Analysis of Low Density Polyethylene
Authors: Eselem Bungu PaulSeverin , Pflug Kristina , Pasch Harald
Published: May 2020

Low density polyethylene (LDPE) exhibits a complex branching architecture that is characterized by the numbers and lengths of the branches. In previous work, it has been demonstrated that comprehensive microstructural information on LDPE can only be obtained via multiple preparative fractionations and subsequent advanced analysis of the fractions. In this work, microstructural differences of LDPE with similar molar masses but different melt flow indexes are addressed. The samples are fractionated using the multiple preparative fractionation concept to generate narrowly distributed branch and molar mass fractions, respectively. The individual fractions are cross‐fractionated by stepwise recrystallization using successive self‐nucleation and annealing to obtain endotherms with multiple peaks (seeds). Each seed represents a population of chains with similar branching structure or crystallizable methylene sequences. The methylene sequence lengths (MSLs) and the seed contents of the seeds with the highest population are compared for fractions with similar fractionation characteristics. Fractions showing significant differences in their MSL and/or seed content are investigated further using advanced analytical techniques and 2D liquid chromatography (2D‐LC), to correlate MSL or seed content to the branching structure.
Conformation and Diffusivity of Ring and Linear Polyethylene Oxide in Aqueous Solution: Molecular Topology Dependent Concentration Effects and Comparison with Experimental Data
Authors: Tsalikis Dimitrios G. , Alexiou Terpsichori S. , Alatas Panagiotis V. , Mavrantzas Vlasis G.
Published: May 2020

Atomistic molecular dynamics simulations are performed on aqueous solutions of ring and linear polyethylene oxide (PEO) under good solvent conditions for the investigation of their conformation and diffusion dynamics. The systems simulated span a wide range of molecular weights (from 2 to 10 k) and polymer concentrations. In the limit of infinite dilution, both conformational and dynamic properties appear to be practically molecular topology independent as far as their dependence on chain length and concentration is concerned, and a very favorable agreement is observed with respect to relevant well‐established theoretical predictions, experimental data, and earlier simulation studies. Crossing over to the semidilute regime, molecular topology starts to bear a distinct effect on the observed conformations of the two different molecular geometries. On the other hand, the diffusion dynamics of PEO in the semidilute regime appears to be practically molecular topology independent judging from the dependence of the chain center‐of‐mass diffusivity on chain length and concentration. Indeed, and despite the fact that ring molecules exhibit consistently a faster dynamics than their linear homologs over the entire concentration range simulated, the estimated concentration scalings for both types of architecture are strikingly similar. The findings of this work are compared with scaling arguments and available experimental data.
Concentration and effective T2 relaxation times of macromolecules at 3T
Authors: Landheer Karl , Gajdošík Martin , Treacy Michael , Juchem Christoph
Published: May 2020

Purpose

We aimed to investigate the concentration and effective T2 relaxation time of macromolecules assessed with an ultra‐short TE sLASER sequence in 2 brain regions, the occipital and frontal cortex, in both genders at 3T.

Methods

An optimized sLASER sequence was used in conjunction with a double‐inversion preparation module to null the metabolites. Eight equally spaced TEs were chosen from 20.1 to 62.1 ms, and the macromolecules were modeled by 10 line broadened singlets. The amplitude of each of the macromolecule signals was extracted at each TE and fit to a monoexponential function to extract the respective effective T2 values. Absolute quantification of the macromolecule resonances was performed using water signal as a reference. A total of 10 young healthy adult subjects (5 females) were scanned, with spectra being obtained from both the frontal and occipital cortex. Differences in the effective T2 relaxation times and concentrations were investigated between both regions and genders.

Results

A wide disparity was observed between the effective T2 values of the individual resonances; however, no significant differences between gender or region for any of the measured macromolecule concentration or effective T2 values were found.

Conclusion

The effective T2 relaxation times and concentration of 10 different macromolecule resonances were measured and found to be well represented by the monoexponential model. These results will be useful for absolute quantification of macromolecules in future studies, or in the generation of synthetic basis sets for optimization or machine learning.
Effects of a Gonadotropin-Releasing Hormone IIa 5/20-μg/kg Dose versus a 20/80-μg/kg Dose on Channel Catfish Ovulation
Authors: Quiniou Sylvie M A , Bosworth Brian G
Published: May 2020

The production of (male Blue Catfish Ictalurus furcatus × female Channel Catfish Ictalurus punctatus) F1 hybrids by U.S. catfish farmers has increased dramatically during the last 15 years. However, hybrid catfish production requires hormone-induced ovulation of female Channel Catfish and remains an inefficient process. Previously, we demonstrated that GnRH IIa given as a two-dose injection (priming/induction) of 20/80 μg/kg of female body weight resulted in superior ovulation rates for Channel Catfish compared with salmon GnRH IIIa and mammalian LHRHa, which are products that are currently used at commercial catfish hatcheries. The objective of the current study was to determine whether GnRH IIa given at a quarter dose (5/20 μg/kg) would achieve results similar to those that were obtained with the full dose (20/80 μg/kg) and whether the response varied over the spawning season. Trials were conducted at three timepoints during the 2017 spawning season: early (May 1), middle (May 15), or late (June 5). At each timepoint, 20 females received an intraperitoneal injection with a full dose of GnRH IIa and 20 females received an injection with a quarter dose of GnRH IIa. Data were collected for female weight, latency, incidence of ovulation, and stripped eggs weight (g) per kilogram of female body weight. The data indicated that the quarter dose of GnRH IIa (5/20 μg/kg of female body weight) achieved results that were similar to those that were obtained with the full dose of 20/80 μg/kg.
Goal‐oriented model reduction of parametrized nonlinear partial differential equations: Application to aerodynamics
Authors: Yano Masayuki
Published: May 2020

We introduce a goal‐oriented model reduction framework for rapid and reliable solution of parametrized nonlinear partial differential equations with applications in aerodynamics. Our goal is to provide quantitative and automatic control of various sources of errors in model reduction. Our framework builds on the following ingredients: a discontinuous Galerkin finite element (FE) method, which provides stability for convection‐dominated problems; reduced basis (RB) spaces, which provide rapidly convergent approximations; the dual‐weighted residual method, which provides effective output error estimates for both the FE and RB approximations; output‐based adaptive RB snapshots; and the empirical quadrature procedure (EQP), which hyperreduces the primal residual, adjoint residual, and output forms to enable online‐efficient evaluations while providing quantitative control of hyperreduction errors. The framework constructs a reduced model which provides, for parameter values in the training set, output predictions that meet the user‐prescribed tolerance by controlling the FE, RB, and EQP errors; in addition, the reduced model equips, for any parameter value, the output prediction with an effective, online‐efficient error estimate. We demonstrate the framework for parametrized aerodynamics problems modeled by the Reynolds‐averaged Navier‐Stokes equations; reduced models provide over two orders of magnitude online computational reduction and sharp error estimates for three‐dimensional flows.
Molar Entropy and Enthalpy of CO Adsorbed in Zeolites as Derived from VTIR Data: Role of Intermolecular Modes
Authors: Garrone Edoardo , Otero Areán Carlos , Rodríguez Delgado Montserrat , Bonelli Barbara
Published: May 2020

Detailed analysis of recently reported variable‐temperature IR (VTIR) spectra of carbon monoxide adsorbed in alkaline zeolites shows how, not only the corresponding values of standard adsorption enthalpy (
) and entropy (
) can be obtained, but also the thermodynamic values of molar entropy and enthalpy which characterize the adsorbed gas phase. In addition, it is shown that the so obtained molar entropy data can lead to new insights into soft molecular modes, which would be hardly accessible by conventional IR spectroscopic techniques.
Enhancing the promiscuity of a member of the Caspase protease family by rational design
Authors: Öhlknecht Christoph , Petrov Drazen , Engele Petra , Kröß Christina , Sprenger Bernhard , Fischer Andreas , Lingg Nico , Schneider Rainer , Oostenbrink Chris
Published: May 2020

The N‐terminal cleavage of fusion tags to restore the native N‐terminus of recombinant proteins is a challenging task and up to today, protocols need to be optimized for different proteins individually. Within this work, we present a novel protease that was designed in‐silico to yield enhanced promiscuity toward different N‐terminal amino acids. Two mutations in the active‐site amino acids of human Caspase‐2 were determined to increase the recognition of branched amino‐acids, which show only poor binding capabilities in the unmutated protease. These mutations were determined by sequential and structural comparisons of Caspase‐2 and Caspase‐3 and their effect was additionally predicted using free‐energy calculations. The two mutants proposed in the in‐silico studies were expressed and in‐vitro experiments confirmed the simulation results. Both mutants showed not only enhanced activities toward branched amino acids, but also smaller, unbranched amino acids. We believe that the created mutants constitute an important step toward generalized procedures to restore original N‐termini of recombinant fusion proteins.
Field detection and predicted evolution of spinosad resistance in Ceratitis capitata
Authors: Guillem‐Amat Ana , Sánchez Lucas , López‐Errasquín Elena , Ureña Enric , Hernández‐Crespo Pedro , Ortego Félix
Published: May 2020

BACKGROUND

The sustainable control of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), is compromised by the development of resistance to malathion and lambda‐cyhalothrin in Spanish field populations. At present, field populations remain susceptible to spinosad. However, the resistant strain JW‐100s has been obtained under laboratory selection with spinosad, and resistance has been associated with the presence of different mutations causing truncated transcripts of the α6 subunit of the nicotinic acetylcholine receptor (nAChRα6).

RESULTS

An F1 screen assay followed by the molecular characterization of surviving flies has been used to search for spinosad‐resistant alleles in field populations. Two different resistant alleles giving rise to truncated isoforms of Ccα6 have been identified, which corresponds to an estimated allelic frequency of at least 0.0023–0.0046. The fitness values of the resistant nAChRα6 alleles found in the laboratory strain JW‐100s were estimated to be 0.4 for RR and 0.2 for SR. Mathematical modelling predicted that spinosad‐resistant alleles will rapidly decline over time in field populations if their fitness cost was the same as estimated for laboratory‐resistant alleles. However, they are predicted to increase in the field if their fitness cost is lower and resistance management strategies are not implemented.

CONCLUSION

Spinosad‐resistant alleles have been detected in field populations for the first time. Our modelling simulations indicate that the best option to delay the appearance of spinosad resistance would be its rotation with other insecticides without cross‐resistance. The integrated F1 screen/molecular genetic analysis presented here can be used for future monitoring studies. © 2020 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Predation interactions among henhouse‐dwelling arthropods, with a focus on the poultry red mite Dermanyssus gallinae
Authors: Zriki Ghais , Blatrix Rumsaïs , Roy Lise
Published: May 2020

BACKGROUND

Analysis of the poorly explored food webs of henhouse‐dwelling arthropods would improve biological control against the poultry red mite (PRM) Dermanyssus gallinae (De Geer). This study aimed to identify trophic links among native predatory arthropods, PRM, and alternative preys. In vitro predation tests were carried out to assess (i) the ability of native predators to feed on PRM juvenile and adult stages in two physiological statuses (unfed and freshly blood‐fed) in the absence of any physical barrier, (ii) predator preferences between PRM and astigmatic mites, and (iii) predation interactions between PRM predators.

RESULTS

Ten arthropod taxa fed on PRM with predation rates ranging from 4% to 95% in our experimental conditions. They belonged to (i) Acari: Androlaelaps casalis (Berlese), Cheyletus spp., Macrocheles muscaedomesticae (Scopoli), M. penicilliger (Berlese), Parasitus fimetorum (Berlese), Dendrolaelaps spp. and Uroobovella fimicola (Berlese); (ii) other Arachnida: Lamprochernes nodosus (Schrank) (Pseudoscorpionida) and a linyphiid spider; and (iii) Insecta: Lyctocoris campestris (Fabricius). These predators varied in their preference for PRM stages and physiological statuses (unfed or freshly blood‐fed). When given a choice, most predators preferred to feed on PRM than astigmatic mites. Bidirectional predation occurred within two pairs of PRM predators (M. penicilliger–Lamprochernes nodosus and A. casalis–Cheyletus spp.), and M. penicilliger had a 100% predation rate on A. casalis.

CONCLUSION

Our study highlights the potential of various arthropod predators occurring naturally in poultry houses for conservation and augmentative biological control of PRM. Predation interactions between these predators should be accounted for before developing biocontrol agents against PRM. © 2020 Society of Chemical Industry