bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of mitomycin analogs catalyzed by coupling of laccase with lipase and the kinetic model
Authors: Zhang Yuanyuan , Sun Yangjian , Ren Wenjie , Zhao Qiuxiang , Lv Kuiying , Tang Hui , Gao Xin , Yang Fengke , Wang Fanye , Liu Junhong
Published: January 2020

BACKGROUND

Mitomycin C (MMC) is one of the most important members of the mitomycin family that have been widely used as a strong antineoplastic antibiotic for treating various tumors. In this study, enzymatic oxidation/amination reaction of 2‐methyl‐1,4‐hydroquinone with n‐butylamine was carried out to synthesize 2‐methyl‐3‐n‐butylaminoyl‐1,4‐benzoquinone mitomycin analogs.

RESULTS

A kinetic model was developed based on an ordered sequential mechanism for this cascade reaction system catalyzed by two enzymes, which revealed that the limiting step of the system was the laccase‐mediated oxidation of 2‐methyl‐3‐n‐butylaminoyl‐4‐hydro‐1‐quinone and removing the limiting step resulted in a yield increase from 88.3% to 96.7%.

CONCLUSION

The developed kinetic model fitted the test data very well, indicating that the reactions catalyzed by coupling of laccase with lipase might follow the ordered sequential mechanism with product inhibition. Synthesis of mitomycin analogs catalyzed by coupling of laccase with lipase has great potential for practical application. © 2020 Society of Chemical Industry
Rapid detection of foodborne bacterial pathogens using visual high‐throughput microfluidic chip
Authors: Jin Zengjun , Ding Guotao , Li Guiying , Yang Guoxing , Han Yonghong , Hao Ning , Deng Jian , Zhang Yan , Zhang Wei , Li Weihao
Published: January 2020

BACKGROUND

Foodborne diseases are a major global public health concern. It is urgent to monitor foodborne pathogens from contaminated foods based on multi‐target detection.

RESULTS

In this work, a self‐priming compartmentalization (SPC) microdevice made of poly(methyl methacrylate) (PMMA) was developed and integrated into a loop‐mediated isothermal amplification (LAMP) system for performing high‐throughput visual detection. The microfluidic chip is a self‐filling microwell array which can introduce reaction solution only through an access hole in a vacuum pumping system. The independent and closed wells can avoid cross‐contamination and ensure the accuracy of the results. The approach was able to perform the simultaneous identification of six foodborne pathogens (Salmonella typhimurium, Bacillus cereus, Staphylococcus aureus, Yersinia enterocolitica, Vibrio parahaemolyticus and Listeria monocytogenes) within 1 h. The results demonstrated that the method could specifically recognize the six foodborne pathogens.

CONCLUSION

The use of a LAMP‐based microdevice can be a faster alternative to conventional methods to detect pathogens in food samples, especially for those foods in which no pathogen is allowed (S. aureus), or foods for infant use. The simplicity and portability of the device can provide an alternative platform for foodborne pathogens where food safety needs accurate and timely detection confirmation. © 2020 Society of Chemical Industry
Microscopic and spectroscopic characterization of rice and corn starch
Authors: Govindaraju Indira , Pallen Sparsha , Umashankar Suchitta , Mal Sib Sankar , Kaniyala Melanthota Sindhoora , Mahato Dhani Ram , Zhuo Guan‐Yu , Mahato Krishna Kishore , Mazumder Nirmal
Published: January 2020

Starch granules from rice and corn were isolated, and their molecular mechanism on interaction with α‐amylase was characterized through biochemical test, microscopic imaging, and spectroscopic measurements. The micro‐scale structure of starch granules were observed under an optical microscope and their average size was in the range 1–100 μm. The surface topological structures of starch with micro‐holes due to the effect of α‐ amylase were also visualized under scanning electron microscope. The crystallinity was confirmed by X‐ray diffraction patterns as well as second‐harmonic generation microscopy. The change in chemical bonds before and after hydrolysis of the starch granules by α‐ amylase was determined by Fourier transform infrared spectroscopy. Combination of microscopy and spectroscopy techniques relates structural and chemical features that explain starch enzymatic hydrolysis which will provide a valid basis for future studies in food science and insights into the energy transformation dynamics.
Bond strength and adaptation of pulp capping materials to dentin
Authors: Karadas Muhammet , Atıcı Makbule Gamze
Published: January 2020

This study evaluated the shear bond strength (SBS) and internal marginal adaptation of pulp‐capping materials to dentin. Flat occlusal deep dentin surfaces were produced and randomly assigned to two groups (sound or artificial caries‐affected dentin). The specimens in each group were assigned to one of seven subgroups according to the materials used: Biodentine, Theracal LC, Ultra‐Blend plus, Calcimol LC, ApaCal ART, EQUIA Forte, and Ionoseal. Buildups (3‐mm inner diameter and 2‐mm deep) were made over the dentin surfaces. The bonded specimens were tested under shear forces at a crosshead speed of 0.8 mm/min and fracture modes were determined using a stereomicroscope at 25× magnification. The materials were applied to the pulp floor of prepared Class I cavities and then the cavities were restored with composite resin. Restored molar teeth were subjected to 5,000 thermocycles and sectioned in a bucco–lingual direction. Resin replicas were made to determine the adaptation at the pulp floor with scanning electron microscopy. Significant differences were determined among both bond strengths and gap formations of the materials. EQUIA Forte applied to both dentin substrates had a significantly higher SBS than the other materials. The bond strength of each material was not influenced by the dentin condition. Biodentine (3.03%), EQUIA Forte (7.83%), and Theracal LC (13.37%) had lower gap formations compared to other materials but were not significantly different from each other.
Direct care nurses and support staff thoughts and feelings about the reasons patients fall at a cancer center
Authors: McDonald Kathie , Vonnes Cassandra , Hartranft Susan
Published: January 2020

Extensive research addresses the prevalence and high fall risk for cancer patients related to age, diagnosis, treatment side effects, pharmacological side effects, and cognitive and/or motor deficits. The purpose of the study was to explore the thoughts and feelings that inpatient and outpatient oncology direct care nurses (registered nurses) and support staffs have about reasons patients fall; as well as their thoughts on what might be done to prevent falls. This descriptive qualitative study used focus groups as the method for discovery. Six themes were identified: Effect on Me, Guilt, Noncompliance, Poor Choices, Inconsistency, and No Authority.

This study is significant and relevant because there is little previous research addressing staff thoughts and feelings about why patients fall and what additional interventions they think can be implemented to prevent falls. Findings from this study may be helpful in developing and/or refining current fall policies. Existing research suggests unlicensed patient care providers often have minimal participation in postfall reviews. This study suggests they can provide insight into why patients fall. Additionally, both registered nurses and unlicensed providers describe barriers that often impede their ability to work as a team to prevent patient falls. Findings from this study identified the need for the patient care team to strengthen collaborative work to create safer patient environments.
Viral load assay performs comparably to early infant diagnosis assay to diagnose infants with HIV in Mozambique: a prospective observational study
Authors: Vubil Adolfo , Nhachigule Carina , Loquiha Osvaldo , Meggi Bindiya , Mabunda Nedio , Bollinger Timothy , Sacks Jilian A , Jani Ilesh , Vojnov Lara
Published: January 2020

Introduction

Viral load testing is essential to manage HIV disease, especially in infants and children. Early infant diagnosis (EID) is performed using nucleic‐acid testing in children under 18 months. Resource‐limited health systems face severe challenges to scale‐up both viral load and EID to unprecedented levels. Streamlining laboratory systems would be beneficial to improve access to quality testing and to increase efficiency of antiretroviral treatment programmes. We evaluated the performance of viral load testing to serve as an EID assay in children younger than 18 months.

Methods

This study was an observational, prospective study, including children between one and 18 months of age who were born to HIV‐positive mothers in 134 health facilities in Maputo City and Maputo Province, Mozambique. Dried blood spot specimens from heel or toe pricks were collected between January and April 2018, processed using SPEX buffer for both assays, and tested for routine EID and viral load testing using the Roche CAP/CTM HIV‐1 Qualitative v2 and Roche CAP/CTM HIV‐1 Quantitative v2 assays respectively. The sensitivity, specificity and positive and negative predictive values were estimated using the EID results as the reference standard.

Results

A total of 1021 infants were included in the study, of which 47% were female. Over 95% of mothers and children were on antiretroviral treatment or received antiretroviral prophylaxis respectively. The sensitivity and specificity of using the viral load assay to detect infection were 100% (95% CI: 96.2 to 100%) and 99.9% (95% CI: 99.4 to 100%). The positive and negative predictive values were 99.0% (95% CI: 94.3 to 100%) and 100% (95% CI: 99.6 to 100%). The McNemar’s test was 1.000 and Cohen’s kappa was 0.994.

Conclusions

The comparable performance suggests that viral load assays can be used as an infant diagnostic assay. Infants with either low levels of viraemia or high cycle threshold values should be repeat tested to ensure the result is truly positive prior to treatment initiation, regardless of assay used. Viral load assays could replace traditional EID testing, substantially streamlining molecular laboratory services for children and lowering costs, with the additional advantage of providing baseline viral load results for antiretroviral treatment management.
Radiosynthesis of the 11C‐methyl derivative of LBQ657 for PET investigation of the neprilysin inhibitor sacubitril
Authors: Teyssier Valentin R. , Simard José‐Mathieu , Dornan Mark H. , Tournoux François , DaSilva Jean N.
Published: January 2020

Neprilysin, also known as neutral endopeptidase, is a cell surface membrane metalo‐endopeptidase that cleaves various peptides. Altered neprilysin expression has been correlated with various cancers and cardiovascular diseases. In this work, we present the radiosynthesis of the novel O‐11C‐methylated derivative of LBQ657 (a potent neprilysin inhibitor). (2R,4S)‐5‐(Biphenyl‐4‐yl)‐4‐[(3‐carboxypropionyl)amino]‐2‐methylpentanoic acid [11C]methyl ester ([11C]MeOLBQ) is an analog of sacubitril where the alkyl ester is a 11C‐methyl instead of an ethyl. [11C]MeOLBQ was produced in a one‐pot two‐step synthesis. The O‐11C‐methylation of the pentanoic acid part was done with [11C]methyl triflate followed by the deprotection of the tert‐butyl ester precursor in acidic conditions. [11C]MeOLBQ ([11C]7) was produced in 9.5 ± 2.5% RCY (25 ± 6% decay‐corrected from [11C]CO2, n = 3) high molar activity 348 ± 100 GBq/μmol (9425 ± 2720 mCi/μmol) at EOS, in high chemical (>95%) and radiochemical (>99%) purities. The total synthesis time including HPLC purification and reformulation was 29 minutes. To our knowledge, this is the first PET‐labeled analog of the clinically used NEP inhibitor sacubitril.
Organ preservation following radiation therapy and concurrent intra‐arterial low dose cisplatin infusion for advanced T2 and T3 laryngeal cancer: Long‐term clinical results from a pilot study
Authors: Ono Takeharu , Tanaka Norimitsu , Tanoue Syuichi , Miyata Yusaku , Muraki Koichiro , Tsuji Chiyoko , Ogo Etsuyo , Aso Takeichiro , Chitose Shun‐ichi , Shin Buichiro , Kakuma Tatsuyuki , Etoh Hidehiro , Hattori Chikayuki , Abe Toshi , Umeno Hirohito
Published: January 2020

Background

This pilot study evaluated the long‐term outcomes of patients with advanced T2 or T3 squamous cell carcinoma of the larynx (SCC‐L) who were treated with selective intra‐arterial cisplatin and concomitant radiotherapy (RADPLAT).

Methods

We retrospectively investigated the data of 49 patients with advanced T2 or T3 SCC‐L who received a RADPLAT regimen with low‐dose cisplatin.

Results

The 5‐year locoregional control, disease‐specific survival, and overall survival rates were 83.3%, 88.1%, and 82.6%, respectively, while the 5‐year freedom from laryngectomy, laryngectomy‐free survival, and laryngo‐esophageal dysfunction‐free survival rates were 89.6%, 79.4%, and 77.1%, respectively. The incidences of grade 3‐4 hematologic and nonhematologic toxicities were 18% and 6%, respectively. Although two patients (4%) developed late toxicities within 5 years following RADPLAT, no other events were noted beyond 5 years.

Conclusion

This pilot study demonstrated that RADPLAT is feasible and safe and yielded favorable survival outcomes and functional laryngeal preservation in patients with advanced T2 or T3 SCC‐L.

Level of evidence

3
Microplastic prevalence in two fish species in two U.S. reservoirs
Authors: Hurt Raven , O'Reilly Catherine M. , Perry William L.
Published: January 2020

Microplastics in the environment can impact feeding and physiological functions of organisms. Most studies have focused on marine systems, and studies of lacustrine organisms are less common. We examined microplastic concentration in 72 gizzard shad and 24 largemouth bass from two agricultural reservoirs in the midwestern U.S.A. with differing shoreline development. Microplastics were found in 100% of the fish, with 1–49 No. Fish−1, independent of shoreline development. Bass had higher concentrations overall than shad. For bass, microplastics were more concentrated in the guts rather than gills, but the opposite was the case for shad, suggesting that feeding guild may influence where microplastics accumulate in fishes. The prevalence and concentrations reported here are greater than reported in marine systems and higher than reported in riverine studies. Our results underscore the ubiquitous distribution of microplastics and suggest that lake ecosystems in agricultural landscapes may be particularly susceptible to microplastic contamination.
Wear study and EHD lubrication analysis on connecting rod big end bearings of off‐highway application engine
Authors: Nayak Nagaraj , Rane Santosh , A Anarghya , Kushwaha Rohit
Published: January 2020

The connecting rod big end bearings are under dynamic lubrication during working cycle, and in most of the time, the con rod is subjected to compressive stress. The conventional method of performing an EHL analysis on a bearing involves development of complex mathematical equations and simplification of actual physical model. This paper presents a methodology to model and simulate the elastohydrodynamic lubrication and wear study of connecting rod big end bearings of off‐highway application engine using the application of computational fluid dynamics (CFD) and computational structural dynamics (CSD) approaches. The pressure field for a full journal bearing operating under laminar flow regime with various eccentricities was obtained by CFD, and fluid pressure distribution and deformation in the bearing liner due to pressure were evaluated using FSI approach. Relevant parameters of lubrication characteristics were analyzed to optimize the eccentricity value. The maximum bearing load value of 21 kN was noticed at TDC position for the optimum eccentricity. The load distribution indicated critical points in the bearing, and the data obtained from bearing load and sliding velocity of journal were used in Archard's wear relation to determine the wear depth along the bearing width. The simulated wear results were compared with three‐cylinder off‐highway application engine con rod big end bearings, which ran for 1000 hours at full load condition, and satisfactory agreement was observed between experiment and simulation values.
Matching Static and Dynamic Compliance of Small‐Diameter Arteries, with Poly(lactide‐co‐caprolactone) Copolymers: In Vitro and In Vivo Studies
Authors: Behr Jean‐Marc , Irvine Scott Alexander , Thwin Chaw‐Su , Shah Ankur Harish , Bae Min‐Chul Kraun , Zussman Eyal , Venkatraman Subbu
Published: January 2020

Mechanical mismatch between vascular grafts and blood vessels is a major cause of smaller diameter vascular graft failure. To minimize this mismatch, several poly‐l‐lactide‐co‐ε‐caprolactone (PLC) copolymers are evaluated as candidate materials to fabricate a small diameter graft. Using these materials, tubular prostheses of 4 mm inner diameter are fabricated by dip‐coating. In vitro static and dynamic compliance tests are conducted, using custom‐built apparatus featuring a closed flow system with water at 37 °C. Grafts of PLC monomer ratio of 50:50 are the most compliant (1.56% ± 0.31∙mm Hg−2), close to that of porcine aortic branch arteries (1.56% ± 0.43∙mm Hg−2), but underwent high continuous dilatation (87 µm min−1). Better matching is achieved by optimizing the thickness of a tubular conduit made from 70:30 PLC grafts. In vivo implantation and function of a PLC 70:30 conduit of 150 µm wall‐thickness (WT) are tested as a rabbit aorta bypass. An implanted 150 µm WT PLC 70:30 prosthesis is observed over 3 h. The recorded angiogram shows continuous blood flow, no aneurysmal dilatation, leaks, or acute thrombosis during the in vivo test, indicating the potential for clinical applications.
Textile‐integrated waveguide switch for ISM band 5.8 GHz
Authors: Cupal Miroslav , Raida Zbyněk
Published: January 2020

In this article, a textile‐integrated waveguide (TIW) switch designed for the ISM band 5.8 GHz is presented. Conductive surfaces of the switch are manufactured by screen printing using a silver paste, and side walls of the TIW are sewed by a conductive thread. The switch is based on a common TIW T‐divider which is completed by controllable conductive posts in both branches. The controllable posts can be switched from the high‐impedance state to the low impedance state (and vice versa) by connecting or disconnecting them to the conductive layers by PIN diodes. Transmissions of the open branch of the switch and the closed one are |S21| = −1.5 dB and |S31| = −14.9 dB, respectively. If the manufactured switch is completed by transitions from TIW to coaxial line, the transitions of the open branch and the closed one are|S21| = −6.2 dB and |S31| = −15.6 dB, respectively.
Ultrawideband planar bow‐tie with curved directive strips for gain enhancement
Authors: Howlett Matthew , Park Hong S. , Hong Sun K. , Wheeler Edward
Published: January 2020

A novel ultrawideband planar bow‐tie antenna with curved directive strips for gain enhancement is presented. The strips direct radiation to the plane perpendicular to the antenna, increasing the broadside gain over the antenna's impedance bandwidth with no increase to the radius of the sphere containing the antenna. To facilitate the use of the proposed antenna in various application scenarios, three different feeding mechanisms are presented. Accordingly, three antennas, each with their respective feeding structures are designed and tested via simulation and measurement with the results for each showing enhanced broadside gain over the antenna bandwidth.
NMR signal processing, prediction, and structure verification with machine learning techniques
Authors: Cobas Carlos
Published: January 2020

Machine learning (ML) methods have been present in the field of NMR since decades, but it has experienced a tremendous growth in the last few years, especially thanks to the emergence of deep learning (DL) techniques taking advantage of the increased amounts of data and available computer power. These algorithms are successfully employed for classification, regression, clustering, or dimensionality reduction tasks of large data sets and have been intensively applied in different areas of NMR including metabonomics, clinical diagnosis, or relaxometry. In this article, we concentrate on the various applications of ML/DL in the areas of NMR signal processing and analysis of small molecules, including automatic structure verification and prediction of NMR observables in solution.
Computational and dynamic NMR investigation of 2,2‐dimesityl‐1,1,1,3,3,3‐hexamethyltrisilane
Authors: Winchester William R. , Seymour Jenna
Published: January 2020

The structure and rotational barrier for the mesityl‐silicon bond of 2,2‐dimesityl‐1,1,1,3,3,3‐hexamethyltrisilane have been investigated by 1H‐ and 13C‐variable temperature nuclear magnetic resonance (NMR) as well as by density functional theory structural calculations. The calculations show that the lowest energy structure has C2 symmetry with nonequivalent ortho methyl groups, consistent with the crystal structure and solution NMR. The nonequivalent ortho methyl groups exchange through a Cs transition state with a calculated relative free energy of 11.0 kcal mol−1. The barrier for this rotation found by dynamic NMR is 13.4 ± 0.2 kcal mol−1 at 298 K.
Subsoil classification and geotechnical zonation for Guadalajara City, México: Vs30, soil fundamental periods, 3D structure and profiles
Authors: Ramírez Gaytan Alejandro , Flores Estrella Hortencia , Preciado Adolfo , Bandy William L. , Lazcano Salvador , Alcántara Nolasco Leonardo , Aguirre González Jorge , Korn Michael
Published: January 2020

Guadalajara, Jalisco, is the second largest city in Mexico with around 4.5 million inhabitants. A high seismic hazard exists in the city due to forces produced by the interaction between the Rivera, Cocos and North American plates and the smaller Jalisco Block. Guadalajara is one of the largest cities built over pumice soil deposits. Furthermore, the near‐surface phreatic level causes a high susceptibility to liquefaction. All these features can cause extreme earthquake site effects. Due to the fragile inner structure of pumice sands, traditional geotechnical tests are inappropriate to characterize the seismic response. Therefore, we propose the use of surface wave analysis methods (multichannel analysis of surface waves and refraction microtremor), which we applied in 33 sites to define the soil classification in terms of VS30 (the average shear wave velocity between the surface and 30 m depth), the bedrock depth and the fundamental period. From the soil classification, we construct a microzonation map consisting of four geotechnical zones, which we superimpose on the known construction systems within the city. The comparison between the construction period of the buildings and the fundamental frequencies of the soil indicates a high vulnerability to resonance in 1‐ to 4‐storied old buildings constructed of adobe and unreinforced masonry within zones II and III, followed by a medium vulnerability to seismic resonance in compact buildings of 1–4 stories within zone I and 1–12 stories within zones II and IV.
PolyMPC: An efficient and extensible tool for real‐time nonlinear model predictive tracking and path following for fast mechatronic systems
Authors: Listov Petr , Jones Colin
Published: January 2020

This paper presents PolyMPC, an open‐source C++ library for pseudospectral‐based real‐time predictive control of nonlinear systems. It provides a necessary background on the computational aspects of the pseudospectral approximation of optimal control problems and explains how various model predictive control and parameter estimation algorithms can be implemented using the software. We discuss the key algorithmic modules and architectural features of the PolyMPC library. The workflow of a path following controller design for a highly nonlinear mechatronic system is demonstrated in a tutorial example. Another example illustrates how the core functionality might be used to approximate and solve a custom optimal control problem.
Does the guerrilla win, if he does not lose? Advertising media practitioners' views on guerrilla marketing challenges and potential negative consequences
Authors: Roux Thérèse
Published: January 2020

The purpose of this article is to offer an advertising media practitioners' perspective on guerrilla marketing challenges and negative consequences. In‐depth qualitative interviews were conducted with practitioners with extensive experience in guerrilla marketing campaigns in the South African context. Two themes and four related subthemes emerged from the data, namely, economic implications and potential societal impact of guerrilla marketing. The result and guidelines to evaluate guerrilla marketing challenges and potential negative consequences to consider shed some light for businesses employing or considering this platform. Marketers should not only focus on the advantageous guerrilla effects but must also be aware of the potential disadvantageous effects on consumers, the market, and society. Due to the unconventional and out‐of‐home nature of guerrilla activities, ethical, legal, and social boundaries must be balanced with potential positive outcomes. The current literature focussed predominately on the consumers' positive response towards guerrilla marketing. This article bridges a gap in the existing literature and is one the first studies on the potential negative consequences and challenges of guerrilla marketing campaigns.
Redox polymers incorporating pendant 6‐oxoverdazyl and nitronyl nitroxide radicals
Authors: Anghel Michael , Magnan François , Catingan Sara D. , McCready Matthew A. , Aawani Elaheh , Wong Victor , Singh Deepa , Fanchini Giovanni , Gilroy Joe B.
Published: January 2020

Polymers comprised of redox‐active organic radicals have emerged as promising materials for use in a variety of organic electronics, including fast‐charging batteries. Despite these advances, relatively little attention has been focused on the diversification of the families of radicals that are commonly incorporated into polymer frameworks, with most radical polymers being comprised of nitroxide radicals. Here, we report two new examples prepared via ring‐opening methathesis polymerization containing 6‐oxoverdazyl and nitronyl nitroxide radicals appended to their backbones. The polymerization reaction and optoelectronic properties were explored in detail, revealing high radical content and redox activity that may be advantageous for their use as semiconducting thin films. Initial studies revealed that current–voltage curves obtained from thin films of the title polymers exhibited memory effects making them excellent candidates for use in resistive memory applications. © 2020 Wiley Periodicals, Inc. J. Polym. Sci. 2020, 58, 309–319
Atmospheric pressure chemical ionization mass spectrometry at low flow rates: Importance of ion source housing
Authors: Strmeň Timotej , Vrkoslav Vladimír , Bosáková Zuzana , Cvačka Josef
Published: January 2020

Rationale

Hyphenation of atmospheric pressure chemical ionization (APCI) mass spectrometry with capillary and micro high‐performance liquid chromatography (HPLC) is attractive for many applications, but reliable ion sources dedicated to these conditions are still missing. There are a number of aspects to consider when designing such an ion source, including the susceptibility of the ionization processes to ambient conditions. Here we discuss the importance of ion source housing for APCI at low flow rates.

Methods

Selected compounds dissolved in various solvents were used to study ionization reactions at 10 μL/min flow rate. APCI spectra were generated using the Ion Max‐S source (Thermo Fisher Scientific) operated with or without the ion source housing.

Results

The APCI spectra of most compounds measured in the open and enclosed ion sources were markedly different. The differences were explained by water and oxygen molecules that entered the plasma region of the open ion source. Water tended to suppress charge transfer processes while oxygen diminished electron capture reactions and prevented the formation of acetonitrile‐related radical cations useful for localizing double bonds in lipids. The effects associated with the ion source housing were significantly less important for compounds that are easy to protonate or deprotonate.

Conclusions

The use of ion source housing prevented alternative ionization channels leading to unwanted or unexpected ions. Compared with the conventional flow rate mode (1 mL/min), the effects of ambient air components were significantly higher at 10 μL/min, emphasizing the need for ion source housing in APCI sources dedicated to low flow rates.
Wind effects on soil thermal properties measured by the dual‐probe heat pulse method
Authors: Sang Yujie , Liu Gang , Horton Robert
Published: January 2020

When a dual‐probe heat pulse (DPHP) sensor is installed in soil near the soil–atmosphere interface, the basic assumptions of the infinite line heat source (ILS) model and its improvement, the infinite line heat source model with an adiabatic boundary condition (ILS‐ABC) might not be satisfied because of wind. This study aims to explore the effects of wind on DPHP measurements and to compare the performance of the ILS and ILS‐ABC models at different values of wind velocity (υ) and burial depth (d). Our study shows that the results of laboratory experiments, COMSOL simulations, and field experiments are consistent with each other. For dry sand with d ≤ 4 mm, the effects of wind is non‐negligible at υ ≥ 3.5 m s−1 and the DPHP method does not provide accurate estimations whether the ILS model or the ILS‐ABC model is used. Field experiments are prone to large background temperature fluctuations, which can cause a commonly used linear detrending method to perform poorly. In general, at υ < 2.7 m s−1 in field and d = 5 mm, the ILS‐ABC model provides more accurate estimations with relative errors of <15% in thermal conductivity and relative errors of <9% in heat capacity.
Quicker detection risk‐adjusted cumulative sum charting procedures
Authors: Fatt Gan Fah , Sheng Yuen Jing , Knoth Sven
Published: January 2020

When a patient is operated on, the surgical outcome depends on two major factors: (i) the patient's health condition and (ii) the surgical process comprising the surgeon, the supporting staff, operating environment, and equipment. An outcome is usually represented by one if a patient dies within 30 days of an operation and zero otherwise. Another method of measuring the outcome is to use survival time with truncation on the 30th day for monitoring purposes. In order to monitor a surgical process effectively, the health condition of a patient must be taken into consideration. This is usually done using a log‐likelihood ratio statistic based on an outcome, that is, risk adjusted according to the health condition of the patient. The 30‐day wait results in delay in signaling when a deterioration occurs. The consequence of having to wait even though a death has occurred is the potential loss of lives because of delay in signaling. Regular updating of patients' information can improve the sensitivity of a charting procedure. The main objective of this article is to develop and study the class of risk‐adjusted cumulative sum procedures that are updated on a regular basis based on patients' current conditions, without having to wait 30 days. Our study shows that these charts do in fact signal earlier and there are differences among the various updating techniques and monitoring statistics.
Crowdsourcing as a mode of open innovation: Exploring drivers of success of a multisided platform through system dynamics modelling
Authors: Vignieri Vincenzo
Published: January 2020

This article aims to explore drivers of success of a crowdsourcing platform. The study conceptualizes crowdsourcing as a mode of open innovation and places such a concept within the context of the sharing economy. Upon this framework, the paper analyses the case of InnoCentive, a successful crowdsourcing platform where innovation‐driven organizations search for solutions to their R&D tasks. The system dynamics model frames main InnoCentive business processes and offers a causal perspective on the relationships between platform performance—in terms of users base—and resources structure. The discussion on simulation outputs is carried out through a dynamic performance management view of performance, so as to highlight which factors are crucial to lead crowdsourcing platform to be effective in supporting seekers organization to innovate in an open way, as well as to understand how platform managers may improve such a problem‐solving process.
Einfluss der Dämpfungsmodellierung auf die Beschleunigungsantwort eines erdbebenerregten Stahlrahmens
Authors: Gremer Nadia , Adam Christoph , Moschen Lukas , Medina Ricardo A.
Published: January 2020

Im Rahmen einer Fallstudie befasst sich dieser Aufsatz mit der Auswirkung unterschiedlicher Dämpfungsansätze auf die berechnete Beschleunigungsantwort eines ebenen, regelmäßigen elastischen Stahlrahmens unter Erdbebenanregung. Es wird dabei nicht nur, so wie im Erdbebeningenieurwesen üblich, die Vergrößerung der horizontalen Bodenbeschleunigung betrachtet, sondern zusätzlich auch die Vergrößerung der vertikalen Bodenbeschleunigung. Die Ergebnisse zeigen, dass bei der Verwendung von Rayleigh‐Dämpfung gemäß der ingenieurmäßigen und wissenschaftlichen Praxis die vertikale Bodenbeschleunigung rechnerisch nur sehr wenig vergrößert wird, da die vertikalen Moden zu stark gedämpft werden. Das erklärt die bisherige Annahme, dass die Vergrößerung der vertikalen Beschleunigung vernachlässigbar ist. Im Gegensatz dazu wird mit Rayleigh‐Dämpfung auf Grundlage der effektiven vertikalen Massenpartizipation sowohl die horizontale als auch die vertikale Tragwerksbeschleunigung überschätzt. Die Implementierung der inhärenten Dämpfung im Rechenmodell in Form von modaler Dämpfung führt hingegen zu einer realistischen rechnerischen Vorhersage der Beschleunigungsantwort in beiden Richtungen.
Uber – Mission Bay Campus, San Francisco
Authors: Oppe Matthias , Grün Stefanie
Published: January 2020

Derzeit entsteht in San Francisco (USA) der neue Hauptfirmensitz des Fahrdienstes Uber. Zentraler Bestandteil des Entwurfs sind zwei kubische, durch Brückenkonstruktionen miteinander verbundene, sechs‐ bzw. elfgeschossige Baukörper mit transparenter Gebäudehülle. Das Tragsystem der ca. 6 000 m2 großen Hauptfassade, die nicht als thermische Hülle dient, besteht aus Stahlträgern, die als Unterkonstruktion für Aluminiumelemente und Öffnungsflügel fungieren.

Die große Herausforderung bei der Entwicklung und Planung der Außenhüllen bestand darin, anspruchsvolle Fassadensysteme mit hohen architektonischen Anforderungen sowie einer maximalen Transparenz auszulegen. Ebenso mussten bei der Entwicklung der Fassadenkonstruktion die aufgrund der geografischen Lage hohen seismischen Beanspruchungen und die daraus resultierenden Verformungen bzw. Kräfte berücksichtigt werden.
Herleitung des Überfestigkeitsbeiwerts auf Basis statistischer Kennwerte europäischer Baustähle
Authors: Gündel Max
Published: January 2020

Bei der dissipativen Bemessung von Stahlbauten gegen Erdbebenlasten sind Kapazitätsregeln zu beachten, die eine Kontrolle des plastischen Mechanismus sicherstellen sollen. Hierfür müssen nicht dissipative Bauteile eine Überfestigkeit gegenüber den dissipativen Bereichen besitzen. Streuungen der Streckgrenze von Baustahl werden in DIN EN 1998‐1 durch den Überfestigkeitsbeiwert γov mit einem empfohlenen Wert von 1,25 erfasst. Aktuelle Messdaten zeigen allerdings, dass die tatsächliche Streckgrenze von Baustahl, gerade bei Stahlsorten mit einer niedrigen Nennfestigkeit, häufig wesentlich höher ist. In diesem Beitrag werden neue Messdaten zur Streckgrenze von Stahlsorten aus Europa ausgewertet und mit statistischen Kennwerten aus der Literatur verglichen. Auf Basis eines neuen probabilistischen Modells für die Streckgrenze wird schließlich ein stahlsortenabhängiger Überfestigkeitsbeiwert hergeleitet, der Einzug in den neuen deutschen Nationalen Anhang DIN EN 1998‐1/NA:2018 gehalten hat.
Das Vereinheitlichte Vorschriftenwerk für den Stahlbau in der DDR
Authors: Graße Wolfgang , Lutteroth Ascan , Riedeburg Klaus
Published: January 2020

Im vorliegenden Beitrag wird ein kurzer Überblick über die Entstehung, die Prinzipien und den Aufbau des Vereinheitlichten Vorschriftenwerks für den Stahlbau in der DDR gegeben. Wichtige inhaltliche Neuerungen, vor allem hinsichtlich des rationellen Stahleinsatzes, werden dargestellt.
Characterization of Prata Banana (Musa AAB‐Prata) Starch: Native and Modified by Annealing
Authors: Almeida Maria Climene Bezerra de Medeiros , Costa Sabrina dos Santos , Cavalcanti Mônica Tejo , Almeida Eveline Lopes
Published: January 2020

Prata variety banana starch is little known and has great economic potential due to its extensive cultivation in developing countries. This study characterizes this native starch and modifies by annealing at different temperatures (45, 50, and 55 °C). The native starch presents a high apparent amylose content (46.67%), besides it showing granules of several sizes and shapes containing rounded ends, which remain unchanged with the annealing. The weaker crystals are seen to be strengthened by the treatments at 50 and 55 °C, since the gelatinization onset and peak temperature increase. It also is possible to verify that the molecular order of the double amylopectin helices (ΔH) remains unaltered, but the uniformity of the molecular structure (Tc − To) increases. Regarding the pasting properties, annealing contributes to improving the paste's stability to heat and shear, but contributes to decreasing the stability of cooled starch paste. In addition, annealing increases the paste clarity and the least gelation concentration. Native starch stands out by its high resistant starch content (34.71%), which can be increased to 74.5% through annealing at 55 °C.
Structural analysis and optimization of a tethered swept wing for airborne wind energy generation
Authors: Candade Ashwin A. , Ranneberg Maximilian , Schmehl Roland
Published: January 2020

In this paper, we present an aero‐structural model of a tethered swept wing for airborne wind energy generation. The carbon composite wing has neither fuselage nor actuated aerodynamic control surfaces and is controlled entirely from the ground using three separate tethers. The computational model is efficient enough to be used for weight optimisation at the initial design stage. The main load‐bearing wing component is a nontypical “D”‐shaped wing‐box, which is represented as a slender carbon composite shell and further idealised as a stack of two‐dimensional cross section models arranged along an anisotropic one‐dimensional beam model. This reduced 2+1D finite element model is then combined with a nonlinear vortex step method that determines the aerodynamic load. A bridle model is utilised to calculate the individual forces as a function of the aerodynamic load in the bridle lines that connect the main tether to the wing. The entire computational model is used to explore the influence of the bride on the D‐box structure. Considering a reference D‐box design along with a reference aerodynamic load case, the structural response is analysed for typical bridle configurations. Subsequently, an optimisation of the internal geometry and laminate fibre orientations is carried out using the structural computation models, for a fixed aerodynamic and bridle configuration. Aiming at a minimal weight of the wing structure, we find that for the typical load case of the system, an overall weight savings of approximately 20% can be achieved compared with the initial reference design.
Analyzing the impact of organic certification on product and sustainable attributes on the importance of organic food certification in Thailand: Mediating role of perceived benefits of organic food
Authors: Mitprasat Maneerat , Horakul Pissanu , Umam Rofiqul
Published: January 2020

Time has come to cope with severe food shortage as well as quality which is resulting in the stunted growth of children and many other diseases. The answer to all these problems lies in organic food which is becoming increasingly common in developed countries as many brands are moving toward organic certification of their products as well as sustainable attributes. This study has aimed to analyze the importance of the role of organic certification of products as well as sustainable attributes in Thailand. Moreover, this study has also assessed the mediating role of perceived benefits of organic food in respective relationships. Around 301 residents of Thailand were included in data gathering and analysis of the study which was later run on SPSS and AMOS. Descriptive tests, CFA, and SEM were run for data screening, validity, and hypotheses testing, respectively. The results have shown that certification of product attributes has a significant impact on the importance of organic certification while sustainable attributes do not have a significant effect on the same. The mediating role of perceived benefits has been proved in both relationships. This study is novel because no previous study has analyzed the mediating role of perceived benefits in given relationships. This study has important implications for theory, management of restaurants, food sector and government of Thailand's.
Genetic analysis of wheat sensitivity to the ToxB fungal effector from Pyrenophora tritici-repentis, the causal agent of tan spot
Authors: Corsi Beatrice , Percival-Alwyn Lawrence , Downie Rowena C. , Venturini Luca , Iagallo Elyce M. , Campos Mantello Camila , McCormick-Barnes Charlie , See Pao Theen , Oliver Richard P. , Moffat Caroline S. , Cockram James
Published: January 2020

Key message

Genetic mapping of sensitivity to thePyrenophora tritici-repentiseffector ToxB allowed development of a diagnostic genetic marker, and investigation of wheat pedigrees allowed transmission of sensitive alleles to be tracked.

Tan spot, caused by the necrotrophic fungal pathogenPyrenophora tritici-repentis, is a major disease of wheat (Triticum aestivum). Secretion of theP. tritici-repentiseffector ToxB is thought to play a part in mediating infection, causing chlorosis of plant tissue. Here, genetic analysis using an association mapping panel (n = 480) and a multiparent advanced generation intercross (MAGIC) population (nfounders = 8,nprogeny = 643) genotyped with a 90,000 feature single nucleotide polymorphism (SNP) array found ToxB sensitivity to be highly heritable (h2 ≥ 0.9), controlled predominantly by theTsc2locus on chromosome 2B. Genetic mapping ofTsc2delineated a 1921-kb interval containing 104 genes in the reference genome of ToxB-insensitive variety ‘Chinese Spring’. This allowed development of a co-dominant genetic marker forTsc2allelic state, diagnostic for ToxB sensitivity in the association mapping panel. Phenotypic and genotypic analysis in a panel of wheat varieties post-dated the association mapping panel further supported the diagnostic nature of the marker. Combining ToxB phenotype and genotypic data with wheat pedigree datasets allowed historic sources of ToxB sensitivity to be tracked, finding the variety ‘Maris Dove’ to likely be the historic source of sensitiveTsc2alleles in the wheat germplasm surveyed. Exploration of theTsc2region gene space in the ToxB-sensitive line ‘Synthetic W7984’ identified candidate genes for future investigation. Additionally, a minor ToxB sensitivity QTL was identified on chromosome 2A. The resources presented here will be of immediate use for marker-assisted selection for ToxB insensitivity and the development of germplasm with additional genetic recombination within theTsc2region.
Value dividends, the Harsanyi set and extensions, and the proportional Harsanyi solution
Authors: Besner Manfred
Published: January 2020

A new concept for TU-values, called value dividends, is introduced. Similar to Harsanyi dividends, value dividends are defined recursively and provide new characterizations of values from the Harsanyi set. In addition, we generalize the Harsanyi set where each of the TU-values from this set is defined by the distribution of the Harsanyi dividends via sharing function systems and give an axiomatic characterization. As a TU value from the generalized Harsanyi set, we present the proportional Harsanyi solution, a new proportional solution concept. A new characterization of the Shapley value is proposed as a side effect. None of our characterizations uses additivity.
Technische Entwicklungen und Möglichkeiten im Markscheidewesen
Authors: Tscharf Alexander
Published: January 2020

Das unentwegte Aufkommen und die stetige Entwicklung neuer Vermessungssensorik, gepaart mit der digitalen Vernetzung des täglichen Lebens und nahezu aller modernen Produktionsprozesse, lässt naturgemäß auch das Tätigkeitsfeld der verantwortlichen Markscheider nicht unberührt.

Obwohl anlässlich mehrerer Jubiläen erfahrener Forscher und Hochschullehrer verfasst, will der vorliegende Beitrag jedoch keine reumütige Rückschau halten, sondern vielmehr aktuelle Entwicklungen und daraus folgende Möglichkeiten präsentieren. In diesem Zusammenhang werden jedoch auch damit einhergehende Herausforderungen aufgezeigt sowie ein Blick in die Zukunft gewagt, von dem auch die gesetzlichen Aufgaben des verantwortlichen Markscheiders nicht ausgeschlossen werden sollen.
Correction to: Portal flow modulation in living donor liver transplantation: review with a focus on splenectomy
Authors: Yoshizumi Tomoharu , Mori Masaki
Published: January 2020

The article Portal flow modulation in living donor liver transplantation: review
Micromachined Waveguide Interposer for the Characterization of Multi-port Sub-THz Devices
Authors: Gomez-Torrent Adrian , Oberhammer Joachim
Published: January 2020

This paper reports for the first time on a micromachined interposer platform for characterizing highly miniaturized multi-port sub-THz waveguide components. The reduced size of such devices does often not allow to connect them to conventional waveguide flanges. We demonstrate the micromachined interposer concept by characterizing a miniaturized, three-port, 220–330-GHz turnstile orthomode transducer. The interposer contains low-loss micromachined waveguides for routing the ports of the device under test to standard waveguide flanges and integrated micromachined matched loads for terminating the unused ports. In addition to the interposer, the measurement setup consists of a micromachined square-to-rectangular waveguide transition. These two devices enable the characterization of such a complex microwave component in four different configurations with a standard two-port measurement setup. In addition, the design of the interposer allows for independent characterization of its sub-components and, thus, for accurate de-embedding from the measured data, as demonstrated in this paper. The measurement setup can be custom-designed for each silicon micromachined device under test and co-fabricated in the same wafer due to the batch nature of this process. The solution presented here avoids the need of CNC-milled test-fixtures or waveguide pieces that deteriorate the performance of the device under test and reduce the measurement accuracy.