bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystallization of Cocoa Butter in Cocoa Powder
Authors: Palmieri Paige A. , Hartel Richard W. 
Published: June 2019

AbstractCocoa powder quality is determined by its color, flavor, dispersion, and flow properties, which can be controlled via tempering. Design of a cocoa powder tempering profile, however, requires that the mechanism of cocoa butter crystallization in cocoa powder be fully understood. Low‐fat (8–12%) and high‐fat (20–24%) cocoas were sourced from two commercial manufacturers at varying degrees of alkalization and compared with two commercial cocoa butters. Unrefined paired cocoa powders and cocoa butters sampled from the hydraulic press were also evaluated. Isothermal crystallization kinetics and polymorphism of cocoa powders and cocoa butters were compared at 18, 21, and 24 °C using a direct time‐domain nuclear magnetic resonance method, differential scanning calorimetry, and x‐ray diffraction. Crystallization was also studied under dynamic tumbling conditions. It was found that cocoa butter in cocoa powder was nucleated by the cocoa powder matrix and transitioned to higher‐stability polymorphs more rapidly than bulk cocoa butters. High‐fat cocoas also exhibited enhanced crystallization kinetics relative to low‐fat cocoas, showing that differences in the cocoa microstructure may influence crystallization behavior. Notably, alkalization did not significantly affect the crystallization behavior of most cocoa powders. Finally, it was found that tumbling conditions led to crystallization of βV and that caking, especially of high‐fat cocoas, could be reduced by a static low‐temperature hold step prior to tumbling. Overall, these results demonstrated that crystallization of cocoa butter in cocoa powder is influenced both by the intrinsic attributes of the cocoa powder as well as the conditions of the tempering process.
Probing Deviation of Adhered Membrane Dynamics between Reconstituted Liposome and Cellular System
Authors: Mondal Prasenjit , Chowdhury Rajdeep , Nandi Somen , Amin Md. Asif , Bhattacharyya Kankan , Ghosh Surajit 
Published: June 2019

AbstractThe dynamics of cell‐cell adhesion are complicated due to complexities in cellular interactions and intra‐membrane interactions. In the present work, we have reconstituted a liposome‐based model system to mimic the cell‐cell adhesion process. Our model liposome system consists of one fluorescein‐tagged and one TRITC (tetramethyl‐rhodamine isothiocyanate)‐tagged liposome, adhered through biotin‐neutravidin interaction. We monitored the adhesion process in liposomes using Förster Resonance Energy Transfer (FRET) between fluorescein (donor) and TRITC (acceptor). Occurrence of FRET is confirmed by the decrease in donor lifetime as well as distinct rise time of the acceptor fluorescence. Interestingly, the acceptor's emission exhibits fluctuations in the range of ≈3±1 s. This may be attributed to structural oscillations associated in two adhered liposomes arising from the flexible nature of biotin‐neutravidin interaction. We have compared the dynamics in a cell‐mimicking liposome system with that in an in vitro live cell system. In the adhered live cell system, we used CPM (7‐diethylamino‐3‐(4‐maleimido‐phenyl)‐4‐methylcoumarin, donor) and nile red (acceptor), which are known to stain the membrane of CHO (Chinese Hamster Ovary) cells. The dynamics of the adhered membranes of two live CHO cells were observed through FRET between CPM and nile red. The acceptor fluorescence intensity exhibits an oscillation in the time‐scale of ≈1±0.75 s, which is faster compared to the reconstituted liposome system, indicating the contributions and involvement of multiple dynamic protein complexes around the cell membrane. This study offers simple reconstituted model systems to understand the complex membrane dynamics using a FRET‐based physical chemistry approach.
Identification and elucidation of proline‐rich antimicrobial peptides with enhanced potency and delivery
Authors: Lai Pin‐Kuang , Tresnak Daniel T. , Hackel Benjamin J. 
Published: June 2019

AbstractProline‐rich antimicrobial peptides (PrAMPs) kill bacteria via a nonlytic mechanism in which they permeate through the outer membrane, utilize protein‐mediated transport across the inner membrane, and target the ribosome to inhibit protein synthesis. We previously reported that substitutions of oncocin () with a pair of cationic residues improved the antimicrobial activity. In this study, we applied the design protocol to three other PrAMPs: apidaecin‐1b, pyrrhocoricin, and bactenecin 7(1–16) and found that the substitutions (R4K and I8K/R) for apidaecin‐1b improve the activity by twofold (p < .05) against nonpathogenic Escherichia coli. Moreover, the substitutions (L7K/R and R14K) for pyrrhocoricin improve the activity by 2–10‐fold (p < .05) against some strains of E. coli and Salmonella Typhimurium. We also performed activity tests against inner membrane protein (SbmA or YgdD) knockout strains. The result is consistent with previous studies that SbmA is the major transporter for apidaecin‐1b and pyrrhocoricin derivatives. However, bactenecin 7(1–16) functions independently of these transporters. In addition, several apidaecin‐1b derivatives exhibit enhanced activity relative to wild‐type only in the absence of SbmA, which is consistent with mutations that enhance transport across the inner membrane. A high performance liquid chromatography‐based kinetic assay for cellular association and internalization demonstrates that the selected cationic mutations can improve cellular association in minimal media, but this enhanced association is not required for increased activity, which suggests the importance of inner membrane transport. These functional studies on cationic mutants of PrAMPs advance understanding of potency and mechanism and advance the ability to engineer improved antimicrobials as evidenced by the identification of the pyrrhocoricin mutant (L7R and R14K) with 10‐fold elevated potency against pathogenic E. coli.
A simplified techno‐economic model for the molecular pharming of antibodies
Authors: Mir‐Artigues Pere , Twyman Richard M. , Alvarez Derry , Cerda Bennasser Pedro , Balcells Merce , Christou Paul , Capell Teresa 
Published: June 2019

AbstractBy the end of 2017, the Food and Drug Administration had approved a total of 77 therapeutic monoclonal antibodies (mAbs), most of which are still manufactured today. Furthermore, global sales of mAbs topped $90 billion in 2017 and are projected to reach $125 billion by 2020. The mAbs approved for human therapy are mostly produced using Chinese hamster ovary (CHO) cells, which require expensive infrastructure for production and purification. Molecular pharming in plants is an alternative approach with the benefits of lower costs, greater scalability, and intrinsic safety. For some platforms, the production cycle is also much quicker. But do these advantages really stack up in economic terms? Earlier techno‐economic evaluations have focused on specific platforms or processes and have used different methods, making direct comparisons challenging and the overall benefits of molecular pharming difficult to gauge. Here, we present a simplified techno‐economic model for the manufacturing of mAbs, which can be applied to any production platform by focusing on the most important factors that determine the efficiency and cost of bulk drug manufacturing. This model develops economic concepts to identify variables that can be used to achieve cost savings by simultaneously modeling the dynamic costs of upstream production at different scales and the corresponding downstream processing costs for different manufacturing modes (sequential, serial, and continuous). The use of simplified models will help to achieve meaningful comparisons between diverse manufacturing technologies.
To whom and when to give: Effects of intimacy and obligation on expressive motives, gift choice, and information search in gift giving
Authors: Kim Namin , Kim Sukho 
Published: June 2019

AbstractWhen consumers purchase gifts for others, their behaviors are different from those when they buy something for themselves. The present study aims to understand the entire gift purchase process including perception of the recipient and occasion, formation of motives, gift type choices, and information search. For this purpose, an expressive motive (motive to express the relationship or givers' self through a gift) was introduced and hypotheses were developed on how perceived intimacy and obligation influence expressive motives and how these motives affect consumers' choice of gift types (hedonic vs. utilitarian) and information search modes (online vs. offline). A memory‐based survey involving a student sample (n = 355) was conducted, and three major findings were revealed. First, more intimacy and less obligation increased expressive motives. Second, expressive motives influenced the giver's choice of a gift type. More specifically, givers with high expressive motives tended to choose a gift with a high level of hedonic quality and a low level of utilitarian quality. Finally, gift types that givers intended to purchase influenced information search. Givers searched for information online more when they purchased gifts with high utilitarian quality whereas they searched for offline information more when they purchased gifts with high hedonic quality. Results have practical implications for manufacturers and retailers whose businesses involve gifts.
Interrogating the Surface Intermediates and Water Oxidation Products of Boron‐Doped Diamond Electrodes with Scanning Electrochemical Microscopy
Authors: Counihan Michael J. , Setwipatanachai Worapol , Rodríguez‐López Joaquín 
Published: June 2019

AbstractBoron‐doped diamond (BDD) electrodes are widely used in electrochemical sensing and water purification owing to their chemical and structural stability under harsh reaction conditions. Water oxidation at BDD electrodes is known to produce reactive oxygen species, but the discharged and surface chemistries involved in these processes have not been studied in depth. Here, we present scanning electrochemical microscopy (SECM) studies of electrogenerated intermediates and products formed on sp2 carbon‐containing BDD electrodes that display stark differences in their reactivity as a function of electrolyte type and pH during water oxidation. The most reactive and abundant species discharged from the electrode were observed at pH 11 in sulfate electrolyte. With the surface interrogation mode of SECM, two kinetically distinct surface intermediates were clearly distinguished, with one forming two orders of magnitude faster than the other but displaying a slower desorption rate. The surface coverage of these species was estimated in the range of 4–7×10−5 mol/cm2 for the first, and 3–4.4×10−5 mol/cm2 for the second one. SECM imaging suggested that regions of increased product evolution have decreased electron transfer kinetics and limited surface sites for intermediate binding. This work establishes methods for studying highly reactive intermediates found in BDD and paves the way for the inspection of other interfaces where solvolysis impacts their reactivity and evolution.
Triarylborane‐Based Helical Donor–Acceptor Compounds: Synthesis, Photophysical, and Electronic Properties
Authors: Jia Xiangqing , Nitsch Jörn , Ji Lei , Wu Zhu , Friedrich Alexandra , Kerner Florian , Moos Michael , Lambert Christoph , Marder Todd B. 
Published: June 2019

AbstractThe synthesis and characterization of 10‐(dimesitylboryl)‐N,N‐di‐p‐tolylbenzo[c]phenanthren‐4‐amine (3‐B(Mes)2‐[4]helix‐9‐N(p‐Tol)2 1) and 13‐(dimesitylboryl)‐N,N‐di‐p‐tolyldibenzo[c,g]phenanthren‐8‐amine (3‐B(Mes)2‐[5]helix‐12‐N(p‐Tol)2 2) are reported herein. Their electrochemical and photophysical properties have been studied experimentally and theoretically. The donor and acceptor‐substituted helicene derivatives exhibit moderate fluorescence quantum yields in THF (Φf=0.48 and 0.61 for 1 and 2, respectively), which are higher than unsubstituted ones (Φf=0.18 for [4]helicene; Φf<0.05 for [n]helicenes (n≥5)). In the solid state, the Φf values are higher (Φf=1.00 and 0.55 for 1 and 2, respectively) than those in solution, most likely due to the restrictions of molecular motions. The S1←S0 transitions of 1 and 2 are predominately HOMO→LUMO transitions. Upon excitation with UV light, the interplanar angle between the two terminal aryl rings of the [5]helix core of 2 decreases (S1 state compared with S0 state), which is similar to placing a spring under an external force.
Catalytic Enantioselective Protonation of Monofluorinated Silyl Enol Ethers towards Chiral α‐Fluoroketones
Authors: Liao Kui , Hu Xiao‐Si , Zhu Ren‐Yi , Rao Ruo‐Han , Yu Jin‐Sheng , Zhou Feng , Zhou Jian 
Published: June 2019

Summary of main observation and conclusionDescribed herein is an organocatalytic enantioselective protonation of monofluorinated silyl enol ethers, affording an array of optically active α‐secondary α‐fluoroketones in good to high yields and enantioselectivities, under the catalysis of bifunctional cinchonidine derived squaramide C4. It represents a rare example of facile synthesis of enantioenriched α‐secondary α‐fluoroketones. With D2O as the deuterium source and MeOD as the solvent, the first highly enantioselective preparation of chiral α‐deuterated α‐fluoroketones in >92% deuteration is developed.
Rational Design of Efficient Organic Phototherapeutic Agents via Perturbation Theory for Enhancing Anticancer Therapeutics
Authors: Xu Yunjian , Zhao Menglong , Wu Licai , Li Feiyang , Li Mingdang , Xie Mingjuan , Liu Shujuan , Huang Wei , Zhao Qiang 
Published: June 2019

AbstractThe development of efficient phototherapeutic agents (PTA) through rational and specific principles exhibits great potential to the biomedical field. In this study, a facile and rational strategy was used to design PTA through perturbation theory. According to the theory, both the intersystem crossing rate for singlet oxygen generation and nonradiative transition for photothermal conversion efficiency can be simultaneously enhanced by the rational optimization of donor–acceptor groups, heavy atom number, and their functional positions, which can effectively decrease the energy gap between the singlet and triplet states and increase the spin‐orbit coupling constant. Finally, efficient PTA were obtained that showed excellent performance in multimode‐imaging‐guided synergetic photodynamic/photothermal therapy. This study therefore expands the intrinsic mechanism of organic PTA and should help guide the rational design of future organic PTA via perturbation theory.
Mechanoenzymatic Breakdown of Chitinous Material to N‐Acetylglucosamine: The Benefits of a Solventless Environment
Authors: Therien J. P. Daniel , Hammerer Fabien , Friščić Tomislav , Auclair Karine 
Published: June 2019

AbstractChitin is not only the most abundant nitrogen‐containing biopolymer on the planet, but also a renewable feedstock that is often treated as a waste. Current chemical methods to break down chitin typically employ harsh conditions, large volumes of solvent, and generate a mixture of products. Although enzymatic methods have been reported, they require a harsh chemical pretreatment of the chitinous substrate and rely on dilute solution conditions that are remote from the natural environment of microbial chitinase enzymes, which typically consists of surfaces exposed to air and moisture. We report an innovative and efficient mechanoenzymatic method to hydrolyze chitin to the N‐acetylglucosamine monomer by using chitinases under the recently developed reactive aging (RAging) methodology, based on repeating cycles of brief ball‐milling followed by aging, in the absence of bulk solvent. Our results demonstrate that the activity of chitinases increases several times by switching from traditional solution‐based conditions of enzymatic catalysis to solventless RAging, which operates on moist solid substrates. Importantly, RAging is also highly efficient for the production of N‐acetylglucosamine directly from shrimp and crab shell biomass without any other processing except for a gentle wash with aqueous acetic acid.
Ultrasound characteristics of thyroid nodules facilitate interpretation of the malignant risk of Bethesda system III/IV thyroid nodules and inform therapeutic schedule
Authors: Li Fu , Pan Denghua , Wu Yuquan , Peng Jinbo , Li Qing , Gui Xiaolong , Ma Wei , Yang Hong , He Yun , Chen Junqiang 
Published: June 2019

AbstractBackgroundThis study was designed to explore whether ultrasound of thyroid nodules facilitates the interpretation of the malignant risk of Bethesda III/IV thyroid nodules to inform further therapies.MethodsWe reviewed patient records in which the results of ultrasound‐guided fine‐needle aspiration (US‐FNA) were classified by the Bethesda III/IV in our institution between January 2016 and June 2018. Studies were retrieved from PubMed, Cochrane Central Register of Controlled Trials, ISI Web of Science, Science Direct, Wiley Online Library, EMBASE, China National Knowledge Infrastructure, WanFang, and Chinese VIP. The odds ratio (OR) was used to measure associations between risk factors and thyroid nodule malignancy.ResultsFifty‐nine cases of Bethesda III/IV with corresponding surgeries were included, and the malignancy risk was 54.2%. Meta‐analysis revealed irregular borders, solitary nodules, hypoechogenicity, microcalcifications, and being taller than wide, all of which increased the malignancy risk of thyroid nodules. Combined ORs for these factors were 4.08 (95% CI: 2.34‐7.14, P < .001), 2.18 (95% CI: 1.39‐3.42, P = .001), 2.02 (95% CI: 1.35‐3.01, P = .001), 3.21 (95% CI: 2.26‐4.56, P < .001), and 4.35 (95% CI: 3.07‐6.15, P < .001), respectively.ConclusionAs the risk of malignancy for papillary thyroid carcinoma (PTC) is high, when any one of the five ultrasound features of malignancy were confirmed, repeated FNA is recommended to confirm PTC‐type malignancy, even though nodules were Bethesda III/IV classification. However, repeated FNA should be avoided when none of these ultrasound features are identified because repeated FNA does not contribute to identifying non‐PTC type malignancies, such as follicular thyroid carcinoma and poorly differentiated thyroid carcinoma.
Supercritical flows overspilling from bypass‐dominated submarine channels and the development of overbank bedforms
Authors: McArthur Adam , Kane Ian , Bozetti Guilherme , Hansen Larissa , Kneller Benjamin C. 
Published: June 2019

AbstractOverbank deposits of submarine channels are typically thin‐bedded, fine‐grained and predominantly characterized by a series of sedimentary structures interpreted to record a relatively simple history of waning flow. Here, a new type of bedform indicative of Froude‐supercritical flow is reported from successions of thin‐bedded turbidites interpreted as channel overbank deposits in the Upper Cretaceous Rosario Formation, Baja California, Mexico. A link is demonstrated between the development of overbank deposits in the form of depositional terraces or internal levees and contemporaneously active sediment transport, bypass and deposition of coarser‐grained material in a channel. The overbank bedforms overlie an erosion surface and contain a suite of sedimentary structures indicative of initially Froude‐supercritical flow conditions and a progressive waning of flow strength. In some cases, a stacked repetition of facies is interpreted to record a rejuvenation of flow energy. The characteristic sedimentary sequence observed is as follows: (a) long wavelength, low amplitude erosional surface with superimposed scours; (b) antidune backsets; (c) upper stage plane‐parallel lamination; (d) subcritical climbing ripples; (e) supercritical climbing ripples; (f) lower stage planar laminated tops; (g) a sharp upper surface. The exact vertical sequence of sedimentary structures encountered varies depending on the point of observation with respect to the bedform crest and distance from the parent channel. The recognition of these distinctive bedforms allows for interpretation of sediment bypass and proximity to a channel thalweg. These bedforms have not hitherto been described and provide a further example of the range of flow processes operating in submarine channel–levee systems, which aids depositional environment interpretation in both subsurface and outcrop studies.
How much do we really lose?—Yield losses in the proximity of natural landscape elements in agricultural landscapes
Authors: Raatz Larissa , Bacchi Nina , Pirhofer Walzl Karin , Glemnitz Michael , Müller Marina E. H. , Joshi Jasmin , Scherber Christoph 
Published: June 2019

AbstractNatural landscape elements (NLEs) in agricultural landscapes contribute to biodiversity and ecosystem services, but are also regarded as an obstacle for large‐scale agricultural production. However, the effects of NLEs on crop yield have rarely been measured. Here, we investigated how different bordering structures, such as agricultural roads, field‐to‐field borders, forests, hedgerows, and kettle holes, influence agricultural yields. We hypothesized that (a) yield values at field borders differ from mid‐field yields and that (b) the extent of this change in yields depends on the bordering structure.We measured winter wheat yields along transects with log‐scaled distances from the border into the agricultural field within two intensively managed agricultural landscapes in Germany (2014 near Göttingen, and 2015–2017 in the Uckermark).We observed a yield loss adjacent to every investigated bordering structure of 11%–38% in comparison with mid‐field yields. However, depending on the bordering structure, this yield loss disappeared at different distances. While the proximity of kettle holes did not affect yields more than neighboring agricultural fields, woody landscape elements had strong effects on winter wheat yields. Notably, 95% of mid‐field yields could already be reached at a distance of 11.3 m from a kettle hole and at a distance of 17.8 m from hedgerows as well as forest borders.Our findings suggest that yield losses are especially relevant directly adjacent to woody landscape elements, but not adjacent to in‐field water bodies. This highlights the potential to simultaneously counteract yield losses close to the field border and enhance biodiversity by combining different NLEs in agricultural landscapes such as creating strips of extensive grassland vegetation between woody landscape elements and agricultural fields. In conclusion, our results can be used to quantify ecocompensations to find optimal solutions for the delivery of productive and regulative ecosystem services in heterogeneous agricultural landscapes.