bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Incidence of Extended-Spectrum Beta-Lactamase (ESBL)-Producing Bacteria in Salad Vegetables in Ondo City, Nigeria
Authors: Bello O. O. , Oni M. O. , Bello J. O. , Bello T. K. 
Published: May 2019

Aim: This study was carried out to determine the occurrence of extended-spectrum beta-lactamase (ESBL) producing bacteria in salad vegetables in Ondo City, Nigeria.
Study Design: An experimental study design with randomized sampling.
Place and Duration of the Study: The research was carried out in the Department of Biological Sciences of Wesley University, Ondo State, Nigeria.
Methodology: Samples of cucumber, carrot, green pea, green beans, sweet corn and cabbage were analysed on appropriate agar medium. Pure isolates were identified by biochemical tests and confirmation was done by the use of API 20 E and API 20 NE in accordance with standard procedures. ESBLs screening was carried out using the double disk synergy test. Data were statistically analyzed using MedCalc statistical software (version 17.2).
Results: Total viable bacterial counts (TVBCs) ranged from 1.1 × 103 to 7.1 x 105 cfu/ml; total coliform counts (TCC) ranged from 1.2 x 102 to 3.9 x 103 cfu/ml while total faecal counts (TFC) ranged from 0 to 2.9 × 102 cfu/ml. There were statistical differences in mean TVBCs of the samples (P < 0.05). The mean TCCs of cabbage, carrot and cucumber showed no statistical significance; green beans, green pea and sweet corn also showed no statistical significance (P > 0.05). One hundred and sixty (166) isolates obtained from the samples were identified as Bacillus cereus, Citrobacter freundii, Escherichia coli, Klebsiella pneumoniae, Morganella morganii, Pseudomonas aeruginosa, Proteus mirabilis, Staphylococcus aureus, Serratia marcesens and Staphylococcus saprophyticus. At least one member of all bacterial species, except S. saprophyticus, produced ESBL.
Conclusion: This study revealed that salad vegetables could be a vehicle for the spread of extended-spectrum beta-lactamase-producing bacteria which translates to a threat to public health around the world as salads are loved and consumed by all categories of people globally.
Diabetic Foot and Self-awareness of This Entity
Authors: Barranco-Cuevas Irma Aide , Bello-Mora Alexa Itaí , Reyes-Bello Juvencio , Jacinto-López Miguel Ángel , Montiel-Jarquín Álvaro José , González-López Akihiki Mizuki , Vázquez-Cruz Eduardo 
Published: May 2019

Aims: To determine the relationship between the diabetic foot stages and the self-awareness about self-care of the feet in patients attending first level medical facility.
Study Design: This is a descriptive, cross sectional study.
Place and Duration of Study: This study was conducted in Unit Number 57 of the Family Medicine in the Mexican Institute of Social Security in Puebla, Mexico between January and June of 2017.
Methodology: We included 360 patients whom we surveyed to correlate between the level of knowledge about self-care of the feet in diabetic patients and its stages. We used a questionnaire in which the variables included gender, age, level of education, occupation, marital status, number of years since they were diagnosed with diabetes mellitus type 2, stage of the diabetic foot and level of knowledge related to this entity. Descriptive statistics and X2 were used.
Results: We included 360 patients who met the inclusion criteria. Their average age was 55.75 years, the average number of years with the diagnosis of diabetes mellitus was 6.07. There was a significant statistic association between the level of knowledge and the stage of the diabetic foot P = .049 a value of P= .05 was considered statistically significant.
Conclusion: There is an association between the stage of the diabetic foot and the knowledge about the self-care of the feet among patients.
Microhole‐Arrayed PDMS with Controllable Wettability Gradient by One‐Step Femtosecond Laser Drilling for Ultrafast Underwater Bubble Unidirectional Self‐Transport
Authors: Chen Chao , Shi Lu‐An , Huang Zhouchen , Hu Yanlei , Wu Sizhu , Li Jiawen , Wu Dong , Chu Jiaru 
Published: May 2019

AbstractAchieving the unidirectional transportation of bubbles in the liquid phase is of great importance for solving both academic and industrial issues. Here, Janus (hydrophobic and superhydrophobic surfaces) microhole‐arrayed polydimethylsiloxane fabricated by one‐step femtosecond laser drilling for ultrafast underwater bubble unidirectional transportation is reported. In aqueous solution, bubbles selectively penetrate from an aerophilic side to a superaerophilic one in the direction of both buoyancy and antibuoyancy, but are blocked in a reverse direction. More importantly, the bubbles readily penetrate through this Janus system within 81 ms, which is two orders of magnitude shorter than that of a previous Janus one because the aerophilic surface of current Janus system is more favorable for capturing and transporting the bubble than the superaerophobic surface of Janus system. Additionally, this “diode” presents a switchable property, which is dependent on the laser exposure dosage. According to X‐ray photoelectron spectroscopy spectrum, the underlying mechanism is that the excessive laser exposure dosage is inclined to induce the graft of oxyhydryl group as the substitution of the original hydrocarbyl group. This work may provide an innovatory insight for designing advanced materials for ultrafast gas bubble directional transportation/collection in aqueous media, in addition to gas/liquid separation.
Spontane trans‐selektive Transferhydrierung von unpolaren B=B‐Doppelbindungen
Authors: Dömling Michael , Arrowsmith Merle , Schmidt Uwe , Werner Luis , Castro Abril C. , Jiménez‐Halla J. Oscar C. , Bertermann Rüdiger , Müssig Jonas , Prieschl Dominic , Braunschweig Holger 
Published: May 2019

AbstractDie Transferhydrierung von NHC‐stabilisierten Diborenen mit Dimethylamminboran verläuft mit hoher Selektivität zu trans‐1,2‐Dihydrodiboranen. DFT‐Rechnungen, unterstützt durch Kinetik‐ und Deuterierungsexperimente, lassen auf einen schrittweisen Reaktionsmechanismus schließen, bei dem zuerst das Proton und anschließend das Hydrid über ein μ‐Hydrodiboronium‐Dimethylaminoborat‐Ionenpaar als Zwischenstufe übertragen werden.
Latente Nukleophile in der Lewis‐Base‐katalysierten, enantioselektiven N‐Allylierung von N‐Heterozyklen
Authors: Zi You , Lange Markus , Schultz Constanze , Vilotijevic Ivan 
Published: May 2019

AbstractLatente Nukleophile sind Moleküle oder Verbindungen, die selbst nicht nukleophil sind, aber unter geeigneten Bedingungen eine stark nukleophile Spezies generieren. Derartige Verbindungen können die Anwendbarkeit von Lewis‐Base‐katalysierten Reaktionen drastisch erweitern. Wir berichten nun, dass N‐silylierte Pyrrole, Indole und Carbazole als ebensolche Nukleophile unter Einwirkung einer Lewis‐Base mit allylischen Fluoriden reagieren können. Die Reaktionen zeigen eine hohe Toleranz gegenüber funktionellen Gruppen und unter Anwendung von Cinchona‐Alkaloiden als Katalysator lassen sich die Produkte in enantiomerangereicherter Form herstellen.
Latent Nucleophiles in Lewis Base Catalyzed Enantioselective N‐Allylations of N‐Heterocycles
Authors: Zi You , Lange Markus , Schultz Constanze , Vilotijevic Ivan 
Published: May 2019

AbstractLatent nucleophiles are compounds that are themselves not nucleophilic but can produce a strong nucleophile when activated. Such nucleophiles can expand the scope of Lewis base catalyzed reactions. As a proof of concept, we report that N‐silyl pyrroles, indoles, and carbazoles serve as latent N‐centered nucleophiles in substitution reactions of allylic fluorides catalyzed by Lewis bases. The reactions feature broad scopes for both reaction partners, excellent regioselectivities, and produce enantioenriched N‐allyl pyrroles, indoles, and carbazoles when chiral cinchona alkaloid catalysts are used.
Synthetic Haptens and Monoclonal Antibodies to the Cyanotoxin Anatoxin‐a
Authors: Quiñones‐Reyes Guillermo , Agulló Consuelo , Mercader Josep V. , Abad‐Somovilla Antonio , Abad‐Fuentes Antonio 
Published: May 2019

AbstractEarly warning systems for monitoring toxic events may benefit from the availability of monoclonal antibodies enabling the sensitive and specific detection of anatoxin‐a, a cyanotoxin involved in numerous cases of animal poisoning resulting from toxic algal blooms in freshwaters. Through the synthesis of three functionalized derivatives of anatoxin‐a, we have succeeded in generating the first‐ever reported immunoreagents (bioconjugates and antibodies) suitable for the development of immunoanalytical approaches aimed at rapid and onsite detection of this harmful cyanotoxin.
Synthesis and fabrication of high‐potent antimicrobial polymeric ultrathin coatings
Authors: Nagaraja Akshatha , Puttaiahgowda Yashoda Malgar , Devadiga Dheeraj 
Published: May 2019

ABSTRACTThe development of antimicrobial coatings in various sectors is escalating nowadays. However, design, synthesis, and fabrication of simple antimicrobial polymer coatings with potent biocidal action against pathogenic microbes are necessary to emerge. The current article deals with fabrication of high efficient ultrathin coatings of synthesized polymer for controlling pathogenic bacteria and fungi. The article is intensified with simple synthesis, characterization, fabrication of ultrathin coatings and their antimicrobial studies. The polymer structure is elucidated by FTIR,1HNMR, and 13CNMR, and the thermal properties are explained by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The antimicrobial activity of a polymer and their ultrathin coatings against Escherichia coli, Staphylococcus aureus, tubercular‐variant Mycobacterium smegmatis, and Candida albicans are reported elaborately. The morphology of ultrathin coating and their interaction with microorganisms are studied using a scanning electron microscope and an atomic force microscope. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47893.
Investigation and improvement of the scorch behavior of silica‐filled solution styrene‐butadiene rubber compound
Authors: Wang Danling , Chen Sheng , Chen Li , Chen Boyu , Ren Fujun , Zhu Chenxi , Feng Jie 
Published: May 2019

ABSTRACTEffects of different silane coupling agents on scorch time of silica‐filled solution styrene‐butadiene rubber compounds were studied. The flocculation of silica at high temperature, which was characterized by rubber processing analyzer (RPA) and transmission electron microscope (TEM), has been proved to be an important factor affecting the scorch time of the compounds. In order to prolong the scorch time, the hybrid silane technology, that is, combining different silanes such as bis(triethoxysilypropyl)‐tetrasulfide (TESPT) and n‐octyltriethoxysilane (OTES) together, was developed to improve silica dispersion and suppress silica flocculation. The results showed that when the content of TESPT is fixed, the increase of OTES can effectively increase the scorch time due to the suppression of silica flocculation while not affecting the polymer crosslinking. This phenomenon is absent for the case where the OTES content is fixed, but the TESPT content is varied because the sulfur atoms in the TESPT molecules will also participate in the vulcanization process, leading to the decrease in scorch time. Through the present study, a connection between silica flocculation and scorch time has been built up, which is important for rubber composite processing. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47918.
Long time release of water soluble drug from hydrophilic nanofibrous material
Authors: Pan Nan , Qin Juanrong , Fan Yuwei , Li Zeke , Song Botao 
Published: May 2019

ABSTRACTIn this study, mesoporous silica nanoparticles (MSNs) were embedded into the hydrophilic poly(vinyl alcohol) (PVA) nanofibrous mats to achieve sustained release of water soluble drug from hydrophilic nanofibrous mats. MSNs were successfully prepared based on a sol–gel method. Water soluble drug naproxen sodium was then loaded into the mesopores of the MSNs, and different amounts of the drug‐loaded MSNs were further incorporated into the fibers by the electrospinning process. Morphology of the nanofibrous mats was investigated, and it was found that all the fibers exhibited fibrous structure. Interestingly, lots of protrusions could be observed from the scanning electron microscopy images with high magnification, and numbers of the protrusions increased with the increasing of loading ratios of the MSNs from 5 to 15%. In addition, the wetting behaviors of the nanofibrous mats were also measured, and the water contact angles of all the mats were measured to be 0°. Finally, the drug release results indicated that all the PVA/MSNs composite nanofibrous mats showed an obviously prolonged drug release. The optimal loading ratio of the MSNs in the nanofibers was 10% due to the slowest drug release rate. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47922.
CFD and kinetic‐based modeling to optimize the sparger design of a large‐scale photobioreactor for scaling up of biofuel production
Authors: Ali Haider , Solsvik Jannike , Wagner Jonathan L. , Zhang Dongda , Hellgardt Klaus , Park Cheol Woo 
Published: May 2019

AbstractMicroalgal biofuels have not yet achieved wide‐spread commercialization, partially as a result of the complexities involved with designing and scaling up of their biosystems. The sparger design of a pilot‐scale photobioreactor (120 L) was optimized to enable the scale‐up of biofuel production. An integrated model coupling computational fluid dynamics and microalgal biofuel synthesis kinetics was used to simulate the biomass growth and novel biofuel production (i.e., bisabolene) in the photobioreactor. Bisabolene production from Chlamydomonas reinhardtii mutant was used as an example to test the proposed model. To select the optimal sparger configuration, a rigorous procedure was followed by examining the effects of sparger design parameters (number and diameter of sparger holes and gas flow rates) on spatially averaged bubble volume fraction, light intensity, friction velocity, power input, biomass concentration, and bisabolene production. The optimized sparger design increases the final biomass concentration by 18%, thereby facilitating the scaling up of biofuel production.
Virus clearance validation across continuous capture chromatography
Authors: Angelo James , Chollangi Srinivas , Müller‐Späth Thomas , Jusyte Simona , Xu Xuankuo , Ghose Sanchayita , Li Zhengjian 
Published: May 2019

AbstractMulticolumn capture chromatography is gaining increased attention lately due to the significant economic and process advantages it offers compared with traditional batch mode chromatography. However, for wide adoption of this technology in clinical and commercial space, it requires scalable models for executing viral validation studies. In this study, viral validation studies were conducted under cGLP guidelines to assess retro‐ (X‐MuLV) and parvo‐virus (MVM) clearance across twin‐column continuous capture chromatography (CaptureSMB). A surrogate model was also developed using standard batch mode chromatography based on flow path modifications to mimic the loading strategy used in CaptureSMB. The results show that a steady state was achieved by the second cycle for both antibody binding and virus clearance and that the surrogate model using batch mode chromatography equipment provided impurity clearance that was comparable to that obtained during cyclical operation of CaptureSMB. Further, the log reduction values (LRVs) achieved during CaptureSMB were also comparable to the LRVs obtained using standard batch capture chromatography. This was expected since the mode of virus separation during protein A chromatography is primarily based on removal during the flow through and wash steps. Finally, this study also presents assessments on the resin cleaning strategy during continuous chromatography and how the duration of clean‐in‐place solution exposure impacts virus carryover.
Polycomb Repressive Complex 2: Modulator Development for Functional Regulation of a Multiprotein Complex by Using Structural Information
Authors: Tokodai Yasuaki , Yakushiji Fumika 
Published: May 2019

AbstractFunctional regulation of a protein complex is generally difficult because information of the target complex as a whole is limited. However, regulation of a protein complex is important for understanding complicated biological events in cells and therapeutic possibilities. This concept article introduces the potential for the functional regulation of a multiprotein complex, polycomb repressive complex 2 (PRC2), by developing chemical modulators. Functional regulatory mechanisms of PRC2 are described by using protein interaction information found through structural analyses. Subsequently, possibilities of novel chemical modulator development of PRC2 based on structural insights into the complex and related interactions are discussed.
Frustrated Interfaces Facilitate Dynamic Interactions between Native Client Proteins and Holdase Chaperones
Authors: He Lichun , Hiller Sebastian 
Published: May 2019

AbstractMolecular chaperones are crucial for cellular life to ensure that all proteins obtain their right fold and functionality. Many chaperones promiscuously bind a wide spectrum of client proteins, ranging from nascent to quasi‐native and native proteins. Several recent studies have investigated, at atomic resolution, how chaperones interact with native proteins. Native proteins feature a wide variety of structural conformations, and therefore, a given chaperone cannot accomplish full surface complementarity to all of its client proteins. This limitation is circumvented by the recognition of frustrated regions on the client protein surface by the chaperone. In this interaction mode, the chaperone forms a multitude of transient local interactions with some segments of the client, whereas other parts are transiently not in favorable interactions. A permanent rearrangement of the client conformation on the chaperone occurs. Reconfiguration on the chaperone surface also gives the client a chance to fold into its correct, minimally frustrated conformation.
Targeted Heating of Enzyme Systems Based on Photothermal Materials
Authors: Wang Xuerui , Ou Gang , Zhou Ke , Wang Xiangqing , Wang Licheng , Zhang Xiaoyan , Feng Yi , Bai Yunpeng , Wu Hui , Xu Zhiping , Ge Jun 
Published: May 2019

AbstractThis study demonstrates that the enzymatic reaction rate can be increased significantly by targeted heating of the microenvironment around the enzyme, while maintaining the reaction system at environmental temperature. Enzyme molecules are covalently attached to the surface of Fe3O4@reduced graphite oxide (rGO). Under visible‐light irradiation, the reaction rate catalyzed by the enzyme–Fe3O4@rGO system is clearly enhanced relative to that of the free enzyme and a mixture of free enzyme and Fe3O4@rGO. This local heating mechanism contributes to promotion of the enzymatic reactions of the targeted heating of the enzyme (THE) system, which has been validated by using different enzymes, including lipase, glucose oxidase, and organophosphorus hydrolase. These results indicate that targeted heating of the catalytic centers has the same effect on speeding up reactions as that of traditional heating methods, which treat the whole reaction system. As an example, it is shown that the THE system promotes the sensitivity of an enzyme screen‐printed electrode by 14 times at room temperature, which implies that the THE system can be advantageous in improving enzyme efficiency, especially if heating the entire system is impossible or could lead to degradation of substrates or damage of components, such as in vitro bioanalysis of frangible molecules or in vivo diagnosis.
Trifluoromethylated Proline Surrogates as Part of “Pro–Pro” Turn‐Inducing Templates
Authors: Gadais Charlène , Van holsbeeck Kevin , Moors Samuel L. C. , Buyst Dieter , Fehér Krisztina , Van Hecke Kristof , Tourwé Dirk , Brigaud Thierry , Martin Charlotte , De Proft Frank , Pytkowicz Julien , Martins José C. , Chaume Grégory , Ballet Steven 
Published: May 2019

AbstractProline is often found as a turn inducer in peptide or protein domains. Exploitation of its restricted conformational freedom led to the development of the d‐Pro‐l‐Pro (corresponding to (R)‐Pro–(S)‐Pro) segment as a “templating” unit, frequently used in the design of β‐hairpin peptidomimetics, in which conformational stability is, however, inherently linked to the cis–trans isomerization of the prolyl amide bonds. In this context, the stereoelectronic properties of the CF3 group can aid in conformational control. Herein, the impact of α‐trifluoromethylated proline analogues is examined for the design of enhanced β‐turn inducers. A theoretical conformational study permitted the dipeptide (R)‐Pro–(R)‐TfmOxa (TfmOxa: 2‐trifluoromethyloxazolidine‐2‐carboxylic acid) to be selected as a template with an increased trans–cis rotational energy barrier. NMR spectroscopic analysis of the Ac‐(R)‐Pro–(R)‐TfmOxa–(S)‐Val‐OtBu β‐turn model, obtained through an original synthetic pathway, validated the prevalence of a major trans–trans conformer and indicated the presence of an internal hydrogen bond. Altogether, it was shown that the (R)‐Pro–(R)‐TfmOxa template fulfilled all crucial β‐turn‐inducer criteria.
Palladium‐Catalyzed Tunable Carbonylative Synthesis of Enones and Benzofulvenes
Authors: Peng Jin‐Bao , Wu Fu‐Peng , Spannenberg Anke , Wu Xiao‐Feng 
Published: May 2019

AbstractA palladium‐catalyzed four‐component carbonylative coupling reaction involving aryl halides, internal alkynes, arylboronic acids, and CO has been developed for the first time. All‐carbon substituted α‐unsaturated ketones and benzofulvenes can be selectively obtained in a highly regio‐ and stereocontrolled manner. Using Cu(TFA)2 as the additive, a series of tetrasubstituted α‐unsaturated ketones were prepared in moderate to high yields. Using more acidic Lewis acid Cu(OTf)2 as the additive, multisubstituted benzofluvenes were synthesized in moderate yields. This efficient methodology involved the formation of three new C−C bonds, and provided a divergent method for the quick construction of multisubstituted α‐unsaturated ketones and benzofulvenes from easily available starting materials.