bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and internal validation of a predictive model of cognitive decline 36 months following elective surgery
Authors: Jones Richard N. , Tommet Douglas , Steingrimsson Jon , Racine Annie M. , Fong Tamara G. , Gou Yun , Hshieh Tammy T. , Metzger Eran D. , Schmitt Eva M. , Tabloski Patricia A. , Travison Thomas G. , Vasunilashorn Sarinnapha M. , Abdeen Ayesha , Earp Brandon , Kunze Lisa , Lange Jeffrey , Vlassakov Kamen , Dickerson Bradford C. , Marcantonio Edward R. , Inouye Sharon K. 
Published: May 2021

AbstractIntroductionOur goal was to determine if features of surgical patients, easily obtained from the medical chart or brief interview, could be used to predict those likely to experience more rapid cognitive decline following surgery.MethodsWe analyzed data from an observational study of 560 older adults (≥70 years) without dementia undergoing major elective non‐cardiac surgery. Cognitive decline was measured using change in a global composite over 2 to 36 months following surgery. Predictive features were identified as variables readily obtained from chart review or a brief patient assessment. We developed predictive models for cognitive decline (slope) and predicting dichotomized cognitive decline at a clinically determined cut.ResultsIn a hold‐out testing set, the regularized regression predictive model achieved a root mean squared error (RMSE) of 0.146 and a model r‐square (R2) of .31. Prediction of “rapid” decliners as a group achieved an area under the curve (AUC) of .75.ConclusionSome of our models could predict persons with increased risk for accelerated cognitive decline with greater accuracy than relying upon chance, and this result might be useful for stratification of surgical patients for inclusion in future clinical trials.
Cryptococcus neoformans in a child with CSF rhinorrhoea: A cytopathological diagnosis
Authors: Sinha Pallavi , Singh Meeta , Sagar Tanu , Meher Ravi , Kumar Jyoti 
Published: May 2021

AbstractCryptococcosis is caused by Cryptococcus neoformans and is fatal in children. The fungus is known to enter respiratory tract by inhalation and localizes in lungs in immunocompetent host. Patients with immunocompromised state facilitate dissemination of disease. However, disseminated cases have been described in immunocompetent HIV‐negative individuals. CSF rhinorrhoea as a predisposing cause of cryptococcal meningitis has been rarely reported. We hereby describe C. neoformans directly spreading to the meninges in 1 year child due to CSF rhinorrhoea and the fungus was detected on fluid cytology.
Presence of the ketamine analog of 2‐fluorodeschloroketamine residues in wastewater
Authors: Shao Xue‐Ting , Yu Han , Lin Jian‐Guo , Kong Xiang‐Peng , Wang Zhuang , Wang De‐Gao 
Published: May 2021

AbstractKetamine (KET) analogs are increasingly emerging as new psychoactive substances (NPS). The present report describes the first detection of the KET analog, 2‐fluorodeschloroketamine (2F‐DCK), in influent samples collected from nine wastewater treatment plants in seven major Chinese cities from 2018 to 2020 by wastewater‐based epidemiology (WBE). An analytical method based on solid‐phase extraction and subsequent gas chromatography–mass spectrometry was developed for the detection of 2F‐DCK and KET. The stability experiments showed that 2F‐DCK and KET remained stable in wastewater for 15 days at room and frozen temperatures, and at two pH values (pH = 7 and pH = 2), with residue amounts between 90% and 110%. KET was detected in all samples, whereas 2F‐DCK was detected in only four samples: from Guangzhou in 2018, Shenzhen in 2019, and Quanzhou and Nanning in 2020, indicating that 2F‐DCK has been used as early as 2018 in China. The renal clearance of 2F‐DCK was predicted based on the quantitative structure–pharmacokinetic relationship model, which was used to calculate an excretion factor of 3.7. The 2F‐DCK consumption in four cities ranged from 3.71 ± 0.05 to 55 ± 0.09 mg/day/1000 inh, and KET ranged from 1.3 ± 0.04 to 76.5 ± 4.63 mg/day/1000 inh. This is the first study to investigate 2F‐DCK by WBE, which provides relevant real‐time data on the growth of NPS use, as well as useful information for the government to develop new policies.
Separating the wheat from the chaff: Observations on the analysis of lysergamides LSD, MIPLA, and LAMPA
Authors: Brandt Simon D. , Kavanagh Pierce V. , Westphal Folker , Stratford Alexander , Blanckaert Peter , Dowling Geraldine , Grill Matthias , Schwelm Hannes M. , Auwärter Volker , Chapman Stephen J. 
Published: May 2021

AbstractLysergic acid diethylamide (LSD) is a potent psychoactive substance that has attracted great interest in clinical research. As the pharmacological exploration of LSD analogs continues to grow, some of those analogs have appeared on the street market. Given that LSD analogs are uncontrolled in many jurisdictions, it is important that these analogs be differentiated from LSD. This report presents the analysis of blotters found to contain the N‐methyl‐N‐isopropyl isomer of LSD (MIPLA), and techniques to differentiate it from LSD and the N‐methyl‐N‐propyl isomer (LAMPA) under routine conditions. Gas chromatography (GC)‐solid phase infrared spectroscopy was particularly helpful. GC‐electron ionization‐tandem mass spectrometry of the m/z 72 iminium ion also provided sufficient information to distinguish the three isomers on mass spectral grounds alone, where chromatographic separation proved challenging. Derivatization with 2,2,2‐trifluoro‐N,N‐bis (trimethylsilyl)acetamide (BSTFA) also led to improved GC separation. Liquid chromatography single quadrupole mass spectrometry (LC‐Q‐MS) and in‐source collision‐induced dissociation allowed for the differentiation between MIPLA and LAMPA based on distinct m/z 239 ion ratios when co‐eluting. An alternative LC‐MS/MS method improved the separation between all three lysergamides, but LSD was found to co‐elute with iso‐LSD. However, a comparison of ion ratios recorded for transitions at m/z 324.2 > 223.2 and m/z 324.2 > 208.2 facilitated their differentiation. The analysis of two blotters by LC‐Q‐MS revealed the presence of 180 and 186 μg MIPLA per blotter. These procedures may be used to avoid inadvertent misidentification of MIPLA or LAMPA as LSD.
Autumn larval cold tolerance does not predict the northern range limit of a widespread butterfly species
Authors: Tremblay Philippe , MacMillan Heath A. , Kharouba Heather M. 
Published: May 2021

AbstractClimate change is driving range shifts, and a lack of cold tolerance is hypothesized to constrain insect range expansion at poleward latitudes. However, few, if any, studies have tested this hypothesis during autumn when organisms are subjected to sporadic low‐temperature exposure but may not have become cold‐tolerant yet. In this study, we integrated organismal thermal tolerance measures into species distribution models for larvae of the Giant Swallowtail butterfly, Papilio cresphontes (Lepidoptera: Papilionidae), living at the northern edge of its actively expanding range. Cold hardiness of field‐collected larvae was determined using three common metrics of cold‐induced physiological thresholds: the supercooling point, critical thermal minimum, and survival following cold exposure. P. cresphontes larvae were determined to be tolerant of chilling but generally die at temperatures below their SCP, suggesting they are chill‐tolerant or modestly freeze‐avoidant. Using this information, we examined the importance of low temperatures at a broad scale, by comparing species distribution models of P. cresphontes based only on environmental data derived from other sources to models that also included the cold tolerance parameters generated experimentally. Our modeling revealed that growing degree‐days and precipitation best predicted the distribution of P. cresphontes, while the cold tolerance variables did not explain much variation in habitat suitability. As such, the modeling results were consistent with our experimental results: Low temperatures in autumn are unlikely to limit the distribution of P. cresphontes. Understanding the factors that limit species distributions is key to predicting how climate change will drive species range shifts.
Detection of prey DNA in bat feces: Effects of time since feeding, meal size, and prey identity
Authors: Schattanek Petra , Riccabona Sophie Anna , Rennstam Rubbmark Oskar , Traugott Michael 
Published: May 2021

AbstractMolecular analyses of feces are widely used to study the feeding ecology of bats. However, little is known about how detectability of prey DNA from bat feces is influenced by gut retention time, mass of prey eaten, or prey identity, which hampers the interpretation of field data. Here, we address these knowledge gaps by conducting a feeding experiment in which different insect species and meal sizes were offered to two bat species, Myotis daubentonii and Pipistrellus nathusii. The feeding regime consisted of three main and three side prey species fed in different masses, whereupon feces were collected over 72 h and examined for prey DNA using a species‐specific multiplex PCR system. DNA of all three main prey species was detectable from feces produced within 1 h after consumption of a meal. Prey detectability decreased over the following 10–20 h, and after 40 h only spurious detections occurred. For both prey and bats, species identity affected detectability: for example, mealworms were detected for a longer time post‐feeding compared to wax moths/house flies, and the latter were detected for a shorter time in M. daubentonii than in P. nathusii. While DNA from all three side prey species was detectable, signals were weak and detections limited to the first 20 h after consumption. These findings indicate that detectability of prey DNA from bat feces is foremost affected by the mass of prey consumed and time post‐feeding, whereas it does not strongly differ between prey species. To increase the detection of prey ingested in low mass, we suggest collecting fecal samples soon after bats return from foraging, as detectability is highest right after feeding occurs, and detections largely depict the previous foraging bout (with detection windows usually <24 h).
Nanodelivery of the Gramicidin Peptide for Enhancing Antimicrobial Activity
Authors: Antezana Pablo E. , Municoy Sofia , Bellino Martín G. , Martini M. Florencia , Desimone Martín F. 
Published: May 2021

AbstractGramicidin S (GraS) is an amphiphilic peptide that has emerged as an effective alternative antibiotic. However, its applicability is restricted for clinical uses due to its effect on eukaryotic cells and low aqueous solubility. In this work, a novel water‐soluble peptide formulation with bactericidal activity is developed by the incorporation of Gramicidin S in the lipid bilayer of liposomes (L‐GraS). As a result, GraS included in the lipid vesicles is stabilized in aqueous medium and showed antimicrobial activity against Staphylococcus aureus. In addition, L‐GraS reveals enhanced biocompatibility with mammalian cells in comparison with the free peptide. Molecular dynamics simulations shed light on the collective behavior between GraS peptides and liposomes from a molecular approach. The molecular dynamic simulations are in agreement with experimental results and further confirm the effective incorporation of GraS in the liposomes, letting understand the best formulation procedure of the vesicles. Therefore, the L‐GraS nanosystem presented here is an interesting alternative to conventional antibiotics, with less restrictions and promising features to improve current therapies.Practical Applications: Incorporation of GraS in liposomes is an interesting approach to increase the solubility of the peptide, thus expanding its therapeutic horizon as a promising alternative to combat bacterial colonization especially in wound infections.
A simple, rapid, and robust “on‐the‐go” identity testing of biotherapeutics using FTIR spectroscopy
Authors: Afzal Mohammad A. , Bhojane Purva P. , Rathore Anurag S. 
Published: May 2021

AbstractThe stunning rise of biotherapeutics as successful treatments of complex and hard‐to‐treat diseases, in particular cancer, has necessitated the development of a rapid analytical method capable of differentiating these otherwise significantly similar antibody‐based products. The existing methods for product identification pose significant drawbacks in terms of the consumption of time and labor. Here, we present an FTIR spectroscopy‐based simple, rapid, and robust method that is capable of differentiating between the biotherapeutics (both innovator products and biosimilars). The proposed approach uses partial least‐squares‐discriminant analysis to pinpoint subtle differences in the FTIR spectra of the samples, enabling us to not only identify the product but also calculate its concentration. This FTIR‐based method can be used to fulfill the identity testing requirement of a pharmaceutical drug in its final packaged form set by the US Food and Drug Administration. Along with this, identity testing can also be deployed at multiple steps in the manufacturing process and can also be used by the appropriate regulatory or government agency for tackling counterfeits of biotherapeutic products.
The electrochemistry of ammonium dihydrogen phosphate, disodium phosphate, ammonium chloride on Mg‐based and polycrystalline Pt electrodes
Authors: Kékedy‐Nagy László , Abolhassani Mojtaba , Greenlee Lauren F. , Pollet Bruno G. 
Published: May 2021

AbstractIn this study, the electrochemical mechanisms of struvite formation were investigated by studying the behavior of Mg‐based and (poly)crystalline‐Pt electrodes in the presence of ammonium dihydrogen phosphate, disodium phosphate, and ammonium chloride solutions. It was found that a precipitate was formed on the Mg‐based electrodes, while the poly‐Pt electrode showed typical voltammetric features in aqueous electrolytes. The structure, morphology, and composition of the electrochemically obtained precipitates collected from the surface of the Mg‐based electrodes were analyzed by scanning electron microscopy (SEM), X‐ray diffraction (XRD), and X‐ray photoelectron spectroscopy (XPS). The results showed that the precipitate morphology was impacted by the composition of the electrolytes and the purity of the magnesium. Moreover, the Tafel kinetics and corrosion rates (vcorr) directly correlated with the electrolyte and the electrode material compositions, whereby both showed a general increase when the Mg‐based electrodes were employed in the presence of chloride anions. The Tafel slopes (β) obtained for the oxygen reduction reaction (ORR) with the poly‐Pt electrode showed a significant difference between the forward and reverse potential scans in the various electrolytes used, a finding which was mainly attributed to the adsorption of hydroxide species, alkali cations, and phosphate anions to the surface whereby these species blocked the ORR active sites.
Dynamics characteristics of geometrically nonlinear isolation systems for seismic protection of equipment
Authors: Hsu Ting‐Wei , Chang Chia‐Ming 
Published: May 2021

AbstractEarthquakes pose risks to sensitive equipment and may result in dramatic economic loss. A widely used control strategy is to install an isolation system underneath equipment; however, excessive isolation displacements may be induced during severe earthquakes. Viscous dampers are recommended to be placed along with the isolation layer and to reduce displacements. Indeed, this combination is designed for a certain earthquake level and may be less effective in other earthquake levels. In this study, an isolation system with viscous dampers, which is installed perpendicular to the motion direction at the equilibrium position, is proposed to enhance seismic performance of important equipment through this geometrically nonlinear configuration. This configuration provides a better reduction in absolute accelerations during small‐to‐moderate earthquakes, while isolation displacements can be effectively mitigated during severe earthquakes. To understand the dynamic characteristics of this system, a series of investigations are carried out. The features of the effective control force are explored by the effective damping, and the phase plane analysis is conducted to understand the isolation system behavior. Then, the averaging method is employed to obtain the frequency–amplitude relationship of the proposed system, and the results inform the frequency domain behavior. The geometrically nonlinear damping is experimentally explored. Control effectiveness of the proposed system is also evaluated under seismic excitation and compared with the conventional isolation system (i.e., viscous dampers installed parallel to the isolation motion direction). As a result, the viscous damper with geometric nonlinearity can be more adaptive to different earthquake levels and thereby improves seismic isolation performance.
Influence of a new‐bored neighbouring cavity on the seismic response of an existing tunnel under incident P‐ and SV‐waves
Authors: Zlatanović Elefterija , Šešov Vlatko , Lukić Dragan Č. , Bonić Zoran 
Published: May 2021

AbstractOne of the important problems regarding the tunnel design in seismically active areas is the assessment of the mutual effect of two closely running tunnels. With the propagation of seismic waves, the stresses in certain sections of a tunnel, owing to the presence of an adjacent tunnel, can exceed those occurring when considering the single‐tunnel case. In the focus of this study is the hitherto unexplored elastic wave diffraction problem, which considers the influence of the presence of a new‐bored neighbouring cavity on the seismic response of an existing tunnel, under incident P‐waves/SV‐waves. The wave function expansion method, the corresponding boundary conditions along the tunnel and cavity contours, and the translational addition theorem for bi‐cylindrical wave functions are jointly employed to develop an exact mathematical solution of the given problem in the form of infinite FourierBessel series, under the plane‐strain conditions. The dynamic effects of structures are presented in the form of a newly introduced dynamic stress alteration factor as a measure of the variation of dynamic hoop stress amplitudes in the lining and the surrounding medium of an existing tunnel affected by the presence of a closely running newly‐constructed tunnel opening. The results of this study are believed to be useful for interpretation of design rules, particularly considering that seismic standards for tunnels are still in the preliminary stage, where the aspect of the minimum seismically safe distance of a newly‐constructed tunnel opening in the vicinity of an existing tunnel should be of particular concern.
Experimental study on solar air heater with encapsulated phase change material on its absorber plate
Authors: Raju Gadi , Kumar Mandapati Mohan Jagadeesh 
Published: May 2021

AbstractEffective usage of solar air heaters (SAH) is limited to specific time due to nonavailability and low intensity of solar radiation. In addition, SAH suffers from lower thermal efficiencies. Encapsulated phase change material (PCM) on absorber plate of SAH is one of the passive techniques to improve thermal efficiency of SAH as well as to extend its application to nonsunshine hours. In this article, capsules of circular and square cross sections filled with PCM were used on absorber plate of a double pass counter flow SAH and SAH efficiency was experimentally determined. Capsules were placed in inline and staggered grid arrangements perpendicular to the flow direction of the air and paraffin wax was used as the PCM. Experiments were conducted each day in two cycles (charging PCM from 10:00 amto 2:00 pmand discharging PCM from 4:30 pmto 5:30 pm), with fixed mass flow rate of air in between 0.00879 and 0.01484 kg/s. It is found from the results that, efficiency of SAH with square staggered encapsules is at an average of 15.8% higher than the remaining arrangements. During PCM discharge, air temperature at the SAH exit was at an average of 5.17°C greater than ambient temperature for all arrangements.
Ameliorative impacts of Glycyrrhiza glabra root extract against nephrotoxicity induced by gentamicin in mice
Authors: Nassan Mohamed A. , Soliman Mohamed M. , Aldhahrani Adil , Althobaiti Fayez , Alkhedaide Adel Q. 
Published: May 2021

AbstractGentamicin is an effective antibiotic that has been used worldwide for many years. While considered an essential medicine by the WHO, gentamicin can also lead to severe kidney damage. This study explored the ameliorative effects of Glycyrrhiza glabra root extract on gentamicin‐induced renal injury in mice. Four groups of n = 7 mice were used: (a) control; (b) G. glabra‐only; (c) gentamicin‐only; and (d) gentamicin plus G. glabra. Kidney samples were tested for: antioxidant enzyme activity (superoxide dismutase [SOD] and glutathione peroxidase [Gpx]); expression of HO‐1 and nuclear factor erythroid 2‐related factor 2 genes; expression of Cox‐2 and Bax; cytokine levels (IL‐1β, and IL‐6); histopathological anomalies; and standard renal functional component levels (creatinine, urea, and blood urea nitrogen). The effects of gentamicin were generally reversed or normalized following treatment with G. glabra root extract. Gentamicin decreased Gpx and SOD parameters and increased IL‐1 β and IL‐6 levels, but these returned to normal in the G. glabra‐treated group. Gentamicin upregulated tissue levels of Cox‐2 and Bax, and downregulated HO‐1 and Nrf‐2 expression but again, and these levels returned to normal in the group treated with G. glabra. Mice that had received gentamicin exhibited acute renal blood vessel congestion, focal interstitial round cell aggregation, and hydropic degeneration of renal tubular epithelium. However, those that had also received G. glabra showed a normal histopathology. Findings from this study indicate that in mouse models, gentamicin‐induced kidney damage can be reversed or ameliorated by administering G. glabra, so it can be considered as an effective complimentary therapy.
A control approach for alternating current disturbance signal of fuel cells based on MOSFET high‐speed switch
Authors: Zhou Y. F. , Dong Q. C. , Huang L. J. , Li L. H. , Lian J. 
Published: May 2021

AbstractInternal resistance is currently one of the most effective ways to achieve the performance improvement, control optimization, and on‐line fault diagnosis of fuel cells. In the fuel cell internal resistance test (FCIRT) system (FCIRTS), the alternating current (AC) disturbance signal is mainly achieved through the use of DC/DC converters or other expensive program‐controlled equipments, which are expensive and large, and it is not conducive to the commercial application of low‐cost FCIRTS. In particular, for the fuel cell vehicles based on dual‐source motors, the DC/DC structure is cancelled. Therefore, a new method should be used in the FCIRTS. To solve this problem, a low‐cost fuel cell AC disturbance signal control approach based on MOSFET high‐speed switch was proposed in this paper. In the approach, a circuit model of MOSFET high‐speed regulation was built, and the AC control of the fuel cells was achieved finally by simulation analysis and experimental verification. The proposed approach can not only independently control the AC components, but also save the system space and cost because of reducing reliance on DC/DC converters and dedicated equipments. Therefore, it is of great value to the development of low‐cost, high‐precision, and real‐time FCIRTS.