bluuebunny/crossref_metadata_2025 huggingface dataset:
Micro‐computed tomography analysis of enamel structure after different bleaching treatments
Authors: Yalcin Eda Didem , Surmelioglu Derya , Orhan Kaan
Published: June 2021

The aim of this investigation is to assess effect of three different bleaching techniques on structural integrity, mineral density and volume of enamel via micro‐computed tomography (micro‐CT) and examine color changes by CIELAB and CIEDE2000 formulas. Twenty‐four upper premolar teeth were randomly separated into three different groups (n = 8) (group 1, 35% hydrogen peroxide (HP) gel with Er,Cr:YSGG laser activation; group 2, 35% HP gel with diode laser activation; group 3, 35% HP gel with chemically activation). High‐resolution micro‐CT system (Bruker Skyscan 1275, Kontich, Belgium) was carried out to scan samples. Each tooth was scanned twice before‐after application of bleaching with same scanning parameters. Structural thickness, structural separation, fragmentation index, mineral density, and mineral volume of enamel were calculated for each region of interest (ROI). Color changes were measured with spectrophotometer and calculated with CIELAB and CIEDE2000 formulas. Data analysis was made with one‐way ANOVA with post‐hoc LSD. Micro‐CT analysis indicated that statistically significant differences were found in structural thickness, and separation, mineral density, and mineral volume of enamel for different ROIs before and after whitening for whole groups (P < .05). Significant differences were detected among inter‐groups for these parameters in different ROIs (P < .05). There was no significant difference among groups for color alterations (P > .05). All bleaching applications exhibited similar efficiency on the enamel surface. Nevertheless, bleaching process with Er,Cr:YSGG laser had less negative effects on enamel as it showed less change in enamel compared to other bleaching treatments. Micro‐CT analysis of histomorphometric parameters can be useful for further mineralization studies of dental hard tissues.
The Generalization Error of Random Features Regression: Precise Asymptotics and the Double Descent Curve
Authors: Mei Song , Montanari Andrea
Published: June 2021

Deep learning methods operate in regimes that defy the traditional statistical mindset. Neural network architectures often contain more parameters than training samples, and are so rich that they can interpolate the observed labels, even if the latter are replaced by pure noise. Despite their huge complexity, the same architectures achieve small generalization error on real data.

This phenomenon has been rationalized in terms of a so‐called ‘double descent’ curve. As the model complexity increases, the test error follows the usual U‐shaped curve at the beginning, first decreasing and then peaking around the interpolation threshold (when the model achieves vanishing training error). However, it descends again as model complexity exceeds this threshold. The global minimum of the test error is found above the interpolation threshold, often in the extreme overparametrization regime in which the number of parameters is much larger than the number of samples. Far from being a peculiar property of deep neural networks, elements of this behavior have been demonstrated in much simpler settings, including linear regression with random covariates.

In this paper we consider the problem of learning an unknown function over the ‐dimensional sphere , from i.i.d. samples , . We perform ridge regression on random features of the form , . This can be equivalently described as a two‐layer neural network with random first‐layer weights. We compute the precise asymptotics of the test error, in the limit with and fixed. This provides the first analytically tractable model that captures all the features of the double descent phenomenon without assuming ad hoc misspecification structures. In particular, above a critical value of the signal‐to‐noise ratio, minimum test error is achieved by extremely overparametrized interpolators, i.e., networks that have a number of parameters much larger than the sample size, and vanishing training error. © 2021 Wiley Periodicals LLC.
On‐Cell NMR Contributions to Membrane Receptor Binding Characterization
Authors: Höfurthner Theresa , Mateos Borja , Konrat Robert
Published: June 2021

NMR spectroscopy has matured into a powerful tool to characterize interactions between biological molecules at atomic resolution, most importantly even under near to native (physiological) conditions. The field of in‐cell NMR aims to study proteins and nucleic acids inside living cells. However, cells interrogate their environment and are continuously modulated by external stimuli. Cell signaling processes are often initialized by membrane receptors on the cell surface; therefore, characterizing their interactions at atomic resolution by NMR, hereafter referred as on‐cell NMR, can provide valuable mechanistic information. This review aims to summarize recent on‐cell NMR tools that give information about the binding site and the affinity of membrane receptors to their ligands together with potential applications to in vivo drug screening systems.
Evaluation of healing at molar extraction sites with ridge preservation using a non‐resorbable dense polytetrafluoroethylene membrane: A four‐arm cohort prospective study
Authors: Al Hugail Arwa M. , Mealey Brian L. , Walker Christopher , Al Harthi Shaimaa , Duong Mylinh , Noujeim Marcel , Lasho David J. , Prihoda Thomas J. , Huynh‐Ba Guy
Published: June 2021

Objectives

To examine ridge dimensional changes and histologic parameters of healing when ridge preservation (RP) was performed at molar sites using dense polytetrafluoroethylene (dPTFE) membrane alone, without a bone graft.

Material and Methods

Eighteen patients had molar extraction and RP using dPTFE membrane alone. Ridge dimensions were measured using two standardized cone beam computerized tomography (CBCT) scans taken within 72 h and 3 months following extraction. Following a 3‐month healing period, an implant osteotomy was prepared using a trephine drill and bone cores were collected for histological analysis. Four‐arm analyses were performed using data from three previously published study arms of the same research group.

Results

There was a significant change in the buccal ridge height between the four groups at all aspects of the socket. Alveolar ridge width reduction at 3 mm from crest for all aspects (mesial, midpoint, distal) of the socket showed statistically significant difference for dPTFE alone group compared to the other three groups. Percentage of vital bone formation (62.10%) was significantly greater in dPTFE alone group compared to the other groups.

Conclusions

RP using dPTFE membrane alone in molar sites with intact socket walls showed successful outcomes in maintaining ridge dimensions and in histologic wound healing.
A note on investigating co‐occurrence patterns and dynamics for many species, with imperfect detection and a log‐linear modeling parameterization
Authors: MacKenzie Darryl I. , Lombardi Jason V. , Tewes Michael E.
Published: June 2021

Patterns in, and the underlying dynamics of, species co‐occurrence is of interest in many ecological applications. Unaccounted for, imperfect detection of the species can lead to misleading inferences about the nature and magnitude of any interaction. A range of different parameterizations have been published that could be used with the same fundamental modeling framework that accounts for imperfect detection, although each parameterization has different advantages and disadvantages.

We propose a parameterization based on log‐linear modeling that does not require a species hierarchy to be defined (in terms of dominance) and enables a numerically robust approach for estimating covariate effects.

Conceptually, the parameterization is equivalent to using the presence of species in the current, or a previous, time period as predictor variables for the current occurrence of other species. This leads to natural, “symmetric,” interpretations of parameter estimates.

The parameterization can be applied to many species, in either a maximum likelihood or Bayesian estimation framework. We illustrate the method using camera‐trapping data collected on three mesocarnivore species in South Texas.
A Configurational Approach to Model Triglyceride Pure Component Properties
Authors: Seilert Julia , Flöter Eckhard
Published: June 2021

In this contribution, a new model to predict the thermodynamic properties, namely enthalpy of fusion (ΔHf) and melting temperature (Tm), of pure triglycerides (TAGs) is presented. Different contributions to these properties could be expressed by means of repetitive structural attributes deduced from molecular structures. Carefully formulated configurational and geometrical simplifications enabled to attribute physical meaning to most of the parameters. Overall, the number of adjustable parameters is successfully minimized to less than half compared to the well‐known model proposed by Wesdorp in “Liquid‐multiple solid phase equilibria in fats: theory and experiments” (1990). Comparing both models revealed that the new model surpasses the reference model considering desirable prediction quality, thermodynamical consistency, and the number of adjustable parameters.

Practical application: The successful description of the phase behavior of TAG mixtures is crucial to understand complex phenomena in fat‐based products. This objective is based on reliable predictions of pure component properties and non‐ideal mixing in liquid‐ and solid‐phases. The newly formulated model gives reliable descriptions of experimental data and predictions of unknown data of TAGs — both thermodynamically consistent. Those are of benefit as prerequisite for any meaningful effort to predict the solid‐liquid phase behavior of TAG mixtures as well as crystallization kinetics.
Michael Addition‐Elimination and [4+1] Annulation of Sulfonylphthalide with Hydroxychalcones for the Synthesis of Alkylidenephthalides and Indanediones
Authors: Satam Nishikant , Basu Pallabita , Pati Soumyaranjan , Namboothiri Irishi N. N.
Published: June 2021

A protocol for the stereoselective synthesis of alkylidenephthalides and indanediones has been developed through the reaction of o‐hydroxychalcones and their styrenyl analogues, respectively, with 3‐sulfonylphthalide. The mechanism for the former synthesis involves Michael addition‐E2 elimination sequence, while the latter involves a [4+1] Hauser‐Kraus annulation. The mechanistic studies reveal that the strategically positioned phenolic group plays a pivotal role in the observed reactivities. The alkylidenephthalides, which are latent 1,4‐dicarbonyl compounds, were further converted to triarylfurans under Paal‐Knorr conditions in good to excellent yields. This protocol unravels several key features such as substrate specific product formation, namely, alkylidenephthalides from chalcones, and indanediones from vinylogous chalcones in their reaction with 3‐sulfonylphthalide as well as the role of alkylidenephthalides as 1,4‐dicarbonyl surrogates in Paal‐Knorr furan synthesis.
An Intramolecular Iodine‐Catalyzed C(sp3)−H Oxidation as a Versatile Tool for the Synthesis of Tetrahydrofurans
Authors: Koch Vanessa , Bräse Stefan
Published: June 2021

The formation of ubiquitous occurring tetrahydrofuran patterns has been extensively investigated in the 1960s as it was one of the first examples of a non‐directed remote C−H activation. These approaches suffer from the use of toxic transition metals in overstoichiometric amounts. An attractive metal‐free solution for transforming carbon‐hydrogen bonds into carbon‐oxygen bonds lies in applying economically and ecologically favorable iodine reagents. The presented method involves an intertwined catalytic cycle of a radical chain reaction and an iodine(I/III) redox couple by selectively activating a remote C(sp3)−H bond under visible‐light irradiation. The reaction proceeds under mild reaction conditions, is operationally simple and tolerates many functional groups giving fast and easy access to different substituted tetrahydrofurans.
Pressure‐responsive AuNPs/Polyacrylamide Nanocomposite Hydrogel with Highly Stable and Tunable Electrochemiluminescence Performances
Authors: Xie Qunfang , Tao Yingzhou , Zhang Ying , Cui Haiyan , Lin Zhenyu
Published: June 2021

Synergistically taking the advantage of distinctive porous matrix, luminophore and functional nanoparticles, we prepared functional nanocomposite hydrogel combining the hydrophilic three‐dimensional network of hydrogels as matrix for the adsorption of luminophore, Ru(bpy)32+, and in situ grown gold nanoparticles (AuNPs) as the conductive. Interestingly, the designed nanocomposite hydrogel shows external pressure resposnsive properties, which precisely tune the distance between the AuNPs becomes shorter, resulting in a remarkable amplification of electrochemiluminescence (ECL) signals. Additionally, differing from the poor stability of conventional ECL, uniform dispersion of the Ru(bpy)32+ over nanocomposite hydrogel significantly enhanced the long term stability of ECL.
Efficient co‐production of propionic acid and succinic acid by Propionibacterium acidipropionici using membrane separation coupled technology
Authors: Li Xiaolian , Wei Liquan , Wang Ziqiang , Wang Yunshan , Su Zhiguo
Published: June 2021

To improve the fermentation efficiency of Propionibacterium acidipropionici, a semi‐continuous coupled fermentation process was established to achieve co‐production of propionic acid (PA) and succinic acid (SA). First, the optimal proportion of glucose (Glc) and glycerol (Gl) as a mixed carbon source was determined, and the feeding procedure of Gl was optimized to make more energy flow in the direction of product synthesis. Then, ZGD630 anion exchange resin was used for efficient adsorption of PA, thereby eliminating the feedback inhibition effect of PA. Finally, an efficient, coupled fermentation process of P. acidipropionici characterized by membrane separation and chromatography technology was developed. The concentrations of PA and SA reached 62.22 ± 2.32 and 20.45 ± 1.34 g L−1, with corresponding productivity of 0.43 and 0.14 g L−1 h−1, increased by 65.38% and 48.54%, respectively. Membrane separation coupled fermentation of PA and SA could significantly improve the process economics of P. acidipropionici, and has good prospects for industrial application.
Comparative studies of metal‐organic decomposed GaxCeyOz and CeO2 based functional MOS capacitor
Authors: Tan Kar Yeow , Megat Abdul Hedei Puteri Haslinda , Mohd Zabidi Ainita Rozati , Ahmad Farah Hayati , Abdul Shekkeer Kammutty Musliyarakath , Lau Khai Shenn , Lim Way Foong , Hassan Zainuriah , Quah Hock Jin
Published: June 2021

A comparison between metal‐organic decomposed GaxCeyOz and CeO2 passivation layers subjected to post‐deposition annealing at 800°C in oxygen ambient was presented. Mitigation in the formation of positively charged oxygen vacancies in GaxCeyOz layer was disclosed by the grazing incidence X‐ray diffraction characterization as well as the acquisition of a lower value of positive effective oxide charge (Qeff) than CeO2 layer. In addition, GaxCeyOz layer was able to sustain a higher electric breakdown field and a lower leakage current density due to the attainment of a lower interface trap density extracted using Terman's and high‐low methods, slow trap density, and Qeff when compared with CeO2 layer.
A milligram‐scale flame calorimeter pyrolyzer system used to emulate burning of nonthermally thin solid samples
Authors: De Beer Jacques A. , Raffan‐Montoya Fernando , Stoliarov Stanislav I.
Published: June 2021

A new Milligram‐scale Flame Calorimetry (MFC) pyrolyzer system was developed to approximate heating conditions experienced by material samples in gram‐scale tests, such as cone calorimetry. The main features of this pyrolyzer system are a miniature flat heating coil embedded into a platform supporting the sample crucible. The use of a constant power rather than a constant heating rate operation mode distinguished the new MFC from the other mg‐scale flammability test method—microscale combustion calorimetry (MCC). A series of tests was carried out using the new MFC, cone, and MCC on five synthetic polymers representing a wide range of flammability behavior. All methods produced similar solid residue yields. The MFC peak heat release rate (HRR) was found to correlate linearly with the cone peak HRR (R2 = 0.93). The MCC peak HRR did not exhibit a strong correlation with the corresponding cone data. The new MFC was found to produce heat of combustion (HOC) values nearly identical to those measured in cone calorimetry. The MCC had a tendency to produce higher heats of combustion. Both MFC and MCC measured sample ignition temperatures that showed some correlation with the square root of the time to ignition measured in a cone calorimeter. The MFC airborne particular yield was found to correlate well (linear R2 = 0.91) with the average specific extinction area measured in the cone tests. It was concluded that the newly designed MFC can deliver relatively accurate flammability measurements similar to cone calorimetry while using three orders of magnitude smaller samples.
Synthesis of [2.2]Paracyclophane‐Based Glycidic Amides Using Chiral Ammonium Ylides
Authors: Weinzierl David , Waser Mario
Published: June 2021

An ammonium ylide‐mediated stereoselective protocol for the synthesis of a series of novel [2.2]paracyclophane‐based epoxides starting from racemic 4‐formyl[2.2]paracyclophane has been developed. By using achiral ammonium salts as ylide precursors, the corresponding epoxide products were obtained in isolated yields up to 76 % and with diastereoselectivities up to d.r.=9 : 1. When carrying out the reaction with chiral ammonium salts instead, the products were accessible with e.r.>93.5 : 6.5 and d.r.>3 : 1, accompanied with a moderately enantioselective kinetic resolution of the racemic starting aldehyde (e.r.=75 : 25).
A Molecular Analogue of the C−H Activation Intermediate of the Silica‐Supported Ga(III) Single‐Site Propane Dehydrogenation Catalyst: Structure and XANES Signature
Authors: Rochlitz Lukas , Searles Keith , Nater Darryl F. , Docherty Scott R. , Gioffrè Domenico , Copéret Christophe
Published: June 2021

Propane dehydrogenation is an important field of research due to an increasing world‐wide demand of propene while classical production routes through naphtha cracking are in decline. In that context, silica‐supported Ga(III) sites, synthesized from surface organometallic chemistry principles, show high selectivity and stability in the propane dehydrogenation reaction. This performance is in significant contrast to the reported fast deactivation and lower selectivity of most Ga2O3 and CrO3 based materials. The Ga‐catalyzed propane dehydrogenation reaction is proposed to proceed through the formation of Ga alkyl intermediates for which it would be desirable to have detailed structural and spectroscopic information. Here, we prepare a consistent series of Ga(III) molecular complexes with varying numbers of alkyl and siloxide ligands; they are characterized by single crystal X‐Ray diffraction and X‐Ray Absorption Near Edge Structure analysis, which is known to be highly sensitive to the Ga coordination environment. We report in particular the structure and the spectroscopic signatures of [Ga(iPr)(OSi(OtBu)3)2(HOSi(OtBu)3)], a molecular mimic of the key proposed reaction intermediates in the Ga‐catalyzed PDH reaction.
Unobserved components with stochastic volatility: Simulation‐based estimation and signal extraction
Authors: Li Mengheng , Koopman Siem Jan
Published: June 2021

The unobserved components time series model with stochastic volatility has gained much interest in econometrics, especially for the purpose of modelling and forecasting inflation. We present a feasible simulated maximum likelihood method for parameter estimation from a classical perspective. The method can also be used for evaluating the marginal likelihood function in a Bayesian analysis. We show that our simulation‐based method is computationally feasible, for both univariate and multivariate models. We assess the performance of the method in a Monte Carlo study. In an empirical study, we analyse U.S. headline inflation using different univariate and multivariate model specifications.
P53 inhibitor pifithrin‐α inhibits ropivacaine‐induced neuronal apoptosis via the mitochondrial apoptosis pathway
Authors: Zeng Lian , Zhang Fuyu , Zhang Zhen , Xu Min , Xu Yang , Liu Ying , Xu Hongxia , Sun Xiaodong , Sang Ming , Luo Huiyu
Published: June 2021

The neurotoxicity of local anesthetics (LAs) has attracted more and more attention, However, they lack preventive and therapeutic measures. Many studies have shown that apoptosis plays an important role in the process of LA‐induced neurotoxicity. As an important signaling molecule to activate apoptosis, p53 has been proved to be involved in the neurotoxicity induced by LAs, but the mechanism is unclear. In this study, we explored the effect of pifithrin‐α (PFT‐α), a p53 inhibitor, on apoptosis by ropivacaine (Rop) in vivo and in vitro. Cell viability and apoptosis detected by CCK‐8 and a JC‐1 apoptosis detection kit, the changes of spinal cord structure observed after hematoxylin and eosin staining, apoptosis of the spinal cord measured by terminal deoxynucleotidyl transferase dUTP nick end labeling staining, behavioral assessment of the nerve Injury evaluated by the detection of sciatic nerve conduction velocity (SNCV) andmechanical withdrawal threshold (MWT), the expression of p53 and many apoptosis‐related genes included Bax, Bcl‐2, and caspase‐3 detected by quantitative real‐time polymerase chain reaction, Western blot analysis, immunofluorescence, and immunohistochemistry. Results showed that PC12 cell viability decreased because of Rop, but the pretreatment of PFT‐α could protect it. And PFT‐α reduced the injuries in the spinal cord by Rop included vacuoles or edema. The results of immunofluorescence and immunohistochemistry testing showed that PFT‐α inhibited the p53 protein upregulated by Rop. Apoptosis rate and many proapoptotic genes include p53, Bax, caspase‐3 messenger RNA, and proteins were increased by Rop, but PFT‐α could decrease it. In conclusion, PFT‐α inhibited cell apoptosis and spinal cord injuries induced by Rop.
Facile extraction and characterization of cellulose nanocrystals from agricultural waste sugarcane straw
Authors: Lu Shuyu , Ma Tao , Hu Xinna , Zhao Jing , Liao Xiaojun , Song Yi , Hu Xiaosong
Published: June 2021

BACKGROUND

Sugarcane straw is an available but largely ignored lignocellulosic biomass to obtain cellulose nanocrystals (CNCs) with highly crystalline, tunable surface chemistries and a wide‐ranging adaptability. Herein, we utilized sugarcane straw to obtain pure cellulose via purification processes, followed by subsequent preparation of CNCs via sulfuric acid hydrolysis. The properties of the purified fibers and obtained CNCs were assessed by their composition, morphology, chemical structure, crystallinity and thermal stability.

RESULTS

After the purification process, alkali‐treated fibers (ATFs) contained 886.33 ± 1.25 g kg−1 cellulose, and its morphological analysis revealed a smooth and slender fibrous structure. The CNCs obtained by treatment with 64 wt% sulfuric acid at 45 °C for 60 min were isolated in a yield of 21.8%, with a diameter and length of 6 to 10 nm and 160 to 200 nm, respectively. Moreover, crystallinity index of these CNCs reached 62.66%, and thermal stability underwent a two‐step degradation. Short‐term ultrasonication after hydrolysis was employed to enhance isolation of the CNC particles and improve the anionic charge with higher value −38.00 mV.

CONCLUSION

Overall, isolation and characterization results indicated the potential for CNCs preparation using sugarcane straw, in addition to offering a fundamental understanding of this material and indicating potential applications. © 2021 Society of Chemical Industry.
Perioperative Challenges in Patients Transplanted with Livers from Extreme Obese Donors
Authors: Valvi Deepa , Villagomez Diego , Shah Malay B. , Mei Xiaonan , Gupta Meera , Ancheta Alexandre , Marti Francesc , Desai Siddharth , Benrajab Karim , Gedaly Roberto
Published: June 2021

The combination of rising rates of obesity and the shortage of deceased donor livers have forced the consideration of marginal liver donors in terms of body mass index (BMI) for liver transplantation (LT). To date, there are still conflicting data on the impact of donor obesity on post‐LT outcomes. We analyzed all patients undergoing LT alone in the United States (US) from October 2005 through December 2019 using the United Network of Organ Sharing (UNOS) data set. We categorized donor BMI >40 kg/m2 as extremely obese (EO). Primary endpoints included 30‐day perioperative mortality and early graft loss (EGL) within 7 days. A subgroup analysis was performed for the EO donor group to assess how macrovesicular steatosis (MaS) >30% affects 30‐day mortality and EGL within 7 days. A total of 72,616 patients underwent LT during the study period. The 30‐day perioperative mortality was significantly higher in the EO donor group (P = 0.02). On multivariate analysis, recipients undergoing LT with EO donors had a 38% higher 30‐day mortality risk (odds ratio [OR], 1.38; 95% confidence interval [CI], 1.21‐1.69) and 53% increased risk of EGL (OR, 1.53; 95% CI, 1.22‐1.90). MaS >30% was independently associated with a 2‐fold increased risk of 30‐day mortality (P = 0.003) and 3.5‐fold increased risk of EGL within 7 days (P < 0.001). The impact of MaS >30% in EGL was 2‐fold for all patients transplanted during the study period compared with 3.5‐fold in the EO donor group. There is an increased risk of EGL and 30‐day perioperative mortality in recipients transplanted with EO donors. Future studies are warranted in morbid and super obese donors to assess the possible effect of obesity‐related proinflammatory factors in EGL.
Chemical isotope labeling for quantitative proteomics
Authors: Tian Xiaobo , Permentier Hjalmar P. , Bischoff Rainer
Published: June 2021

Advancements in liquid chromatography and mass spectrometry over the last decades have led to a significant development in mass spectrometry‐based proteome quantification approaches. An increasingly attractive strategy is multiplex isotope labeling, which significantly improves the accuracy, precision and throughput of quantitative proteomics in the data‐dependent acquisition mode. Isotope labeling‐based approaches can be classified into MS1‐based and MS2‐based quantification. In this review, we give an overview of approaches based on chemical isotope labeling and discuss their principles, benefits, and limitations with the goal to give insights into fundamental questions and provide a useful reference for choosing a method for quantitative proteomics. As a perspective, we discuss the current possibilities and limitations of multiplex, isotope labeling approaches for the data‐independent acquisition mode, which is increasing in popularity.
DiSpect: Displacement spectrum imaging of flow and tissue perfusion using spin‐labeling and stimulated echoes
Authors: Zhang Zhiyong , Karasan Ekin , Gopalan Karthik , Liu Chunlei , Lustig Michael
Published: June 2021

Purpose

We propose a new method, displacement spectrum (DiSpect) imaging, for probing in vivo complex tissue dynamics such as motion, flow, diffusion, and perfusion. Based on stimulated echoes and image phase, our flexible approach enables observations of the spin dynamics over short (milliseconds) to long (seconds) evolution times.

Methods

The DiSpect method is a Fourier‐encoded variant of displacement encoding with stimulated echoes, which encodes bulk displacement of spins that occurs between tagging and imaging in the image phase. However, this method fails to capture partial volume effects as well as blood flow. The DiSpect variant mitigates this by performing multiple scans with increasing displacement‐encoding steps. Fourier analysis can then resolve the multidimensional spectrum of displacements that spins exhibit over the mixing time. In addition, repeated imaging following tagging can capture dynamic displacement spectra with increasing mixing times.

Results

We demonstrate properties of DiSpect MRI using flow phantom experiments as well as in vivo brain scans. Specifically, the ability of DiSpect to perform retrospective vessel‐selective perfusion imaging at multiple mixing times is highlighted.

Conclusion

The DiSpect variant is a new tool in the arsenal of MRI techniques for probing complex tissue dynamics. The flexibility and the rich information it provides open the possibility of alternative ways to quantitatively measure numerous complex spin dynamics, such as flow and perfusion within a single exam.
A longitudinal study of educational needs among patients with inflammatory arthritis
Authors: Grønning Kjersti , Lim Siriwan , Bratås Ola
Published: June 2021

Introduction

Patient education is important in the follow‐up and disease management for patients with chronic inflammatory arthritis. Patients’ needs for education and information varies, and it is important that the education is tailored to the individual patient. Hence, the aim of this study is to investigate whether patients’ educational needs change over time, and which demographic, disease‐related or self‐management characteristics that are associated with patients’ educational needs.

Methods

The Mann–Whitney U‐test was used to study patients’ longitudinal educational needs and whether their needs change over time, while multivariable linear regression analyses were used to investigate associations between patients’ educational needs and demographic variables, disease‐related and self‐management characteristics.

Results

There were no changes in patients’ educational needs in the domains of managing pain, movement, feelings, arthritis process and treatment from health professionals during the study period of seven years. A small decrease in educational needs in the domains self‐help measures (p‐value 0.047) and support from others (p‐value 0.010) was detected. The regression analyses showed that higher educational needs were associated with being female, lower educational level, shorter disease duration, and a lower level of patient activation.

Conclusions

Patients with chronic inflammatory arthritis have continual needs for patient education throughout their disease trajectory. Nurses and health care professionals must therefore ask their patients what kind of education they need at every follow‐up throughout the disease course.
MRI of healthy brain aging: A review
Authors: MacDonald M. Ethan , Pike G. Bruce
Published: June 2021

We present a review of the characterization of healthy brain aging using MRI with an emphasis on morphology, lesions, and quantitative MR parameters. A scope review found 6612 articles encompassing the keywords “Brain Aging” and “Magnetic Resonance”; papers involving functional MRI or not involving imaging of healthy human brain aging were discarded, leaving 2246 articles. We first consider some of the biogerontological mechanisms of aging, and the consequences of aging in terms of cognition and onset of disease. Morphological changes with aging are reviewed for the whole brain, cerebral cortex, white matter, subcortical gray matter, and other individual structures. In general, volume and cortical thickness decline with age, beginning in mid‐life. Prevalent silent lesions such as white matter hyperintensities, microbleeds, and lacunar infarcts are also observed with increasing frequency. The literature regarding quantitative MR parameter changes includes T1, T2, T2*, magnetic susceptibility, spectroscopy, magnetization transfer, diffusion, and blood flow. We summarize the findings on how each of these parameters varies with aging. Finally, we examine how the aforementioned techniques have been used for age prediction. While relatively large in scope, we present a comprehensive review that should provide the reader with sound understanding of what MRI has been able to tell us about how the healthy brain ages.
Robust arterial spin labeling MRI measurement of pharmacologically induced perfusion change in rat kidneys
Authors: Zhao Fuqiang , Zhou Xiaoyan , Messina Eric , Hu Lufei , Holahan Marie A. , Swaminath Gayathri , Hines Catherine D. G.
Published: June 2021

Kidney diseases such as acute kidney injury, diabetic nephropathy and chronic kidney disease (CKD) are related to dysfunctions of the microvasculature in the kidney causing a decrease in renal blood perfusion (RBP). Pharmacological intervention to improve the function of the microvasculature is a viable strategy for the potential treatment of these diseases. The measurement of RBP is a reliable biomarker to evaluate the efficacy of pharmacological agents' actions on the microvasculature, and measurement of RBP responses to different pharmacological agents can also help elucidate the mechanism of hemodynamic regulation in the kidney. Magnetic resonance imaging (MRI) with flow‐sensitive alternating inversion recovery (FAIR) arterial spin labeling (ASL) has been used to measure RBP in humans and animals. However, artifacts caused by respiratory and peristaltic motions limit the potential of FAIR ASL in drug discovery and kidney research. In this study, the combined anesthesia protocol of inactin with a low dose of isoflurane was used to fully suppress peristalsis in rats, which were ventilated with an MRI‐synchronized ventilator. FAIR ASL data were acquired in eight axial slices using a single‐shot, gradient‐echo, echo‐planar imaging (EPI) sequence. The artifacts in the FAIR ASL RBP measurement due to respiratory and peristaltic motions were substantially eliminated. The RBP responses to fenoldopam and L‐NAME were measured, and the increase and decrease in RBP caused by fenoldopam and L‐NAME, respectively, were robustly observed. To further validate FAIR ASL, the renal blood flow (RBF) responses to the same agents were measured by an invasive perivascular flow probe method. The pharmacological agent‐induced responses in RBP and RBF are similar. This indicates that FAIR ASL has the sensitivity to measure pharmacologically induced changes in RBP. FAIR ASL with multislice EPI can be a valuable tool for supporting drug discovery, and for elucidating the mechanism of hemodynamic regulation in kidneys.
A stabilized computational nonlocal poromechanics model for dynamic analysis of saturated porous media
Authors: Menon Shashank , Song Xiaoyu
Published: June 2021

In this article we formulate a stable computational nonlocal poromechanics model for dynamic analysis of saturated porous media. As a novelty, the stabilization formulation eliminates zero‐energy modes associated with the original multiphase correspondence constitutive models in the coupled nonlocal poromechanics model. The two‐phase stabilization scheme is formulated based on an energy method that incorporates inhomogeneous solid deformation and fluid flow. In this method, the nonlocal formulations of skeleton strain energy and fluid flow dissipation energy equate to their local formulations. The stable coupled nonlocal poromechanics model is solved for dynamic analysis by an implicit time integration scheme. As a new contribution, we validate the coupled stabilization formulation by comparing numerical results with analytical and finite element solutions for one‐dimensional and two‐dimensional dynamic problems in saturated porous media. Numerical examples of dynamic strain localization in saturated porous media are presented to demonstrate the efficacy of the stable coupled poromechanics framework for localized failure under dynamic loads.
Single-Center Analysis of Characteristics and Outcomes of De Novo, Concurrent, and Transformed Diffuse Large B-Cell Lymphoma
Authors: Desai Sanjal , Chaturvedi Mansi , Hameed Rumaisa , Baez-sosa Valentina , Shenoy Aarthi G.
Published: June 2021

Outcomes of diffuse large B-cell lymphoma (DLBCL), either concurrent with or transformed from indolent lymphoma, treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone are described in retrospective studies. The efficacy of other regimens in transformed or concurrent DLBCL is largely unknown. In this single-center retrospective study, we present characteristics of concurrent and transformed DLBCL and outcomes after dose-adjusted etoposide, vincristine, cyclophosphamide, prednisone, and doxorubicin with rituximab (DA-EPOCH-R) comparative with de novo DLBCL. Of 170 patients with DLBCL, 136 were de novo, 17 were concurrent, and 17 were transformed. Transformed DLBCL had significantly lower complete response rates and progression-free survival (PFS) but similar overall survival (OS) compared with de novo counterpart. There was no significant difference between de novo and concurrent DLBCL regarding response rates, PFS, and OS. DA-EPOCH-R was associated with inferior OS. Thus, intensified treatment with DA-EPOCH-R might not improve outcomes of transformed DLBCL.
A Coordinated Clinical Center for Young Onset Colorectal Cancer
Authors: Mendelsohn Robin , Palmaira Randze Lerie , Lumish Melissa , Bacani Joseph , Krishnan Asha , Weiss Jill , Semler Rosemary , Casson Anne , Arkema Ashley , Carter Jeanne , Nelson Christian , Mulhall John , Garcia-Aguilar Julio , Stadler Zsofia , Maya Hadley , Cercek Andrea
Published: June 2021

The increase in young onset colorectal cancer and the complex care needs of young cancer patients spurred the development of the Center for Young Onset Colorectal Cancer at the Memorial Sloan Kettering Cancer Center. This article describes the lessons of the first 2 years at the Center, including development of the program and specific services provided.
Nature documentaries as catalysts for change: Mapping out the ‘Blackfish Effect’
Authors: Boissat Laure , Thomas‐Walters Laura , Veríssimo Diogo
Published: June 2021

It is essential for us to understand what drives human behaviour if we want to tackle anthropogenic damage to the environment. Popular media can play an important role in shaping public attitudes, behaviours and norms towards wildlife, and documentaries in particular have become an increasingly prominent tool for social change. There is, however, a need for robust impact evaluation both in documentary‐making and in conservation, to refine future interventions.

The 2013 documentary Blackfish portrayed human–orca interactions at the US‐based marine park, SeaWorld. Following its release, SeaWorld suffered financial difficulties and the company underwent structural changes, including a cessation of its orca breeding programme. These impacts have often been attributed to the Blackfish documentary, but little evidence has been provided to justify these claims. We combined an analysis of stock market data and semi‐structured interviews with 26 key informants to build an in‐depth contribution analysis. We used General Elimination Methodology, a qualitative impact evaluation methodology to build an understanding of the impact of Blackfish.

We found a consensus among stakeholder groups that Blackfish induced negative publicity for SeaWorld and a change in people's perceptions of captivity. As a result, attendance at the park decreased and the market value of the company dropped. Blackfish catalysed a whole movement against marine mammal captivity. There were three key factors that led to its impact: the support from major distribution channels which allowed it to reach major audiences, emotional impact of the content and timing of its release. Blackfish benefitted from a perfect storm, building upon decades of activism to create an appropriate cultural climate for its release in 2013.

A free Plain Language Summary can be found within the Supporting Information of this article.
Optical mesoscopy, machine learning, and computational microscopy enable high information content diagnostic imaging of blood films
Authors: Shaw Michael , Claveau Rémy , Manescu Petru , Elmi Muna , Brown Biobele J , Scrimgeour Ross , Kölln Lisa S , McConnell Gail , Fernandez‐Reyes Delmiro
Published: June 2021

Automated image‐based assessment of blood films has tremendous potential to support clinical haematology within overstretched healthcare systems. To achieve this, efficient and reliable digital capture of the rich diagnostic information contained within a blood film is a critical first step. However, this is often challenging, and in many cases entirely unfeasible, with the microscopes typically used in haematology due to the fundamental trade‐off between magnification and spatial resolution. To address this, we investigated three state‐of‐the‐art approaches to microscopic imaging of blood films which leverage recent advances in optical and computational imaging and analysis to increase the information capture capacity of the optical microscope: optical mesoscopy, which uses a giant microscope objective (Mesolens) to enable high‐resolution imaging at low magnification; Fourier ptychographic microscopy, a computational imaging method which relies on oblique illumination with a series of LEDs to capture high‐resolution information; and deep neural networks which can be trained to increase the quality of low magnification, low resolution images. We compare and contrast the performance of these techniques for blood film imaging for the exemplar case of Giemsa‐stained peripheral blood smears. Using computational image analysis and shape‐based object classification, we demonstrate their use for automated analysis of red blood cell morphology and visualization and detection of small blood‐borne parasites such as the malarial parasite Plasmodium falciparum. Our results demonstrate that these new methods greatly increase the information capturing capacity of the light microscope, with transformative potential for haematology and more generally across digital pathology. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.
No effect modification of influenza virus vaccine effectiveness by age or chronic condition was observed in the 2010/11 to 2017/18 seasons
Authors: Machado Ausenda , Leite Andreia , Larrauri Amparo , Gomez Verónica , Rodrigues Ana Paula , Kislaya Irina , Nunes Baltazar
Published: June 2021

Purpose

Most European influenza vaccine strategies target individuals at higher risk of complications, which include, among others, individuals aged ≥65 years and with chronic conditions. These individuals not only have a high‐risk of post‐infection complications but also could have lower capacity of acquiring adequate vaccine‐induced protection. As such, chronic conditions and age could modify the effect of vaccines. This study aimed at assessing the potential effect modification of influenza vaccine effectiveness (IVE) by age and chronic conditions.

Methods

We used eight‐season data from the Portuguese vaccine effectiveness study. Every season, physicians at primary care units recruited patients with influenza‐like illness. Clinical data and swabs were collected for Reverse Transverse Polymerase Chain Reaction (RT‐PCR) detection of influenza. Trivalent inactivated IVE was estimated as 1 – odds ratio (OR) of being vaccinated in cases (RT‐PCR positive for influenza) versus negative controls. ORs were obtained using a multivariable conditional logistic regression model, paired by week of onset within each season. Confounders were assessed by designing a specific causal diagram. Age (< 65 or ≥65 years) and chronic conditions (diabetes, cardiovascular disease, chronic renal disease, chronic hepatic disease, obesity, chronic respiratory disease, and congenital or acquired immunodeficiency) were studied as effect modifiers by including an interaction term in the regression models. Significance was established at 5%.

Results

Point estimates indicate a higher IVE in the chronic condition strata compared to that in the no chronic condition strata. Regarding age, different results were obtained considering the virus type and (sub)type. When comparing the ≥65 years with the <65 years of age strata, we observed a higher IVE against A(H1N1)pdm09, an equal IVE against A(H3N2) and a lower IVE against B virus. However, all interaction terms were statistically insignificant, and this may be due to a small sample size.

Conclusion

The potential effect modification of age or chronic condition was not observed within our study.
Improving access to cancer information and supportive care services: A systematic review of mechanisms applied to link people with cancer to psychosocial supportive care services
Authors: White Victoria M. , Pejoski Natalie , Vella Elizabeth , Skaczkowski Gemma , Ugalde Anna , Yuen Eva Y. N. , Livingston Patricia , Wilson Carlene
Published: June 2021

Objective

Previous research has described the low uptake of psychosocial support services in people living with cancer. While characteristics of individuals using services have been examined, mechanisms applied to link individuals to support services are less frequently considered. This review aims to identify the mechanisms used to link people with cancer to support services and assess their impact.

Methods

Systematic searches of Pubmed, CINAHL, EMBASE and PsycINFO were conducted up to May 2020. Studies reporting service use associated with mechanisms to link adults with cancer to support services targeting emotional, informational, practical or social support needs were eligible. Eligible study designs included controlled trials, pre‐post designs and observational studies. Study quality was assessed and a narrative synthesis of findings undertaken.

Results

A total of 10 papers (from 8,037 unique titles) were eligible. Testing the feasibility of the linkage mechanism was the primary aim in five (50%) studies. Three linkage mechanisms were identified: (a) outreach from the support service; (b) clinician recommendation/referral; (c) mailed invitation. Outreach was the most successful in connecting people with cancer to services (52%–90% use); clinician recommendation/referral was least successful (3%–28%). The impact of different linkage mechanisms for different demographic groups was not assessed.

Conclusions

Outreach from services shows the most potential for increasing access to support services. However, the limited number of studies and limitations in the types of support services people with cancer were linked to, demonstrated the need for further work in this area. Identifying mechanisms that are effective for underserved, high‐needs patient groups is also needed.
A compact valveless pressure control source for soft rehabilitation glove
Authors: Ahmadjou Ahmadreza , Sadeghi Sajad , Zareinejad Mohammad , Talebi Heidar Ali
Published: June 2021

Background

Soft pneumatic robots have shown great promises in hand rehabilitation systems as alternatives to conventional rigid systems. However, their application is limited to clinical rehabilitation programs due to their dependency on large‐sized compressors as air suppliers. This disadvantage triggered the search for compact portable pneumatic sources.

Method

A compact valveless pneumatic source to control the bending angle of a soft actuator is proposed in this paper. The source incorporates two series of serially connected commercially available microcompressors to provide additional pressure and flowrate in two directions. In the proposed design, an inner‐loop controller, controls the output characteristics of the source while an outer‐loop controller handles the trajectory tracking of the angular position.

Results

Experimental results show that the source is capable of providing up to 160 kPa of output. The controller is able to track up to 2 rad/sec sinusoidal trajectory with a maximum 0.066 rad root‐mean‐square error.

Conclusion

Experimental measurements showed satisfactory results in the maximum ratings and tracking errors whilst relatively low average power was consumed by eliminating control valves.