bluuebunny/crossref_metadata_2025 huggingface dataset:
Different binding characteristics of ciprofloxacin to iron mineral surfaces: Thermodynamic evidence and site energy distribution analysis
Authors: Li Xiangzhi , Lei Feifei , Li Binghua , Bi Erping
Published: March 2021

Iron minerals in soil play an important role in controlling the migration of fluoroquinolones. In this study, batch experiments were carried out to investigate interactions in ciprofloxacin (CIP) adsorption to goethite, hematite, and magnetite at pH 6.0. Thermodynamics and the site energy distribution theory (SEDT) were adopted to clarify the complexation types. Using the adsorption results, pH‐dependent interactions were qualitatively elucidated. The thermodynamic data revealed the difference in adsorption mechanisms. With increasing sorbate loading, CIP adsorption to hematite and magnetite was endothermic, and both enthalpy change and entropy change decreased; however, CIP sorption to goethite showed opposite characteristics. The higher adsorption capacity and affinity of CIP to hematite and magnetite than those to goethite were caused by their higher site energy of the highest occurring frequency (E0*) and the temperature‐dependent average site energy, respectively. The E0* on the surface of goethite was about 17–19 kJ mol−1, where E0* values of hematite and magnetite were 20–26 kJ mol−1. When temperature increased from 289.15 to 308.15 K, the high‐ and low‐energy site densities for three iron minerals changed by −32 to 167% and by −36 to 223%, respectively. The different thermodynamic and SEDT results indicated that CIP adsorption mechanisms to goethite and hematite/magnetite were mainly outer‐ and inner‐sphere complexation, respectively. The findings of this study reveal the adsorption mechanisms and are helpful in evaluating the transport of antibiotics in soils containing typical iron minerals.
Extracellular vesicles derived from oesophageal cancer containing P4HB promote muscle wasting via regulating PHGDH/Bcl‐2/caspase‐3 pathway
Authors: Gao Xiaohan , Wang Yan , Lu Fang , Chen Xu , Yang Di , Cao Yiren , Zhang Weimin , Chen Jie , Zheng Leilei , Wang Guangchao , Fu Ming , Ma Liying , Song Yongmei , Zhan Qimin
Published: March 2021

Cachexia, characterized by loss of skeletal muscle mass and function, is estimated to inflict the majority of patients with oesophageal squamous cell carcinoma (ESCC) and associated with their poor prognosis. However, its underlying mechanisms remain elusive. Here, we developed an ESCC‐induced cachexia mouse model using human xenograft ESCC cell lines and found that ESCC‐derived extracellular vesicles (EVs) containing prolyl 4‐hydroxylase subunit beta (P4HB) induced apoptosis of skeletal muscle cells. We further identified that P4HB promoted apoptotic response through activating ubiquitin‐dependent proteolytic pathway and regulated the stability of phosphoglycerate dehydrogenase (PHGDH) and subsequent antiapoptotic protein Bcl‐2. Additionally, we proved that the P4HB inhibitor, CCF642, not only rescued apoptosis of muscle cells in vitro, but also prevented body weight loss and muscle wasting in ESCC‐induced cachexia mouse model. Overall, these findings demonstrate a novel pathway for ESCC‐induced muscle wasting and advocate for the development of P4HB as a potential intervention target for cachexia in patients with ESCC.
Human milk extracellular vesicles target nodes in interconnected signalling pathways that enhance oral epithelial barrier function and dampen immune responses
Authors: Zonneveld Marijke I. , van Herwijnen Martijn J.C. , Fernandez‐Gutierrez Marcela M. , Giovanazzi Alberta , de Groot Anne Marit , Kleinjan Marije , van Capel Toni M.M. , Sijts Alice J.A.M. , Taams Leonie S. , Garssen Johan , de Jong Esther C. , Kleerebezem Michiel , Nolte‐’t Hoen Esther N.M. , Redegeld Frank A. , Wauben Marca H.M.
Published: March 2021

Maternal milk is nature's first functional food. It plays a crucial role in the development of the infant's gastrointestinal (GI) tract and the immune system. Extracellular vesicles (EVs) are a heterogeneous population of lipid bilayer enclosed vesicles released by cells for intercellular communication and are a component of milk. Recently, we discovered that human milk EVs contain a unique proteome compared to other milk components. Here, we show that physiological concentrations of milk EVs support epithelial barrier function by increasing cell migration via the p38 MAPK pathway. Additionally, milk EVs inhibit agonist‐induced activation of endosomal Toll like receptors TLR3 and TLR9. Furthermore, milk EVs directly inhibit activation of CD4+ T cells by temporarily suppressing T cell activation without inducing tolerance. We show that milk EV proteins target key hotspots of signalling networks that can modulate cellular processes in various cell types of the GI tract.
The impact of coronavirus disease 2019 on surveillance colonoscopies in South Australia
Authors: Wassie Molla M , Agaciak Madelyn , Cock Charles , Bampton Peter , Young Graeme P , Symonds Erin L
Published: March 2021

Background and Aim

The coronavirus disease 2019 (COVID‐19) global pandemic has affected elective procedures, including colonoscopy, worldwide. Delayed colorectal cancer surveillance may increase cancer risk. This study aimed to determine the impact of COVID‐19 on the proportion of surveillance colonoscopies booked and completed and the extent to which that surveillance was delayed.

Methods

This was a retrospective analysis of colonoscopy data during the 3 months (April–June 2020) when clinical services were most affected by COVID‐19 in South Australia compared to the same period in 2019. Data on colonoscopies and responses to surveillance recall letters were reviewed to determine the numbers and proportions of colonoscopies that were delayed.

Results

During 2020, the total number of colonoscopies decreased by 51.1% (n = 569) compared to 2019 (n = 1164). In 2019, 45.5% (n = 530) of colonoscopies were completed for surveillance, but this proportion decreased to 32.0% (n = 182) during 2020, an overall decrease in the number of surveillance colonoscopies of 65.6%. Of surveillance colonoscopies that were due in 2020, 46.1% (134/291) were delayed >6 months, a significant increase compared to 2019 (19.3%; 59/306, P < 0.001). A decrease in response to surveillance recall letters was only observed in patients ≥75 years, with more nonresponders (51.6%) in 2020 compared to that observed in 2019 (25.6%, P = 0.03).

Conclusions

Significant delays in surveillance colonoscopies occurred during the COVID‐19 pandemic in South Australia. These effects are likely to be in areas more severely affected by the pandemic. Planning for post‐COVID‐19 colonoscopy capacity is required to avoid cancer progression due to delays in surveillance colonoscopies.
COVID‐19: Small and medium enterprises challenges and responses with creativity, innovation, and entrepreneurship
Authors: Thukral Esha
Published: March 2021

SMEs are significantly affected by COVID‐19 crisis as they overrepresent hardest‐hit sectors such as retail, hospitality, food services, entertainment services, and construction. The discovery and the spread of COVID‐19 in the absence of cure have led governments to take drastic measures, including the lockdown of large parts of society and social distancing resulting in behavioral changes. Some SMEs are responding to the crisis by applying creativity to problems to obtain opportunities. However, it is because of resilience that they can see an opportunity in chaos and survive uncertain times, but, to convert those opportunities to reality, some government interventions are needed to correct the negative effects of lockdown restrictions by revitalizing the entrepreneurial ecosystem.
Agri‐food sector and entrepreneurship during the COVID‐19 crisis: A systematic literature review and research agenda
Authors: Apostolopoulos Nikolaos , Ratten Vanessa , Petropoulos Dimitrios , Liargovas Panagiotis , Anastasopoulou Eleni
Published: March 2021

The related literature highlighted the impact of COVID‐19 on agri‐food entrepreneurship, the government measures and support on agri‐food entrepreneurship, and the shift of agri‐food entrepreneurship towards digitization, innovative ideas, and new market solutions. Agri‐food entrepreneurship faces numerous challenges, but at the same time, the crisis can generate opportunities. The studies made so far indicate that COVID‐19 can cause transformational changes to agri‐food entrepreneurship, although further research is needed to clarify open issues.
Touristic preferences of hostel guests during COVID‐19 times: The case of Oporto
Authors: Tavares Fernando , Condurú Olavo , Santos Eulália , Tavares Vasco
Published: March 2021

The hostel market urgently needs to reinvent itself and define strategies to increase its revenue, providing safety to its guests during the COVID‐19 pandemic. In the trip's planning, the results show that individuals attribute high levels of importance to cuisine, local wines and to meeting new people. The social networks of the different places to visit are the least utilized means to plan what to do during their stay in Oporto. Static street advertising and leaving the hostel to go outside are much more important to hostel customers. The most notable attractions are the Ribeira and the bridges over the river Douro.
The role of the fourth sector in the context of the COVID‐19 pandemic
Authors: Martins Vanessa , Ferreira Marisa , Braga Vitor
Published: March 2021

The fourth sector, which is composed of “for‐benefit” enterprises, can play a fundamental and positive role for the community, particularly in the context of the COVID‐19 pandemic. It supports public organizations and protects disadvantaged populations. Further research is suggested on the cross‐sectoral collaboration based on non‐profit motivations during the pandemic.
Cleft Palate Patient With Conductive Hearing Loss Due to Stapes Fixation
Authors: Özdemir Ozan , Övünç Okan , Yiğit Özgür
Published: March 2021

Congenital stapes fixation is characterized by congenital conductive hearing loss that is not progressive. This rare disease may be accompanied by additional middle ear anomalies. However, the occurrence of congenital stapes fixation with cleft palate and oligodontia was described by Gorlin et al. in 1973, and no further cases have been reported in the literature. Congenital stapes fixation was detected after the exploratory tympanotomy operation performed on a 15‐year‐old male patient admitted to our clinic with hearing loss, more prominent on the left. The patient also had a previous operation due to cleft lip and had congenital deficiencies in the upper and lower teeth. We present the second case report in the literature which we think belongs to this syndrome, which is defined as cleft palate, stapes fixation, and oligodontia syndrome by Gorlin et al. Laryngoscope, 131:E1279–E1281, 2021
Root system plays an important role in responses of plant to drought in the steppe of China
Authors: Jiang Lubing , Liu Hongyan , Peng Zhaoyu , Dai Jingyu , Zhao Fengjun , Chen Zhiting
Published: March 2021

In the temperate grasslands of northern China, there exists a large range of soil texture. However, previous studies have mainly focused on the effect of climate water deficit on plant traits and have paid little attention to the effect of soil water deficit because grasses tend to use rainfall water directly. We measured eight drought‐related plant traits of 12 widely distributed perennial species in the temperate grassland in northern China and examined drought‐related plant traits under different aridity index ([ET0 − P]/ET0) and soil sand/clay ratio. The 12 species were categorized into three functional groups: fibrous‐rooted C4 species, fibrous‐rooted C3 species, and tap‐rooted C3 species. Our results showed that increasing climate drought had influence on all selected functional groups, and the influence on aboveground biomass and height was especially large on fibrous‐rooted C3 species. Coarse soil led to increased root length of fibrous‐rooted C3 and tap‐rooted C3 species. Our results imply that root system can be important to plant responses under drought, and soil texture can have influence on plant, though most of the traits show resistance to coarser soil.
Study on the effect of stepwise decreasing microwave power drying (SDMPD) of moth bean sprouts on its quality
Authors: Sedani Sejal R. , Pardeshi Ishvar L. , Dorkar Amit R.
Published: March 2021

Vigna aconitifolia (Jacq.), locally known as moth bean, is a drought‐resistant pulse crop and grown in arid and semi‐arid areas of India. Green pods and grains, in cooked or sprouted form, are a mostly consumable part of the plant as they are rich in protein. Sprouting increases the bioavailability of protein by 30%, but bacterial contamination is high in sprouts due to its high initial moisture content that creates a problem for its storage. Hence, to rectify the said problem, drying the sprouts up to storable moisture level can be the best solution. The microwave drying was investigated for drying of sprouted moth beans. The microwave drying of sprouted moth beans using single microwave power was not suitable for drying, as the burning of the product takes place before reaching desired moisture content while dried at a microwave power of 900, 720, 540, and 360 W. During the drying at a microwave power of 180 W, it took about an hour for drying. However, during this drying, by the time it reaches moisture content at around 57.89 kg per 100 kg dm, the product shows browning. Therefore, a new technique was employed for drying sprouted moth beans, that is, Stepwise Decreasing Microwave Power Drying (SDMPD). The sprouts were dried at each microwave power level, in decreasing order for a particular time at each respective microwave power, to reduce the browning effect thus protecting the product from burning. The sprouted moth beans were dried in 19 min using SDMPD. The rehydration ratio was found to be 1.96. The moisture content of resultant dried sprouted moth beans was found to be 4.95 kg per 100 kg dm with a minimum color change (∆e*) of 10.46, which was found to be reduced up to 6.84 after rehydration, indicating the improved color.
Predictors of otolaryngology applicant success using the Texas STAR database
Authors: Lenze Nicholas R. , Mihalic Angela P. , DeMason Christine E. , Shah Rupali N. , Buckmire Robert A. , Thorp Brian D. , Ebert Charles S. , Zanation Adam M.
Published: March 2021

Objectives

To examine applicant characteristics and behaviors associated with a successful match into otolaryngology residency.

Methods

Self‐reported survey data from applicants to otolaryngology residency between 2018 and 2020 were obtained from the Texas STAR database. Characteristics and predictors associated with a successful match were examined using Chi‐square tests, two‐sided t‐tests, and logistic regression models.

Results

A total of 315 otolaryngology residency applicants responded to the survey of whom 274 matched (87%) and 41 did not match (13%). Matched applicants had a significantly higher mean USMLE Step 1 score (P = .016) and Step 2 CK score (P = .007). There were no significant differences in AOA status (45% vs 36%; P = .207), mean number of applications submitted (70 vs 69; P = .544), and mean number of away rotations (2.1 vs 2.0; P = .687) between matched and unmatched applicants. Significant predictors of a successful match included receiving honors in 5 or more clerkships (OR 2.0, 95% CI 1.0‐4.0; P = .040), receiving honors in an ENT clerkship (OR 3.7, 95% CI 1.0‐12.9; P = .044), and having 3 or more peer‐reviewed publications (OR 2.3, 95% CI 1.1‐4.5; P = .020). The majority of applicants (79.9%) matched at a program where they either did an away rotation, had a personal geographic connection, or attended medical school in the same geographic region.

Conclusions

Board scores, excelling on clinical rotations, and having productive research experience appear to be strong predictors of a successful match in otolaryngology. The majority of applicants report a personal or geographic connection to the program at which they match.

Level of evidence

4.
Effects of Anti‐Inflammatory Nanofibers on Urethral Healing
Authors: Chan Yvonne Y. , Bury Matthew I. , Fuller Natalie J. , Nolan Bonnie G. , Gerbie Emily Yura , Hofer Matthias D. , Sharma Arun K.
Published: March 2021

Protracted postsurgical inflammation leading to postoperative complications remains a persistent problem in urethral reconstruction. Nanofibers in the form of peptide amphiphiles expressing anti‐inflammatory peptides (AIF‐PA) have positively modulated local inflammatory responses. Urethroplasty is performed to repair 5 mm ventral urethral defects with: uncoated small intestinal submucosa (SIS); SIS dip‐coated with AIF‐PA1 (anti‐inflammatory treatment), or SIS dip‐coated with AIF‐PA6 (control) on 12‐week‐old male Sprague Dawley rats (n = 6/group/timepoint). Animals are euthanized at 14 and 28 d postsurgery. Hematoxylin‐eosin, Masson's Trichrome, and immunohistochemistry with primary antibodies against myeloperoxidase (MPO; neutrophils), CD68, CD86, CD206 (macrophages), and proinflammatory cytokines TNFα and IL‐1β are performed. Complete urethral healing occurs in 3/6 uncoated SIS (50%), 2/6 SIS+AIF‐PA6 (33.3%), and 5/6 SIS+AIF‐PA1 (83.3%) animals at 14 d and all at 28 d. Application of AIF‐PA1 to SIS substitution urethroplasty decreases MPO+ neutrophils, CD86+ M1 proinflammatory macrophages, TNFα, and IL‐1β levels while concurrently increasing levels of CD206+ M2 proregenerative/anti‐inflammatory macrophages at the anastomoses and the regenerated tissue at the wound bed (REGEN). AIF‐PA1 treatment enhances the healing process, contributing to earlier, complete urethral healing, and increased angiogenesis. Further studies are needed to elucidate the specific mechanism of inflammatory response modulation on angiogenesis and overall urethral healing.
Full Bio‐Based Soy Protein Isolate Film Enhanced by Chicken Feather Keratin
Authors: Li Xiaona , Wei Yanqiang , Jiang Shuaicheng , Zhou Ying , Li Jiongjiong , Li Kuang , Shi Sheldon Q. , Li Jianzhang
Published: March 2021

Soy protein isolate (SPI) film is considered a promising biomaterial for the replacement of petroleum‐based food packaging plastics. However, current SPI films are still replying on petroleum‐based crosslink agents. In this paper, a green and effective approach is developed to prepare a full biomass‐based sustainable film with high strength and toughness by incorporating feather keratin (FK, extracted from the waste chicken feathers) into the SPI via the reaction of disulfide bonds. The broken disulfide bonds in FK are recombined with the sulfhydryl group on the SPI molecular chains to form a cross‐linked network. Compared to the SPI film, the tensile strength of the SPI/FK composite film is increased by 242% to 8.2 MPa and the toughness is increased by 152% to 9.18 MJ m−3. The thermal stability and the water resistance of the SPI/FK composite films are also improved. The replacement rate of FK‐modified SPI is up to 40%. Since the film is 100% made from bio‐based materials, it would be biodegradable. This research provides a green and economic approach to improve the performance of protein‐based food packaging films by introducing FK as an enhancer and constructing disulfide bonds cross‐linked network structure in the protein system.
A bibliometric retrospection of marketing from the lens of psychology: Insights from Psychology & Marketing
Authors: Donthu Naveen , Kumar Satish , Pattnaik Debidutta , Lim Weng M.
Published: March 2021

The contribution of psychology to marketing has been significant and invaluable. No discipline has benefitted from another as much as marketing from psychology. To gain an understanding of the scientific contributions emerging from the intersection of psychology and marketing, this study conducts a bibliometric retrospection of a premier journal dedicated to the application of psychological theories and techniques to marketing: Psychology & Marketing (P&M). To do so, this study employs bibliometrics to unpack the publication trends and the intellectual structure of P&M. In doing so, this study reveals several interesting findings. First, P&M's publications grew by 71.9 times, authorships grew by 82.1 times, and citations grew by 150.8 times between 1984 and 2020, indicating a healthy growth of marketing research informed by psychology. Second, P&M's contributions manifest through eight intellectual clusters—namely, marketing environment; consumer engagement; online consumer behavior and marketing; luxury consumption and marketing; sustainable consumption and marketing; influencer and international marketing; customer relationship, satisfaction, and loyalty; and marketing futures. Finally, P&M's emerging and promising areas for future exploration include aesthetics and consumer impressions; celebrity endorsement; conspicuous consumption and hedonic adaptation; climate change; choice likelihood; consumer engagement; consumer psychology; marketing communication; sensory marketing; sharing economy; and social media marketing. As a whole, these findings should provide readers with a state‐of‐the‐art overview of marketing from psychology through the scientific contributions from P&M.
3D Antidrying Antifreezing Artificial Skin Device with Self‐Healing and Touch Sensing Capability
Authors: Shin Woohyeon , Kim Jun Seop , Choi Hui Ju , Kim Heesung , Park Sulbin , Lee Hee Jung , Choi Moon Kee , Chung Kyeongwoon
Published: March 2021

Hydrogels are attractive, active materials for various e‐skin devices based on their unique functionalities such as flexibility and biocompatibility. Still, e‐skin devices are generally limited to simple structures, and the realization of optimal‐shaped 3D e‐skin devices for target applications is an intriguing issue of interest. Furthermore, hydrogels intrinsically suffer from drying and freezing issues in operational capability for practical applications. Herein, 3D artificial skin devices are demonstrated with highly improved device stability. The devices are fabricated in a target‐oriented 3D structure by extrusion‐based 3D printing, spontaneously heal mechanical damage, and enable stable device operation over time and under freezing conditions. Based on the material design to improve drying and freezing resistance, an organohydrogel, prepared by solvent displacement of hydrogel with ethylene glycol for 3 h, exhibits excellent drying resistance over 1000 h and improved freezing resistance by showing no phase transition down to −60 °C while maintaining its self‐healing functionality. Based on the improved drying and freezing resistance, artificial skin devices in target‐oriented optimal 3D structures are presented, which enable accurate positioning of touchpoints even on a complicated 3D structure stably over time and excellent operation at temperatures below 0 °C without losing their flexibility.
Novel SARS2 variants identified in a Chinese girl with HUPRA syndrome
Authors: Zhou Yi , Zhong Cheng , Yang Qin , Zhang Gaofu , Yang Haiping , Li Qiu , Wang Mo
Published: March 2021

Background

Hyperuricemia, pulmonary hypertension, renal failure, and alkaline intoxication syndrome (HUPRA syndrome) is a rare autosomal recessive mitochondrial disease. SARS2 gene encoding seryl‐tRNA synthetase is the only pathogenic gene of HUPRA syndrome. All the previously reported cases with HUPRA syndrome were detected for homozygous mutation.

Methods

We identified compound heterozygous mutations causing HUPRA syndrome using whole‐exome sequencing, and verifed pathogenicity with ACMG standards. All the previously published cases with SARS2 mutations were reviewed.

Results

SARS2 gene compound heterozygotes variants were detected in this Chinese patient (c.667G>A/c.1205G>A). Bioinformatics studies and protein models predict that a new variant (c.667G>A) is likely to be pathogenic. A total of six patients, five of whom were previously reported with HUPRA syndrome, were analyzed. All of the six had typical clinical manifestations of HUPRA syndrome, except the Chinese girl who had no pulmonary hypertension or alkaline intoxication. The shrunken kidney was more prominent in our proband. The average survival time for previously reported patients was 17 months, and the Chinese girl was 70 months. Three mutation variants were found, including five homozygous mutants, three of which were Palestinian (c.1169A > G), two of which were from a Spanish family (c.1205G> A), and one was a new variant (c.667G>A/c.1205G>A).

Conclusion

We found a new pathogenic form (compound heterozygous mutation) causing HUPRA syndrome, and identified a novel pathogenic site (c.667G>A) of the SARS2 gene, expanding the spectrum of SARS2 pathogenic variants. The mild phenotype in complex heterozygous mutations is described.
All‐systolic first‐pass myocardial rest perfusion at a long saturation time using simultaneous multi‐slice imaging and compressed sensing acceleration
Authors: Ferrazzi Giulio , McElroy Sarah , Neji Radhouene , Kunze Karl P. , Nazir Muhummad Sohaib , Speier Peter , Stäb Daniel , Forman Christoph , Razavi Reza , Chiribiri Amedeo , Roujol Sébastien
Published: March 2021

Purpose

To enable all‐systolic first‐pass rest myocardial perfusion with long saturation times. To investigate the change in perfusion contrast and dark rim artefacts through simulations and surrogate measurements.

Methods

Simulations were employed to investigate optimal saturation time for myocardium‐perfusion defect contrast and blood‐to‐myocardium signal ratios. Two saturation recovery blocks with long/short saturation times (LTS/STS) were employed to image 3 slices at end‐systole and diastole. Simultaneous multi‐slice balanced steady state free precession imaging and compressed sensing acceleration were combined. The sequence was compared to a 3 slice‐by‐slice clinical protocol in 10 patients. Quantitative assessment of myocardium‐peak pre contrast and blood‐to‐myocardium signal ratios, as well as qualitative assessment of perceived SNR, image quality, blurring, and dark rim artefacts, were performed.

Results

Simulations showed that with a bolus of 0.075 mmol/kg, a LTS of 240‐470 ms led to a relative increase in myocardium‐perfusion defect contrast of 34% ± 9%‐28% ± 27% than a STS = 120 ms, while reducing blood‐to‐myocardium signal ratio by 18% ± 10%‐32% ± 14% at peak myocardium. With a bolus of 0.05 mmol/kg, LTS was 320‐570 ms with an increase in myocardium‐perfusion defect contrast of 63% ± 13%‐62% ± 29%. Across patients, LTS led to an average increase in myocardium‐peak pre contrast of 59% (P < .001) at peak myocardium and a lower blood‐to‐myocardium signal ratio of 47% (P < .001) and 15% (P < .001) at peak blood/myocardium. LTS had improved motion robustness (P = .002), image quality (P < .001), and decreased dark rim artefacts (P = .008) than the clinical protocol.

Conclusion

All‐systolic rest perfusion can be achieved by combining simultaneous multi‐slice and compressed sensing acceleration, enabling 3‐slice cardiac coverage with reduced motion and dark rim artefacts. Numerical simulations indicate that myocardium‐perfusion defect contrast increases at LTS.
Quasi–steady‐state CEST (QUASS CEST) solution improves the accuracy of CEST quantification: QUASS CEST MRI‐based omega plot analysis
Authors: Sun Phillip Zhe
Published: March 2021

Purpose

CEST MRI omega plot quantifies the labile proton fraction ratio (fr) and exchange rate (ksw), yet it assumes long RF saturation time (Ts) and relaxation delay (Td). Our study aimed to test if a quasi–steady‐state (QUASS) CEST analysis that accounts for the effect of finite Ts and Td could improve the accuracy of CEST MRI quantification.

Methods

We modeled the MRI signal evolution using a typical CEST EPI sequence. The signal relaxes toward its thermal equilibrium following the bulk water relaxation rate during Td, and then toward its CEST steady state following the spin‐lock relaxation rate during Ts from which the QUASS CEST effect is derived. Both fr and ksw were solved from simulated conventional apparent CEST and QUASS CEST MRI. We also performed MRI experiments from a Cr‐gel phantom under serially varied Ts and Td times from 1.5 to 7.5 s.

Results

Simulation showed that, although ksw could be slightly overestimated (3%‐15%) for the range of Ts and Td, fr could be substantially underestimated by as much as 67%. In contrast, the QUASS solution provided accurate ksw and fr determination within 2%. The CEST MRI experiments confirmed that the QUASS solution enabled robust quantification of ksw and fr, superior over the omega plot analysis based on the conventional apparent CEST MRI measurements.

Conclusions

The QUASS CEST MRI algorithm corrects the effect of finite Ts and Td times on CEST measurements, thereby allowing robust and accurate CEST quantification.
Distortion‐free, high‐isotropic‐resolution diffusion MRI with gSlider BUDA‐EPI and multicoil dynamic B0 shimming
Authors: Liao Congyu , Bilgic Berkin , Tian Qiyuan , Stockmann Jason P. , Cao Xiaozhi , Fan Qiuyun , Iyer Siddharth Srinivasan , Wang Fuyixue , Ngamsombat Chanon , Lo Wei‐Ching , Manhard Mary Kate , Huang Susie Y. , Wald Lawrence L. , Setsompop Kawin
Published: March 2021

Purpose

We combine SNR‐efficient acquisition and model‐based reconstruction strategies with newly available hardware instrumentation to achieve distortion‐free in vivo diffusion MRI of the brain at submillimeter‐isotropic resolution with high fidelity and sensitivity on a clinical 3T scanner.

Methods

We propose blip‐up/down acquisition (BUDA) for multishot EPI using interleaved blip‐up/blip‐down phase encoding and incorporate B0 forward‐modeling into structured low‐rank reconstruction to enable distortion‐free and navigator‐free diffusion MRI. We further combine BUDA‐EPI with an SNR‐efficient simultaneous multislab acquisition (generalized slice‐dithered enhanced resolution [“gSlider”]), to achieve high‐isotropic‐resolution diffusion MRI. To validate gSlider BUDA‐EPI, whole‐brain diffusion data at 860‐μm and 780‐μm data sets were acquired. Finally, to improve the conditioning and minimize noise penalty in BUDA reconstruction at very high resolutions where B0 inhomogeneity can have a detrimental effect, the level of B0 inhomogeneity was reduced by incorporating slab‐by‐slab dynamic shimming with a 32‐channel AC/DC coil into the acquisition. Whole‐brain 600‐μm diffusion data were then acquired with this combined approach of gSlider BUDA‐EPI with dynamic shimming.

Results

The results of 860‐μm and 780‐μm datasets show high geometry fidelity with gSlider BUDA‐EPI. With dynamic shimming, the BUDA reconstruction’s noise penalty was further alleviated. This enables whole‐brain 600‐μm isotropic resolution diffusion imaging with high image quality.

Conclusions

The gSlider BUDA‐EPI method enables high‐quality, distortion‐free diffusion imaging across the whole brain at submillimeter resolution, where the use of multicoil dynamic B0 shimming further improves reconstruction performance, which can be particularly useful at very high resolutions.
MR spectroscopic imaging at 3 T and outcomes in surgical epilepsy
Authors: Pan Jullie W. , Antony Arun , Tal Assaf , Yushmanov Victor , Fong Joanna , Richardson Mark , Schirda Claud , Bagic Anto , Gonen Oded , Hetherington Hoby P.
Published: March 2021

For the spectroscopic assessment of brain disorders that require large‐volume coverage, the requirements of RF performance and field homogeneity are high. For epilepsy, this is also challenging given the inter‐patient variation in location, severity and subtlety of anatomical identification and its tendency to involve the temporal region. We apply a targeted method to examine the utility of large‐volume MR spectroscopic imaging (MRSI) in surgical epilepsy patients, implementing a two‐step acquisition, comprised of a 3D acquisition to cover the fronto‐parietal regions, and a contiguous parallel two‐slice Hadamard‐encoded acquisition to cover the temporal‐occipital region, both withTR/TE= 2000/40 ms and matched acquisition times. With restricted (static, first/second‐order)B0shimming in their respective regions, the Cramér‐Rao lower bounds for creatine from the temporal lobe two‐slice Hadamard and frontal‐parietal 3D acquisition are 8.1 ± 2.2% and 6.3 ± 1.9% respectively. The datasets are combined to provide a total 60 mm axial coverage over the frontal, parietal and superior temporal to middle temporal‐occipital regions. We applied these acquisitions at a nominal 400 mm3voxel resolution inn= 27 pre‐surgical epilepsy patients andn= 20 controls. In controls, 86.6 ± 3.2% voxels with at least 50% tissue (white + gray matter, excluding CSF) survived spectral quality inclusion criteria. Since all patients were clinically followed for at least 1 year after surgery, seizure frequency outcome was available for all. The MRSI measurements of the total fractional metabolic dysfunction (characterized by the Cr/NAA metric) in FreeSurfer MRI gray matter segmented regions, in the patients compared with the controls, exhibited a significant Spearman correlation with post‐surgical outcome. This finding suggests that a larger burden of metabolic dysfunction is seen in patients with poorer post‐surgical seizure control.
Amplify your efforts in higher education to create long‐lasting social change
Authors: Sutton Halley
Published: March 2021

Julie Coonrod, Ph.D., Dean of Graduate Studies at the University of New Mexico, was born and raised in Albuquerque. “I absolutely love everything about this place,” Coonrod said, adding that she's spent 25 years at the institution.
Reduced Order Models for Optimal Flow Control
Authors: Strazzullo Maria , Ballarin Francesco , Rozza Gianluigi
Published: March 2021

Data assimilation models allow to fill the gap between numerical simulations and experimental data. Optimal control problems governed by parametrized partial differential equations PDE(µ) is suited for this kind of application, where you want to track problem solutions towards known quantities, given by data collections or previous knowledge. Still, the computational effort increases when one has to deal with nonlinear time‐dependent governing equations. Reduced order methods are an effective approach to solve data assimilation problems in a reliable and faster way. We apply the POD‐Galerkin methodology in environmental marine sciences where different parameters describe several physical configurations. We present a nonlinear time‐dependent tracking problem for velocity‐height solutions of shallow water equations.
Data‐based Approach for Fault Diagnosis of Hydropower Rotors
Authors: Sperber Christian , Weber Wilhelm , Eberhard Peter
Published: March 2021

The poster presents a novel approach to diagnose rotordynamic faults like unbalance and coupling misalignment from measured vibration. For that purpose, a large database of virtual hydropower rotors and their vibration has been calculated. The goal is to create a data‐driven diagnosis system from this database, that will be applicable to a variety of real hydropower rotors. In a first step, a gradient boosting regression algorithm has been applied to the database with some preprocessing and showed promising results. A future condition monitoring system based on this idea will be easily applicable to a variety of hydropower rotors without the need of machine‐specific models. It will help machine operators to monitor faults in order to start targeted countermeasures when they are needed, avoiding unscheduled downtimes and increasing overall cost‐efficiency of their machine.
Wavelet‐based dynamic mode decomposition
Authors: Krishnan Manu , Gugercin Serkan , Tarazaga Pablo
Published: March 2021

Dynamic mode decomposition (DMD) has emerged as a leading data‐driven technique to identify the spatio‐temporal coherent structure in dynamical systems, owing to its strong relation with the Koopman operator. For dynamical systems with external forcing, the identified model should not only be suitable for a specific forcing function but should generally approximate the input‐output behavior of the data source. In this work, we propose a novel methodology, called the wavelet‐based DMD (WDMD), that integrates wavelet decompositions with ioDMD to approximate dynamical systems from partial measurement data. The method is validated using a numerical and experimental case study involving modal analysis on a simple finite element model and free‐free beam respectively.
Sensor selection for hyper‐parameterized linear Bayesian inverse problems
Authors: Aretz Nicole , Chen Peng , Veroy Karen
Published: March 2021

Models of physical processes often depend on parameters, such as material properties or source terms, that are only known with some uncertainty. Measurement data can be used to estimate these parameters and thereby improve the model's credibility. When measurements become expensive, it is important to choose the most informative data. This task becomes even more challenging when the model configurations vary and the data noise is correlated.

In this poster we summarize our results in [1] and present an observability coefficient that describes the influence of the sensors on the inverse solution. It can guide optimal sensor selection towards a uniformly good parameter estimate over all admissible model configurations. We propose a sensor selection algorithm that iteratively improves the observability coefficient, and present numerical results for a steady‐state heat conduction problem with correlated noise.
The effects of honey on pro‐ and anti‐inflammatory cytokines: A narrative review
Authors: Navaei‐Alipour Narges , Mastali Mohadeseh , Ferns Gordon A. , Saberi‐Karimian Maryam , Ghayour‐Mobarhan Majid
Published: March 2021

Honey contains flavonoids and phenolic acids, and because of their antioxidant and anti‐inflammatory properties, they may play an important role in human health. The purpose of this review was to synthesize the effects of natural honey on pro‐ and anti‐inflammatory cytokines. The effects of honey on wound healing and immunity appear to be inconsistent. The available databases )PubMed and Scopus) were searched and 42 studies were assessed. In patients with cancer, honey has been reported to inhibit the effects of pro‐inflammatory factors such as TNF‐α and IL‐6. In patients with neuro‐inflammatory disorders honey has been shown to inhibit the expression of pro‐inflammatory markers. It has also been reported that honey can reduce TNF‐α expression in conditions associated with liver injury, by suppressing TNF‐α converting enzyme activity. Honey inhibits APAP‐induced hepatocellular necrosis by modulating the expression of IL‐10 and IL‐1ß. Animal studies have shown that honey can reduce serum IL‐1ß, IL‐6 and TNF‐α concentration and increase IL‐10 concentrations in a model of gastric ulcer. Some studies in diabetics have shown that honey can reduce serum TNF‐α, IL‐6, IL‐1ß and TGF‐ß by inhibiting NF‐Kß. The source and type of honey and its component have not been indicated in various clinical and practical studies, which are a limitation of these studies, in relation to reproducing them. Sigma, Manuka, Gelam and Tulang honey have been used in most of the in vitro and animal studies. The animal studies have demonstrated similar effects on pro‐inflammatory factors, which include reducing serum TNF‐α, IL‐6 and IL‐1β as well as increasing IL‐10. There are few human RCTs investigating the effects of honey on inflammatory cytokines. Only one RCT has reported the type of honey that they have used. Tulang honey has been reported to increase serum TNF‐α and decrease hs‐CRP, which is therefore controversial. Further high‐quality studies are needed to firmly establish the clinical efficacy of honey. Because most studies had used different duration, type of honey and dosage, which make them difficult to contextualize, as the phytochemical content of a honey may depend on its source. Furthermore, it is unclear whether honey's anti‐inflammatory effects are related to its phenolic or tocopherol compounds, and whether its effects are greater than these individual components.
Spatial and temporal variations in near‐surface energy fluxes in an Alpine valley under synoptically undisturbed and clear‐sky conditions
Authors: Lehner Manuela , Rotach Mathias W. , Sfyri Eleni , Obleitner Friedrich
Published: March 2021

Diurnal cycles of turbulent sensible and latent heat fluxes are typically closely related to the diurnal cycles of solar irradiation under synoptically undisturbed and clear‐sky conditions. In mountainous terrain, large variations can occur in the topographic and surface properties, which modify the local radiation budget and thus turbulent energy fluxes and the surface energy balance. Another characteristic of mountainous terrain is local, thermally driven circulation systems, such as the slope‐ and valley‐wind system, which can equally affect turbulent exchange. Observations of near‐surface radiative and turbulent fluxes are presented from six eddy‐covariance stations in an approximately east–west‐oriented major Alpine valley for undisturbed and clear‐sky conditions. Median diurnal cycles over the whole year are compared at the six sites and related to local terrain characteristics and the thermally driven wind systems. At a scale that is smaller than grid cells in current operational global forecast models, heat, moisture, and momentum fluxes show a large spatial variability in the magnitudes and their diurnal cycles. Lowest heat fluxes are observed on the north‐facing sidewall, where solar irradiation and thus available energy are reduced compared with the valley floor and south‐facing sidewall. Differences in the land surface characteristics further affect the partitioning of the available energy into sensible and latent heat fluxes. The median sensible heat flux reaches its daily peak already before solar noon at several sites, which appears to be related to the transition from down‐valley to up‐valley winds. In contrast to flat and homogeneous terrain, horizontal heat fluxes and lateral momentum fluxes can reach magnitudes that are similar to the magnitudes of vertical heat fluxes and longitudinal momentum fluxes, respectively.
Computationally unraveling the mechanism and selectivity of five and six membered N‐heterocyclic carbene‐catalyzed alkyne hydrochalcogenation
Authors: Jayasree Elambalassery G. , Reshma Sobhana , Aswathy Mohanan
Published: March 2021

The present work is intended to bring to the forefront a relatively less explored area of N‐Heterocyclic Carbene (NHC) catalyzed alkyne hydro‐ thiolation and selenation reactions by exploring the reaction mechanism. Reaction mechanism involves chalcogenol activation followed by alkyne insertion and the second step is the rate determining step. A comparison with the reported uncatalyzed gas phase reaction showed that a simple imidazol‐2‐ylidene catalyst can lower the free energy barrier by 28.74 and 21.73 kcal/mol respectively for acetylene hydro‐ thiolation and selenation reaction. All the employed NHCs are proved to be better catalyst for both hydrothiolation and hydroselenation. Factors such as changing the heterocycle, increasing the conjugation, ring expansion and electronic/steric substitution at the heteroatom were found to affect the energy barriers due to the geometric variations at NHC‐carbon and S/Se in the intermediate and the transition structure corresponding to alkyne insertion. Effect of solvent polarity on the reaction energetics and selectivity has also been analyzed employing THF, DMSO and MeOH as the solvents.
Religiosity and work engagement: Workload as a moderator
Authors: Abualigah Ahmad , Davies Julie , Harrington Shelley
Published: March 2021

Based on job demands‐resources (JD‐R) theory, this study examines the relationship between religiosity‐from an Islamic lens‐and work engagement, and the moderating role of workload on the relationship between these constructs. The results of a survey of 381 Muslim employees in Jordanian telecoms reveal that religiosity is positively related to work engagement. The findings also illustrate the importance of differentiating between challenge and hindrance demands in stressful contexts where workload influences the benefits of religiosity for work engagement. This study highlights the applicability of JD‐R theory and extends the theoretical framework by examining the relationship between religiosity and work engagement. It contributes to work engagement literature by introducing religiosity as a personal resource which enhances work engagement and improves well‐being.
3d Transition‐Metal‐Mediated Columbite Nanocatalysts for Decentralized Electrosynthesis of Hydrogen Peroxide
Authors: Liu Chang , Li Hao , Chen Junsheng , Yu Zixun , Ru Qiang , Li Shuzhou , Henkelman Graeme , Wei Li , Chen Yuan
Published: March 2021

Decentralized electrosynthesis of hydrogen peroxide (H2O2) via oxygen reduction reaction (ORR) can enable applications in disinfection control, pulping and textile bleaching, wastewater treatment, and renewable energy storage. Transition metal oxides are usually not efficient catalysts because they are more selective to produce H2O. Here, it is shown that divalent 3d transition metal cations (Mn, Fe, Co, Ni, and Cu) can control the catalytic activity and selectivity of columbite nanoparticles. They are synthesized using polyoxoniobate (K7HNb6O19·13H2O) and divalent metal cations by a hydrothermal method. The optimal NiNb2O6 holds an H2O2 selectivity of 96% with the corresponding H2O2 Faradaic efficiency of 92% in a wide potential window from 0.2 to 0.6 V in alkaline electrolyte, superior to other transition metal oxide catalysts. Ex situ X‐ray photoelectron and operando Fourier‐transformed infrared spectroscopic studies, together with density functional theory calculations, reveal that 3d transition metals shift the d‐band center of catalytically active surface Nb atoms and change their interactions with ORR intermediates. In an application demonstration, NiNb2O6 delivers H2O2 productivity up to 1 molH2O2 gcat−1 h−1 in an H‐shaped electrolyzer and can yield catholytes containing 300 × 10−3 m H2O2 to efficiently decomposing several organic dyes. The low‐cost 3d transition‐metal‐mediated columbite catalysts show excellent application potentials.
Near‐Infrared Light‐Activatable Dual‐Action Nanoparticle Combats the Established Biofilms of Methicillin‐Resistant Staphylococcus aureus and Its Accompanying Inflammation
Authors: Yuan Zhang , Lin Chuanchuan , Dai Liangliang , He Ye , Hu Jingwei , Xu Kun , Tao Bailong , Liu Peng , Cai Kaiyong
Published: March 2021

Clinically, inhibition of both bacterial infection and excessive inflammation is a crucial step for improved wound treatments. Herein, the fabrication of near‐infrared‐light (NIR)‐activatable deoxyribonuclease (DNase)–carbon monoxide (CO)@mesoporous polydopamine nanoparticles (MPDA NPs) is demonstrated for efficient elimination of methicillin‐resistant Staphylococcus aureus (MRSA) biofilms and the following anti‐inflammatory activity. Specifically, thermosensitive CO‐gas‐releasing donors (CO releasing molecules, FeCO) are first encapsulated into MPDA NPs, followed by covalently immobilizing deoxyribonuclease I (DNase I) on the surfaces of MPDA NPs. DNase I can degrade the extracellular DNA in biofilms, which site specifically destroys the compactness of the biofilms. With NIR irradiation, DNase–CO@MPDA NPs display great photothermal ability, and further trigger on‐demand delivery of bactericidal CO gas that can adequately permeate the impaired biofilms. Eventually, they achieve effective MRSA biofilm elimination in virtue of the synergistic effects of both DNase I participation and CO‐gas‐potentiated photothermal therapy. Importantly, the inflammatory responses of DNase–CO@MPDA NPs and NIR‐treated wounds are simultaneously alleviated owing to the anti‐inflammatory features of released CO. Finally, NIR‐activatable DNase–CO@MPDA NPs accelerate the healing process of MRSA‐biofilm‐infected cutaneous wounds. Taken together, this phototherapeutic strategy displays great therapeutic potential in treating the formidable clinical problems caused by MRSA biofilms and the accompanying inflammation.