bluuebunny/crossref_metadata_2025 huggingface dataset:
Addition of spherical‐style packing improves the production of conidia by Metarhizium robertsii in packed column bioreactors
Authors: Méndez‐González Fernando , Figueroa‐Montero Arturo , Saucedo‐Castañeda Gerardo , Loera Octavio , Favela‐Torres Ernesto
Published: November 2021

BACKGROUND

Conidia from Metarhizium are part of the commercial formulations used worldwide for insect pest control. Among the alternatives proposed to improve conidia production, the use of packed column bioreactors allows controlled processes with higher levels of production and productivity than those obtained with the traditional process in plastic bags. However, problems associated with overheating, low CO2 removal, and inadequate oxygen supply in packed columns limit the scale‐up and operation at an industrial scale.

RESULTS

Packed densities, up to 1.5 times higher than those obtained in lab‐scale column bioreactors, negatively affected growth and conidia production by Metarhizium robertsii (ENCB‐MG‐81). Therefore, a spherical‐style packing was added to decrease packed density and improve the culture conditions in packed column bioreactors. The addition of spherical‐style packing reduced the axial temperature gradient (up to 50%), increased the maximum CO2 production rate and the total CO2 production (up to 2.5 times), and enhanced the volumetric conidia productivity in packed column bioreactors from 5.28 ± 1.36 to 6.77 ± 0.89 × 108 conidia cm−3.

CONCLUSION

The use of spherical‐style packing within the culture bed in column bioreactors improves the production of conidia by Metarhizium robertsii, as well as the gas exchange and heat removal from the bed. © 2021 Society of Chemical Industry (SCI).
Pretreatment with high oxygen controlled atmosphere enhanced fresh‐cut white mushroom (Agaricus bisporus) quality via activating wounding stress defenses
Authors: Wang Liang , Han Minjie , Cui Yingjun , Wang Xiangyou , Shan Xinhe , Wang Chongqing
Published: November 2021

BACKGROUND

High oxygen treatment has been proven to be effective in fresh‐cut white mushroom preservation, however, the preservation effect and possible mechanisms in high oxygen controlled atmosphere pretreatment (HOCAP) on wounding stress are incompletely understood.

RESULTS

In this study, based on the time chosen of HOCAP research, whole white mushrooms treated with 3 h HOCAP (80% O2 + 20% CO2) and the wounding resistant responses of their slices were mainly investigated through phenylpropane pathway, reactive oxygen species (ROS) scavenging system, and ascorbate–glutathione (AsA–GSH) cycle. Results showed that 3 h HOCAP can induce the production of hydrogen peroxide (H2O2) and superoxide anion (O2−•) in the early stage, as well as the NADPH oxidase activity. Enzymes and endogenous antioxidants involved in ROS scavenging were enhanced by HOCAP during the whole storage. Besides, HOCAP maintained high level of phenylalanine ammonia‐lyase (PAL) activity, enhanced the content of total phenolic and lignin, accelerated the AsA–GSH cycle.

CONCLUSION

The results demonstrated that HOCAP induced defense responses by increasing the ROS in the early stage which stimulated the activities of ROS scavenging enzymes, along with the capability of increasing for wounding stress defense and resistance. This study provides a theoretical pretreatment technology for fresh‐cut white mushroom preservation. © 2021 Society of Chemical Industry.
Polymer Nanoparticle‐Mediated Delivery of Oxidized Tumor Lysate‐Based Cancer Vaccines
Authors: Berti Cristiana , Graciotti Michele , Boarino Alice , Yakkala Chakradhar , Kandalaft Lana E. , Klok Harm‐Anton
Published: November 2021

Cancer vaccination is a powerful strategy to combat cancer. A very attractive approach to prime the immune system against cancer cells involves the use of tumor lysate as antigen source. The immunogenicity of tumor lysate can be further enhanced by treatment with hypochlorous acid. This study explores poly(lactic‐co‐glycolic acid) (PLGA) nanoparticles to enhance the delivery of oxidized tumor lysate to dendritic cells. Using human donor‐derived dendritic cells, it is found that the use of PLGA nanoparticles enhances antigen uptake and dendritic cell maturation, as compared to the use of the free tumor lysate. The ability of the activated dendritic cells to stimulate autologous peripheral blood mononuclear cells (PBMCs) is assessed in vitro by coculturing PBMCs with A375 melanoma cells. Live cell imaging analysis of this experiment highlights the potential of nanoparticle‐mediated dendritic‐cell‐based vaccination approaches. Finally, the efficacy of the PLGA nanoparticle formulation is evaluated in vivo in a therapeutic vaccination study using B16F10 tumor‐bearing C57BL/6J mice. Animals that are challenged with the polymer nanoparticle‐based oxidized tumor lysate formulation survive for up to 50 days, in contrast to a maximum of 41 days for the group that receives the corresponding free oxidized tumor lysate‐based vaccine.
Lightweight and Mechanically Robust EPDM Foams for High Thermal Insulation and Moderate Ablative Resistance Via Constructing Cellular Char Layer
Authors: Qu Hongjian , Hui Kun , Bian Cheng , Guan Yiwen , Li Hongyan , Luan Tao , Yan Ning
Published: November 2021

Ethylene propylene diene monomer (EPDM) foams have received considerable attention owing to their low weight, low thermal conductivity, and mechanical flexibility. However, their poor ablative resistance and low thermal stability make their use in severe conditions, such as the combustion chamber of a solid rocket motor, difficult. In this study, EPDM foams reinforced with aramid fibers (AFs) and carbon fibers (CFs) are prepared through a hot‐pressing‐induced foaming process. The effects of the fibers on the cellular structure, thermal stability, and mechanical, ablating, and insulating properties of the EPDM foams are investigated. The results show that the addition of CFs enhanced the thermal stability and mechanical properties of the EPDM foams, whereas the use of AFs lowered the thermal conductivity and ablation rate. In particular, when 2.5 phr (parts per hundred parts of rubber) AF and 2.5 phr CF are added, the linear ablation rate tested using oxyacetylene is 0.33 mm s−1, and the back‐face temperature is 53 °C, revealing a good balance in terms of ablative resistance and thermal insulation. Thus, the hybrid‐fiber‐reinforced EPDM foams possess several advantages, such as low weight, good thermal insulation, ablative resistance, and mechanical robustness, suggesting considerable potential for application in the aerospace industry.
Collisional experiences with Dr. Pietro Traldi and the incredible group in Padova
Authors: March Raymond Evans
Published: November 2021

Two Early Classic period (ca. 250–600 CE) Maya carved, greenstone jade pendants, Specimens A and B, were recovered from the Pacbitun site in Belize in 1987. The specimens were visually similar and may have been cut from a common jade piece. Mass spectrometry was considered as a technique that could possibly be used to explore the similarity of the specimens. However, at that time, neither electrospray ionization nor matrix‐assisted laser desorption/ionization (MALDI) had been discovered; furthermore, only elemental analysis had been carried out with jade samples and there were no accounts of polyatomic ions being produced from jade. The discoverer of the greenstone jade pendants, a faculty member in Anthropology at Trent University, sought the assistance of the author of this piece but no immediate progress was accomplished. About 7 years after discovery of the greenstone jade pendants, this author was invited to spend a short sabbatical leave in the laboratory of Dr. Pietro Traldi in Padova, Italy. While this invitation was attractive for several reasons, the principal attraction was Dr. Traldi's new, and mysterious acquisition of MALDI instrumentation. There was, perhaps, a single iota of reason that appeared to suggest unusual assistance of a matrix in liberating polyatomic ions from jade using laser irradiation. This account is of a very interesting sojourn with Dr. Traldi and members of his laboratory which did not lead to any immediate understanding of MALDI; however, the belief was constant for the next 20 years after which some progress was made in the exploration of the structure of jade.
Imbalanced Folate and Vitamin B12 in the Third Trimester of Pregnancy and its Association with Birthweight and Child Growth up to 2 Years
Authors: Obeid Rima , Eussen Simone J.P.M. , Mommers Monique , Smits Luc , Thijs Carel
Published: November 2021

Scope

Folic acid supplementation during pregnancy may lead to an imbalance when vitamin B12 intake is low (folate trap) and may affect child's growth.

Methods

The authors study the association between third trimester maternal intakes of folate and B12 and birthweight and postnatal growth of 2632 infants from the KOALA Birth Cohort Study. Plasma vitamin biomarkers are measured in 1219 women.

Results

Imbalanced total intakes (folate > 430 µg day−1 combined with B12 < 5.5 µg day−1) are not associated with birthweight [β adj (95% CI) = –14.87 (–68.87, 39.13)] compared with high intakes of both. Imbalanced intake is associated with a lower z score of weight at 1–2 years [β adj = –0.14 (–0.25, –0.03)]. Having red blood cell folate > 745 nmol L−1 and plasma B12 < 172 pmol L−1 is not associated with birthweight [β adj = –7.10 (–97.90, 83.71) g]. Maternal dietary B12 intake [β adj = –9.5 (–15.6, –3.3)] and plasma methylmalonic acid [β adj = 234 (43, 426)] are associated with birthweight.

Conclusion

Low maternal dietary B12 intake and elevated methylmalonic acid rather than imbalanced vitamins are associated with higher birthweight, suggesting that low maternal B12 can predispose the infants for later obesity.
A compact low‐cost dual‐band bandpass filter with enhanced suppression using substrate integrates suspended line technology
Authors: Zhang Yudan , Ma Kaixue , Chen Xiong
Published: November 2021

A compact dual‐band bandpass filter based on the substrate integrates suspended line platform is proposed in this letter. The design is implemented using low‐cost FR‐4 material, while the loss can be reduced by 3D metal connections with substrate cutout. 0.97 dB/1.6 dB improvement of insertion loss is achieved and verified at 3.45 GHz/4.9 GHz. By paralleling quarter wavelength step impedance resonators with different operating frequencies, two paths formed between source and load. Both bandwidth and location of transmission zeros can be adjusted independently. Two stubs are added working not only as feed structure but also as a stop band resonator, which can provide 20 dB out‐of‐band suppression up to 4.4f0. The obtained performances are good enough to compare with the state of art, though very low‐cost FR‐4 materials are used.
Research on W‐band high‐gain magneto‐electric dipole antenna based on double‐sided gap waveguide
Authors: Wang Hao , Cao Jianyin , Ye Zhongtian , Quan Yu , Tao Shifei
Published: November 2021

In this paper, a W‐band magneto‐electric (ME) dipole antenna fed by double‐sided gap waveguide (DSGWG) feeding network is presented. The ME dipole antenna element is designed based on the end‐fire DSGWG and extended ridge with pins. The end‐fire open slot of DSGWG radiate as a magnetic dipole, and the metallic pins in extended ridge radiate as electric dipoles. Taking advantage of this DSGWG structure, the antenna element achieves with high gain and wide bandwidth performances. The antenna element is fabricated and measured with an impedance matching bandwidth of 85–110 GHz for |S11| < −10 dB, and maximum realized gain of 9.2 dBi. A four‐way feeding network based on the DSGWG is designed and connected directly to the ME dipole antennas. The antenna array with ease integration and fabrication properties is designed to validate the performance of antenna elements. The measured average realized gain of the antenna array reaches up to 15.3 dBi over the bandwidth of 88–110 GHz.
Hydraulic fracturing of weak rock during waterflooding
Authors: Detournay Emmanuel , Hakobyan Yera
Published: November 2021

This paper describes a KGD‐type model of a hydraulic fracture created by injecting fluid in weak, poorly consolidated rocks. The model is based on the key assumption that the hydraulic fracture is propagating within a domain where the hydraulic fields are quasi‐stationary. By further assuming a negligible toughness, the fracture is shown to grow as a square root of time. The asymptotic fracture propagation regimes at small and large time are constructed and the transient solution is computed by solving a nonlinear system of algebraic equations formulated in terms of the fracture aperture. At early time, the fracture is hydraulically invisible and the injection pressure increases with time as , while at late time, leak‐off from the borehole is negligible and the injection pressure decreases as . According to this model, the peak injection pressure observed when injecting fluid in weak, poorly consolidated rocks should not be interpreted as indicating a breakdown of the formation, but rather as marking the transition between two asymptotic flow regimes. The timescale that legislates the transition between the small and large time asymptotic regimes is shown to be a strongly nonlinear function of a dimensionless injection rate.
In vivo functional validation of the V402L voltage gated sodium channel mutation in the malaria vector An. gambiae
Authors: Williams Jessica , Cowlishaw Ruth , Sanou Antoine , Ranson Hilary , Grigoraki Linda
Published: November 2021

BACKGROUND

Pyrethroids are the most widely used insecticides for the control of malaria transmitting Anopheles gambiae mosquitoes and rapid increase in resistance to this insecticide class is of major concern. Pyrethroids target the Voltage Gated Sodium Channels (VGSCs), that have a key role in the normal function of the mosquitoes' nervous system. VGSC mutations L995F and L995S have long been associated with pyrethroid resistance and screening for their presence is routine in insecticide resistance management programs. Recently, a VGSC haplotype containing two amino acid substitutions associated with resistance in other species, V402L and I1527T, was identified. These two VGSC mutations are found in tight linkage and are mutually exclusive to the classical L995F/S mutations.

RESULTS

We identify the presence of the V402L‐I1527T haplotype in resistant An. coluzzii colonized strains and in field populations from Burkina Faso, at frequencies higher than previously reported; in some cases almost reaching fixation. Functional validation of V402L in insecticide resistance using a CRISPR/Cas9 genome modified line showed that it confers reduced mortality after exposure to all tested pyrethroids and DDT, but at lower levels compared to L995F. In contrast to L995F however, no fitness costs were identified for mosquitoes carrying V402L under laboratory conditions.

CONCLUSION

The V402L substitution confers pyrethroid resistance in An. gambiae in the absence of any other VGSC substitution and/or alternative resistance mechanisms. The lower fitness cost associated with this kdr mutation may provide a selective advantage over the classical kdr in some settings and genotyping at this locus should be added in the list of resistant alleles for routine screening.
Stability evaluation in process mean using Bayesian statistics and information theory
Authors: Takemoto Yasuhiko , Arizono Ikuo
Published: November 2021

At the start of new operation, a production process is commonly unstable. Then, a process condition is into being stable gradually over time. For the purpose of shifting to mass production, the stability in a process should be evaluated. This paper proposes a method of evaluating the process stability based on Bayesian statistics and information theory. In Bayesian statistics, the knowledge for a process is renewed by deriving posterior distribution based on current prior distribution and observations. Here, equivalency between prior and posterior distributions could be considered to be a criterion for the stability in a process. It is needed to define difference between prior and posterior distributions in order to evaluate the equivalency between prior and posterior distributions. We first formulate the relation between the prior distribution and the posterior distribution for process mean using Bayesian statistics. Secondly, we evaluate the difference between the both distributions based on Kullback‐Leibler (K‐L) divergence in information theory. Finally, some numerical examples in the method of evaluating the stability in process mean are illustrated. Also, we discuss about a decision rule for the stability in process mean through the numerical investigation.
The impact of the complexing agent on the sensitivity of collision‐induced dissociation spectra to fatty acid position for a set of XYZ‐type triglycerides
Authors: Gazlay William , Evans Jason J.
Published: November 2021

Rationale

The development of an automated platform for the positional analysis of triglycerides (TAGs) based on electrospray ionization tandem mass spectrometry (ESI‐MS/MS) continues to be pursued. This work evaluates the positional sensitivities of the collision‐induced dissociation (CID) spectra of a representative set of XYZ triglycerides using sodium, lithium, and ammonium salts as complexing agents.

Methods

A set of triglycerides were synthesized and analyzed via ESI‐MS/MS using an ion trap mass spectrometer. Using three different complexing agents, the product ion spectra of the corresponding precursor ions for twelve XYZ TAGs were collected, where X, Y, and Z represent C16:0, C18:1(c‐9), C18:2(cc‐9,12), and C20:4(cccc‐5,8,11,14) fatty acid chains. These data were then used to prepare ternary plots for four positional isomer systems to evaluate the positional sensitivity differences among the three different complexing agents.

Results

The positional sensitivities for each of the four positional isomer systems were robust for the sodium and lithium adducts. The CID data for the sodium and lithium TAGs demonstrated an unfavorable loss of the fatty acid in the center position and showed a higher sensitivity to fatty acid position, when compared with the CID data for ammonium adducts, especially for the arachidonic acid containing triglycerides.

Conclusions

The data shows that that the relative abundances of the DAG product ions for the XYZ‐type TAGs when using sodium and lithium complexing agent adducts are sensitive to fatty acid position and are consistent for the diverse array of TAGs studied in this work. This suggests that using sodium or lithium as the complexing agent may be advantageous for the development of an automated platform for the positional analysis of complex TAG mixtures based on ESI‐MS/MS.
Competing on freemium: Digital competition with network effects
Authors: Boudreau Kevin J. , Jeppesen Lars Bo , Miric Milan
Published: November 2021

Research Summary

“Freemium” product strategies—where a free basic version of a product is offered alongside a full “premium” paid version—are often used by companies to attempt to increase the size of their user base and benefit from network effects. However, there is limited empirical evidence of how using freemium strategies impacts firm revenues. We empirically investigate how the strengthening of network effects on the Apple App Store influenced product sales of firms using freemium strategies, contrasting the impacts on both market leaders and followers. We find that stronger network effects did not on their own lead to greater revenues for market leaders with respect to followers. However, in settings where freemium strategies were used, network effects greatly amplified the advantage of leaders over followers.

Managerial Summary

Freemium strategies are increasingly common as a way for firms to increase the number of users and benefit from network effects. However, there has not been much empirical investigation in this regard, particularly in cases where products using freemium strategies face competition. In this article, we investigate how a policy by Apple on the App Store that led to stronger network effects, impacted the performance of market leaders and followers depending on whether they used freemium or not. We find that it led to an increase in revenues of leaders over followers (effectively, market dominance) but only when freemium strategies were used. The analysis demonstrates an interplay the between business model and network effects. In addition, it shows how stronger network effects and freemium strategies only benefitted market leaders in our setting.
Predicting Perovskite Bandgap and Solar Cell Performance with Machine Learning
Authors: Gok Elif Ceren , Yildirim Murat Onur , Haris Muhammed P. U. , Eren Esin , Pegu Meenakshi , Hemasiri Naveen Harindu , Huang Peng , Kazim Samrana , Uygun Oksuz Aysegul , Ahmad Shahzada
Published: November 2021

Perovskites as semiconductors are of profound interest and arguably, the investigation on the distinctive perovskite composition is paramount to fabricate efficient devices and solar cells. The role of anion and cations and their impact on optoelectronic and photovoltaic properties is probed. A machine learning (ML) approach to predict the bandgap and power conversion efficiency (PCE) using eight different perovskites compositions is reported. The predicted solar cell parameters validate the experimental data. The adopted Random forest model presents a good match with high R2 scores of >0.99 and >0.82 for predicted absorption and J−V datasets, respectively, and show minimal error rates with a precise prediction of bandgap and PCEs. The results suggest that the ML technique is an innovative approach to aid the preparation of the perovskite and can accelerate the commercial aspects of perovskite solar cells without fabricating working devices and minimize the fabrication steps and save cost.
Rethinking agency—The 2022 agenda for the systems community
Authors: Klein Louis , Buckle Pamela , Nguyen Nam , Preiser Rika , Ison Ray
Published: November 2021

Five clusters of concern arising from IFSR‐facilitated conversations with its organisational members are used to invite the broader systems community to rethink agency. It is argued that by addressing the cluster elements, potential will be co‐created for the systems community as a whole to help citizens venture beyond failing responses to the global problematique and the Anthropocene‐creating thinking in which we humans are trapped. The five clusters are as follows:

Exploring the in‐between: Growing a shared understanding is going beyond a competition of ideas or a clash of concepts. It is a joint exploration of the unknown in‐between.

Including the excluded: Systems research happens in open research ecosystems, not in disciplinary silos. It is transdisciplinary and constitutes a global discourse.

Living questions: Questions shape paradigms. Transcending paradigms starts from allowing the questions to have their own life, to grow and to dissolve, to improve and to transform.

Going beyond systems literacy: Learning to speak systems is one thing, proficiency in systems thinking, systems doing and systems being another. There is a difference between knowing and understanding that we may address as systems wisdom.

Rethinking agency: Agency goes from ego to eco, from me to we. Yet, it is not an either–or; it is ego and eco, me and we. To understand agency, we need to understand the ‘and’.
Reversal of stem cell‐derived hypertrophic adipocytes mediated by photobiomodulation (1064 nm)
Authors: McColloch Andrew , Liu Hanli , Cho Michael
Published: November 2021

Hypertrophic adipocytes have been implicated in the progression of obesity‐induced complications. These enlarged fat cells cause release of free fatty acids and inflammatory cytokines, promote hypoxia and fibrosis and limit insulin sensitivity. Photobiomodulation (PBM), or the influence of light on biological tissues, has previously been demonstrated to reduce lipid accumulation in stem cells undergoing adipogenesis. Here, we characterize the effect of PBM on an in vitro hypertrophic obesity model and its influence on reduction of lipids and restoration to normal adipocyte function. Adipose‐derived stem cells were induced to hypertrophy with the addition of palmitic acid (PA) and was confirmed with fluorescent imaging of lipid content, and functional changes such as glucose uptake. Glucose transport into the cell was diminished and the expression of glucose transporter GLUT4 was downregulated. PBM‐treated hypertrophic cells (1064 nm and 17.6 J/cm2 every day for 7 days following addition of PA) decreased the lipid levels in hypertrophic adipocytes, restored the GLUT4 protein expression and enhanced glucose transport. Taken together, PBM is shown capable of restoring the cellular morphology and function of hypertrophic cells. This could have important clinical implication for the development of laser‐based potential therapeutic treatment of complications due to metabolic syndrome.
Accelerating wheat breeding for end‐use quality through association mapping and multivariate genomic prediction
Authors: Zhang‐Biehn Shichen , Fritz Allan K. , Zhang Guorong , Evers Byron , Regan Rebecca , Poland Jesse
Published: November 2021

In hard‐winter wheat (Triticum aestivum L.) breeding, the evaluation of end‐use quality is expensive and time‐consuming, being relegated to the final stages of the breeding program after selection for many traits including disease resistance, agronomic performance, and grain yield. In this study, our objectives were to identify genetic variants underlying baking quality traits through genome‐wide association study (GWAS) and develop improved genomic selection (GS) models for the quality traits in hard‐winter wheat. Advanced breeding lines (n = 462) from 2015–2017 were genotyped using genotyping‐by‐sequencing (GBS) and evaluated for baking quality. Significant associations were detected for mixograph mixing time and bake mixing time, most of which were within or in tight linkage to glutenin and gliadin loci and could be suitable for marker‐assisted breeding. Candidate genes for newly associated loci are phosphate‐dependent decarboxylase and lipid transfer protein genes, which are believed to affect nitrogen metabolism and dough development, respectively. The use of GS can both shorten the breeding cycle time and significantly increase the number of lines that could be selected for quality traits, thus we evaluated various GS models for end‐use quality traits. As a baseline, univariate GS models had 0.25–0.55 prediction accuracy in cross‐validation and from 0 to 0.41 in forward prediction. By including secondary traits as additional predictor variables (univariate GS with covariates) or correlated response variables (multivariate GS), the prediction accuracies were increased relative to the univariate model using only genomic information. The improved genomic prediction models have great potential to further accelerate wheat breeding for end‐use quality.
Medium-term and peri-lockdown course of psychosocial burden during the ongoing COVID-19 pandemic: a longitudinal study on patients with pre-existing mental disorders
Authors: Bartels Claudia , Hessmann Philipp , Schmidt Ulrike , Vogelgsang Jonathan , Ruhleder Mirjana , Kratzenberg Alexander , Treptow Marit , Reh-Bergen Thorgund , Abdel-Hamid Mona , Heß Luisa , Meiser Miriam , Signerski-Krieger Jörg , Radenbach Katrin , Trost Sarah , Schott Björn H. , Wiltfang Jens , Wolff-Menzler Claus , Belz Michael
Published: November 2021

While the COVID-19 pandemic continues, patients with pre-existing mental disorders are increasingly recognized as a risk group for adverse outcomes. However, data are conflicting and cover only short time spans so far. Here, we investigate the medium-term and peri-lockdown-related changes of mental health outcomes in such patients in a longitudinal study. A cohort of 159 patients comprising all major mental disorders (ICD-10 F0-F9) were interviewed twice with the Goettingen psychosocial Burden and Symptom Inventory (Goe-BSI) to evaluate psychosocial burden, psychiatric symptoms and resilience at the end of the first (April/May 2020) and the second lockdown in Germany (November/December 2020). For the primary outcome “psychosocial burden” ratings also comprised retrospective pre-pandemic (early 2020) and very early states during the pandemic (March 2020). For all diagnostic groups, psychosocial burden varied significantly over time (p < 0.001) with an increase from the pre-pandemic to the initial phase (p < 0.001), followed by a steady decrease across both lockdowns, normalizing in November/December 2020. Female gender, high adjustment disorder symptom load at baseline and psychiatric comorbidities were risk factors for higher levels and an unfavorable course of psychosocial burden. Most psychiatric symptoms changed minimally, while resilience decreased over time (p = 0.044 and p = 0.037). The longitudinal course of psychosocial burden indicates an initial stress response, followed by a return to pre-pandemic levels even under recurrent lockdown conditions, mimicking symptoms of an adjustment disorder. Strategies for proactive, specific and continuous treatment have to address resilience capacities before their depletion in the pandemic aftermath, especially for patients with additional risk factors.
Great occipital nerve long-acting steroid injections in cluster headache therapy: an observational prospective study
Authors: Merli Elena , Asioli Gian Maria , Favoni Valentina , Zenesini Corrado , Mascarella Davide , Sartori Alex , Cortelli Pietro , Cevoli Sabina , Pierangeli Giulia
Published: November 2021

Background

Injections targeting the occipital nerve are used to reduce headache attacks and abort cluster bouts in cluster headache patients. There is no widely accepted agreement over the optimal technique of injection, type and doses of steroids and/or anesthetics to use, as well as injection regimens. The aim of this study was to verify the effectiveness and safety of greater occipital nerve long-acting steroid injections in the management of episodic and chronic cluster headache.

Methods

We conducted a prospective observational cohort study on episodic (ECH) and chronic cluster headache patients (CCH). ECH were included in the study at the beginning of a cluster period. Three injections with 60 mg methylprednisolone were performed on alternate days. We registered the frequency and intensity of attacks three days before and 3, 7 and 30 days after the treatment, the latency of cluster relapse, adverse events, scores evaluating anxiety (Zung scale), depression (Beck’s Depression Scale) and quality of life (Disability Assessment Schedule II, 12-Item Self-Administered Version). Primary outcome was the interruption of the cluster after the three injections. Responders conducted a follow-up period of 12 months.

Results

We enrolled 60 patients, 47 with ECH and 13 with CCH. We observed a complete response in 47.8% (22/46) of episodic and 33.3% (4/12) of chronic patients. Moreover, a partial response (reduction of at least 50% of attacks) was obtained in further 10.8% (5/46) of episodic and in 33.3% (4/12) of chronic patients at 1 month. Median pain-free period was of 3 months for CCH responders. Only mild adverse events were reported in 38.3% (23/58) cases.

Conclusions

We suggest three greater occipital nerve injections of 60 mg methylprednisolone on alternate days as useful therapy in episodic and chronic cluster headache. This leads to a long pain-free period in chronic forms. Adverse effects are mild and support its use as first choice.

Trial registration

The study was inserted in AIFA observational studies register.
Relapse activity in the chronic phase of anti-myelin-oligodendrocyte glycoprotein antibody-associated disease
Authors: Akaishi Tetsuya , Misu Tatsuro , Fujihara Kazuo , Takahashi Toshiyuki , Takai Yoshiki , Nishiyama Shuhei , Kaneko Kimihiko , Fujimori Juichi , Ishii Tadashi , Aoki Masashi , Nakashima Ichiro
Published: November 2021

Objective

The patterns of relapse and relapse-prevention strategies for anti-myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) are not completely investigated. We compared the patterns of relapse in later stages of MOGAD with those of anti-aquaporin-4 antibody (AQP4-Ab)-positive neuromyelitis optica spectrum disorder (NMOSD).

Methods

In this observational, comparative cohort study, 66 patients with MOGAD and 90 with AQP4-Ab-positive NMOSD were enrolled. We compared the patterns of relapse and annualized relapse rates (ARRs) in the first 10 years from disease onset, stratified by relapse-prevention treatments.

Results

Approximately 50% of the patients with MOGAD experienced relapses in the first 10 years. Among those not undergoing relapse-prevention treatments, ARRs in the first 5 years were slightly lower in MOGAD patients than in AQP4-Ab-positive NMOSD patients (MOGAD vs. AQP4-Ab NMOSD: 0.19 vs. 0.30; p = 0.0753). After 5 years, the ARR decreased in MOGAD patients (MOGAD vs. AQP4-Ab NMOSD: 0.05 vs. 0.34; p = 0.0001), with a 72% reduction from the first 5 years (p = 0.0090). Eight (61.5%) of the 13 MOGAD patients with more than 10-year follow-up from disease onset showed relapse 10 years after onset. Clustering in the timing and phenotype of attacks was observed in both disease patients. The effectiveness of long-term low-dose oral PSL for relapse prevention in patients with MOGAD has not been determined.

Conclusions

The relapse risk in patients with MOGAD is generally lower than that in patients with AQP4-Ab-positive NMOSD, especially 5 years after onset. Meanwhile, relapses later than 10 years from onset are not rare in both diseases.
On the interrelation of equilibrium positions and work of friction forces on brake squeal
Authors: Koch Sebastian , Gödecker Holger , von Wagner Utz
Published: November 2021

Brake noise, in particular brake squeal, is a permanent topic both in industry and academia since decades. Nonlinearities play a decisive role for this phenomenon. One nonlinear effect widely ignored so far is that the brake can engage multiple equilibrium positions with severe consequences on the noise behavior. In fact in an automotive disk brake, the essential elements carrier, caliper and pad are elastically coupled with each other and their behavior is nonlinear that multiple equilibrium positions are possible. The engaged equilibrium position depends, for example, on the initial conditions, external disturbances, and the transient application of the brake pressure, and in consequence configurations with or without self-exciting characteristics of the friction forces result. Obviously, a self-exciting characteristic of the friction force is a necessary precondition for the occurrence of squeal. The authors recently published some corresponding results (Koch et al. FU Mech Eng, 2021. https://doi.org/10.22190/FUME210106020K) demonstrating that for same operating parameters with respect to brake pressure (i.e., brake torque), rotational speed and temperature the engaged equilibrium position has decisive influence whether squeal occurs or not. While in Koch et al. (2021) it has just been detected whether there is squeal or not, the excitation characteristic of the friction forces becomes, beside the engaged equilibrium position, the additional focus in the present paper. Therefore, a work criterion already successfully applied in earlier publications for squeal tendency is considered. For the experimental application of the work criterion, accelerometers have to be mounted. The accelerometers’ location to be applied can be determined in the chosen setup by the camera system anyway necessary for the measurement of the engaged equilibrium position. With this refined setup, it is possible to specify the states squeal, close to squeal and far from squeal. The test series again demonstrate the decisive influence of the engaged equilibrium position (for constant operation parameters) on the occurrence of the respective state. These findings can have consequences for simulations (consideration of multiple equilibrium positions in models and respective linearization with consequences on system’s eigenvalues), but also for the design (avoidance of equilibrium positions suspicious for squeal) and experimental setups (determination of special positions) of brakes.
An electromechanically coupled beam model for dielectric elastomer actuators
Authors: Huang Dengpeng , Leyendecker Sigrid
Published: November 2021

In this work, the Cosserat formulation of geometrically exact beam dynamics is extended by adding the electric potential as an additional degree of freedom to account for the electromechanical coupling in the dielectric elastomer actuators. To be able to generate complex beam deformations via dielectric actuator, a linear distribution of electric potential on the beam cross section is proposed. Based on this electric potential, the electric field and the strain-like electrical variable are defined for the beam, where the strain-like electrical variable is work-conjugated to the electric displacement. The electromechanically coupled strain energy for the beam is derived consistently from continuum electromechanics, which leads to the direct application of the material models in the continuum to the beam model. The electromechanically coupled problem in beam dynamics is first spatially semidiscretized by 1D finite elements and then solved via variational time integration. By applying different electrical boundary conditions, different deformations of the beam are obtained in the numerical examples, including contraction, shear, bending and torsion. The damping effect induced by the viscosity as well as the total energy of the beam are evaluated. The deformations of the electromechanically coupled beam model are compared with the results of the 3D finite element model, where a good agreement of the deformations in the beam model and that in the 3D finite element model is observed. However, less degrees of freedom are required to resolve the complex deformations in the beam model.
Safety analysis and complications of condylar screws in a single-surgeon series of 250 occipitocervical fusions
Authors: Tam Sharon Ka Po. , Bolognese Paolo A. , Kula Roger W. , Brodbelt Andrew , Foroughi Mansoor , Avshalumov Marat , Mugutso Denmark , Ruhoy Ilene
Published: November 2021

Objective

Condylar screw fixation is a rescue technique and an alternative to the conventional configuration of occipitocervical fusion. Condylar screws are utilized when previous surgical bone removal along the supraocciput has occurred which makes anchoring of a traditional barplate technically difficult or impossible. However, the challenging dissection of C0-1 necessary for condylar screw fixation and the concerns about possible complications have, thus far, prevented the acquisition of large surgical series utilizing occipital condylar screws. In the largest case series to date, this paper aims to evaluate the safety profile and complications of condylar screw fixation for occipitocervical fusion.

Methods

A retrospective safety and complication-based analysis of occipitocervical fusion via condylar screws fixation was performed.

Results

A total of 250 patients underwent occipitocervical fusions using 500 condylar screws between September 2012 and September 2018. No condylar screw pullouts, or vertebral artery impingements were observed in this series. The sacrifice of condylar veins during the dissection at C0-1 did not cause any venous stroke. Hypotrophic condyles were found in 36.4% (91 of the 250) cases and did not prevent the insertion of condylar screws. Two transient hypoglossal deficits occurred at the beginning of this surgical series and were followed by recovery a few months later. Corrective strategies were effective in preventing further hypoglossal injuries.

Conclusions

This surgical series suggests that the use of condylar screws fixation is a relatively safe and reliable option for OC fusion in both adult and pediatric patients. Methodical dissection of anatomical landmarks, intraoperative imaging, and neurophysiologic monitoring allowed the safe execution of the largest series of condylar screws reported to date. Separate contributions will follow in the future to provide details about the long-term clinical outcome of this series.
An investigation into the cutting efficiency of a novel degradable glass as an alternative to alumina powder in air abrasion cutting of enamel
Authors: Kotsanidou Zoi , Zou Lifong , Hill Robert , Janicki Tomasz
Published: November 2021

Objectives

To develop and test the cutting efficiency of a novel degradable glass as an alternative media to alumina powder for air abrasion.

Materials and methods

A zinc-based glass (QMZK2) was designed, produced, and evaluated with a multi-modality imaging analysis. The glass dissolution study was carried out in three acids, using ICP-OES (inductively coupled plasma optical emission spectroscopy) at 5 different time points: 2.5, 5, 10, 60, and 240 min. The cutting efficiency of both materials was tested under the same parameters on slabs of elephant enamel. A stained fissure of a molar tooth was air abraded with the glass and evaluated with X-ray micro-tomography before and after air abrasion.

Results

The particle size distribution of the glass was similar to that of alumina 53 µm but with a slightly greater dispersion of particle size. The shape of the particles was angular, appropriate for cutting purposes. The dissolution study showed that the glass dissolved rapidly in acidic conditions at all time points. Between the two variables, pressure and powder flow, pressure was found to influence the cutting speed to a greater extent than powder flow.

Conclusions

Alumina powder was found to perform significantly better in 4 of the 9 conditions tested on elephant enamel, QMZK2 in one, and no significant differences were found for the rest of the 4 conditions. The QMZK2 seems to offer promising results as an alternative material to alumina.

Clinical relevance.

QMZK2 glass has the potential for replacing aluminum oxide as a degradable material in air abrasion technology.
Low-rank tensor approximation of singularly perturbed boundary value problems in one dimension
Authors: Marcati Carlo , Rakhuba Maxim , Ulander Johan E. M.
Published: November 2021

We derive rank bounds on the quantized tensor train (QTT) compressed approximation of singularly perturbed reaction diffusion boundary value problems in one dimension. Specifically, we show that, independently of the scale of the singular perturbation parameter, a numerical solution with accuracy $$0<\varepsilon <1$$

0
<
ε
<
1

can be represented in the QTT format with a number of parameters that depends only polylogarithmically on $$\varepsilon $$
ε
. In other words, QTT-compressed solutions converge exponentially fast to the exact solution, with respect to a root of the number of parameters. We also verify the rank bound estimates numerically and overcome known stability issues of the QTT-based solution of partial differential equations (PDEs) by adapting a preconditioning strategy to obtain stable schemes at all scales. We find, therefore, that the QTT-based strategy is a rapidly converging algorithm for the solution of singularly perturbed PDEs, which does not require prior knowledge on the scale of the singular perturbation and on the shape of the boundary layers.
Molecular and cellular mechanisms controlling integrin-mediated cell adhesion and tumor progression in ovarian cancer metastasis: a review
Authors: Dhaliwal Dolly , Shepherd Trevor G.
Published: November 2021

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy in the developed world. EOC metastasis is unique since malignant cells detach directly from the primary tumor site into the abdominal fluid and form multicellular aggregates, called spheroids, that possess enhanced survival mechanisms while in suspension. As such, altered cell adhesion properties are paramount to EOC metastasis with cell detachment from the primary tumor, dissemination as spheroids, and reattachment to peritoneal surfaces for secondary tumor formation. The ability for EOC cells to establish and maintain cell–cell contacts in spheroids is critical for cell survival in suspension. Integrins are a family of cell adhesion receptors that play a crucial role in cell–cell and cell-extracellular matrix interactions. These glycoprotein receptors regulate diverse functions in tumor cells and are implicated in multiple steps of cancer progression. Altered integrin expression is detected in numerous carcinomas, where they play a role in cell migration, invasion, and anchorage-independent survival. Like that observed for other carcinomas, epithelial-mesenchymal transition (EMT) occurs during metastasis and integrins can function in this process as well. Herein, we provide a review of the evidence for integrin-mediated cell adhesion mechanisms impacting steps of EOC metastasis. Taken together, targeting integrin function may represent a potential therapeutic strategy to inhibit progression of advanced EOC.
A Method to Pre-compile Numerical Integrals When Solving Stochastic Dynamic Problems
Authors: Arapakis Karolos
Published: November 2021

We show how the interpolation step of numerical integration can be pre-compiled in partial equilibrium stochastic dynamic problems. We display the pre-compilation’s sufficient conditions and document its speed gains using a consumption-savings model with a discrete labour choice, wage uncertainty and stochastic non-labour income.
Real-time bidding campaigns optimization using user profile settings
Authors: Miralles-Pechuán Luis , Qureshi M. Atif , Namee Brian Mac
Published: November 2021

Real-Time bidding is nowadays one of the most promising systems in the online advertising ecosystem. In the presented study, the performance of RTB campaigns is improved by optimising the parameters of the users’ profiles and the publishers’ websites. Most studies about optimising RTB campaigns are focused on the bidding strategy; estimating the best value for each bid. However, our research is focused on optimising RTB campaigns by finding out configurations that maximise both the number of impressions and the average profitability of the visits. An online campaign configuration generally consists of a set of parameters along with their values such as {Browser = “Chrome”, Country = “Germany”, Age = “20–40” and Gender = “Woman”}. The experiments show that, when the number of required visits by advertisers is low, it is easy to find configurations with high average profitability, but as the required number of visits increases, the average profitability diminishes. Additionally, configuration optimisation has been combined with other interesting strategies to increase, even more, the campaigns’ profitability. In particular, the presented study considers the following complementary strategies to increase profitability: (1) selecting multiple configurations with a small number of visits rather than a unique configuration with a large number of visits, (2) discarding visits according to certain cost and profitability thresholds, (3) analysing a reduced space of the dataset and extrapolating the solution over the whole dataset, and (4) increasing the search space by including solutions below the required number of visits. The developed campaign optimisation methodology could be offered by RTB and other advertising platforms to advertisers to make their campaigns more profitable.