bluuebunny/crossref_metadata_2025 huggingface dataset:
Neutrino mass, mixing and muon g − 2 explanation in $$ \mathrm{U}{(1)}_{L_{\mu }-{L}_{\tau }} $$ extension of left-right theory
Authors: Majumdar Chayan , Patra Sudhanwa , Pritimita Prativa , Senapati Supriya , Yajnik Urjit A.
Published: September 2020

Abstract

We consider a gauged $$ \mathrm{U}{(1)}_{L_{\mu }-{L}_{\tau }} $$
U

1

L
μ

−

L
τ

extension of the left-right symmetric theory in order to simultaneously explain neutrino mass, mixing and the muon anomalous magnetic moment. We get sizeable contribution from the interaction of the new light gauge boson Zμτ of the $$ \mathrm{U}{(1)}_{L_{\mu }-{L}_{\tau }} $$
U

1

L
μ

−

L
τ

symmetry with muons which can individually satisfy the current bounds on muon (g − 2) anomaly (∆aμ). The other positive contributions to ∆aμ come from the interactions of singly charged gauge bosons WL, WR with heavy neutral fermions and that of neutral CP-even scalars with muons. The interaction of WL with heavy neutrino is facilitated by inverse seesaw mechanism which allows large light-heavy neutrino mixing and explains neutrino mass in our model. CP-even scalars with mass around few hundreds GeV can also satisfy the entire current muon anomaly bound. The results show that the model gives a small but non-negligible contribution to ∆aμ thereby eliminating the entire deviation in theoretical prediction and experimental result of muon (g − 2) anomaly. We have briefly presented a comparative study for symmetric and asymmetric left-right symmetric model in context of various contribution to ∆aμ. We also discuss how the generation of neutrino mass is affected when left-right symmetry breaks down to Standard Model symmetry via various choices of scalars.
Logarithmic negativity in quantum Lifshitz theories
Authors: Angel-Ramelli J. , Berthiere C. , Puletti V. Giangreco M. , Thorlacius L.
Published: September 2020

Abstract

We investigate quantum entanglement in a non-relativistic critical system by calculating the logarithmic negativity of a class of mixed states in the quantum Lifshitz model in one and two spatial dimensions. In 1+1 dimensions we employ a correlator approach to obtain analytic results for both open and periodic biharmonic chains. In 2+1 dimensions we use a replica method and consider spherical and toroidal spatial manifolds. In all cases, the universal finite part of the logarithmic negativity vanishes for mixed states defined on two disjoint components. For mixed states defined on adjacent components, we find a non-trivial logarithmic negativity reminiscent of two-dimensional conformal field theories. As a byproduct of our calculations, we obtain exact results for the odd entanglement entropy in 2+1 dimensions.
Black rubber and the non-linear elastic response of scale invariant solids
Authors: Baggioli Matteo , Castillo Víctor Cáncer , Pujolàs Oriol
Published: September 2020

Abstract

We discuss the nonlinear elastic response in scale invariant solids. Following previous work, we split the analysis into two basic options: according to whether scale invariance (SI) is a manifest or a spontaneously broken symmetry. In the latter case, one can employ effective field theory methods, whereas in the former we use holographic methods. We focus on a simple class of holographic models that exhibit elastic behaviour, and obtain their nonlinear stress-strain curves as well as an estimate of the elasticity bounds — the maximum possible deformation in the elastic (reversible) regime. The bounds differ substantially in the manifest or spontaneously broken SI cases, even when the same stress- strain curve is assumed in both cases. Additionally, the hyper-elastic subset of models (that allow for large deformations) is found to have stress-strain curves akin to natural rubber. The holographic instances in this category, which we dub black rubber, display richer stress- strain curves — with two different power-law regimes at different magnitudes of the strain.
Building a consistent parton shower
Authors: Forshaw Jeffrey R. , Holguin Jack , Plätzer Simon
Published: September 2020

Abstract

Modern parton showers are built using one of two models: dipole showers or angular ordered showers. Both have distinct strengths and weaknesses. Dipole showers correctly account for wide-angle, soft gluon emissions and track the leading flows in QCD colour charge but they are known to mishandle partonic recoil. Angular ordered showers keep better track of partonic recoil and correctly include large amounts of wide-angle, soft physics but azimuthal averaging means they are known to mishandle some correlations. In this paper, we derive both approaches from the same starting point; linking our under- standing of the two showers. This insight allows us to construct a new dipole shower that has all the strengths of a standard dipole shower together with the collinear evolution of an angular-ordered shower. We show that this new approach corrects the next-to-leading- log errors previously observed in parton showers and improves their sub-leading-colour accuracy.
Complex Langevin analysis of 2D U(1) gauge theory on a torus with a θ term
Authors: Hirasawa Mitsuaki , Matsumoto Akira , Nishimura Jun , Yosprakob Atis
Published: September 2020

Abstract

Monte Carlo simulation of gauge theories with a θ term is known to be extremely difficult due to the sign problem. Recently there has been major progress in solving this problem based on the idea of complexifying dynamical variables. Here we consider the complex Langevin method (CLM), which is a promising approach for its low computational cost. The drawback of this method, however, is the existence of a condition that has to be met in order for the results to be correct. As a first step, we apply the method to 2D U(1) gauge theory on a torus with a θ term, which can be solved analytically. We find that a naive implementation of the method fails because of the topological nature of the θ term. In order to circumvent this problem, we simulate the same theory on a punctured torus, which is equivalent to the original model in the infinite volume limit for |θ| < π. Rather surprisingly, we find that the CLM works and reproduces the exact results for a punctured torus even at large θ, where the link variables near the puncture become very far from being unitary.
Predictive S4 flavon model with TM1 mixing and baryogenesis through leptogenesis
Authors: Chakraborty Mainak , Krishnan R. , Ghosal Ambar
Published: September 2020

Abstract

We use S4 discrete group to construct a neutrino flavour model which leads to T M1 mixing and is consistent with the neutrino oscillation data. Using the model’s constrained parameter space, we predict the values of Dirac C P phase and the light neutrino mass as −1 < sin δ < −0.9 and 1.7 < m1(meV) < 5.5 respectively. We thoroughly examine the usefulness of this model in explaining the observed baryon asymmetry of the Universe. Near-maximal breaking of CP symmetry (arising due to the TM1 constraint) helps us in generating adequate baryon asymmetry through leptogenesis. We study the evolution of the asymmetry (generated due to the decay of the heavy Majorana neutrinos) starting from the primordial Universe in two different ways (i)explicitly solving network of Boltzmann equations, (ii) using approximate analytic solution and we have shown the extent of their equivalence. Nearly accurate analytical fits are used thereafter to evaluate baryon asymmetry for the whole parameter space allowed by 3σ global fit of oscillation data and to impose a constraint on the yet unbounded mass scale parameter of Dirac neutrino mass matrix. Furthermore, significant contribution of N2 decay in the context of flavoured leptogenesis is also estimated.
Quantum quench and thermalization to GGE in arbitrary dimensions and the odd-even effect
Authors: Banerjee Parijat , Gaikwad Adwait , Kaushal Anurag , Mandal Gautam
Published: September 2020

Abstract

In many quantum quench experiments involving cold atom systems the post-quench phase can be described by a quantum field theory of free scalars or fermions, typically in a box or in an external potential. We will study mass quench of free scalars in arbitrary spatial dimensions d with particular emphasis on the rate of relaxation to equilibrium. Local correlators expectedly equilibrate to GGE; for quench to zero mass, interestingly the rate of approach to equilibrium is exponential or power law depending on whether d is odd or even respectively. For quench to non-zero mass, the correlators relax to equilibrium by a cosine-modulated power law, for all spatial dimensions d, even or odd. We briefly discuss generalization to O(N ) models.
Macrophage migration inhibitory factor is regulated by HIF-1α and cAMP and promotes renal cyst cell proliferation in a macrophage-independent manner
Authors: Safi Wajima , Kraus Andre , Grampp Steffen , Schödel Johannes , Buchholz Bjoern
Published: September 2020

Progressive cyst growth leads to decline of renal function in polycystic kidney disease. Macrophage migration inhibitory factor (MIF) was found to be upregulated in cyst-lining cells in a mouse model of polycystic kidney disease and to promote cyst growth. In addition, MIF can be secreted by tubular cells and may contribute to cyst growth in an autocrine manner. However, the underlying mechanisms leading to induction of MIF in cyst-lining cells remained elusive. Here, we demonstrate that hypoxia-inducible transcription factor (HIF) 1α upregulates MIF in cyst-lining cells in a tubule-specific PKD1 knockout mouse. Pharmacological stabilization of HIF-1α resulted in significant increase of MIF in cyst epithelial cells whereas tubule-specific knockout of HIF-1α prevented MIF upregulation. Identical regulation could be found for ABCA1, which has been shown to act as a transport protein for MIF. Furthermore, we show that MIF and ABCA1 are direct target genes of HIF-1α in human primary tubular cells. Next to HIF-1α and hypoxia, we found MIF being additionally regulated by cAMP which is a strong promotor of cyst growth. In line with these findings, HIF-1α- and cAMP-dependent in vitro cyst growth could be decreased by the MIF-inhibitor ISO-1 which resulted in reduced cyst cell proliferation. In conclusion, HIF-1α and cAMP regulate MIF in primary tubular cells and cyst-lining epithelial cells, and MIF promotes cyst growth in the absence of macrophages. In line with these findings, the MIF inhibitor ISO-1 attenuates HIF-1α- and cAMP-dependent in vitro cyst enlargement.

Key messages

• MIF is upregulated in cyst-lining cells in a polycystic kidney disease mouse model.

• MIF upregulation is mediated by hypoxia-inducible transcription factor (HIF) 1α.

• ABCA1, transport protein for MIF, is also regulated by HIF-1α in vitro and in vivo.

• MIF is additionally regulated by cAMP, a strong promotor of cyst growth.

• MIF-inhibitor ISO-1 reduces HIF-1α- and cAMP-dependent cyst growth.
Label-free CARS microscopy reveals similar triacylglycerol acyl chain length and saturation in myocellular lipid droplets of athletes and individuals with type 2 diabetes
Authors: Daemen Sabine , Gemmink Anne , Paul Alexandra , Billecke Nils , Rieger Katrina , Parekh Sapun H. , Hesselink Matthijs K. C.
Published: September 2020

Aims/hypothesis

Intramyocellular lipid (IMCL) content associates with development of insulin resistance, albeit not in insulin-sensitive endurance-trained athletes (trained). Qualitative and spatial differences in muscle lipid composition may underlie this so-called athlete’s paradox. Here we studied triacylglycerol (TAG) composition of individual myocellular lipid droplets (LDs) in trained individuals and individuals with type 2 diabetes mellitus.

Methods

Trained ($$ \dot{V}{\mathrm{O}}_{2\max } $$

V
̇

O

2
max

71.0 ± 1.6 ml O2 [kg lean body mass (LBM)]−1 min−1), normoglycaemic (fasting glucose 5.1 ± 0.1 mmol/l) individuals and untrained ($$ \dot{V}{\mathrm{O}}_{2\max } $$

V
̇

O

2
max

36.8 ± 1.5 ml O2 [kg LBM]−1 min−1) individuals with type 2 diabetes (fasting glucose 7.4 ± 0.5 mmol/l), with similar IMCL content (3.5 ± 0.7% vs 2.5 ± 0.3%, p = 0.241), but at opposite ends of the insulin sensitivity spectrum (glucose infusion rate 93.8 ± 6.6 vs 25.7 ± 5.3 μmol [kg LBM]−1 min−1 for trained individuals and those with type 2 diabetes, respectively) were included from our database in the present study. We applied in situ label-free broadband coherent anti-Stokes Raman scattering (CARS) microscopy to sections from skeletal muscle biopsies to measure TAG acyl chain length and saturation of myocellular LDs. This approach uniquely permits examination of individual LDs in their native environment, in a fibre-type-specific manner, taking into account LD size and subcellular location.

Results

Despite a significant difference in insulin sensitivity, we observed remarkably similar acyl chain length and saturation in trained and type 2 diabetic individuals (chain length: 18.12 ± 0.61 vs 18.36 ± 0.43 number of carbons; saturation: 0.37 ± 0.05 vs 0.38 ± 0.06 number of C=C bonds). Longer acyl chains or higher saturation (lower C=C number) could be detected in subpopulations of LDs, i.e. large LDs (chain length: 18.11 ± 0.48 vs 18.63 ± 0.57 carbon number) and subsarcolemmal LDs (saturation: 0.34 ± 0.02 vs 0.36 ± 0.04 C=C number), which are more abundant in individuals with type 2 diabetes.

Conclusions/interpretation

In contrast to reports of profound differences in the lipid composition of lipids extracted from skeletal muscle from trained and type 2 diabetic individuals, our in situ, LD-specific approach detected only modest differences in TAG composition in LD subpopulations, which were dependent on LD size and subcellular location. If, and to what extent, these modest differences can impact insulin sensitivity remains to be elucidated.
In vitro biotransformation of pyrrolizidine alkaloids in different species: part II—identification and quantitative assessment of the metabolite profile of six structurally different pyrrolizidine alkaloids
Authors: Geburek Ina , Schrenk Dieter , These Anja
Published: September 2020

Pyrrolizidine alkaloids (PA) exert their toxic effects only after bioactivation. Although their toxicity has already been studied and metabolic pathways including important metabolites were described, the quantification of the latter revealed a large unknown portion of the metabolized PA. In this study, the qualitative and quantitative metabolite profiles of structurally different PAs in rat and human liver microsomes were investigated. Between five metabolites for europine and up to 48 metabolites for lasiocarpine were detected. Proposals for the chemical structure of each metabolite were derived based on fragmentation patterns using high-resolution mass spectrometry. The metabolite profiles of the diester PAs showed a relatively good agreement between both species. The metabolic reactions were summarized into three groups: dehydrogenation, oxygenation, and shortening of necic acid(s). While dehydrogenation of the necine base is considered as bioactivation, both other routes are considered as detoxification steps. The most abundant changes found for open chained diesters were dealkylations, while the major metabolic pathway for cyclic diesters was oxygenation especially at the nitrogen atom. In addition, all diester PAs formed several dehydrogenation products, via the insertion of a second double bond in the necine base, including the formation of glutathione conjugates. In rat liver microsomes, all investigated PAs formed dehydropyrrolizidine metabolites with the highest amount formed by lasiocarpine, whereas in human liver microsomes, these metabolites could only be detected for diesters. Our findings demonstrate that an extensive analysis of PA metabolism can provide the basis for a better understanding of PA toxicity and support future risk assessment.
In vitro antifungal activity of Cinnamomum zeylanicum bark and leaf essential oils against Candida albicans and Candida auris
Authors: Tran Hoang N. H. , Graham Lee , Adukwu Emmanuel C.
Published: September 2020

Candida infections are a significant source of patient morbidity and mortality. Candida albicans is the most common pathogen causing Candida infections. Candida auris is a newly described pathogen that is associated with multi-drug-resistant candidiasis and candidaemia in humans. The antifungal effects of various essential oils and plant compounds have been demonstrated against human pathogenic fungi. In this study, the effect of cinnamon leaf and bark essential oils (CEOs) was determined against both C. albicans and C. auris. The disc diffusion (direct and vapour) and broth microdilution method was used to determine antifungal activity of the EOs against selected strains (C. albicans ATCC 10231, C. albicans ATCC 2091 and C. auris NCPF 8971) whilst the mode of action and haemolysin activity of the CEOs were determined using electron microscopy and light microscopy. Direct and vapour diffusion assays showed greater inhibitory activity of bark CEO in comparison with leaf CEO. The minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of bark CEO for all tested strains was below 0.03% (v/v), which was lower than the MICs of the leaf CEO (0.06–0.13%, v/v) dependent on the strain and the MFCs at 0.25% (v/v). In the morphological interference assays, damage to the cell membrane was observed and both CEOs inhibited hyphae formation. The haemolysin production assay showed that CEOs can reduce the haemolytic activity in the tested C. albicans and C. auris strains. At low concentrations, CEOs have potent antifungal and antihaemolytic activities in vitro against C. albicans and C. auris.

Key points

• Essential oils from Cinnamomum zeylanicum Blume bark and leaf (CBEO and CLEO) demonstrated fungicidal properties at very low concentrations.

• The antifungal activity of CBEO was greater than that of CLEO consistent with other recent published literature.

• The mode of action of CBEO and CLEO was damage to the membrane of C. albicans and C. auris.

• Both CBEO and CLEO inhibited the formation of hyphae and reduced haemolysin production in C. albicans and C. auris.
Sex differences in ocular morphology in Caucasian people: a dubious role of sexual selection in the evolution of sexual dimorphism of the human eye
Authors: Danel Dariusz P. , Wacewicz Sławomir , Kleisner Karel , Lewandowski Zdzisław , Kret Mariska E. , Żywiczyński Przemysław , Perea-Garcia Juan Olvido
Published: September 2020

The horizontal size of the exposed depigmented sclera in Caucasians has been previously suggested to be sexually dimorphic, and the significance of this phenomenon remains unclear. Here we build on a previous study and extend it by (i) examining sex differences in other measures of ocular morphology and (ii) exploring the link between eye morphology and biometric markers of facial attractiveness. We used facial photographs of 100 Caucasians (50 men) from Eastern-Central Europe and digitally measured four ocular features. Eye measurements were tested for sex differences and associations with morphometric data on facial averageness and sexual shape dimorphism. We found that sclera surface is more horizontally exposed in men, even though the total surface area is similar in both sexes. We also found that eye fissures are rounder (less rectangular) in women than in men and that irises are brighter in women. We did not find any relationship between the examined eye features and two aspects of facial attractiveness: facial averageness and sexual dimorphism in facial shape. Despite being sexually dimorphic, eye features may be loosely linked with the development of facial sexual ornamentation. The role of sexual selection in the evolution of the observed phenomena is disputable.

Significance statement

It is often argued that because of their physical appearance, human eyes are crucial to interpersonal and social interactions. In many aspects, however, the significance of the human eye architecture is unclear. In this study, we examine sex differences in eye morphology and explore the link between ocular features and biometric measures of facial attractiveness in Caucasian men and women. We found that despite being sexually dimorphic, eye features may be loosely linked with biometric markers of facial attractiveness. We argue that the role of sexual selection in the evolution of the observed sex differences is disputable.
A review of the challenges in mobile manipulation: systems design and RoboCup challenges
Authors: Sereinig Martin , Werth Wolfgang , Faller Lisa-Marie
Published: September 2020

Mobile robotics is already well established in today’s production lines. Navigation, control and perception for mobile robots are vivid fields of research fostering advances in Industry 4.0. In order to increase the flexibility of such mobile platforms, it is also common practice to add serial manipulator arms to their yielding systems with nine degrees of freedom and more. These platforms are not limited to industry but are supportive in various field such as service, assistance, teleoperation and also rehabilitation. Due to the operation of such increasingly complex systems in less structured and dynamic environments - often in close contact with humans - more demanding challenges evolve in terms of systems design, control and sensors. These challenges are also reflected in the various RoboCup leagues. In this paper, we discuss state-of-the-art developments in mobile manipulation using developments and work done in the context of the RoboCup competition as design examples. Additionally, we elaborate on the recent challenges of the RoboCup Rescue League as well as on the RoboCup@Work League.
Patient satisfaction after breast cancer surgery
Authors: Leser Carmen , Tan Yen Y. , Singer Christian , Zeillinger Robert , Fitzal Florian , Lehrner Johann , König Daniel , Deutschmann Christine , Gschwantler-Kaulich Daphne
Published: September 2020

Background

This study investigated the impact of curative breast cancer surgery on patient satisfaction concerning cosmetic results and quality of life (QoL).

Methods

In this study 61 participants completed questionnaires to evaluate their QoL and patient satisfaction with cosmetic results following breast cancer surgery. Cosmetic outcomes were evaluated by the breast surgeon and an independent breast specialist using the Harris scale and the breast analyzing tool (BAT).

Results

Of the participants 71% completed all 4 follow-up visits, 38 (62%) patients received breast-conserving therapy (BCT) and 23 (38%) received a mastectomy. Surgery-associated complications arose in 2.6% of the patients who received BCT and 17.4% of patients who received a mastectomy. No significant differences in QoL between BCT patients and mastectomy patients were observed immediately after surgery, or after 6 and 12 months. Breast asymmetry, measured using the BAT score, and QoL scores were worst immediately after surgery. The surgeon rated the cosmetic results as better compared to the independent breast expert (p = 0.001). Furthermore, patients aged over 60 years old were less satisfied with the cosmetic outcome compared to younger patients at the time of discharge (p = 0.024). Patients who received a mastectomy were less satisfied when the resected volume was higher.

Conclusion

Patient satisfaction was lowest immediately after surgery but improved during the following months, despite continued breast asymmetry. For mastectomy patients, a lower resected volume led to a higher satisfaction with cosmetic results. Satisfaction is subjective and cannot be determined from the esthetic satisfaction of the surgeon or using an objective tool measuring breast asymmetry.
Multidimensional assessment of cervical spondylotic myelopathy patients. Usefulness of a comprehensive score system
Authors: Pilato Fabio , Calandrelli Rosalinda , Distefano Marisa , Tamburrelli Francesco Ciro
Published: September 2020

Objective

Cervical spondylotic myelopathy (CSM) is caused by cervical spine degeneration and surgery may be beneficial, but selection for surgery might be challenging. We performed a multimodal analysis to assess predicting factors that may be useful to help surgeons in this choice.

Patients and methods

We retrospectively evaluated clinical, motor evoked potentials (MEP), and MRI data of patients who undergone surgery for CSM. Seventy-six consecutive patients (46 males) were enrolled. The median age was 65.5 [IQR: 57–71] years, and the duration of symptoms was 11 [8–13] months. A multivariate analysis in order to assess predictors of outcome and ROC curve analysis were performed.

Results

Thirty patients (M:18, 39.5%) gained 6 or more points on mJOA and they were collected in good recovery group, whereas 46 patients (60.5%, M:28) showed a fair recovery. We developed a comprehensive score system (CSS) taking into account clinical, neurophysiological, and neuroradiological data. ROC curve analysis was performed to determine the discriminative power of four models derived from the multivariate logistic regression analysis for predictors of good outcome considering only clinical variables, MRI variables, and MEP variables or considering the comprehensive model, demonstrating a good accuracy of CSS model to predict outcome.

Conclusion

This study demonstrates that CSS model taking into consideration functional assessment by mJOA score, neurologic evaluation, cervical MRI, and MEP may be a feasible method to predict outcome in patients candidate to surgery, supporting surgeon’s decisions both for those patients candidate to surgery and for patients in whom a “wait and see” approach could be proposed.
Heterogeneous approach to nebulization of antimicrobial agents in mechanically ventilated adults in a German tertiary care hospital: a cross-sectional survey
Authors: Pfäfflin Frieder , Stegemann Miriam , Suttorp Norbert , Uhrig Alexander , Achterberg Stephan
Published: September 2020

There is lack of standardization of practices and limited evidence on efficacy and safety of nebulization of antimicrobials. We sought to determine inhalation practices in one tertiary care hospital by performing a cross-sectional survey. Eleven adult ICUs were included in the analysis. Three units followed established protocols. Ventilation circuit filters were exchanged at least daily in all but one units. Dosages of aminoglycosides and CMS depended on indication and unit. Nebulization of antimicrobials was generally regarded as safe and efficacious. Our data indicate that approach to nebulization of antimicrobials may be heterogeneous even in a single center.
Efficient synthesis of γ-glutamyl compounds by co-expression of γ-glutamylmethylamide synthetase and polyphosphate kinase in engineered Escherichia coli
Authors: Pan Xinru , Yu Jinhai , Du Qinglin , Zeng Shuiyun , Liu Junzhong , Jiao Qingcai , Zhang Hongjuan
Published: September 2020

γ-Glutamyl compounds have unveiled their importance as active substances or precursors of pharmaceuticals. In this research, an approach for enzymatic synthesis of γ-glutamyl compounds was developed using γ-glutamylmethylamide synthetase (GMAS) from Methylovorus mays and polyphosphate kinase (PPK) from Corynebacterium glutamicum. GMAS and PPK were co-recombined in pETDuet-1 plasmid and co-expressed in E. coli BL21 (DE3), and the enzymatic properties of GMAS and PPK were investigated, respectively. Under the catalysis of the co-expression system, l-theanine was synthesized with 89.8% conversion when the substrate molar ratio of sodium glutamate and ethylamine (1:1.4) and only 2 mM ATP were used. A total of 14 γ-glutamyl compounds were synthesized by this one-pot method and purified by cation exchange resin and isoelectric point crystallization with a yield range from 22.3 to 72.7%. This study provided an efficient approach for the synthesis of γ-glutamyl compounds by GMAS and PPK co-expression system.
Synthetic biology, combinatorial biosynthesis, and chemo‑enzymatic synthesis of isoprenoids
Authors: Malico Alexandra A , Calzini Miles A , Gayen Anuran K , Williams Gavin J
Published: September 2020

Isoprenoids are a large class of natural products with myriad applications as bioactive and commercial compounds. Their diverse structures are derived from the biosynthetic assembly and tailoring of their scaffolds, ultimately constructed from two C5 hemiterpene building blocks. The modular logic of these platforms can be harnessed to improve titers of valuable isoprenoids in diverse hosts and to produce new-to-nature compounds. Often, this process is facilitated by the substrate or product promiscuity of the component enzymes, which can be leveraged to produce novel isoprenoids. To complement rational enhancements and even re-programming of isoprenoid biosynthesis, high-throughput approaches that rely on searching through large enzymatic libraries are being developed. This review summarizes recent advances and strategies related to isoprenoid synthetic biology, combinatorial biosynthesis, and chemo-enzymatic synthesis, focusing on the past 5 years. Emerging applications of cell-free biosynthesis and high-throughput tools are included that culminate in a discussion of the future outlook and perspective of isoprenoid biosynthetic engineering.
An attempt to identify technologically relevant papers based on their references
Authors: Yamashita Yasuhiro
Published: September 2020

In this study, two indicators derived from references in papers were proposed to characterize the papers regarding technological relevance: (1) the number of reference papers that obtained citations from patents by the time of observation, i.e., the publication years of papers to be assessed (NR-PCP), and (2) the number of reference papers authored by the firms’ researchers (NR-FP). Next, the two indicators were applied to papers published in 2001 to assess their performance. The results obtained by the two indicators were evaluated by citations from patents until 2016 in various conditions: scientific field, institutional sector, and period of measurement. Results showed a robustness of both indicators in many conditions. NR-PCP showed better results in most cases than NR-FP, although its recall was inferior to NR-FP for papers in which all references were newer than 1996. Based on the result that NR-PCP was preferred as an indicator, the rationale of using reference papers cited in the patent by the period of observation (R-PCP) as an indicator was considered based on the papers’ potential distances from the border between science and technology, which was obtained from an extended version of the citation network originally proposed by Ahmadpoor and Jones (Science 357:583–587, 2017.10.1126/science.aam9527). Finally, issues to be addressed were discussed.
Sphaeropsis sapinea and fungal endophyte diversity in twigs of Scots pine (Pinus sylvestris) in Germany
Authors: Bußkamp Johanna , Langer Gitta Jutta , Langer Ewald Johannes
Published: September 2020

Sphaeropsis sapineais the causal fungal agent of Diplodia tip blight disease of Scots pine (Pinus sylvestris) and other coniferous trees of relevance to forestry in Germany. In this study, the distribution and occurrence ofS. sapineaand accompanying endophytic fungi in twigs of healthy and diseased Scots pine was investigated on a spatial and temporal scale. Sampling of 26,000 twig segments from trees in 105 temperate coniferous forest stands in Germany resulted in isolation of 33,000 endophytic fungi consisting of 103 species identified based on morphological and ITS-DNA sequence analyses. Approximately 98% of the sample was represented by fungi in the Ascomycota, with only two species (Peniophora piniandCoprinellussp.) belonging to the Basidiomycota. Four species were detected in a frequency greater than 10% (Sphaeropsis sapinea,Sydowia polyspora,Microsphaeropsis olivacea,andTruncatella conorum-piceae) from the collective sample. A typical inhabitant of Scots pine twigsDesmazierella acicolawas isolated and additionally typical hardwood colonizers likeBiscogniauxiaspp. were detected.S. sapinea, an endophytic plant pathogen with saprobic capabilities, was isolated from more than 80% of the studied pine trees, but the majority of trees sampled showed no symptoms of Diplodia tip blight. No invasive, pathogenic quarantine fungi for Germany were isolated from healthy or diseased Scots pines. Advantages and disadvantages of isolation-based endophyte studies over studies using direct DNA-isolation are discussed. Knowledge of the fungal endophyte communities in twigs of Scots pine allowed for identificationS. sapineaand other potential pathogens of pines and other forest trees that may possibly contribute to increased disease under repeated periods of drought and heat stress in the future.
Spermatozoa induce transcriptomic alterations in bovine oviductal epithelial cells prior to initial contact
Authors: Reshi Qurat Ul Ain , Viil Janeli , Ord James , Lättekivi Freddy , Godakumara Kasun , Hasan Mohammad Mehedi , Nõmm Monika , Jääger Kersti , Velthut-Meikas Agne , Jaakma Ülle , Salumets Andres , Fazeli Alireza
Published: September 2020

The capability of spermatozoa to directly influence maternal gene expression is already established. Indeed, some of the changes induced by spermatozoa may have a direct functional importance in the pre-conceptional period. Although the mechanisms underlying these sperm-maternal interactions are not well characterized, it is possible that they could involve ligands that are released from the spermatozoa. This study therefore aimed to test whether physical contact between bovine spermatozoa and bovine oviductal epithelial cells (BOECs) is a prerequisite for spermatozoa-induced gene expression changes. We used two co-culture models: a contact co-culture model in which spermatozoa interact directly with BOECs, and a non-contact co-culture model in which an insert with the pore size of 0.4 μm was placed between spermatozoa and BOECs. Messenger RNA sequencing analysis of BOECs by RNA-seq revealed ten differentially expressed genes in contact system and 108 differentially expressed genes in the non-contact system after 10 h of co-culture. Retinol metabolism pathway and ovarian steroidogenesis pathway were significantly enriched in the non-contact co-culture system. Q-PCR analysis revealed that transcriptional responses can be rapid, with increased expression of four genes (DHRS3,CYP1B1,PTGS2, andATF3) detectable within just 90 min of co-incubation, but with expression levels highly dependent on the type of co-culture system. The findings from our study demonstrate that direct contact with spermatozoa is not necessary to induce changes in gene expression of oviductal epithelial cells, suggesting that spermatozoa may be able to signal to maternal tissues in advance of their arrival.
Brief Compassion-Focused Imagery Dampens Physiological Pain Responses
Authors: Maratos Frances A. , Sheffield David
Published: September 2020

Objectives

Affiliative processes are postulated to improve pain coping. Comparatively, compassion-focused imagery (CFI) also stimulates affiliate affect systems with a burgeoning behavioural, cognitive and physiological evidence base. Thus, the purpose of the present research was to investigate if engaging in brief CFI could improve pain coping.

Methods

Utilising a randomised repeated measures crossover design, 37 participants were subjected to experimental pain (cold pressor) following counter-balanced engagement with CFI or control imagery, 1 week apart. Salivary alpha-amylase (sAA) and questionnaire measures of emotional responding were taken: at baseline, following introduction to the imagery condition (anticipation), and immediately after the cold pressor pain task (actual).

Results

Participants exhibited increases in sAA levels in response to pain following control imagery but, no such changes were observed following CFI (i.e. there was a significant time-by-condition interaction). Pain tolerance (the length of time participants immersed their hands in the cold pressor) did not differ by imagery condition. However, sAA responses to actual pain predicted decreased pain tolerance in the CFI condition. Additionally, anticipatory sAA response predicted increased pain tolerance across both conditions. None of the emotional measures of well-being differed by imagery condition, nor by condition over time.

Conclusions

These data demonstrate that using CFI can curtail a physiological stress response to pain, as indicated by increases in sAA in the control imagery condition only, following pain; pain tolerance was not influenced by CFI. Compassion-based approaches may therefore help people cope with the stress associated with pain.
Cultural innovative enterprises: not just philantrophy
Authors: Guizzardi Silvia
Published: September 2020

This paper is focused on the “cultural innovative enterprises”, introduced into italian law by Decree Law 179/2012 on “Further urgent measures for Italy’s economic growth”, converted into Law 221/2012. It is about new innovative enterprises that deal to develop, manufacture and distribuite innovative goods and services of high technological value, operating exclusively in the fields of cultural heritage promotion and cultural services provision. These companies can contribute to reduce the Italian youth employment emergency thanks on one hand to the reduced entry barriers related to the technology developments needed to “begin doing business” and on the other hand to the widespread territorial distribution of the italian cultural heritage to which services and processes will be applied. Furthermore, the increase of the GDP in regions undergoing a state of economic difficulty is a goal at hand. From a more general point of view, the cultural innovative start ups are an important element in stimulating new forms of collaboration between public entities responsible for the protection of the artistic heritage and private companies involved in its promotion. This type of partnership can contribute to the promotion and dissemination of new essential skills within the public administration aimed at a virtuous evolution of the way the overall economic system works.
Operation and operation approval of high-altitude platforms
Authors: Nikodem F. , Kaltenhäuser S.
Published: September 2020

Recently, the European Aviation Safety Agency and other civil aviation authorities introduced a regulatory framework for low- and medium-risk operations of unmanned aerial systems (UAS) where medium-risk operations fall into the ‘specific’ category. Other introduced categories are the ‘open’ category for very-low-risk operations and the ‘certified’ category for high-risk operations that are comparable to manned aviation. This framework has the potential to reduce the certification costs compared to manned civil aviation. This paper discusses the challenges for operators of high-altitude platforms who aim for medium-risk UAS operations in the ‘specific’ category. It also shows ways to obtain an operation approval in the ‘specific’ category and how to deal with the associated operational requirements to perform such long-endurance UAS missions. Moreover, problems the high-altitude platform operator has to face when applying SORA are discussed. The paper closes with a promising approach to further enable high-altitude operations and to face some of the problems that occurred in the applicability of SORA to high-altitude platform operations by the use of 4D-operational volumes and unmanned traffic management (UTM) services.
Neolignans and Norlignans from Insect Medicine Polyphaga plancyi and Their Biological Activities
Authors: Zhu Hong-Jie , Xu Te , Yan Yong-Ming , Tu Zheng-Chao , Cheng Yong-Xian
Published: September 2020

Ten neolignans or norlignans (1–10) including eight new compounds were isolated from the whole bodies of Polyphaga plancyi Bolivar. Their structures were identified by spectroscopic data. Compounds 3, 4, 8, and 9 are racemates indicated by chiral HPLC analysis. Chiral separation followed by ECD calculations allowed to clarify the absolute configurations of all the antipodes. All the new compounds were evaluated for their biological properties toward extracellular matrix in rat renal proximal tubular cells, human cancer cells (K562, A549, and Huh7), EV71, ROCK2, JAK3, DDR1, and coagulation.

Graphic Abstract
Variability in Regional Ecological Vulnerability: A Case Study of Sichuan Province, China
Authors: Liu Yimeng , Yang Saini , Han Chuanliang , Ni Wei , Zhu Yuyao
Published: September 2020

Rapid urbanization and natural hazards are posing threats to local ecological processes and ecosystem services worldwide. Using land use, socioeconomic, and natural hazards data, we conducted an assessment of the ecological vulnerability of prefectures in Sichuan Province for the years 2005, 2010, and 2015 to capture variations in its capacity to modulate in response to disturbances and to explore potential factors driving these variations. We selected five landscape metrics and two topological indicators for the proposed ecological vulnerability index (EVI), and constructed the EVI using a principal component analysis-based entropy method. A series of correlation analyses were subsequently performed to identify the factors driving variations in ecological vulnerability. The results show that: (1) for each of the study years, prefectures with high ecological vulnerability were located mainly in southern and eastern Sichuan, whereas prefectures in central and western Sichuan were of relatively low ecological vulnerability; (2) Sichuan’s ecological vulnerability increased significantly (p = 0.011) during 2005–2010; (3) anthropogenic activities were the main factors driving variations in ecological vulnerability. These findings provide a scientific basis for implementing ecological protection and restoration in Sichuan as well as guidelines for achieving integrated disaster risk reduction.
Unilateral and Bilateral Laryngeal Pacing for Bilateral Vocal Fold Paralysis
Authors: Powell Maria E. , Zealear David L. , Li Yike , Garrett C. Gaelyn , Von Wahlde Kate , Netterville James
Published: September 2020

Purpose of Review

Present the state-of-the-art overview of laryngeal pacing for treatment of bilateral vocal fold paralysis. A minimally invasive unilateral pacing system and a fully implantable bilateral pacing system are currently in clinical trials. The relative advantages and disadvantages of each are discussed.

Recent Findings

Research in functional electrical stimulation for the reanimation of the posterior cricoarytenoid muscle has successfully translated from animal models to human clinical trials for unilateral pacing and bilateral pacing. Current findings suggest unilateral pacing in humans significantly improves ventilation but only marginally better than cordotomy. Bilateral pacing in canines increases glottal opening greater than 2-fold over unilateral pacing and restores exercise tolerance to normal.

Unilateral pacing can be considered a breathing assist device and may not be appropriate for active individuals. Bilateral pacing may be preferable for patients who wish to engage in strenuous exercise. Minimally invasive systems may be ideal for patients who prefer less invasive implantation and are not concerned with cosmesis. Fully implantable pacing systems offer greater electrode redundancy and stability, resulting in a system that is robust against electrode migration or damage.
Analysis of metal transfer and weld geometry in hot-wire GTAW with indirect resistive heating
Authors: Ungethüm T. , Spaniol E. , Hertel M. , Füssel U.
Published: September 2020

In this publication, the different metal transfer modes of a hot-wire GTAW process with indirect resistive preheating of the wire are presented. The hot-wire GTAW process is characterized by an additional preheating unit that is used to heat the wire before it reaches the melt pool. Thus, to preheat the wire, the contact between the melt pool and the wire is not necessary. In order to examine the metal transfer of the wire, deposition welds are analysed using a high-speed camera with a laser light source as well as a data acquisition unit. The presented results comprise the impact analysis of the GTAW current, the hot-wire current, the wire feeding rate, the wire feeding angle as well as the wire feeding direction. The observed metal transfer modes can be characterized as either a constant melting bridge (cmb) between the wire and the melt pool or a recurring melting bridge (rmb). The analysis also reveals that the influence of the process parameters and thus the metal transfer mode on the bead properties is only marginal.
Underground Metro Drivers: Occupational Problems and Job Satisfaction
Authors: Samerei Seyed Alireza , Aghabayk Kayvan , Akbarzade Mohamad Hosein
Published: September 2020

The performance of employees in a transport set is highly affected by their satisfaction and occupational problems. Underground metro drivers work in special conditions as compared with the drivers of suburban trains and urban tramways. Even though several studies have focused on the ergonomics of train drivers, there is a dearth of research on underground metro drivers. This study was conducted to investigate the factors affecting the underground metro drivers’ occupational problems such as depression and level of satisfaction. The study was carried out on underground metro drivers in Tehran, Iran. The required data were collected through interviews, self-report tests and a depression scale. The classification and regression tree (CART) model was used to measure the relationship among depression, different conditions and other demographic characteristics. By using hierarchical clustering, metro drivers were divided into two categories with desirable and undesirable levels of satisfaction with regard to varying levels of satisfaction in different fields. By labelling them and reusing the CART model, the most important parameters affecting the satisfaction of drivers were extracted. The results indicated that more than half of metro drivers were depressed. The most important factors in the incidence of depression were: resentment of some psychological factors such as dissatisfaction with loneliness in the cabin, stress and fear of an incident, fatigue, dissatisfaction with the resting place, work experience more than 3.5 years, dissatisfaction with rights and the need for a second job. Also, the most important factor affecting satisfaction was the quality of the resting place.
Decreased Stroke Presentation Rates at a Comprehensive Stroke Center during COVID-19
Authors: Dowlatshahi Dar , Stotts Grant , Bourgoin Aline , Gocan Sophia , Dunn Laura , Powell Jodi , Silver Frank L. , Walker Greg , Yogendrakumar Vignan , Fahed Robert , Blacquiere Dylan , Shamy Michel
Published: September 2020

We reviewed stroke care delivery during the COVID-19 pandemic at our stroke center and provincial telestroke system. We counted referrals to our prevention clinic, code strokes, thrombolysis, endovascular thrombectomies, and activations of a provincial telestroke system from February to April of 2017–2020. In April 2020, there was 28% reduction in prevention clinic referrals, 32% reduction in code strokes, and 26% reduction in telestroke activations compared to prior years. Thrombolysis and endovascular thrombectomy rates remained constant. Fewer patients received stroke services across the spectrum from prevention, acute care to telestroke care in Ontario, Canada, during the COVID-19 pandemic.