bluuebunny/crossref_metadata_2025 huggingface dataset:
An Optimal Measurement Strategy to Beat the Quantum Uncertainty in Correlated System
Authors: Li Jun‐Li , Qiao Cong‐Feng
Published: July 2020

Uncertainty principle is an inherent nature of quantum system that undermines the precise measurement of incompatible observables and hence the applications of quantum theory. Entanglement, another unique feature of quantum physics, may help to reduce the quantum uncertainty. In this paper, a practical method is proposed to reduce the one party measurement uncertainty by determining the measurement on the other party of an entangled bipartite system. In light of this method, a family of conditional majorization uncertainty relations in the presence of quantum memory is constructed, which is applicable to arbitrary number of observables. The new family of uncertainty relations implies sophisticated structures of quantum uncertainty and non‐locality, that are usually studied by using scalar measures. Applications to reduce the local uncertainty and to witness quantum non‐locality are also presented.
Preservation methods for the isotopic composition of dissolved carbon species in non‐ideal conditions
Authors: Wilson Jonathan , Munizzi Jordon , Erhardt Andrea M.
Published: July 2020

Rationale

The stable carbon isotope compositions of dissolved inorganic carbon (δ13CDIC) and dissolved organic carbon (δ13CDOC) are readily affected by post‐sampling microbial activity if not adequately preserved. Existing preservation methods require rapid chilling, analysis, and/or toxic chemicals, all challenging to use safely in the field and during remote field seasons. Therefore, a preservation method that is safe but also effective over a range of storage times is needed when sampling waters at very remote sites.

Methods

Two samples, with different dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC) concentrations, were filtered with a 0.2‐μm filter and preserved with six different methods, mercuric chloride, copper sulfate, phosphoric acid, benzalkonium chloride, zinc chloride, hydrochloric acid, and a filter‐only control. These samples were held at 4°C, 22°C, or 35°C. Regular measurement of the DIC and DOC δ13C values were made over the following 60 days for δ13CDIC and 66 days for δ13CDOC.

Results

Over the course of the experiment, mercuric chloride, copper sulfate, zinc chloride, and benzalkonium chloride resulted in δ13CDIC fractionation at both 4°C and 22°C. Only filtering to 0.2 μm at the time of collection, with or without acidification with phosphoric acid, resulted in minimal isotopic fractionation at both 4°C and 22°C and over the entirety of the experiment. For δ13CDOC values, only filtering to 0.2 μm minimized fractionation for both bulk and vial storage over 66 days at 22°C.

Conclusions

Filtering to 0.2 μm at the time of collection is more effective than the use of toxic chemicals for measuring δ13CDIC and δ13CDOC values. Phosphoric acid is as effective as only filtering for δ13CDIC and may be ideal depending on sampling considerations. These results demonstrate not only that water samples can be preserved for δ13CDIC and δ13CDOC analysis for long periods, but that preservation is best accomplished with non‐toxic or low‐toxicity methods.
An analysis of river fragmentation by dams and river dewatering in Costa Rica
Authors: Farah‐Pérez Aldo , Umaña‐Villalobos Gerardo , Picado‐Barboza Jorge , Anderson Elizabeth P.
Published: July 2020

Hydropower development is accelerating in the tropics, especially construction of small dams. Small dams are often classified as those lower than 15 m in height or with reservoir capacity less than 3 × 106 m3. Small dams frequently operate with water diversions from the main river channel, thereby affecting river connectivity through the creation of a dewatered reach. However, the extent and impact of dewatered reaches have been overlooked in most analyses of river fragmentation and dams to date. In Costa Rica, small dam development increased during the 1990s, ahead of current trends in other tropical regions. This study examined the effects of dams and their dewatered reaches on river connectivity at a national scale in Costa Rica. We adapted the Dendritic Connectivity Index and applied it to the four basins where over 80% of hydropower development has occurred. Our results showed that in two basins, the Sarapiqui and San Carlos, dewatered reaches contributed most to river fragmentation. In the Tarcoles and Reventazon basins, dams and dewatered reaches had similar effects on river fragmetnation. These different patterns can be explained by the spatial arrangement of dams in the individual river networks. We also found that dewatered reaches extended the elevation range of rivers affected by hydropower activity; this expansion was most significant in cases with interbasin water transfers. We discuss the implications of our findings on connectivity losses from dams for fishes whose range overlaps with hydropower activity. Our study may provide insights for other tropical countries with ongoing and future small dam development.
Supersymmetric Rényi entropy and charged hyperbolic black holes
Authors: Hosseini Seyed Morteza , Toldo Chiara , Yaakov Itamar
Published: July 2020

Abstract

The supersymmetric Rényi entropy across a spherical entangling surface in a d-dimensional SCFT with flavor defects is equivalent to a supersymmetric partition function on ℍd−1× 𝕊1, which can be computed exactly using localization. We consider the holographically dual BPS solutions in (d + 1)-dimensional matter coupled supergravity (d = 3, 5), which are charged hyperbolically sliced AdS black holes. We compute the renormalized on-shell action and the holographic supersymmetric Rényi entropy and show a perfect match with the field theory side. Our setup allows a direct map between the chemical potentials for the global symmetries of the field theories and those of the gravity solutions. We also discuss a simple case where angular momentum is added.
Leptogenesis in the μτ basis
Authors: Nishi Celso C. , Fong Chee Sheng
Published: July 2020

Abstract

We formulate three-flavor type-I leptogenesis in the μτ basis which is convenient because in the three-flavor regime, both μ and τ charged lepton Yukawa interactions are in thermal equilibrium and the thermal bath is symmetric under the exchange μ ↔ τ . We apply this formalism to models with μτ -reflection CPμτ symmetry. We confirm the previous result that leptogenesis fails in the three-flavor regime with exact CPμτ symmetry. Allowing CPμτ symmetry to be broken to various degrees, we show that leptogenesis can be successful in the three-flavor regime only in certain tuned parameter space, which could further imply additional symmetry is at play. As a bonus, we derive analytical expressions which could be utilized whenever the branching ratios for the decays to μ and τ flavors are equal or approximately so.
Photoproduction of three jets in the CGC: gluon TMDs and dilute limit
Authors: Altinoluk Tolga , Boussarie Renaud , Marquet Cyrille , Taels Pieter
Published: July 2020

Abstract

We study the process γA →$$ q\overline{q}g $$
q

q
¯

g
+ X in the Color Glass Condensate (CGC) effective theory. After obtaining the cross section, we consider two kinematic limits which are encompassed in our result. In the so-called correlation limit, the vector sum of the transverse momenta of the three outgoing particles is small with respect to the individual transverse momenta; the cross section then simplifies considerably and can be written in a factorized form, sensitive to both the unpolarized and linearly-polarized Weizsäcker-Williams transverse momentum dependent gluon distribution function (gluon TMD). The second limit of the CGC cross section that we consider is the dilute limit, which we obtain after performing a weak-field expansion; we recover a typical linear-regime expression, involving a single unintegrated gluon distribution function. Using numerical simulations of the small-x QCD evolution of the TMDs, we investigate the rapidity dependence of the cross section in the correlation limit.
LHC constraints on scalar diquarks
Authors: Pascual-Dias Bruna , Saha Pratishruti , London David
Published: July 2020

Abstract

A number of years ago, low-energy constraints on scalar diquarks, particles that couple to two quarks, were examined. It was found that the two most weakly-constrained diquarks are Du and Dd, colour antitriplets that couple to $$ {u}_R^i{u}_R^j $$

u
R
i

u
R
j

and $$ {d}_R^i{d}_R^j $$

d
R
i

d
R
j

, respectively. These diquarks have not been observed at the LHC. In this paper, we add the LHC measurements to the low-energy analysis, and find that the constraints are significantly improved. As an example, denoting xu as the Du coupling to the first and second generations, for $$ {M}_{D^u} $$

M

D
u

= 600 GeV, the low-energy constraint is |xu| ≤ 14.4, while the addition of the LHC dijet measurement leads to |xu| ≤ 0.13–0.15. Further improvements are obtained by adding the measurement of single top production with a pT cut. These new constraints must be taken into account in making predictions for other low-energy indirect effects of diquarks.
Drag force to all orders in gradients
Authors: Reiten Jared , Sadofyev Andrey V.
Published: July 2020

Abstract

We study the energy loss of a heavy quark slowly moving through an evolving strongly coupled plasma. We use the linearized fluid/gravity correspondence to describe small perturbations of the medium flow with general spacetime dependence. This all order linearized hydrodynamics results in a drag force exerted on a heavy quark even when it is at rest with the fluid element. We show how the general contribution to the drag force can be derived order by order in the medium velocity gradients and provide explicit results valid up to the third order. We then obtain an approximate semi-analytic result for the drag force to all orders in the gradient expansion but linearized in the medium velocity. Thus, the effects of a class of hydrodynamic gradients on the drag force are re-summed, giving further insight into the dissipative properties of strongly coupled plasmas. The all order result allows us to study the drag force in the non-hydrodynamic regime of linear medium perturbations that vary rapidly in space and time.
Medium-induced cascade in expanding media
Authors: Adhya Souvik Priyam , Salgado Carlos A. , Spousta Martin , Tywoniuk Konrad
Published: July 2020

Abstract

Detailed insight into the interplay between parton energy loss and the way deconfined medium created in heavy-ion collisions expands is of great importance for improving the understanding of the jet quenching phenomenon. In this paper we study the impact of the expansion of deconfined medium on the single-gluon emission spectrum, its resummation and the jet suppression factor (QAA) within the BDMPS-Z formalism. We calculate these quantities for three types of expansion scenarios, namely static, exponentially decaying and Bjorken expanding media. The distribution of medium-induced gluons is calculated using an evolution equation with splitting kernels derived from the gluon emission spectra. A universal behavior of splitting kernels is derived in the regime of soft gluon emissions when evaluated at a common effective evolution time τeff. Novel scaling features of the resulting gluon distribution and jet QAA are discussed. For realistic spectra valid beyond the soft-gluon emission limit, where the results are obtained by a numerical solution of the evolution equation, these features are partially replaced by a scaling expected from considering an averaged jet quenching parameter along the trajectory of propagation. Further we show that differences arising from different types of the medium expansion can be to a large extent scaled out by appropriate choice of the quenching parameter. Sizable differences among the values of the quenching parameter for different types of medium expansion point to the importance of the medium expansion for precise modeling of the jet quenching phenomenon.
Non-targeted and targeted analysis of oxylipins in combination with charge-switch derivatization by ion mobility high-resolution mass spectrometry
Authors: Hellhake Stefan , Meckelmann Sven W. , Empl Michael T. , Rentmeister Kristina , Wißdorf Walter , Steinberg Pablo , Schmitz Oliver J. , Benter Thorsten , Schebb Nils Helge
Published: July 2020

Eicosanoids and other oxylipins play an important role in mediating inflammation as well as other biological processes. For the investigation of their biological role(s), comprehensive analytical methods are necessary, which are able to provide reliable identification and quantification of these compounds in biological matrices. Using charge-switch derivatization with AMPP (N-(4-aminomethylphenyl)pyridinium chloride) in combination with liquid chromatography ion mobility quadrupole time-of-flight mass spectrometry (LC-IM-QTOF-MS), we developed a non-target approach to analyze oxylipins in plasma, serum, and cells. The developed workflow makes use of an ion mobility resolved fragmentation to pinpoint derivatized molecules based on the cleavage of AMPP, which yields two specific fragment ions. This allows a reliable identification of known and unknown eicosanoids and other oxylipins. We characterized the workflow using 52 different oxylipins and investigated their fragmentation patterns and ion mobilities. Limits of detection ranged between 0.2 and 10.0 nM (1.0–50 pg on column), which is comparable with other state-of-the-art methods using LC triple quadrupole (QqQ) MS. Moreover, we applied this strategy to analyze oxylipins in different biologically relevant matrices, as cultured cells, human plasma, and serum.
Spinal cord involvement in Kearns-Sayre syndrome: a neuroimaging study
Authors: Luca Pasquini , Alessia Guarnera , Camilla Rossi-Espagnet Maria , Antonio Napolitano , Diego Martinelli , Federica Deodato , Daria Diodato , Rosalba Carrozzo , Carlo Dionisi-Vici , Daniela Longo
Published: July 2020

Purpose

Spinal cord involvement in Kearns-Sayre (KSS) syndrome could be more frequent than commonly thought. Our aims were to evaluate the involvement of the spinal cord in patients with KSS by means of MRI and to investigate possible correlations of spinal and brain disease with patient disability.

Methods

Eleven patients with KSS disease and spinal cord MRI were retrospectively recruited. The severity of spinal disease was defined as follows: grade 0 (none), grade 1 (focal), and grade 2 (extensive). We calculated a radiologic score of brain involvement based on typical features. We performed a chi-square test to correlate spinal cord and brain MRI involvement to patient disability. For significant variables, a contingency coefficient, phi factor, and Cramer’s V were also computed.

Results

Spinal cord lesions were detected in 6/11 patients, showing four patterns: involvement of gray matter, gray matter and posterior columns, posterior columns, and anterior columns. The severity of spinal disease was grade 1 in two and grade 2 in four patients. All patients showed brain involvement (9-point average for patients with spinal involvement and 10 for the others). A significant correlation was found between disability score and spinal cord involvement (χ2 = 7.64; p = 0.022) or brain score (χ2 = 26.85; p = 0.043). Significance for brain score-disability correlation increased with the spinal cord as a cofactor (χ2 = 24.51; p = 0.017, phi factor = 1.201, Cramer’s V = 0.849, contingency effect = 0.767; p = 0.017).

Conclusion

Spinal cord lesions are common in KSS. Patients with spinal disease show higher disability than patients without spinal cord lesions, supporting the inclusion of dedicated acquisitions to routine MRI of the brain in patients with KSS.
Kigali Surgical Sepsis (KiSS) Score: A New Tool to Predict Outcomes in Surgical Patients with Sepsis in Low‐ and Middle‐Income Settings
Authors: Niyongombwa Irénée , Sibomana Isaie , Karenzi Irénée D. , Kiswezi Ahmed , Rickard Jennifer
Published: July 2020

Background

Sepsis is common in surgical patients, and its presence influences the outcomes in those to undergo surgery. Factors such as advanced age, presence of comorbidities and many other conditions increase mortality in surgical patients with sepsis. The sequential organ failure assessment (SOFA) score simplified into qSOFA helps to define sepsis and to identify patients who are likely to die from it. Sepsis in surgery is under investigated in low‐ and middle‐income countries and so are the factors for mortality in that specific surgical population. Our aim was to develop a prognostic tool accurate in predicting outcomes in surgical patients with sepsis who present at University Teaching Hospitals of Kigali (CHUK) and Butare (CHUB) and in other centers with limited resources

Methods

This was a prospective cohort study conducted over a period of 1 year from February 2018 to January 2019. The surgical patients with sepsis recruited in the first 6 months at CHUK served as the derivation cohort and those recruited in the next 6 months from both CHUK and CHUB served as the validation cohort. The Kigali surgical sepsis (KiSS) score was derived, and to determine its accuracy in predicting mortality, we measured sensitivity, specificity and area under receiver operator characteristic (AUROC) curve. We then compared this with qSOFA score.

Results

A total of 288 patients were recruited with 144 in each cohort. The mean age was 36.5, and median age was 32.6. The mean length of hospital stay (LoHS) was 22.9 days. The overall intensive care unit (ICU) admission rate was 51.4%, and the surgical sepsis‐related hospital mortality rate was 21.7%. Factors associated with surgical sepsis‐related hospital mortality were age above 55 years (p = 0.034), presence of comorbidities (p = 0.069), hypotension (p = 0.014), tachycardia (p = 0.061), tachypnea (p = 0.028), decreased level of consciousness (p = 0.021), presence of GIT perforation (p = 0.026) and number of impaired organ function (p = 0.035). A predictive score (KiSS score) consisting of six parameters was derived from these factors and compared to qSOFA score. The sensitivity of KiSS score in predicting mortality was 73% (vs 52% for qSOFA), and the specificity was 97% (vs 87% for qSOFA). The predictive validity for hospital mortality was assessed by AUROC curve, and it was 0.939 (95% CI, p < 0.001) for KiSS and 0.684 (95% CI, p < 0.001) for qSOFA.

Conclusion

The KiSS score was effective in predicting surgical sepsis‐related hospital mortality in low‐resource setting. The KiSS score showed an added advantage of stratifying septic surgical patients to be operated on into those with good, variable and poor prognosis.
Towards reference values of pericoronary adipose tissue attenuation: impact of coronary artery and tube voltage in coronary computed tomography angiography
Authors: Ma Runlei , Ties Daan , van Assen Marly , Pelgrim Gert Jan , Sidorenkov Grigory , van Ooijen Peter M. A. , van der Harst Pim , van Dijk Randy , Vliegenthart Rozemarijn
Published: July 2020

Objectives

To determine normal pericoronary adipose tissue mean attenuation (PCATMA) values for left the anterior descending (LAD), left circumflex (LCX), and right coronary artery (RCA) in patients without plaques on coronary CT angiography (cCTA), taking into account tube voltage influence.

Methods

This retrospective study included 192 patients (76 (39.6%) men; median age 49 years (range, 19–79)) who underwent cCTA with third-generation dual-source CT for the suspicion of CAD between 2015 and 2017. We selected patients without plaque on cCTA. PCATMA was measured semi-automatically on cCTA images in the proximal segment of the three main coronary arteries with 10 mm length. Paired t-testing was used to compare PCATMA between combinations of two coronary arteries within each patient, and one-way ANOVA testing was used to compare PCATMA in different kV groups.

Results

The overall mean ± standard deviation (SD) PCATMA was − 90.3 ± 11.1 HU. PCATMA in men was higher than that in women: − 88.5 ± 10.5 HU versus − 91.5 ± 11.3 HU (p = 0.001). PCATMA of LAD, LCX, and RCA was − 92.4 ± 11.6 HU, − 88.4 ± 9.9 HU, and − 90.2 ± 11.4 HU, respectively. Pairwise comparison of the arteries showed significant difference in PCATMA: LAD and LCX (p < 0.001), LAD and RCA (p = 0.009), LCX and RCA (p = 0.033). PCATMA of the 70 kV, 80 kV, 90 kV, 100 kV, and 120 kV groups was − 95.6 ± 9.6 HU, − 90.2 ± 11.5 HU, − 87.3 ± 9.9 HU, − 82.7 ± 6.2 HU, and − 79.3 ± 6.8 HU, respectively (p < 0.001).

Conclusions

In patients without plaque on cCTA, PCATMA varied by tube voltage, with minor differences in PCATMA between coronary arteries (LAD, LCX, RCA). PCATMA values need to be interpreted taking into account tube voltage setting.

Key Points

• In patients without plaque on cCTA, PCATMAdiffers slightly by coronary artery (LAD, LCX, RCA).

• Tube voltage of cCTA affects PCATMAmeasurement, with mean PCATMAincreasing linearly with increasing kV.

• For longitudinal cCTA analysis of PCATMA, the use of equal kV setting is strongly recommended.
Deep learning for the rapid automatic quantification and characterization of rotator cuff muscle degeneration from shoulder CT datasets
Authors: Taghizadeh Elham , Truffer Oskar , Becce Fabio , Eminian Sylvain , Gidoin Stacey , Terrier Alexandre , Farron Alain , Büchler Philippe
Published: July 2020

Objectives

This study aimed at developing a convolutional neural network (CNN) able to automatically quantify and characterize the level of degeneration of rotator cuff (RC) muscles from shoulder CT images including muscle atrophy and fatty infiltration.

Methods

One hundred three shoulder CT scans from 95 patients with primary glenohumeral osteoarthritis undergoing anatomical total shoulder arthroplasty were retrospectively retrieved. Three independent radiologists manually segmented the premorbid boundaries of all four RC muscles on standardized sagittal-oblique CT sections. This premorbid muscle segmentation was further automatically predicted using a CNN. Automatically predicted premorbid segmentations were then used to quantify the ratio of muscle atrophy, fatty infiltration, secondary bone formation, and overall muscle degeneration. These muscle parameters were compared with measures obtained manually by human raters.

Results

Average Dice similarity coefficients for muscle segmentations obtained automatically with the CNN (88% ± 9%) and manually by human raters (89% ± 6%) were comparable. No significant differences were observed for the subscapularis, supraspinatus, and teres minor muscles (p > 0.120), whereas Dice coefficients of the automatic segmentation were significantly higher for the infraspinatus (p < 0.012). The automatic approach was able to provide good–very good estimates of muscle atrophy (R2 = 0.87), fatty infiltration (R2 = 0.91), and overall muscle degeneration (R2 = 0.91). However, CNN-derived segmentations showed a higher variability in quantifying secondary bone formation (R2 = 0.61) than human raters (R2 = 0.87).

Conclusions

Deep learning provides a rapid and reliable automatic quantification of RC muscle atrophy, fatty infiltration, and overall muscle degeneration directly from preoperative shoulder CT scans of osteoarthritic patients, with an accuracy comparable with that of human raters.

Key Points

• Deep learning can not only segment RC muscles currently available in CT images but also learn their pre-existing locations and shapes from invariant anatomical structures visible on CT sections.

• Our automatic method is able to provide a rapid and reliable quantification of RC muscle atrophy and fatty infiltration from conventional shoulder CT scans.

• The accuracy of our automatic quantitative technique is comparable with that of human raters.
The biological basis and function of GNAS mutation in pseudomyxoma peritonei: a review
Authors: Lin Yu-Lin , Ma Ru , Li Yan
Published: July 2020

Purpose

Pseudomyxoma peritonei (PMP) is a rare clinical malignancy syndrome characterized by the uncontrollable accumulation of copious mucinous ascites in the peritoneal cavity, resulting in “jelly belly”. The mechanism of tumor progression and mucin hypersecretion remains largely unknown, but GNAS mutation is a promising contributor. This review is to systemically summarize the biological background and variant features of GNAS, as well as the impacts of GNAS mutations on mucin expression, tumor cell proliferation, clinical-pathological characteristics, and prognosis of PMP.

Methods

NCBI PubMed database (in English) and WAN FANG DATA (in Chinese) were used for literature search. And NCBI Gene and Protein databases, Ensembl Genome Browser, COSMIC, UniProt, and RCSB PDB database were used for gene and protein review.

Results

GNAS encodes guanine nucleotide-binding protein α subunit (Gsα). The mutation sites of GNAS mutation in PMP are relatively stable, usually at Chr20: 57,484,420 (base pair: C-G) and Chr20: 57,484,421 (base pair: G-C). Typical GNAS mutation results in the reduction of GTP enzyme activity in Gsα, causing failure to hydrolyze GTP and release phosphoric acid, and eventually the continuous binding of GTP to Gsα. The activated Gsα could thus continuously promote mucin secretion through stimulating the cAMP-PKA signaling pathway, which is a possible mechanism leading to elevated mucin secretion in PMP.

Conclusion

GNAS mutation is one of the most important molecular biological features in PMP, with major functions to promote mucin hypersecretion.
Discrete uniform and binomial distributions with infinite support
Authors: Pepelyshev Andrey , Zhigljavsky Anatoly
Published: July 2020

We study properties of two probability distributions defined on the infinite set$$\{0,1,2, \ldots \}$${0,1,2,…}and generalizing the ordinary discrete uniform and binomial distributions. Both extensions use the grossone-model of infinity. The first of the two distributions we study is uniform and assigns masses$$1/\textcircled {1}$$1/1to all points in the set$$ \{0,1,\ldots ,\textcircled {1}-1\}$${0,1,…,1-1}, where$$\textcircled {1}$$1denotes the grossone. For this distribution, we study the problem of decomposing a random variable$$\xi $$ξwith this distribution as a sum$$\xi {\mathop {=}\limits ^\mathrm{d}} \xi _1 + \cdots + \xi _m$$ξ=dξ1+⋯+ξm, where$$\xi _1 , \ldots , \xi _m$$ξ1,…,ξmare independent non-degenerate random variables. Then, we develop an approximation for the probability mass function of the binomial distribution Bin$$(\textcircled {1},p)$$(1,p)with$$p=c/\textcircled {1}^{\alpha }$$p=c/1αwith$$1/2<\alpha \le 1$$1/2<α≤1. The accuracy of this approximation is assessed using a numerical study.
What happened to financially sustainable firms in the Corona crisis?
Authors: Günther Thomas , Gleißner Werner , Walkshäusl Christian
Published: July 2020

Purpose: Financial sustainability is underrepresented in both research on and the practice of sustainability management and reporting. In this article, we examine empirically how financially sustainable firms performed in the Corona crisis.

Methods: We measure financial sustainability by four conditions: (1) firm growth, (2) the company’s ability to survive, (3) an acceptable overall level of earnings risk exposure, and (4) an attractive earnings risk profile. We apply this measurement to investment portfolios of a broad sample of firms from 15 European countries of the MSCI Europe using typical investment portfolio characteristics.

Results: We find that financially sustainable firms outperform both the broad market and firms with low financial sustainability for the time span July 2019 to March 2020.

Conclusion: An investment strategy that invests in financially sustainable firms seems to be better capable of overcoming economic breakdowns such as the Corona crisis. We find that the returns increase with each of the four conditions that are included in the investment strategy. This underlines that considering financial sustainability is interesting for financial management, corporate governance and management control.
Genetic diversity and evolutionary history of Korean isolates of severe fever with thrombocytopenia syndrome virus from 2013–2016
Authors: Yun Mi-ran , Ryou Jungsang , Choi Wooyoung , Lee Joo-Yeon , Park Sun-Whan , Kim Dae-Won
Published: July 2020

Severe fever with thrombocytopenia syndrome (SFTS) is caused by SFTS virus (SFTSV). Although SFTS originated in China, it is an emerging infectious disease with prevalence confirmed in Japan, Korea, and Vietnam. The full-length genomes of 51 Korean SFTSV isolates from 2013 to 2016 were sequenced, and the sequences were deposited into a public database (GenBank) and analyzed to elucidate the phylogeny and evolution of the virus. Although most of the Korean SFTSV isolates were closely related to previously reported Japanese isolates, some were closely related to previously reported Chinese isolates. We identified one Korean strain that appears to have resulted from multiple inter-lineage reassortments. Several nucleotide and amino acid variations specific to the Korean isolates were identified. Future studies should focus on how these variations affect virus pathogenicity and evolution.
Robust requirements gathering for ontologies in smart water systems
Authors: Howell Shaun , Beach Thomas , Rezgui Yacine
Published: July 2020

Urban environments are urgently required to become smarter to overcome sustainability and resilience challenges whilst remaining economically viable. This involves a vast increase in the penetration of ICT resources, both physical and virtual, with the requirement to factor in built environment, socio-economic and human artefacts. This paper, therefore, proposes a methodology for eliciting, testing, and deploying, requirements in the field of urban cybernetics. This extends best practice requirements engineering principles to meet the demands of this growing niche. The paper follows a case study approach of applying the methodology in the smart water domain, where it achieves positive results. The approach not only heavily utilises iteration alongside domain experts, but also mandates the integration of technical domain experts to ensure software requirements are met. A key novelty of the approach is prioritising a balance between (a) knowledge engineers’ tenacity for logical accuracy, (b) software engineers’ need for speed, simplicity, and integration with other components, and (c) the domain experts’ needs to invoke ownership and hence nurture adoption of the resulting ontology.
Microscopy of Metal Oxide Surfaces
Authors: Castell Martin R. , Dudarev Sergei L. , Muggelberg Christiane , Sutton Adrian P. , Briggs G. Andrew D. , Goddard David T.
Published: July 2020

Elevated temperature scanning tunneling microscopy is used to study
oxides that are room temperature insulators but become sufficiently
electrically conducting at higher temperatures to allow imaging to be
performed. Atomic resolution images of NiO, CoO, and
UO2 have been obtained in this fashion which allow
surface structure and defect determination. To complement the experiments,
modeling of the electronic surface structure reveals which atomic sites give
rise to the contrast observed in the images. Low voltage scanning electron
microscopy is used to image small equilibrium pores in
UO2 single crystals to evaluate the surface energy
ratio of the (111) to (001) surfaces.
Field Emission and Electron Microscopy
Authors: Edgcombe Christopher John , Valdrè Ugo
Published: July 2020

An overview and new results are presented of the investigations carried
out in the last 5 years on nano-sized tips by means of electron microscopy,
an electron optical bench, and computation. Tungsten and, in particular,
carbon nano-tips prepared by carbon contamination in a scanning electron
microscope, were studied for applications as field-emission electron
sources. Several features of their use are described and the results
concerning the determination of some of their basic properties are
reported.
Extended and Point Defects in Diamond Studied with the Aid of Various
Forms of Microscopy
Authors: Steeds John W. , Charles Steven J. , Gilmore Annette C. , Butler James E.
Published: July 2020

It is shown that star disclinations can be a significant source of
stress in chemical vapor deposited (CVD) diamond. This purely geometrical
origin contrasts with other sources of stress that have been proposed
previously. The effectiveness is demonstrated of the use of electron
irradiation using a transmission electron microscope (TEM) to displace atoms
from their equilibrium sites to investigate intrinsic defects and impurities
in CVD diamond. After irradiation, the samples are studied by low
temperature photoluminescence microscopy using UV or blue laser
illumination. Results are given that are interpreted as arising from
isolated <100> split self-interstitials and positively charged single
vacancies. Negatively charged single vacancies can also be revealed by this
technique. Nitrogen and boron impurities may also be studied similarly. In
addition, a newly developed liquid gallium source scanned ion beam mass
spectrometry (SIMS) instrument has been used to map out the B distribution
in B doped CVD diamond specimens. The results are supported by micro-Raman
spectroscopy.
Inferring Physical Parameters from Images of Vibrating Carbon
Nanotubes
Authors: Treacy M.M.J. , Krishnan A. , Yianilos P.N.
Published: July 2020

We describe a hidden parameter inferencing algorithm for deducing the
length, width, and vibration profile from images of thermally excited
single-wall carbon nanotubes. With accurate estimates of these parameters,
the Young’s modulus can be deduced. The algorithm is sensitive to shot noise
in the image, primarily because of the low nanotube image contrast. Noise
causes the nanotube length and width to be overestimated, and the vibration
amplitude to be underestimated. After correcting for shot noise, we infer an
average value of the Young’s modulus of 〈Y〉= 1.20±0.20 TPa, which is larger
than the currently accepted value for graphite.
Transmission Electron Diffraction at 200 eV and Damage Thresholds below
the Carbon K Edge
Authors: Stevens Michael R. , Chen Qing , Weierstall Uwe , Spence John C.H.
Published: July 2020

Transmission electron diffraction patterns from ultra-thin aromatic and
aliphatic organic films at beam energies of 200 eV–1 keV have been recorded
in a custom low energy electron transmission (LEET) chamber. A significant
reduction of the molecular damage cross-section, measured by fading of
diffraction spots, was found for thin films of the aromatic perylene when
the beam energy was reduced from 400 to 200 eV. The corresponding
measurements for the aliphatic tetracontane showed a smaller “threshold
energy” and the differences are discussed. Electron beam damage from other
aromatic materials has also been studied at low energy. Comparison of the
carbon K shell ionization cross-section and the measured damage
cross-sections show that carbon K-shell ionization is strongly correlated
with the damage observed in aromatics at beam energies higher than 284 eV.
Calculation of the minimum number of unit cells needed for imaging a single
molecule, and comparison of calculated elastic with measured damage
cross-sections both indicate new possibilities for imaging biomolecules with
low energy electrons.
Threshold Energy Effects in Secondary Electron Emission
Authors: Howie A.
Published: July 2020

In large bandgap semiconductors and insulators, the threshold energies
for e–h pair production and ionization damage can lie above the vacuum
level. For low energy imaging, a window is then opened whose width is
potentially sensitive to local changes in work function, doping level, or
acidity. Recent progress and future opportunities for damage-free imaging of
these properties using low energy electrons are discussed in the light of
the underlying physics, as well as of recent instrumental developments in
low energy electron microscopy (LEEM), environmental scanning electron
microscopy (ESEM), photoelectron emission microscopy (PEEM), scanned probe
microscopy (SPM), and projection electron microscopy.
Rapid and Semi-automated Method for Analysis of the Number of Atoms of
Ultra-small Platinum Clusters on Carbon
Authors: Yang J.C. , Bradley S. , Gibson J.M.
Published: July 2020

Very high angle (~100 mrad) annular dark-field (HAADF) images in a
dedicated scanning transmission electron microscope (STEM) can be used to
quantitatively measure the number of atoms in a cluster on a support
material. We have developed a computer program which will automatically find
the location of the particles and then integrate the intensity to find the
number of atoms per cluster. We have examined ultra-small Pt clusters on a C
substrate by this novel mass-spectroscopic technique. We discovered that the
Pt clusters maintain their three-dimensional shape, and are probably
spherical.
Z-contrast Imaging in an Aberration-corrected Scanning Transmission
Electron Microscope
Authors: Pennycook S.J. , Rafferty B. , Nellist P.D.
Published: July 2020

We show that in the limit of a large objective (probe-forming) aperture,
relevant to a spherical aberration corrected microscope, the Z-contrast
image of a zone-axis crystal becomes an image of the 1s Bloch states. The
limiting resolution is therefore the width of the Bloch states, which may be
greater than that of the free probe. Nevertheless, enormous gains in image
quality are expected from the improved contrast and signal-to-noise ratio.
We present an analytical channeling model for the thickness dependence of
the Z-contrast image in a zone-axis crystal, and show that, at large
thicknesses, columnar intensities become proportional to the mean square
atomic number, Z2.
Reverse Flow Pressure Limiting Aperture
Authors: Danilatos Gerasimos D.
Published: July 2020

The reverse flow pressure limiting aperture is a device that creates and
sustains a substantial gas pressure difference between two chambers
connected via an aperture. The aperture is surrounded by an annular orifice
leading to a third chamber. The third chamber is maintained at a relatively
high pressure that forces gas to flow through the annular aperture into the
first of said two chambers. The ensuing gas flow develops into a supersonic
annular gas jet, the core of which is coaxial with the central aperture. A
pumping action is created at the core of the jet and any gas molecules
leaking through the aperture from the second chamber are entrained and
forced into the first chamber, thus creating a substantial pressure
difference between the first and second chamber.
Nanomeasurements in Transmission Electron Microscopy
Authors: Wang Z.L. , Poncharal P. , de Heer W.A.
Published: July 2020

Nanomaterials have attracted a great deal of research interest recently.
The small size of nanostructures constrains the applications of
well-established testing and measurement techniques, thus new methods and
approaches must be developed for quantitative measurement of the properties
of individual nanostructures. This article reports our progress in using in
situ transmission electron microscopy to measure the electrical, mechanical,
and field-emission properties of individual carbon nanotubes whose
microstructure is well-characterized. The bending modulus of a single carbon
nanotube has been measured by an electric field-induced resonance effect. A
nanobalance technique is demonstrated that can be applied to measure the
mass of a tiny particle as light as 22 fg (1 fg = 10−15
g), the smallest balance in the world. Quantum conductance was observed in
defect-free nanotubes, which led to the transport of a superhigh current
density at room temperature without heat dissipation. Finally, the
field-emission properties of a single carbon nanotube are observed, and the
field-induced structural damage is reported.
Fiber-optic Based Spectral Cathodoluminescence: Simple and Economic
Option for Use in Conventional and Environmental Scanning Electron
Microscopy
Authors: Griffin Brendan J. , Browne James R.
Published: July 2020

A fiber-optic based spectral cathodoluminescence (CL) system has been
successfully installed on a variable pressure “environmental” scanning
electron microscope (ESEM). The fine size of the fiber (50 μm) has been
found to require careful alignment. To provide this alignment, a simple X–Y
translator has been used. The aligned fiber exhibits high efficiency and the
system has recorded spectra at up to 3 million “counts” per sec on strongly
cathodoluminescent doped yttrium aluminium garnet (YAG) samples, at 30 kV
and ˜3 nA. A resolution of 3 nm [full width half maximum (FWHM)] at 621 nm
has been measured from a red laser diode spectrum, on the ESEM column. A
range of uncoated materials has been measured to characterize the CL system;
these materials ranged from strongly luminescent YAG to weakly luminescent
polymers. Wellcharacterized doped zircons have also been investigated. These
data suggest that the previously reported intrinsic peak from zircon is a
consequence of high-beam currents.
Correlation between Charge Contrast Imaging and the Distribution of Some
Trace Level Impurities in Gibbsite
Authors: Baroni Travis C. , Griffin Brendan J. , Browne James R. , Lincoln Frank J.
Published: July 2020

Charge contrast images (CCI) of synthetic gibbsite obtained on an
environmental scanning electron microscope gives information on the
crystallization process. Furthermore, X-ray mapping of the same grains shows
that impurities are localized during the initial stages of growth and that
the resulting composition images have features similar to these observed in
CCI. This suggests a possible correlation between impurity distributions and
the emission detected during CCI. X-ray line profiles, simulating the
spatial distribution of impurities derived from the Monte Carlo program
CASINO, have been compared with experimental line profiles and give an
estimate of the localization. The model suggests that a main impurity, Ca,
is depleted from the solution within approximately 3–4 μm of
growth.
Compression of Secondary Ion Microscopy Image Sets Using a
Three-dimensional Wavelet Transformation
Authors: Wolkenstein Martin G. , Hutter Herbert
Published: July 2020

This article proposes a lossy three-dimensional (3-D) image compression
method for 3-D secondary ion microscopy (SIMS) image sets that uses a
separable nonuniform 3-D wavelet transform. A typical 3-D SIMS measurement
produces relatively large amounts of data which has to be reduced for
archivation purposes. Although it is possible to compress an image set slice
by slice, more efficient compression can be achieved by exploring the
correlation between slices. Compared to different two-dimensional (2-D)
image compression methods, compression ratios of the 3-D wavelet method are
about four times higher at a comparable peak signal-to-noise ratio
(PSNR).
Cross-sectional Specimen Preparation and Observation of a Plasma Sprayed
Coating Using a Focused Ion Beam/Transmission Electron Microscopy
System
Authors: Yaguchi Toshie , Kamino Takeo , Sasaki Mitsumasa , Barbezat Gerard , Urao Ryoichi
Published: July 2020

A focused ion beam (FIB) technique was applied to cross-sectional
specimen preparation to observe an interface between a plasma sprayed
coating and an aluminum (Al) substrate by transmission electron microscopy
(TEM). The surface of the sprayed coating film has a roughness of several
tens of microns. Sputter rates for the coating film and the substrate are
greatly different. The rough surface and the difference in sputter rate
cause problems in making TEM specimens with smooth side walls. The top
surface of the coating film was planerized by the FIB before fabricating the
TEM specimen. The interfaces were investigated by TEM and energy-dispersive
X-ray (EDX) analysis. The TEM observation revealed that there is a 10 nm
thick amorphous layer at the interface between the coating film and
substrate. The coating film consists of two kinds of sublayers with bright
and dark contrast. The bright contrast sublayers were amorphous layers with
thickness of 2~10 nm. The Al/Fe X-ray intensity ratio was larger in bright
contrast sublayers than that in dark contrast sublayers.
New Technique for Successful Thermal Barrier Coating Specimen Preparation
for Transmission Electron Microscopy
Authors: Brickey M.R. , Lee J.L.
Published: July 2020

Reliability of thermal barrier coatings (TBC) hinges on the adhesion of
a thermally grown oxide scale to an insulative ceramic topcoat and an
underlying metallic bondcoat. The width of the scale and its interfaces
makes transmission electron microscopy (TEM) an appropriate tool for its
analysis. However, specimen preparation has proven to be a challenging
obstacle leading to a dearth of TEM research on TBCs. A new approach to
cross-section TBC TEM specimen preparation is described. The principal
advantages of this technique are reproducibility, reduced specimen damage,
and time savings resulting from decreased ion milling. This technique has
been successfully applied to numerous TBC specimens with various thermal
histories.
Endovascular treatment of ischemic large-vessel stroke due to infective endocarditis: case series and review of the literature
Authors: D’Anna Lucio
Published: July 2020

Background

Mechanical thrombectomy is the standard of care, in selected patients, for acute ischemic stroke with large vessel occlusion but its use in patients with stroke secondary to infective endocarditis is controversial. We report three cases of acute ischemic stroke treated by mechanical thrombectomy and we propose an extensive review of the literature to evaluate the clinical safety and efficacy of thrombectomy in patients with stroke secondary to infective endocarditis.

Methods

A comprehensive literature search was performed following a pre-specified protocol of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Case reports, cases series, cross-sectional studies, case control studies, randomized controlled trials or nonrandomized controlled trials were considered that included endocarditis-related acute ischemic stroke patients who underwent mechanical thrombectomy.

Results

The database search yielded 431 relevant records published until January 2020. Nineteen articles fulfilled the eligibility criteria that described thirty patients. After the thrombectomy, 13.3% of the patients experienced intracranial haemorrhage. After the procedure, the median National Institutes of Health Stroke Scale score dropped from 15 (IQR 7) to 2.5 (IQR 5.75). At 90 days, mortality was 23.3% while 46.7% of the patients were functionally independent (mRS ≤ 2).

Discussion

Based on our review, the use of mechanical thrombectomy in patients with large vessel occlusion due to endocarditis-associated stroke might improve patient outcome but it should be considered on a case by case base as the safety has not been well established yet. Further research on risk stratification is needed to drive clinician during the decision-making process.