bluuebunny/crossref_metadata_2025 huggingface dataset:
Recovery of valuable heavy minerals via gravity and magnetic separation operations from Diit Quaternary stream sediments, southern coast of the Red Sea, Egypt
Authors: Fawzy M M , Abu El Ghar M S , Gaafar I M , El Shafey A M , Diab M , Hussein A W
Published: August 2022

This research aims to concentrate and recover valuable heavy minerals (VHMs) contained in Diit area, southern coast of the Red Sea, Egypt. In this study, three technological samples were collected representing Lens, Delta and Wadi Diit; mineralogical investigation followed by mineral processing was performed in order to recover VHM content. VHMs such as zircon, ilmenite, rutile, sphene, apatite, garnet, and magnetite have been recorded in associations with lesser amounts of uranothorite, monazite, xenotime, fergusonite, khatyrkite, and gold. Initially, two stage wet gravity concentration processes, rougher and scavenger, were carried out via a shaking table to produce a clean concentrate of VHMs, which was used as feed material for the magnetic separation process. Magnetic separation was performed in order to separate ferromagnetic minerals from paramagnetic minerals as well as diamagnetic minerals to obtain clean concentration of these fractions. Assay and Material balance of the concentration steps proved that the THM content of Diit lens increased to 89.70% with a recovery of 91.68% in a weight of 61.08% out of the original sample. While the percentage of THM content in Wadi and Delta Diit samples increased to 48.68 and 47.67% respectively, with recovery equivalent to 71.67 and 82.06% respectively in a weight of 16.51, 18.7% respectively out of the original sample. Finally, a process flowsheet was created according to the optimum conditions for concentration and separation processes.
Thermal behavior and explosive properties of TNT/RGO
Authors: Talaat Ahmed , Elbeih Ahmed , Tantawy Hesham , Hussein Ahmed K.
Published: August 2022

2,4,6-trinitrotoluene (TNT), is the most widely accessible explosive. Thanks to the melt cast characteristics (melting temperature of TNT is 80-82 °C,), lead to contribute in many applications as mortars, grenades, artillery rounds, warheads, and antipersonnel mines. TNT has high chemical stability, and moderate sensitivity. In this paper, a novel addition of nano particles of reduced graphene oxide (RGO) was added to enhance the TNT characteristics. A composite TNT/RGO 98:2 wt. % was prepared. The morphology of the composite mixture was captured using scanning electron microscopy (SEM). Impact sensitivity and friction sensitivity were evaluated, thermal behavior was investigated using diffeential scanning calorimetry (DSC), the characterization of the prepared composite and pure TNT was examined using an X-Ray diffractometer. Explosive characteristics were determined by detonation velocity and brisance by Kast . The results showed improvement in the sensitivity with reserving the high explosive characteristics of TNT. Interestingly, a decrease in the melting point of TNT due to the presence of RGO in the composite was observed. This addition might be an effective parameter in the melting procedure of TNT.
Comparative Studies on Hydrometallurgy and Pyrometallurgy to the Extraction of Beryllium from Decrepitated Beryl from Wadi El Gemal Region, Eastern Desert, Egypt
Authors: Atrees Mohamed Shabaan , Mira Hamed I. E. , Kawassik Yasser M , Ali Mohamed E. M.
Published: August 2022

Comparative Studies on hydrometallurgy and pyrometallurgy to the extraction of beryllium from decrepitated beryl from Wadi El Gemal Region, Eastern Desert, Egypt are carried out in this work in short, useful summary. Beryl is one of the important ore mineral constituents of the mineralized zones at Wadi El Gemal area, Eastern Desert, Egypt. Extraction of beryllium from beryl ore involves both (a) pyrometallurgical techniques through roasting of beryl with Na2SiF6 followed by leaching of roasting beryl with commercial (dilute) H2SO4 (b) hydrometallurgical processing techniques of beryl through direct leaching with H2SO4 to produce directly sulfate liquor. 88% of beryllium was extracted by roasted beryl with Na2SiF6 at 850°C for 1.5 hours and leaching the roasted product with 25% H2SO4 AT 85 ° C for 3/4 hour. On the other hand, 95 % of beryllium was extracted directly after 20 minutes by direct leaching at 280°c with 10 mol/liter H2SO4. Therefore, this work sheds light on the study of the factors affecting both forms of beryllium extraction.
Waste Cooking Oil Management in Egypt: Production of Biodiesel-Development of Rapid Test Method
Authors: Mohamed Marwa , Sherif Nourhan , Aboelazayem Omar , Elazab Hany A. , Gadalla Mamdouh , Saha Basudeb
Published: August 2022

According to the United Nations Office for South-South Cooperation (UNOSSC) report in 2017, Egypt produced 500,000 tonnes of WCO from various resources including food industries, restaurants and hotels. Based on our previous funded project, we have reported unique properties for Egyptian WCO as it has very high range acidity (≈18 mg KOH/ g oil) due to the extensive usage of oil in the cooking process. Further, the repeated heating of cooking oil for long time produces carcinogenic compounds that have significant impact on people health. On the other hand, high acidity WCO could be valorised into soap, biodiesel and value added chemicals. However, most of these industries requires costly pre-treatment for the WCO to reduce the acidity prior processing. Accordingly, the WCO should be produced within a guideline of specified properties that could detect if it has been extensively used. Low-acidity WCO will prevent several health consequences for Egyptian people and allow industries to easily valorise it into value added chemicals and fuels. The waste cooking oil was subjected to filtration before being fed to the reactor the produced biodiesel was treated to remove any methanol and the characteristics of the final product was compared with the international standards. This work develops a guideline for WCO quality testing to ensure that it has not been extensively used in cooking process. The work also applies supercritical conditions to convert WCO into biodiesel. The response surface methodology was used to conclude the optimum conditions to produce biodiesel.
Implementing Nanocomposite Shear Thickening Fluid to Improve The Impact Resistance of Polyamide Fabrics Against Intermediate Velocity Projectiles
Authors: Mankarious Remon A , Radwan Mostafa A , Roushdy M H
Published: August 2022

The novelty of this research is the synthesis and comparison of a soft liquid composite shield made from two different Shear Thickening Fluids (STFs) / Polyamide fabric composite material and choosing the best one for impact resistance based on characterization and performance. The STFs microstructural properties are characterized, and STF / Polyamide composites are prepared while testing their ballistic resistance using an air gun with intermediate velocities (<100 m/s) for energy absorption. Materials used for this purpose are fumed silica with polyethylene glycol (PEG) STF and starch with water STF based dispersions. The results confirmed the superior performance of STF to absorb energy, especially for starch and water system. The rheological properties for starch/water STF showed higher viscosity than silica/PEG reaching 523.6 Pa.s and 178.9 Pa.s respectively. Other characterization tests proved the superior performance of starch with water STF leading to more dispersion stability and obvious thickening effect at higher particle concentration leading to a greater jump in viscosity at sudden shear rate. The highest concentration of silica/PEG STF/fabric showed improvement in indentation depth by 26.9%, while the starch/water STF by 43.6%. These results show the viability of the STF/Polyamide composite material if integrated for personal protection applications.
Impurity effects on Bogoliubov Fermi surfaces: A comparison with conventional BCS pairing
Authors: Hoshino Shintaro , Miki Tatsuya
Published: August 2022

The superconductors can have a Fermi surface even below the transition temperature, which is known as the Bogoliubov Fermi surface. Focusing on the degrees of freedom at low energies, which are described by the spinless Bogoliubov particles for the case without time-reversal symmetry, we consider the self-energy from the impurity scattering on the Bogoliubov Fermi surfaces. The physical quantities such as the density of states are evaluated based on the single-particle Green’s functions. We systematically compare these results with those of the conventional s-wave spin-singlet pairing state, to illuminate the characteristic features of the Bogoliubov particles located at the Fermi level.
Crystal structure and superconductivity of NaAlSi1–x
Ge
x
single crystals
Authors: Yamada Takahiro , Hirai Daigorou , Ikenobe Toshiya , Yamane Hisanori , Hiroi Zenji
Published: August 2022

NaAlSi and NaAlGe are nodal-line semimetals with an anti-PbFCl type structure. The former is a superconductor with a transition temperature Tc
of 7 K, while the latter does not exhibit superconductivity. We prepared single crystals of solid solution NaAlSi1–x
Ge
x
by the Na–Ga flux method and investigated their crystal structures and superconductivity by X-ray structural analysis and magnetization measurements, respectively. The crystal structure parameters vary continuously with x, while the Tc
initially decreases gradually from 6.9 K for x = 0 to 5.6 K for x = 0.33 and then decreases rapidly to below 1.8 K for x = 0.45. This sudden variation in Tc
at x ~ 0.4 may not be explained by the decrease in phonon frequency due to the Ge substitution, but suggests an unusual change in the electronic structure, in spite that the calculated band structures of the end members are almost identical with nearly equal density of states.
75As NMR studies on iron-based La1111 superconductors in lightly and heavily electron doped states
Authors: Kouchi T , Yoshinaga K , Nishioka S , Shiota T , Yashima M , Mukuda H , Kuroki K , Miyasaka S , Tajima S
Published: August 2022

We report 75As NMR experiments in heavily electron-doped LaFePnO0.75H0.25 (Pn=As1−x
Sb
x
and As1−x′
P
x′
) compounds with the maximum

T
c

max

(
∼
33.1
K
)

, and compare with the previous results in lightly electron-doped LaFePn(O,F) compounds. The Tc
of this series can be sensitively controlled by the pnictogen height (hPn
) through the substitution at Pn site, and the electron doping level through the substitution at the O site with H or F. In heavily electron-doped LaFePnO(La1111) compounds, we found that spin fluctuations at low-energies were moderately suppressed upon cooling in the Sb-substituted high Tc
compounds with high hPn
(x ≥ 0), although they are completely suppressed in P-substituted non-superconducting compounds (x′ ≥ 0.2) with lower hPn
. This feature is largely different from that in the lightly doped La1111 compounds with the well-nested Fermi surfaces, where the spin fluctuations are critically enhanced upon cooling. Here, we present the characteristics of spin fluctuations over wide doping region of La1111-based compounds, and discuss the relationship with the superconductivity.
Vortex Dynamics and Critical Current Densities in 90 K-phase and 60 K-phase YBa2Cu3O7−δ
with Splayed Columnar Defects
Authors: Wang J , Ito N , Pyon S , Nishizaki T , Tamegai T
Published: August 2022

Enhancement of critical current density (J
c) was observed in YBa2Cu3O7−δ
with splayed columnar defects (CDs). In the case of 90 K-phase YBa2Cu3O7−δ
with splayed CDs, the enhanced J
c drops suddenly at the depinning temperature of vortices from CDs (T
dp), which is interpreted to be caused by the excitation of double kinks traversing neighboring CDs. In addition to the optimal 90 K-phase, where the superconductivity dominates, there is another stable 60 K-phase and other phases with different T
c. This study reports temperature dependence of J
c and the step-like decrease of J
c in YBa2Cu3O7−δ
with CDs and with different T
c. Results show that the T
dp is strongly related to the T
c. However, additional entropic reduction of T
dp may depend on parameters other than T
c.
Study on performance improvement of superconductive-assisted machining (SUAM) with superconducting tape
Authors: Iwasaki S , Kinoshita Y , Ishii H , Otabe E S , Nakasaki T , Suzuki K
Published: August 2022

In this study, we calculated the repulsive force of magnetic levitation for superconductive-assisted machining (SUAM) using the finite element method. Conventionally, SUAM utilizes bulk superconductors; here, we propose a magnetic levitation tool using superconducting tape. To obtain a stronger repulsive force, we fabricated various SUAM models and performed calculations. The results showed that we could obtain a strong repulsive force by arranging six superconducting tape pieces radially at equal intervals from the center of the SUAM tool, shortening the distance between the layers, and making the tape trapezoidal in shape. By increasing the number of layers, we can expect to achieve a greater repulsive force than that obtained with bulk superconductors.
PySQIF, a Statistical Analysis Tool for Bi-SQUID Magnetometers
Authors: Akgun A , Razmkhah S
Published: August 2022

Superconductor loops with Josephson junctions such as SQUIDs and Bi-SQUID have unique properties that can be used as quantum accurate magnetometers, amplifiers, and many more applications. However, due to quantum interference between junctions and their nonlinear nature, their interaction with magnetic fields is hard to analyze. In this work, we introduce an open-source library titled PySQIF that determines the voltage response of the SQUIDs and Bi-SQUIDs in the presence of the external magnetic flux and can determine the design parameter margins by a statistical approach. This library was used to design and fabricate a Bi-SQUID magnetometer.
Narrow-area Bragg-edge transmission of iron samples using superconducting neutron sensor
Authors: Vu The Dang , Shishido Hiroaki , Aizawa Kazuya , Oku Takayuki , Oikawa Kenichi , Harada Masahide , Kojima Kenji M. , Miyajima Shigeyuki , Soyama Kazuhiko , Koyama Tomio , Hidaka Mutsuo , Suzuki Soh Y. , Tanaka Manobu M. , Malins Alex , Machida Masahiko , Ishida Takekazu
Published: August 2022

This study investigates a current-biased kinetic inductance detector (CB-KID) performance by investigating Bragg-edge spectra from the restricted-area neuron transmission of materials. Iron samples with a size of 5 × 5 ×2 mm3 were used as typical test materials. The ergodic theorem was used to obtain a visible transmission spectrum so that a long-time averaging of a transmission spectrum can alternatively be evaluated using a space average of independently selected area spectra with the same ensemble size. The most visible edges were observed with a limited area sample of 0.43 mm2 using a minimum time bin of 25 μs in a time-of-flight (ToF) spectrum or a wavelength resolution of 0.0007 nm of each neutron pulse at beamline BL10 of the Japan Proton Accelerator Research Complex (J-PARC) center. The main Bragg edge of iron as a sum of random 100 ensembles (with an ensemble size of 3.1 × 2.3 μm2) thus obtained has a distinctive signal-to-noise ratio and can be fitted well with the Rietveld Imaging of Transmission Spectra (RITS) program with Miller indices. We consider that our CB-KID system is, in principle, able to analyze the Bragg edge of samples as small as 3.1 × 2.3 μm2.
Braiding Operations for a Topological Josephson Junction Array using SFQ Current Pulses
Authors: Funazawa Takuro , Naruse Masato , Myoren Hiroaki
Published: August 2022

Majorana bound states (MBSs) can occur in topological Josephson junction (JJ) arrays with the presence of a fractional vortex with 2π-phase winding. It has been theoretically shown that the braiding operation can be achieved by using current pulses, compatible with single flux quantum (SFQ) technology. Therefore, we designed an SFQ logic circuit for the braiding operations of the topological JJ array using single flux quanta in a conventional JJ array. Braiding operations could be realized by an SFQ logic circuit with double flux quantum driver. To obtain positive and negative current pulses using the SFQ logic circuit, we used SFQ logic circuits with ac biasing for simulation. Finally, we confirmed the CNOT operation using an array-type SFQ circuit by means of simulation and estimated the CNOT operation speed.
Characterisation of irradiated and non-irradiated silicon sensors with a table-top two photon absorption TCT system
Authors: Pape S. , Fernández García M. , Moll M. , Montero R. , Palomo F.R. , Vila I. , Wiehe M.
Published: August 2022

A tabletop Two Photon Absorption-Transient Current Technique (TPA-TCT) set-up built at CERN was used to investigate a non-irradiated PIN diode, an irradiated PIN diode, and a non-irradiated 5 × 5-multipad HPK LGAD. The intrinsic three dimensional spatial resolution of this method is demonstrated under normal incidence of the laser probe. A charge collection versus depth profile of the non-irradiated PIN diode is presented, where reflection on the rear silicon-air interface was observed. It is found that the time-over-threshold versus depth profile is particularly suitable to determine the boundaries of the DUT’s active volume. A depth scan of the irradiated PIN diode is discussed and a method to omit the single photon absorption background is presented. Finally, a charge collection measurement in the inter-pad region of the 5 × 5-multipad HPK LGAD is presented and it is demonstrated that TPA-TCT can be used to image the implantation and the electric field of segmented silicon devices in a three dimensional manner.
Harmonic forms on asymptotically ADS metrics
Authors: Franchetti Guido , Sánchez Galán Raúl
Published: August 2022

In this paper we study the rotationally invariant harmonic cohomology of a two-parameter family of Einstein metrics g which admits a cohomogeneity one action of SU(2) × U(1) and has AdS asymptotics. Depending on the values of the parameters, g is either of NUT type, if the fixed-point locus of the U(1) action is zero-dimensional, or of bolt type, if it is two-dimensional. We find that if g is of NUT type then the space of SU(2)-invariant harmonic two-forms is three-dimensional and consists entirely of self-dual forms; if g is of bolt type it is four-dimensional. In both cases we explicitly determine a basis. The pair (g, F) for F a self-dual harmonic two-form is also a solution of the bosonic sector of 4D supergravity. We determine for which choices it is a supersymmetric solution and the amount of preserved supersymmetry.
Electronic structure of lattice relaxed alternating twist tNG-multilayer graphene: from few layers to bulk AT-graphite
Authors: Leconte Nicolas , Park Youngju , An Jiaqi , Samudrala Appalakondaiah , Jung Jeil
Published: August 2022

Alternating twist (AT) multilayer graphene systems are at the heart of recent research efforts on flat band superconductivity and therefore precise descriptions of their atomic and electronic structures are desirable. We present the electronic structure of AAʹAAʹ… stacked AT N-layer (tNG) graphene for

N
=

3-10, 20 layers and bulk AT graphite systems where the atomic structure is relaxed using a molecular dynamics simulation code. The low energy bands depend sensitively on the relative sliding between the layers but we show explicitly up to N = 6 that the highly symmetric AA′AA′. . . stacking is energetically preferred among all interlayer sliding geometries of each added layer, justifying why experimental devices consistently show results compatible with this geometry. It is found that lattice relaxation enhances electron–hole asymmetry, and leads to small reductions of the magic angle values with respect to analytical or continuum model calculations with fixed tunneling strengths that we quantify from few layers to bulk AT-graphite. The twist angle error tolerance near the magic angles obtained by maximizing the density of states of the nearly flat bands expand progressively from 0.05∘ for twisted bilayer graphene to up to 0.2∘ for AT-graphite, hence allowing a greater twist angle flexibility in multilayers. We further comment on the role of perpendicular electric and magnetic fields in modifying the electronic structure of the system and how the decoupling of tNG multilayers bands allows mapping onto those of periodic AT-graphite’s at different k

z
values.
Silicene’s pervasive surface alloy on Ag(111): a scaffold for two-dimensional growth
Authors: Küchle Johannes T , Baklanov Aleksandr , Seitsonen Ari P , Ryan Paul T P , Feulner Peter , Pendem Prashanth , Lee Tien-Lin , Muntwiler Matthias , Schwarz Martin , Haag Felix , Barth Johannes V , Auwärter Willi , Duncan David A , Allegretti Francesco
Published: August 2022

Silicene, the two-dimensional (2D) allotrope of silicon, is a promising material for electronics. So far, the most direct synthesis strategy has been to grow it epitaxially on metal surfaces; however, the effect of the strong silicon-metal interaction on the structure and electronic properties of the metal-supported silicene is generally poorly understood. In this work, we consider the

4
×
4

-silicene monolayer (ML) grown on Ag(111), probably the most illustrious representative of the 2D silicon family, and show that our experimental results refute the common interpretation of this system as a simple buckled, honeycomb ML with a sharp interface to the Ag substrate. Instead, the presented analysis demonstrates the pervasive presence of a second silicon species, which we conclude to be a Si–Ag alloy stacked between the 2D silicene and the silver substrate and scaffolding the 2D silicene layer. These findings question the current structural understanding of the silicene/Ag(111) interface and may raise expectations of analogous alloy systems in the stabilization of other 2D materials grown epitaxially on metal surfaces.
Study on the performance of environmental micro-surfacing for exhaust purification
Authors: Li Zhenxia , Guo Tengteng , Chen Yuanzhao , Yang Mingzhu , Wang Ning , Wang Jing , Jin Lihui
Published: August 2022

In order to endow pavement materials with environmental protection properties such as automobile exhaust purification, an environmentally friendly micro-surfacing material with exhaust purification was prepared. Functional materials with photocatalytic activity were prepared by sol-gel method. The best preparation scheme of composite modified asphalt was determined by comparative test. The mix proportion of micro-surfacing mixture was designed to determine the optimal preparation process of micro-surfacing. Based on rutting test, wet wheel wear test and pendulum test, the road performance of protective environmental micro-surfacing with exhaust purification function is studied. An exhaust gas purification test equipment is improved to determine the test method and analyze the exhaust gas purification performance of protective environmental micro-surfacing materials. The results showed that when the molecular weight ratio of Ti : N : Fe was 1 : 0.7 : 0.005, the photocatalytic performance of the prepared environmental functional material with tail gas purification effect was the best. The availability of photocatalytic materials is increased, and the photocatalytic performance is the optimum. When 3% functional materials and 5% SBR latex are used as composite modifier of emulsified asphalt, the consistency, cracking resistance and high temperature performance of composite modified emulsified asphalt are the optimum. The micro-surfacing mixture prepared with 7% oil-stone ratio and 6%–7% external water has good high temperature stability, water stability and skid resistance. When the molecular weight ratio of Ti : N : Fe is 1 : 0.7 : 0.005, the HC purification efficiency reaches 12%, the CO purification efficiency reaches 15%, and the NOX purification efficiency reaches 30%, which has good road performance and exhaust purification effect.
Reflexivity of Newton–Okounkov bodies of partial flag varieties
Authors: Steinert Christian
Published: August 2022

Assume that the valuation semigroup

Γ
(
λ
)

\Gamma (\lambda )

of an arbitrary partial flag variety corresponding to the line bundle

L
λ

\mathcal {L_\lambda }

constructed via a full-rank valuation is finitely generated and saturated. We use Ehrhart theory to prove that the associated Newton–Okounkov body — which happens to be a rational, convex polytope — contains exactly one lattice point in its interior if and only if

L

λ

\mathcal {L}_\lambda

is the anticanonical line bundle. Furthermore, we use this unique lattice point to construct the dual polytope of the Newton–Okounkov body and prove that this dual is a lattice polytope using a result by Hibi. This leads to an unexpected, necessary and sufficient condition for the Newton–Okounkov body to be reflexive.
Computing the exact number of periodic orbits for planar flows
Authors: Graça Daniel , Zhong Ning
Published: August 2022

In this paper, we consider the problem of determining the exact number of periodic orbits for polynomial planar flows. This problem is a variant of Hilbert’s 16th problem. Using a natural definition of computability, we show that the problem is noncomputable on the one hand and, on the other hand, computable uniformly on the set of all structurally stable systems defined on the unit disk. We also prove that there is a family of polynomial planar systems which does not have a computable sharp upper bound on the number of its periodic orbits.
Prioritizing Patient Safety and Minimizing Waste: Institutional Review of Cases and a Proposed Process for Designing a Surgical Pathology Gross-Only Examination Policy
Authors: Harris Cynthia K , Pyden Alexander , Onken Allison M , Yarsky Benjamin , Hayne Cynthia , Glickman Jonathan , Heher Yael K
Published: August 2022

Objectives

Gross-only examination policies vary widely across pathology departments. Several studies—particularly a College of American Pathologists’ Q-Probes study—have looked at the variations in gross-only policies, and even more studies have addressed the (in)appropriateness of certain specimen types for gross-only examination. Few, if any, studies have tackled the important task of how to revise and safely implement a new gross-only examination protocol, especially in collaboration with clinical colleagues.

Methods

We reviewed the grossing protocols from three anatomic pathology centers to identify common gross-only specimen types. We compiled an inclusive list of any specimen types that appeared on one or more centers’ lists. We performed a retrospective review of the gross and microscopic diagnoses for those specimen types to determine if any diagnoses of significance would have been missed had that specimen been processed as a gross-only.

Results

We reviewed 940 cases among 13 specimen types. For 7 specimen types, the gross diagnoses provided equivalent information to the microscopic diagnoses. For 6 specimen types, microscopic diagnoses provided clinically meaningful information beyond what was captured in the gross diagnoses.

Conclusions

To improve the value of care provided, pathology departments should conduct internal reviews and consider transitioning specimen types to gross-only when safe.
Marine Pelagic Ecosystem Responses to Climate Variability and Change
Authors: Ducklow Hugh , Cimino Megan , Dunton Kenneth H , Fraser William R , Hopcroft Russell R , Ji Rubao , Miller Arthur J , Ohman Mark D , Sosik Heidi M
Published: August 2022

abstract

The marine coastal region makes up just 10% of the total area of the global ocean but contributes nearly 20% of its total primary production and over 80% of fisheries landings. Unicellular phytoplankton dominate primary production. Climate variability has had impacts on various marine ecosystems, but most sites are just approaching the age at which ecological responses to longer term, unidirectional climate trends might be distinguished. All five marine pelagic sites in the US Long Term Ecological Research (LTER) network are experiencing warming trends in surface air temperature. The marine physical system is responding at all sites with increasing mixed layer temperatures and decreasing depth and with declining sea ice cover at the two polar sites. Their ecological responses are more varied. Some sites show multiple population or ecosystem changes, whereas, at others, changes have not been detected, either because more time is needed or because they are not being measured.
Atrial tachycardia related to atrial infarction treated with catheter ablation: a case report
Authors: Fujiwara Momo , Yamashita Soichiro , Takemoto Makoto , Hayashi Takatoshi
Published: August 2022

Background

Atrial infarction, usually concurrent with ventricular infarction, is under-recognized. Although most patients with atrial infarction have complicated supraventricular tachyarrhythmias, its mechanism is still unknown. We report a case of atrial tachycardia (AT) related to atrial infarction treated with catheter ablation.

Case summary

A 51-year-old man was referred for acute chest pain. Electrocardiography showed a junctional rhythm with ST depression in the precordial leads. Emergency coronary angiography revealed an occluded dominant left circumflex coronary artery (LCX). A drug-eluting stent was deployed; however, the atrial branch from the distal side of the LCX was jailed by the stent and became occluded. On the 7th day, the premature atrial contractions (PACs) became frequent and changed to AT. Owing to its resistance to medication, we performed catheter ablation. The electro-anatomical map revealed counter-clockwise macro-reentrant tachycardia at the tricuspid valve annulus, with low-voltage and fragmented potential (FP) areas at the posterior wall of the right atrium (RA). After terminating the AT through linear ablation for the cavotricuspid isthmus, multiple-focus PACs originating from the FP area in the RA posterior wall were documented. Coronary angiography revealed that these damaged areas were perfused by the atrial branch of the LCX. Defragmentation in the FP area could eliminate PACs. The patient was discharged with sinus rhythm and without any complications.

Discussion

We can perform electro-anatomical mapping to identify tachycardia circuit and PACs arising from the FP area in the posterior RA, where the atrial branch was perfusing. Multiple PACs from infarcted myocardium result in tachycardia.
A case report of refractory angina in a patient with diabetes and apical hypertrophic cardiomyopathy
Authors: Jex Nicholas , Chowdhary Amrit , Thirunavukarasu Sharmaine , Levelt Eylem
Published: August 2022

Background

Using serial imaging over time, this case reviews the natural history of co-morbid Type two diabetes (T2D) and apical hypertrophic cardiomyopathy (HCM) and assesses the potential combined impact on myocardial structure and perfusion.

Case summary

A 59-year-old patient with concomitant T2D and an apical phenotype of HCM was seen over a 11-year period with a significant burden of anginal chest pain. Chest pain was refractory to anti-anginal medical therapy and persisted at on-going follow-up. Multi-modality imaging demonstrated significant deterioration in coronary microvascular function and increased myocardial scar burden despite unobstructed epicardial coronary arteries.

Discussion

Comorbidity with T2D and apical HCM resulted in a significant increase in myocardial fibrosis and deterioration in coronary microvascular function.
Commentary—fat but fit…and cold? Potential evolutionary and environmental drivers of metabolically healthy obesity
Authors: Ocobock Cara , Niclou Alexandra
Published: August 2022

As global obesity rates continue to rise, it is important to understand the origin, role and range of human variation of body mass index (BMI) in assessing health and healthcare. A growing body of evidence suggests that BMI is a poor indicator of health across populations, and that there may be a metabolically healthy obese phenotype. Here, we review the reasons why BMI is an inadequate tool for assessing cardiometabolic health. We then suggest that cold climate adaptations may also render BMI an uninformative metric. Underlying evolutionary and environmental drivers may allow for heat conserving larger body sizes without necessarily increasing metabolic health risks. However, there may also be a potential mismatch between modern obesogenic environments and adaptations to cold climates, highlighting the need to further investigate the potential for metabolically healthy obese phenotypes among circumpolar and other populations as well as the broader meaning for metabolic health.
Including measures of chronic kidney disease to improve cardiovascular risk prediction by SCORE2 and SCORE2-OP
Authors: Matsushita Kunihiro , Kaptoge Stephen , Hageman Steven H J , Sang Yingying , Ballew Shoshana H , Grams Morgan E , Surapaneni Aditya , Sun Luanluan , Arnlov Johan , Bozic Milica , Brenner Hermann , Brunskill Nigel J , Chang Alex R , Chinnadurai Rajkumar , Cirillo Massimo , Correa Adolfo , Ebert Natalie , Eckardt Kai-Uwe , Gansevoort Ron T , Gutierrez Orlando , Hadaegh Farzad , He Jiang , Hwang Shih-Jen , Jafar Tazeen H , Jassal Simerjot K , Kayama Takamasa , Kovesdy Csaba P , Landman Gijs W , Levey Andrew S , Lloyd-Jones Donald M , Major Rupert W , Miura Katsuyuki , Muntner Paul , Nadkarni Girish N , Nowak Christoph , Ohkubo Takayoshi , Pena Michelle J , Polkinghorne Kevan R , Sairenchi Toshimi , Schaeffner Elke , Schneider Markus P , Shalev Varda , Shlipak Michael G , Solbu Marit D , Stempniewicz Nikita , Tollitt James , Valdivielso José M , van der Leeuw Joep , Wang Angela Yee-Moon , Wen Chi-Pang , Woodward Mark , Yamagishi Kazumasa , Yatsuya Hiroshi , Zhang Luxia , Dorresteijn Jannick A N , Di Angelantonio Emanuele , Visseren Frank L J , Pennells Lisa , Coresh Josef
Published: August 2022

Aims

The 2021 European Society of Cardiology (ESC) guideline on cardiovascular disease (CVD) prevention categorizes moderate and severe chronic kidney disease (CKD) as high and very-high CVD risk status regardless of other factors like age and does not include estimated glomerular filtration rate (eGFR) and albuminuria in its algorithms, systemic coronary risk estimation 2 (SCORE2) and systemic coronary risk estimation 2 in older persons (SCORE2-OP), to predict CVD risk. We developed and validated an ‘Add-on’ to incorporate CKD measures into these algorithms, using a validated approach.

Methods

In 3,054 840 participants from 34 datasets, we developed three Add-ons [eGFR only, eGFR + urinary albumin-to-creatinine ratio (ACR) (the primary Add-on), and eGFR + dipstick proteinuria] for SCORE2 and SCORE2-OP. We validated C-statistics and net reclassification improvement (NRI), accounting for competing risk of non-CVD death, in 5,997 719 participants from 34 different datasets.

Results

In the target population of SCORE2 and SCORE2-OP without diabetes, the CKD Add-on (eGFR only) and CKD Add-on (eGFR + ACR) improved C-statistic by 0.006 (95%CI 0.004–0.008) and 0.016 (0.010–0.023), respectively, for SCORE2 and 0.012 (0.009–0.015) and 0.024 (0.014–0.035), respectively, for SCORE2-OP. Similar results were seen when we included individuals with diabetes and tested the CKD Add-on (eGFR + dipstick). In 57 485 European participants with CKD, SCORE2 or SCORE2-OP with a CKD Add-on showed a significant NRI [e.g. 0.100 (0.062–0.138) for SCORE2] compared to the qualitative approach in the ESC guideline.

Conclusion

Our Add-ons with CKD measures improved CVD risk prediction beyond SCORE2 and SCORE2-OP. This approach will help clinicians and patients with CKD refine risk prediction and further personalize preventive therapies for CVD.
I Am Not Supposed to Be Treated Like This: Associations Between Age Discrimination, Perceived Social Respect for Older Adults, and Depressive Symptoms in Korean Older Adults
Authors: Lee Min-Ah , Song Rira
Published: August 2022

Objectives

This study examines the relationships between age discrimination, perceived social respect for older adults as a proxy of perceived social climate, and depressive symptoms in older adults in Korea. In doing so, it clarifies whether and how age discrimination has a differential effect on mental health, depending on the level of perceived social respect.

Methods

This study uses multiple regression analyses to examine the data obtained from the 2020 National Survey of Older Koreans, a nationally representative survey.

Results

Findings show that age discrimination was positively associated with depressive symptoms, whereas perceived social respect for older adults was negatively associated with depressive symptoms. Older respondents exhibited fewer depressive symptoms if they felt that older adults were respected in Korea. The results also revealed a significant interaction between age discrimination and perceived social respect; age discrimination had a more harmful impact on depressive symptoms in older adults with a higher level of perceived social respect.

Discussion

The findings suggest that a positive social climate for older adults is beneficial to their mental health, but ironically, it may form a more stressful context for older adults who experience age discrimination that is characteristically opposite from their subjective evaluation of that social climate. The gap between the expected social climate and individual discriminatory experiences may have a deleterious effect on the mental health of older adults.
Intent-Based Moral Judgment in Old Age
Authors: Margoni Francesco , Cho Isu , Gutchess Angela
Published: August 2022

Objectives

Recent studies support the idea of an intent-to-outcome shift in moral judgments with age. We further assessed whether a reduced reliance on intentions is associated with aging in a preregistered study with 73 younger (20–41 years) and 79 older (70–84 years) adults, group-matched on education level.

Method

Participants were presented with a set of moral cases to evaluate, created by varying orthogonally the valence (neutral, negative) of the information regarding the agent’s intentions and the action’s outcomes.

Results

The two age groups did not differ in the extent they relied on intentions in moral judgment.

Discussion

These results suggest that an intent-to-outcome shift might not be found in all aging populations, challenging prevailing theories suggesting that aging is necessarily associated with a reduced reliance on intentions.
Characterization of the Complete Chloroplast Genome of Four Species in Callerya
Authors: Chen Zhi , Jin Chen , Wang Xiaoyun , Deng Yaqiong , Tian Xiaodan , Li Xunxun , Zhang Qinxi , Zeng Yanli , Liao Jiawei , Zhang Ling
Published: August 2022

Background

Callerya reticulata (Bentham) Schot, Callerya dielsiana (Harms) P.K. Loc ex Z. Wei & Pedley, Callerya nitida var. hirsutissima (Z. Wei) X.Y. Zhu, and Callerya nitida (Bentham) R. Geesink, which belongs to the Leguminosae family, are important medicinal plants in China. The genus Callerya includes 26 species, 18 species are distributed in China, and the vine stems of some species are used as traditional medicinal herbs because they have important pharmacological activity. Due to the high similarity of appearance, it is difficult to identify them in the market by appearance alone. Therefore, circulating of Callerya-related materia medica on the market is confusing, sometimes even leading to drug safety problems. It is urgent to develop molecular methods for their identification.

Objective

To sequence and analyze the complete chloroplast (cp) genomes of C. reticulata, C. dielsiana, C. nitida var. hirsutissima, and C. nitida and to analyze their cp genome differences as a basis for seeking easier DNA barcoding for their identification.

Method

After using Illumina high-throughput sequencing and nanopore sequencing to obtain the genome data, some bioinformatics software was used to assembly and analyze the molecular structure of cp genomes.

Results

The complete cp genomes of the four species were circular molecules, which ranged from 130 435 to 132 546 bp, and GC contents ranged from 33.89% to 34.89%. Each of them includes a large single-copy region, a small single-copy region, and without large inverted repeat regions.

Conclusions

These results suggested that highly variable regions of the four cp genomes would provide useful plastid markers, which could be used as a potential genomic resource to resolve phylogenetic questions and provide a reference for mining specific DNA barcodes of these species.

Highlights

Our study provided highly effective molecular markers for subsequent phylogenetic analysis, species identification, and biogeographic analysis of Callerya.
Temporal Changes in Cholangiocarcinoma Incidence and Mortality in the United States from 2001 to 2017
Authors: Javle Milind , Lee Sunyoung , Azad Nilofer S , Borad Mitesh J , Kate Kelley Robin , Sivaraman Smitha , Teschemaker Anna , Chopra Ishveen , Janjan Nora , Parasuraman Shreekant , Bekaii-Saab Tanios S
Published: August 2022

Background

Previous studies report increasing cholangiocarcinoma (CCA) incidence up to 2015. This contemporary retrospective analysis of CCA incidence and mortality in the US from 2001-2017 assessed whether CCA incidence continued to increase beyond 2015.

Patients and Methods

Patients (≥18 years) with CCA were identified in the National Cancer Institute Surveillance, Epidemiology, and End Results 18 cancer registry (International Classification of Disease for Oncology [ICD-O]-3 codes: intrahepatic [iCCA], C221; extrahepatic [eCCA], C240, C241, C249). Cancer of unknown primary (CUP) cases were identified (ICD-O-3: C809; 8140/2, 8140/3, 8141/3, 8143/3, 8147/3) because of potential misclassification as iCCA.

Results

Forty-thousand-and-thirty CCA cases (iCCA, n=13,174; eCCA, n=26,821; iCCA and eCCA, n=35) and 32,980 CUP cases were analyzed. From 2001-2017, CCA, iCCA, and eCCA incidence (per 100 000 person-years) increased 43.8% (3.08 to 4.43), 148.8% (0.80 to 1.99), and 7.5% (2.28 to 2.45), respectively. In contrast, CUP incidence decreased 54.4% (4.65 to 2.12). CCA incidence increased with age, with greatest increase among younger patients (18-44 years, 81.0%). Median overall survival from diagnosis was 8, 6, 9, and 2 months for CCA, iCCA, eCCA, and CUP. From 2001-2016, annual mortality rate declined for iCCA (57.1% to 41.2%) and generally remained stable for eCCA (40.9% to 37.0%) and for CUP (64.3% to 68.6%).

Conclusions

CCA incidence continued to increase from 2001-2017, with greater increase in iCCA versus eCCA, whereas CUP incidence decreased. The divergent CUP versus iCCA incidence trends, with overall greater absolute change in iCCA incidence, provide evidence for a true increase in iCCA incidence that may not be wholly attributable to CUP reclassification.
Circulating Concentrations of Nutrition-Related Factors Are Not Causally Associated With Atrial Fibrillation: A Mendelian Randomization Study
Authors: Huang Jian
Published: August 2022

Observational studies reported conflicting results regarding the association between circulating concentrations of nutrition-related factors and atrial fibrillation (AF). The aim of this study was to evaluate the potential causal effect of 8 circulating nutrition-related factors (vitamin B12, vitamin E, folate, retinol, β-carotene, iron, zinc, and copper) on AF risk using mendelian randomization (MR). Summary-level data for the nutrition-related factors and AF were obtained from genome-wide association studies conducted among individuals of European ancestry. The genome-wide association study on AF included 60,620 cases and 970,216 controls. A 2-sample MR design was applied for evaluating the causal association. In the primary MR analyses, the inverse variance–weighted method did not identify any causal effect of circulating concentrations of vitamin B12 [β = 0.000, standard error (SE) = 0.021, P = 0.994], vitamin E (β = 0.080, SE = 0.152, P = 0.600), retinol (β = 0.098, SE = 0.397, P = 0.806), folate (β = −0.006, SE = 0.052, P = 0.901), β-carotene (β = 0.014, SE = 0.025, P = 0.560), iron (β = −0.009, SE = 0.072, P = 0.905), zinc (β = 0.038, SE = 0.032, P = 0.239), and copper (β = −0.012, SE = 0.023, P = 0.589) on AF. The MR-Egger and MR pleiotropy residual sum and outlier (MR-PRESSO) analyses did not suggest the presence of pleiotropy. In addition, the lack of association remained in the leave-one-out analysis. This MR study indicates no causal association of circulating concentrations of vitamin B12, vitamin E, folate, retinol, β-carotene, iron, zinc, and copper with AF.
Efficacy and Safety of De-escalation of Antiplatelet Therapy After Percutaneous Coronary Intervention in Patients With Acute Coronary Syndrome: A Meta-Analysis of Randomized Clinical Trials
Authors: Bai Nan , Ma Ying , Niu Ying , Zhong Peng-Yu , Shang Yao-Sheng , Wang Zhi-Lu
Published: August 2022

Considering that there is no definite conclusion on the efficacy and safety of switching from potent P2Y12 inhibitors to clopidogrel, we conducted a systematic review and meta-analysis of patients with acute coronary syndromes undergoing percutaneous coronary intervention and compared the efficacy and safety of de-escalation or not of antiplatelet therapy. The relevant randomized controlled trials were included by searching several databases. Net adverse clinical events were identified as the composite end point, which was defined as a composite of cardiovascular death, myocardial infarction, revascularization, stroke, and bleeding at 12 months after acute coronary syndromes. The efficacy end points were cardiovascular death, myocardial infarction, revascularization, stroke, all-cause death, and stent thrombosis. Bleeding was designed as the safety end point. The risk ratio and 95% confidence intervals of end point events were calculated by the fixed-effects model. Six randomized controlled trials with 7627 patients met inclusion criteria. There were significant differences in the risk of net adverse clinical events (RR, 0.67, CI, 0.58–0.78, P < 0.00001) and bleeding end point (0.61, 0.52–0.71, P < 0.00001) between the 2 groups. However, there were no significant differences in the risk of all efficacy end points. In general, the strategy of de-escalation from prasugrel or ticagrelor to clopidogrel can reduce the incidence of net adverse clinical events and bleeding events in patients with ACS undergoing percutaneous coronary intervention.
Hypersensitivity of Zebrafish htr2b Mutant Embryos to Sertraline Indicates a Role for Serotonin Signaling in Cardiac Development
Authors: Kent Mitchell E. , Hu Bo , Eggleston Timothy M. , Squires Ryan S. , Zimmerman Kathy A. , Weiss Robert M. , Roghair Robert D. , Lin Fang , Cornell Robert A. , Haskell Sarah E.
Published: August 2022

Selective serotonin reuptake inhibitors (SSRIs) are antidepressants prescribed in 10% of pregnancies in the United States. Maternal use of SSRIs has been linked to an elevated rate of congenital heart defects, but the exact mechanism of pathogenesis is unknown. Previously, we have shown a decrease in cardiomyocyte proliferation, left ventricle size, and reduced cardiac expression of the serotonin receptor 5-HT2B in offspring of mice exposed to the SSRI sertraline during pregnancy, relative to offspring of untreated mice. These results suggest that disruption of serotonin signaling leads to heart defects. Supporting this conclusion, we show here that zebrafish embryos exposed to sertraline develop with a smaller ventricle, reduced cardiomyocyte number, and lower cardiac expression of htr2b relative to untreated embryos. Moreover, zebrafish embryos homozygous for a nonsense mutation of htr2b (htr2b

sa16649
) were sensitized to sertraline treatment relative to wild-type embryos. Specifically, the ventricle area was reduced in the homozygous htr2b mutants treated with sertraline compared with wild-type embryos treated with sertraline and homozygous htr2b mutants treated with vehicle control. Whereas long-term effects on left ventricle shortening fraction and stroke volume were observed by echocardiography in adult mice exposed to sertraline in utero, echocardiograms of adult zebrafish exposed to sertraline as embryos were normal. These results implicate the 5-HT2B receptor functions in heart development and suggest zebrafish are a relevant animal model that can be used to investigate the connection between maternal SSRI use and elevated risk of congenital heart defects.