bluuebunny/crossref_metadata_2025 huggingface dataset:
Topological spin crystals by itinerant frustration
Authors: Hayami Satoru , Motome Yukitoshi
Published: August 2021

Spin textures with nontrivial topology, such as vortices and skyrmions, have attracted attention as a source of unconventional magnetic, transport, and optical phenomena. Recently, a new generation of topological spin textures has been extensively studied in itinerant magnets; in contrast to the conventional ones induced, e.g., by the Dzyaloshinskii–Moriya interaction in noncentrosymmetric systems, they are characterized by extremely short magnetic periods and stable even in centrosymmetric systems. Here we review such new types of topological spin textures with particular emphasis on their stabilization mechanism. Focusing on the interplay between charge and spin degrees of freedom in itinerant electron systems, we show that itinerant frustration, which is the competition among electron-mediated interactions, plays a central role in stabilizing a variety of topological spin crystals including a skyrmion crystal with unconventional high skyrmion number, meron crystals, and hedgehog crystals. We also show that the essential ingredients in the itinerant frustration are represented by bilinear and biquadratic spin interactions in momentum space. This perspective not only provides a unified understanding of the unconventional topological spin crystals but also stimulates further exploration of exotic topological phenomena in itinerant magnets.
Poly(m-phenylenediamine) encapsulated graphene for enhancing corrosion protection performance of epoxy coatings
Authors: Zhang Jie , Zheng Yuying
Published: August 2021

Graphene (G) is regarded as a tremendous potential corrosion protection material owing to its perfect impermeability. However, the tendency of graphene nanosheets to agglomerate and the corrosion-promotion effect brought by its native high electrical conductivity seriously affect its anti-corrosion application. In this paper, high-energy ball milling was used to prepare graphene with excellent impermeability. Then, insulating poly(m-phenylenediamine) encapsulated graphene (G@PmPD, conductivity of 1.2 × 10−7 S cm−1) was prepared through non-covalent π–π interaction. The resulting amino-rich G@PmPD exhibits stable dispersibility and excellent compatibility in organic solvents and polymer matrix. Embedding 0.5 wt% of G@PmPD into the epoxy matrix, and the composite coating can effectively protect the steel substrate for up to 60 d. This superior corrosion resistance is attributed to the impermeability inherited by G@PmPD and the compactness improved by the cross-linking of G@PmPD and EP. Especially in the damaged state, the composite coating embedded with low conductivity G@PmPD triumphantly eliminated graphene’s corrosion-promotion effect. This study provides promising inspiration for the application of graphene in anti-corrosion field.
On real and pseudo-real rational maps
*
Authors: Hidalgo Ruben A , Quispe Saúl
Published: August 2021

The moduli space M
d
, of complex rational maps of degree d ⩾ 2, is a connected complex orbifold which carries a natural real structure, coming from usual complex conjugation. Its real points are the classes of rational maps admitting antiholomorphic automorphisms. The locus of the real points

M

d

(

R

)

decomposes as a disjoint union of the loci

M

d

R

, consisting of the real rational maps, and

P

d

, consisting of the pseudo-real ones. We obtain that, both

M

d

R

and

M

d

(

R

)

, are connected and that

P

d

is disconnected. We also observe that the group of holomorphic automorphisms of a pseudo-real rational map is either trivial or a cyclic group. For every n ⩾ 1, we construct pseudo-real rational maps whose group of holomorphic automorphisms is cyclic of order n. As the field of moduli of a pseudo-real rational map is contained in

R

, these maps provide examples of rational maps which are not definable over their field of moduli. It seems that these are the only explicit examples in the literature (Silverman) of rational maps which cannot be defined over their field of moduli. We provide explicit examples of real rational maps which cannot be defined over their field of moduli. Finally, we also observe that every real rational map, which admits a model over the algebraic numbers, can be defined over the real algebraic numbers.
Analysis of a model of self-propelled agents interacting through pheromone
Authors: Amorim Paulo , Goudon Thierry
Published: August 2021

We establish well-posedness for a model of self-propelled agents interacting through pheromone which they themselves produce. The model consists of an arbitrary number of agents modeled by a system of ordinary differential equations, for which the acceleration term includes the influence of a chemical signal, or pheromone, which induces a turning-like behaviour. The signal is produced by the agents themselves and obeys a diffusion equation. We prove that the resulting system, which is non-local in both time and space, enjoys well-posedness properties, using a fixed point method, and show some numerical results.
Infinitely many localized semiclassical states for critical nonlinear Dirac equations
Authors: Chen Shaowei , Gou Tianxiang
Published: August 2021

In this paper, we are concerned with semiclassical states to the nonlinear Dirac equation with Sobolev critical exponent

−
i
ϵ
α
⋅
∇
u
+
a
β
u
+
V

(

x

)

u
=
|
u

|

q
−
2

u
+
|
u
|
u

in

R

3

, where

u
:

R

3

→

C

4

, 2 < q < 3, ϵ > 0 is a small parameter, a > 0 is a constant, α = (α
1, α
2, α
3), α

j
and β are 4 × 4 Pauli-Dirac matrices. We construct an infinite sequence of semiclassical states with higher energies concentrating around the local minimum points of the potential V. The problem is strongly indefinite and the solutions correspond to critical points of the underlying energy functional at energy levels where compactness condition breaks down. The proof relies on truncation techniques, blow-up arguments together with a local type Pohozaev identity.
Incompressible limit on thin domains with periodic boundary condition
Authors: Li Sai , Li Yang
Published: August 2021

We consider convergence to the incompressible Navier–Stokes equations/Euler equations for compressible viscous flows on periodic thin domain

Ω

δ

=

T

a

2

×
δ
T

with general initial data. Compared with Caggio et al (2020 Nonlinearity
33 840–863), where similar problems are considered in the whole space, we have to deal with the persistence of acoustic waves. We prove that the weak solutions in the 3D domain converge weakly/strongly to the solutions of the 2D incompressible Navier–Stokes equations/Euler equations when the Mach number ɛ goes to 0 as well as the thickness δ/the viscosity goes to 0.
L

q
-spectra of self-affine measures: closed forms, counterexamples, and split binomial sums
Authors: Fraser Jonathan M , Lee Lawrence D , Morris Ian D , Yu Han
Published: August 2021

We study L

q
-spectra of planar self-affine measures generated by diagonal matrices. We introduce a new technique for constructing and understanding examples based on combinatorial estimates for the exponential growth of certain split binomial sums. Using this approach we disprove a theorem of Falconer and Miao from 2007 and a conjecture of Miao from 2008 concerning a closed form expression for the generalised dimensions of generic self-affine measures. We also answer a question of Fraser from 2016 in the negative by proving that a certain natural closed form expression does not generally give the L

q
-spectrum. As a further application we provide examples of self-affine measures whose L

q
-spectra exhibit new types of phase transitions. Finally, we provide new non-trivial closed form bounds for the L

q
-spectra, which in certain cases yield sharp results.
On the non-integrability and dynamics of discrete models of threads
Authors: Kozlov Valery , Polekhin Ivan
Published: August 2021

In the paper, we study the dynamics of planar n-gons, which can be considered as discrete models of threads. The main result of the paper is that, under some weak assumptions, these systems are not integrable in the sense of Liouville. This holds for both completely free threads and for threads with fixed points that are placed in external force fields. We present sufficient conditions for the positivity of topological entropy in such systems. We briefly consider other dynamical properties of discrete threads and we also consider discrete models of inextensible yet compressible threads.
Thermodynamics education for energy transformation: a Stirling Engine experiment
Authors: Yeadon Will , Quinn Mark
Published: August 2021

We present a thermodynamics experiment suitable for first year undergraduate students employing Stirling Engines to create a demonstration of energy transformation and to measure the mechanical efficiency of such engines. Using an inexpensive transparent chambered Stirling Engine, students can connect concepts such as the theoretical pressure-volume diagram with the physical movements of the engine’s pistons and the resultant useful output work of a spinning wheel. We found the majority of students successfully complete this experiment obtaining results similar to when performed by the authors. In addition to the core thermodynamics lesson, this experiment incorporates DC circuits, oscilloscopes, and data analysis so it can be integrated into a wider undergraduate physics course to combine the teaching of multiple subjects.
COVID-19 precautions for public astronomy education sessions
Authors: Carlin Andrew P , Marques Joana B V , Moutinho Ricardo
Published: August 2021

This paper suggests possible futures for astronomy activities in a post-COVID environment. A corpus of video recordings of astronomy education sessions held in different settings allowed the authors to analyse how sessions are achieved, with inclusive focus on the astronomers, the public attending sessions, and people looking through telescopes. Videos were recorded in Portugal in 2019 and the beginning of 2020. From these video data, and experience as science educators, the authors identify practices that are characteristic of astronomy education—some of these will no longer be safe procedures while living with COVID-19. With planning, both indoor and outdoor astronomy education sessions can continue safely without sacrificing the excitement of seeing objects in the sky. There is more to astronomy than looking through a telescope.
Local increase in compressive strain (GaN) in gate recessed AlGaN/GaN MISHFET structures induced by an amorphous AlN dielectric layer
Authors: Mikulics M , Kordoš P , Gregušová D , Gaži Š , Novák J , Sofer Z , Mayer J , Hardtdegen H
Published: August 2021

We fabricated and characterized metal insulator semiconductor (MIS) structures by applying amorphous AlN thin layers as a dielectric in gate recessed AlGaN/GaN heterostructure field effect transistors (HFETs). Micro photoluminescence measurements performed on MISHFET devices reveal a local non-uniform distribution of strain in the source—gate recess—drain region. Furthermore, a reduction of compressive stress up to 0.3 GPa in GaN after gate recessing was experimentally determined. The local stress increases by ∼0.1 GPa and ∼0.2 GPa after the deposition of 4 and 6 nm thin AlN layers in the gate recessed structures, respectively. Additionally, an increase in sheet charge density in the devices under investigation from ∼

3.8
×

10

12

c

m

−
2

 

to ∼

6.2
×

10

12

c

m

−
2

 

was evaluated by capacitance–voltage measurements. Therefore, strain engineering by applying amorphous AlN layers in gate recessed MISHFETs can significantly improve their device characteristics.
High-performance ECRH at W7-X: experience and perspectives
Authors: Laqua H.P. , Baldzuhn J. , Braune H. , Bozhenkov S. , Brunner K. , Hirsch M. , Hoefel U. , Knauer J. , Langenberg A. , Marsen S. , Moseev D. , Pasch E. , Rahbarnia K. , Stange T. , Wolf R.C. , Pablant N. , Grulke O. , the W7-X Team
Published: August 2021

The second operation phase of W7-X (OP1.2) showed the potential of exclusively electron cyclotron resonance heating (ECRH)-sustained plasma operations in stellarators. Employing multi-pass ECRH scenario in the second harmonic O-mode (O2-ECRH), stationary densities of up to 1.4 × 1020 m−3 could be achieved. This scenario also made stationary divertor detachment possible, which is a reactor-relevant scenario for power and particle exhaust. At high densities and with sufficiently high density gradients for an improved ion confinement, the coupling between the electrons and ions was strong enough to bring the ion temperature to values above 3 keV and to the neoclassical limit for some magnetic configurations, thus enabling to test the W7-X neoclassical optimization. The planned enhancement of the ECRH performance will enable to advance towards reactor-relevant beta values and to investigate their stability and confinement of fast particles, which is a priority goal of W7-X.
Comparison between seismic performance of G+5 building with and without Fluid Viscous Dampers
Authors: Tamang Pranita , Prasad Sharma Guru
Published: August 2021

Earthquake causes numerous loss of lives and damage to property. On 18 September 2011, Sikkim also experienced a major earthquake of magnitude 6.9 resulting in large-scale destruction. Therefore, as an attempt to prevent such scenarios, there are various techniques available to manage this problem one of which is by using dampers on building structures. The main objective of this study is to compare the seismic performance of G+5 building with and without dampers. The modelling and analysis in this study are done using “ETABs” software for G+5 story building as the maximum no. of floors allowed in Sikkim is six. The proposed model showed a drastic reduction in the displacement of the building using FVDs.
Challenges faced by Construction Organizations during Covid-19 Era
Authors: Nair Gayathri , Suresh M.
Published: August 2021

The construction industries have been severely affected by the global pandemic Covid 19. The purpose of this paper is to identify and categorize the challenging factors faced by construction organizations during Covid 19 era and to explore the interrelationship among the factors using Total Interpretive Structural Modelling (TISM) approach. The results of the study depict shortage of labour, cautious buyers, material delay, uncertainty of demands and underutilization of renewable resources are independent factors that that are a major challenge for construction organizations. Furthermore, this is the first attempt to understand the challenging factors in construction organizations using the theory building approach like TISM.
Synergic effect of cathodic protection and mineral admixture on the corrosion resistance of reinforcements in concrete
Authors: Iyer Murthy Yogesh , Gandhi Sumit
Published: August 2021

The use of agricultural wastes rich in pozzolanic materials such as Fe2O3, SiO2 and Al2O3 is an active area of research in concrete technology. This improves the mechanical and durability properties along with sustainability. One such waste is the Sugar Cane Bagasse Ash (SCBA) generated by sugar mills and usually dumped in open space. The main purpose of the study is to investigate synergic effect of cathodic protection and using SCBA blended cement concrete on the corrosion resistance of embedded reinforcement and compare it with control concrete. The approach involved construction of eight slabs (1 m X 0.1 m X 0.1 m) and monitoring the half cell potential (HCP) for 270 days. In order to simulate the marine atmosphere, two slabs were constructed with 3.5% NaCl by weight of cement and two others were reference slabs. The pure Magnesium anodes 22 mm diameter and 250 mm long were used. The experimental results indicated that the corrosion of embedded reinforcement in slab containing SCBA was more as compared to slab containing both SCBA and anode.
Numerical Analysis on Different Void Former On ANSYS
Authors: Jain Nikita , Hussain Asif
Published: August 2021

The use of construction materials has risen as culture and technology have grown. Concrete is the most often used of all the essential construction materials. To meet structural specifications, traditional architecture approaches include participants with large sizes. These massive structural elements including columns, slabs, beams, footings, partitions, and so on These massive structural structures have an effect on the volume of concrete used in building around the world. This, in particular, warns us to limit our use of concrete as a building medium because concrete not only adds to the dead load of a house but also produces carbon dioxide as a byproduct, making it detrimental to our climate. This research uses a bi-axial voided slab with various void formers, such as cylindrical, spherical, rectangular, trapezium, and square, spaced at 10mm centre to centre. It removes the concrete from the centre of the slab, resulting in a self-weight reduction of around 6% to 10%. A two bi-axial voided slab functions similarly to a standard slab. The final results met the requirements for strength and serviceability.
Evaluation of User experience for Physical infrastructure in Relocation Project Under BSUP Scheme in Lucknow City
Authors: Prasad Raunak
Published: August 2021

Introduction of various schemes and programmes, over past two decades highlights the thrust of government for provision of affordable housing in India. These schemes were introduced to cater the housing demand and improve basic services, provide tenure security, upgrade existing infrastructure, and create new housing units with a vision of creating a ‘Slum Free India’. It was initiated by introducing the Indra Awas Yojana in 1990 which was applicable to rural India, later by introduction of Jawaharlal Nehru National Urban Renewal Mission (JNNURM) in the year 2005, the focus shifted to urban areas.

JNNURM was carried out under two sub-heads Basic Service to Urban Poor (BSUP) and Integrated Housing and Slum Development Programme (IHSDP) for provision of 1.5 million houses for urban poor in 63 selected cities during 2005-2012. Lucknow city, selected as one of the mission cities was benefitted under the programme through the execution of 7 projects in 23 different areas, providing 5570 housing units along with basic services. The projects include three types of development-in-situ, relocation, and in-situ redevelopment. The paper investigates the status of physical infrastructure – water supply, sanitation, solid waste management and electricity along with the satisfaction level of beneficiaries in relocation projects. The study is carried out using an observation tool and structured interview questionnaire with beneficiaries. The findings of the paper highlight the issues related to maintenance and operation of these services and focuses on need for inclusive development in these projects.
LIME CALCINED CLAY CEMENT (LC3): A Review
Authors: Sahith Reddy S. , Achyutha Kumar Reddy M.
Published: August 2021

Discovery of alternative to the pozzolanic materials generated from industrial wastes was needed because of its unavailability when the industries was shutdown permanently. Consumption of pozzolanic materials in concrete will be a safer solution for this problem. Numerous studies were presented for utilization of fly ash, Ground Granular Blast Furnace Slag (GGBS), Metakaolin and silica fume as a pozzolanic material in concrete. LC3 is a type of cement by mixing of limestone, calcined clay and gypsum, a few literatures were available on LC3. This paper presents the overview of research work presented on physical, chemical, performance in cement mortars like consistency, setting times & compressive strength, properties of fresh & hardened concrete like workability, compressive strength, split tensile strength, flexure strength made LC3.
Assessment of Characterization Procedures for the Implementation of Anaerobic Digestion Model No.1
Authors: Mathur Rajshree , Kumari Sharma Meena
Published: August 2021

In this paper, comparison were made among the characterization processes, designed for influent characterization in Anaerobic Digestion Model No.1 (ADM1) to choose one of the best available. The two procedures chosen are elemental analysis and conversion of Activated sludge Model (ASM) output to ADM1 input variables (ASM2ADM interface) given by John B. Copp, 2003. The Matlab code for elemental analysis was developed to facilitate computation and a c-file of the ASM2ADM interface was provided by the department of Industrial Electrical Engineering and Automation, Lund University Sweden. Both of these methods have been used in the collection of wastewater data from various locations and the demand for chemical oxygen (COD) after separation compared to experimental results. In almost all cases total fractionated COD from ASM2ADM interface was approximately equal to experimental COD. While as fractionation by elemental analysis shows variation from experimental value. Linear curve fitting was done between experimental COD and fractionated COD to check their equivalency. The elemental analysis method has lower value of coefficient of determination (R2 = 0.5468) than ASM2ADM interface (R2 = 0.9453). Based on the model requirements, it was concluded that ASM2ADM interface is the best option for influent characterization. Apart from obtaining good correlation with experimental COD, it provides all input variables for implementation of ADM1. While elemental analysis provide fewer fractionation and hence assumption of other input variables is must leading to deviation from actual model features. Features of both methods are also discussed in the paper.
Physical and Geotechnical Perspectives of Gypsum on Lime Stabilized Expansive Soil: A Critical Appraisal
Authors: Shivanshi  , Kumar Jha Arvind , Akhtar Md. Parwez
Published: August 2021

The gypsum is the source of sulphate commonly found in the soils throughout the world. The expansive soils are considered as problematic soils as they exhibit uncertain swelling and shrinkage in presence of moisture. The expansive soils are treated with different stabilizers to suppress the swelling behaviour. Lime is most effective stabilizer used to stabilize the expansive soil. Researchers reported that expansive soil when treated with lime encounters the gypsum it regenerates the swelling. This regenerated expansion of lime treated soil in presence of sulphate may have alarming signs for sulphate bearing soils. The presence of sulphate alters the mineralogical behaviour of expansive clay. The stabilization additive used f or such soils needs more attention. A comprehensive approach towards proper understanding of the effects of gypsum on lime stabilized soil is required in order to understand the future threats of expansive soils. In this paper, an attempt has been made to present a comprehensive review on the effects of (Gypsum) calcium sulphate dihydrate on the physical properties of untreated and lime treated expansive soil have.
Experimental studies on durability properties of Sustainable and Eco-friendly materials of GGBS and Fly ash in reinforced cement concrete
Authors: Venkata Sekhar Babu Velpuri , Bramha Chari Kanneganti Jyothishya , Vinod Y
Published: August 2021

This paper represents the use of supplementary cementitious material (SCM) with the blend of Portland cement in producing the corrosion resistive concrete. Fly ash and GGBS are partially replaced in three different ratios by the weight of cement. Compressive strength, chloride penetration, corrosion, sorptivity of (FA-GGBS) were determined. The test revealed the confrontation by chloride ions through the infiltration of concrete improves substantially by replacement coal by-product Fly ash, GGBS, and improvement increase with increases in the replacement level. The corrosion resistance of SCM-Proportional Mixes was better than the Control mix concrete. Besides, test results indicated that reduction of permeability of chlorides ion as a reduction in porosity in the concrete, that associates with increases in the compressive strength. It significantly affects the durability of the Supplementary Cementitious Materials. On the same proportional mixes, we have gone with microstructural analysis of Scanning Electron Microscopy (SEM) and (EDX), X-Ray Diffraction and non-Destructive tests are following method. The work is suggested that the higher replacement of cement with SCM shows more satisfactory results in the durability properties of proportional grades of SCM.
Finite Element Analysis of Fatigue and Fracture Behavior in Idealized Airplane Wing Model with Embedded Crack Under Wind Load
Authors: Pandey Harsha , Fernandes Dazan , Khandelwal Arpit , Mishra Dhaneshwar
Published: August 2021

Aircraft wings undergo forces like thrust, drag as well as transient loads due to gust. Even though these loads overall help in the stability of an aircraft but over time it can cause growth of defects such as micro cracks or voids due to fatigue. We would like to investigate the fatigue, fracture failure due to wind load during its long operating life of the airplane. Therefore, we have modeled the airplane wing as cantilever beam and applied fluctuating wind load. The airplane wing with embedded crack was modeled in commercial finite element analysis tool, ANSYS. The drag and lift forces acting as pressure on the adjacent faces of the wing with a transient wind load has been simulated to determine the loads on an aero foil working under similar conditions through CFD analysis. The load estimated through the CFD analysis was applied on the wing model to obtain the stress intensity factor and energy release rate. Analysis for fatigue failure was also carried out to predict life of the idealized model under considered loading. The results obtained through this work can be helpful in understanding the fatigue behavior in the transient loading condition such as wind in airplane wing.
Wise Green Travel: A Local Wisdom Characterized Travel Experience
Authors: Zhang Yan , Sun Minghao
Published: August 2021

The increasing concern on environmental issues has led to the emergence of a new style of travel. In line with this, the study proposes a new kind of travel: wise green travel. This concept of “wise green travel” transcends the general existing notion of reducing environmental pollution. It extends to the wise use of local resources and encouraged interaction/participation in local activities. This paper analyzes the travel distribution in different periods by comparing the thermodynamic diagram which has characteristics of describing the population distribution, population density and the changing trend in real time. Furthermore, the study explores methods that have introduced and announced by famous organizations on how to achieve wise green travel, and a framework illustrating the wise green travel route especially when it is incorporated with local resources. Thus, aside environmental protection, wise green travel also helps local enterprises and the government build a green system for improving self-development and exploration journey of local tourism resources with wisdom.
Creation and validation of a polysocial score for mortality among community-dwelling older adults in the USA: the health and retirement study
Authors: Ping Yongjing , Oddén Michelle C , Stawski Robert S , Abdel Magid Hoda S , Wu Chenkai
Published: August 2021

Background

the interrelatedness between social determinants of health impedes researchers to identify important social factors for health investment. A new approach is needed to quantify the aggregate effect of social factors and develop person- centred social interventions.

Methods

participants ([n = 7,383], 54.5% female) were aged 65 years or above who complete an additional psychosocial questionnaire in the health and retirement study in 2006 or 2008. Social determinants of health encompassed five social domains: economic stability, neighbourhood and physical environment, education, community and social context, and healthcare system. We used the forward stepwise logistic regression to derive a polysocial score model for 5-year mortality. Indices of goodness-of-fit, discrimination and reclassification were used to assess model performance. We used logistic regression to identify the association between polysocial score and mortality. Subgroup analyses were conducted to examine sex- and race-specific association.

Results

polysocial score was created using 14 social determinants of health. In the training cohort, the C-statistic was 0.71 for the reference model (only age, sex and race/ethnicity) and increased to 0.75 for the continuous and categorical polysocial score. Compared with the reference model, the integrated discrimination index for adding the continuous or categorical polysocial score was both 0.03 (P values < 0.001). Participants with an intermediate (odds ratio [OR] = 0.69; 95% confidence interval [CI], 0.51–0.82) or high (OR = 0.48; 95% CI, 0.38–0.60) polysocial score had lower odds of death than those in the low category in the fully adjusted model, respectively.

Conclusions

the polysocial approach may offer possible solutions to monitor social environments and suggestions for older people to improve their social status for specific health outcomes.
Relationship between Fried’s frailty phenotype and oral frailty in long-term care residents
Authors: Hiltunen Kaija , Saarela Riitta K T , Kautiainen Hannu , Roitto Hanna-Maria , Pitkälä Kaisu H , Mäntylä Päivi
Published: August 2021

Background

oral frailty (OFr) may be called a syndrome lacking a consensus on its definition.

Objective

the aim was to prove the relationship between OFr to the phenotype of frailty, general health and nutrition in long-term care.

Design

the FINnish ORAL Health Study in Long-Term Care study is a cross-sectional clinical research comprising findings on oral and general health and nutrition.

Setting

participants were divided into groups according to the number of OFr signs: Group 1 (0–1 sign), Group 2 (2–4 signs) and Group 3 (5–6 signs).

Subjects

the study includes data on 349 older residents of long-term care facilities in Helsinki, Finland.

Methods

frailty status was defined according to Fried’s frailty phenotype. OFr was evaluated with six signs: dry mouth, diet of pureed or soft food, residue of food on oral surfaces, unclear speech, inability to keep mouth open during the clinical oral examination and pain expression during the examination.

Results

a significant linear relationship across the OFr groups with Fried’s frailty phenotype was found (P for linearity = 0.008, adjusted by gender and age). A linear trend existed between OFr groups and general health; prevalence of dementia and malnutrition increased from Group 1 to Group 3. The need for help with eating and oral hygiene procedures increased from Group 1 to Group 3. Moreover, OFr had a linear relationship with chewing and swallowing difficulties.

Conclusions

OFr is related to Fried’s frailty phenotype, general health, nutrition and need for help with daily activities.
Presenilin 1 Gene Mutation (M139V) in a German Family with Early-Onset Alzheimer’s Disease: A Case Report
Authors: Fuentes Manuel , Schipke Carola G , Freiesleben Silka Dawn , Klostermann Arne , Peters Oliver
Published: August 2021

Objective

This study describes a 44-year-old German male with early-onset Alzheimer’s disease as a result of a M139V presenilin 1 mutation. The patient has at least seven affected family members, spanning at least four generations.

Method

We performed a complete demographic, genetic, neuropsychological, neuropsychiatric, neuroradiological, and neuropathological characterizations of this patient. The findings were compared with previous reports of patients with the same mutation. Demographic, neuropsychological, neuropsychiatric, neuroradiological, and neuropathological data from several affected members of the patient’s family were also addressed.

Results

We describe similarities shared with other cases, including age at onset, rapid disease progression, severe deficits in arithmetic and visuo-constructive abilities with relative preservation of naming skills, and the presence of predominant frontal behavioral symptoms. Differences with respect to previously described cases, including the absence of positive neurological or radiological findings, psychotic symptoms, or a depressive disorder, are also identified and discussed.

Conclusions

Heterogeneity in symptoms between affected patients from the same or from different families suggests that individual, genetic, or epigenetic factors most likely modulate the phenotype of patients carrying the M139V mutation.
Domestic Violence and Whole Family Interventions: Charting Change in the Lives of Service Users
Authors: Spratt Trevor , Swords Lorraine , Hanlon Holly
Published: August 2021

In this article we report the results of the introduction of measures to ascertain the impact of therapeutic services for families where domestic violence has taken place. The setting is a specialist service for families located in Dublin, Ireland. The overall goal of the intervention was the ending of violence. To help achieve this, therapies sought to reduce conflict, promote better parental mental health and improve the quality of relationships between parents and children. Using validated instruments, measures were taken at Time 1 (entering service) from seventy-one mothers and forty fathers. At the time of data analysis for this article thirty-seven mothers and twenty-four fathers had completed the Time 2 (leaving service) surveys. Results indicate significant reduction in conflict between participating partners, and improvements in parental mental health and quality of parent–child relationships. These results add support to the view that whilst intervention goals must include the cessation of domestic violence, this can only be achieved with due attention to the complexity of the causes. The use of validated instruments is helpful in seeking to establish outcomes measures that may supplement more traditional measures of efficacy of interventions within specialist services.
Effects of statins on dopamine loss and prognosis in Parkinson’s disease
Authors: Jeong Seong Ho , Lee Hye Sun , Chung Seok Jong , Yoo Han Soo , Jung Jin Ho , Baik Kyoungwon , Lee Yang Hyun , Sohn Young H , Lee Phil Hyu
Published: August 2021

Statins are more widely used not only for the primary and secondary prevention of cardiovascular disease by blocking cholesterol biosynthesis but also for the potential neuroprotective agents during neurological disorders due to their pleiotropic effects. In this study, we investigate whether the previous use of statins affect baseline nigrostriatal dopamine loss at the time of diagnosis and longitudinal motor and cognitive outcomes in patients with Parkinson’s disease.

Five hundred drug-naïve patients with Parkinson’s disease who underwent dopamine transporter imaging were classified into two groups according to the prior use of statins: patients with and without statin use. Multivariate linear regression was used to determine intergroup differences in dopamine transporter availability. We evaluated the longitudinal changes in levodopa-equivalent dose and dementia conversion between the groups using a linear mixed model and survival analysis, respectively. In addition, mediation analysis was applied to examine the effect of total cholesterol.

Patients with Parkinson’s disease treated with statins had a lower baseline dopamine transporter availability in the anterior (2.13 ± 0.55 versus 2.37 ± 0.67; P = 0.002), posterior (1.31 ± 0.43 versus 1.49 ± 0.54; P = 0.003) and ventral putamina (1.40 ± 0.39 versus 1.56 ± 0.47; P = 0.002) than that in matched patients with Parkinson’s disease without statins. After adjusting for age at symptom onset, sex, disease duration and vascular risk factors, linear regression models showed that a previous treatment with statins remained significantly and independently associated with more severely decreased dopamine transporter availability in the anterior putamen (Beta = −0.140, P = 0.004), posterior putamen (Beta = −0.162, P = 0.001) and ventral putamen (Beta = −0.140, P = 0.004). A linear mixed model revealed that patients with Parkinson’s disease being treated with statins had a faster longitudinal increase in levodopa-equivalent dose than those without. A survival analysis showed that the rate of dementia conversion was significantly higher in patients with Parkinson’s disease with statins (hazard ratio, 2.019; 95% confidence interval, 1.108–3.678; P = 0.022) than those without. Mediation analyses revealed that the effect of statin treatment on baseline dopamine transporter availability and longitudinal outcome was not mediated by total cholesterol levels.

This study suggests that statin use may have a detrimental effect on baseline nigrostriatal dopamine degeneration and long-term outcomes in patients with Parkinson’s disease.
Sensory Recruitment Revisited: Ipsilateral V1 Involved in Visual Working Memory
Authors: Zhao Yi-Jie , Kay Kendrick N , Tian Yonghong , Ku Yixuan
Published: August 2021

The “sensory recruitment hypothesis” posits an essential role of sensory cortices in working memory, beyond the well-accepted frontoparietal areas. Yet, this hypothesis has recently been challenged. In the present study, participants performed a delayed orientation recall task while high-spatial-resolution 3 T functional magnetic resonance imaging (fMRI) signals were measured in posterior cortices. A multivariate inverted encoding model approach was used to decode remembered orientations based on blood oxygen level-dependent fMRI signals from visual cortices during the delay period. We found that not only did activity in the contralateral primary visual cortex (V1) retain high-fidelity representations of the visual stimuli, but activity in the ipsilateral V1 also contained such orientation tuning. Moreover, although the encoded tuning was faded in the contralateral V1 during the late delay period, tuning information in the ipsilateral V1 remained sustained. Furthermore, the ipsilateral representation was presented in secondary visual cortex (V2) as well, but not in other higher-level visual areas. These results thus supported the sensory recruitment hypothesis and extended it to the ipsilateral sensory areas, which indicated the distributed involvement of visual areas in visual working memory.
Partially Preserved Processing of Musical Rhythms in REM but Not in NREM Sleep
Authors: Sifuentes-Ortega Rebeca , Lenc Tomas , Nozaradan Sylvie , Peigneux Philippe
Published: August 2021

The extent of high-level perceptual processing during sleep remains controversial. In wakefulness, perception of periodicities supports the emergence of high-order representations such as the pulse-like meter perceived while listening to music. Electroencephalography (EEG) frequency-tagged responses elicited at envelope frequencies of musical rhythms have been shown to provide a neural representation of rhythm processing. Specifically, responses at frequencies corresponding to the perceived meter are enhanced over responses at meter-unrelated frequencies. This selective enhancement must rely on higher-level perceptual processes, as it occurs even in irregular (i.e., syncopated) rhythms where meter frequencies are not prominent input features, thus ruling out acoustic confounds. We recorded EEG while presenting a regular (unsyncopated) and an irregular (syncopated) rhythm across sleep stages and wakefulness. Our results show that frequency-tagged responses at meter-related frequencies of the rhythms were selectively enhanced during wakefulness but attenuated across sleep states. Most importantly, this selective attenuation occurred even in response to the irregular rhythm, where meter-related frequencies were not prominent in the stimulus, thus suggesting that neural processes selectively enhancing meter-related frequencies during wakefulness are weakened during rapid eye movement (REM) and further suppressed in non-rapid eye movement (NREM) sleep. These results indicate preserved processing of low-level acoustic properties but limited higher-order processing of auditory rhythms during sleep.
Trimethylamine N-oxide induces osteogenic responses in human aortic valve interstitial cells in vitro and aggravates aortic valve lesions in mice
Authors: Li Jiaying , Zeng Qingchun , Xiong Zhenyu , Xian Gaopeng , Liu Zuheng , Zhan Qiong , Lai Wenyan , Ao Lihua , Meng Xianzhong , Ren Hao , Xu Dingli
Published: August 2021

Aims

Recent studies have shown that the choline-derived metabolite trimethylamine N-oxide (TMAO) is a biomarker that promotes cardiovascular disease through the induction of inflammation and stress. Inflammatory responses and stress are involved in the progression of calcified aortic valve disease (CAVD). Here, we examined whether TMAO induces the osteogenic differentiation of aortic valve interstitial cells (AVICs) through endoplasmic reticulum (ER) and mitochondrial stress pathways in vitro and in vivo.

Methods and results

Plasma TMAO levels were higher in patients with CAVD (n = 69) than in humans without CAVD (n = 263), as examined by liquid chromatography–tandem mass spectrometry. Western blot and staining probes showed that TMAO-induced an osteogenic response in human AVICs. Moreover, TMAO promoted ER stress, mitochondrial stress, and nuclear factor-κB (NF-κB) activation in vitro. Notably, the TMAO-mediated effects were reversed by the use of ER stress, mitochondrial stress, and NF-κB activation inhibitors and small interfering RNA. Mice treated with supplemental choline in a high-fat diet had markedly increased TMAO levels and aortic valve thicknesses, which were reduced by 3,3-dimethyl-1-butanol (an inhibitor of trimethylamine formation) treatment.

Conclusions

Choline-derived TMAO promotes osteogenic differentiation through ER and mitochondrial stress pathways in vitro and aortic valve lesions in vivo.
Effects of lignocaine vs. opioids on antiplatelet activity of ticagrelor: the LOCAL trial
Authors: Fernando Himawan , Duong Thy , Huynh Kevin , Noonan Jonathan , Shaw James , Duffy Stephen J , Nehme Ziad , Smith Karen , Myles Paul S , Meikle Peter J , Peter Karlheinz , Stub Dion
Published: August 2021

Aims

We assessed the impact of intravenous fentanyl and lignocaine on the pharmacokinetics and pharmacodynamics of ticagrelor in patients with unstable angina and non-ST-elevation myocardial infarction and their procedural analgesic efficacy and safety.

Methods and results

Seventy patients undergoing coronary angiography with ticagrelor loading were included in the pharmacokinetic and pharmacodynamic analyses of this randomized trial. Plasma ticagrelor levels 2 h post-loading dose were significantly lower in the fentanyl arm than in the lignocaine treatment arm (598 vs. 1008 ng/mL, P = 0.014). The area under the plasma–time curves for ticagrelor (1228 vs. 2753 ng h/mL, P < 0.001) and its active metabolite (201 vs. 447 ng h/mL, P = 0.001) were both significantly lower in the fentanyl arm. Expression of activated platelet glycoprotein IIb/IIIa receptor (2829 vs. 1426 mean fluorescence intensity, P = 0.006) and P-selectin (439 vs. 211 mean fluorescence intensity, P = 0.001) was significantly higher at 60 min in the fentanyl arm. A higher proportion of patients had high on-treatment platelet reactivity in the fentanyl arm at 60 min using the Multiplate Analyzer (41% vs. 9%, P = 0.002) and 120 min using the VerifyNow (30% vs. 3%, P = 0.003) and VASP (37% vs. 6%, P = 0.002) assays. Both drugs were well tolerated with a high level of patient satisfaction.

Conclusions

Unlike fentanyl, lignocaine does not impair the bioavailability or delay the antiplatelet effect of ticagrelor. Both drugs were well tolerated and effective with a high level of patient satisfaction for procedural analgesia. Routine procedural analgesia during percutaneous coronary intervention should be reconsidered and if performed, lignocaine is a beneficial alternative to fentanyl.
Effect of dapagliflozin on ventricular arrhythmias, resuscitated cardiac arrest, or sudden death in DAPA-HF
Authors: Curtain James P , Docherty Kieran F , Jhund Pardeep S , Petrie Mark C , Inzucchi Silvio E , Køber Lars , Kosiborod Mikhail N , Martinez Felipe A , Ponikowski Piotr , Sabatine Marc S , Bengtsson Olof , Langkilde Anna Maria , Sjöstrand Mikaela , Solomon Scott D , McMurray John J V
Published: August 2021

Aims

The aim of this study was to examine the effect of dapagliflozin on the incidence of ventricular arrhythmias and sudden death in patients with heart failure and reduced ejection fraction (HFrEF).

Methods and results

In a post hoc analysis of DAPA-HF, we examined serious adverse event reports related to ventricular arrhythmias or cardiac arrest, in addition to adjudicated sudden death. The effect of dapagliflozin, compared with placebo, on the composite of the first occurrence of any serious ventricular arrhythmia, resuscitated cardiac arrest, or sudden death was examined using Cox proportional hazards models. A serious ventricular arrhythmia was reported in 115 (2.4%) of the 4744 patients in DAPA-HF (ventricular fibrillation in 15 patients, ventricular tachycardia in 86, ‘other’ ventricular arrhythmia/tachyarrhythmia in 12, and torsade de pointes in 2 patients). A total of 206 (41%) of the 500 cardiovascular deaths occurred suddenly. Eight patients survived resuscitation from cardiac arrest. Independent predictors of the composite outcome (first occurrence of any serious ventricular arrhythmia, resuscitated cardiac arrest or sudden death), ranked by chi-square value, were log-transformed N-terminal pro-B-type natriuretic peptide, history of ventricular arrhythmia, left ventricular ejection fraction, systolic blood pressure, history of myocardial infarction, male sex, body mass index, serum sodium concentration, non-white race, treatment with dapagliflozin, and cardiac resynchronization therapy. Of participants assigned to dapagliflozin, 140/2373 patients (5.9%) experienced the composite outcome compared with 175/2371 patients (7.4%) in the placebo group [hazard ratio 0.79 (95% confidence interval 0.63–0.99), P = 0.037], and the effect was consistent across each of the components of the composite outcome.

Conclusions

Dapagliflozin reduced the risk of any serious ventricular arrhythmia, cardiac arrest, or sudden death when added to conventional therapy in patients with HFrEF.

Clinical trial registration

 ClinicalTrials.gov unique identifier: NCT03036124 (DAPA-HF).
Twin-to-twin transfusion syndrome: new macroscopic and microscopic findings
Authors: Lopes Cátia , Cunha Inês , Camacho Catarina , Vareda Catarina , Lai Ana , Vilela Marisa , Mendes Fernando , Martins Diana
Published: August 2021

Background

Twin-to-twin Transfusion Syndrome (TTTS) is a serious complication of monochorionic twin pregnancies. Affects about 10% to 15% of pregnancies and it is associated with high fetal and neonatal mortality, as well as cardiac and neurological morbidity in surviving fetuses. The main objective was to characterize a series of fetuses with TTTS since the pathophysiology of the syndrome is not fully understood and the clinical spectrum is broad.

Methods

Post-mortem macroscopic and microscopic examination of 26 fetuses (from 2010 to 2020) with TTTS syndrome.

Results

The most frequent macroscopic findings in placenta were discrepancy in size and pallor/placental congestion. Other macroscopic findings not described in the literature were calcifications, areas of infarction and hematomas. Infarction areas and villi heterogeneity growth were the most common microscopic findings, described in the literature. Regarding the fetus, the restriction of intrauterine growth, the alteration of anthropometric parameters and the presence of a plethoric/anemic fetus were the main characteristics associated with this syndrome. The most common microscopic findings were signs of anoxia and congestive organs, already described in the literature. We also found frequently pulmonary abnormalities as new findings in our study.

Conclusions

The results allowed the identification of TTTS aspects that can contribute to the characterization of this syndrome. Given that the progression of TTTS remains unpredictable and the mortality rate for both fetuses is 90%, it becomes increasingly important to identify strategies for diagnosing and characterizing the syndrome.