bluuebunny/crossref_metadata_2025 huggingface dataset:
Multimodel evaluation of longitudinal stream temperature gradient and dominant influencing factors in Michigan streams
Authors: Andrews Ryan M. , Hayes Daniel B. , Zorn Troy G.
Published: September 2022

Stream temperature is an important determinant of fish growth, migration, and survival and can thus impact the structure and function of stream ecosystems. Many streams in Michigan and elsewhere in North America receive groundwater inputs that help regulate instream conditions by stabilizing discharge as well as stream temperature. However, groundwater withdrawal can cause reductions in streamflow which typically results in increased summer stream temperatures. Other atmospheric and hydrologic variables (i.e., overland discharge) also impact the rate at which stream temperature changes as it flows downstream. We deployed paired up‐ and downstream water pressure and temperature loggers within 21 stream reaches throughout the state of Michigan to quantify and model relationships between stream discharge, air temperature, and longitudinal change in stream temperature (i.e., temperature gradient). Using multimodel selection criteria, we evaluated the performance of a hierarchical suite of models that predict temperature gradient as a function of potential driving variables. The multimodel selection criteria identified a best‐fitting model that was able to model the diurnal, seasonal, and annual variations in rates of longitudinal temperature fluctuations across most sample streams. Partial regression analysis indicated that proxy variables representing solar radiation at the stream surface were generally the most influential predictors of longitudinal changes in stream temperature, but air temperature and components of streamflow including groundwater input were significant predictors and important in many streams.
The form evolution and environmental adaptaion of villages along a river: A case study of the dong villages in the Gaojin‐Bazhai Valley
Authors: Gao Mengyao , Yang Jingming , Chen Song , Pan Ziyan , Zhou Zhengxu
Published: September 2022

With the overall improvement of China's rural settlements, the spatial form of villages has undergone dramatic changes. The Dong villages in the mountainous regions of southwest China are closely tied to rivers and have always maintained remarkable water adaptability even under the intense development and construction disturbances of the past 30 years, providing a direct model for the sustainable development of modern communities. This paper takes the Gaojin‐Bazhai valley, Guizhou Province, and the eight Dong villages in it as a case study, using multisource data such as high‐resolution historical satellite imagery, participatory spatial mapping, interviews with key figures, and ethnography, and integrates the research methods of spatial analysis and anthropological field surveys to trace village spatial development at three levels: valley, village, and building groups. The study reveals the interaction between the Dong villages and the water environment over a long time period, and reveals a coupled artificial–natural interaction mechanism with water adaptation as the core, which is specifically interpreted as restriction, induced, adjustment, and synergy effects. With the aim of promoting a more effective succession of this mechanism, we also propose policy recommendations for the development of the water environment in the river basin as a response to the challenges arising from the ecological and ethnological conflict brought by modernization and tourism.
Innovative urban design for low‐carbon sustainable development: Evidence from China's innovative city pilots
Authors: Jiang Nana , Jiang Wei , Chen Haibo
Published: September 2022

As a sustainable urban design, innovative city pilots offer a way for developing countries to achieve carbon reduction goals. To date, a total of 78 innovative cities have been established in China. In this context, this study examines whether innovative city construction can contribute to meet carbon mitigation targets. On the basis of expounding the mechanism of innovative city pilots on carbon emissions, the multiperiod difference in differences method is applied to investigate the average treatment effect and the mediating effect model is used to validate the transmission mechanism. The results show that innovative city pilots significantly reduce carbon emissions. Compared to nonpilot areas, the pilot areas reduce carbon emissions by 15%. Specifically, technological innovation is the primary channels for innovative city pilots to influence carbon emissions but industrial structure effect does not work. Furthermore, the superimposed effect analysis indicates that the carbon reduction effect of the city as both innovative city pilot and other pilot (low‐carbon pilot, broadband China pilot, intellectual property pilot) is greater than that of a single pilot. Results of heterogeneity analysis indicate that carbon mitigation efforts are more effective in central and western cities, nonmega cities, resource‐based cities and cities with high human capital and financial development. In addition, the pilot policy has a positive spatial spillover effects on carbon reduction in cities with geographical proximity and economic ties. These results can contribute to precisely assess the environment benefits of promoting innovative city pilot projects and provide a decision making reference for fighting climate change in the era of knowledge economy.
Progression models for repeated measures: Estimating novel treatment effects in progressive diseases
Authors: Raket Lars Lau
Published: September 2022

Mixed models for repeated measures (MMRMs) are ubiquitous when analyzing outcomes of clinical trials. However, the linearity of the fixed‐effect structure in these models largely restrict their use to estimating treatment effects that are defined as linear combinations of effects on the outcome scale. In some situations, alternative quantifications of treatment effects may be more appropriate. In progressive diseases, for example, one may want to estimate if a drug has cumulative effects resulting in increasing efficacy over time or whether it slows the time progression of disease. This article introduces a class of nonlinear mixed‐effects models called progression models for repeated measures (PMRMs) that, based on a continuous‐time extension of the categorical‐time parametrization of MMRMs, enables estimation of novel types of treatment effects, including measures of slowing or delay of the time progression of disease. Compared to conventional estimates of treatment effects where the unit matches that of the outcome scale (eg, 2 points benefit on a cognitive scale), the time‐based treatment effects can offer better interpretability and clinical meaningfulness (eg, 6 months delay in progression of cognitive decline). The PMRM class includes conventionally used MMRMs and related models for longitudinal data analysis, as well as variants of previously proposed disease progression models as special cases. The potential of the PMRM framework is illustrated using both simulated and historical data from clinical trials in Alzheimer's disease with different types of artificially simulated treatment effects. Compared to conventional models it is shown that PMRMs can offer substantially increased power to detect disease‐modifying treatment effects where the benefit is increasing with treatment duration.
Electronic Metal–Support Interaction Triggering Interfacial Charge Polarization over CuPd/N‐Doped‐C Nanohybrids Drives Selectively Electrocatalytic Conversion of Nitrate to Ammonia
Authors: Xu You , Shi Keke , Ren Tianlun , Yu Hongjie , Deng Kai , Wang Xin , Wang Ziqiang , Wang Hongjing , Wang Liang
Published: September 2022

Selective electrocatalytic nitrate‐to‐ammonia conversion holds significant potential in treatment of nitrate wastewater and simultaneously produces high‐value‐added ammonia. However, today's development of nitrate‐to‐ammonia technology remains hindered by the lack of electrocatalysts with high activity and selectivity. In this work, metal‐organic framework‐derived CuPd bimetallic nanoparticles/nitrogen‐doped carbon (CuPd/CN) hybrid nanoarrays for efficient ammonia electrosynthesis from nitrate are designed and synthesized. Systematic characterization reveals that the electronic metal–support interaction between the CuPd nanoparticles and N‐doped nanocarbon matrix could trigger interfacial charge polarization over the CuPd/CN composite and make Cu sites electron deficient, which is conducive to the adsorption of nitrate ions. Moreover, the Pd atom sites separate by Cu atoms and could catalyze the dissociation of H2O molecules to form adsorbed H species, which evolves into hydrogen radicals and behaves as the dominant reactive species in accelerating nitrate‐to‐ammonia electrocatalysis. These advantages endow the CuPd/CN nanoarrays with high faradaic efficiency (96.16%), selectivity (92.08%) as well as excellent catalytic stability for electroreduction of nitrate to ammonia.
Crossing‐Gate Rod Breakage Detection in a Railway Telemeter System Using Machine Learning
Authors: Kashiwao Tomoaki , Tanoue Hiroya , Shiraishi Noriyuki , Misaki Yuki , Ando Takashi , Ikeda Kenji , Tanaka Daisuke
Published: September 2022

Shikoku Railway Company (JR Shikoku) has installed a telemeter system whose network spreads across all the railway lines in the Shikoku area. The telemeter system monitors and collects real‐time data, e.g. current, voltage, and relay signals of railway equipment. We propose a method of detecting the breakage of a crossing‐gate rod based on big data using representative machine‐learning techniques, namely, random forest and support vector machine. Moreover, we evaluate the proposed method for rod breakage cases at seven locations and demonstrate its effectiveness and versatility. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.
Kurarinone attenuates hydrogen peroxide‐induced oxidative stress and apoptosis through activating the PI3K/Akt signaling by upregulating IGF1 expression in human ovarian granulosa cells
Authors: Li Weiwei , Yin Xiurong , Yan Yani , Liu Cong , Li Gang
Published: September 2022

Dysregulated follicular development may lead to follicular atresia, and this is associated with oxidative stress in granulosa cells. Kurarinone is a natural compound possessing multiple activities, including antioxidative ability. However, the role of kurarinone in granulosa cell damage during follicular atresia remains unknown. Human ovarian granulosa KGN cells were treated with hydrogen peroxide (H2O2) to induce cellular damage. Cytotoxicity was investigated by lactate dehydrogenase (LDH) release assay. Oxidative stress was evaluated by detection of reactive oxygen species (ROS) generation and oxidative biomarker levels. Cell apoptosis was evaluated by flow cytometry, a Cell Death Detection ELISA Kit, and a Caspase‐3 Assay Kit. The downstream target and related signaling pathway were analyzed by western blotting. Kurarinone attenuated H2O2‐induced LDH release in KGN cells. Kurarinone relieved H2O2‐induced increase in ROS generation and malondialdehyde level as well as decrease in superoxide dismutase‐1 activity and heme oxygenase 1 and NAD(P)H quinone dehydrogenase 1 mRNA levels. Kurarinone inhibited H2O2‐induced apoptosis in KGN cells. Kurarinone targeted insulin‐like growth factor 1 (IGF1) and upregulated IGF1 expression to activate the phosphatidylinositol 3‐kinase (PI3K)/protein kinase B (Akt) signaling. IGF1 silencing attenuated the suppressive effects of kurarinone on H2O2‐induced oxidative stress and apoptosis in KGN cells. In conclusion, kurarinone attenuates H2O2‐induced oxidative stress and apoptosis in KGN cells through activating the PI3K/Akt signaling by upregulating IGF1 expression, indicating the therapeutic potential of kurarinone in follicular atresia.
Multiple sacro‐coccygeal dermoid sinuses on a Thai Ridgeback
Authors: Manzanedo‐Delgado Alba , Mielke Ben , Sánchez‐Masián Daniel
Published: September 2022

A 16‐month‐old, female entire, Thai Ridgeback was presented for evaluation of a two subcutaneous, non‐painful, fluctuant masses associated with two firm tubular tracts in the soft tissue dorsal to the sacrum and proximal caudal vertebrae originating at the skin surface slightly to the right of the tail base. Physical and neurological examination was otherwise normal. Magnetic resonance imaging of the lumbosacral spine revealed two dermoid sinuses type I and type II. Surgical resection and histopathological examination confirmed the presumed diagnosis. To the authors’ knowledge, the presence of two dermoid sinuses in this location has not been previously described in a Thai Ridgeback or in another dog breed in the veterinary literature. The prognosis following surgical resection appears favourable.
Efficient and enhanced sampling of drug‐like chemical space for virtual screening and molecular design using modern machine learning methods
Authors: Goel Manan , Aggarwal Rishal , Sridharan Bhuvanesh , Pal Pradeep Kumar , Priyakumar U. Deva
Published: September 2022

Drug design involves the process of identifying and designing novel molecules that have desirable properties and bind well to a given target receptor. Typically, such molecules are identified by screening large chemical libraries for desirable physicochemical properties and binding strength with the target protein. This traditional approach, however, has severe limitations as exhaustively screening every molecule in known chemical libraries is computationally infeasible. Furthermore, currently available molecular libraries are only a minuscule part of the entire set of possible drug‐like molecular structures (drug‐like chemical space). In this review, we discuss how the former limitation is addressed by modeling virtual screening as a search space problem and how these endeavors utilize machine learning to reduce the number of required computational experiments to identify top candidates. We follow that up by discussing generative methods that attempt to approximate the entire drug‐like chemical space providing us a path to explore beyond the known drug‐like chemical space. We place special emphasis on generative models that learn the marginal distributions conditioned on specific properties or receptor structures for efficient sampling of molecules. Through this review, we aim to highlight modern machine learning based methods that try to efficiently enhance our sampling capability beyond conventional screening methods which, in turn, would benefit drug design significantly. Therefore, we also encourage further methods of development that work on such important aspects of drug design.

This article is categorized under:

Data Science > Chemoinformatics

Data Science > Artificial Intelligence/Machine Learning

Data Science > Computer Algorithms and Programming
Semi‐analytical solution of solute dispersion model in semi‐infinite media
Authors: Taghvaei Poorya , Pourshahbaz Hanif , Pu Jaan H. , Pandey Manish , Pourshahbaz Vahid , Abbasi Saeed , Tofangdar Nafiseh
Published: September 2022

The advection–dispersion equation (ADE) is one of the most widely used methods for estimating natural stream pollution at different locations and times. In this paper, variational iteration method (VIM) is utilized to obtain a semi‐analytical solution for 1D ADE in a temporally dependent solute dispersion within uniformsteady flow. Through a computational validation, the effect of different parameters such as uniform flow velocity and dispersion coefficient on the solute concentration values has been investigated. Results show that the change in velocity has a strong effect on fluid density variation. However, when the diffusion coefficient has been increased, the change in flow and velocity behaviors is negligible. To verify the proposed semianalytical solution, the results were compared to analytical solutions and errors were found to be <0.7% in all simulations.
Hybrid Immediacy: Designing with Artificial Neural Networks Through Physical Concept Modelling
Authors: Bank Mathias , Sandor Viktoria , Kraft Robby , Antholzer Stephan , Berger Martin , Fabini Tilman , Kovacs Balint , Hell Tobias , Rutzinger Stefan , Schinegger Kristina
Published: September 2022

In digital design practice, the connection and feedback between physical and digital modelling is receiving increasing attention and is seen as a source of creativity and design innovation. The authors present a workflow that supports real-time design collaboration between human and machine intelligence through physical model building. The proposed framework is investigated through a case study, where we test the direct connectivity of physical and digital modelling environments with the integration of artificial neural networks. By combining 3D capturing tools and machine learning algorithms, the research creates an instant feedback loop between human and machine, introducing a hybrid immediacy that puts physical model building back at the centre of the digitally focused design process. By fusing physical models and digital workflows, the research aims to create interactivity between data, material and designer already at the early stage of the design.
New benchmark scenarios of electroweak baryogenesis in aligned two Higgs double models
Authors: Enomoto Kazuki , Kanemura Shinya , Mura Yushi
Published: September 2022

Abstract

We discuss electroweak baryogenesis in aligned two Higgs doublet models. It is known that in this model the severe constraint from the experimental results for the electron electric dipole moment can be avoided by destructive interference among CP-violating effects in the Higgs sector. In our previous work, we showed that the observed baryon number in the Universe can be explained without contradicting current available data in a specific scenario in the same model. We here first discuss details of the evaluation of baryon number based on the WKB method taking into account all order of the wall velocity. We then investigate parameter spaces which are allowed under the current available data from collider, flavor and electric dipole moment experiments simultaneously. We find several benchmark scenarios which can explain baryon asymmetry of the Universe. We also discuss how we can test these benchmark scenarios at future collider experiments, various flavor experiments and gravitational wave observations.
Fine-tuned vs. natural supersymmetry: what does the string landscape predict?
Authors: Baer Howard , Barger Vernon , Martinez Dakotah , Salam Shadman
Published: September 2022

Abstract

A vast array of (metastable) vacuum solutions arise from string compactifications, each leading to different 4-d laws of physics. The space of these solutions, known as the string landscape, allows for an environmental solution to the cosmological constant problem. We examine the possibility of an environmental solution to the gauge hierarchy problem. We argue that the landscape favors softly broken supersymmetric models over particle physics models containing quadratic divergences, such as the Standard Model. We present a scheme for computing relative probabilities for supersymmetric models to emerge from the landscape. The probabilities are related to the likelihood that the derived value of the weak scale lies within the Agrawal et al. (ABDS) allowed window of values leading to atoms as we know them. This then favors natural SUSY models over unnatural (SUSY and other) models via a computable probability measure.
Two-loop scattering amplitude for heavy-quark pair production through light-quark annihilation in QCD
Authors: Mandal Manoj K. , Mastrolia Pierpaolo , Ronca Jonathan , Torres Bobadilla William J.
Published: September 2022

Abstract

We present the first full analytic evaluation of the scattering amplitude for the process qq → $$ Q\overline{Q} $$
Q

Q
¯

up-to two loops in Quantum Chromodynamics, for a massless (q) and a massive (Q) quark flavour. The interference terms of the one- and two-loop amplitudes with the Born amplitude, decomposed in terms of gauge invariant form factors depending on the colour and flavour structure, are analytically calculated by keeping complete dependence on the squared center-of-mass energy, the squared momentum transfer, and the heavy-quark mass. The results are expressed as Laurent series around four space-time dimensions, with coefficients given in terms of generalised polylogarithms and transcendental constants up-to weight four. Our results validate the known, purely numerical calculations of the squared amplitude, and extend the analytic knowledge, previously limited to a subset of form factors, to their whole set, coming from both planar and non-planar diagrams, up-to the second order corrections in the strong coupling constant.
New AdS3/CFT2 pairs in massive IIA with (0, 4) and (4, 4) supersymmetries
Authors: Lozano Yolanda , Macpherson Niall T. , Petri Nicolò , Risco Cristian
Published: September 2022

Abstract

We construct a new class of AdS3 × S3 × M4 solutions of massive Type IIA supergravity with (0, 4) supersymmetries and SU(3) structure. We study in detail two subclasses of these solutions. The first subclass is when M4 = S2× Σ2, with Σ2 a 2d Riemann surface, and the geometry is foliated over the Σ2. We interpret these solutions as duals to surface defect CFTs within the 6d (1, 0) CFTs dual to the AdS7 × S2 × I solutions of massive IIA supergravity. The second subclass is when M4 = 𝕋3 × I and the geometry is foliated over the interval. In this case supersymmetry is enhanced to (4, 4) in the massless limit, and the solutions are the sought-for holographic duals of (4, 4) CFTs living in two dimensional D2-NS5-D4 Hanany-Witten brane set-ups. In turn, in the massive case the solutions find an interpretation as D2-D4 branes embedded in Type I’ string theory. We construct explicit quiver gauge theories from the different brane set-ups that flow in the IR to the 2d dual CFTs dual to the solutions. We check the validity of our proposals with the matching between the field theory and holographic central charges.
Antipodal symmetry of two-loop MHV amplitudes
Authors: Liu Yu-Ting
Published: September 2022

Abstract

I present a conjecture that all two-loop MHV amplitudes in planar $$ \mathcal{N} $$
N
= 4 super-Yang-Mills theory possess an antipodal symmetry when evaluated on parity-even kinematics. The symmetry acts as a change of basis on the symbol letters, followed by the antipode operation associated with the Hopf algebra structure of multiple polylogarithms. At the symbol level, I provide the symmetry map explicitly for amplitudes with up to eight external particles, and also provide evidence at all multiplicities. Intriguingly, the map acts as an isomorphism on the normal fans of the Newton polytopes of the symbol letters. The conjectured symmetry is one of the rare known cases where the antipode map shows up in physically important examples.
Catalan Generating Functions for Generators of Uni-parametric Families of Operators
Authors: Mahillo Alejandro , Miana Pedro J.
Published: September 2022

In this paper we study solutions of the quadratic equation$$AY^2-Y+I=0$$AY2-Y+I=0whereAis the generator of a one parameter family of operator ($$C_0$$C0-semigroup or cosine functions) on a Banach spaceXwith growth bound$$w_0 \le \frac{1}{4}$$w0≤14. In the case of$$C_0$$C0-semigroups, we show that a solution, which we call Catalan generating function ofA,C(A), is given by the following Bochner integral,$$\begin{aligned} C(A)x := \int _{0}^\infty c(t) T(t)x \; \mathrm{d}t, \quad x\in X, \end{aligned}$$C(A)x:=∫0∞c(t)T(t)xdt,x∈X,wherecis the Catalan kernel,$$\begin{aligned} c(t) := \frac{1}{2\pi } \int _{\frac{1}{4}}^\infty e^{-\lambda t} \frac{\sqrt{4\lambda -1}}{\lambda } \; \mathrm{d}\lambda , \quad t>0. \end{aligned}$$c(t):=12π∫14∞e-λt4λ-1λdλ,t>0.Similar (and more complicated) results hold for cosine functions. We study algebraic properties of the Catalan kernelcas an element in Banach algebras$$L^1_{\omega }(\mathbb R^+)$$Lω1(R+), endowed with the usual convolution product,$$*$$∗and with the cosine convolution product,$$*_c$$∗c. The Hille–Phillips functional calculus allows to transfer these properties to$$C_0$$C0-semigroups and cosine functions. In particular, we obtain a spectral mapping theorem forC(A). Finally, we present some examples, applications and conjectures to illustrate our results.
SOX9 in organogenesis: shared and unique transcriptional functions
Authors: Ming Zhenhua , Vining Brittany , Bagheri-Fam Stefan , Harley Vincent
Published: September 2022

The transcription factor SOX9 is essential for the development of multiple organs including bone, testis, heart, lung, pancreas, intestine and nervous system. Mutations in the human SOX9 gene led to campomelic dysplasia, a haploinsufficiency disorder with several skeletal malformations frequently accompanied by 46, XY sex reversal. The mechanisms underlying the diverse SOX9 functions during organ development including its post-translational modifications, the availability of binding partners, and tissue-specific accessibility to target gene chromatin. Here we summarize the expression, activities, and downstream target genes of SOX9 in molecular genetic pathways essential for organ development, maintenance, and function. We also provide an insight into understanding the mechanisms that regulate the versatile roles of SOX9 in different organs.
Serum sex hormone-binding globulin is a mediator of the association between intrahepatic lipid content and type 2 diabetes: the Maastricht Study
Authors: Simons Pomme I. H. G. , Valkenburg Olivier , van de Waarenburg Marjo P. H. , van Greevenbroek Marleen M. J. , Kooi M. Eline , Jansen Jacobus F. A. , Schalkwijk Casper G. , Stehouwer Coen D. A. , Brouwers Martijn C. G. J.
Published: September 2022

Aims/hypothesis

Serum sex hormone-binding globulin (SHBG) has been proposed to act as a hepatokine that contributes to the extrahepatic complications observed in non-alcoholic fatty liver disease (NAFLD). However, it remains uncertain whether serum SHBG mediates the association between intrahepatic lipids (IHL) and type 2 diabetes. Therefore, we studied whether, and to what extent, serum SHBG mediates the association between IHL content and type 2 diabetes.

Methods

We used cross-sectional data from the Maastricht Study (n=1554), a population-based cohort study with oversampling of individuals with type 2 diabetes. Type 2 diabetes status was assessed by oral glucose tolerance test, and IHL content was measured using 3T Dixon MRI. Mediation analyses were performed to assess the role of serum SHBG in mediating the association between IHL content and type 2 diabetes.

Results

IHL content was significantly associated with type 2 diabetes in women and men (OR 1.08 [95% CI 1.04, 1.14] and OR 1.12 [95% CI 1.08, 1.17], respectively). Serum SHBG significantly mediated the association between IHL content and type 2 diabetes. The contribution of serum SHBG was higher in women (OR 1.04 [95% CI 1.02, 1.07]; proportion mediated 50.9% [95% CI 26.7, 81.3]) than in men (OR 1.02 [95% CI 1.01, 1.03]; proportion mediated 17.2% [95% CI 9.6, 27.6]). Repeat analyses with proxies of type 2 diabetes and adjustment for covariates did not substantially affect the results.

Conclusions/interpretation

In this large-scale population-based cohort study, serum SHBG was found to be a mediator of the association between IHL content and type 2 diabetes. These findings extend our understanding of the potential mechanisms by which NAFLD is a risk factor for type 2 diabetes, and further elaborate on the role of SHBG as a hepatokine.

Graphical abstract
MILP-based discrete sizing and topology optimization of truss structures: new formulation and benchmarking
Authors: Brütting Jan , Senatore Gennaro , Fivet Corentin
Published: September 2022

Discrete sizing and topology optimization of truss structures subject to stress and displacement constraints has been formulated as a Mixed-Integer Linear Programming (MILP) problem. The computation time to solve a MILP problem to global optimality via a branch-and-cut solver highly depends on the problem size, the choice of design variables, and the quality of optimization constraint formulations. This paper presents a new formulation for discrete sizing and topology optimization of truss structures, which is benchmarked against two well-known existing formulations. Benchmarking is carried out through case studies to evaluate the influence of the number of structural members, candidate cross sections, load cases, and design constraints (e.g., stress and displacement limits) on computational performance. Results show that one of the existing formulations performs significantly worse than all other formulations. In most cases, the new formulation proposed in this work performs best to obtain near-optimal solutions and verify global optimality in the shortest computation time.
Thermal experiments and analysis on adhesive cleaning of work-holding devices by grinding
Authors: Haider Syed Mustafa , Khan Sarmad Ali , Ali Muhammad Asad , Farooq Muhammad Umar , Ishfaq Kashif
Published: September 2022

In the light-activated work-holding devices, hardened adhesive residues on the fixture plate need to be removed to make it available for the subsequent work holding. There are several ways to remove the cured adhesive from the gripper, such as laser-based degradation, and softening and removing with high temperature pressured water wash. These processes are associated with the generation of carbon black, affecting transparency which compromises the efficiency of the light-activated device. A novel peripheral grinding-based cleaning process has been developed to strip the adhesive from the fixture plate. The present research is aimed to analyze the effect of variation in grinding parameters, viz., spindle speed, feed, depth of cut, and the grain size of the grinding wheel on the temperature of the adhesive being ground and cleaning of the adhesive-filled channel. Aggressive values of grinding parameters are selected to achieve the desired removal of adhesive, putting a step towards sustainability. Moreover, a comprehensive investigation of the temperature of the grinding zone and the grinding wheel is made by inspecting the effective cleaning of the cured adhesive-filled channel. Higher values of spindle speed (11.57 m/s) and feed (0.406 mm/rev) resulted in an improved, cleaned surface of the ground adhesive-filled channel. Moreover, the grinding wheel with a more prominent grain size (46/Ø0.35 mm) and porosity was proved to be more effective in the cleaning process by reducing and maintaining the grinding temperature (~52 °C) of the adhesive-filled channel.
On the numerical stability of linear barycentric rational interpolation
Authors: Fuda Chiara , Campagna Rosanna , Hormann Kai
Published: September 2022

The barycentric forms of polynomial and rational interpolation have recently gained popularity, because they can be computed with simple, efficient, and numerically stable algorithms. In this paper, we show more generally that the evaluation of any function that can be expressed as$$r(x)=\sum _{i=0}^n a_i(x) f_i\big /\sum _{j=0}^m b_j(x)$$r(x)=∑i=0nai(x)fi/∑j=0mbj(x)in terms of data values$$f_i$$fiand some functions$$a_i$$aiand$$b_j$$bjfor$$i=0,\ldots ,n$$i=0,…,nand$$j=0,\dots ,m$$j=0,⋯,mwith a simple algorithm that first sums up the terms in the numerator and the denominator, followed by a final division, is forward and backward stable under certain assumptions. This result includes the two barycentric forms of rational interpolation as special cases. Our analysis further reveals that the stability of the second barycentric form depends on the Lebesgue constant associated with the interpolation nodes, which typically grows withn, whereas the stability of the first barycentric form depends on a similar, but different quantity, that can be bounded in terms of the mesh ratio, regardless ofn. We support our theoretical results with numerical experiments.
When running is easier than walking: effects of experience and gait on human obstacle traversal in virtual reality
Authors: Hofmann Florian , Dürr Volker
Published: September 2022

Humans readily traverse obstacles irrespective of whether they walk or run, despite strong differences between these gaits. Assuming that the control of human obstacle traversal may be either gait-specific or gait-independent, the present study investigates whether previous experience in an obstacle traversal task transfers between the two gaits, and, if this was the case, whether transfer worked both ways. To this end, we conducted a within-group comparison of kinematic adjustments during human obstacle traversal in both walking and running, with distinct participant groups for the two gait sequences. Participants (n = 12/12 (f/m), avg. 25 yo) were motion captured as they traversed obstacles at walking and running speeds on a treadmill, surrounded by an immersive virtual reality (VR) environment. We find that kinematics recorded in our VR setup are consistent with that obtained in real-world experiments. Comparison of learning curves reveals that participants are able to utilize previous experience and transfer learned adjustments from one gait to another. However, this transfer is not symmetrical, with previous experience during running leading to increased success rate in walking, but not the other way round. From a range of step parameters we identified lacking toe height of the trailing leg as the main cause for this asymmetry.
Impact of coronary bifurcation angle on computed tomography derived fractional flow reserve in coronary vessels with no apparent coronary artery disease
Authors: Tsugu Toshimitsu , Tanaka Kaoru , Nagatomo Yuji , Belsack Dries , Devos Hannes , Buls Nico , Cosyns Bernard , Argacha Jean-François , De Maeseneer Michel , De Mey Johan
Published: September 2022

Objectives

Computed tomography (CT) derived fractional flow reserve (FFRCT) decreases from the proximal to the distal part due to a variety of factors. The energy loss due to the bifurcation angle may potentially contribute to a progressive decline in FFRCT. However, the association of the bifurcation angle with FFRCT is still not entirely understood. This study aimed to investigate the impact of various bifurcation angles on FFRCT decline below the clinically crucial relevance of 0.80 in vessels with no apparent coronary artery disease (CAD).

Methods

A total of 83 patients who underwent both CT angiography including FFRCT and invasive coronary angiography, exhibiting no apparent CAD were evaluated. ΔFFRCT was defined as the change in FFRCT from the proximal to the distal in the left anterior descending artery (LAD) and left circumflex artery (LCX). The bifurcation angle was calculated from three-dimensional volume rendered images. Vessel morphology and plaque characteristics were also assessed.

Results

ΔFFRCT significantly correlated with the bifurcation angle (LAD angle, r = 0.35, p = 0.001; LCX angle, r = 0.26, p = 0.02) and vessel length (LAD angle, r = 0.30, p = 0.005; LCX angle, r = 0.49, p < 0.0001). In LAD, vessel length was the strongest predictor for distal FFRCT of ≤ 0.80 (β-coefficient = 0.55, p = 0.0003), immediately followed by the bifurcation angle (β-coefficient = 0.24, p = 0.02). The bifurcation angle was a good predictor for a distal FFRCT ≤ 0.80 (LAD angle, cut-off 31.0°, AUC 0.70, sensitivity 74%, specificity 68%; LCX angle, cut-off 52.6°, AUC 0.86, sensitivity 88%, specificity 85%).

Conclusions

In vessels with no apparent CAD, vessel length was the most influential factor on FFRCT, directly followed by the bifurcation angle.

Key Points

• Both LAD and LCX bifurcation angles are factors influencing FFRCT.

• Bifurcation angle is one of the predictors of a distal FFRCTof ≤ 0.80 and an optimal cut-off value of 31.0° for the LAD and 52.6° for the LCX.

• Bifurcation angle should be taken into consideration when interpreting numerical values of FFRCT.
Influence of multi-wavelength ultrafast laser texturing and autoclave sterilization on titanium alloy-based surface wettability
Authors: Pallarés-Aldeiturriaga David , Papa Steve , Abou Khalil Alain , Pascale-Hamri Alina , Maalouf Mathieu , Di Maio Yoan , Guignandon Alain , Dumas Virginie , Sedao Xxx
Published: September 2022

Titanium alloys are widely used in bio-medical applications for their excellent bio-compatibility and superior mechanical strength. On the other hand, femtosecond laser processing is a robust versatile and industrial method widely used for surface functionalization. In this work, laser-induced periodic surface structures (LIPSS) on titanium alloy (Ti6Al4V) using different laser wavelengths of 1030 nm (IR), 515 nm (Green) and 257 nm (UV) were created and their surface wettability (physical parameter correlated with cell adhesion) was studied, in relation to sterilization process. The contact angle over LIPSS was smaller than over polished samples, with Green and UV LIPSS presenting contact angles inferior to 20$$^\circ$$

∘

and a superior stability to sterilization process.
More profound impact of CP ENSO on Australian spring rainfall in recent decades
Authors: Ma Yiling , Sun Jilin , Dong Tianyun , Yu Weidong , Dong Wenjie
Published: September 2022

Most of Australia was in severe drought from 2018 to early 2020. Here we link this drought to the Pacific and Indian Ocean sea surface temperature (SST) modes associated with Central Pacific (CP) El Niño–Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD). Over the last 20 years, the occurrence frequency of CP El Niño has increased. This study extends the previous understanding of eastern Pacific (EP) El Niño-Australian rainfall teleconnections, exhibiting that CP El Niño can bring much broader and stronger rainfall deficiencies than EP El Niño during austral spring (September–November) over the northern Australia (NAU), central inland Australia and eastern Australia (EAU). The correlations between SST fields and rainfall in three Cluster regions divided by clustering analysis also confirm this, with rainfall variability in most of Australia except southern Australia (SAU) most significantly driven by CP ENSO. Also, we demonstrate that the CP El Niño affects rainfall in extratropical EAU via the Pacific-South American (PSA) pattern. While the influence of EP El Niño is only confined in tropical NAU because its PSA pattern sits far too east to convey its variability. With the development of ENSO diversity since 2000, the footprint of El Niño on Australian rainfall has become more complex.
Sexual activity after short-stem total hip arthroplasty. Does stem size matter?
Authors: Hauer Georg , Sadoghi Patrick , Smolle Maria , Zaussinger Sabrina , Friesenbichler Joerg , Leithner Andreas , Maurer-Ertl Werner
Published: September 2022

Background

Sexual activity is an important component of quality of life. To date, no studies have examined the impact of stem design on return to sexual activity (RTS) and quality of sex life after total hip arthroplasty (THA).

Methods

A questionnaire was designed to assess preoperative and postoperative sexual habits, joint awareness and physical activity in working-age patients undergoing short-stem (n = 176) or straight-stem (n = 97) THA.

Results

No differences were noted in time until RTS based on the stem design (short stems vs. straight stems; 6 [IQR: 4–10] vs. 6 [4–10] weeks; p = 0.996). Multivariate analysis revealed that higher patient BMI (p = 0.04), female gender (p < 0.001) and lower FJS-12 (p = 0.006) were significantly associated with delayed RTS. Improved hip mobility and reduced pain mainly contribute to improved quality of sexual activity postoperatively.

Conclusion

This study, hence, indicates that stem design has no impact on time until resumption of sexual activity in patients < 65 years. Female obese individuals who are aware of their artificial joint in daily life are at increased risk of delayed RTS after surgery.

Level of evidence

Level III, retrospective cohort study.
Complications associated using the reamer–irrigator –aspirator (RIA) system: a systematic review and meta-analysis
Authors: Laubach Markus , Weimer Lucas P. , Bläsius Felix M. , Hildebrand Frank , Kobbe Philipp , Hutmacher Dietmar W.
Published: September 2022

Introduction

Complications associated with the application of the Reamer–irrigator–Aspirator (RIA) system are described in the literature. However, to date a systematic review and meta-analysis to assess prevalence of complications associated with the use of the RIA system have not been conducted.

Materials and methods

The review is registered with PROSPERO (CRD42021269982). MEDLINE, the Web of Science Core Collection, and Embase were searched from the inception to 10 August 2021. The primary objective was to assess complications and blood loss associated with the use of the RIA system.

Results

Forty-seven studies involving 1834 procedures performed with the RIA system were finally included. A total of 105 complications were reported, with a pooled estimated overall prevalence of 1.7% with a 95% confidence interval (CI) of 0.40 to 3.60, with cortex perforation being the largest reported complication with a total of 34 incidences. A significant subgroup difference was observed (p = 0.02). In subgroup 1 (bone graft harvesting), complication prevalence was 1.4% (95% CI 0.2–3.4); in subgroup 2 (clearance intramedullary canal) it was 0.7% (95% CI 0.00–6.30) and in subgroup 3 (reaming with RIA system prior to nail fixation) 11.9% (95% CI 1.80–26.40). No statistically significant difference for tibia and femur as RIA system application site was observed (CI 0.69–4.19). In studies reporting blood loss, a mean volume of 803.29 ml, a mean drop of hemoglobin of 3.74 g/dl and a necessity of blood transfusion in 9.72% of the patients were observed.

Conclusions

The systematic review and meta-analysis demonstrate a low overall prevalence rate of complications associated with the RIA system. However, especially the risk of cortical perforation and the frequently reported relevant intraoperative blood loss are complications that should be anticipated in perioperative management and ultimately considered when using the RIA system.
Evaluation of fractional carbon dioxide laser alone versus its combination with betamethasone valerate in treatment of alopecia areata, a clinical and dermoscopic study
Authors: Halim Dalia Abdel , Nayer Mariam , El-Samanoudy Solwan Ibrahim , Raheem Heba Mohamed Abdel , Ragab Nanis
Published: September 2022

Alopecia areata (AA) is a non-scarring tissue-specific autoimmune disorder. Many therapeutic modalities are available for the treatment of AA, but none has yet proven to be uniformly effective. Fractional carbon dioxide (FRCO2) laser has been introduced as a treatment modality for AA. The objective is to evaluate and compare the efficacy and safety of FRCO2laser in treatment of AA alone or in combination with betamethasone valerate cream. 30 patients were assigned to one of the following groups, Group A FRCO2, Group B FRCO2plus betamethasone valerate cream or Group C (betamethasone valerate cream). Patients received eight laser sessions 2 weeks apart, treatment period was 4 months. A statistically significant decrease in SALT score, dystrophic hair and a statistically significant increase in terminal hair was observed in all groups. Patient satisfaction level and reduction in SALT score were significantly higher among FRCO2and FRCO2plus betamethasone valerate group. However, no statistical significant difference was found between FRCO2group and FRCO2combined with betamethasone valerate cream group. FRCO2laser is a safe and effective treatment modality for AA when used alone or in combination with betamethasone valerate cream. However, it was found superior to betamethasone valerate cream monotherapy.
Habituation of changed acoustics properties after canal wall down mastoidectomy
Authors: Zwemstra M. R. , Brienesse P. , de Wolf M. J. F. , van Spronsen E.
Published: September 2022

Purpose

Our objective is to evaluate the effect of habituation on the altered ear canal acoustics after canal wall down mastoidectomy.

Methods

A total of 11 participants with single sided dry cavities and normal contralateral ear canals with normal hearing thresholds were included in the study. Filtered sound fragments were created that simulate the different acoustic properties based on the participants Real Ear to Coupler Difference (RECD) of the cavity ear and the contralateral normal ear canal. These filtered sound fragments are presented to the cavity ear canal and the contralateral normal ear canal using inserts earphones. Participants performed a subjective quality assessment of the sound fragments using paired comparison with a seven-point scale (− 3 till + 3).

Results

Mean assessment of sound quality revealed the following results; naturalness of sounds of the cavity ear canal is 0.29 (± 1.41; ns) in favour of the filtered sound fragment of the normal ear canal. Mean assessment of sharpness of sounds in the cavity ear canal is 1.55 (± 1.21, p = 0.55) in favour of the filtered sound fragment of the normal ear canal. Overall preference in the cavity ear canal was in favour of the normal ear canal acoustics 0.72 (SD ± 1.54 p = 0.224).

Conclusions

Patients with cavity ear canals seem to habituate to their altered ear canal acoustics. Transforming the ear canal acoustics of the cavity ear to normal ear canal acoustics seem to sharpen the incoming sounds. Overall assessment of quality of sound of the normal ear canal acoustics is better than the cavity acoustics.
Using clustering algorithms to examine the association between working memory training trajectories and therapeutic outcomes among psychiatric and healthy populations
Authors: Agassi Or David , Hertz Uri , Shani Reut , Derakshan Nazanin , Wiener Avigail , Okon-Singer Hadas
Published: September 2022

Working memory (WM) training has gained interest due to its potential to enhance cognitive functioning and reduce symptoms of mental disorders. Nevertheless, inconsistent results suggest that individual differences may have an impact on training efficacy. This study examined whether individual differences in training performance can predict therapeutic outcomes of WM training, measured as changes in anxiety and depression symptoms in sub-clinical and healthy populations. The study also investigated the association between cognitive abilities at baseline and different training improvement trajectories. Ninety-six participants (50 females, mean age = 27.67, SD = 8.84) were trained using the same WM training task (duration ranged between 7 to 15 sessions). An algorithm was then used to cluster them based on their learning trajectories. We found three main WM training trajectories, which in turn were related to changes in anxiety symptoms following the training. Additionally, executive function abilities at baseline predicted training trajectories. These findings highlight the potential for using clustering algorithms to reveal the benefits of cognitive training to alleviate maladaptive psychological symptoms.