bluuebunny/crossref_metadata_2025_split huggingface dataset:
Viscoelastic relaxation of fibroblasts over stiff polyacrylamide gels by atomic force microscopy
Authors: Moura A L D , Santos W V , Sousa F D , Freire R S , de Oliveira C L N , de Sousa J S 
Published: August 2023

Abstract
Cell viscoelasticity provides mechanistic insights into fundamental biological functions and may be used in many applications. Using atomic force microscopy in time and frequency domains, we find a peculiar behavior in the viscoelastic relaxation of L929 mouse fibroblasts that may help understand how cells perceive and adapt to distinct extracellular environments. They are stiffer when cultured over polyacrylamide gels (20-350 kPa) than over glass-bottom Petri dishes. The stiffness enhancement of cells over gels is attributed to a significant increase in the low-frequency storage shear moduli compared to the loss moduli, indicating that gels induce a remodeling of cytoskeleton components that store elastic energy. Morphological alterations are then expressed by the fractal dimension measured on confocal images of the f-actin cytoskeleton. We show a direct scaling between the fractal dimension and the substrate’s rigidity.
A temporally and spatially local spike-based backpropagation algorithm to enable training in hardware
Authors: Biswas Anmol , Saraswat Vivek , Ganguly Udayan 
Published: August 2023

Abstract
Spiking neural networks (SNNs) have emerged as a hardware efficient architecture for classification tasks. The challenge of spike-based encoding has been the lack of a universal training mechanism performed entirely using spikes. There have been several attempts to adopt the powerful backpropagation (BP) technique used in non-spiking artificial neural networks (ANNs): (1) SNNs can be trained by externally computed numerical gradients. (2) A major advancement towards native spike-based learning has been the use of approximate BP using spike-time dependent plasticity with phased forward/backward passes. However, the transfer of information between such phases for gradient and weight update calculation necessitates external memory and computational access. This is a challenge for standard neuromorphic hardware implementations. In this paper, we propose a stochastic SNN based back-prop (SSNN-BP) algorithm that utilizes a composite neuron to simultaneously compute the forward pass activations and backward pass gradients explicitly with spikes. Although signed gradient values are a challenge for spike-based representation, we tackle this by splitting the gradient signal into positive and negative streams. The composite neuron encodes information in the form of stochastic spike-trains and converts BP weight updates into temporally and spatially local spike coincidence updates compatible with hardware-friendly resistive processing units. Furthermore, we characterize the quantization effect of discrete spike-based weight update to show that our method approaches BP ANN baseline with sufficiently long spike-trains. Finally, we show that the well-performing softmax cross-entropy loss function can be implemented through inhibitory lateral connections enforcing a winner take all rule. Our SNN with a two-layer network shows excellent generalization through comparable performance to ANNs with equivalent architecture and regularization parameters on static image datasets like MNIST, Fashion-MNIST, Extended MNIST, and temporally encoded image datasets like Neuromorphic MNIST datasets. Thus, SSNN-BP enables BP compatible with purely spike-based neuromorphic hardware.
Efficacy of Acellular Dermal Matrix Type in Treatment of Capsular Contracture in Breast Augmentation: A Systematic Review and Meta-Analysis
Authors: Samuels Kaitlyn , Millet Emily , Wong Lesley 
Published: August 2023

Abstract

Background
Capsular contracture is a known complication of breast augmentation and is among the top reasons for revisional breast augmentation procedures. The use of acellular dermal matrix (ADM) has been shown to reduce the rate of capsular contracture in breast reconstruction and augmentation, theorizing that it acts as a protective barrier between the implant capsule and inflammatory process responsible for capsular contracture. The role of ADM in treatment of capsular contracture has been investigated in numerous studies, with a variety of ADMs.

Objectives
The aim of this study was to perform a systematic review of existing literature on the use of ADM for treatment of capsular contracture in aesthetic breast augmentation patients to investigate differences in efficacy of ADM types.

Methods
The PubMed, Embase, and CINAHL databases were systematically reviewed for articles pertaining to capsular contracture, acellular dermal matrices, and breast augmentation. Number of patients, type of ADM, Baker grade, follow-up time, complication rate, and capsular contracture rate were recorded from identified articles. Data was pooled from studies to calculate a capsular contracture rate for each ADM type, with a chi-squared test performed for analysis. Identified studies with a comparative group were included in a meta-analysis utilizing risk ratio (RR) to assess the efficacy of ADM.

Results
Nine articles including ADM for treatment of capsular contracture in breast augmentation met criteria for inclusion, with a total of 481 breasts. Strattice was the most commonly utilized ADM (n = 391), followed by AlloDerm (n = 57). There was a statistically significant difference in efficacy of ADM among the studied ADM types (P &lt; .001). AlloDerm, FlexHD, and DermaMatrix had the lowest capsular contracture rates (0%). NeoForm and SurgiMend had the highest capsular contracture rates (each 25%, but with n = 4 and n = 8, respectively). Strattice had a capsular contracture rate of 1.53% in the pooled data, and meta-analysis showed that Strattice reduced the risk of capsular contracture (RR 0.14 [95% CI 0.06, 0.31]) compared with conventional treatment.

Conclusions
Acellular dermal matrices appear to be effective at treating capsular contracture after breast augmentation while maintaining a low complication rate. Overall capsular contracture rates are low with the use of ADM. There is a statistically significant difference in efficacy among ADM types. Meta-analysis shows that Strattice is effective at reducing the risk of capsular contracture in breast augmentation patients when compared to conventional treatment. Future research, especially in the form of randomized controlled trials, is needed to further investigate the efficacy of various ADMs in the treatment of capsular contracture.

Level of Evidence: 4
Diversity and evolution of telomeric motifs and telomere DNA organization in insects
Authors: Lukhtanov Vladimir A , Pazhenkova Elena A 
Published: August 2023

Abstract
The telomerase mechanism and telomeric motifs are vital for maintaining chromosome integrity. Their functions are conserved in eukaryotic organisms; therefore, it is not surprising that the structure of telomeric motifs is stable. For example, the TTAGG motif persists for hundreds of millions of years in most insects and other arthropods. Here we describe bursts of high diversity of telomeric motifs that have evolved independently in pentatomomorphic bugs (Hemiptera, Pentatomomorpha) and several lineages of parasitic and stinging wasps and bees (Hymenoptera, Apocrita). We show that in most insects, the telomeric DNA sequence is not just a collection of short repeats, but a very long array consisting of (TTAGG)n (or other motifs such as TTGGG, TCAGG, TCTGGG, TTAGGGATGG, TTAGGGGTGG, TTAGGGTGGT, TTAGGTCTGGG, TTAGGTTGGGG, TTAGGTTTGGG and TTGGGTCTGGG), regularly and specifically interrupted by the insertion of non-long terminal repeat (non-LTR) retrotransposons of the TRAS and SART families. Long (173–381 bp) repeats were found at chromosome ends in flies of the families Syrphidae and Tachinidae (Diptera). We hypothesize that the balance of telomerase-dependent machinery and telomerase-independent mechanisms (such as SART and TRAS transpositions) maintains telomeres in many insects. We also discuss how shifting this balance can lead to an increased variability of telomeric motifs and to their complete disappearance.
Activation of endothelial TRPM2 exacerbates blood–brain barrier degradation in ischemic stroke
Authors: Zong Pengyu , Feng Jianlin , Li Cindy X , Jellison Evan R , Yue Zhichao , Miller Barbara , Yue Lixia 
Published: August 2023

Abstract

Aims
Damage of the blood–brain barrier (BBB) is a hallmark of brain injury during the early stages of ischemic stroke. The subsequent endothelial hyperpermeability drives the initial pathological changes and aggravates neuronal death. Transient receptor potential melastatin 2 (TRPM2) is a Ca2+-permeable nonselective cation channel activated by oxidative stress. However, whether TRPM2 is involved in BBB degradation during ischemic stroke remains unknown. We aimed to investigate the role of TRPM2 in BBB degradation during ischemic stroke and the underlying molecular mechanisms.

Methods and results
Specific deletion of Trpm2 in endothelial cells using Cdh5 Cre produces a potent protective effect against brain injury in mice subjected to middle cerebral artery occlusion (MCAO), which is characterized by reduced infarction size, mitigated plasma extravasation, suppressed immune cell invasion, and inhibited oxidative stress. In vitro experiments using cultured cerebral endothelial cells (CECs) demonstrated that either Trpm2 deletion or inhibition of TRPM2 activation attenuates oxidative stress, Ca2+ overload, and endothelial hyperpermeability induced by oxygen–glucose deprivation (OGD) and CD36 ligand thrombospondin-1 (TSP1). In transfected HEK293T cells, OGD and TSP1 activate TRPM2 in a CD36-dependent manner. Noticeably, in cultured CECs, deleting Trpm2 or inhibiting TRPM2 activation also suppresses the activation of CD36 and cellular dysfunction induced by OGD or TSP1.

Conclusions
In conclusion, our data reveal a novel molecular mechanism in which TRPM2 and CD36 promote the activation of each other, which exacerbates endothelial dysfunction during ischemic stroke. Our study suggests that TRPM2 in endothelial cells is a promising target for developing more effective and safer therapies for ischemic stroke.
Targeting endothelial vascular cell adhesion molecule-1 in atherosclerosis: drug discovery and development of vascular cell adhesion molecule-1–directed novel therapeutics
Authors: Pickett Jessica R , Wu Yuao , Zacchi Lucia F , Ta Hang T 
Published: August 2023

Abstract
Vascular cell adhesion molecule-1 (VCAM-1) has been well established as a critical contributor to atherosclerosis and consequently as an attractive therapeutic target for anti-atherosclerotic drug candidates. Many publications have demonstrated that disrupting the VCAM-1 function blocks monocyte infiltration into the sub-endothelial space, which effectively prevents macrophage maturation and foam cell transformation necessary for atherosclerotic lesion formation. Currently, most VCAM-1-inhibiting drug candidates in pre-clinical and clinical testing do not directly target VCAM-1 itself but rather down-regulate its expression by inhibiting upstream cytokines and transcriptional regulators. However, the pleiotropic nature of these regulators within innate immunity means that optimizing dosage to a level that suppresses pathological activity while preserving normal physiological function is extremely challenging and oftentimes infeasible. In recent years, highly specific pharmacological strategies that selectively inhibit VCAM-1 function have emerged, particularly peptide- and antibody-based novel therapeutics. Studies in such VCAM-1–directed therapies so far remain scarce and are limited by the constraints of current experimental atherosclerosis models in accurately representing the complex pathophysiology of the disease. This has prompted the need for a comprehensive review that recounts the evolution of VCAM-1–directed pharmaceuticals and addresses the current challenges in novel anti-atherosclerotic drug development.
Catheter ablation of atrial fibrillation in patients with and without hypertrophic cardiomyopathy: systematic review and meta-analysis
Authors: Ezzeddine Fatima M , Agboola Kolade M , Hassett Leslie C , Killu Ammar M , Del-Carpio Munoz Freddy , DeSimone Christopher V , Kowlgi Gurukripa N , Deshmukh Abhishek J , Siontis Konstantinos C 
Published: August 2023

Abstract

Background
Atrial fibrillation (AF) is common in hypertrophic cardiomyopathy (HCM). There is limited data regarding the outcomes of AF catheter ablation in HCM patients. In this study, we aimed to synthesize all available evidence on the effectiveness of ablation of AF in patients with HCM compared to those without HCM.

Methods and results
We systematically reviewed bibliographic databases to identify studies published through February 2023. We included cohort studies with available quantitative information on rates of recurrent atrial arrhythmias, anti-arrhythmic drug (AAD) therapy, and repeat ablation procedures after initial AF ablation in patients with vs without HCM. Estimates were combined using random-effects meta-analysis models and reported as risk ratios (RR) and 95% confidence intervals (CI). Eight studies were included in quantitative synthesis (262 HCM and 642 non-HCM patients). During median follow-up 13–54 months across studies, AF recurrence rates ranged from 13.3% to 92.9% in HCM and 7.6% to 58.8% in non-HCM patients. The pooled RR for recurrent atrial arrhythmia after the first AF ablation in HCM patients compared to non-HCM controls was 1.498 (95% CI = 1.305–1.720; P &lt; 0.001). During follow-up, HCM patients more often required AAD therapy (RR = 2.844; 95% CI = 1.713–4.856; P &lt; 0.001) and repeat AF ablation (RR = 1.544; 95% CI = 1.070–2.228; P = 0.02). The pooled RR for recurrent atrial arrhythmias after the last AF ablation was higher in patients with HCM than those without HCM (RR = 1.607; 95% CI = 1.235–2.090; P &lt; 0.001).

Conclusions
Compared to non-HCM patients, those with HCM had higher rates of recurrent atrial arrhythmias, AAD use, and need for repeat AF ablation after initial ablation of AF.
Timber yield of commercial tree species in the eastern Brazilian Amazon based on 33 years of inventory data
Authors: Reategui-Betancourt Jorge Luis , Mazzei de Freitas Lucas José , Santos Kenia Ribeiro Brito , Briceño Guido , Matricardi Eraldo Aparecido Trondoli , Ruschel Ademir Roberto , de Faria Ferreira Natália Cássia 
Published: August 2023

Abstract
Selective logging in neotropical forests has directly affected the dynamics of tree species, compromising species conservation and timber yield. Sustainable use of logged forests requires new tree recruitment and diameter growth in remaining trees to compensate for trees removed between cutting cycles. This long-term study investigated timber yields in four species groups with differing values (lower, intermediate, high, and mixed) in logged and unlogged forests in the plateau region of the Tapajós River in the eastern Brazilian Amazon. Analysis was based on two size classes: medium and large commercial-sized trees. In both forest types (logged and unlogged), we found relevant tree recruitment and changes in size classes for all value groups. Most of the recruited trees observed during the 33 years of monitoring remained in the medium size class, but they also occurred in the large size class in logged forests. Over the same period, a significant loss of timber yield was seen, resulting from high mortality among the remaining trees in both size classes due to natural processes and the aftereffects of logging. Timber yield was also seen to be influenced by species richness within the group of commercial species, and recruitment and tree diameter growth capacity to counterbalance losses from mortality of the remaining trees after logging had become restricted. Forest timber yield was mainly regulated by light-demanding species, and shade-tolerant species contributed little to timber yield during the first cut. Continuous monitoring of the remaining trees and measures to reduce tree mortality during cutting cycles can encourage growth and reduce losses in stocked trees. Additionally, the national rules for forest management in the Brazilian Amazon need to be improved to achieve long-term management sustainability.
WISDOM Project – XVII. Beam-by-beam properties of the molecular gas in early-type galaxies
Authors: Williams Thomas G , Bureau Martin , Davis Timothy A , Cappellari Michele , Choi Woorak , Elford Jacob S , Iguchi Satoru , Gensior Jindra , Liang Fu-Heng , Lu Anan , Ruffa Ilaria , Zhang Hengyue 
Published: August 2023

ABSTRACT
We present a study of the molecular gas of seven early-type galaxies with high angular resolution data obtained as part of the mm-Wave Interferometric Survey of Dark Object Masses (WISDOM) project with the Atacama Large Millimeter/submillimeter Array. Using a fixed spatial-scale approach, we study the mass surface density (Σ) and velocity dispersion (σ) of the molecular gas on spatial scales ranging from 60 to 120 pc. Given the spatial resolution of our data (20–70 pc), we characterize these properties across many thousands of individual sightlines (≈50 000 at our highest physical resolution). The molecular gas along these sightlines has a large range (≈2 dex) of mass surface densities and velocity dispersions $\approx 40~{{\ \rm per\ cent}}$ higher than those of star-forming spiral galaxies. It has virial parameters αvir that depend weakly on the physical scale observed, likely due to beam smearing of the bulk galactic rotation, and is generally supervirial. Comparing the internal turbulent pressure (Pturb) to the pressure required for dynamic equilibrium (PDE), the ratio Pturb/PDE is significantly less than unity in all galaxies, indicating that the gas is not in dynamic equilibrium and is strongly compressed, in apparent contradiction to the virial parameters. This may be due to our neglect of shear and tidal forces, and/or the combination of three-dimensional and vertical diagnostics. Both αvir and Pturb anticorrelate with the global star-formation rate of our galaxies. We therefore conclude that the molecular gas in early-type galaxies is likely unbound, and that large-scale dynamics likely plays a critical role in its regulation. This contrasts to the giant molecular clouds in the discs of late-type galaxies, that are much closer to dynamical equilibrium.
High-energy interference-free K-lines synchrotron X-ray fluorescence microscopy of rare earth elements in hyperaccumulator plants
Authors: van der Ent Antony , Brueckner Dennis , Spiers Kathryn M , Falch Ken Vidar , Falkenberg Gerald , Layet Clément , Liu Wen-Shen , Zheng Hong-Xiang , Le Jean Marie , Blaudez Damien 
Published: August 2023

Abstract
Synchrotron-based micro-X-ray fluorescence analysis (µXRF) is a nondestructive and highly sensitive technique. However, element mapping of rare earth elements (REEs) under standard conditions requires care, since energy-dispersive detectors are not able to differentiate accurately between REEs L-shell X-ray emission lines overlapping with K-shell X-ray emission lines of common transition elements of high concentrations. We aim to test REE element mapping with high-energy interference-free excitation of the REE K-lines on hyperaccumulator plant tissues and compare with measurements with REE L-shell excitation at the microprobe experiment of beamline P06 (PETRA III, DESY). A combination of compound refractive lens optics (CRLs) was used to obtain a micrometer-sized focused incident beam with an energy of 44 keV and an extra-thick silicon drift detector optimized for high-energy X-ray detection to detect the K-lines of yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), and neodymium (Nd) without any interferences due to line overlaps. High-energy excitation from La to Nd in the hyperaccumulator organs was successful but compared to L-line excitation less efficient and therefore slow (∼10-fold slower than similar maps at lower incident energy) due to lower flux and detection efficiency. However, REE K-lines do not suffer significantly from self-absorption, which makes XRF tomography of millimeter-sized frozen-hydrated plant samples possible. The K-line excitation of REEs at the P06 CRL setup has scope for application in samples that are particularly prone to REE interfering elements, such as soil samples with high concomitant Ti, Cr, Fe, Mn, and Ni concentrations.
Midbrain organoids—development and applications in Parkinson’s disease
Authors: Toh Hilary S Y , Choo Xin Yi , Sun Alfred Xuyang 
Published: August 2023

Abstract
Human brain development is spatially and temporally complex. Insufficient access to human brain tissue and inadequacy of animal models has limited the study of brain development and neurodegenerative diseases. Recent advancements of brain organoid technology have created novel opportunities to model human-specific neurodevelopment and brain diseases. In this review, we discuss the use of brain organoids to model the midbrain and Parkinson’s disease. We critically evaluate the extent of recapitulation of PD pathology by organoids and discuss areas of future development that may lead to the model to become a next-generation, personalized therapeutic strategy for PD and beyond.
Empire
Authors: Bayly Martin J. 
Published: August 2023

Abstract
Empire has traditionally been a blind spot in International Relations (IR)’s substantive and theoretical coverage, but this is no longer the case. Historical IR has been at the forefront of a ‘re-turn’ to empire in the discipline, thickening our understanding of the imperial contexts that shape the systemic, intellectual, and normative structure of contemporary world politics. This chapter surveys the contributions of this literature before offering some reflections on work yet to be done. Recent work on empire and IR has demonstrated how global modernity, and by extension the modern international system, was built on the connections that empire forged. But an overemphasis on what empire is, what it does to the world, and how it should be distinguished from other polities, obscures the global entanglements that constituted imperial power. The chapter turns attention to more relational conceptions of empire, in particular those that illuminate the patterns of resistance that empire fostered.
Barbarism and Civilization
Authors: Zhang Yongjin 
Published: August 2023

Abstract
The opposition of civilization versus barbarism has long been considered one of the most potent discursive frames of international orders in world history. The ideas of barbarism and civilization carry long and complex historical memories of shifting antithesis, symbiotic existence, and dialectic relationship in intercultural encounters, exchanges, and conflicts. Through explorations of moments of their articulation and invention in a kaleidoscope of slices of Western and Chinese history, this chapter seeks to provide an analysis of the conceptual co-evolution of barbarism and civilization in contrasting cultures and intellectual traditions with a certain level of historical granularity, to unpack the fluid webs of contested intersubjective meanings of these two ideas in historical complexity, and to tease out the historicity of these two concepts. In so doing, this chapter sketches the intricate historical construction of the opposition of barbarism versus civilization as a discursive framework for international ordering and highlights the contentious nature of such a construction in shaping contemporary international practices.