bluuebunny/crossref_metadata_2025 huggingface dataset:
Hybridization effect on energy absorption capacity of composite crash boxes
Authors: Erkek Baran , Kosedag Ertan , Adin Hamit
Published: June 2024

Crash boxes are safety elements generally made of metallic materials and mounted on the chassis of vehicles to prevent possible injuries to driver and passengers by absorbing the energy generated during a collision and ensuring integrity of vehicle. In order to save fuel and reduce harmful gases released into the environment, the proportion of metallic materials used in vehicles is decreasing and being replaced by composite materials. While composite materials are as durable as metallic materials, they are preferred because they are lighter. In this study, circular composites consisting of glass (S1), aramid (S2), carbon (S3), and hybrid combinations of aramid‐carbon‐glass (S4), carbon‐glass‐aramid (S5), and glass‐aramid‐carbon (S6), all with epoxy resin matrices, were produced using the vacuum infusion method and investigated. Crush parameters, maximum peak loads and specific energy absorption of hybrid tubes with different fiber types and winding order were compared. S3 tube had the best energy absorption performance among all samples of 257.288 Joules, while the worst energy absorption performance was obtained for S2 tube with 30.944 Joules. Among the hybrid samples, the best result was determined as 166.50 Joule with hybrid S5. Although the energy absorption capacities of hybrid composite tubes were close to each other, they had lower results for energy absorption and specific energy absorption than S1 and S3. For specific energy absorption, as with energy absorption, the best result was obtained with S3, while the lowest result was obtained with S2.

Highlights

The aim of this study is to evaluate the performance of composite crash boxes.

The effect of fiber type and hybridization was examined.

Specific energy absorptions and maximum contact forces were compared.

Cylindrical samples were produced by vacuum infusion.

The variation of damage depending on fiber type was investigated.
Assessing the consequences of water retention on the structural integrity of jute fiber and its composites: A review
Authors: Islam Shahidul , Karim Fahmida‐E‐ , Islam Md. Redwanul
Published: June 2024

Researchers have compared natural jute fiber to synthetic fibers due to their distinct physical and mechanical properties, which have been recognized for decades. Jute fibers are a very versatile type of vegetable fibers widely used in structural composites and it has also shown potential in various applications such as nanoparticles, building interior, and automotive components. However, designing jute composite parts is a challenging task due to plant origin, growth conditions, age, stem location, extraction method, and non‐uniform fiber cross section. The current review aims to provide a comprehensive analysis of the existing literature on jute fiber and its composites of water and moisture absorption behavior on their performance. The most relevant findings regarding jute fiber water and moisture absorption characteristics have been summarized and analyzed in this review paper. In addition, this article presents an overview of the main characteristics of jute fibers, several parameters influencing the characteristics of jute fibers, jute fiber reinforcement composites, impact of relative humidity, swelling properties on jute fiber composite materials, and potential future research areas are also highlighted.

Highlights

Higher growing interest of researchers for jute fiber

Factors affecting the properties of jute fibers

Various way of making jute fiber reinforced composites

Influence of moisture on its properties

Present and future areas of its upgradation
Taming the 1,5‐sigmatropic shift across protonated spirocyclic 4H‐pyrazoles
Authors: Levandowski Brian J. , Graham Brian J. , Abularrage Nile S. , Raines Ronald T.
Published: June 2024

The condensation of 1,3‐diketones with hydrazine to access 4H‐pyrazoles is a well‐established synthetic route that travels through a 4H‐pyrazol‐1‐ium intermediate. In the route to a 3,5‐diphenyl‐4H‐pyrazole containing a cyclobutane spirocycle, density functional theory calculations predict, and experiments show that the protonated intermediate undergoes a rapid 1,5‐sigmatropic shift to form a tetrahydrocyclopenta[c]pyrazole. Replacing the 3,5‐diphenyl groups with 2‐furanyl groups decreases the calculated rate of the 1,5‐sigmatropic shift by 6.2 × 105‐fold and enables the isolation of new spirocyclic 4H‐pyrazoles for click chemistry.
The impact of DOPO‐derived phosphoramides containing triazine moieties on the flame retardancy and smoke suppression properties of waterborne polyurethane
Authors: Zhu Xiangfeng , Cheng Feiyang , Si Yinsong , Wang Jun , Wang Pengcheng , Shi Chen , Han Jian
Published: June 2024

Waterborne polyurethane (WPU), which is a novel and environmentally friendly variety of polyurethane, replaces organic solvents with water. It has been extensively utilized in diverse fields encompassing coatings, textile finishing, building decoration, adhesives, plastic chemistry, and others. However, WPU is inherently flammable and releases a significant amount of smoke production during the combustion process. This research presents an original fire‐resistant Waterborne Polyurethane (WPU) with a newly‐integrated flame‐retardant component comprising a triazine phosphoramidate segment derived from 9,10‐dihydro‐9‐oxo‐10‐phosphaphenanthrene‐10‐oxide (DOPO) within its primary structure. In comparison to pure WPU, the limiting oxygen index (LOI) of flame‐retardant WPU (FRWPU) increased from 19.6% to 29.2%. In UL‐94 testing, the FRWPU film achieved a V‐0 rating with only 6% retarding component. Additionally, in cone calorimetry tests, Total Heat Release (THR), peak Heat Release Rate (pHRR), Total Smoke Production (TSP), Smoke Production Rate (SPR), and peak Carbon Monoxide Production Rate (pCOP) are decreased by 27.7%, 16.2%, 64.6%, 61.3%, and 77.8%, respectively. The greater degree of graphitization observed in the residual carbon substantially impeded heat exchange and the emission of smoke during combustion. Flame‐retardant intermediate segments greatly improved the FRWPUs' ability to suppress smoke and remain flame‐retardant. The creation and formulation of aqueous polyurethanes that are flame‐retardant can benefit greatly from the insights and references offered by this research.
Drug loading strategy of modular self‐assembly mode: Curcumin pyrimidine derivatives mediated by pH‐sensitive materials
Authors: Feng Jiankang , Wang Shuo , Liu Ying , Zhou Meng , Chai Tiantian , Zhang Mengtong , Hu Jingnan , Feng Xibing , Chu Qingxia , Shao Shihe , Shi Junhua , Lu Chichong , Jin Guofan
Published: June 2024

Chemotherapy drugs often cause various adverse reactions and affect normal tissues, so it is of great significance to design effective targeted anti‐tumor drug delivery methods. We constructed a series of self‐assembled supramolecular modular structures and explored whether they could become an effective targeted antitumor fluorescent agent. UV and fluorescence spectra show that it has fluorescence. The drug release curve was determined by dialysis method and the results showed that the release rate of PCB series composites was the highest under pH = 5. The curcumin pyrimidine derivative was embedded in the structure, and the formation of the complex was confirmed by infrared spectroscopy. The results for the cell imaging indicated that with the decrease of environmental pH value, the ability of PCB‐1 and PCB‐2 to penetrate the biofilm barrier into cells increased, suggesting that they have targeting action. The results of the cell viability test showed that PCB‐1 and PCB‐2 had a good inhibitory effect on MGC and HeLa cells. TEM showed that PCB‐1 was a regular hexahedron structure and PCB‐2 was a rod structure. In addition, the encapsulation efficiency of PCB‐1 and PCB‐2 was tested to be 86.50% and 88.57%, respectively, with drug loading rates of 27.62% and 28.38%, and Zeta potential values of +35 and +32. In conclusion, PCB‐1 and PCB‐2 are good potential anti‐tumor fluorescent agents.
Discovery and structure–activity relationship of dimesulfazet: a novel rice paddy herbicide
Authors: Furuhashi Takamasa , Fujita Takayuki , Miyazaki Takao , Ishimatsu Atsushi , Yano Tetsuhiko , Nakamura Daisuke , Maizuru Yukihiro , Kudo Takao , Masuzawa Yoshihide , Tanima Daisuke , Nakaya Yoshihiko
Published: June 2024

Dimesulfazet, a novel herbicide for use in paddy rice, was discovered during studies on haloalkylsulfonanilide derivatives. Our research revealed that cyclic sulfonamide derivatives exhibited herbicidal efficacy against paddy weeds prevalent in Japan, such as Schoenoplectiella juncoides (Roxb.) Lye. Furthermore, these derivatives showed efficacy against hard‐to‐control perennial sedges such as Eleocharis kuroguwai Ohwi. Subsequently, we converted the cyclic sulfonamide derivatives into cyclic amide derivatives, which demonstrated enhanced herbicidal activity. Among these derivatives, dimesulfazet was selected because of its exceptional efficacy against both annual and perennial sedges, while being safe for use on transplanted rice. A simple method was developed for the condensation of benzyl alcohol and cyclic amide intermediates to synthesize trifluoromethanesulfonanilide derivatives. We found that the mode of action of dimesulfazet involved the inhibition of very long‐chain fatty acid biosynthesis. Dimesulfazet represents a valuable new tool for controlling S. juncoides, including biotypes resistant to acetolactate synthase inhibitors, and other perennial sedges in rice paddies. © 2024 Society of Chemical Industry.
Large Enhancement of Intrinsic Spin Hall Conductivity of β‐W Based Alloy
Authors: Anh Nguyen Huynh Tuan , Van Binh Ho , Yen Hua Thi Hoang , Cuong Do Duc
Published: June 2024

In this work, intrinsic spin Hall conductivity of β‐W and its alloy with V has been theoretically studied by the combination of ab initio method with the tight binding method. Both two possible configurations of V in β‐W structure are fully considered and their total energy difference used to estimate the thermodynamic average SHC of alloy by using Maxwell‐Boltzmann distribution. It is found that due to the small total energy difference between two configurations, there is a significant contribution to the thermodynamic average SHC of the alloy from both configurations, which results in the average SHC of alloy being enhanced up to 12.3% compared with the pristine β‐W. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.
Comparing the intraocular pressure values obtained with a rebound tonometer (TONOVET Plus) and an indentation tonometer (IOPvet) in dogs with and without ocular disease
Authors: Michaud Bertrand , Lesne Fabien
Published: June 2024

Background

This study aimed to compare the intraocular pressure (IOP) values obtained from two groups of dogs using the IOPvet indentation tonometer to those obtained from the same dogs using an established rebound tonometer (TONOVET Plus).

Methods

Tonometry was performed on 36 dogs with ocular diseases (70 eyes; group A) and 25 healthy dogs (49 eyes; group B). First, the TONOVET Plus rebound tonometer was used. Then, one drop of oxybuprocaine hydrochloride was applied to each eye, and 1 minute later, the IOP was estimated using the IOPvet.

Results

The IOPvet was safe, well tolerated and easy to use. The instrument had a high specificity (98.5%) for identifying IOPs of 20 mmHg or less. A lack of sensitivity (67.9%) was noted when evaluating eyes with an IOP between 20 and 30 mmHg. The sensitivity (33.3%) for identifying canine eyes with an IOP of greater than 30 mmHg (n = 24) was low.

Limitations

This study lacks manometric work, which would be hard to justify with client‐owned dogs. Quantitative numerical data were compared with qualitative values and the same investigator obtained readings using both tonometers without being masked.

Conclusions

The IOPvet is highly sensitive for assessing normal IOPs, but underestimation of higher IOPs can lead to poor diagnostics. Digital tonometers remain the best way to assess IOP in veterinary clinics.
Life cycle assessment of hydrogen production, storage, and utilization toward sustainability
Authors: Osman Ahmed I. , Nasr Mahmoud , Mohamed A. R. , Abdelhaleem Amal , Ayati Ali , Farghali Mohamed , Al‐Muhtaseb Ala'a H. , Al‐Fatesh Ahmed S. , Rooney David W.
Published: June 2024

In the pursuit of sustainable energy solutions, hydrogen emerges as a promising candidate for decarbonization. The United States has the potential to sell wind energy at a record‐low price of 2.5 cents/kWh, making hydrogen production electricity up to four times cheaper than natural gas. Hydrogen's appeal stems from its highly exothermic reaction with oxygen, producing only water as a byproduct. With an energy content equivalent to 2.4 kg of methane or 2.8 kg of gasoline per kilogram, hydrogen boasts a superior energy‐to‐weight ratio compared to fossil fuels. However, its energy‐to‐volume ratio, exemplified by liquid hydrogen's 8.5 MJ.L−1 versus gasoline's 32.6 MJ.L−1, presents a challenge, requiring a larger volume for equivalent energy. In addition, this review employs life cycle assessment (LCA) to evaluate hydrogen's full life cycle, including production, storage, and utilization. Through an examination of LCA methodologies and principles, the review underscores its importance in measuring hydrogen's environmental sustainability and energy consumption. Key findings reveal diverse hydrogen production pathways, such as blue, green, and purple hydrogen, offering a nuanced understanding of their life cycle inventories. The impact assessment of hydrogen production is explored, supported by case studies illustrating environmental implications. Comparative LCA analysis across different pathways provides crucial insights for decision‐making, shaping environmental and sustainability considerations. Ultimately, the review emphasizes LCA's pivotal role in guiding the hydrogen economy toward a low‐carbon future, positioning hydrogen as a versatile energy carrier with significant potential.

This article is categorized under:

Emerging Technologies > Hydrogen and Fuel Cells
Post-inflationary leptogenesis and dark matter production: metric versus Palatini formalism
Authors: Ghoshal Anish , Lalak Zygmunt , Pal Supratik , Porey Shiladitya
Published: June 2024

Abstract

We investigate production of non-thermal dark matter particles and heavy sterile neutrinos from inflaton during the reheating era, which is preceded by a slow-roll inflationary epoch with a quartic potential and non-minimal coupling (ξ) between inflaton and gravity. We compare our analysis between metric and Palatini formalism. For the latter, the tensor-to-scalar ratio, r, decreases with ξ. We find that for ξ = 0.5 and number of e-folds ~ 60, r can be as small as ~ $$ \mathcal{O} $$
O
(10−3) which may be validated at future reaches of upcoming CMB observation such as CMB-S4 etc. We identify the permissible range of Yukawa coupling yχ between inflaton and fermionic DM χ, to be $$ \mathcal{O} $$
O
(10−3.5) ≳ yχ ≳ $$ \mathcal{O} $$
O
(10−20) for metric formalism and $$ \mathcal{O} $$
O
(10−4) ≳ yχ ≳ $$ \mathcal{O} $$
O
(10−11) for Palatini formalism which is consistent with current PLANCK data and also within the reach of future CMB experiments. For the scenario of leptogenesis via the decay of sterile neutrinos produced from inflaton decay, we also investigate the parameter space involving heavy neutrino mass MN1 and Yukawa coupling yN1 of sterile neutrino with inflaton, which are consistent with current CMB data and successful generation of the observed baryon asymmetry of the universe via leptogenesis. In contrast to metric formalism, in the case of Palatini formalism, for successful leptogenesis to occur, we find that yN1 has a very narrow allowable range and is severely constrained from the consistency with CMB predictions.
Lessons from ATLAS and CMS measurements of Higgs boson decays to second generation fermions
Authors: Nir Yosef , Udhayashankar Purvaash Panduranghan
Published: June 2024

Abstract

There is now experimental evidence for Higgs boson decay into a pair of muons, and significant constraints on the Higgs boson decay into a charm quark-antiquark pair. The data on Higgs boson decays into second generation fermions probes various extensions of the Standard Model. We analyze the implications for the Standard Model effective field theory (SMEFT), without and with minimal flavor violation (MFV), for two Higgs doublet models (2HDM) with natural flavor conservation (NFC), for models with vector-like fermions, and for specific models that predict significant modifications of the Yukawa couplings to the light generations.
Non-Nilpotent Leibniz Algebras with One-Dimensional Derived Subalgebra
Authors: Di Bartolo Alfonso , La Rosa Gianmarco , Mancini Manuel
Published: June 2024

In this paper we study non-nilpotent non-Lie Leibniz $$\mathbb {F}$$
F
-algebras with one-dimensional derived subalgebra, where $$\mathbb {F}$$
F
is a field with $${\text {char}}(\mathbb {F}) \ne 2$$

char
(
F
)
≠
2

. We prove that such an algebra is isomorphic to the direct sum of the two-dimensional non-nilpotent non-Lie Leibniz algebra and an abelian algebra. We denote it by $$L_n$$

L
n

, where $$n=\dim _\mathbb {F}L_n$$

n
=

dim
F

L
n

. This generalizes the result found in Demir et al. (Algebras and Representation Theory 19:405-417, 2016), which is only valid when $$\mathbb {F}=\mathbb {C}$$

F
=
C

. Moreover, we find the Lie algebra of derivations, its Lie group of automorphisms and the Leibniz algebra of biderivations of $$L_n$$

L
n

. Eventually, we solve the coquecigrue problem for $$L_n$$

L
n

by integrating it into a Lie rack.
Redox regulation of UPR signalling and mitochondrial ER contact sites
Authors: Casas-Martinez Jose C. , Samali Afshin , McDonagh Brian
Published: June 2024

Mitochondria and the endoplasmic reticulum (ER) have a synergistic relationship and are key regulatory hubs in maintaining cell homeostasis. Communication between these organelles is mediated by mitochondria ER contact sites (MERCS), allowing the exchange of material and information, modulating calcium homeostasis, redox signalling, lipid transfer and the regulation of mitochondrial dynamics. MERCS are dynamic structures that allow cells to respond to changes in the intracellular environment under normal homeostatic conditions, while their assembly/disassembly are affected by pathophysiological conditions such as ageing and disease. Disruption of protein folding in the ER lumen can activate the Unfolded Protein Response (UPR), promoting the remodelling of ER membranes and MERCS formation. The UPR stress receptor kinases PERK and IRE1, are located at or close to MERCS. UPR signalling can be adaptive or maladaptive, depending on whether the disruption in protein folding or ER stress is transient or sustained. Adaptive UPR signalling via MERCS can increase mitochondrial calcium import, metabolism and dynamics, while maladaptive UPR signalling can result in excessive calcium import and activation of apoptotic pathways. Targeting UPR signalling and the assembly of MERCS is an attractive therapeutic approach for a range of age-related conditions such as neurodegeneration and sarcopenia. This review highlights the emerging evidence related to the role of redox mediated UPR activation in orchestrating inter-organelle communication between the ER and mitochondria, and ultimately the determination of cell function and fate.
Strong Cosmic Censorship for the Spherically Symmetric Einstein–Maxwell-Charged-Klein–Gordon System with Positive $$\Lambda $$: Stability of the Cauchy Horizon and $$H^1$$ Extensions
Authors: Rossetti Flavio
Published: June 2024

We investigate the interior of a dynamical black hole as described by the Einstein–Maxwell-charged-Klein–Gordon system of equations with a cosmological constant, under spherical symmetry. In particular, we consider a characteristic initial value problem where, on the outgoing initial hypersurface, interpreted as the event horizon

$$\mathcal {H}^+$$

H

+

of a dynamical black hole, we prescribe: (a) initial data asymptotically approaching a fixed sub-extremal Reissner–Nordström–de Sitter solution and (b) an exponential Price law upper bound for the charged scalar field. After showing local well-posedness for the corresponding first-order system of partial differential equations, we establish the existence of a Cauchy horizon

$$\mathcal{C}\mathcal{H}^+$$

C

H

+

for the evolved spacetime, extending the bootstrap methods used in the case

$$\Lambda = 0$$

Λ
=
0

by Van de Moortel (Commun Math Phys 360:103–168, 2018. https://doi.org/10.1007/s00220-017-3079-3). In this context, we show the existence of

$$C^0$$

C
0

spacetime extensions beyond

$$\mathcal{C}\mathcal{H}^+$$

C

H

+

. Moreover, if the scalar field decays at a sufficiently fast rate along

$$\mathcal {H}^+$$

H

+

, we show that the renormalized Hawking mass remains bounded for a large set of initial data. With respect to the analogous model concerning an uncharged and massless scalar field, we are able to extend the known range of parameters for which mass inflation is prevented, up to the optimal threshold suggested by the linear analyses by Costa–Franzen (Ann Henri Poincaré 18:3371–3398, 2017. https://doi.org/10.1007/s00023-017-0592-z) and Hintz–Vasy (J Math Phys 58(8):081509, 2017. https://doi.org/10.1063/1.4996575). In this no-mass-inflation scenario, which includes near-extremal solutions, we further prove that the spacetime can be extended across the Cauchy horizon with continuous metric, Christoffel symbols in

$$L^2_{\text {loc}}$$

L
loc
2

and scalar field in

$$H^1_{\text {loc}}$$

H
loc
1

. By generalizing the work by Costa–Girão–Natário–Silva (Commun Math Phys 361:289–341, 2018. https://doi.org/10.1007/s00220-018-3122-z) to the case of a charged and massive scalar field, our results reveal a potential failure of the Christodoulou–Chruściel version of the strong cosmic censorship under spherical symmetry.
Association of Constipation with Modes of Delivery: A Retrospective Questionnaire-based Study
Authors: Hierink G. Marije , Brinkman Lauret A. M. , Malmberg G. G. Alec , van Eijndhoven Hugo W. F. , Trzpis Monika , Broens Paul M. A. ,   on behalf of the LIOMOC-study group, van Wijk Tessa
Published: June 2024

Introduction and Hypothesis

Pelvic floor damage can contribute to pelvic floor dysfunction, including constipation. Most studies focus on constipation during pregnancy, whereas information regarding the mode of delivery in relation to constipation is limited. We hypothesise that women with a history of vaginal delivery report constipation more often than women with a history of caesarean section.

Methods

This was a retrospective cross-sectional multicentre study conducted in the Netherlands. All included patients (n = 2,643) completed the Groningen Defecation and Fecal Continence questionnaire to assess bowel problems of the last 6 months. Parametric tests, Chi-squared, univariable and multivariable regression analyses were performed.

Results

Among 2,643 parous women, 2,248 delivered vaginally (85.1%) and 395 (14.9%) by caesarean section. Altogether, 649 women (24.6%) suffered from constipation. Women in the vaginal delivery group were constipated more often than women in the caesarean section group (25.5% versus 19.0%, p = 0.005). For women who had delivered vaginally, multivariable regression analysis showed an odds ratio for constipation of 1.47 (95% confidence interval, 1.109–1.938, p = 0.007). The odds ratio for constipation in women with a spontaneous perineal tear was 1.4 times higher than in women with an intact perineum (p = 0.030). Furthermore, the vaginal delivery group reported difficulties regarding bowel emptying (p = 0.048), straining (p = 0.027), incomplete defecation (p = 0.043), not able to defecate daily (p = 0.018), manually assisted defecation (p = 0.015) and had higher Renzi scores (p = 0.043) more often.

Conclusions

Women in the vaginal delivery group have higher prevalences and odds ratios for constipation. Furthermore, a perineal tear during vaginal delivery increases the odds ratio for constipation.
The pros and cons of nucleic acid-amplified immunoassays—a comparative study on the quantitation of prostate-specific antigen with and without rolling circle amplification
Authors: Dekaliuk Mariia , Farka Zdeněk , Hildebrandt Niko
Published: June 2024

Integrating isothermal nucleic acid amplification strategies into immunoassays can significantly decrease analytical limits of detection (LODs). On the other hand, an amplification step adds time, complication, reagents, and costs to the assay format. To evaluate the pros and cons in the context of heterogeneous multistep immunoassays, we quantified prostate-specific antigen (PSA) with and without rolling circle amplification (RCA). In addition, we compared time-gated (TG) with continuous-wave (CW) photoluminescence (PL) detection using a terbium complex and a fluorescein dye, respectively. For both direct (non-amplified) and amplified assays, TG PL detection provided circa four- to eightfold lower LODs, illustrating the importance of autofluorescence background suppression even for multi-wash assay formats. Amplified assays required an approximately 2.4 h longer assay time but led to almost 100-fold lower LODs down to 1.3 pg/mL of PSA. Implementation of TG-FRET (using a Tb-Cy5.5 donor–acceptor pair) into the RCA immunoassay resulted in a slightly higher LOD (3.0 pg/mL), but the ratiometric detection format provided important benefits, such as higher reproducibility, lower standard deviations, and multiplexing capability. Overall, our direct comparison demonstrated the importance of biological background suppression even in heterogeneous assays and the potential of using isothermal RCA for strongly decreasing analytical LODs, making such assays viable alternatives to conventional enzyme-linked immunosorbent assays (ELISAs).

Graphical Abstract
Stenting with dual-layer CGuard stent in acute sub-occlusive carotid artery stenosis and in tandem occlusions: a monocentric study
Authors: Zidan Mousa , Gronemann Christian , Lehnen Nils Christian , Bode Felix , Weller Johannes , Petzold Gabor , Radbruch Alexander , Paech Daniel , Dorn Franziska
Published: June 2024

Purpose

Double-layer design carotid stents have been cast in a negative light since several investigations reported high rates of in-stent occlusions, at least in the acute setting of tandem occlusions. CGuard is a new generation double-layered stent that was designed to prevent periinterventional embolic events. The aim of this study was to analyze the safety and efficacy of the CGuard in emergent CAS and for the acute treatment of tandem occlusions in comparison with the single-layer Carotid Wallstent (CWS) system.

Methods

All patients who underwent CAS with CGuard or CWS after intracranial mechanical thrombectomy (MT) between 11/2018 and 12/2022 were identified from our local thrombectomy registry. Clinical, interventional and neuroimaging data were analyzed. Patency of the stent was assessed within 72 h. Intracranial hemorrhage and modified Rankin score (mRS) at discharge were the main endpoints.

Results

In total, 86 stent procedures in 86 patients were included (CWS: 44, CGuard: 42). CGuard had a lower, but not statistically significant rate (p = 0.431) of in-stent occlusions (n = 2, 4.8%) when compared to the CWS (n = 4, 9.1%). Significant in-stent stenosis was found in one case in each group. There was no statistically significant difference in functional outcome at discharge between the two groups with a median mRS for CGuard of 2 (IQR:1–5) vs. CWS 3 (IQR:2–4).

Conclusion

In our series, the rate of in-stent occlusions after emergent CAS was lower with the dual-layer CGuard when compared to the monolayer CWS. Further data are needed to evaluate the potential benefit of the design in more detail.
A Histological Assessment Tool for Breast Implant Capsules Validated in 480 Patients with and Without Capsular Contracture
Authors: Larsen Andreas , Timmermann Adam Mandrup , Kring Mikela , Weltz Tim Kongsmark , Ørholt Mathias , Vester-Glowinski Peter , Elberg Jens Jørgen , Trillingsgaard Jesper , Mielke Louise Vennegaard , Hölmich Lisbet Rosenkrantz , Damsgaard Tine Engberg , Roslind Anne , Herly Mikkel
Published: June 2024

Background

Understanding the impact of breast implants on the histological response in the surrounding fibrous capsule is important; however, consensus is lacking on how to analyze implant capsules histologically. We aimed to develop a standardized histological assessment tool to be used in research potentially improving diagnostic accuracy and treatment strategies for capsular contracture.

Methods

Biopsies of breast implant capsules from 480 patients who had undergone breast augmentation or reconstruction were collected and stained with hematoxylin and eosin. Initially, biopsies from 100 patients were analyzed to select histological parameters demonstrating the highest relevance and reproducibility. Then, biopsies from the remaining 380 patients were used to determine intra- and interobserver agreements of two blinded observers and agreement with a pathologist. Finally, we tested the association between the parameters and capsular contracture.

Results

The histological assessment tool included ten parameters assessing the inflammatory, fibrotic, and foreign-body reaction to breast implants, each graded on two-, three-, or four-point scales. Intra- and interobserver agreements were almost perfect (0.83 and 0.80), and agreement with the pathologist was substantial (0.67). Four parameters were significantly correlated with capsular contracture, namely chronic inflammation with lymphocyte infiltration (p < 0.01), thickness of the collagen layer (p < 0.0001), fiber organization (p < 0.01), and calcification (p < 0.001).

Conclusions

This is the first validated histological assessment tool for breast implant capsules. The validated tool not only advances our understanding of capsular contracture but also sets a new standard for histological evaluation in breast implant research and clinical diagnostics.

No Level Assigned

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A branching stochastic evolutionary model of the B-cell repertoire
Authors: Hyrien Ollivier , Yanev Nikolay M.
Published: June 2024

We propose a stochastic framework to describe the evolution of the B-cell repertoire during germinal center (GC) reactions. Our model is formulated as a multitype age-dependent branching process with time-varying immigration. The immigration process captures the mechanism by which founder B cells initiate clones by gradually seeding GC over time, while the branching process describes the temporal evolution of the composition of these clones. The model assigns a type to each cell to represent attributes of interest. Examples of attributes include the binding affinity class of the B cells, their clonal family, or the nucleotide sequence of the heavy and light chains of their receptors. The process is generally non-Markovian. We present its properties, including as $$t\rightarrow \infty $$

t
→
∞

when the process is supercritical, the most relevant case to study expansion of GC B cells. We introduce temporal alpha and beta diversity indices for multitype branching processes. We focus on the dynamics of clonal dominance, highlighting its non-stationarity, and the accumulation of somatic hypermutations in the context of sequential immunization. We evaluate the impact of the ongoing seeding of GC by founder B cells on the dynamics of the B-cell repertoire, and quantify the effect of precursor frequency and antigen availability on the timing of GC entry. An application of the model illustrates how it may help with interpretation of BCR sequencing data.
Modern vegetation and its pollen spectra in the Cantabrian mountains, northern Iberian Peninsula, compared with fossil pollen records
Authors: Sánchez-Morales Marc , Pérez-Obiol Ramon , Carracedo Virginia , Nadal Jordi , Ejarque Ana , Pèlachs Albert
Published: June 2024

The study of the pollen rain from modern vegetation has greatly improved the interpretation of pollen diagrams and our understanding of ancient plant communities. In this study, 76 pollen samples were studied from various vegetation types in Cantabria, northern Iberian Peninsula. The pollen signals of the main taxa were compared to their estimated spatial coverage at various scales (100 m, 1 km and 5 km from the sampling point) using vegetation maps. Additionally, we investigated whether there were similar modern vegetation types to past ones interpreted from the pollen record from La Molina peatland, Cantabria. Our results revealed that the pollen rain from the laurel-evergreen oak community (Lauro nobilis-Quercetum ilicis) was mainly evergreen Quercus pollen (59–77%), with Laurus nobilis being very under-represented. The representation of Fagus sylvatica pollen varied according to its local presence. In the modern vegetation, two sample sites with over 95% cover of Fagus within a 100 m radius had a pollen content below 3%. Pine demonstrated high dispersal capability, with pollen values exceeding 20% even in samples with little or no pine cover within 1 and 5 km. Poaceae had limited representation, with up to 60% even in samples lacking tree cover within a 5 km radius. Mixed deciduous woodlands were dominated by deciduous Quercus and Corylus, and their resemblance to woods in the northern Iberian Peninsula during the mid Holocene is discussed. While a principal component analysis linked modern vegetation to the most recent part of the pollen diagram from La Molina, no clear parallels emerged between present-day and ancient vegetation. Finally, it was found that there were no differences in pollen concentrations trapped by acrocarpous and pleurocarpous mosses.
Corresponding planktivore and predator spatial distributions in an oceanic coral reef system
Authors: Skinner Christina , Gallimore Samantha , Polunin Nicholas V. C. , Rushton Stephen , Newman Steven P. , Desbiens Amelia A. , Mill Aileen C.
Published: June 2024

Understanding the drivers of food web community structure is a fundamental goal in ecology. While studies indicate that many coral reef predators depend on pelagic subsidies, the mechanism through which this occurs remains elusive. As many of these species are important fishery targets, a better understanding of their trophodynamics is needed. To address these gaps, we employed a comprehensive structural equation modelling approach using extensive surveys of the reef community to explore relationships between groupers and snappers, their prey, and the surrounding habitat in an oceanic coral reef system. There were significant positive relationships between site-attached and transient planktivores and grouper and snapper biomass, respectively, indicating that pelagic subsidies are transferred to upper trophic levels through planktivores. Contrary to previous studies, habitat complexity and depth were not important for predators or prey. Instead, corallivores and site-attached and transient planktivores were primarily associated with live habitat and coral cover. This indicates that a decline in coral cover could have severe direct and indirect impacts on the structure and functioning of multiple levels of the reef food web. While pelagic reliance may suggest that predators are resilient to bleaching-related habitat loss, the associations of their planktivorous prey with live coral suggest that both benthic and pelagic pathways should be preserved for continued resilience of these food webs and their fisheries. By considering direct and indirect relationships, our study generated insights not only on the complex dynamics of coral reef ecosystems, but also on how they may respond to environmental change.
Predicting the presence of 4th ventricular outlet obstruction in Chiari I Malformation
Authors: Paik Kenneth S. , Caudill Caroline , Arynchyna-Smith Anastasia , Rocque Brandon G. , Rozzelle Curtis J.
Published: June 2024

Introduction

A subset of children with Chiari 1 malformation (CM-1) have a 4th ventricle arachnoid veil—a thin membrane covering the outlet of the 4th ventricle. Studies suggest that failure to disrupt this veil during posterior fossa decompression can reduce the likelihood of syringomyelia resolution. However, there is no reliable method for predicting the presence of the veil without direct surgical exploration. This study aims to evaluate the association between pre-operative symptoms, radiographic measurements, and the arachnoid veil.

Methods

A retrospective review of an institutional database of children evaluated for CM-I was conducted. For patients treated with surgery, operative notes were reviewed to determine if an arachnoid veil was present. Logistic regression was used to test for relationship of clinical variables and radiographic measurements with the presence of an arachnoid veil.

Results

Out of 997 children with CM-1, 226 surgical patients were included in the analysis after excluding those with inadequate documentation. An arachnoid veil was found in 23 patients (10.2%). Larger syrinx, spinal canal, and thecal sac diameters were significantly associated with the presence of a veil, with odds ratios of 1.23 (95% CI 1.2–1.48; p = 0.03), 1.27 (95% CI 1.02–1.59; p = 0.03), and 1.35 (95% CI 1.03–1.77; p = 0.03), respectively. No significant associations were found with any signs or symptoms.

Conclusions

Arachnoid veil was present in 10% of cases. Radiographic measurements indicating larger syrinx size were the only variables found to be significantly associated with an arachnoid veil. Exploration of the 4th ventricular outlet is recommended for CM-I decompression in the setting of expansile syringomyelia.
Do people with cognitive impairment benefit from cochlear implants? A scoping review
Authors: Dawes Piers , Cross Hannah , Millman Rebecca , Leroi Iracema , Völter Christiane
Published: June 2024

Purpose

To identify and evaluate the evidence for the benefits of cochlear implants for people with cognitive impairment or dementia in terms of speech recognition, quality of life, behavioural and psychological symptoms of dementia, cognition, function in daily life, mental well-being, and caregiver burden.

Methods

Ten electronic databases were searched systematically from inception to December 2023 for studies reporting on outcomes for cochlear implants that included adults identified with cognitive impairment, mild cognitive impairment, or dementia.

Results

Thirteen studies were included in this review with a combined total of 222 cochlear implant patients with cognitive impairment, mild cognitive impairment. Two studies were non-randomised controlled design, the remainder were single group studies, case series or single case studies. Evidence suggested that people with cognitive impairment benefit in terms of improved speech recognition from cochlear implants, although they may benefit less than those with healthy cognition and the degree of benefit depends on the level of cognitive impairment. There was no evidence for increased adverse events among those with cognitive impairment. There was limited or no evidence for any other outcome.

Conclusion

People with cognitive impairment or dementia do benefit from cochlear implants. To inform policy and clinical practice, further data are needed about the broader benefits of cochlear implants for people with cognitive impairment or dementia, and referral, eligibility, and cochlear implant support needs for people with cognitive impairment and their caregivers.
Home-made low-cost dosemeter for photon dose measurements in radiobiological experiments and for education in the field of radiation sciences
Authors: Blomgren August , Tartas Adrianna , Meher Prabodha Kumar , Silverstein Samuel , Wojcik Andrzej , Brzozowska Beata
Published: June 2024

Reliable dosimetry systems are crucial for radiobiological experiments either to quantify the biological consequences of ionizing radiation or to reproduce results by other laboratories. Also, they are essential for didactic purposes in the field of radiation research. Professional dosemeters are expensive and difficult to use in exposure facilities with closed exposure chambers. Consequently, a simple, inexpensive, battery-driven dosemeter was developed that can be easily built using readily available components. Measurements were performed to validate its readout with photons of different energy and dose rate and to demonstrate the applicability of the dosemeter. It turned out that the accuracy of the dose measurements using the developed dosemeter was better than 10%, which is satisfactory for radiobiological experiments. It is concluded that this dosemeter can be used both for determining the dose rates of an exposure facility and for educational purposes.
A cohort study of 19 patients with gyrate atrophy of the choroid and retina (GACR)
Authors: Balfoort Berith M. , Van Den Broeck Filip , Brands Marion M. , van Karnebeek Clara D. , Bergen Arthur A. , van den Born L. Ingeborgh , Houtkooper Riekelt H. , Wagenmakers Margreet A. E. M. , De Zaeytijd Julie , Leroy Bart P. , Boon Camiel J. F. , Diederen Roselie M. H.
Published: June 2024

Purpose

Gyrate atrophy of the choroid and retina (GACR) is an autosomal recessive inherited metabolic disorder (IMD) characterised by progressive retinal degeneration, leading to severe visual impairment. The rapid developments in ophthalmic genetic therapies warrant knowledge on clinical phenotype of eligible diseases such as GACR to define future therapeutic parameters in clinical trials.

Methods

Retrospective chart analysis was performed in nineteen patients. Data were analysed using IBM SPSS Statistics version 28.0.1.1.

Results

Nineteen patients were included with a mean age of 32.6 years (range 8–58). Mean age at onset of ophthalmic symptoms was 7.9 years (range 3–16). Median logMAR of visual acuity at inclusion was 0.26 (range -0.18–3.00). Mean age at cataract surgery was 28.8 years (n = 11 patients). Mean spherical equivalent of the refractive error was -8.96 (range -20.87 to -2.25). Cystoid maculopathy was present in 68% of patients, with a loss of integrity of the foveal ellipsoid zone (EZ) in 24/38 eyes. Of the 14 patients treated with dietary protein restriction, the four patients who started the diet before age 10 showed most benefit.

Conclusion

This study demonstrates the severe ophthalmic disease course associated with GACR, as well as possible benefit of early dietary treatment. In addition to visual loss, patients experience severe myopia, early-onset cataract, and CME. There is a loss of foveal EZ integrity at a young age, emphasising the need for early diagnosis enabling current and future therapeutic interventions.
Imposing Dirichlet boundary conditions directly for FFT-based computational micromechanics
Authors: Risthaus Lennart , Schneider Matti
Published: June 2024

We discuss how Dirichlet boundary conditions can be directly imposed for the Moulinec–Suquet discretization on the boundary of rectangular domains in iterative schemes based on the fast Fourier transform (FFT) and computational homogenization problems in mechanics. Classically, computational homogenization methods based on the fast Fourier transform work with periodic boundary conditions. There are applications, however, when Dirichlet (or Neumann) boundary conditions are required. For thermal homogenization problems, it is straightforward to impose such boundary conditions by using discrete sine (and cosine) transforms instead of the FFT. This approach, however, is not readily extended to mechanical problems due to the appearance of mixed derivatives in the Lamé operator of elasticity. Thus, Dirichlet boundary conditions are typically imposed either by using Lagrange multipliers or a “buffer zone” with a high stiffness. Both strategies lead to formulations which do not share the computational advantages of the original FFT-based schemes. The work at hand introduces a technique for imposing Dirichlet boundary conditions directly without the need for indefinite systems. We use a formulation on the deformation gradient—also at small strains—and employ the Green’s operator associated to the vector Laplacian. Then, we develop the Moulinec–Suquet discretization for Dirichlet boundary conditions—requiring carefully selected weights at boundary points—and discuss the seamless integration into existing FFT-based computational homogenization codes based on dedicated discrete sine/cosine transforms. The article culminates with a series of well-chosen numerical examples demonstrating the capabilities of the introduced technology.
Simulation-based Analysis of the Atmospheric Pressure Plasma and Its Temperature Distribution Using Ansys Mechanical
Authors: Chwatal Simon , Parizek Harald , Waldhauser Wolfgang
Published: June 2024

This research article delves into an in-depth analysis of atmospheric pressure plasma and its temperature distribution, utilizing the finite element method (FEM) and Ansys Mechanical software. This contribution discusses the various technological applications of atmospheric pressure plasma, including surface treatment, material processing, and plasma equipment, where precise plasma and temperature behavior prediction is crucial for an optimization and innovative solutions. The simulations presented provide a detailed representation of plasma and temperature behavior, and the simulation models have been validated against experimental data, demonstrating the accuracy and reliability of the approaches used. The deviation between the simulation and the actual measurement results was a maximum of 0.87%. In addition, the implications of the findings of this research for optimizing plasma applications and future research directions are discussed. This study highlights the crucial role of simulation tools, such as Ansys Mechanical, for investigating and optimizing atmospheric pressure plasma applications.