bluuebunny/crossref_metadata_2025 huggingface dataset:
NAO Signal in the Increased Interannual Variability of Spring Vegetation in Northeast Asia After the Early 2000s
Authors: Xin Ning , Zhou Botao , Chen Haishan , Sun Shanlei , Yu Miao
Published: November 2024

Based on the leaf area index (LAI) and normalized difference vegetation index (NDVI) from 1982 to 2020, this study reveals a significant increase in the intensity of interannual variability (IIV) in spring (April–May) vegetation over Northeast Asia since the early 2000s. This change is closely linked to the notable increase in the IIV of April surface air temperatures over Northeast Asia from the former period (1986–2001) to the latter period (2002–2016). Further analysis also highlights a salient impact of the North Atlantic Oscillation (NAO) on the strengthened IIV in vegetation. During the latter period, there is a substantial increase in the IIV of the March NAO compared with the former period. This greater variability allows the positive NAO to significantly influence the net heat fluxes, thereby leading to a positive phase of the North Atlantic tripole (NAT) sea surface temperature (SST) pattern in March. Given the persistence of SSTs, the positive NAT SST pattern lasts to April, subsequently causing positive height anomalies over Northeast Asia through a wave train that originates from the North Atlantic and propagates downstream. This process consequently results in an increase in surface air temperature over Northeast Asia and hence the local vegetation. Thus, the increased IIV of the March NAO is conducive to enhancing the IIV in spring vegetation over Northeast Asia.
Tumor budding and lymphovascular invasion as prognostic factors in p16-positive oropharyngeal squamous cell carcinomas
Authors: Stögbauer Fabian , Wirth Markus , Lauterbach Maren , Wollenberg Barbara , Schmidl Benedikt , Hoch Cosima C. , Ourailidis Iordanis , Hess Jochen , Eckstein Markus , Hartmann Arndt , Iro Heinrich , Gostian Antoniu-Oreste , Balk Matthias , Jesinghaus Moritz , Ribbat-Idel Julika , Sailer Verena-Wilbeth , Perner Sven , Bruchhage Karl-Ludwig , Hoffmann Markus , Lükewille Lukas , Stuhlmann-Laeisz Christiane Maria , Röcken Christoph , Mogler Carolin , Budczies Jan , Boxberg Melanie
Published: November 2024

Background

We aimed to validate the prognostic significance of tumor budding (TB) in p16-positive oropharyngeal squamous cell carcinomas (OPSCC).

Methods

We analyzed digitized H&E-stained slides from a multicenter cohort of five large university centers consisting of n = 275 cases of p16-positive OPSCC. We evaluated TB along with other histological parameters (morphology, tumor-stroma-ratio, lymphovascular invasion (LVI), perineural invasion) and calculated survival outcomes using both univariate and multivariate analyses.

Results

TB was identified as an independent prognostic parameter, with TB-high cases showing inferior outcomes in univariate (HR: 3.08, 95%-CI: 1.71–5.54) and multivariate analyses (HR: 4.03, 95%-CI: 1.65–9.83). Similarly, LVI remained an independent prognostic factor (HR: 3.00, 95%-CI: 1.22–7.38). A combined classification including TB and LVI stratified cases into low-, intermediate- and high-risk categories. We could not detect correlations between TB and the number of lymph node metastases or between TB and an extracapsular extension of lymph node metastases.

Conclusions

In addition to LVI, we could identify TB as an independent prognostic factor in p16-positive OPSCC in this multicenter study cohort. Thus, evaluating TB along with LVI in a combined scheme for prognostication might help to establish a more personalized treatment regimen for patients with p16-positive OPSCC.
Off-stoichiometry effect on the physical properties of epoxy resins
Authors: Yamamoto Satoru , Phan Nguyen Thao , Kihara Kouki , Shundo Atsuomi , Tanaka Keiji
Published: November 2024

Amines generally tend to segregate at the interface of the epoxy resins cured with amines. To gain better insight into the aggregation states and physical properties at the adhesive interface, we examined the cross-linking structure and physical properties of the cured epoxy resins with an off-stoichiometric ratio of epoxy and amine. As the excess amine increased, the amine not only remained as unreacted monomers or low-molecular-weight isolated chains within the cross-linking structure but also formed dangling chain ends, increasing heterogeneity in the cured epoxy resin. As a result, the cross-linking density and mass density decreased, along with a reduction in the glass transition temperature. On the other hand, Young’s modulus increased with the excess amount of amine. Wide-angle X-ray scattering experiments, in conjunction with molecular dynamics simulations, revealed that the excess amine suppressed the widening of the distance between phenyl groups during the curing reaction, suggesting that this could act as steric resistance during deformation.
Characterizing the evolutionary dynamics of cancer proliferation in single-cell clones with SPRINTER
Authors: Lucas Olivia , Ward Sophia , Zaidi Rija , Bunkum Abigail , Frankell Alexander M. , Moore David A. , Hill Mark S. , Liu Wing Kin , Marinelli Daniele , Lim Emilia L. , Hessey Sonya , Naceur-Lombardelli Cristina , Rowan Andrew , Purewal-Mann Sukhveer Kaur , Zhai Haoran , Dietzen Michelle , Ding Boyue , Royle Gary , Aparicio Samuel ,   TRACERx Consortium,   PEACE Consortium, McGranahan Nicholas , Jamal-Hanjani Mariam , Kanu Nnennaya , Swanton Charles , Zaccaria Simone
Published: November 2024

Proliferation is a key hallmark of cancer, but whether it differs between evolutionarily distinct clones co-existing within a tumor is unknown. We introduce the Single-cell Proliferation Rate Inference in Non-homogeneous Tumors through Evolutionary Routes (SPRINTER) algorithm that uses single-cell whole-genome DNA sequencing data to enable accurate identification and clone assignment of S- and G2-phase cells, as assessed by generating accurate ground truth data. Applied to a newly generated longitudinal, primary-metastasis-matched dataset of 14,994 non-small cell lung cancer cells, SPRINTER revealed widespread clone proliferation heterogeneity, orthogonally supported by Ki-67 staining, nuclei imaging and clinical imaging. We further demonstrated that high-proliferation clones have increased metastatic seeding potential, increased circulating tumor DNA shedding and clone-specific altered replication timing in proliferation- or metastasis-related genes associated with expression changes. Applied to previously generated datasets of 61,914 breast and ovarian cancer cells, SPRINTER revealed increased single-cell rates of different genomic variants and enrichment of proliferation-related gene amplifications in high-proliferation clones.
Evaluation of tumorigenesis-related miRNAs in breast cancer in Egyptian women: a retrospective, exploratory analysis
Authors: Salum Ghada M. , Elaraby Nesma M. , Ahmed Hoda A. , Abd El Meguid Mai , Fotouh Basma E. , Ashraf Muhammed , Elhusseny Yasmine , Dawood Reham M.
Published: November 2024

Breast cancer (BC) is a leading cause of global female cancer-related deaths, despite treatment advancements. A growing focus on investigating microRNA-based therapeutics and their role in BC progression. A computational analysis was performed to identify the potential miRNA–mRNA network involved in the BC pathogenesis and assist with the treatment strategy. Then, the expression levels of five circulatory miRNAs (miR-200a-3p, miR-124-3p, miR-205-5p, miR-15a-5p, and miR-155-5p) were assessed by using qRT-PCR in 75 BC patients (early-stage: n = 26 and late-stage: n = 49) and 20 healthy controls. The analysis included various (a) stages (early and late) and (b) receptor statuses (ER + ve & HER2 -ve), (HER + ve & ER -ve), and triple-negative (TNBC). In-silico analysis suggested that STAT3 serves as an efficacy biomarker suppressed by miR-124-3p. Additionally, the miR-155-5p showed the ability to activate CTNNB1 which acts as a biomarker for BC progression, to inhibit DNA repair genes (ARID2, and WEE1), and the transcriptional factor gene (TCF4). MiR-205-5p and miR-16 suppressed VEGFA expression, a survival factor for BC. MiR-200a-3p, miR-205-5p, and miR-124-3p showed downregulation in the serum of BC patients compared to controls. The ROC analysis of those miRNAs demonstrated their significant diagnostic accuracy for identifying BC patients. Additionally, miR-155-5p exhibited a significant upregulation in TNBC and can be used as an indicative marker for TNBC. This study holds significant promise for the development of noninvasive miRNA biomarkers with potential clinical applications.
The impact of smartphone-dispatched CPR-trained volunteers on OHCA outcomes is influenced by patient age
Authors: Fabianek Johanna , Felzen Marc , Riester Kim R. , Beckers Stefan K. , Rossaint Rolf , Schröder Hanna , Pitsch Mark
Published: November 2024

The early initiation of cardiopulmonary resuscitation (CPR) measures by non-professionals before the arrival of Emergency Medical Service (EMS) is known to be crucial for improving outcomes after out-of-hospital cardiac arrest (OHCA). We assessed the impact of deploying CPR-trained volunteers via a smartphone-based alerting system on the outcome of OHCA patients. In a retrospective nonrandomized cohort study, all OHCA cases in the city of Aachen over a six-year period were analysed. We compared patient data, CPR metrics, alerting system data as well as outcome data between the intervention and control groups. From June 2017 to May 2023, 101 out of 852 resuscitations were initiated by volunteers alerted via a smartphone-based alerting system in OHCA events. We found no overall rise in the return of spontaneous circulation (ROSC) rate. An age-dependent subgroup analysis indicated an increased incidence of initially shockable rhythms and an increased ROSC rate for patients younger than 60 years in the intervention group, while implying a lower ROSC rate in patients older than 80 years after mobile responder CPR. Although this study was underpowered to yield statistically significant results, our findings suggest the need for an age-sensitive approach when evaluating the effects of first-responder systems on OHCA cases.
Construction of a regulable chiral recognition platform based on the photothermal effect of popcorn-like gold nanoparticles/bovine serum albumin
Authors: Wang Yujie , Chen Haibo , Liu Peiming , Cai Wenrong , Wu Datong , Li Junyao , Kong Yong
Published: November 2024

A regulable chiral recognition platform based on the photothermal effect has been developed, which enables efficient discrimination of tyrosine enantiomers.
Plugging synthetic DNA nanoparticles into the central dogma of life
Authors: Neyra Kayla , Desai Sara , Mathur Divita
Published: November 2024

Recent advancements have engineered an approach to encode genetic sequences in DNA nanoparticles, making them a promising platform for gene therapy. This article highlights design considerations of these structures for optimal protein expression.
Efficient pathways to improve electrode performance of P′2 Na2/3MnO2 for sodium batteries
Authors: Ugata Yosuke , Kuriyama Tomohiro , Yabuuchi Naoaki
Published: November 2024

A Mn-based sodium-containing layered oxide, P′2-type Na2/3MnO2, is revisited as a positive electrode material for sodium-ion batteries, and factors affecting its electrochemical performances are examined.
Surface modification unleashes light emitting applications of APbX3 perovskite nanocrystals
Authors: Bhandari Satyapriya , Pramanik Sabyasachi , Manna Mihir , Singha Sumit , Akhtar Farhin
Published: November 2024

This review explores surface modifications of APbX3 perovskite nanocrystals for enhanced optical properties, tackles persistent challenges, and proposes innovative solutions, aiming to revolutionize light-emitting technologies.
Functional coordination compounds for mechanoresponsive polymers
Authors: Gridneva Tatiana , Khusnutdinova Julia R.
Published: November 2024

This review highlights the examples of mechanoresponsive polymers incorporating metal complexes as mechanophores, focusing on different activation pathways upon their mechanoactivation.
Optical properties of [MMim]2[CuI3] crystals with 0D single-core trigonal planar structures
Authors: Han Jiali , Zhu Shujun , Chen Xinxin , Zhou Haichao , Pan Jianguo , Pan Shangke
Published: November 2024

Optical properties of [MMim]2[CuI3] crystals with 0D single-core trigonal planar structures.
Mechanistic insights into CO2 reduction to CO by group 5 transition metal monoxide cations
Authors: Yu Haili , Han Jia , Su Quyan , Liu Pengcheng , Liu Shilin , Zhou Xiaoguo
Published: November 2024

This study investigates the thermodynamics and reaction mechanisms of CO2 reduction by group 5 transition metal monoxide cations.
Controlled encapsulation of colloidal semiconductor quantum dots in a microdroplet
Authors: Biały Maciej , Jankowska Martyna , Sulowska Karolina , Szalkowski Marcin , Niedziółka-Jonsson Joanna , Maćkowski Sebastian
Published: November 2024

Development of reproducible and voltage-less method of precise deposition and controlled degradation-free movement of microdroplets containing a quantified amount of semiconductor quantum dots down to single emitters.
Valley splitting of monolayer Hf3C2O2 by the spin–orbit coupling effect: first principles calculations using the HSE06 methods
Authors: Qiao Shiqian , Zhang Yang , Li Shasha , Wei Lujun , Wu Hong , Li Feng
Published: November 2024

Electrons have not only charge and spin degrees of freedom, but also additional valley degrees of freedom.
Accelerated diradical character assessment in large datasets of polybenzenoid hydrocarbons using xTB fractional occupation
Authors: Wahab Alexandra , Gershoni-Poranne Renana
Published: November 2024

High-throughput calculation of fractional occupation numbers for the entire chemical space of PBHs containing up to 10 rings (19k molecules) reveals that approximately 7% of the molecules are identified as having diradical character.
Unifying thermochemistry concepts in computational heterogeneous catalysis
Authors: Kreitz Bjarne , Gusmão Gabriel S. , Nai Dingqi , Sahoo Sushree Jagriti , Peterson Andrew A. , Bross David H. , Goldsmith C. Franklin , Medford Andrew J.
Published: November 2024

Thermophysical properties of adsorbates and gas-phase species define the free energy landscape of heterogeneously catalyzed processes and are pivotal for an atomistic understanding of the catalyst performance.
Enhancing the reactivity of a P450 decarboxylase with ionic liquids
Authors: Nicholson Jake H. , Chagas de Avila Mayara , Rodrigues de Melo Ricardo , Zanphorlin Leticia Maria , Brogan Alex P. S.
Published: November 2024

This work shows a facile chemical modification strategy for the solubilisation of a P450 decarboxylase in pure ionic liquid, allowing for significant photochemical enhancement of the enzyme activity coupled with substantial process intensification.
Remobilization of ZnO–TA nanoadsorbent for U(vi) and Th(iv) extraction: adsorption optimization through the Box–Behnken design model
Authors: Sharma Manish , Sharma Priya , Taneja Payal , Janu Vikash Chandra , Gupta Ragini
Published: November 2024

The rapid expansion of nuclear technology has led to increasing volumes of radioactive wastewater, threatening the environment and necessitating the removal of contaminants in order to protect the surroundings.
A highly sensitive electrochemical Cd(ii) detector based on an ion-imprinted modified glassy carbon electrode
Authors: Li Wenting , Xu Sheng , Li Zhenghao , Liu Lingli , Wang Zhenxi , Dai Xin
Published: November 2024

A sensitive electrochemical sensor based on ion-imprinted chitosan–graphene (CS/rGO-IIP) nanocomposites has been developed for the determination of Cd(ii).
N-(Trimethylsilyl)diethylamine-Promoted Intramolecular SNAr Reaction of Electron-Rich Aryl Fluorides
Authors: Egi Masahiro , Shigeta Takashi , Ichikawa Yurika , Suzuki Shiho , Hamabe Yui , Nakahara Nanomi , Gonno Yuka , Ozeki Minoru , Kawasaki Ikuo
Published: November 2024

N-(Trimethylsilyl)diethylamine (TMSNEt2) significantly promotes intramolecular nucleophilic aromatic substitution (SNAr) reactions of electron-rich aryl fluorides with t-BuOK and crown ether. Although substrates bearing electron-donating groups are conventionally inert under SNAr conditions, the activation of substrates by TMSNEt2 enables the reactions to proceed even at room temperature. This method is applicable to the preparation of benzo-fused oxygen-containing heterocycles, such as 3,4-dihydro-2H-1,4-benzoxazines, 3,4-dihydro-2H-1,5-benzoxazepines, and 3,4-dihydro-2H-1-benzopyran, in good to excellent yields (56–93%).
Long-Latency Auditory Evoked Potentials in Adults with Williams Syndrome
Authors: Nascimento Jacqueline A. , Silva Liliane A.F. , Samelli Alessandra G. , Matas Carla G.
Published: November 2024

Background Williams syndrome (WS) is a genetic, multisystemic, neurodevelopmental disorder, in which studies have demonstrated the presence of auditory deficits such as conductive and sensorineural hearing loss, cochlear weakness, and subclinical signs of hearing impairment. However, few studies have assessed this population's central auditory system.

Purpose To analyze long-latency auditory evoked potential (LLAEP) in adults with WS and compare them with those obtained from neurotypical individuals with no hearing complaints.

Research Design A cross-sectional observational study with subjects who were submitted to LLAEP assessment with the oddball paradigm and tone-burst stimuli.

Study Sample A total of 30 individuals of both sexes, aged 18 to 37 years—15 had WS and comprised the study group (SG) and 15 did not have either the syndrome or hearing complaints and comprised the control group (CG); they were matched for sex and age.

Results The LLAEP analysis showed larger P1–N1 and P2–N2 amplitudes but smaller N2–P3 amplitude in SG, which also had delayed latencies in all components compared with CG.

Conclusion Adults with WS had increased neuronal response in identifying stimulus characteristics, attentional difficulties in auditory tasks, and deficits in auditory information processing speed.
An Improved Synthesis Process of Ricolinostat: The First Orally Selective HDAC6 Inhibitor
Authors: Wang Mengfei , Sun Niubing , Chen Qiushi , Zhang Qingwei
Published: November 2024

Ricolinostat (1) is the first orally available histone deacetylase 6 inhibitor in phase II clinical trials. The results from phase II clinical studies showed that the combination of Ricolinostat with bortezomib and dexamethasone is safe and active for the treatment of multiple myeloma. However, the reported synthesis routes of Ricolinostat were plagued by several limitations, including severe reaction conditions, elevated cost factors, and the employment of environmentally unfriendly reagents. This study aimed to improve the synthesis process of Ricolinostat, in which ethyl 2-chloropyrimidine-5-carboxylate (2) was used as the starting material, the target product was obtained through the reaction of nucleophilic aromatic substitution, the Ullmann coupling, hydrolyzation amide condensation, and aminolysis. The nucleophilic substitution (2 to 3) was performed in the presence of 1.2 equiv. aniline, 2.0 equiv. K2CO3 under 100°C, with a yield of 96%; the Ullmann reaction was performed in the presence of 0.5 equiv. CuI and 2.0 equiv. cesium carbonate; the post-processes of 3 and the desired product (1) that previously required column chromatography were replaced with recrystallization using the solvent of EtOH/H2O and DMF/H2O, respectively. Through the improved process, Ricolinostat was obtained with an isolated yield of 65.8% and a purity of 99.73%, which was much higher than the reported study. This route was both cost-effective and eco-friendly, making it suitable for industrial applications.
Theory of double Ising chains. Model in an external field
Authors: Yurishchev M. A.
Published: November 2024

An analytic expression is obtained for the free energy of a double Ising chain which is symmetric relative to mutual permutation of the one-dimensional chain components. The behavior of the magnetization and the Stoletov curves is investigated by using an electronic computer. A general classification is given of the kinds of symmetry in the transition matrix space.
Brassinosteroid improves light stress tolerance in tomato (Lycopersicon esculentum) by regulating redox status, photosynthesis and photosystem II
Authors: Yousuf Waseem , Bhat Showkat Ahmad , Bashir Sabeeha , Rather Rayees Ahmad , Panigrahi Kishore Chandra , John Riffat
Published: November 2024

Plants often experience variations in light intensity, referred to as light stress, that negatively impact important aspects of plant growth and development, including photosynthesis and antioxidant system. The photosynthetic machinery is susceptible to these disturbances, especially photosystem II and its reaction centers. We aimed to evaluate the role of brassinosteriod in plants under both high and low light conditions by examining various physiological parameters such as photosynthetic efficiency, pigment levels, and enzymatic activity of various antioxidant enzymes in one month old tomato plants. We investigated various chlorophyll fluorescence parameters under low light (LL) and high light (HL) conditions and the associated gene expression related to photosynthesis, including plastocyanin, ferredoxin, and photosystem II oxygen-evolving enhancer protein 3 (PsbQ). Our results indicate that exogenous brassinosteroid application considerably increased tolerance to both high and low light stress in 4-week-old tomato as treated plants displayed enhanced photosynthesis, reduced oxidative damage, and increased antioxidant enzyme activity in comparison to control plants. Furthermore, brassinosteroid treatment enhanced the expression of genes associated with antioxidant pathways, which significantly contributed to the recovery of chlorophyll fluorescence parameters crucial for plant growth and development. Our results provide valuable insights into how brassinosteroid reduces light-induced stress in tomato plants.
Degenerate lump solutions of the (N+1)-dimensional gKP equation
Authors: Luo Jikang , Zhao Zhen , Pang Jing
Published: November 2024

Using the Hirota bilinear method and the improved long-wave limit method to solve the (N + 1)-dimensional generalized Kadomtsev-Petviashvili (gKP) equation for anomalous scattering and weak interaction solutions. By improving the traditional long-wave limit method, the anomalous scattering of the two lumps are obtained, and the weak interaction solutions of multiple lumps are derived, and the dynamic behavior of the lump solutions are discussed in detail.
Modeling of electromagnetic radiation using a dual four-potential representation: from dipole blade radiators to ribbon loop-like antennas
Authors: Salazar Robert , Bayona-Roa Camilo
Published: November 2024

In this paper, we explore classical electromagnetic radiation using a dual four-dimensional potential Θ
μ
approach. Our focus is on the Planar Dipole Blade Antenna (PDBA), a system consisting of two flat perfect conductive regions on the xy-plane, separated by a gap

G

, with alternating potentials applied to the conductors. This method emphasizes the use of the scalar magnetic potential Ψ(
r
, t) and the electric vector potential
Θ
, which generates the electric field
E
(
r
, t) = ∇ × 
Θ
(
r
, t) in free space. These potentials replace the standard magnetic vector potential
A
and the scalar electric potential
Φ
in our analysis. For harmonic radiation, the electromagnetic field can be expressed in terms of the electric vector potential
Θ
(
r
, t). We derive a corresponding retarded vector potential for
Θ
in terms of a two-dimensional vector field W(
r
, t), which flows through the gap region

G

. This dual analytical approach yields mathematically equivalent expressions for modeling Planar Blade Antennas, analogous to those used for ribbons in the region

G

, simplifying the mathematical problem. In the gapless limit, this approach reduces the two-dimensional radiator (PDBA) to a one-dimensional wire-loop-like antenna, significantly simplifying the problem's dimensionality. This leads to a dual version of Jefimenko's equations for the electric field, where W behaves like a surface current in the gap region and satisfies a continuity condition. To demonstrate the utility of this approach, we provide an analytical solution for a PDBA with a thin annular gap at low frequency.
Improved particle tracking velocimetry based on level set segmentation for measuring the velocity field of granular flow
Authors: Gao 高 Jing-Yi 靖宜 , Chen 陈 Quan 泉 , Li 李 Ran 然 , Sun 孙 Ge 歌 , Mu 牟 Tong-Tong 彤彤 , Yang 杨 Hui 晖
Published: November 2024

Using traditional particle tracking velocimetry based on optical flow for measuring areas with large velocity gradient changes may cause oversmoothing, resulting in significant measurement errors. To address this problem, the traditional particle tracking velocimetry method based on an optical flow was improved. The level set segmentation algorithm was used to obtain the boundary contour of the region with large velocity gradient changes, and the non-uniform flow field was divided into regions according to the boundary contour to obtain sub-regions with uniform velocity distribution. The particle tracking velocimetry method based on optical flow was used to measure the granular flow velocity in each sub-region, thus avoiding the problem of granular flow distribution. The simulation results show that the measurement accuracy of this method is approximately 10% higher than that of traditional methods. The method was applied to a velocity measurement experiment on dense granular flow in silos, and the velocity distribution of the granular flow was obtained, verifying the practicality of the method in granular flow fields.
Proceedings of the 4th European Symposium on Fire Safety Science (ESFSS 2024)
Authors: Planas Eulàlia , Pastor Elsa , Merci Bart
Published: November 2024

EDITORIAL

This special issue is based on the papers selected for presentation during the 4th ESFSS (European Symposium on Fire Safety Science), held in Barcelona, Spain from October 9 to 11, 2024. Following the previous conference held in Nancy in 2018, the European Symposium on Fire Safety Science was the fourth edition in these series of symposia organized in Europe. The aim was to bring together researchers from Europe and beyond for exchanges and discussions on fire safety science.

Approximately 200 contributions were received during the conference preparation, including submissions for both oral and poster presentations. Following a rigorous selection process involving at least 2 peer reviews of the full papers, 45 contributions were accepted for oral presentation and 99 for poster presentation, with 23 of the latter dedicated to work-in-progress.

The conference was attended by 180 scientists from around the world, including countries such as Australia, Belgium, Canada, Chile, China, Czech Republic, Denmark, Finland, France, Germany, Hong Kong, India, Italy, Japan, Republic of Korea, Malaysia, New Zealand, Norway, Poland, Slovenia, South Africa, Spain, Sweden, Switzerland, the United Kingdom, Turkey, and the United States.

This volume includes all the papers from the contributions presented during the seminar. They are organized into six main topics, in line with the conference program:

• Material behaviour in fire (ignition, pyrolysis, flame spread, smouldering)

• Fire dynamics, structures in fire (fire plumes, compartment fires, tunnel fires)

• Wildland fires / Wildland-urban fires

• Fire detection and suppression

• Evacuation and human behaviour

• Miscellaneous (e.g.: explosions and industrial fires, battery fires, solar panels, fire codes and standards)

The conference organizers gratefully acknowledge the members of the scientific committee and the experts who reviewed the papers. They also extend their thanks to ACTIVA Congresos and the local organizing committee for their efforts in preparing the conference. The support from the IAFSS, the sponsors (SODECA; Kingspan. OFR Consultants, FM Global, Efectis and CSTB) the UPC research group CERTEC, and the Universitat Politècnica de Catalunya is also acknowledged.

List of Syposium chairs, Organizing committee, Local organizing committee and Scientific committee are available in this pdf.
Prediction of the time to ignition of wood under transient heat exposure
Authors: Dias Lopes Pauline , Batiot Benjamin , Rogaume Thomas , Dréan Virginie , Guillaume Bruno , Guillaume Eric , Pizzo Yannick , Porterie Bernard
Published: November 2024

The present study improves the modelling of the time of ignition of solid fuels vertically exposed to transient heat flux to be representative of a fire that affects the façade of a building. A comparison between the models of Wang & al. [4], the Flux-Time-Product (FTP) approach [3][6] and new experimental data for the case of wood is presented.

The models consider the effect of the transient radiant exposure, of the moisture content and for the model of Wang & al, the convective effect. Experiments have been carried out for 4 heat flux exposure evolutions expressed as a power-law function of time. The FTP model overestimates the results by at maximum 19% whereas results are overestimated by 31% at least by the model of Wang & al. A correlation has been established in order to determine the parameters n and FTPcr
whatever the value of moisture content.
Experimental investigation on low-cement concrete at elevated temperature with preloaded conditions
Authors: Rokade M , Rush D , Stratford T , Bisby L , Hoult N
Published: November 2024

Concrete is one of the most widely used construction materials globally. Experimental and numerical observations have revealed that failure of concrete structures may occur not only during the heating phase but also during the decay phase of a fire. With the global imperative to reduce CO2 emissions from cement production, traditional concrete is increasingly being replaced with low-cement alternatives. However, there remains a lack of experimental testing regarding the effects of additional supplementary cementitious materials in concrete during and after fire. This paper presents preliminary findings from elevated temperature compressive tests conducted on concrete with three different mixes, two of which involved 40% and 50% cement replacement. The experimental programme indicates that, regardless of the mix type, internal temperatures recorded in the cylinders were minimally affected by differing mix proportions under identical heating scenarios. Additionally, the paper explores the influence of preloading on both the magnitude of peak thermal expansion and the time to reach peak thermal expansion. It is observed that a reduction in cement content results in comparatively more rapid thermal expansion. Furthermore, during the decay phase, the contraction rates are similar regardless of preloading conditions or the reduction of cement content, for identical heating and cooling scenarios.
A method to study ignition of inverted combustible surfaces
Authors: Madden Joshua , Kriel Machelle , Wiesner Felix , Wu Wenxuan , Hilditch Ryan , Ervine Adam , Lange David
Published: November 2024

As timber is combustible, the inherent fuel load of a mass or engineered timber structure can significantly impact compartment fire dynamics compared to a non-combustible structure. Recently, large-scale open-plan testing reaffirmed these phenomena in compartments with exposed timber, with a rapid transition to fully developed fire following the ignition of the exposed timber ceiling. However, no standardised approaches have been developed to investigate this phenomenon at a bench-scale inverted (i.e. downward-facing) orientation. A method to study the ignition of inverted combustible surfaces is proposed whereby the Fire Propagation Apparatus (FPA) is modified to permit testing at this inverted orientation. Results for this comparative piloted ignition study for a conventional horizontal orientation and an inverted orientation indicate proof of the applicability of the methodology whereby the times to ignition of Cross-Laminated Timber (CLT) were higher for the inverted orientation, compared to a horizontal orientation, demonstrating the suitability of the methodology.
Characterization of the combustion products of fluorinated compounds
Authors: Murillo Rueda Carlos , Attif Salma , Bertrand Jean-Pierre , Leroy Guillaume , Tribouilloy Benoit , Marlair Guy , Gentilhomme Olivier
Published: November 2024

An experimental study is performed to characterize the halogenated gases produced by the combustion of five fluorinated liquid compounds. For this purpose, a FPA calorimeter is coupled with a FTIR spectrometer for the gas analysis. The characterization compares different ignition sources (horizontal and vertical injection to an acetone pool fire and pilot flame) by assessing the emission factors of HF, COF2 and the unreacted compound. The experimental data allowed establishing that the pilot flame mainly generates an insufficient decomposition of the compound due to an excessive evaporation rate. On the contrary, the ignition through the pool fire promotes the conversion of the fluorinated compound due to greater interactions with combustion radicals. These interactions are affected by the position of the injection and might induce significant variations on the selectivity of the decomposition reactions.
The effect of water content on the fire resistance of silica fume-based geopolymers for the protection of steel structures
Authors: Yang Qi , Davy Catherine A. , Sarazin Johan , Bourbigot Serge , Fontaine Gaëlle
Published: November 2024

Intumescent coatings have the ability to expand during fire and thus provide a significant thermal barrier. They are an asset for the fire protection of steel building structures. In this context, different formulations of intumescent geopolymers (GP) have been proposed in former research. However, the influence of the water content on the fire resistance of GP coated on steel is not well known. This justifies the present study. In the following, GP samples with different water contents are tested and compared using a burn through test set-up, under both undried and dried conditions. Post-mortem analysis via 29Si solid-state NMR indicates that a higher initial water content leads to a greater degree of geopolymerization. However, this factor does not significantly impact the fire protection of the GP. Conversely, the drying process results in a deterioration of the GP fire performance during the early stages of the fire test, compared to undried samples. Nevertheless, after 30 minutes, by the end of the fire test, the GP temperature becomes stable and no significant difference is observed between dried/undried GP. GP is able to provide the same level of fire protection, even if exposed to a drying environment.
Electrical insulation performance of flame-retardant electrical cables with thermoplastic and thermosetting materials for nuclear power plants
Authors: Takizawa M , Kabashima H , Matsuda A
Published: November 2024

Fire accidents are a significant evaluation target for the safety management of nuclear power plants (NPPs). During fire accidents, the combustion of electrical cables and electrical failure due to thermal damage have the potential to occur. In NPPs, thermoplastic (TP) cables, thermosetting (TS) cables and TP/TS hybrid cables are used. However, the electrical insulation performance of TP/TS hybrid cables at increased temperatures are not fully understood especially for flame-retardant cables. To improve the knowledge of the electrical insulation performance of hybrid cables and TS cables in fires, the authors analyzed the thermal degradation tests of flame-retardant cables (TP/TS hybrid cable and TS cable) recently conducted at University of Tsukuba. The tests were conducted using modified cone calorimeter to evaluate the electrical insulation performance of cables for the temperature range to about 560°C. As a result, information about decrease in the insulation resistance with the temperature of the cables were obtained. The insulation resistance reached lower measurement limit of the super insulation meter at cable surface temperatures above 400°C. Such insulation performance changes were common in both the hybrid and TS cables and similar to those obtained by a comparable previous study with different insulation materials.
Improving cable tray fire modelling with AI techniques
Authors: Plumecocq W , Prétrel H , Joret J P , Chojnacki E
Published: November 2024

Modelling cable tray fires remains a complex issue, and existing models such as the FLASH-CAT model still have limitations due to the lack of information on certain input data. This paper discusses improvements in cable tray fire modelling by finding appropriate input data using an artificial intelligence (AI) technique. An AI-driven expert system was developed to assess missing data from a fire test database of 29 large scale cable tray fire experiments in open atmosphere. The expert system quantifies the dependencies between input and output data, helps identify influential parameters and refine model inputs. It also guides modelling efforts by identifying areas for model improvement. In this way, the applicability of an expert system in obtaining reliable input data for simulation tools to simulate a real fire scenario that has already been tested is demonstrated. Cable tray fire simulation results show improved accuracy compared with the use of default values for uncertain parameters.
Char depth of several wood species under single or double heat exposures
Authors: Terrei Lucas , Erez Giacomo , Aguilar Boris , Acem Zoubir , Suzanne Mathieu , Reszka Pedro , Boulet Pascal , Parent Gilles
Published: November 2024

For many engineering and fire investigation applications, understanding the behaviour of materials exposed to fire often relies on fairly simple measurements (e.g. char thickness) to deduce the quantities of interest (e.g. fire size or duration) by trying to account for a number of complex phenomena (e.g. influence of wood species, dimensions or moisture content). The aim of the work presented here is to analyse the charring process as a function of different experimental parameters, mainly a varying heat flux. The robustness lies in the large number of cone calorimeter experiments, as the char characteristics of 783 samples were measured. The results show promising correlations between the char depth (combination of missing and remaining char thicknesses) and the cumulative exposure, which represents the energy received by the sample, for a single or a double exposure and independently of the other experimental conditions.
Combustion and free burning behaviour of recycled plastic pellets
Authors: Devine C , Flores-Quiroz N , Walls R
Published: November 2024

This paper details the behaviour of plastic pellets under various fire conditions. Plastic pellets made of recycled plastic materials namely, low density polyethylene (LDPE), high density polyethylene (HDPE) and polypropylene (PP) are the subject of this paper. Recycled plastic has contaminants not present in virgin plastic, and the geometry has been adjusted, whereby the latter has a significant impact on fire phenomena. Cone calorimeter tests were conducted at 25, 35 and 50 kW/m2. At 35 kW/m2the average heat of combustion (HOC), average time to ignition (TTI) and average heat release rate (HRR) over all three materials tested are 44 MJ/kg, 39 s, and 560 kW/m2 respectively. Behaviour observed during experiments is described based on the cone calorimeter tests as well as non-standardised free burn tests – for illustrative purposes. These observations include ease of ignition and initial flames spread, mass involved in burning, burning in layers, formation of solidified layers and whether the material will remain burning after the removal of the external heat source. During combustion the material flows, potentially leading to flaming pools, but would also solidify during the application of water making suppression of deep-seated fires difficult. Although recycled plastic pellets are difficult to ignite, once ignited they burn intensely making them a much larger fire risk than an ignition risk. Early detection of such fire is imperative for fire extinguishment.
Ignition and burning characterization of edible oils
Authors: Alonso Alain , Lázaro Mariano , Rueda Cristina , Placer Emilio , Alvear Daniel
Published: November 2024

Regardless of the country or geographical area, kitchens are the rooms where fires are most likely to begin in homes, and cooking is the leading cause. Statistics consistently demonstrate that cooking fires primarily occur due to the ignition of cooking materials. Consequently, understanding the thermal properties and combustion behaviour of edible oils is crucial for developing effective fire prevention, detection and suppression strategies. In this work, three oils (soybean, rapeseed, and sunflower) are analysed, namely, their behaviour at high temperatures by identifying parameters such as the time to ignition, critical heat flux, thermal response parameter, and effective heat of combustion. The results obtained showed that edible oils required a high temperature to reach ignition, however, once reached the energy released was similar to other liquid fuels employed for combustion purposes.
Impact of fuel bed permeability on feasibility of fire detection in waste and recycling materials
Authors: Grainger Amy , Sangster Angus , Ndlovu Shephard , Liyanage Champika , Williams Karl , Asimakopoulou Eleni , Graham Tony
Published: November 2024

Waste fire testing of deep-seated fires in a variety of materials identified that waste material fuel beds may be categorised by the permeability of the fuel bed with regards to the products of combustion including heat and flames. Current works experimental measurements showed that permeable fuel beds allow for the passage of heat through the fuel bed while impermeable fuel beds hinder the movement of a fire and of fire products. It is proposed, based on the observed differences in heat spread through and to the exterior of an impermeable versus a permeable fuel bed, that typical fire detection methods are less effective on impermeable fuel beds.
Radiative heat transfer methodologies from compartment fires to adjacent walls: A Numerical Investigation
Authors: Cameron Angus , Asimakopoulou Eleni
Published: November 2024

In a fire scenario, the externally ventilating flames (EVF) often project beyond the compartment of fire origin and in some cases boundary distances, increasing the likelihood of fire spread between buildings. This work investigates various numerical methodologies to predict radiative heat transfer from compartment fires to adjacent walls at different orientations (20, 40, 60 and 80 degrees). Predictions were compared to empirically derived equations. Results show that code compliant scenarios may still exceed critical heat flux recommendations. Furthermore, the effects of prolonged heat exposure and materials should be considered by designers.
Tray configuration factors on cable flame spread
Authors: Lázaro David , Lázaro Pedro G. , Lázaro Mariano , Ángel Jiménez Miguel , Alvear Daniel
Published: November 2024

Fire propagation in cable trays is a critical concern in the design and safety of nuclear power plants (NPP), as it can facilitate the spread of fire between different enclosures or affect cables necessary to a safety shutdown procedure. While international programs such as CHRISTIFIRE and PRISME have contributed to our understanding through various experimental campaigns, the complexity of the phenomena and the multitude of boundary conditions affecting cable tray scenarios necessitate further experimental analysis. The objective of the study was to provide insights into the configuration factors influencing fire spread in cable trays. Through a series of controlled laboratory experiments, a set of cable tray configurations were analysed. Our results revealed critical issues influencing fire propagation and indicated like the number of cables per trays and the number of trays.
Can flame-retardant sheath protect flammable insulation?
Authors: Gholami Haghighi Fard Morteza , Hostikka Simo
Published: November 2024

Electrical cable fires are significant hazards, prompting recent efforts to reduce cable flammability by blending halogen-free flame-retardant materials with the base polymer; however, combining flame-retardant sheaths with non-flame-retardant insulations is a common practice in the cable industry. Sheath breakage, and in turn, exposure of the non-flame-retardant insulation to the external heat source is a severe fire risk that can be observed both in vertical flame spread standard tests, like EN 60332 and UL 1581, and laboratory scale measurements, such as cone calorimetry measurements.

To further understand details of the physics involved in causing such fire hazard, the current study compares the fire characteristics of two cables: One cable (MKEM-HF) comprising a flame-retardant sheath (ATH+base polymer) and conductor, and another cable (XMK-HF) consisting of a flame-retardant sheath (MDH+base polymer), non-flame-retardant insulation (XLPE), and conductor, analyzed via TGA, DSC, and cone calorimetry. TGA and DSC analyses of the sheaths identified that the ATH degrades at lower temperatures in MKEM-HF, while MDH pyrolysis was near the main polymer’s pyrolysis temperature in XMK-HF. Cone calorimetry tests at 50 kW • m−2 assessed cable flammability, revealing MKEM-HF’s descending fire risk pattern and XMK-HF’s continuous ascending HRR trend leading to a notable final HRR peak. The latter was mainly caused by the sheath’s mechanical breakage over time, exposing XLPE insulation, and thus accelerating material decomposition.
Fire Performance of a Wooden Façade System Based on the Draft European Test Method: Assessing the Contribution from the Side Wing
Authors: Zhao G , Dragsted A , Frederiksen M F , Haastrup A , Schou C F , Livkiss K
Published: November 2024

This study presents the results of large-scale fire tests conducted on a ventilated wooden façade system, based on the draft European testing method to assess the fire performance of the façade systems in cases with and without combustible material on the side wing. Spruce has been used as cladding material. Two distinct tests were conducted to evaluate the effect of adding combustible material to the side wing on the fire performance of the façade system. Test results indicated a significant difference in fire behaviour with the addition of combustible materials on the side wing. In the test without combustible material on the side wing, flame spread was confined to the first floor. In contrast, test with wood panels on the side wing, exhibited more severe burning and damage, with flames spreading to the base of the second floor. Heat flux and temperature measurements highlighted the increased fire intensity and spread due to the combustible side wing. The findings emphasize the critical role of façade configurations in building’s fire safety design.