bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the effects of microstructures on the fracture behavior of an Al-Cu-Mg alloy
Authors: Liu Qilong , Li Xiwu , Li Zhihui , Wang Fengchun , Fu Jinlai , Gao Guanjun
Published: August 2023

In this study, a special fracture delamination in L-T fracture toughness specimens of an Al-Cu-Mg alloy was researched by applying three-dimensional optical microscopy (OM), scanning electron microscopy (SEM), and electron backscatter diffraction (EBSD) methods. The results indicate that the fracture delamination is contributed by the cracks extending a long distance in the T-direction and extending internally along the L-direction, which can result in a lower fracture toughness value. The fracture delamination is determined by the level of grain flattening and the distribution of the second phases. The flat grains result in a tendency for cracks to extend in the T-direction. At the same time, the unevenly distributed Al2Cu and Al2CuMg phases lead to cracks extending in the L-direction, which eventually causes the formation of delamination fractures. The reduction in grain size can also contribute to weakening the fracture delamination to a certain extent.
Study on Microstructural Evolution and Mechanical Behavior of Cold Rolled 316L Stainless Steel during Isothermal Annealing
Authors: Zhao Miaomiao , Liu Yang , Du Linxiu
Published: August 2023

316L stainless steel (SS) was processed using cold rolling and annealing to study microstructural evolution and mechanical behavior. The findings revealed that the deformation mechanism of 316L SS was dominated by deformation twinning during the cold rolling process. Different initial microstructures were prepared by annealing at 750 °C for 5 to 60 min. Various yield strengths (545–1192 MPa) and ductility (7.61–37.61%) combos were obtained according to grain size and annealing circumstances.
Research on 40Cr Laser Quenching Process for Guide Rail
Authors: Wu Lifeng , Long Weiming , Hao Qinle , Cheng Zhan , Yang Yang , Shi Lubing , Wu Yuanke
Published: August 2023

In this study, the use of laser quenching was explored as a method of surface strengthening for 40Cr steel utilized in machine tool guideways. The impact of various process parameters, including laser power, scanning speed, and spot radius, on the hardness and depth of the quenched layer was evaluated. The results indicated that the optimal process parameters were a laser power of 2000 W, a scanning speed of 20 mm/s, and a spot radius of 3 mm, which resulted in a maximum quenched layer hardness of 889 HV, an average quenched layer hardness of 764 HV, and a quenched layer depth of 0.7 mm. The application of the laser quenching process through multiple passes was shown to further improve the material properties, resulting in a hardness increase from 749 HV in a single quench to 980 HV in 16 quenches and a corresponding increase in the quenched layer depth from 0.2 mm to 0.9 mm. The hardness of the surface treated by the lap quenching process increased from 250 HV after a single quench to 390 HV after repeated quenching, leading to a more uniform distribution of hardness on the material surface. Furthermore, the average coefficient of friction decreased from 0.67 to 0.37, and the weight loss due to wearing was reduced from 9.7 mg to 1.7 mg after the staggered repeated quenching process.
Modulation of Optical Behavior in MoS2/WS2 Heterobilayers Using Hydrostatic Pressure
Authors: Li Yao , Song Zongpeng
Published: August 2023

The two-dimensional van der Waals (vdW) heterostructure composed of transition metal dichalcogenides (TMDs) has great photoelectric properties because of different energy band arrangements and interactions between layers. The lattice structure and photophysical properties of TMDs can be regulated through pressure, thus altering the properties of interlayer excitons. This study’s chemical vapor deposition method grew MoS2/WS2 vertical heterostructure. Its vibration mode signal and interactions between layers under pressure were investigated by pressure-variable Raman and photoluminescence (PL) spectra. We found that an inflection point appears at 1.22 GPa-1.89 GPa, and the PL peak changed with the variation trend of pressure. It is believed that the energy band transformation of MoS2/WS2 vertical heterostructures is induced by pressure. Our findings provide valuable information which is conducive to the development of new functional optoelectronic devices.
Study on the Strengthening Effect of Interlayer Micro-rolling on Additively Manufactured Al–4.7Si Alloy
Authors: Huang Jianwu , Wang Ruizhe , Zhang Haiou , Wang Guilan
Published: August 2023

Al-Si alloy is one of the most important and commonly used materials in the manufacture of lightweight components for automobiles. However, Its application is limited by low-strength properties, which are usually caused by micropores and columnar grains of the as-deposited WAAM alloy. To effectively address these issues, a special method of inter-layer micro rolling was used to fabricate the additively manufactured Al–4.7Si alloy in this paper. The strengthening mechanism of micro-rolling on this alloy was systematically studied by analyzing microstructure and properties. The experimental results showed that the number of micropores was substantially reduced, and the growth of columnar grains was significantly interrupted by inter-layer micro rolling, which had a clear effect on improving the mechanical properties of 4043 Al-Si alloy. The average ultimate tensile strength (UTS) and yield strength (YS) of the micro-rolled sample with 4 kN load achieved 159 MPa and 72 MPa, respectively, which were 18.6% and 38.5% higher than that without rolling, and elongation (EL) increased from 12.3% to 16.2%. This study is expected to provide an experimental and theoretical basis for improving the mechanical properties of additively manufactured aluminum alloys.
Design and Verification of Complex Intelligent Integrated Dual-robot Collaborative Drilling and Riveting System for Aircraft Assembly
Authors: Gao Wenxiang , Wei Haojie , Luo Yun , Lu Dawei , Zhang Lixin , Liu Chun , Wang Jiaxin
Published: August 2023

A complex intelligent integrated dual-robot collaborative drilling and riveting aircraft assembly system is proposed in this paper to solve the application problem of automatic drilling and riveting in narrow spaces. Firstly, the structure of the system is described. Then, the multifunctional end effectors which include intelligent drilling and riveting units are designed. Finally, relevant experiments are designed to verify the application of the system for the automatic drilling and riveting of complex laminated materials in different aircraft. The results show that the system can well adapt to the application scenarios of aircraft automatic drilling and riveting.
Simulation and Analysis of Welding Spot Failure of PCB Based on ABAQUS
Authors: Ma Zhuqiao , Tong Yifei , Liu Linyan , Huang Lei , Yuan Juntang
Published: August 2023

In the manufacturing process, the welding spot of PCB may lose efficacy because of the strain and stress impact. The reason for the occurrence of high-stress zones is the effect of the load brought by the manufacturing and assembly process. It is a giant challenge for the industry community to solve the problem of welding spots losing efficacy.

In this paper, the manufacturing techniques and assembly process will be analyzed first. With the analysis result, the main impact of load would be checked. Then, with the confirmed allowable stress by calculation, the value of input stress, which may cause the welding spot to lose efficacy, would be obtained. Finally, the result of this study would be confirmed by the simulation result generated by the finite element analysis software.
Ti3C2TX MXene@rGo Composite self-supporting membrane and its welding process
Authors: Ding Mingli , Zhang Xinyue , Zhang Wu
Published: August 2023

Ti3C2Tx MXene@rGo self-supporting film was prepared by HF etching and LiF/HCl etching method, and film welding was realized for the first time. The results showed that Ti3C2Tx MXene with typical accordion-like morphology was obtained by HF etching. In the Ti3C2Tx MXene@rGo self-supporting film welding test, it was found that in the time-sensitive period, Ti3C2Tx MXene@rGo self-supporting film can be welded with water as the medium, effectively ensuring the stability of the material welding. If beyond the time-sensitive period, the self-supporting film will lose weldability. This study is a significant advancement for the large-scale Ti3C2Tx MXene@rGo composites.
Study on the Effect of Pre-strain on Fatigue Properties of Dual-phase Steel
Authors: Li Yan , Xia Lei , Wang Keqiang , Su Hongying , Wang Xiaohang , Li Qihang , Wang Qing
Published: August 2023

The uniaxial tensile test investigated the fatigue performance of DP780 steel without pre-strain and with 5% and 10% uniaxial pre-strain. Topography of fractured surfaces was observed to study the relationship between pre-strain and fatigue performance. The results showed that pre-strain the specimens would affect the fatigue performance of DP780 steel. It would cause an increase in fatigue life when the stress was comparatively high and the fatigue life was less than 100,000 cycles. However, the fatigue life was reduced when the stress level was comparatively low, and the fatigue life was more than 100,000 cycles. Pre-strain reduced the fatigue strength of samples. Fatigue strength of specimens without pre-strain and 5% and 10% pre-strain were 318 MPa, 310 MPa, and 303 MPa, respectively. The sample fracture was a brittle fracture with a pre-strain of 5%, while it was a ductile fracture with a pre-strain of 10%.
Optimization of CF/PEKK molding process by orthogonal experiment
Authors: Cheng Zhitong , Qi Junwei , Wang Yuequan , Jin Jianghai
Published: August 2023

Composite materials have gradually entered people’s attention due to their advantages such as lightweight, high strength, corrosion resistance, fatigue resistance, and strong designability. Widely used in aviation, aerospace, automotive and other fields.[1-4].. The basic mechanical properties of the laminates were evaluated through short beam shear and bending tests. The optimum forming process was determined by orthogonal test: forming temperature 380°C, forming pressure 2 MPa, holding time 60 min, cooling rate 2°C/min. The interlaminar shear strength of this process was 103.42 MPa, and the bending strength was 1570 MPa
Research on Optimization Method of Configuration Number of Automatic Guided Vehicles and Transportation Sequence of Workpieces in Workshop
Authors: Xu Liyun , Ariel M.F Jonathan William , Zhou Zhuo , Qin Haoran
Published: August 2023

The number of automatic guided vehicles (AGVs) and the sequence of workpieces transported from the warehouse affect the final processing completion time of the system. Therefore, this paper researches the optimal configuration number of AGVs and sequence of transport workpieces in the workshop. Firstly, an optimization model is built with minimizing completion time. Secondly, Plant Simulation is used to determine the optimal configuration number of AGVs. Thirdly, linear sequence and uniform crossover, inversion, and exchange mutation are used to generate a new generation of populations, and a genetic algorithm (GA) is improved to optimize the transportation sequence of workpieces. Finally, an example verifies the effectiveness of the proposed method.
Constant Control of Tension Force Based on Fuzzy Proportion Integral Differential Algorithm
Authors: Wang TianXu
Published: August 2023

To overcome the problem that the tension of a diamond wire saw wire affects the surface quality of slices, the constant tension control of diamond wire saw wire is studied by using the Matlab software, and the wire saw tension is controlled by fuzzy PID (Proportion Integral Differential) algorithm and compared with classical PID control algorithm. The simulation data is obtained to verify the reliability and superiority of the fuzzy PID control algorithm.
Memory Performance Enhancement by Inducing Conductive Channel via Doping
Authors: He Hongyang , Li Tiejun , Lin Yuxiang , Yang Shuya , Li Maojing , Pan Jinyan
Published: August 2023

Due to the excellent nonvolatile resistance characteristics demonstrated by hafnium oxide, it is the potential to facilitate the use of resistive random access memory. In this paper, an ingenious method using doping to locate conductive channels is presented to improve the stable rheostatic performance of HfO2-based rheostatic memory. Metal particles are located to enhance the electric field locally to spur on conductive filaments in situ so that the resistive parameters Vset and Vreset are reduced, the relative fluctuation value (standard deviation/mean) of the Vset is reduced from 22.57% to 18.16%, and that of Vreset is reduced from 19.59% to 16.77%. Consequently, the device gains more stable resistance switching with a larger resistive window.
DIMUS: super-compact Dimuonium Spectroscopy collider at Fermilab
Authors: Fox Patrick J. , Jindariani Sergo , Shiltsev Vladimir
Published: August 2023

While dimuonium (μ
+
μ
-) — the “smallest QED atom”
— has not yet been observed, it is of utmost fundamental interest.
By virtue of the larger mass, dimuonium has greater sensitivity to
beyond the standard model (BSM) effects than its cousins positronium
or muonium, both discovered long ago, while not suffering from large
QCD uncertainties. Dimuonium atoms can be created in e
+
e
- 
collisions with large longitudinal momentum, allowing them to decay
a small distance away from the beam crossing point and avoid prompt
backgrounds. We envision a unique cost-effective and fast-timeline
opportunity for copious production of (μ
+
μ
-) atoms at the
production threshold via a modest modification of existing Fermilab
Accelerator Science and Technology (FAST) facility to arrange
collisions of 408 MeV electrons and positrons at a 75° 
angle. This compact 23 m circumference collider (DIMUS) will allow
for precision tests of QED and open the door for searches for new
physics coupled to the muon. The FAST facility is perfectly suited
for DIMUS as there are existing SRF accelerators and infrastructure,
capable of producing high energy, high current electron and positron
beams, sufficient for O(1032)cm2 s-1 
luminosity and ∼0.5 million dimuons per year. The expansion
will require installation of a second SRF cryomodule, positron
production and accumulation system, fast injection/extraction
kickers and two small circumference intersecting rings. An
approximately meter-sized detector with several layers of modern
pixelated silicon detector and crystal-based electromagnetic
calorimeters will ensure observation of the decays of dimuonium to
electron-positron pairs in presence of the Bhabba scattering
background. An expansion of the system to include solenoidal magnet
outside of the calorimeter system, a layer of steel shielding behind
the magnet, and a set of dedicated muon detectors would extend the
physics program of DIMUS to include precision studies of rare
processes with muons, pions, and η mesons produced in
 e
+
e
- collisions.
Triaxial bioprinting large-size vascularized constructs with nutrient channels
Authors: Zhang Junbiao , Suttapreyasri Srisurang , Leethanakul Chidchanok , Samruajbenjakun Bancha
Published: August 2023

Bioprinting has demonstrated great advantages in tissue and organ regeneration. However, constructing large-scale tissue and organs in vitro is still a huge challenge due to the lack of some strategies for loading multiple types of cells precisely while maintaining nutrient channels. Here, a new 3D bioprinting strategy was proposed to construct large-scale vascularized tissue. A mixture of gelatin methacrylate (GelMA) and sodium alginate (Alg) was used as a bioink, serving as the outer and middle layers of a single filament in the triaxial printing process, and loaded with human bone marrow mesenchymal stem cells and human umbilical vein endothelial cells, respectively, while a calcium chloride (CaCl2) solution was used as the inner layer. The CaCl2 solution crosslinked with the middle layer bioink during the printing process to form and maintain hollow nutrient channels, then a stable large-scale construct was obtained through photopolymerization and ion crosslinking after printing. The feasibility of this strategy was verified by investigating the properties of the bioink and construct, and the biological performance of the vascularized construct. The results showed that a mixture of 5% (w/v) GelMA and 1% (w/v) Alg bioink could be printed at room temperature with good printability and perfusion capacity. Then, the construct with and without channels was fabricated and characterized, and the results revealed that the construct with channels had a similar degradation profile to that without channels, but lower compressive modulus and higher swelling rate. Biological investigation showed that the construct with channels was more favorable for cell survival, proliferation, diffusion, migration, and vascular network formation. In summary, it was demonstrated that constructing large-scale vascularized tissue by triaxial printing that can precisely encapsulate multiple types of cells and form nutrient channels simultaneously was feasible, and this technology could be used to prepare large-scale vascularized constructs.
Human adipose-derived mesenchymal stem cells laden in gellan gum spongy-like hydrogels for volumetric muscle loss treatment
Authors: Alheib Omar , da Silva Lucilia P , Mesquita Katia A , da Silva Morais Alain , Pirraco Rogério P , Reis Rui L , Correlo Vitor M
Published: August 2023

Background: volumetric muscle loss (VML) is a traumatic massive loss of muscular tissue which frequently leads to amputation, limb loss, or lifetime disability. The current medical intervention is limited to autologous tissue transfer, which usually leads to non-functional tissue recovery. Tissue engineering holds a huge promise for functional recovery. Methods: in this work, we evaluated the potential of human adipose-derived mesenchymal stem cells (hASCs) pre-cultured in gellan gum based spongy-like hydrogels (SLHs). Results: in vitro, hASCs were spreading, proliferating, and releasing growth factors and cytokines (i.e. fibroblast growth factor, hepatocyte growth factor, insulin-like growth factor 1, interleukin-6 (IL-6), IL-8, IL-10, vascular endothelial growth factor) important for muscular regeneration. After implantation into a volumetric muscle loss (VML) mouse model, implants were degrading overtime, entirely integrating into the host between 4 and 8 weeks. In both SLH and SLH + hASCs defects, infiltrated cells were observed inside constructs associated with matrix deposition. Also, minimal collagen deposition was marginally observed around the constructs along both time-points. Neovascularization (CD31+ vessels) and neoinnervation (β-III tubulin+ bundles) were significantly detected in the SLH + hASCs group, in relation to the SHAM (empty lesion). A higher density of α-SA+ and MYH7+ cells were found in the injury site among all different experimental groups, at both time-points, in relation to the SHAM. The levels of α-SA, MyoD1, and myosin heavy chain proteins were moderately increased in the SLH + hASCs group after 4 weeks, and in the hASCs group after 8 weeks, in relation to the SHAM. Conclusions: taken together, defects treated with hASCs-laden SLH promoted angiogenesis, neoinnervation, and the expression of myogenic proteins.
CNT incorporation improves the resolution and stability of porous 3D printed PLGA/HA/CNT scaffolds for bone regeneration
Authors: Kaya Hatice , Arıcı Şule , Bulut Osman , Bilgili Fuat , Ege Duygu
Published: August 2023

In this study, 3D printed porous poly(lactide-co-glycolide) (PLGA) and its nanocomposites with 5 wt. % hydroxyapatite (HA) and 0.5, 1 and 2 wt. % carboxyl-functionalized multi-walled carbon nanotube (CNT) scaffolds were fabricated by using extrusion-based printing. The printing parameters were optimized by rheological studies. The rheological studies demonstrated shear thinning properties for all compositions and an increase in storage modulus was observed after the addition of CNT. Porous PLGA/HA/CNT scaffolds were printed by applying a pressure of 4.76 bar at 125 °C. The addition of 0.5 wt. % of CNT reduced the strut size and increased the porosity from 42% to 60%. The increase in storage modulus and decrease in strut size were related to hydrogen bonding between CNT, HA and PLGA which ultimately improved shape fidelity. The scaffolds were characterized by analysis of their chemical structure, water contact angle measurement, in vitro bioactivity test, biodegradation test, mechanical analysis, and in vitro cell studies. The scaffolds were found to be more hydrophilic by the incorporation of CNTs. Also, degradation studies showed that the microstructure of the scaffold became more stable with the addition of HA and CNT. The compressive modulus of PLGA/HA/CNT2 scaffold was found to be 548.5 MPa, which is found suitable to replace cancellous bone. The scaffolds were found to be highly biocompatible which is possibly due to alignment of CNT and PLGA during 3D printing process. Alizarin red staining indicated improvement of mineralization of MC3T3-E1 cells on the CNT incorporated porous 3D scaffolds. The results suggest that the produced porous 3D printed PLGA/HA/CNT scaffolds are promising for bone regeneration applications.
Quantum integrability vs experiments: correlation functions and dynamical structure factors
Authors: Lencsés M , Mussardo G , Takács G
Published: August 2023

Integrable Quantum Field Theories can be solved exactly using bootstrap techniques based on their elastic and factorisable S-matrix. While knowledge of the scattering amplitudes reveals the exact spectrum of particles and their on-shell dynamics, the expression of the matrix elements of the various operators allows the reconstruction of off-shell quantities such as two-point correlation functions with a high level of precision. In this review, we summarise results relevant to the contact point between theory and experiment providing a number of quantities that can be computed theoretically with great accuracy. We concentrate on universal amplitude ratios which can be determined from the measurement of generalised susceptibilities, and dynamical structure factors, which can be accessed experimentally e.g. via inelastic neutron scattering or nuclear magnetic resonance. Besides an overview of the subject and a summary of recent advances, we also present new results regarding generalised susceptibilities in the tricritical Ising universality class.
Increased breath naphthalene in children with asthma and wheeze of the All Age Asthma Cohort (ALLIANCE)
Authors: Shahrokny P , Maison N , Riemann L , Ehrmann M , DeLuca D , Schuchardt S , Thiele D , Weckmann M , Dittrich A M , Schaub B , Brinkmann F , Hansen G , Kopp M V , von Mutius E , Rabe K F , Bahmer T , Hohlfeld J M , Grychtol R , Holz O ,   The ALLIANCE Study Group
Published: August 2023

Exhaled breath contains numerous volatile organic compounds (VOCs) known to be related to lung disease like asthma. Its collection is non-invasive, simple to perform and therefore an attractive method for the use even in young children. We analysed breath in children of the multicenter All Age Asthma Cohort (ALLIANCE) to evaluate if ‘breathomics’ have the potential to phenotype patients with asthma and wheeze, and to identify extrinsic risk factors for underlying disease mechanisms. A breath sample was collected from 142 children (asthma: 51, pre-school wheezers: 55, healthy controls: 36) and analysed using gas chromatography–mass spectrometry (GC/MS). Children were diagnosed according to Global Initiative for Asthma guidelines and comprehensively examined each year over up to seven years. Forty children repeated the breath collection after 24 or 48 months. Most breath VOCs differing between groups reflect the exposome of the children. We observed lower levels of lifestyle-related VOCs and higher levels of the environmental pollutants, especially naphthalene, in children with asthma or wheeze. Naphthalene was also higher in symptomatic patients and in wheezers with recent inhaled corticosteroid use. No relationships with lung function or TH2 inflammation were detected. Increased levels of naphthalene in asthmatics and wheezers and the relationship to disease severity could indicate a role of environmental or indoor air pollution for the development or progress of asthma. Breath VOCs might help to elucidate the role of the exposome for the development of asthma. The study was registered at ClinicalTrials.gov (NCT02496468).
Dual-band electro-optically steerable antenna
Authors: Vovchuk Dmytro , Mikhailovskaya Anna , Dobrykh Dmitry , Salgals Toms , Ginzburg Pavel
Published: August 2023

The ability to obtain dynamic control over an antenna radiation pattern is one of the main functions, desired in a vast range of applications, including wireless communications, radars, and many others. Widely used approaches include mechanical scanning with antenna apertures and phase switching in arrays. Both of those realizations have severe limitations, related to scanning speeds and implementation costs. Here we demonstrate a solution, where the antenna pattern is switched with optical signals. The system encompasses an active element, surrounded by a set of cylindrically arranged passive dipolar directors, functionalized with tunable impedances. The control circuit is realized as a bipolar transistor, driven by a photodiode. Light illumination in this case serves as a trigger, capable of either closing or opening the transistor, switching the impedance between two values. Following this approach, a compact half-a-wavelength footprint antenna, capable of switching between 6 dBi directional patterns within a few milliseconds’ latency was demonstrated. The developed light activation approach allows constructing devices with multiple almost non-interacting degrees of freedom, as a branched feeding network is not required. The capability of flexible switching between multiple electromagnetic degrees of freedom opens pathways to new wireless applications, where fast beam steering and beamforming performances are required.
A hybrid quantum–classical neural network for learning transferable visual representation
Authors: Wang Ruhan , Richerme Philip , Chen Fan
Published: August 2023

State-of-the-art quantum machine learning (QML) algorithms fail to offer practical advantages over their notoriously powerful classical counterparts, due to the limited learning capabilities of QML algorithms, the constrained computational resources available on today’s noisy intermediate-scale quantum (NISQ) devices, and the empirically designed circuit ansatz for QML models. In this work, we address these challenges by proposing a hybrid quantum–classical neural network (CaNN), which we call QCLIP, for Quantum Contrastive Language-Image Pre-Training. Rather than training a supervised QML model to predict human annotations, QCLIP focuses on more practical transferable visual representation learning, where the developed model can be generalized to work on unseen downstream datasets. QCLIP is implemented by using CaNNs to generate low-dimensional data feature embeddings followed by quantum neural networks to adapt and generalize the learned representation in the quantum Hilbert space. Experimental results show that the hybrid QCLIP model can be efficiently trained for representation learning. We evaluate the representation transfer capability of QCLIP against the classical Contrastive Language-Image Pre-Training model on various datasets. Simulation results and real-device results on NISQ IBM_Auckland quantum computer both show that the proposed QCLIP model outperforms the classical CLIP model in all test cases. As the field of QML on NISQ devices is continually evolving, we anticipate that this work will serve as a valuable foundation for future research and advancements in this promising area.
A Transnational History of Intellectual Exchanges with the United States and the Shaping of Latin American Education
Authors: Rabelo Rafaela
Published: August 2023

At the beginning of the 20th century, the United States stood out internationally as a reference in pedagogical innovations and educational research. Teachers College (TC) at Columbia University in New York was one of the most renowned institutions that received students from many countries. Between the 1920s and 1940s, TC received more than 300 Latin American students. Some were already teachers or held administrative positions in their home countries. Upon their return, these Latin American educationalists promoted the circulation of what they had studied at TC by leading educational reforms, working on teacher training, and translating books. Later, several held prominent positions as university professors, in public administration, or as heads of research laboratories.
The facilitators and barriers to improving functional activity and wellbeing in people with dementia: a qualitative study from the process evaluation of Promoting Activity, Independence and Stability in Early Dementia (PrAISED)
Authors: Di Lorito Claudio , van der Wardt Veronika , Pollock Kristian , Howe Louise , Booth Vicky , Logan Pip , Gladman John , Masud Tahir , das Nair Roshan , Goldberg Sarah , Vedhara Kavita , O’Brien Rebecca , Adams Emma , Cowley Alison , Bosco Alessandro , Hancox Jennie , Burgon Clare , Bajwa Rupinder , Lock Juliette , Long Annabelle , Godfrey Maureen , Dunlop Marianne , Harwood Rowan H
Published: August 2023

Background

The PRomoting Activity, Independence and Stability in Early Dementia (PrAISED) study delivered an exercise and functional activity programme to participants living with dementia. A Randomised Controlled Trial showed no measurable benefits in activities of daily living, physical activity or quality of life.

Objective

To explore participants’ responses to PrAISED and explain why an intervention that might be expected to have produced measurable health gains did not do so.

Methods

A process evaluation using qualitative methods, comprising interviews and researcher notes.

Setting

Data were collected in participants’ homes or remotely by telephone or videoconferencing.

Sample

A total of 88 interviews were conducted with 44 participants living with dementia (n = 32 intervention group; n = 12 control group) and 39 caregivers. A total of 69 interviews were conducted with 26 therapists.

Results

Participants valued the intervention as proactively addressing health issues that were of concern to them, and as a source of social contact, interaction, information and advice. Facilitators to achieving positive outcomes included perceiving progress towards desired goals, positive expectations, therapists’ skills and rapport with participants, and caregiver support. Barriers included: cognitive impairment, which prevented independent engagement and carry-over between sessions; chronic physical health problems and intercurrent acute illness and injury; ‘tapering’ (progressively infrequent supervision intended to help develop habits and independent activity); and the COVID-19 pandemic.

Conclusions

Self-directed interventions may not be appropriate in the context of dementia, even in the mild stages of the condition. Dementia-specific factors affected outcomes including caregiver support, rapport with therapists, availability of supervision, motivational factors and the limitations of remote delivery. The effects of cognitive impairment, multimorbidity and frailty overwhelmed any positive impact of the intervention. Maintenance of functional ability is valued, but in the face of inevitable progression of disease, other less tangible outcomes become important, challenging how we frame ‘health gain’ and trial outcomes.
Differences and similarities in selenium biopathways in Astragalus, Neptunia (Fabaceae) and Stanleya (Brassicaceae) hyperaccumulators
Authors: van der Ent Antony , Salinitro Mirko , Brueckner Dennis , Spiers Kathryn M , Montanari Sofia , Tassoni Annalisa , Schiavon Michela
Published: August 2023

Background and Aims

Selenium hyperaccumulator species are of primary interest for studying the evolution of hyperaccumulation and for use in biofortification because selenium is an essential element in human nutrition. In this study, we aimed to determine whether the distributions of selenium in the three most studied hyperaccumulating taxa (Astragalus bisulcatus, Stanleya pinnata and Neptunia amplexicaulis) are similar or contrasting, in order to infer the underlying physiological mechanisms.

Methods

This study used synchrotron-based micro-X-ray fluorescence (µXRF) techniques to visualize the distribution of selenium and other elements in fresh hydrated plant tissues of A. racemosus, S. pinnata and N. amplexicaulis.

Key Results

Selenium distribution differed widely in the three species: in the leaves of A. racemosus and N. amplexicaulis selenium was mainly concentrated in the pulvini, whereas in S. pinnata it was primarilylocalized in the leaf margins. In the roots and stems of all three species, selenium was absent in xylem cells, whereas it was particularly concentrated in the pith rays of S. pinnata and in the phloem cells of A. racemosus and N. amplexicaulis.

Conclusions

This study shows that Astragalus, Stanleya and Neptunia have different selenium-handling physiologies, with different mechanisms for translocation and storage of excess selenium. Important dissimilarities among the three analysed species suggest that selenium hyperaccumulation has probably evolved multiple times over under similar environmental pressures in the US and Australia.
Pro-inflammatory cytokine IL1β1 participates in promoting parturition related pathways in the ovoviviparous teleost black rockfish (Sebastes schlegelii)
Authors: Yan Shaojing , Lyu Likang , Wang Xiaojie , Wen Haishen , Li Yun , Li Jianshuang , Yao Yijia , Zuo Chenpeng , Xie Songyang , Wang Zhijun , Qi Xin
Published: August 2023

Along with the evolution process, the reproductive strategies evolved including oviparity, viviparity and ovoviviparity, to fit the residential environment maximize the survival rate of the off spring. In mammals, the key to the initiation of parturition is the inflammatory response at the maternal-fetal interface. As a pro-inflammatory cytokine, interleukin 1 beta (IL1β) plays an important role in the process of human parturition. While less is known about IL1β1 in teleost parturition, identification of the functions of IL1β1 in inducing the parturition, black rockfish, an ovoviviparity teleost, which provides over 60% nutrition supply for over 50 000 embryos though a placenta like structure during pregnant, was employed as the research model. In the present study, based on the gene cloning, we detected the expression pattern of both Il1b1 and its receptor perinatal period, as well as the localization to the ovary by in situ hybridization. The different expression genes in transcriptomic data of perinatal primary ovarian cells treated with the recombinant IL1β1 (rIL1β1) obtained by prokaryotic expression system were analyzed. Differentially expressed genes, functional enrichment and pathway analysis mainly included immune response, signal transduction and cell death. In summary, our research provides novel insights into the potential role of IL1β1 in the parturition of ovoviviparity teleost.
MOY 2 MicroRNAs as Bile Based Biomarkers for Pancreaticobiliary Cancers (MIRABILE)
Authors: Liu Daniel S.K. , Prado Mireia Mato , Giovannetti Elisa , Jiao Long R. , Krell Jonathan , Frampton Adam E.
Published: August 2023

Aims

MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression at the post-transcriptional level. They are commonly deregulated in cancer and are incredibly stable molecules in tissues and biofluids. Accurate identification of a malignant biliary stricture can sometimes be challenging. We aimed to identify miRNAs in the bile that are able to differentiate between malignant (pancreatic ductal adenocarcinoma (PDAC) and cholangiocarcinoma (CCA)) and benign pancreaticobiliary disease.

Methods

There were 111 patients recruited prospectively at initial endoscopic retrograde cholangiopancreatography (ERCP) for obstructive jaundice and bile aspirated for analysis. Total cell-free RNA was extracted from the bile from a discovery cohort of patients (n=78: 27 PDAC, 14 CCA, and 37 benign disease) and small RNA sequencing was performed. LASSO regression analysis was used to define bile miRNA signatures, and NormFinder used to identify endogenous controls. A validation cohort was used (n=87: 34 PDAC, 14 CCA, and 39 benign disease) to confirm candidate miRNAs using TaqMan RT-qPCR.

Results

We identified 6 potential bile miRNAs, of which 4 were suitable for RT-qPCR validation. We found miR-340 and miR-182 were significantly differentially expressed (p=0.0268 and p=0.0004 respectively) in malignant vs. benign bile, with combined AUC of 0.80 (sensitivity 64.6%; specificity 82.1%) for predicting malignant pancreaticobiliary disease. Adding serum CA 19-9 to this bile miRNA model improved the diagnostic potential (AUC 0.85: sensitivity of 86.4%; specificity of 71.4%).

Conclusions

Bile obtained at ERCP contains miRNAs able to differentiate benign from malignant pancreaticobiliary disease. Our novel bile miRNAs can be used with serum CA 19-9 to rapidly detect CCA and PDAC in patients presenting with obstructive jaundice.
SP1.5 Mortality rate for frail and sarcopenic patients post emergency laparotomy
Authors: Ng Hwei Jene , Quasim Tara , Rattray Nicholas , Moug Susan
Published: August 2023

Aims

Frail patients and sarcopenic patients are predicted to have high morbidity and mortality after undergoing emergency laparotomy (EmLap). However frailty and sarcopenia can be present independently or mutually. We aim to explore the association between 30- day mortality, frailty and sarcopenia.

Methods

Analysis was performed on a prospectively collected database of EmLap patients ≥40 years in a busy district hospital. Frailty was assessed via Clinical Frailty Score with score ≥4 defined as frail. Sarcopenia was assessed via total psoas index (TPI). TPI is the total L3 psoas area on CT (cm2)/ patient’s height (m2), stratified according to gender with sarcopenia being present in the lowest quartile. Statistical analysis was performed using logistic regression and p value of <0.05 was considered significant.

Results

100 patients were included with a median age of 66 years; 59% were female. The overall 30- day mortality rate was 9%.

Frailty was present in 49% and within this group, mortality rate was 16.3% (OR 9.76, p= 0.012), 24% were sarcopenic and 30- day mortality was 12.5% (OR 1.57, p= 0.545). 14% of patients were both frail and sarcopenic and the 30- day mortality was 21.4% (OR 3.64, p= 0.080).

Conclusion

Mortality rate is high in EmLap patients and is higher when patients are both frail and sarcopenic. Frailty and sarcopenia are interlinked and can be improved, hence both should be assessed in all EmLap patients to allow early identification, improvement in shared decision making and development of targeted post-operative interventions to improve EmLap outcomes in this cohort of patients.
SP1.10 Predicting unplanned readmissions after emergency laparotomy
Authors: Brindley Ellie , McDermott Katherine , Slavin Emily , Downey Candice
Published: August 2023

Aims

St James’s University Hospital in Leeds performs the highest number of emergency laparotomies in the UK. This operation remains one of the highest risk surgical procedures but little is known about the patient journey after discharge from hospital. This service evaluation aimed to assess the rate of unplanned readmissions after discharge, and how to predict those at higher risk of readmission, to inform the implementation of a specialist emergency laparotomy follow-up clinic.

Methods

The Leeds NELA data were used to collate the clinical details of all patients who underwent an emergency laparotomy between 1st October 2021 – 1st October 2022. The local electronic patient record was searched to identify those who were readmitted within 30 days of discharge. A univariate analysis determined the factors which most accurately predict the risk of readmission.

Results

The clinical details of 343 patients were analysed, of whom 318 survived to discharge. There were 41 unplanned readmissions to hospital within 30 days of discharge (13%). The most frequent reasons for unplanned readmission were sepsis, wound infection, post-operative pain, high-output stoma and acute kidney injury. Frailty score (OR 1.276; CI 1.031-1.579; p=0.025) and ASA score (OR 1.803; CI 1.218-2.669; p=0.003) were statistically significant predictors of readmission after emergency laparotomy.

Conclusions

St James’s University Hospital employs two dedicated NELA nurses, and has implemented a weekly outpatient follow-up clinic for patients who have been discharged after emergency laparotomy. The availability of clinic appointments should be prioritised for frail and comorbid patients to enhance the patient’s postoperative journey.
SP2.6 Histological TNM stage and five-year survival after pancreatoduodenectomy for pancreatic ductal adenocarcinoma
Authors: Russell Thomas , Labib Peter , Aroori Somaiah ,   RAW Study Collaborators
Published: August 2023

Aims

Patients with a pancreatic ductal adenocarcinoma (PDAC) of the pancreatic head may be offered pancreatoduodenectomy (PD) providing they are suitable candidates. Unfortunately, recurrence rates are high following this operation and few patients achieve long-term survival. This study aimed to investigate and quantify the relationship between histological tumour, node and metastasis stage, and five-year survival.

Methods

Data were extracted from the Recurrence After Whipple’s (RAW) study, a multicentre retrospective cohort study of outcomes of PD performed for malignancy (29 centres from 8 countries, n=1484). PDAC patients were grouped by their T stage, N stage and M stage, and five-year survival rates were compared using Fisher’s exact test.

Results

A total of 885 patients (59.6%) had PDAC confirmed histologically. Five-year survival was 57.4%, 46.0%, 17.0% and 32.0% in patients with T1, T2, T3 and T4 disease, respectively (unavailable: 7 patients). T1-2 patients (vs T3-4) had significantly higher rates of five-year survival (OR: 4.8, 95% CI: 3.3-7.0). N0 patients (vs N1-2) had significantly higher rates of five-year survival (OR: 4.5, 95% CI: 3.2-6.3). M0 patients (vs M1) also had higher five-year survival rates but this was not quite significant due to the small sample size of the M1 group (OR: 3.8, 25.7% vs 8.3%, p=0.06).

Conclusion

In our multicentre study of patients who underwent PD for PDAC, increasing T and N histological stages were found to correlate with reduced five-year survival. The figures provided can be used to guide the consenting process and predict outcomes in individual patients.
SP2.9 An Audit on Implementation of Electronic Autofilling in Consent Forms for Liver Resections in a Tertiary Center
Authors: Iqbal Affan , Fadipe Adetokunbo , Patel Agastya , Bandyopadhyay Samik , Jamdar Saurabh , Satyadas Thomas
Published: August 2023

Background

As part of the GMC’s Good Medical Practice guidelines, benefits and risks should be discussed and documented accurately and in their entirety on a consent form. It is common for rarer or less significant complications or additional procedures to be missed from consent forms. Within the hepatopancreatobiliary (HPB) surgery team at Manchester Royal Infirmary, there has been a drive to evaluate the quality of the consenting process and documentation, as well as to understand the impact of the introduction of HIVE electronic patient record (EPR). Our aim is to standardize the consent forms to ensure all pertinent information are included.

Methods

We performed a comparison of documented risks and additional procedures against gold standard NICE guidance for liver resections performed by the HPB surgery department at Manchester Royal Infirmary. We evaluated paper consent forms from July to September 2022(n=9), electronically signed consent forms obtained from ‘HIVE’ from September to November 2022(n=29) and from December 2022 (n=19) we introduced ‘smart texts’ automated consent forms. Simple descriptive statistical analysis were used.

Results

Out of 20 documented risks and additional procedures, 15 were documented more frequently in consent forms following a transition to electronic patient records. Following ‘smart texts’, there was a further improvement in 14 of these risks and additional procedures. Particularly marked increase in documentation of additional procedures such as drains, lines and catheter insertion.

Conclusions

The introduction of HIVE and ‘smart texts’ have markedly improved the quality of the consenting process. We should be more comprehensive in educating patients about additional procedures that may be required.
SP3.1 80 patient series from UK renal transplant centre shows extended criteria deceased donor transplants are associated with a poorer graft function but at no increased risk of graft loss after 1 year
Authors: Abdul-Hamid Sawsan , Wong Zhen , Benaissa Mona , Lamb Rosemary
Published: August 2023

Aims

Between 12/2018 – 12/2021 our centre performed 163 deceased donor transplants. 30.7% of these utilised organs from so-called extended criteria donors (ECD). ECD [originally in context of donation after brain death (DBD), but later used also for donation after cardiac death (DCD)] refers to donors >60yo; or >50yo with ≥2 of hypertension / death from CVA / Cr >133. We wanted to assess outcomes in ECD transplant recipients and compare with outcomes of our standard donor (SCD) recipients.

Methods

Retrospective analysis of 40 ECD transplants (12/2018- 12/2021) and control group of 40 age-matched (overall mean age 58.2) SCD recipients with 12 month follow up.

Results

The groups were comparable regarding proportion of DCD donors (ECD 62.5%, SCD 50%; X2= 1.270 p=0.260).

Although rate of delayed graft function (DGF) was higher in the ECD group, this was not statistically significant (ECD: 62.5%, SCD:47.5%; X2=1.257 p=0.262). There was, however a difference in creatinine at discharge (median ECD:390; SCD:221; U= 1018.500; p=0.036) and in EGFR at 1 year (mean ECD:39.62; SCD: 54.3; t=-3.780 p<0.001).

There was no difference in incidence of graft loss (ECD:0%; SCD:2.5%; X2=1.013, p=0.314) or mortality (ECD:5.0%; SCD:7.5%; X2=0.213, p=0.644).

There was no difference in index length of stay (median ECD:6; SCD: 6; U=928.000 p=0.212), or total readmissions (median ECD:2.5; SCD:2.0; U=902.500 p=0.319).

Conclusions

In our sample incidence of DGF was similar between the two groups. ECD recipients had poorer graft function at 1 year but there was no evidence of increased risk of graft loss at 1 year.