bluuebunny/crossref_metadata_2025 huggingface dataset:
Cardiovascular Events in Patients with Severe Asthma—A Retrospective Study of Two Cohorts: Asthma Type T2 Treated with Biologics and Non-Type T2
Authors: Granda Paula , Villamañán Elena , Laorden Daniel , Carpio Carlos , Collada Victoria , Domínguez-Ortega Javier , de las Vecillas Leticia , Romero-Ribate David , Chaparro-Díaz Omar Fabián , Lázaro Miguel-Sin Teresa , Alloca-Álvarez Daniela Jose , Correa-Borit Jorge Mauricio , Losantos Itsaso , Mir-Ihara Patricia , Narváez-Fernández Emilio José , Quirce Santiago , Álvarez-Sala Rodolfo
Published: July 2024

Background: The prevalence of cardiovascular events (CVEs) in patients with asthma varies amongst studies, with little evidence as to their prevalence in patients treated with monoclonal antibodies (mAbs). In this retrospective, observational study, we aimed to evaluate the prevalence of CVEs in patients with T2 and non-T2 asthma and to identify risk factors associated with CVEs. Methods: A total of 206 patients with severe asthma were included. Demographic variables, respiratory comorbidities and cardiovascular risk factors were collected, along with respiratory function, laboratory parameters and respiratory pharmacotherapy, including treatment with mAbs. Results: A total of 10.7% of the patients had any CVE from the date of asthma diagnosis, with a higher risk in those patients with chronic obstructive pulmonary disease (odds ratio [OR] = 5.36, 95% CI 1.76–16.31; p = 0.003), arterial hypertension (OR = 2.71, 95% CI 1.13–6.55; p = 0.026) and dyslipidaemia (OR = 9.34, 95% CI 3.57–24.44; p < 0.001). No association between mAb treatment and a CVE or between time of mAb treatment and the event was found. No significant differences were observed between the T2 and non-T2 cohort. After a multivariate analysis, dyslipidaemia was identified as an independent risk factor (OR = 13.33, 95% CI 4.49–39.58; p < 0.001), whereas regular use of inhaled corticosteroids was associated with a reduced risk of a CVE (OR = 0.103, 95% CI 0.021–0.499; p = 0.005). Further research is needed to fully understand the relationship between severe asthma and CVEs. Conclusions: This study suggests that patients with severe asthma experience a higher percentage of CVEs compared with the general population.
Renal Replacement Therapy in Methylmalonic Aciduria-Related Metabolic Failure: Case Report and Literature Review
Authors: Pintus Giovanni , Vitturi Nicola , Carraro Gianni , Lenzini Livia , Gugelmo Giorgia , Fasan Ilaria , Madinelli Alberto , Burlina Alberto , Avogaro Angelo , Calò Lorenzo Arcangelo
Published: July 2024

Background: Methylmalonic Aciduria (MA) without homocystinuria (or isolated MA) is a group of rare inherited metabolic disorders which leads to the accumulation of methylmalonic acid (MMA), a toxic molecule that accumulates in blood, urine, and cerebrospinal fluid, causing acute and chronic complications including metabolic crises, acute kidney injury (AKI), and chronic kidney disease (CKD). Detailed Case Description: Herein, we report a case of a 39-year-old male with MA and stage IV CKD who experienced acute metabolic decompensation secondary to gastrointestinal infection. The patient underwent a single hemodialysis (HD) session to correct severe metabolic acidosis unresponsive to medical therapy and to rapidly remove MMA. The HD session resulted in prompt clinical improvement and shortening of hospitalization. Discussion: MMA accumulation in MA patients causes acute and life-threatening complications, such as metabolic decompensations, and long-term complications such as CKD, eventually leading to renal replacement therapy (RRT). Data reported in the literature show that, overall, all dialytic treatments (intermittent HD, continuous HD, peritoneal dialysis) are effective in MMA removal. HD, in particular, can be useful in the emergency setting to control metabolic crises, even with GFR > 15 mL/min. Kidney and/or liver transplantations are often needed in MA patients. While a solitary transplanted kidney can be rapidly affected by MMA exposure, with a decline in renal function even in the first year of follow-up, the combined liver–kidney transplantation showed better long-term results due to a combination of reduced MMA production along with increased urinary excretion. Conclusions: Early diagnosis, multidisciplinary management and preventive measures are pivotal in MA patients to avoid recurrent AKI episodes and, consequently, to slow down CKD progression.
Errors in Radiology: A Standard Review
Authors: Pesapane Filippo , Gnocchi Giulia , Quarrella Cettina , Sorce Adriana , Nicosia Luca , Mariano Luciano , Bozzini Anna Carla , Marinucci Irene , Priolo Francesca , Abbate Francesca , Carrafiello Gianpaolo , Cassano Enrico
Published: July 2024

Radiological interpretations, while essential, are not infallible and are best understood as expert opinions formed through the evaluation of available evidence. Acknowledging the inherent possibility of error is crucial, as it frames the discussion on improving diagnostic accuracy and patient care. A comprehensive review of error classifications highlights the complexity of diagnostic errors, drawing on recent frameworks to categorize them into perceptual and cognitive errors, among others. This classification underpins an analysis of specific error types, their prevalence, and implications for clinical practice. Additionally, we address the psychological impact of radiological practice, including the effects of mental health and burnout on diagnostic accuracy. The potential of artificial intelligence (AI) in mitigating errors is discussed, alongside ethical and regulatory considerations in its application. This research contributes to the body of knowledge on radiological errors, offering insights into preventive strategies and the integration of AI to enhance diagnostic practices. It underscores the importance of a nuanced understanding of errors in radiology, aiming to foster improvements in patient care and radiological accuracy.
Clinical Management of Postoperative Growth Hormone Deficiency in Hypothalamic-Pituitary Tumors
Authors: Iglesias Pedro
Published: July 2024

The present review focuses on growth hormone (GH) deficiency in pediatric and adult patients following surgery for hypothalamic-pituitary tumors, with a special emphasis on hormone replacement therapy with recombinant human growth hormone (rhGH). The symptoms and metabolic changes associated with GH deficiency are reviewed, and the potential risks and therapeutic outcomes of rhGH treatment in these patients are discussed. This review emphasizes the importance of rhGH in the normalization of growth in children and the improvement of quality of life (QoL) and metabolic health in adults. Aspects related to efficacy, safety, dosage, duration of treatment, and QoL in this population are analyzed. The need for regular follow-up and dose adjustment to maintain the optimal IGF-I levels in these patients is emphasized, as is the importance of individualized assessment and collaboration with a specialized multidisciplinary medical team to make the appropriate therapeutic decisions. Furthermore, continuous follow-up are necessary to optimize the clinical outcomes in this patient population.
Prevention and Treatment of Skin Pigmentation Disorders
Authors: Khamaysi Ziad , Jiryis Badea
Published: July 2024

Pigmentation disorders are conditions that affect the color of a person’s skin [...]
Complications of Balloon Pulmonary Angioplasty: A Comprehensive Analysis Based on the Latest ESC Consensus Statement
Authors: van Leusden Fe J. , Staal Diederik P. , van Thor Mitch C. J. , Rensing Benno J. M. W. , van Kuijk Jan-Peter , Mulder Berend M. , van den Heuvel Daniël A. F. , Boerman Sanne , Boomars Karin A. , Peper Joyce , Mager Johannes J. , Post Marco C.
Published: July 2024

Background/Objectives: The literature reports high complication rates in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who undergo balloon pulmonary angioplasty (BPA), especially in patients with poor pulmonary hemodynamics. Here, we describe the complications of BPA based on the new definitions. Methods: All patients with CTEPH who completed BPA treatment before 15 September 2023 were selected from the CTEPH database. Peri-procedural complications were collected and classified according to the 2023 consensus paper on BPA treatment. Complications were analyzed in subgroups of patients with pulmonary vascular resistance (PVR), ≤ or >6.6 WU, and mean pulmonary artery pressure (mPAP), ≤ or >45 mmHg, at first BPA. Results: In this analysis, 87 patients (63% women; mean age 61.1 ± 14.0 years; 62% on dual PH targeted medical therapy) underwent 426 (mean 4.9 ± 1.6 per patient) BPAs. Only non-severe complications occurred in 14% of BPA treatments and in 47% of the patients; 31% patients had a thoracic complication. The thoracic complications were mild (71%) or moderate (29%). Patients with a PVR > 6.6 WU (n = 8) underwent more BPA treatments (6.6 ± 1.5 versus 4.6 ± 1.5, p = 0.002), had more complications (88% versus 41% of patients, p = 0.020), and had more thoracic complications (17% vs. 7% of BPAs, p = 0.013) than patients with PVR ≤ 6.6 WU. Patients with mPAP > 45 mmHg (n = 13) also had more BPA treatments (6.5 ± 1.7 versus 4.6 ± 1.4, p < 0.001), more complications (77% versus 44% of patients, p = 0.027) and more thoracic complications (14% versus 8% of BPAs, p = 0.039) than patients with mPAP ≤ 45 mmHg. Conclusions: Complications occurred in 14% of BPAs and were mostly mild. Patients with severe pulmonary hemodynamics suffered more (thoracic) complications.
Recent Advances and Perspectives in Anesthesiology: Towards Artificial Intelligence-Based Applications
Authors: Cascella Marco , Innamorato Massimo Antonio , Simonini Alessandro
Published: July 2024

In recent years, the field of anesthesiology has seen remarkable advancements in patient safety, comfort, and outcomes [...]
Recurrence Rate during 5-Year Period after Suspension of Anti-Vascular Endothelial Growth Factor Treatment for Neovascular Age-Related Macular Degeneration
Authors: Chujo Shinichiro , Matsubara Hisashi , Mase Yoko , Kato Kumiko , Kondo Mineo
Published: July 2024

Purpose: To determine the recurrence rate of neovascular age-related macular degeneration (nAMD) during a 5-year period after the suspension of anti-vascular endothelial growth factor (anti-VEGF) treatments. Methods: Thirty-four eyes of 34 nAMD patients who met the inclusion criteria and were treated by anti-VEGF drugs were studied. All met the treatment suspension criteria and were followed for 5 years after the suspension of the anti-VEGF treatment. Patients with a recurrence within one year were placed in Group A, and patients with a recurrence between 1 and 5 years were placed in Group B. The rate and time of a recurrence were analyzed using the Kaplan–Meier method. We also examined whether there were differences in the baseline factors of age, sex, subtype, treatment period, and treatment interval between Groups A and B. Results: Twenty-five of 34 eyes (73.5%) had a recurrence within 5 years of stopping the anti-VEGF treatments. Thirteen (52.0%) of the 25 eyes had a recurrence within 1 year, 4 (16.0%) eyes between 1 and 2 years, 4 (16.0%) eyes between 2 and 3 years, 2 (8%) between 3 and 4 years, and 2 eyes (8%) between 4 and 5 years. The baseline factors were not significantly different between Groups A and B. Conclusions: The results showed that the recurrence rate was highest within one year after the suspension of the anti-VEGF treatments, with a number of recurrences one year after the suspension. Clinicians should remember that nAMD may recur several years after the suspension of anti-VEGF treatments.
Pulse Pressure as a Hemodynamic Parameter in Preeclampsia with Severe Features Accompanied by Fetal Growth Restriction
Authors: Sampson Rachael , Davis Sidney , Wong Roger , Baranco Nicholas , Silverman Robert K.
Published: July 2024

Background: Modern management of preeclampsia can be optimized by tailoring the targeted treatment of hypertension to an individual’s hemodynamic profile. Growing evidence suggests different phenotypes of preeclampsia, including those with a hyperdynamic profile and those complicated by uteroplacental insufficiency. Fetal growth restriction (FGR) is believed to be a result of uteroplacental insufficiency. There is a paucity of research examining the characteristics of patients with severe preeclampsia who do and who do not develop FGR. We aimed to elucidate which hemodynamic parameters differed between these two groups. Methods: All patients admitted to a single referral center with severe preeclampsia were identified. Patients were included if they had a live birth at 23 weeks of gestation or higher. Multiple gestations and pregnancies complicated by fetal congenital anomalies and/or HELLP syndrome were excluded. FGR was defined as a sonographic estimation of fetal weight (EFW) < 10th percentile or abdominal circumference (AC) < 10th percentile. Results: There were 76% significantly lower odds of overall pulse pressure upon admission for those with severe preeclampsia comorbid with FGR (aOR = 0.24, 95% CI = 0.07–0.83). Advanced gestational age on admission was associated with lower odds of severely abnormal labs and severely elevated diastolic blood pressure in preeclampsia also complicated by FGR. Conclusions: Subtypes of preeclampsia with and without FGR may be hemodynamically evaluated by assessing pulse pressure on admission.
IPINeT Ped-unPAD Study: Goals, Design, and Preliminary Results
Authors: Sgrulletti Mayla , Baselli Lucia Augusta , Castagnoli Riccardo , Del Duca Elisabetta , Graziani Simona , Moscato Giusella Maria Francesca , Di Cesare Silvia , Di Matteo Gigliola , Cifaldi Cristina , Rossano Martina , Ballerini Claudia , Piciocchi Alfonso , Licari Amelia , Marseglia Gian Luigi , Consolini Rita , Moschese Viviana
Published: July 2024

Background: An unclassified primary antibody deficiency (unPAD) is a widely heterogeneous clinical entity, recently identified within the spectrum of Inborn Errors of Immunity (IEIs). Since unPAD has been traditionally considered as a mild condition, it has incorrectly received little attention, resulting in the paucity of extensive and comparable studies describing its natural history. To address the gaps in characterizing, understanding, and managing pediatric unPAD patients, the Italian Primary Immunodeficiency Network (IPINet) Ped-unPAD study has recently been launched. Methods: Seventeen IPINeT Centers have expressed interest to participate, and data collection is still on-going. Hereby, we anticipate preliminary key issues emerging from the first 110 enrolled patients, attending three IPINet Centers. Results: A proportion of unPAD patients have experienced a severe infectious phenotype, which required hospitalization in a quarter of patients and antibiotic prophylaxis or Immunoglobulin Replacement Therapy in approximately 10% of patients. In this partial cohort, a mean follow-up (FU) of 5 years confirmed unPAD diagnosis in fifty percent of cases, with the remaining being reclassified as the Transient Hypogammaglobulinemia of Infancy (25%) and other IEIs (25%), such as a Common Variable Immunodeficiency, Selective IgA deficiency, Selective IgM deficiency, and IgG3 subclass deficiency. Conclusions: Despite a phenotype overlap at diagnosis, clinicians should be aware that unPAD is a mutable condition that deserves comprehensive evaluation and long-term monitoring to dissect the final diagnosis for optimal treatment.
Clinical Significance and Microbiological Characteristics of Staphylococcus lugdunensis in Cutaneous Infections
Authors: Koumaki Dimitra , Maraki Sofia , Evangelou Georgios , Rovithi Evangelia , Petrou Danae , Apokidou Erato Solia , Gregoriou Stamatios , Koumaki Vasiliki , Ioannou Petros , Zografaki Kyriaki , Doxastaki Aikaterini , Papadopoulou Kalliopi , Stafylaki Dimitra , Mavromanolaki Viktoria Eirini , Krasagakis Konstantinos
Published: July 2024

Background/Objectives: Staphylococcus lugdunensis is a coagulase-negative staphylococcus (CoNS) commonly found on human skin. Unlike other CoNS, S. lugdunensis has a notable potential to cause severe infections comparable to Staphylococcus aureus. This study aimed to characterize the clinical and microbiological profile of patients with S. lugdunensis skin infections at a single center. Methods: We conducted a retrospective analysis of patient records from the Dermatology Department of the University Hospital of Heraklion, Greece, covering the period from January 2014 to January 2024. Patients’ clinical presentations, demographics, infection sites, comorbidities, prior infections, antimicrobial treatments, and therapeutic responses were examined. Specimens were collected, transported, and processed according to standardized microbiological protocols. Bacterial identification and antibiotic susceptibility testing were performed using the Vitek 2 automated system and MALDI-TOF MS, with results interpreted according to Clinical and Laboratory Standards Institute (CLSI) criteria. Results: A total of 123 skin specimens positive for S. lugdunensis were analyzed. The cohort comprised 62 males (50.4%) and 61 females (49.6%), with a mean age of 40.24 ± 20.14 years. Most specimens were collected from pus (84%), primarily from below the waist (66.7%). Hidradenitis suppurativa (26%) was the most common condition associated with S. lugdunensis, followed by folliculitis, abscesses, ulcers, cellulitis, and acne. Co-infections with other bacteria were noted in 49.6% of cases, and 25.2% of infections were nosocomially acquired. The majority of patients (65%) received systemic antibiotics, predominantly amoxicillin/clavulanic acid, cefuroxime axetil, and doxycycline, with a cure rate of 100%. All isolates were susceptible to several antibiotics, though resistance to penicillin (28.5%) and clindamycin (36%) was observed. Conclusions: S. lugdunensis is a significant pathogen in skin infections, capable of causing severe disease. The high cure rate demonstrates the effectiveness of appropriate antibiotic therapy. Continued monitoring and antimicrobial stewardship are essential to manage resistance and ensure effective treatment.
Cervical and Thoracic Spine Mobility in Rotator Cuff Related Shoulder Pain: A Comparative Analysis with Asymptomatic Controls
Authors: Manoso-Hernando Daniel , Bailón-Cerezo Javier , Elizagaray-García Ignacio , Achútegui-García-Matres Pablo , Suárez-Díez Guillermo , Gil-Martínez Alfonso
Published: July 2024

Rotator cuff related shoulder pain (RCRSP) is a prevalent clinical presentation characterized by substantial diagnostic uncertainty. Some of this uncertainty relates to the involvement of the cervical and thoracic spine as a source of or contributing factor to RCRSP. Thirty-two RCRSP cases and thirty-two asymptomatic controls (AC), recruited from Hospital La Paz-Carlos III between March 2023 and September 2023, were matched for age, gender and hand dominance. Assessed variables included cervical, thoracic range of motion (ROM) and neck disability index (NDI). Independent t-tests were used to compare each of these measurements and multiple linear regression was used to examine the capacity of neck or psychosocial variables to predict the variability of the NDI. The RCRSP group had significantly reduced cervical rotation [RCRSP (111.14 ± 22.98); AC (130.23 ± 21.20), d = 0.86, p < 0.01] and flexo-extension ROM [RCRSP (112.47 ± 2.07); AC (128.5 ± 17.85), d = 0.80, p < 0.01] as well as thoracic spine flexion [RCRSP (33.02 ± 1.14); AC (34.14 ± 1.01), d = 1.04, p < 0.01], extension [RCRSP (28.63 ± 0.89); AC (27.37 ± 0.89), d = −1.40, p < 0.01], right rotation [RCRSP (40.53 ± 10.39); AC (54.45 ± 9.75), d = 1.38, p < 0.01], left rotation [RCRSP (39.00 ± 11.26); AC (54.10 ± 10.51), d = 1.39, p < 0.01] and a significantly increased NDI score [RCRSP (17.56 ± 7.25); AC (2.47 ± 3.25), d = −2.69, p < 0.01]. The variables best explaining neck disability were central sensitization index and SF-12 total score (adjusted R2 = 0.75; p < 0.01). These results suggest that clinicians should assess cervical and thoracic spine mobility in patients with RCRSP.
Iterative Tomographic Image Reconstruction Algorithm Based on Extended Power Divergence by Dynamic Parameter Tuning
Authors: Yabuki Ryuto , Yamaguchi Yusaku , Abou Al-Ola Omar M. , Kojima Takeshi , Yoshinaga Tetsuya
Published: July 2024

Computed tomography (CT) imaging plays a crucial role in various medical applications, but noise in projection data can significantly degrade image quality and hinder diagnosis accuracy. Iterative algorithms for tomographic image reconstruction outperform transform methods, especially in scenarios with severe noise in projections. In this paper, we propose a method to dynamically adjust two parameters included in the iterative rules during the reconstruction process. The algorithm, named the parameter-extended expectation-maximization based on power divergence (PXEM), aims to minimize the weighted extended power divergence between the measured and forward projections at each iteration. Our numerical and physical experiments showed that PXEM surpassed conventional methods such as maximum-likelihood expectation-maximization (MLEM), particularly in noisy scenarios. PXEM combines the noise suppression capabilities of power divergence-based expectation-maximization with static parameters at every iteration and the edge preservation properties of MLEM. The experimental results demonstrated significant improvements in image quality in metrics such as the structural similarity index measure and peak signal-to-noise ratio. PXEM improves CT image reconstruction quality under high noise conditions through enhanced optimization techniques.
A Decoupled Buckling Failure Analysis of Buried Steel Pipeline Subjected to the Strike-Slip Fault
Authors: Asgarihajifirouz Mozhgan , Dong Xiaoyu , Shiri Hodjat
Published: July 2024

Over the past few years, there has been an increased focus on offshore pipeline safety due to the development of offshore oil and gas resources. Both onshore and offshore pipelines may face significant geological hazards resulting from active faults. Pre-excavated soil can be used as backfill for trenches to prevent major pipeline deformations. Since these backfill materials have been heavily remolded, they are softer than the native soil. Therefore, the difference in shear strength between the backfill and native ground may have an effect on the interaction between the pipeline and the backfill. In this paper, the pipeline–backfill–trench interaction is investigated using a hybrid beam–spring model. The P-Y curves obtained from CEL analysis are incorporated into a 3D beam–spring model to analyze the pipeline’s response to lateral strike-slip faults. Additionally, the nonlinearity of pipeline materials is considered to study pipeline failure modes under strike-slip fault movements. A series of parametric studies were conducted to explore the effects of fault intersection angle, pipe diameter, buried depth of the pipe, and soil conditions on the failure modes of buckling pipelines. The developed method can be used to analyze and assess pipeline–backfill–trench interaction when subjected to strike-slip fault displacements.
The Determinants of the Efficiency of Microfinance Institutions in Africa
Authors: Zineelabidine Maroua , Nafssi Fadwa , Ayass Hamza
Published: July 2024

Over the past few decades, microfinance institutions have attracted the interest of governments and academics alike, given their unique nature of being financial institutions with a dual mission of promoting social development and reducing poverty. However, concerns have been raised about their effectiveness in achieving these goals while remaining financially sustainable. In this study, we attempt to examine the factors that have the greatest impact on the social, financial, and overall efficiency of microfinance institutions in African regions. We adopt a two-step approach: First, we assess the efficiency scores of 95 microfinance institutions in Africa between 2005 and 2018 using a data envelopment analysis (DEA) approach. We then regress their efficiency scores on a set of determinant variables, capturing the microfinance institutions’ characteristics. Our findings suggest that a majority of institutions prioritize profitability over social outreach. Furthermore, the panel data regression indicates that factors such as profitability, equity capitalization, types of loans, and low gross domestic product (GDP) have a positive influence on microfinance institutions’ efficiency. Conversely, variables including their risk portfolio, grants, microfinance institution status (Non-Governmental Organization (NGO), cooperative, etc.), operational area, political environment, and size exert a negative impact on efficiency. Through this study, we seek to enhance our understanding of microfinance institutions and to identify the factors that impact their operational efficiency, thereby reinforcing their crucial role in advancing financial inclusion, empowering marginalized communities, and fostering inclusive economic growth.
Urban Fire Risk Dynamics and Mitigation Strategies in Shanghai: Integrating Spatial Analysis and Game Theory
Authors: Yao Manqing , Zhang Deshun , Chen Yingying , Liu Yujia , Elsadek Mohamed
Published: July 2024

In recent decades, the increasing frequency of urban fires, driven by urban functional enhancements and climate change, has posed a growing threat to metropolitan sustainability. This study investigates the temporal and spatial characteristics of fire incidents in Shanghai from 2019 to 2023. Using satellite fire point data and official government records, kernel density analysis and wavelet analysis were employed to analyze the time series and spatial distribution of fire data. Subsequently, eleven primary factors influencing urban fire occurrence were identified, encompassing probability, regional characteristics, and hazard sources. A combined methodology of subjective and objective weights with game theory was used to generate a fire risk assessment at a 1 × 1 km2 grid scale. Furthermore, the spatial distribution characteristics of the assessments were analyzed. The results reveal that the downtown area exhibits the highest intensity of urban fires in terms of spatial domain, with a decreasing intensity towards the suburbs. Temporally, fire frequency demonstrates significant periodicity at an 18a time scale, while clear seasonal fluctuations and periodicity are observed at a 16-22a time scale, with higher occurrences in spring and winter. The study identifies typical aggregation patterns of urban fires, with high-risk centers in downtown Shanghai. Considering the impact of climate change and human activities, high-risk areas may gradually expand to adjacent urban suburbs, presenting a concerning future scenario. By examining the dual attributes of “combustibles and fireproof space” within urban greening systems, this research offers recommendations for the future strategies of disaster prevention and mitigation of green systems in Shanghai.
Designing Food Hubs for Territories of Proximity: Assessing the Spatial, Ecological, and Cultural Potentials of Places through Multi-Criteria Decision Support Systems
Authors: Favargiotti Sara , Zantedeschi Giulia , Pianegonda Angelica , Brunelli Matteo , Urbani Michele
Published: July 2024

Logistics, distribution models, and landscapes of food production strongly influence the space of our cities and territories. In addition to the network of large-scale retail distribution that is diffused in urban and non-urban areas, with this contribution, we study the presence of new forms of the local and sustainable distribution of food (such as Alternative Food Networks, and community-supported agriculture). Studying and understanding how these distribution models can support and be integrated within a landscape planning and design approach is explored through the Analytic Hierarchy Process (AHP), a multi-criteria decision analysis method. Through the specific focus of a Food Hub localization, the aim is to demonstrate how distribution models can not only support but also integrate into landscape planning and design. The fundamental objectives for structuring and locating a Food Hub can be organized under three strategic objectives: pursuing the benefit of people, the planet, and profit. The choice of one distribution method over others, or what is the best location and condition for distribution centers, is the question we have tested with the collaboration of “L’Ortazzo” Association. The case study is a solidarity purchasing group located in the upper Valsugana valley area (Trentino Region, Italy), a supra-municipality reality involving about a hundred families that, currently, do not have a physical distribution center.
Trimethylsilane Plasma-Nanocoated Silver Nanowires for Improved Stability
Authors: Liao Yixuan , Zhao Ganggang , Ling Yun , Yan Zheng , Yu Qingsong
Published: July 2024

The objective of this study was to evaluate the effectiveness of trimethylsilane (TMS) plasma nanocoatings in protecting silver nanowires (AgNWs) from degradation and thus to improve their stability. TMS plasma nanocoatings at various thicknesses were deposited onto AgNWs that were prepared on three different substrates, including glass, porous styrene-ethylene-butadiene-styrene (SEBS), and poly-L-lactic acid (PLLA). The experimental results showed that the application of TMS plasma nanocoatings to AgNWs induced little increase, up to ~25%, in their electrical resistance but effectively protected them from degradation. Over a two-month storage period in summer (20–22 °C, 55–70% RH), the resistance of the coated AgNWs on SEBS increased by only ~90%, compared to a substantial increase of ~700% for the uncoated AgNWs. On glass, the resistance of the coated AgNWs increased by ~30%, versus ~190% for the uncoated ones. When stored in a 37 °C phosphate-buffered saline (PBS) solution for 2 months, the resistance of the coated AgNWs on glass increased by ~130%, while the uncoated AgNWs saw a ~970% rise. Increasing the TMS plasma nanocoating thickness further improved the conductivity stability of the AgNWs. The nanocoatings also transformed the AgNWs’ surfaces from hydrophilic to hydrophobic without significantly affecting their optical transparency. These findings demonstrate the potential of TMS plasma nanocoatings in protecting AgNWs from environmental and aqueous degradation, preserving their electrical conductivity and suitability for use in transparent electrodes and wearable electronics.
A Detailed Properties Comparison of an Automotive Sealant Nozzle Produced Using Three Metal Additive Manufacturing Technologies
Authors: Ortiz-Cañavate Jaime , Ferrandiz Santiago , Bloem Carlos A. , Igual Javier , Blasco Jose Ramon
Published: July 2024

Choosing the right metal AM equipment and material is a highly intricate process that forms a crucial part of every manufacturing company’s strategic plan. This study undertakes a comprehensive comparison of the performance and material properties of three Metal Additive Manufacturing (AM) technologies: Powder Bed Fusion (PBF), Metal Filament Deposition Modeling (MFDM), and Bound Metal Deposition (BMD). An automotive nozzle was selected and manufactured using all three technologies and three metallic materials to understand their respective advantages and disadvantages. The samples were then subjected to a series of tests and evaluations, including dimensional accuracy, mechanical properties, microstructure, defects, manufacturability, and cost efficiency. The nozzle combinations were PBF in aluminum, MFDM in stainless steel, and BMD in hard tool steel. The results underscore significant differences in functionality, material characteristics, product quality, lead time, and cost efficiency, all of which are crucial factors in making equipment investment decisions. The conclusions drawn in this paper aim to assist automotive industry equipment experts in making informed decisions about the technology and materials to use for parts with characteristics like these. Future studies will delve into other technologies, automotive components, and materials to further enhance our understanding of the application of metal AM in manufacturing.
A Performance-Based Test for Mitigating the Risk of Geopolymer Concrete Surface Efflorescence Due to Alkali Leaching
Authors: Babaee Mahdi , Castel Arnaud
Published: July 2024

Geopolymer concretes are considered to be a potential sustainable, low-embodied carbon alternative for Ordinary Portland Cement (OPC) concrete. Alkali leaching is considered to be a major esthetic concern for Na-silicate-based geopolymers as it can lead to the formation of efflorescence products on the surfaces of concrete members exposed to humidity. In this context, this research aims to investigate the effect of the alkali content and the FA/GGBS mass ratio on the alkali leaching and formation of the efflorescence products. Paste cylinders were fabricated and cured in ambient conditions. Samples were submerged in deionized water and the concentration of the leached-out ions was measured. Efflorescence potential was also investigated by partial immersion of the samples in deionized water. The results highlight the complexity of the interacting parameters governing the formation of efflorescence products in geopolymer materials. Establishing relationships between the concrete mix variables and the risk of efflorescence seems unfeasible particularly because of the wide range of possible precursors and activators available to design geopolymer concrete mixes. To overcome this barrier, a practical performance-based testing method is developed. For the first time, by testing a wide range of geopolymer materials, performance-based requirements associated with the risk of efflorescence for geopolymer concrete surfaces exposed to humidity are calibrated. Four categories of risk are proposed and typical suitable exposure conditions for geopolymer concrete surfaces are suggested for each risk category.
Rapid, Selective, and Ultra-Sensitive Field Effect Transistor-Based Detection of Escherichia coli
Authors: Zaidan Liena , Novodchuk Inna , H.Xu Alexander , Nica Alexandru , Takaloo Saeed , Lloyd Christopher , Karimi Reza , Sanderson Joe , Bajcsy Michal , Yavuz Mustafa
Published: July 2024

Escherichia coli (E. coli) was among the first organisms to have its complete genome published (Genome Sequence of E. coli 1997 Science). It is used as a model system in microbiology research. E. coli can cause life-threatening illnesses, particularly in children and the elderly. Possible contamination by the bacteria also results in product recalls, which, alongside the potential danger posed to individuals, can have significant financial consequences. We report the detection of live Escherichia coli (E. coli) in liquid samples using a biosensor based on a field-effect transistor (FET) biosensor with B/N co-coped reduced graphene oxide (rGO) gel (BN-rGO) as the transducer material. The FET was functionalized with antibodies to detect E. coli K12 O-antigens in phosphate-buffered saline (PBS). The biosensor detected the presence of planktonic E. coli bacterial cells within a mere 2 min. The biosensor exhibited a limit of detection (LOD) of 10 cells per sample, which can be extrapolated to a limit of detection at the level of a single cell per sample and a detection range of at least 10–108 CFU/mL. The selectivity of the biosensor for E. coli was demonstrated using Bacillus thuringiensis (B. thuringiensis) as a sample contaminant. We also present a comparison of our functionalized BN-rGO FET biosensor with established detection methods of E. coli k12 bacteria, as well as with state-of-the-art detection mechanisms.
A Study on the Surface Oxidation Pretreatment and Nickel Plating Mechanism of Carbon Fiber
Authors: Wang Qinghui , Li Xuesong , Zhu Dongdong
Published: July 2024

This study explores the effects of various temperatures on the surface modification of carbon fibers, as well as the effect of differing voltages and currents on the morphology, deposition rate, and thickness of the Ni plating layers. Post-treatment characterization of the samples was conducted utilizing scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) methods, thus facilitating a discussion on the mechanism of Ni plating. The findings demonstrate that at a temperature of 500 °C, the carbon fiber surface exhibits the highest concentration of functional groups, including hydroxyl (-OH), carboxyl (-COOH), and carbonyl (-C=O), resulting in the most efficacious modification. Specifically, exceeding 500 °C leads to significant carbon fiber mass loss, compromising the reinforcement effect. Under a stable voltage of 7.5 V, the Ni-plated layer on the carbon fibers appear smooth, fine, uniform, and complete. Conversely, at a voltage of 15 V, the instantaneous high voltage induces the continuous growth of Ni2+ ions along a singular deposition point, forming a spherical Ni-plated layer. In addition, a current of 0.6 A yields a comparatively uniform and dense carbon fiber coating. Nickel-plated layers on a carbon fiber surface with different morphologies have certain innovative significance for the structural design of composite reinforcements.
Impact of Water–Cement Ratio on Concrete Mechanical Performance: Insights into Energy Evolution and Ultrasonic Wave Velocity
Authors: Lin Junzhi , Tian Bincheng , Liang Zelong , Hu Enpeng , Liu Zhaocun , Wang Kui , Sang Tao
Published: July 2024

The water–cement ratio significantly affects the mechanical properties of concrete with changes in porosity serving as a key indicator of these properties, which are correlated with the ultrasonic wave velocity and energy evolution. This study conducts uniaxial compression tests on concrete with varying water–cement ratios, analyzing energy evolution and ultrasonic wave velocity variations during the pore compaction stage and comparing damage variables defined by dissipated energy and ultrasonic wave velocity. The results indicate the following findings. (1) Higher water–cement ratios lead to more complete hydration, lower initial porosity, and a less pronounced pore compaction stage, but they deteriorate mechanical properties. (2) In the pore compaction stage, damage variables defined by dissipated energy are more regular than those defined by ultrasonic wave velocity, showing a nearly linear increase with stress (D = 0~0.025); ultrasonic wave variables fluctuate within −0.06 to 0.04 due to diffraction caused by changes in the pore medium. (3) In the pre-peak stress stage, damage variables defined by ultrasonic wave velocity show a distinct threshold. When the stress ratio exceeds about 0.3, the damage variable curve’s growth shows clear regularity, significantly reflecting porosity changes. In conclusion, for studying porosity changes during the pore compaction stage, damage variables defined by dissipated energy are more effective.
Electrical Conduction Mechanism of Mg-Doped ZrO2 Thin Films
Authors: Mardare Diana , Frenti Mariana , Mita Carmen , Cornei Nicoleta , Bulai Georgiana , Dobromir Marius , Doroshkevich Alexandr , Yildiz Abdullah
Published: July 2024

Amorphous ZrO2 thin films with increasing Mg content were deposited on quartz substrates, by dip coating method. The films are transparent in the visible domain and absorbent in UV, with an optical band gap that decreases with the increase of Mg content, from 5.42 eV to 4.12 eV. The temperature dependent conductivity measurements showed typical semiconductor comportment. The decrease of the electrical conductivity by Mg doping was related to the increase of the OH groups (37% to 63%) as seen from X-ray Photoelectron Spectroscopy. It was found out that the electrical conductivity obeys the Meyer-Neldel rule. This rule, previously reported for different disordered material systems is obtained for ZrO2 for the first time in the literature. Exploring novel aspects of Mg-doped ZrO2, the present study underscores the origin of the Meyer-Neldel rule explained by the small-polaron hopping model in the non-adiabatic hopping regime. Determination of the presence of such a conduction mechanism in the samples hold promise for comprehending the important aspects, which might be a concern in developing various devices based on Mg-doped ZrO2.
Effects of Building Direction, Process Parameters and Border Scanning on the Mechanical Properties of Laser Powder Bed Fusion AlSi10Mg
Authors: García-Zapata Juan M. , Torres Belén , Rams Joaquín
Published: July 2024

The variability arising from the LPBF process, the multitude of manufacturing parameters available, and the intrinsic anisotropy of the process, which causes different mechanical properties in distinct building directions, result in a wide range of variables that must be considered when designing industrial parts. To understand the effect of these variables on the LPBF manufacturing process, the performance of the AlSi10Mg alloy produced through this technique has been tested through several mechanical tests, including hardness, tensile, shear, and fracture toughness. The results have been correlated with the microstructure, together with manufacturing parameters, building directions, border scanning strategy, and layer height. Significant differences were observed for each mechanical behavior depending on the configuration tested. As a result, an anisotropic material model has been developed from tested samples, which allows to numerically model the alloy and is unique in the current literature.
Prediction of Welding Deformation Using the Thermal Elastic–Plastic Finite Element Method by Considering Welding Interpass Temperature
Authors: Han Young-Hwan , Lim Hun-Bong , Shin Tae-Sung , Yang Hyun-Ik
Published: July 2024

In this study, we propose a method for predicting welding deformation caused by multi-pass welding using the thermal elastic–plastic finite element method (TEP-FEM) by considering the interpass temperature. This method increases the interpass temperature, which has not been considered in the existing TEP-FEM, from 200 °C to 1000 °C, and simultaneously performs thermal and mechanical analyses. In addition, this method can also evaluate temperature history and the time it takes to weld. By predicting the welding deformation using this method, angular distortion prediction was reduced from 16.75 mm to 10.9 mm compared to the case where the interpass temperature was cooled to room temperature. Additionally, the deformation error was significantly reduced from 6.14% to 2.92% compared to that of the strain as directed boundary method used in a previous study. Additionally, our research demonstrated that interpass temperatures above 800 °C can result in increased deformation errors. In conclusion, it is essential to select an appropriate temperature to minimize deformation error.
A Review of an Investigation of the Ultrafast Laser Processing of Brittle and Hard Materials
Authors: Feng Jiecai , Wang Junzhe , Liu Hongfei , Sun Yanning , Fu Xuewen , Ji Shaozheng , Liao Yang , Tian Yingzhong
Published: July 2024

Ultrafast laser technology has moved from ultrafast to ultra-strong due to the development of chirped pulse amplification technology. Ultrafast laser technology, such as femtosecond lasers and picosecond lasers, has quickly become a flexible tool for processing brittle and hard materials and complex micro-components, which are widely used in and developed for medical, aerospace, semiconductor applications and so on. However, the mechanisms of the interaction between an ultrafast laser and brittle and hard materials are still unclear. Meanwhile, the ultrafast laser processing of these materials is still a challenge. Additionally, highly efficient and high-precision manufacturing using ultrafast lasers needs to be developed. This review is focused on the common challenges and current status of the ultrafast laser processing of brittle and hard materials, such as nickel-based superalloys, thermal barrier ceramics, diamond, silicon dioxide, and silicon carbide composites. Firstly, different materials are distinguished according to their bandgap width, thermal conductivity and other characteristics in order to reveal the absorption mechanism of the laser energy during the ultrafast laser processing of brittle and hard materials. Secondly, the mechanism of laser energy transfer and transformation is investigated by analyzing the interaction between the photons and the electrons and ions in laser-induced plasma, as well as the interaction with the continuum of the materials. Thirdly, the relationship between key parameters and ultrafast laser processing quality is discussed. Finally, the methods for achieving highly efficient and high-precision manufacturing of complex three-dimensional micro-components are explored in detail.
Study on the Compressive Strength and Reaction Mechanism of Alkali-Activated Geopolymer Materials Using Coal Gangue and Ground Granulated Blast Furnace Slag
Authors: Wang Xiaoping , Liu Feng , Li Lijuan , Chen Weizhi , Cong Xinhe , Yu Ting , Zhang Baifa
Published: July 2024

By reutilizing industrial byproducts, inorganic cementitious alkali-activated materials (AAMs) contribute to reduced energy consumption and carbon dioxide (CO2) emissions. In this study, coal gangue (CG) blended with ground granulated blast furnace slag (GGBFS) was used to prepare AAMs. The research focused on analyzing the effects of the GGBFS content and alkali activator (i.e., Na2O mass ratio and alkali modulus [SiO2/Na2O]) on the mechanical properties and microstructures of the AAMs. Through a series of spectroscopic and microscopic tests, the results showed that the GGBFS content had a significant influence on AAM compressive strength and paste fluidity; the optimal replacement of CG by GGBFS was 40–50%, and the optimal Na2O mass ratio and alkali modulus were 7% and 1.3, respectively. AAMs with a 50% GGBFS content exhibited a compact microstructure with a 28 d compressive strength of 54.59 MPa. Increasing the Na2O mass ratio from 6% to 8% promoted the hardening process and facilitated the formation of AAM gels; however, a 9% Na2O mass ratio inhibited the condensation of SiO4 and AlO4 ions, which decreased the compressive strength. Increasing the alkali modulus facilitated geopolymerization, which increased the compressive strength. Microscopic analysis showed that pore size and volume increased due to lower Na2O concentrations or alkali modulus. The results provide an experimental and theoretical basis for the large-scale utilization of AAMs in construction.
Investigation of High-Temperature Oxidation Behavior of Additive Manufactured CoCrMo Alloy for Mandrel Manufacturing
Authors: Toma Adina Cristina , Condruz Mihaela Raluca , Paraschiv Alexandru , Badea Teodor Adrian , Pătroi Delia , Popa Nicoleta Mirela
Published: July 2024

The cyclic oxidation behavior of an additive manufactured CoCrMo alloy with 0.14 wt.% C was investigated at 914 °C for 32 cycles, each lasting 10 h, resulting in a total exposure time of 320 h. The oxidation rate was assessed for mass gain after finishing each 40 h oxidation cycle. It was experimentally determined that the oxidative process at 914 °C of this CoCrMo alloy follows a parabolic law, with the process being fast at the beginning and slowing down after the first 40 h. The microstructural analysis revealed that in the as-printed state, the phases developed were primarily the γ matrix and minor traces of ε phase. The oxidative process ensured an increase in the ε phase and precipitation of carbides which produced a 12% increase in the material’s hardness after the first 40 h of exposure at 914 °C. The oxidation process led to the development of an oxide scale comprising a dense Cr2O3 layer and a porous layer of CoCr2O4 spinel, the latter spalling after the 240 h of exposure. Despite this spallation, the oxide scale continued to develop in the presence of O, Cr, and Co. The experimental analysis provided valuable insights regarding the material’s behavior under prolonged exposure at high temperature in air, demonstrating its suitability as a candidate for additive manufactured mandrels used for bending metallic pipe fitting elbows.