bluuebunny/crossref_metadata_2025 huggingface dataset:
Age-at-Death Estimation by Dental Means as a Part of the Skeletal Analysis
Authors: Adserias-Garriga Joe
Published: June 2023

Age-at-death is one of the most valuable pieces of information in a biological profile, and is an important step in identifying remains. Age-at-death estimation by dental means is performed by forensic odontologists and forensic anthropologists in their daily casework tasks. Both forensic odontologists and forensic anthropologists must be aware of all of the age indicators and of all of the methods that can offer the sufficient scientific robusticity that forensic cases require. Osteological and dental methods of age estimation rely on developmental changes in younger individuals and on degenerative changes in older individuals. Skeletal methods based on developmental changes are highly reliable, while methods based on degenerative or post-formation changes show higher variability. From all skeletal methods, those relying on tooth formation and development are the most accurate to assess an individual’s age. Dental methods of age estimation can be implemented in the skeletal analysis of juvenile and adult remains, representing an additional indicator of age. The aim of this review paper is to provide a practical reference for applying dental age estimation to human remains as a part of skeletal analysis.
Circuit Realization of the Fractional-Order Sprott K Chaotic System with Standard Components
Authors: Gokyildirim Abdullah
Published: June 2023

Interest in studies on fractional calculus and its applications has greatly increased in recent years. Fractional-order analysis has the potential to enhance the dynamic structure of chaotic systems. This study presents the implementation of a lower-order fractional electronic circuit using standard components for the Sprott K system. To our knowledge, there are no chaotic circuit realizations in the literature where the value of a fractional-order parameter is approximately 0.8, making this study pioneering in this aspect. Additionally, various numerical analyses of the system are conducted, including chaotic time series and phase planes, Lyapunov exponents, spectral entropy (SE), and bifurcation diagrams, in order to examine its dynamic characteristics and complexity. As anticipated, the voltage outputs obtained from the oscilloscope demonstrated good agreement with both the numerical analysis and PSpice simulations.
DNA Ancestry Testing and Racial Discourse in Higher Education: How the (Re)Biologization of Race (Un)Settles Monoracialism for Graduate Students
Authors: Mohajeri Orkideh , Johnston-Guerrero Marc P. , Foeman Anita , Lawton Bessie
Published: June 2023

The recent proliferation of DNA testing in both popular culture and higher education calls to question whether such testing reifies race as a biological construct and, in particular, whether or not it disrupts or reinforces monoracial categorizations. Graduate students, who are often at a point in their educational journeys to further question and critique commonly held ideas, provide a unique lens through which to investigate discourses surrounding DNA testing. In this qualitative study, we analyze data from four focus groups with 22 racially diverse U.S. graduate students who had recently completed an ancestry test. We identify two specific discourses that graduate student participants engaged in, including (a) a biological race discourse and (b) an agentic choice discourse. Together, these discourses produced distinct unsettled subjectivities for Black and White participants. Our findings suggest the need to more critically consider the usage of DNA ancestry testing in and out of higher education and to provide further nuance around the validity of these tests as they relate to the social construction of race.
Psychosocial Risks among Quebec Healthcare Workers during the COVID-19 Pandemic: A Social Media Analysis
Authors: Vivion Maryline , Jauvin Nathalie , Nicolakakis Nektaria , Pelletier Mariève , Letellier Marie-Claude , Biron Caroline
Published: June 2023

During the COVID-19 pandemic, healthcare workers (HCWs) were at high risk of exposure to the SARS-CoV-2 virus and to work-related psychosocial risks, such as high psychological demands, low social support at work and low recognition. Because these factors are known to be detrimental to health, their detection and mitigation was essential to protect the healthcare workforce during the pandemic, when this study was initiated. Therefore, using Facebook monitoring, this study aims to identify the psychosocial risk factors to which HCWs in Quebec, Canada reported being exposed at work during the first and second pandemic waves. In this study, HCWs mainly refer to nurses, respiratory therapists, beneficiary attendants and technicians (doctors, managers and heads of healthcare establishments were deemed to be less likely to have expressed work-related concerns on the social media platforms explored). A qualitative exploratory research based on passive analysis of Facebook pages from three different unions was conducted. For each Facebook page, automatic data extraction was followed by and completed through manual extraction. Posts and comments were submitted to undergo thematic content analysis allowing main coded themes to emerge based on known theoretical frameworks of the psychosocial work environment. In total, 3796 Facebook posts and comments were analyzed. HCWs reported a variety of psychosocial work exposures, the most recurrent of which were high workload (including high emotional demands), lack of recognition and perceived injustice, followed by low workplace social support and work–life conflicts. Social media monitoring was a useful approach for documenting the psychosocial work environment during the COVID-19 crisis and could be a useful means of identifying potential targets for preventive interventions in future sanitary crises or in a context of major reforms or restructuring.
Evaluating the Diagnostic Performance of Hemoglobin in the Diagnosis of Iron Deficiency Anemia in High-Altitude Populations: A Scoping Review
Authors: Vásquez-Velásquez Cinthya , Fernandez-Guzman Daniel , Quispe-Vicuña Carlos , Caira-Chuquineyra Brenda , Ccami-Bernal Fabricio , Castillo-Gutierrez Piero , Arredondo-Nontol Miriam , Gonzales Gustavo F.
Published: June 2023

We evaluated the available literature on the diagnostic performance of hemoglobin (Hb) in the diagnosis of iron deficiency anemia (IDA) in high-altitude populations. We searched PubMed, Web of Science, Scopus, Embase, Medline by Ovid, the Cochrane Library, and LILCAS until 3 May 2022. We included studies that evaluated the diagnostic performance (sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), receiver operating characteristic (ROC) curves, and accuracy) of Hb (with and without an altitude correction factor) compared to any iron deficiency (ID) marker (e.g., ferritin, soluble transferrin receptor (sTFR), transferrin saturation, or total body iron (TBI)) in populations residing at altitudes (≥1000 m above sea level). We identified a total of 14 studies (with 4522 participants). We found disagreement in diagnostic performance test values between the studies, both in those comparing hemoglobin with and in those comparing hemoglobin without a correction factor for altitude. Sensitivity ranged from 7% to 100%, whereas specificity ranged from 30% to 100%. Three studies reported higher accuracy of uncorrected versus altitude-corrected hemoglobin. Similarly, two studies found that not correcting hemoglobin for altitude improved the receiver operating characteristic (ROC) curves for the diagnosis of iron deficiency anemia. Available studies on high-altitude populations suggest that the diagnostic accuracy of Hb is higher when altitude correction is not used. In addition, the high prevalence of anemia in altitude regions could be due to diagnostic misclassification.
Perceived Barriers to Providing Spiritual Care in Palliative Care among Professionals: A Portuguese Cross-Sectional Study
Authors: Laranjeira Carlos , Dixe Maria Anjos , Querido Ana
Published: June 2023

Spiritual care is an important dimension of palliative care (PC) and a facet of holistic care that helps ill people find meaning in their suffering and lives. This study aims to: (a) develop and test the psychometric properties of a new instrument, Perceived Barriers to Spiritual Care (PBSC); (b) explore participants’ perceptions of how prevalent those (pre-identified) barriers are; and (c) examine the association of their personal and professional characteristics with those perceptions. A descriptive cross-sectional study was carried out using a self-reporting online survey. In total, 251 professionals registered with the Portuguese Association of Palliative Care (APCP) completed the study. The majority of respondents were female (83.3%), nurses (45.4%), had more than 11 years of professional experience (66.1%), did not work in PC (61.8%), and had a religious affiliation (81.7%). The psychometric assessment using PBSC provided sound evidence for its validity and reliability. The three most common perceived barriers were late referral for palliative care (78.1%), work overload (75.3%), and uncontrolled physical symptoms (72.5%). The least commonly perceived barriers were different spiritual beliefs among professionals (10.8%), differences between the beliefs of professionals and patients (14.4%), and the shame of approaching spirituality in a professional context (26.7%). The findings show there is some relationship between sex, age, years of professional experience, working in PC, having a religious affiliation, the importance of spiritual/religious beliefs, and responses to the PBSC tool. The results highlight the importance of advanced training in spirituality and intervention strategies. Further research is needed to properly study the impacts of spiritual care and establish outcome assessments that accurately reflect the effects of the various spiritual care activities.
Novel Model of Oxalate Diet-Induced Chronic Kidney Disease in Dahl-Salt-Sensitive Rats
Authors: Dube Prabhatchandra , Aradhyula Vaishnavi , Lad Apurva , Khalaf Fatimah K. , Breidenbach Joshua D. , Kashaboina Eshita , Gorthi Snigdha , Varatharajan Shangari , Stevens Travis W. , Connolly Jacob A. , Soehnlen Sophia M. , Sood Ambika , Marellapudi Amulya , Ranabothu Meghana , Kleinhenz Andrew L. , Domenig Oliver , Dworkin Lance D. , Malhotra Deepak , Haller Steven T. , Kennedy David J.
Published: June 2023

Diet-induced models of chronic kidney disease (CKD) offer several advantages, including clinical relevance and animal welfare, compared with surgical models. Oxalate is a plant-based, terminal toxic metabolite that is eliminated by the kidneys through glomerular filtration and tubular secretion. An increased load of dietary oxalate leads to supersaturation, calcium oxalate crystal formation, renal tubular obstruction, and eventually CKD. Dahl-Salt-Sensitive (SS) rats are a common strain used to study hypertensive renal disease; however, the characterization of other diet-induced models on this background would allow for comparative studies of CKD within the same strain. In the present study, we hypothesized that SS rats on a low-salt, oxalate rich diet would have increased renal injury and serve as novel, clinically relevant and reproducible CKD rat models. Ten-week-old male SS rats were fed either 0.2% salt normal chow (SS-NC) or a 0.2% salt diet containing 0.67% sodium oxalate (SS-OX) for five weeks.Real-time PCR demonstrated an increased expression of inflammatory marker interleukin-6 (IL-6) (p < 0.0001) and fibrotic marker Timp-1 metalloproteinase (p < 0.0001) in the renal cortex of SS-OX rat kidneys compared with SS-NC. The immunohistochemistry of kidney tissue demonstrated an increase in CD-68 levels, a marker of macrophage infiltration in SS-OX rats (p < 0.001). In addition, SS-OX rats displayed increased 24 h urinary protein excretion (UPE) (p < 0.01) as well as significant elevations in plasma Cystatin C (p < 0.01). Furthermore, the oxalate diet induced hypertension (p < 0.05). A renin–angiotensin–aldosterone system (RAAS) profiling (via liquid chromatography–mass spectrometry; LC–MS) in the SS-OX plasma showed significant (p < 0.05) increases in multiple RAAS metabolites including angiotensin (1–5), angiotensin (1–7), and aldosterone. The oxalate diet induces significant renal inflammation, fibrosis, and renal dysfunction as well as RAAS activation and hypertension in SS rats compared with a normal chow diet. This study introduces a novel diet-induced model to study hypertension and CKD that is more clinically translatable and reproducible than the currently available models.
RNA Biomarkers in Bipolar Disorder and Response to Mood Stabilizers
Authors: Pisanu Claudia , Squassina Alessio
Published: June 2023

Bipolar disorder (BD) is a severe chronic disorder that represents one of the main causes of disability among young people. To date, no reliable biomarkers are available to inform the diagnosis of BD or clinical response to pharmacological treatment. Studies focused on coding and noncoding transcripts may provide information complementary to genome-wide association studies, allowing to correlate the dynamic evolution of different types of RNAs based on specific cell types and developmental stage with disease development or clinical course. In this narrative review, we summarize findings from human studies that evaluated the potential utility of messenger RNAs and noncoding transcripts, such as microRNAs, circular RNAs and long noncoding RNAs, as peripheral markers of BD and/or response to lithium and other mood stabilizers. The majority of available studies investigated specific targets or pathways, with large heterogeneity in the included type of cells or biofluids. However, a growing number of studies are using hypothesis-free designs, with some studies also integrating data on coding and noncoding RNAs measured in the same participants. Finally, studies conducted in neurons derived from induced-pluripotent stem cells or in brain organoids provide promising preliminary findings supporting the power and utility of these cellular models to investigate the molecular determinants of BD and clinical response.
Effects of Diabetes Mellitus-Related Dysglycemia on the Functions of Blood–Brain Barrier and the Risk of Dementia
Authors: Wątroba Mateusz , Grabowska Anna D. , Szukiewicz Dariusz
Published: June 2023

Diabetes mellitus is one of the most common metabolic diseases worldwide, and its long-term complications include neuropathy, referring both to the peripheral and to the central nervous system. Detrimental effects of dysglycemia, especially hyperglycemia, on the structure and function of the blood–brain barrier (BBB), seem to be a significant backgrounds of diabetic neuropathy pertaining to the central nervous system (CNS). Effects of hyperglycemia, including excessive glucose influx to insulin-independent cells, may induce oxidative stress and secondary innate immunity dependent inflammatory response, which can damage cells within the CNS, thus promoting neurodegeneration and dementia. Advanced glycation end products (AGE) may exert similar, pro-inflammatory effects through activating receptors for advanced glycation end products (RAGE), as well as some pattern-recognition receptors (PRR). Moreover, long-term hyperglycemia can promote brain insulin resistance, which may in turn promote Aβ aggregate accumulation and tau hyperphosphorylation. This review is focused on a detailed analysis of the effects mentioned above towards the CNS, with special regard to mechanisms taking part in the pathogenesis of central long-term complications of diabetes mellitus initiated by the loss of BBB integrity.
Oxygen Nanocarriers for Improving Cardioplegic Solution Performance: Physico-Chemical Characterization
Authors: Tannous Maria , Hoti Gjylije , Trotta Francesco , Cavalli Roberta , Higashiyama Takanobu , Pagliaro Pasquale , Penna Claudia
Published: June 2023

Nanocarriers for oxygen delivery have been the focus of extensive research to ameliorate the therapeutic effects of current anti-cancer treatments and in the organ transplant field. In the latter application, the use of oxygenated cardioplegic solution (CS) during cardiac arrest is certainly beneficial, and fully oxygenated crystalloid solutions may be excellent means of myocardial protection, albeit for a limited time. Therefore, to overcome this drawback, oxygenated nanosponges (NSs) that can store and slowly release oxygen over a controlled period have been chosen as nanocarriers to enhance the functionality of cardioplegic solutions. Different components can be used to prepare nanocarrier formulations for saturated oxygen delivery, and these include native α-cyclodextrin (αCD), αcyclodextrin-based nanosponges (αCD-NSs), native cyclic nigerosyl-nigerose (CNN), and cyclic nigerosyl-nigerose-based nanosponges (CNN-NSs). Oxygen release kinetics varied depending on the nanocarrier used, demonstrating higher oxygen release after 24 h for NSs than the native αCD and CNN. CNN-NSs presented the highest oxygen concentration (8.57 mg/L) in the National Institutes of Health (NIH) CS recorded at 37 °C for 12 h. The NSs retained more oxygen at 1.30 g/L than 0.13 g/L. These nanocarriers have considerable versatility and the ability to store oxygen and prolong the amount of time that the heart remains in hypothermic CS. The physicochemical characterization presents a promising oxygen-carrier formulation that can prolong the release of oxygen at low temperatures. This can make the nanocarriers suitable for the storage of hearts during the explant and transport procedure.
Targeting Adenosine Signalling in Knee Chondropathy: The Combined Action of Polydeoxyribonucleotide and Pulsed Electromagnetic Fields: A Current Concept Review
Authors: Moretti Lorenzo , Bizzoca Davide , Geronimo Alessandro , Abbaticchio Andrea Michele , Moretti Francesco Luca , Carlet Arianna , Fischetti Francesco , Moretti Biagio
Published: June 2023

Chondropathy of the knee is one of the most frequent degenerative cartilage pathologies with advancing age. Scientific research has, in recent years, advanced new therapies that target adenosine A2 receptors, which play a significant role in human health against many disease states by activating different protective effects against cell sufferance and damage. Among these, it has been observed that intra-articular injections of polydeoxyribonucleotides (PDRN) and Pulsed Electromagnetic Fields (PEMF) can stimulate the adenosine signal, with significant regenerative and healing effects. This review aims to depict the role and therapeutic modulation of A2A receptors in knee chondropathy. Sixty articles aimed at providing data for our study were included in this review. The present paper highlights how intra-articular injections of PDRN create beneficial effects by reducing pain and improving functional clinical scores, thanks to their anti-inflammatory action and the important healing and regenerating power of the stimulation of cell growth, production of collagen, and the extracellular matrix. PEMF therapy is a valid option in the conservative treatment of different articular pathologies, including early OA, patellofemoral pain syndrome, spontaneous osteonecrosis of the knee (SONK), and in athletes. PEMF could also be used as a supporting therapy after an arthroscopic knee procedure total knee arthroplasty to reduce the post-operative inflammatory state. The proposal of new therapeutic approaches capable of targeting the adenosine signal, such as the intra-articular injection of PDRN and the use of PEMF, has shown excellent beneficial results compared to conventional treatments. These are presented as an extra weapon in the fight against knee chondropathy.
Cdk4 Regulates Glioblastoma Cell Invasion and Stemness and Is Target of a Notch Inhibitor Plus Resveratrol Combined Treatment
Authors: Giordano Francesca , D’Amico Maria , Montalto Francesca Ida , Malivindi Rocco , Chimento Adele , Conforti Francesca Luisa , Pezzi Vincenzo , Panno Maria Luisa , Andò Sebastiano , De Amicis Francesca
Published: June 2023

Glioblastoma multiforme (GBM) is one of the most aggressive types of cancer characterized by poor patient outcomes. To date, it is believed that the major cause of its recurrence and chemoresistance is represented by the enrichment of GBM stem cells (GSCs) sustained by the abnormal activation of a number of signaling pathways. In this study, we found that in GBM cells, treatment with low toxicity doses of the γ-secretase inhibitor RO4929097 (GSI), blocking the Notch pathway activity, in combination with resveratrol (RSV) was able to reverse the basal mesenchymal phenotype to an epithelial-like phenotype, affecting invasion and stemness interplay. The mechanism was dependent on cyclin D1 and cyclin-dependent kinase (CDK4), leading to a reduction of paxillin (Pxn) phosphorylation. Consequently, we discovered the reduced interaction of Pxn with vinculin (Vcl), which, during cell migration, transmits the intracellular forces to the extracellular matrix. The exogenous expression of a constitutively active Cdk4 mutant prevented the RSV + GSI inhibitory effects in GBM cell motility/invasion and augmented the expression of stemness-specific markers, as well as the neurosphere sizes/forming abilities in untreated cells. In conclusion, we propose that Cdk4 is an important regulator of GBM stem-like phenotypes and invasive capacity, highlighting how the combined treatment of Notch inhibitors and RSV could be prospectively implemented in the novel therapeutic strategies to target Cdk4 for these aggressive brain tumors.
Plants as the Extended Phenotype of Endophytes—The Actual Source of Bioactive Compounds
Authors: Rutkowska Natalia , Drożdżyński Piotr , Ryngajłło Małgorzata , Marchut-Mikołajczyk Olga
Published: June 2023

For thousands of years, plants have been used for their medicinal properties. The industrial production of plant-beneficial compounds is facing many drawbacks, such as seasonal dependence and troublesome extraction and purification processes, which have led to many species being on the edge of extinction. As the demand for compounds applicable to, e.g., cancer treatment, is still growing, there is a need to develop sustainable production processes. The industrial potential of the endophytic microorganisms residing within plant tissues is undeniable, as they are often able to produce, in vitro, similar to or even the same compounds as their hosts. The peculiar conditions of the endophytic lifestyle raise questions about the molecular background of the biosynthesis of these bioactive compounds in planta, and the actual producer, whether it is the plant itself or its residents. Extending this knowledge is crucial to overcoming the current limitations in the implementation of endophytes for larger-scale production. In this review, we focus on the possible routes of the synthesis of host-specific compounds in planta by their endophytes.
The Recurring Word in the Scientific Articles about the Role of Mg in Living Systems Is “Key”
Authors: Maier Jeanette A. , Iotti Stefano
Published: June 2023

Magnesium (Mg) is a versatile element involved in all aspects of life on our planet [...]
Activity of FAAH-Inhibitor JZP327A in an Experimental Rat Model of Migraine
Authors: Greco Rosaria , Francavilla Miriam , Demartini Chiara , Zanaboni Anna Maria , Facchetti Sara , Palmisani Michela , Franco Valentina , Tassorelli Cristina
Published: June 2023

Increased anandamide levels via fatty acid amide hydrolase (FAAH) inhibition can decrease the pronociceptive responses and inflammatory mediators in animal models of migraine. Here, we profile the pharmacological activity of the FAAH inhibitor JZP327A, a chiral 1,3,4-oxadiazol-2(3H)-one compound, in the mediation of spontaneous and nocifensive behaviour in the animal models of migraine based on nitroglycerin (NTG) administration. JZP327A (0.5 mg/kg, i.p.) or vehicle was administered to male rats 3 h after NTG (10 mg/kg, i.p.) or NTG vehicle injection. The rats were then exposed to the open field test and an orofacial formalin test 1 h later. The levels of endocannabinoids and lipid-related substances, and the expression of pain and inflammatory mediators were evaluated in cranial tissues and serum. The findings show that JZP327A did not affect NTG-induced changes in the spontaneous behaviour of rats, while it inhibited NTG-induced hyperalgesia at the orofacial formalin test. Furthermore, JZP327A dramatically decreased the gene expression of calcitonin gene-related peptide (CGRP), tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) in the trigeminal ganglia and medulla-pons, while it did not change endocannabinoids or lipids levels nor CGRP serum levels in the same tissues. These data suggest an anti-hyperalgesic role for JZP327A in the NTG model, which is mediated by the inhibition of the inflammatory cascade of events. This activity does not seem mediated by a change in the levels of endocannabinoids and lipid amides.
Artful Ageing, Not Just Successful Ageing
Authors: Fristrup Tine , Rasmussen Jon Dag
Published: June 2023

In this article, we develop a tentative philosophy to orchestrate and support possibilities for artful ageing. This effort argues that older adults need a broader range of opportunities to explore the manifold ephemeral, non-rational, and in-between elements of an ageing life. The philosophy is rooted in the notion that older adults need space (literally and metaphorically) to explore and process their existence and that engaging in such processes can entail emancipatory effects in everyday life. The perspective unfolded throughout the article is a philosophical venture, or, rather, a preliminary work, developing the concept of artful ageing as a tool applicable in rethinking and broadening the range of activities occurring in institutional settings dedicated to older adults. Furthermore, the perspective also presents a critical stance towards normative footings and biopolitical agendas embedded in current regimes of active ageing. Artful ageing represents the ambition to enable and support artful lives, events, and activities among residents and participants in care homes and other contexts. We argue that physical and existential spaces are closely intertwined entities and that initiatives aimed at maintaining adequate measures of openness, ambiguity, and sensory intimacy, i.e., events that allow for the experience of metaphorical cracks, can afford artful pockets in which to reside for a while, seek refuge, recharge, stray from the beaten track, and obtain an always partial feeling of emancipation. In qualifying the concept of artful ageing, we hope to open new avenues to contemplate and subsequently initiate activities for older adults that are not just orientated towards physical health in later life. At the same time, our ambition is to develop a critical perspective aimed at challenging existing notions of successful ageing in (re)invigorating the importance of artful processes and experiences as an element inherent to successful ageing, as well.
Fans, Fellows or Followers: A Study on How Sport Federations Shape Social Media Affordances
Authors: Broms Lovisa
Published: June 2023

Increased in-depth knowledge on how sport federations shape their social media affordances to build relationships with their audiences will develop the understanding and ongoing discussion on the effects of social media in organized sports. The aim of this study was therefore to investigate in what way sports federations shape their social media affordances to create an increased understanding of how they interact with their audiences through social media. Three sports federations, the Swedish Basketball Federation, the Swedish Skateboard Association, and the Swedish Equestrian Federation, were investigated through semi-structured interviews as well as digital ethnography. The analytical focus lies on in what way the organizations shape social media affordances as well as in what way they imagine social media uses and users. This study shows that the federations’ imagination of who their users are, what they would like to see and how these users act and react defines their affordances. Further, the results reveal that the federations have differing approaches to in what way they imagine their users (as fans, fellows or followers) as well as what their incentives are for using social media. To learn how ongoing mediations mold long-term changes for sport federations, it is of importance to look beyond mediatization and learn more about their current structure and operations, their history, and traditions, as well as their view of their users.
Development and Preliminary Application of Temperature Stress Test Machine for Cast-in-Place Inner Shaft Lining
Authors: Zhang Chi , Wang Shuaishuai , Zhang Tao , Li Dahai , Chen Hairui
Published: June 2023

Over the past 20 years, as the depth and diameter of shaft lines increased in China, the cracking and water leakage of the inner walls of frozen shafts have become increasingly severe, resulting in significant safety threats and economic losses. Understanding the stress variation patterns of cast-in-place inner walls under the combined effects of temperature and constraint during construction is a prerequisite for evaluating the crack resistance performance of inner walls and preventing water leakage in frozen shafts. The temperature stress testing machine is an important instrument for studying the early-age crack resistance performance of concrete materials under the combined effects of temperature and constraint. However, existing testing machines have shortcomings in terms of applicable specimen cross-sectional shapes, temperature control methods for concrete structures, and axial loading capacity. In this paper, a novel temperature stress testing machine suitable for the inner wall structure shape, capable of simulating the hydration heat of the inner walls, was developed. Then, a reduced-scale model of the inner wall according to similarity criteria was manufactured indoors. Finally, preliminary investigations of the temperature, strain, and stress variations of the inner wall under 100% end constraint conditions were conducted by simulating the actual hydration heating and cooling process of the inner walls. Results show that the hydration heating and cooling process of the inner wall can be accurately simulated. After approximately 69 h of concrete casting, the accumulated relative displacement and strain of the end-constrained inner wall model were −244.2 mm and 187.8 με, respectively. The end constraint force of the model increased to a maximum value of 1.7 MPa and then rapidly unloaded, causing the model concrete to crack in tension. The temperature stress testing method presented in this paper provides a reference for scientifically formulating technical approaches to prevent cracking in cast-in-place concrete inner walls.
High-Index Epitaxial Fe Films Grown on MgO(113)
Authors: Peng Wenzhi , Chen Yulong , Yu Xuhao , Hou Dazhi
Published: June 2023

The epitaxial growth of high-index Fe films on MgO(113) substrates is successfully achieved using direct current (DC) magnetron sputtering, despite the significant lattice constant mismatch between Fe and MgO. X-ray diffraction (XRD) analysis is employed to characterize the crystal structure of Fe films, revealing an Fe(103) out-of-plane orientation. Furthermore, our investigation reveals that the Fe[010] direction is parallel to the MgO[11¯0] direction within the films plane. These findings provide valuable insights into the growth of high-index epitaxial films on substrates with large lattice constant mismatch, thereby contributing to the advancement of research in this field.
Efficient Lithium-Based Upconversion Nanoparticles for Single-Particle Imaging and Temperature Sensing
Authors: Alzahrani Yahya A. , Alromaeh Abdulaziz , Alkahtani Masfer
Published: June 2023

Upconversion Nanoparticles (UCNPs) have attracted exceptional attention due to their great potential in high-contrast, free-background biofluorescence deep tissue imaging and quantum sensing. Most of these interesting studies have been performed using an ensemble of UCNPs as fluorescent probes in bioapplications. Here, we report a synthesis of small and efficient YLiF4:Yb,Er UCNPs for single-particle imaging as well as sensitive optical temperature sensing. The reported particles demonstrated a bright and photostable upconversion emission at a single particle level under a low laser intensity excitation of 20 W/cm2. Furthermore, the synthesized UCNPs were tested and compared to the commonly used two-photon excitation QDs and organic dyes and showed a nine times better performance at a single particle level under the same experimental conditions. In addition, the synthesized UCNPs demonstrated sensitive optical temperature sensing at a single particle level within the biological temperature range. The good optical properties of single YLiF4:Yb,Er UCNPs open an avenue for small and efficient fluorescent markers in imaging and sensing applications.
Numerical Study on Mechanical Responses during Quench Protection in High-Temperature Superconducting Coils
Authors: Jiao Ruoshan , Guan Mingzhi
Published: June 2023

In this paper, mechanical responses and electro-thermal characteristics of a rare earth barium copper oxide (REBCO) high-temperature superconducting (HTS) insulated pancake coil during the quenching process are investigated through finite element modeling (FEM). Firstly, a two-dimensional axisymmetric electro–magneto–thermal–mechanical FEM model with real dimensions is developed. Based on the FEM model, a systematic study on the effects of the time taken to trigger the system dump, background magnetic field, material properties of constituent layers, and coil size on quench behaviors of an HTS-insulated pancake coil is implemented. The variations in the temperature, current, and stress–strain in the REBCO pancake coil are studied. The results indicate that an increase in the time taken to trigger the system dump can increase the peak temperature of the hot spot but has no influence on the dissipation velocity. An apparent slope change of the radial strain rate is observed when the quench occurs regardless of the background field. During quench protection, the radial stress and strain reach their maximum values and then decrease as the temperature decreases. The axial background magnetic field has a significant influence on the radial stress. Measures to reduce peak stress and strain are also discussed, which indicates that increasing the thermal conductivity of the insulation layer, copper thickness, and inner coil radius can effectively reduce the radial stress and strain.
MnPc Films Deposited by Ultrasonic Spray Pyrolysis at Low Temperatures: Optical, Morphological and Structural Properties
Authors: Luna Zempoalteca Anayantzi , Hernández de la Luz José Álvaro David , Luna Flores Adan , Luna López José Alberto , Benítez Lara Alfredo
Published: June 2023

In this work, we report how manganese phthalocyanine (MnPc) films obtained using the ultrasonic spray–pyrolysis technique at 40 °C deposited on glass substrate subjected to thermal annealing at 100 °C and 120 °C. The MnPc films were characterized using UV/Vis spectroscopy, Raman spectroscopy, X-Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM). The absorption spectra of the MnPc films were studied in a wavelength range from 200 to 850 nm, where the characteristic bands of a metallic phthalocyanine known as B and Q bands were observed in this range of the spectrum. The optical energy band (Eg) was calculated using the Tauc equation. It was found that, for these MnPc films, the Eg has the values of 4.41, 4.46, and 3.58 eV corresponded to when they were deposited, annealing at 100 °C and 120 °C, respectively. The Raman spectra of the films showed the characteristic vibrational modes of the MnPc films. In the X-Ray diffractograms of these films, the characteristic diffraction peaks of a metallic phthalocyanine are observed, presenting a monoclinic phase. The SEM images of these films were studied in a cross-section obtaining thicknesses of 2 μm for the deposited film and 1.2 μm and 0.3 μm for the annealed films at 100 °C and 120 °C. Additionally, in the SEM images of these films, average particle sizes ranging from 4 to 0.041 µm were obtained. The results agree with those reported in the literature for MnPc films deposited by performing other techniques.
Effect of Artificial Aging Treatment on the Mechanical Properties and Regulation of Precipitated Phase Particles of High-Pressure Die-Cast Thin-Wall AlSi10MnMg Longitudinal Carrier
Authors: Zhao Xu , Wang Ping , Yang Yang , Wang Song , Zhao Qiang , Sun Jingying
Published: June 2023

This study investigates the artificial aging treatment process for AlSi10MnMg longitudinal carriers with optimal strength and ductility. Experimental results illustrate that the peak strength is observed under single-stage aging at 180 °C × 3 h, with a tensile strength of 332.5 MPa, Brinell hardness of 133.0 HB, and elongation of 5.56%. As aging time increases, tensile strength and hardness initially increase and then decrease, while elongation displays an inverse pattern. The amount of secondary phase particles at grain boundaries increases with aging temperature and holding time, but stabilizes as aging progresses; the secondary phase particles begin to grow, eventually weakening the alloy’s strengthening effect. The fracture surface exhibits mixed fracture characteristics, including ductile dimples and brittle cleavage steps. Range analysis indicates that the influence of distinct parameters on mechanical properties post-double-stage aging is as follows: first-stage aging time, first-stage aging temperature, followed again by second-stage aging time, and second-stage aging temperature. For peak strength, the optimal double-stage aging process includes a first-stage aging temperature of 100 °C × 3 h and a second-stage aging temperature of 180 °C × 3 h.
Interlayer Tailoring of Ti–6Al–4V and 17-4PH Stainless Steel Joint by Tungsten Inert Gas Welding
Authors: Hajra Raj Narayan , Park Chan Woong , Choi Kyunsuk , Kim Jeoung Han
Published: June 2023

The development of robust and efficient methods for constructing and joining complex metal specimens with high bonding quality and durability is of paramount importance for various industries, e.g., aerospace, deep space, and automobiles. This study investigated the fabrication and characterization of two types of multilayered specimens prepared by tungsten inert gas (TIG) welding: Ti–6Al–4V/V/Cu/Monel400/17-4PH (Specimen 1) and Ti–6Al–4V/Nb/Ni–Ti/Ni–Cr/17-4PH (Specimen 2). The specimens were fabricated by depositing individual layers of each material onto a Ti–6Al–4V base plate, and subsequently welding them to the 17-4PH steel. The specimens exhibited an effective internal bonding without any cracks, accompanied by a high tensile strength, with Specimen 1 exhibiting a significantly higher tensile strength than Specimen 2. However, the substantial interlayer penetration of Fe and Ni in the Cu and Monel layers of Specimen 1 and the diffusion of Ti along the Nb and Ni–Ti layers in Specimen 2 resulted in a nonuniform elemental distribution, raising concerns about the lamination quality. This study successfully achieved elemental separation of Fe/Ti and V/Fe, which is vital for preventing the formation of detrimental intermetallic compounds, particularly in the fabrication of complex multilayered specimens, representing the prime novelty of this work. Our study highlights the potential of TIG welding for the fabrication of complex specimens with high bonding quality and durability.
Design of Ti64/Ta Hybrid Materials by Powder Metallurgy Mimicking Bone Structure
Authors: Alvarado-Hernández Francisco , Mihalcea Elena , Jimenez Omar , Macías Rogelio , Olmos Luis , López-Baltazar Enrique A. , Guevara-Martinez Santiago , Lemus-Ruiz José
Published: June 2023

This work reports on the fabrication of a novel two-layer material composed of a porous tantalum core and a dense Ti6Al4V (Ti64) shell by powder metallurgy. The porous core was obtained by mixing Ta particles and salt space-holders to create large pores, the green compact was obtained by pressing. The sintering behavior of the two-layer sample was studied by dilatometry. The interface bonding between the Ti64 and Ta layers was analyzed by SEM, and the pore characteristics were analyzed by computed microtomography. Images showed that two distinct layers were obtained with a bonding achieved by the solid-state diffusion of Ta particles into Ti64 during sintering. The formation of β-Ti and α′ martensitic phases confirmed the diffusion of Ta. The pore size distribution was in the size range of 80 to 500 µm, and a permeability value of 6 × 10−10 m2 was close to the trabecular bones one. The mechanical properties of the component were dominated mainly by the porous layer, and Young’s modulus of 16 GPa was in the range of bones. Additionally, the density of this material (6 g/cm3) was much lower than the one of pure Ta, which helps to reduce the weight for the desired applications. These results indicate that structurally hybridized materials, also known as composites, with specific property profiles can improve the response to osseointegration for bone implant applications.
Complex Monte Carlo Light-Driven Dynamics of Monomers in Functionalized Bond Fluctuation Model Polymer Chains
Authors: Pawlik Grzegorz , Mitus Antoni C.
Published: June 2023

We study Monte Carlo dynamics of the monomers and center of mass of a model polymer chain functionalized with azobenzene molecules in the presence of an inhomogeneous linearly polarized laser light. The simulations use a generalized Bond Fluctuation Model. The mean squared displacements of the monomers and the center of mass are analyzed in a period of Monte Carlo time typical for a build-up of Surface Relief Grating. Approximate scaling laws for mean squared displacements are found and interpreted in terms of sub- and superdiffusive dynamics for the monomers and center of mass. A counterintuitive effect is observed, where the monomers perform subdiffusive motion but the resulting motion of the center of mass is superdiffusive. This result disparages theoretical approaches based on an assumption that the dynamics of single monomers in a chain can be characterized in terms of independent identically distributed random variables.
Numerical Modeling of a Sustainable Solid-State Recycling of Aluminum Scraps by Means of Friction Stir Extrusion Process
Authors: Bocchi Sara , D’Urso Gianluca , Giardini Claudio
Published: June 2023

One of the most important purposes of the modern industry is a sustainable production, considering the minimization of the energy and of the raw materials used, together with the reduction of polluting emissions. In this context, Friction Stir Extrusion stands out, since it allows to obtain extrusions starting from metal scraps deriving from traditional mechanical machining processes (e.g., chips deriving from cutting operations), heated only by the friction generated between the scraps and the tool, so avoiding the material melting phase. Given the complexity of this new kind of process, the objective of this research is the study of the bonding conditions considering both the heat and the stresses generated during the process under different working parameters, namely tool rotational and descent speeds. As a result, the combined approach involving the Finite Element Analysis and the Piwnik and Plata criterion proves to be a valid tool for forecasting if bonding phenomenon occurs and how it is influenced by the process parameters. The results have also demonstrated that it is possible to achieve completely massive pieces between 500 rpm and 1200 rpm, but at different tool descent speeds. Specifically, up to 1.2 mm/s for 500 rpm and just over 2 mm/s for 1200 rpm.
Local Phase Segregation Induced by Ion Milling in 2:17-Type Sm-Co Based Magnets
Authors: Song Xin , Liu Yao , Jia Wentao , Li Jian , Liu Xiaolian , Zhao Lizhong , Yuan Tao , Ma Tianyu
Published: June 2023

Transmission electron microscopy (TEM) is indispensable to reveal the cellular nanostructure of the 2:17-type Sm-Co based magnets which act as the first choice for high-temperature magnet-associated devices. However, structural deficiencies could be introduced into the TEM specimen during the ion milling process, which would provide misleading information to understand the microstructure–property relationship of such magnets. In this work, we performed a comparative investigation of the microstructure and microchemistry between two TEM specimens prepared under different ion milling conditions in a model commercial magnet Sm13Gd12Co50Cu8.5Fe13Zr3.5 (wt.%). It is found that additional low-energy ion milling will preferably damage the 1:5H cell boundaries, while having no influence on the 2:17R cell phase. The structure of cell boundary transforms from hexagonal into face-centered-cubic. In addition, the elemental distribution within the damaged cell boundaries becomes discontinuous, segregating into Sm/Gd-rich and Fe/Co/Cu-rich portions. Our study suggested that in order to reveal the true microstructure of the Sm-Co based magnets, the TEM specimen should be carefully prepared to avoid structural damage and artificial deficiencies.
Multi-Person 2-D Positioning Method Based on 77 GHz FMCW Radar
Authors: Huang Xiaohong , Ju Zedong , Zhu Jikun , Zhang Rundong
Published: June 2023

As the world’s population ages, technologies that enable long-term non-contact monitoring of patients are of great research significance. For this purpose, we propose a multi-person 2-D positioning method based on a 77 GHz FMCW radar. In this method, we first perform beam scanning processing on the data cube acquired by the radar and obtain the distance–Doppler–angle data cube. Then, we eliminate interfering targets through a multi-channel respiratory spectrum superposition algorithm. Finally, we obtain the distance and angle information of the target by the target center selection method. The experimental results show that the proposed method can detect the distance and angle information of multiple people.
Vitamin B12—Multifaceted In Vivo Functions and In Vitro Applications
Authors: Halczuk Krzysztof , Kaźmierczak-Barańska Julia , Karwowski Bolesław T. , Karmańska Aleksandra , Cieślak Marcin
Published: June 2023

Vitamin B12 plays a key role in DNA stability. Research indicates that vitamin B12 deficiency leads to indirect DNA damage, and vitamin B12 supplementation may reverse this effect. Vitamin B12 acts as a cofactor for enzymes such as methionine synthase and methylmalonyl-CoA mutase, which are involved in DNA methylation and nucleotide synthesis. These processes are essential for DNA replication and transcription, and any impairment can result in genetic instability. In addition, vitamin B12 has antioxidant properties that help protect DNA from damage caused by reactive oxygen species. This protection is achieved by scavenging free radicals and reducing oxidative stress. In addition to their protective functions, cobalamins can also generate DNA-damaging radicals in vitro that can be useful in scientific research. Research is also being conducted on the use of vitamin B12 in medicine as vectors for xenobiotics. In summary, vitamin B12 is an essential micronutrient that plays a vital role in DNA stability. It acts as a cofactor for enzymes involved in the synthesis of nucleotides, has antioxidant properties and has potential value as a generator of DNA-damaging radicals and drug transporters.