bluuebunny/crossref_metadata_2025 huggingface dataset:
On the influence of vessel planarity on local hemodynamics at the human carotid bifurcation
Authors: Thomas Jonathan B. , Milner Jaques S. , Steinman David A.
Published: November 2024

The human carotid artery bifurcation is a complex, three‐dimensional structure exhibiting non‐planarity and both in‐ and out‐of‐plane curvature. The aim of this study was to determine the relative importance of vessel planarity, a potential geometric risk factor for atherogenesis, in determining the local hemodynamics. A combination of computational fluid dynamics and magnetic resonance imaging was used to reconstruct the subject‐specific hemodynamics for three subjects. Planar models were then constructed by translating the centroids of the lumen contours onto a plane defined by the centroids of the vessel branches near the bifurcation apex. A novel “patching” technique was used to convert the continuous arterial surfaces into contiguous but discrete patches according to an objective scheme, making it possible to compare the original and planar models without the need for registration and warping. Results suggest that the planarity of the vessel has a relatively minor effect on the spatial distribution of mean and oscillatory wall shear stress. Out‐of‐plane curvature was, however, found to have a marked influence on the extent and magnitude of these hemodynamic variables. We conclude that vessel curvature – whether in‐ or out‐of‐plane – rather than planarity may deserve further scrutiny as a potential geometric risk for atherogenesis.
Ultrasound techniques for measurement of blood flow and tissue motion
Authors: Hoskins P.R.
Published: November 2024

This article will review the ability of ultrasound techniques to provide 3D information on arterial geometry, blood flow and tissue motion.

3D systems. 3D datasets can be obtained by sequential acquisition of 2D slices. Ideally a transducer is required in which there is full control of beam steering within a 3D volume. This requires a 2D array consisting of several thousand elements. Prototype 2D arrays have been built which provide several 3D datasets per second.

Blood velocity measurement. Current Doppler systems estimate only the component of velocity in the direction of the Doppler beam. Lack of knowledge of the direction of blood motion and also other effects associated with ‘spectral broadening’ limit the accuracy of velocity measurement. Improved accuracy can be obtained using vector Doppler systems using 2 or 3 beam directions; this approach is referred to as ‘vector Doppler’.

Tissue motion. Doppler techniques can also be used to detect tissue motion (Tissue Doppler Imaging or TDI). Motion of the artery wall can be calculated from the TDI images. It is possible to estimate simultaneously motion for adjacent diameters within the longitudinal plane, and to visualise the relative motion at different parts of the wall.
A boundary layer model for wall shear stress in arterial stenosis
Authors: Provenzano Paolo P. , Rutland Christopher J.
Published: November 2024

This paper proposes a model for wall shear stress in arterial stenosis based on boundary layer theory. Wall shear stress estimates are obtained by solving the momentum integral equation using the method proposed by Walz and applying this method to various stenosis geometries for Reynolds numbers (Re) of Re=59–1000. Elevated wall shear stress may be of importance when considering thrombosis and vascular erosion in stenosis, as well as the potential for debris from the stenotic area to ‘break away’ and cause further pathology. The values of shear stress obtained using the model in this study agree well with published values of wall shear stress. When compared to a previously published boundary layer model utilizing the Thwaites method (Reese and Thompson, 1998), the model proposed herein performs better at higher Re while the model utilizing the Thwaites method performs better at lower Re. Wall shear stresses are shown to increase with increasing stenosis (increased area reduction) for a given stenosis length, increase with increasing Re for a given stenosis geometry, and increase for steeper stenosis of the same constriction. The boundary layer model proposed can be easily implemented by clinical researchers to provide in vivo estimates of wall shear stress through arterial stenoses.
Microarray analysis of shear stressed endothelial cells
Authors: McCormick Susan M. , Frye Stacie R. , Eskin Suzanne G. , Teng Christina L. , Lu Chiung‐Mei , Russell Christopher G. , Chittur Krishnan K. , McIntire Larry V.
Published: November 2024

The cDNA microarray is an extremely beneficial tool for study of differential gene expression in the cardiovascular system. This technique is used in many different applications including drug discovery, environmental science, and the effects of mechanical forces on vascular cell phenotype. The paper reviews work by others, and describes our study on effects of shear stress on vascular endothelial cells. These microarray studies verified earlier findings using Northern and polymerase chain reaction (PCR) analyses in this area; and also found previously unidentified differentially expressed genes, leading to new hypotheses regarding how cells and tissues respond to biochemical and mechanical stimuli.
The effect of cyclical compressive loading on gene expression in articular cartilage
Authors: Blain Emma J. , Mason Deborah J. , Duance Victor C.
Published: November 2024

Osteoarthritis (OA) develops as a consequence of articular cartilage degeneration possibly initiated by excessive or abnormal loading of the joint, and potentially mediated through a proteinase/proteinase inhibitor imbalance. We have shown previously that physiological loads (0.5 MPa, 1 Hz, 3 hour) elicit increased expression and activation of the matrix metalloproteinases (MMPs) in articular cartilage explants in vitro. The objective of this study was to identify mechanically‐regulated genes involved in the observed induction of MMP expression and enhanced activation. Differential RNA Display (DRD) was used to identify mechanically‐regulated genes by comparing DRD products derived from loaded and unloaded cartilage. One gene up‐regulated in cartilage after 10, 30 and 60 minute loading revealed 83% homology with Mus musculus thymosin β4 which is known to induce MMP gene expression. The identification of mechanically regulated genes will greatly enhance our understanding of matrix turnover providing an exciting future in elucidating the role of mechanically‐regulated genes in the development of OA.
Specific induction of heat shock protein 90 beta by high hydrostatic pressure
Authors: Elo Mika A. , Sironen Reijo K. , Karjalainen Hannu M. , Kaarniranta Kai , Helminen Heikki J. , Lammi Mikko J.
Published: November 2024

In chondrocytes, a low‐amplitude intermittent hydrostatic pressure induces production of extracellular matrix molecules, while high hydrostatic pressure inhibits it. High pressure increases cellular heat shock protein 70 level in a number of cell types on account of increased stabilisation of the heat shock protein 70 mRNA. In our experiments, only bovine primary chondrocytes, but not an immortalized chondrocytic cell line, could resist the induction of the stress response in the presence of continuous 30 MPa hydrostatic pressure. We have recently shown that protein synthesis is required for the stabilization. According to two‐dimensional gel electrophoresis the synthesis of heat shock protein 90 was also increased in a chondrocytic cell line and in HeLa cells, and mass spectrometric analysis suggested that the induction was rather due to increase in heat shock protein 90β than in heat shock protein 90α. The stress response was rather intense in HeLa cells, therefore, we investigated the effect of continuous 30 MPa hydrostatic pressure on the expression of the two heat shock protein 90 genes in HeLa cells using Northern and Western blot analyses. Heat shock protein 90β mRNA level increased within 6 hours of exposure to 30 MPa hydrostatic pressure, while hsp90α level remained stable. At protein level there was a clear increase in the heat shock protein 90β/heat shock protein 90α ratio, too. These results show a specific regulation of stress proteins in cells exposed to high hydrostatic pressure.
Formation and destruction of primary thrombi under the influence of blood flow and von Willebrand factor analyzed by a discrete element method
Authors: Miyazaki Hisako , Yamaguchi Takami
Published: November 2024

Thrombogenesis and thrombolysis processes were simulated using a computational mechanics method called the discrete element method (DEM) to model the mechanical interactions between blood flow, platelets, the vessel wall, and von Willebrand factor (vWf). The inclusion of vWf and a complex blood flow field in the DEM are new developments used in this study. A primary thrombus did not form in the simulations if only the axial fluid force was considered, even when vWf was activated to simulate an endothelial injury. When the radial fluid force was considered to include the exclusion effect of erythrocytes, the modeled platelets formed primary thrombi at lesions where vWf was present. This suggests that activation of vWf is not sufficient to promote the formation of primary thrombi; a complex flow field that facilitates the transport of platelets towards the wall is also required.
New information from cell aggregate compression tests and its implications for theories of cell sorting
Authors: Brodland G. Wayne
Published: November 2024

In order to verify theories about the mechanics of cell sorting, tissue spreading and checkerboard pattern formation, it is necessary to measure certain cell properties such as surface tension and adhesiveness. The purpose of this work is to clarify the relationship between these two important properties and to use computer simulations and analytical calculations to extract additional information from parallel plate compression tests. This paper shows that compression tests can be used to determine not only the surface tension between the aggregate and the surrounding medium, but also the effective viscosity of the cell cytoplasm and the interfacial tension that acts between the cells that make up the aggregate. The findings reported here also support a novel, differential interfacial tension‐based theory for cell sorting, tissue spreading and checkerboard pattern formation, and pose further challenges to current differential adhesion‐based models.
Spatial distribution of the β2 integrin (CD11b/CD18) and L‐selectin (CD62L) adherence receptors on human neutrophils by Conventional Optical Scanning Microscopy (COSM)
Authors: Latger‐Cannard Véronique , Dumas Dominique , Bensoussan Danièle , Stoltz Jean‐François
Published: November 2024

Receptors such as CD62L and CD11b/CD18, are transmembrane glycoproteins which regulate leukocyte adhesive phenotype. Flow cytometry (FCM) makes it possible to assess a characterization of the cell activation level by receptor quantifying, but that technique does not integrate other factors of adherence regulation, such as spatial distribution and molecular conformation. Our study consisted in exploring the main adherence receptors on Polymorphonuclear Neutrophils (PMN) that were simultaneously analyzed by FCM and Conventional Optical Scanning Microscopy (COSM). FCM analysis showed that TNFα induce a decrease in CD62L expression and an increase in β2 integrins. COSM analysis distinguished three stages of cellular distribution of CD11b/CD18 within resting PMN: most of them (about 80%) had homogeneous distribution (heterogeneous spots distributed over the entire cell surface), for 10–15% of the cells, there was a crown distribution around the widest cell diameter and in less that 10% of them receptor distribution was polarized. CD62L was in the form of heterogeneous spots distributed in a circle on the surface on non‐stimulated PMN. PMN stimulation by TNFα was associated to a randomized clustering involving both selectin and β2 integrin. Three‐dimensional analysis elicited data not shown by quantitative cytometry. For a single averaged value of the density determined by FMC, various spatial distributions of adherence receptors are found on the surface of non‐stimulated PMN. The characterization of the leukocyte adhesive phenotype has to integrate adherence receptors density as well as their spatial distribution.
Cyclic AMP‐dependent cell shape changes induced by mechanical forces
Authors: Chotard‐Ghodsnia R. , Drochon A. , Faucheux N. , Nagel M.‐D. , Grebe R.
Published: November 2024

Biomaterials used in some biomedical devices are exposed to flow of physiological fluids. The flow‐induced forces may influence the morphological and the biochemical responses of adhering cells. The objective of this work is to examine the capacity of a mechanical stress to cause changes in cell/substratum and cell/cell interactions via the second messenger cAMP pathway (cyclic Adenosine Monophosphate). Cyclic AMP is known to modulate cell shape, cell adhesion and intercellular communication in static conditions. A specially designed flow chamber was used to analyze the responses of mouse 3T3 fibroblasts spread on biocompatible substrata and submitted to controlled shear stresses. A 1.1‐Pa shear stress induced: cell rounding, disruption of vitronectin receptors clusters and clustering of connexins 43 at cell–cell apposition points. These cell responses were cAMP‐dependent. These investigations should help provide a better understanding of the early biochemical events triggered by mechanical forces.
In vitro models to study compressive strain‐induced muscle cell damage
Authors: Bouten Carlijn V.C. , Breuls Roel G.M. , Peeters Emiel A.G. , Oomens Cees W.J. , Baaijens Frank P.T.
Published: November 2024

Skeletal muscle tissue is highly susceptible to sustained compressive straining, eventually leading to tissue breakdown in the form of pressure sores. This breakdown begins at the cellular level and is believed to be triggered by sustained cell deformation. To study the relationship between compressive strain‐induced muscle cell deformation and damage, and to investigate the role of cell–cell interactions, cell–matrix interactions and tissue geometry in this process, in vitro models of single cells, monolayers and 3D tissue analogs under compression are being developed. Compression is induced using specially designed loading devices, while cell deformation is visualised with confocal microscopy. Cell damage is assessed from viability tests, vital microscopy and histological or biochemical analyses. Preliminary results from a 3D cell seeded agarose model indicate that cell deformation is indeed an important trigger for cell damage; sustained compression of the model at 20% strain results in a significant increase in cell damage with time of compression, whereas damage in unstrained controls remains constant over time.
The influence of hyperbaric oxygen on hemorheological parameters in diabetic rats
Authors: Liu Der‐Zen , Chien Shu‐Chen , Tseng Li‐Ping , Yang Charng‐Bin
Published: November 2024

The effect of hyperbaric oxygen (HBO2) treatment on hemorheological parameters of diabetic rats was investigated. This study is a placebo‐controlled, in vivo animal study. 30 streptozocin‐induced diabetic rats were divided into two groups; one group received hyperbaric oxygen treatment while the other did not. Hematological and hemorheological parameters were tested with blood samples collected directly from the heart using surgical procedures. Student t‐tests with a type I (α) error at 0.05 was used to test any significant difference between means of the hematologic and hemorheological parameters of the control (CON) and the HBO2 groups. Compared with the placebo group, hyperbaric oxygen resulted in significant higher lipid peroxidation stress of the erythrocytes and resistance of erythrocytes to deformation in rats of the HBO2 group. Whole blood viscosities measured at shear rates of 5, 150 and 400 s−1 were all higher for the rats in the HBO2 group than those for rats in the control group. In addition, the oxygen delivery index was found to be significantly lower in rats of the HBO2 group. Thus, our work demonstrates that hyperbaric oxygen treatment significantly changes the hemorheological parameters in diabetic rats.
The effects of margination and red cell augmented platelet diffusivity on platelet adhesion in complex flow
Authors: Jordan A. , David T. , Homer‐Vanniasinkam S. , Graham A. , Walker P.
Published: November 2024

The effects of platelet margination and enhanced platelet diffusivity, as induced by red blood cells, on the adhesion of platelets, were investigated for a range of haematocrits, under 2D axi‐symmetric flow, simulating previous in vitro experiments [Microvasc. Res. 17 (1979), 238–262]. The effect of margination was incorporated via use of an elevated platelet inlet mass fraction, Φe, in a manner similar to that of Wootton [Ann. Biomed. Eng. 29 (2001), 321–329], and a shear and haematocrit dependent platelet diffusivity, according to the model presented by Zydney and Colton [Physico Chem. Hydrodyn. 10 (1988), 77–96] was used. A combination of the two models was required to simulate the deposition of platelets to a collagen coated surface, under the complex flow, which exhibited a recirculation zone and stagnation point. Results obtained showed qualitative agreement with in vitro results, for a range of haematocrits (11–50%), and also showed that the effects of margination were not linearly dependent on haematocrit. Agreement may be improved in future simulations by incorporating the effects of depleted cell concentrations in the vortex which have been observed previously [Phil. Trans. Roy. Soc. (Lond.) B279 (1977), 413–445]. It would also be advantageous to devise a full mathematical description for platelet margination effects as a function of shear rate and haematocrit and a description of the accompanying effect of apparent blood viscosity.
Erythrocyte stiffness probed using atomic force microscope
Authors: Lekka Malgorzata , Fornal Maria , Pyka-Fościak Grażyna , Lebed Kateryna , Wizner Barbara , Grodzicki Tomasz , Styczeń Jan
Published: November 2024

The stiffness of erythrocytes in patients (N=45) suffering from certain disorders, such as coronary disease, hypertension, and diabetes mellitus has been assessed using the Atomic Force Microscopy (AFM) and compared with that in a group of healthy individuals (N=13). For each blood sample, around 20 erythrocytes were selected at random and the stiffness of each one was probed in 20–30 arbitrarily chosen points. From these results, distributions of the cell Young's modulus (YM) were determined. Average values and widths of YM distributions significantly increased in samples taken from diabetes mellitus patients and cigarette smokers, as compared to those taken from healthy donors. At the same time, the average values of YM were found to increase as a function of the patient's age. We demonstrated that the atomic force microscope is a very sensitive tool for determination of cell stiffness with every prospect of a routine application as a diagnostic tool in quantitative analysis of the physiological and pathological states of red blood cells.
Modulation of proteoglycan production by cyclic tensile stretch in intervertebral disc cells through a post-translational mechanism
Authors: Benallaoua Mourad , Richette Pascal , François Mathias , Tsagris Lydia , Revel Michel , Corvol Maité , Poiraudeau Serge , Savouret Jean-François , Rannou François
Published: November 2024

Proteoglycan production is one of the major extracellular matrix components implicated in the dynamic process of intervertebral disc degeneration. Mechanical stress is an important modulator of the degeneration, but the underlying molecular mechanism at the proteoglycan level remains unclear. The aim of this work was to study the regulation of proteoglycan production by cyclic tensile stretch applied to intervertebral disc annulus fibrosus cells. Matrix metalloproteinases do not seem to be implicated in the regulation of proteoglycan production. By contrast, nitrite oxide production is induced by cyclic tensile stretch, in a time, intensity, and frequency dependant manner. Using a non-specific nitric oxide synthases inhibitor [NG-methyl-L-arginine (L-NMA)], we suppress totally the inhibition of proteoglycan production induced by cyclic tensile stretch suggesting the implication of nitric oxide synthases in the observed phenomenon. Introducing the transcriptional inhibitor 5,6-dichloro-1-β-D-ribofuranosylbenzimidazole or a more specific inhibitor of nitric oxide synthases II [N-iminoethyl-L-lysine (L-NIL)] did not affect the decreased proteoglycan production, which suggests a post-translational regulation. In contrast, N-omega nitro-L-arginine (L-NNA) a more specific inhibitor of NOS I and III abrogated the cyclic tensile stretch-dependant inhibition of proteoglycan production. These results suggest that cyclic tensile stretch regulates proteoglycan production through a post-translational mechanism involving nitrite oxide. This result could be of interest in the development of local therapeutic strategies aimed at controlling intervertebral disc degeneration.
Dynamic compressive strain influences chondrogenic gene expression in human mesenchymal stem cells
Authors: Campbell Jonathan J. , Lee David A. , Bader Dan L.
Published: November 2024

This study tests the hypothesis that dynamic compressive strain selectively enhances chondrogenic differentiation by human mesenchymal stem cells (MSCs). Primary MSCs were isolated and expended in monolayer culture. The cells were seeded in alginate constructs or in pellet culture. The time course of chondrogenic differentiation was assessed by real-time QPCR of mRNA expression analysis for cartilage specific markers. Collagen types II and X mRNA, not present in undifferentiated MSCs, were detectable by 2–4 days of chondrogenic induction and continued to rise significantly throughout the culture period of 10 days (p<0.001). Basal levels of gene expression for Sox-9 and aggrecan were evident in undifferentiated MSCs, although chondrogenic induction for a period of 8 days resulted in an increased trend in the gene expression levels. The alginate system was also used in mechanical conditioning studies. Dynamic compression was applied, in an intermittent regimen, at a strain amplitude of 15% and frequency of 1 Hz in the presence and absence of 10 ng/ml TGFβ3, for a period of 8 days. Results indicated significant changes in the levels of mRNA expression for the chondrogenic markers. For example, by day 8, the application of the strain regimen alone caused an up-regulation in all the chondrogenic markers compared to the control samples (no TGFβ, no compression). However, the combined effects of strain and TGFβ on these markers were more complex than purely additive.
Flow behaviour of a POSS biopolymer solution
Authors: Kidane Asmeret G. , Edirisinghe Mohan J. , Bonhoeffer Philipp , Seifalian Alexander M.
Published: November 2024

A non-biodegradable polyhedral oligomeric silsesquioxane (POSS) nanocomposite biopolymer has been developed for fabrication of medical devices and for tissue engineering human organs. The polymer in solution, containing 2 wt% of POSS, has been synthesized, characterized and investigated to determine its key rheological properties. Thus, the variation of shear stress and viscosity as a function of shear rate has been determined at ambient temperature to estimate yield stress and the index of pseudoplasticity, respectively. The temperature dependence of viscosity and the effect of ageing on the viscosity of the polymer have also been investigated. Results are compared with those of a conventional polycarbonate urethane (PCU) polymer solution. The POSS-PCU polymer solution shows near-Newtonian behaviour in the shear rate range to 1000 s−1, having an apparent viscosity of ∼3000 mPa s and a pseudoplasticity index of 0.90, decreasing slightly as the polymer solution is aged over 9 months. The temperature dependence of viscosity of the POSS polymer is extremely low and does not change with ageing but the yield strength increases from 2.7 Pa to 8.3 Pa.
A General Equilibrium of COVID-19 and Environmental Economy
Authors: Choi Jai-Young , Yu Eden
Published: November 2024

This article investigates the economic implications of coronavirus disease 2019 (COVID-19) pandemic in the 2×3 Heckscher-Ohlin model of general equilibrium by integrating the interactive relationships among COVID-19 pandemic, environment and the economy. We consider the environment (a) as a by-product of COVID-19 pandemic, (b) as a public input used for production of goods and services and (c) as a public good directly affecting social utility. A crucial feature of the model is the short-run versus the log-run environmental effects of COVID-19. It is shown that the signs of the environmental response to COVID-19, relative magnitudes of the sectoral environment-output responses and the sectoral factor intensities jointly determine the effects of COVID-19 on factor prices, sectoral outputs and employment and stability of the environmental economy.

We show while COVID-19 is bad for society in the short-run; however, in the long-run COVID-19 may be welfare-improving under certain conditions regarding the response of the environment to the human remedial measures. Furthermore, for an environmental economy to be dynamically stable, the net environmental effect of COVID-19 should move in the positive direction; specifically, if the environment is at equilibrium (disequilibrium), the optimum optimorum is free trade policy together with lump-sum income tax used to subsidise the production of counteractive pandemic measures.

JEL Codes: F51, F11, I18, Q50
Terahertz Imaging Detects Oral Cariogenic Microbial Domains Characteristics
Authors: Zhang A. , Lei L. , Cheng L. , Yin H. , Zhang C. , Luo J. , Wu F. , Hu M. , Cheng R. , Hu T.
Published: November 2024

Dental caries, associated with plaque biofilm, is highly prevalent and significantly burdens public health. Streptococcus mutans is the main cariogenic bacteria that adheres to the tooth surface and forms an abundant extracellular polysaccharide matrix (EPS) as a cariogenic biofilm scaffold. S. mutans RNase III–encoding gene ( rnc) and a putative chromosome segregation protein-encoding gene ( smc) are potentially associated with EPS production. In addition, complex interactions between S. mutans and other oral microorganisms synergistically or antagonistically affect the cariogenicity. Commensal streptococci suppress the growth of cariogenic pathogens, whereas Candida albicans mediates the formation of cariogenic biofilm through aggregation and dual-species biofilm formation with S. mutans. However, label-free detection of cariogenic microbial interactions with the EPS matrix is still challenging during laboratory investigations. Herein, we hypothesized that the S. mutans rnc-smc operon affects EPS production and aimed to observe streptococci, S. mutans, and S. mutans–C. albicans using terahertz scanning near-field optical microscopy (THz s-SNOM). The light in the 0.1- to 0.3-THz frequency range interacted with the sample through a nano-probe tip by a point-by-point scanning process. Additional noise reduction of the original image was achieved by a dual kernel Gaussian filter. The monospecies of streptococci, S. mutans smc/rnc mutants, and the dual-species of S. mutans–C. albicans were scanned by THz s-SNOM. This technique provided terahertz near-field scanning images of S. mutans smc/rnc mutants, streptococci, and dual-species of S. mutans–C. albicans. Additional analysis of the original images potentially revealed the structures of the strains, such as cell diameters and cell wall thickness. In conclusion, the results suggested that the S. mutans rnc-smc operon regulates EPS production. Furthermore, this novel label-free detection of a THz near-field scanning technique had the potential to observe the morphologies of bacterial cells and EPS matrix.
Vietnamese diaspora in Thailand and the making of transnationality
Authors: Nguyen Tu Anh Thi
Published: November 2024

Diaspora and transnationalism have been known to be intertwiningly related. Compared to the transnational connectivity of the Vietnamese diaspora residing in the West, the ones conducted by those living in Thailand have not yet received sufficient attention. The study seeks to investigate the trans-border connections of Vietnamese-Thais from when they held refugee status to the present day when Thai citizenship was granted, and to analyze differences in transnational making between the second and third diaspora generations. In-depth interviews, participant observation and document research were utilized. The findings reveal that being labeled as a refugee limited the transnationality of the Vietnamese diaspora and distanced nationalism from their homeland. In contrast, possessing the host country’s citizenship facilitates community engagement in multiple trans-border ties with both their home country and other Vietnamese diaspora groups settling around the world. Unlike the second-generation parents, the third generation did not experience a far-distanced nationalism with their ancestral country. Contemporarily, the third generation enjoys transnationality like their second-generation parents, but in a more “trendy” way.
Personalized nutrition after discharge for pancreatic surgery: A study protocol
Authors: Pizzocaro Erica , Vella Roberta , Frigerio Isabella , Giardino Alessandro , Regi Paolo , Scopelliti Filippo , Bannone Elisa , Girelli Roberto , Bignotto Laura , Dal Mas Francesca , Cobianchi Lorenzo , Di Renzo Laura , Butturini Giovanni
Published: November 2024

Background: Pancreatic cancer has an increasing incidence and prevalence trend. Its prognosis is negatively affected by poor/altered nutritional status. Therefore, nutritional interventions play a critical/pivotal role at any stage. Despite being included in the prehabilitation items of Enhanced Recovery After Surgery (ERAS) protocols for pancreatic surgery, nutritional recommendations concerning early post-discharge period are lacking. Aim: To assess the acceptability and feasibility of a personalized and standardized food plan for patients following pancreatic surgery. A secondary aim is to determine if adherence to a personalized food plan is linked to improved postoperative outcomes. Methods: A prospective monocentric cohort study will be performed, including 180 patients undergoing pancreatic surgery. Body composition, nutritional, muscular, and hydro-electrolyte status will be assessed with bio-impedance analysis (BIA). Patients will receive a personalized nutritional plan after discharge for the following 45 days. Summary: Detailed nutritional indications have been formulated with broad consensus for the pre-operative (prehabilitation) and postoperative period. No previous study has specifically formulated or validated a nutritional intervention focused on the early post-discharge period. The results of this study might contribute to paving the way for future research and to broaden nutritional recommendations within the ERAS protocol.
Exploring the association of dietary inflammatory index, disease progression and cellular integrity in chronic kidney disease: A cross-sectional study
Authors: Bhat Prathiksha R , Urooj Asna , Nalloor Srinivas
Published: November 2024

Background

While the anti-inflammatory effects of specific nutrients are well established, there is limited research on the relationship between overall dietary patterns and chronic kidney disease (CKD). Therefore, we aimed to assess the association between dietary inflammatory index (DII) scores and biochemical and body composition parameters in pre-dialysis CKD patients.

Methods

The DII scores of 143 pre-dialysis CKD subjects were calculated using 24-h recalls. Body composition was measured using bioelectric impedance-based InBody 770. Oxidative stress and total antioxidant capacity were measured using thiobarbituric acid reactive substances (TBARS), ferric-reducing antioxidant power (FRAP), and uric acid-independent FRAP (FRAP_UA) assays respectively. C-reactive protein (CRP) was selected as an inflammatory marker while other biochemical parameters were analysed using diagnostic kits.

Results

Subjects were categorized into early-stage CKD (ES; eGFR: 30 to 59 ml/min/1.73 m2) and late-stage CKD (LS; eGFR: < 30 ml/min/1.73 m2). The ES group had a lower extracellular to total body water ratio (p < 0.01) and higher levels of whole-body phase angle (p < 0.01) compared to the LS group. However, FRAP_UA was higher in the LS group (p < 0.05). For each increase in DII score by 1, eGFR decreased by 2.31 ml/min/1.73 m2 (p < 0.01) and phase angle by 0.11 degrees (p < 0.05). Consuming cereals and millets, other vegetables, roots and tubers, spices, poultry, oils and fats significantly contributed to the anti-inflammatory potential of the diet (p < 0.01).

Conclusion

A pro-inflammatory diet was associated with disease progression and decreased cell integrity, underscoring the importance of its consideration in CKD management.
Cerebral microvascular physiology associated with white matter lesion burden differs by level of vascular risk in typically aging older adults
Authors: Gassner Gabriele M , Damestani Nikou L , Wheeler Natalie S , Kufer Jan A , Yadav Shrikanth M , Mellen Sarah F , Maina Katherine N , Salat David H , Juttukonda Meher R
Published: November 2024

White matter lesions (WMLs) are prevalent with aging, and higher WML burden has been observed in older adults with vascular diseases. While the physiology underlying the formation of WMLs is not known, various risk factors are associated with high WML burden. Here, we investigated the relationship between vascular risk factors and microvascular physiology (i.e., oxygen supply and oxygen extraction fraction [OEF]) and their association with WML burden. Forty-one typically aging adults (60–80 years) were classified into high or low vascular risk based on common modifiable vascular risk factors (hypertension, diabetes, hyperlipidemia, and overweight). These groups were subdivided into high or low WML burden. Differences in microvascular physiology (oxygen supply and OEF) were then compared between and within groups. Overall, OEF was significantly higher in the high vascular risk group compared to the low vascular risk group (p < 0.01). In the low vascular risk subgroup, OEF was uniquely lower in the individuals with high WML versus low WML burden (p = 0.02), despite no differences in oxygen supply between these subgroups (p = 0.87). The coupling of impaired OEF with the absence of compensatory physiology, such as elevated oxygen supply, may represent an important mechanism underlying WML burden in individuals with low vascular risk factors.
An expert ensemble for detecting anomalous scenes, interactions, and behaviors in autonomous driving
Authors: Ji Tianchen , Chakraborty Neeloy , Schreiber Andre , Driggs-Campbell Katherine
Published: November 2024

As automated vehicles enter public roads, safety in a near-infinite number of driving scenarios becomes one of the major concerns for the widespread adoption of fully autonomous driving. The ability to detect anomalous situations outside of the operational design domain is a key component in self-driving cars, enabling us to mitigate the impact of abnormal ego behaviors and to realize trustworthy driving systems. On-road anomaly detection in egocentric videos remains a challenging problem due to the difficulties introduced by complex and interactive scenarios. We conduct a holistic analysis of common on-road anomaly patterns, from which we propose three unsupervised anomaly detection experts: a scene expert that focuses on frame-level appearances to detect abnormal scenes and unexpected scene motions; an interaction expert that models normal relative motions between two road participants and raises alarms whenever anomalous interactions emerge; and a behavior expert which monitors abnormal behaviors of individual objects by future trajectory prediction. To combine the strengths of all the modules, we propose an expert ensemble (Xen) using a Kalman filter, in which the final anomaly score is absorbed as one of the states and the observations are generated by the experts. Our experiments employ a novel evaluation protocol for realistic model performance, demonstrate superior anomaly detection performance than previous methods, and show that our framework has potential in classifying anomaly types using unsupervised learning on a large-scale on-road anomaly dataset.
Co-creating open initiatives at De La Salle University Libraries: The Animo Repository experience
Authors: Cruz Luis Ezra , Viray Mennie Ruth , Flores Roana Marie
Published: November 2024

The launch of the Animo Repository in 2020 marked a significant advancement in De La Salle University Libraries’ open access initiatives. The Animo Repository functions as the central archive for the university's scholarly outputs, including faculty research, electronic theses and dissertations, special collections and university journal publications. Beyond serving as the central repository for De La Salle University’s scholarly outputs, the platform's robust hosting and publishing infrastructure is designed to optimize the discoverability and accessibility of these records. The primary focus of this study is to examine the collaboration between De La Salle University Libraries’ and De La Salle University Publishing House in utilizing the Animo Repository for open access journal publishing. It distinguishes between hosting and publishing roles, explores the integration process, and evaluates the initial outcomes and impacts. The study contributes to the growing literature on open library publishing and institutional repositories, emphasizing more equitable research access and dissemination practices.
The impact of big data on university libraries in Bangladesh
Authors: Rahman Habibur , Ghazali Asmadi Mohammed , Sawal Mohd Zool Hilmie Mohamed
Published: November 2024

This study investigates the impact of big data on university libraries in Bangladesh, focusing on areas such as resource accessibility, decision-making, user experiences, academic research and information management. By conducting interviews with 21 library professionals and employing thematic analysis, the study reveals critical insights. Big data significantly enhances resource accessibility by enabling customized collections and supports user-centric decision-making in library operations. It also improves user experiences through personalized recommendations and seamless navigation. Moreover, big data's analysis of citation patterns and collaborative networks bolsters academic research while addressing information overload and optimizing information retrieval processes. This research provides a thorough examination of big data's practical implications in university libraries, offering valuable insights for professionals, researchers and policymakers. It emphasizes the necessity of a proactive approach to leveraging big data's transformative potential in knowledge management, thereby shaping the future of academic libraries.
Experimental investigation on impact, compressive and losipescu shear strength of glass/flax hybrid composites for automotive application
Authors: Gnanakumar Ganesan , Selvaraj Muthunadar , Murugan Ramasamy
Published: November 2024

In Current scenario, polymer hybrid composites are extensively utilized as substitutes for traditional materials in various engineering applications. The hybridization technique for manufacturing composite materials through the integration of organic and synthetic fibres is experiencing significant growth in industries such as aerospace, automotive, military, and structural applications. These manufactured composites possess notable attributes such as eco-friendliness and sustainability. Due to the high tensile strength and amazing antistatic properties, flax fibre is considered to hybrid with glass fibre and forms a hybrid material with polyester resin. In this investigation, woven flax fibre was treated with alkaline solution and hybridized with woven glass fibre with polyester resin through vacuum bag moulding process. Three types of glass/flax hybrid composites are prepared to analyse the impact strength, compressive strength and shear strength are tested as per the various ASTM standard. Experimental results showed that the developed glass/flax hybrid composites achieved enhanced impact strength, compression strength and shear strength performance compared with flax reinforced epoxy composite.
Narrative Identity, Traits, and Trajectories of Depression and Well-Being: A 9-Year Longitudinal Study
Authors: Lind Majse , Ture Sebnem , McAdams Dan P. , Cowan Henry R.
Published: November 2024

Mental health and well-being tend to improve with age, and personality differences affect these trajectories. Although it is well established that dispositional traits, such as extraversion and neuroticism, relate to well-being, the incremental validity of other important personality constructs, such as narrative identity, remains unknown. Across 9 years, 157 late-midlife adults ( Mage = 56.4 years, SD = 0.96) self-reported their well-being and symptoms of depression each year and wrote an annual narrative account describing their greatest life challenge ( Nchallenges = 1,211). The narrative accounts were content-coded for themes of agency and communion. Results showed that themes of agency and communion in narrative identity were significantly and uniquely associated with well-being and depression across time, over and above the effects of traits. The benefits of considering both narrative identity and dispositional personality traits as they jointly apply to mental health are discussed.
Diagnostic testing in psychiatry: insights and examples from a Bayesian perspective
Authors: Maguire Paul A , Looi Jeffrey CL
Published: November 2024

Objective

To demonstrate the application of Bayes’ theorem to diagnostic testing in clinical settings, especially with respect to rare diseases, enhancing an understanding of pre-test probability and its implications.

Conclusion

Bayes’ theorem enables the revision of the conditional probabilities of an event occurring when new information is acquired. It demonstrates that when the prevalence of a disease is very low, there are a high number of false positives, thereby reducing the clinical utility and cost benefit profile of the diagnostic test, even in the presence of relatively high sensitivities and specificities of the chosen test.
Thermodynamically consistent modeling of viscoelastic solids under finite strain
Authors: Kunzemann Mario , Doppelbauer Leonhard K , Preuer Rene , Pechstein Astrid
Published: November 2024

The present article is concerned with modeling the viscoelastic behavior of Polydimethylsiloxane (PDMS) in large-strain regime. Starting from the basic principles of thermodynamics, an incremental variational formulation is derived. Within this model, the free energy density and dissipation function determine elastic and viscous properties of the solid. The main contribution of this paper is the estimation of the parameters in the proposed phenomenological model from measurements conducted on Sylgard184 samples. This non-linear material model simplifies to a Prony-series representation in frequency domain in case of small deformations. The coefficients of this Prony-series are detected from dynamical temperature mechanical analysis measurements. Time-temperature superposition allows to combine measurements at different temperatures, such that a sufficiently large frequency range is available for subsequent fitting of Prony-parameters. A set of material parameters is thus provided. The incremental variational formulation directly lends itself to finite element discretization, where an efficient and stable choice of elements is proposed for radially symmetric problems. This formulation allows to verify the proposed model against experimental data gained in ball-drop experiments.
‘There is Something Missing Out There…’: A Performative Portrait Approach to Understanding the Experience of Living with Dementia
Authors: Phenwan Tharin , Rodriguez-Dorans Edgar
Published: November 2024

People with dementia (PwD) often face symptoms that influence their memories and capabilities to express themselves meaningfully. These symptoms make it particularly challenging for qualitative researchers to capture and demonstrate PwD's complex experiences with the traditional reliance on textual outputs. This paper offers a novel approach through performative portraiture to demonstrate and argue that the use of this approach is needed as an alternative academic output that diverges from textual reliance. The paper begins with an overview of the research, which aimed to improve understanding of the initiation and revision process of advance care planning with and for PwD and was used as a baseline to create ‘Dave’ as a young PwD based on the verbatim interview transcripts of 13 PwD. The methodological process is outlined, and findings are then chronologically discussed. The paper concludes with the strengths and limitations of this approach as well as its future implications.
Consistent linearization of micromorphic continuum theories
Authors: McAvoy Ryan C
Published: November 2024

We outline the procedure of consistent linearization and apply it to the micromorphic, microstretch, and micropolar theories of continua. This yields tractable linear theories for nonlinearly elastic microstructured materials undergoing finite deformations. The results may be readily utilized in computational mechanics, stability and bifurcation analyses, and small-deformation problems in the context of these types of continua. Our results generalize those existing in current literature and facilitate their recovery upon incorporating appropriate kinematic and constitutive assumptions.
Correlates of Food Contamination by Heavy Metals in Northwest Nigeria
Authors: Ibrahim Usman Muhammad , Karkarna Mustapha Zakariyya , Babura Salisu Muazu , Matazu Mujahid Ajah , Jibo Abubakar Mohammed , Umar Muhammad Lawan , Aliyu Muktar Hassan
Published: November 2024

Background:

The increasing cases of chronic kidney disease is a global public health concern. The potential link between consumption of food contaminated with heavy metals and development of end stage renal disease is becoming an emerging challenge. This study aimed to identify heavy metal contaminants in food and environmental risk factors for development of chronic kidney disease in Nigeria.

Methods:

Cross-sectional survey in 4 high burden local government areas of Jigawa state, northwest Nigeria.

Results:

The median age of the respondents was 45 years (interquartile range = 30–80) years. All the households had normal values of cadmium in the food analyzed. The majority of households (97.8%) had elevated mercury levels in analyzed food. Approximately 4.2% of households had increased lead levels. Elevated mercury levels were significantly higher in households that did not cultivate the food they consumed (median = 2.503 mg/kg, P = .05), those that did not use fertilizer on their farms (median = 2.522 mg/kg, P = .02), and those whose farms were located outside their communities (median = 2.733 mg/kg, P = .020). Households that did not use fertilizer on the farm (median = 0.027 mg/kg, P = .007), and those that primarily consumed rice (median = 0.023 mg/kg, P = .005) had significantly higher lead concentrations.

Conclusions:

We identified high levels of mercury in food samples of the majority of the households studied. Elevated levels of mercury were associated with food cultivation practices and fertilizer use. We recommend future studies that will identify points of food contamination and inform the development of appropriate environmental remediation measures.