bluuebunny/crossref_metadata_2025 huggingface dataset:
A mechanistic computational framework to investigate the hemodynamic fingerprint of the blood oxygenation level‐dependent signal
Authors: Báez‐Yáñez Mario Gilberto , Siero Jeroen C. W. , Petridou Natalia
Published: August 2023

Blood oxygenation level‐dependent (BOLD) functional magnetic resonance imaging (fMRI) is one of the most used imaging techniques to map brain activity or to obtain clinical information about human cortical vasculature, in both healthy and disease conditions. Nevertheless, BOLD fMRI is an indirect measurement of brain functioning triggered by neurovascular coupling. The origin of the BOLD signal is quite complex, and the signal formation thus depends, among other factors, on the topology of the cortical vasculature and the associated hemodynamic changes. To understand the hemodynamic evolution of the BOLD signal response in humans, it is beneficial to have a computational framework available that virtually resembles the human cortical vasculature, and simulates hemodynamic changes and corresponding MRI signal changes via interactions of intrinsic biophysical and magnetic properties of the tissues. To this end, we have developed a mechanistic computational framework that simulates the hemodynamic fingerprint of the BOLD signal based on a statistically defined, three‐dimensional, vascular model that approaches the human cortical vascular architecture. The microvasculature is approximated through a Voronoi tessellation method and the macrovasculature is adapted from two‐photon microscopy mice data. Using this computational framework, we simulated hemodynamic changes—cerebral blood flow, cerebral blood volume, and blood oxygen saturation—induced by virtual arterial dilation. Then we computed local magnetic field disturbances generated by the vascular topology and the corresponding blood oxygen saturation changes. This mechanistic computational framework also considers the intrinsic biophysical and magnetic properties of nearby tissue, such as water diffusion and relaxation properties, resulting in a dynamic BOLD signal response. The proposed mechanistic computational framework provides an integrated biophysical model that can offer better insights regarding the spatial and temporal properties of the BOLD signal changes.
Design, synthesis, and properties of soluble intrinsic black polyimide bearing tetraphenylcyclopentadienone units
Authors: Tan Jinghua , Shen Junyi , Huang Jie , Yuan Jiazhen , Liu Xueyuan , Li Huipeng , Xie Fengyun , Zhao Chunbo , Liu Yiwu
Published: August 2023

Black polyimides (BPIs) have gained increasing attention because of their growing demands in optoelectronic areas. However, the commonly used BPI containing carbon black suffers from the decreases of mechanical and electrical performances. In this work, a soluble intrinsic BPI (TPCPDFPPI) was prepared by the reaction of 4,4′‐(hexafluoroisopropylidene) diphthalic anhydride (6FDA) and a new diamine (TPCPDFPDA) bearing tetraphenylcyclopentadienone (TPCP) connected with benzene and fluorene units. TPCP grafted with benzene and fluorene units acted as a chromophore that shifted the absorption range of PI toward the long‐wave direction. The resulting TPCPDFPPI possessed whole visible‐light absorption characteristic and therefore exhibited high blackness and opacity. Additionally, TPCPDFPPI displayed superior solubility, mechanical and electrical performance. Theoretical calculations exhibited that the visible‐light absorption responsible for the blackness of TPCPDFPPI was chiefly ascribed to the HOMO to LUMO electron transition in the diamines, where the electrons were primarily migrated from the 2,5‐position aryl groups to the cyclopentadienone. This work offers a promising strategy for improving the overall properties of BPIs for photo‐electronic areas.
Advances of phytotherapy in ischemic stroke targeting PI3K/Akt signaling
Authors: Liu Tianlong , Wang Wenjun , Li Xiaolin , Chen Yidan , Mu Fei , Wen Aidong , Liu Minna , Ding Yi
Published: August 2023

The pathogenesis of ischemic stroke is complex, and PI3K/Akt signaling is considered to play a crucial role in it. The PI3K/Akt pathway regulates inflammation, oxidative stress, apoptosis, autophagy, and vascular endothelial homeostasis after cerebral ischemia; therefore, drug research targeting the PI3K/Akt pathway has become the focus of scientists. In this review, we analyzed the research reports of antiischemic stroke drugs targeting the PI3K/Akt pathway in the past two decades. Because of the rich sources of natural products, increasing studies have explored the value of natural compounds, including Flavonoids, Quinones, Alkaloids, Phenylpropanoids, Phenols, Saponins, and Terpenoids, in alleviating neurological impairment and achieved satisfactory results. Herbal extracts and medicinal formulas have been applied in the treatment of ischemic stroke for thousands of years in East Asian countries. These precious clinical experiences provide a new avenue for research of antiischemic stroke drugs. Finally, we summarize and discuss the characteristics and shortcomings of the current research and put forward prospects for further in‐depth exploration.
The aesthetics of sustainable industrial design: Form and function in the circular design process
Authors: Sareh Pooya
Published: August 2023

The relationship between form and function has long been a point of debate in the design community. Particularly, the famous principle ‘form follows function’ has been a focal point of such discussions. Since its introduction, many studies have been undertaken by theorists and practitioners to challenge or disprove this injunction. Furthermore, from the modern perspective of sustainability which has attracted global attention over the past few decades, there is a crucial link between design and sustainability. That is, poor designs, generally, lead to poor products which contribute to environmental and economic degradation. Consequently, understanding the relationship between form and function in design could contribute to a more sustainable environment. In this paper, first, we explore the views of some influential figures of the twentieth century's industrial design on this essentially philosophical, yet practically crucial, axiom of modernism. Then, we propose a design process model for aesthetic‐sustainable industrial design drawing on a theory of design aesthetics and the principles of circular design. This model integrates a circular design module into the industrial designer's theory of aesthetics to complement the design process in terms of sustainability. The proposed design process model could help designers establish an appropriate relationship between the form and the intended function of a product to contribute to lowering its environmental impact.
Evaluation of soil arsenic pollution and phytoaccumulation capabilities of 24 indigenous plant species in Barak Valley, South Assam, India
Authors: Barhai Akan , Das Suchismita
Published: August 2023

This study investigated the concentrations of arsenic (As) in soil and plant biomass from the Barak Valley in South Assam, India. Soil samples showed concentrations ranging from 6.06 ± 0.84 mg/kg to 18.61 ± 1.52 mg/kg, with an average of 10.60 ± 3.15 mg/kg, 41.67% of the sample exceeding uncontaminated ranges (0.1–10 mg/kg). Ecological risk assessments such as contamination factors, pollutant load index, geo‐accumulation index, and anthropogenicity identified varying contamination levels across sampling points. A total of 24 plant species were collected, ferns (two species), shrubs (five species), grass (six species), and herb (11 species). The concentration of As in different plants types decreased in the order of fern (393.45 ± 159.63 mg/kg) > shrub (20.48 ± 7.25 mg/kg) > herb (17.92 ± 13.75 mg/kg) > grass (14.98 ± 13.80 mg/kg). Plant species, namely Pityrogramma calomelanos, Christella dentata, Mimosa pudica, Chromolaena odorata, Leucas aspera, Persicaria decipiens, Melastoma malabathricum, and Clerodendrum infortunatum, accumulated higher concentrations of As in their above‐ground parts compared to roots and were categorized as tolerant accumulators (TF > 1). By incorporating these plant species into phytoextraction strategies, the region can benefit from their unique properties and abilities to effectively remediate arsenic‐contaminated sites, ultimately improving the affected areas' environmental and human health conditions.
Oestrus ovis sinusitis in a dog
Authors: Azoulay Florian , Girard Nicolas , Gatel Laure , Besson Julie , Fritz Julien
Published: August 2023

A 2‐year‐old, female Cane Corso was presented for chronic epistaxis, reverse sneezing and purulent nasal discharge. Clinical examination was unremarkable. Bloodwork revealed a mild anaemia. Computed tomography of the nasal cavity was consistent with right frontal sinusitis with suspected foreign bodies. Surgical approach of the right sinus by frontal osteotomy allowed to perform an endoscopically guided extraction of a 15‐mm white ringed worm and multiple black worm‐like structures. The evaluation by an EVPC diplomate confirmed an Oestrus ovis infestation. After endoscopic lavage of the frontal sinus, the dog went home with an ivermectin‐based treatment. It was presented 7 months later for a recurrence of the clinical signs. Tomography and surgical approach to the right frontal sinus revealed persistent presence of the O. ovis infestation. After surgical removal of the parasite and oral isoxazoline treatment, the dog had no signs of clinical recurrence. Follow‐up computed tomography scan confirmed complete resolution of the sinusitis.
An analytical frequency‐domain model of aerodynamic mass and damping of floating wind turbines
Authors: Yang Can , Xiao Longfei , Chen Peng , Cheng Zhengshun , Liu Mingyue , Liu Lei
Published: August 2023

The fore‐aft motion of the rotor‐nacelle assembly (RNA) of a rotating floating wind turbine (FWT) can cause an oscillation in aerodynamic thrust, which may be equivalently treated as frequency‐dependent aerodynamic mass and damping effects. In this study, an explicit frequency‐domain analytical model is proposed to calculate the equivalent aerodynamic mass and damping of FWTs, with proper linearization of control system. Assuming that an FWT operates under steady wind conditions and a forced oscillation is exerted at the RNA along the wind direction, the thrust fluctuations are equivalently represented by the force and moment acting on the nacelle instead of pure aerodynamic loads. Based on the thrust oscillation expression, equivalent aerodynamic mass and damping are derived analytically. After verifying the model by numerical comparison, it is used to demonstrate equivalent aerodynamic mass and damping of three wind turbines (5–15 MW). Effects of wind turbine up‐scaling and controller dynamics are addressed. Results show that equivalent aerodynamic mass and damping present a nonlinear characteristic with oscillation frequency in the below‐rated region, while the relationship is close to linear for higher wind speeds. The effect of wind turbine up‐scaling has a visible impact on equivalent aerodynamic mass and damping, especially at near‐rated wind speed. Controller gains affect equivalent aerodynamic mass and damping and should be tuned reasonably in the controller design for FWTs. Outcomes of our study can be used to establish a frequency‐domain coupled model of FWTs and are beneficial for conceptual design and parameter optimization of the platform of FWTs.
What Makes Problem-Solving Practice Effective? Comparing Paper and AI Tutoring
Authors: Borchers Conrad , Carvalho Paulo F. , Xia Meng , Liu Pinyang , Koedinger Kenneth R. , Aleven Vincent
Published: August 2023

In numerous studies, intelligent tutoring systems (ITSs) have proven effective in helping students learn mathematics. Prior work posits that their effectiveness derives from efficiently providing eventually-correct practice opportunities. Yet, there is little empirical evidence on how learning processes with ITSs compare to other forms of instruction. The current study compares problem-solving with an ITS versus solving the same problems on paper. We analyze the learning process and pre-post gain data from N = 97 middle school students practicing linear graphs in three curricular units. We find that (i) working with the ITS, students had more than twice the number of eventually-correct practice opportunities than when working on paper and (ii) omission errors on paper were associated with lower learning gains. Yet, contrary to our hypothesis, tutor practice did not yield greater learning gains, with tutor and paper comparing differently across curricular units. These findings align with tutoring allowing students to grapple with challenging steps through tutor assistance but not with eventually-correct opportunities driving learning gains. Gaming-the-system, lack of transfer to an unfamiliar test format, potentially ineffective tutor design, and learning affordances of paper can help explain this gap. This study provides first-of-its-kind quantitative evidence that ITSs yield more learning opportunities than equivalent paper-and-pencil practice and reveals that the relation between opportunities and learning gains emerges only when the instruction is effective.
Women’s right to property and the child quantity-quality trade-off: evidence from India
Authors: Tandel Vaidehi , Dutta Arnab , Gandhi Sahil , Narayanan Ashwini
Published: August 2023

We study the effects of a series of state and federal reforms that granted Indian women equal inheritance rights on the quantity and quality of children. Using a difference-in-differences methodology, we find that women who were affected by the state reforms had 0.4 more children. State reforms did not have any effect on children’s heights. To assess the impact of the federal reform, we use panel data on women and a novel treatment based on the timing of their fathers’ deaths. We find that women affected by the reform had on average 0.22 fewer children and had taller children on average. While the federal reform had no effect on the number of daughters born to this group, the number of sons born declined. Thus, we see evidence that granting property rights to women could potentially impact fertility decisions, children’s health outcomes, and gender imbalance.
Influence of the deposition pattern on the interlayer fracture toughness of FDM components
Authors: Lambiase Francesco , Stamopoulos Antonios G. , Pace Francesco , Paoletti Alfonso
Published: August 2023

The present work is aimed at studying the influence of the deposition strategy on the fracture toughness behavior of the inter-layer zone of fused deposition modeling (FDM) 3D-printed parts. Double cantilever beam (DCB) specimens were produced and tested following recognized testing protocols to capture the fracture toughness behavior. The tested conditions involved linear patterns with monodirectional and alternate infill strategies. The difference in the mechanical behavior of the samples was crossed with optical microscopy observations that also enabled the precise quantification of the effective bonding area between consecutive layers. The results indicated that the deposition pattern dramatically influenced the fracture toughness behavior of these components. Monodirectional deposition strategies involved a fracture toughness within 0.75 and 2.4 kJ/m2 for 0° and 90° raster angles, respectively. On the other hand, the fracture toughness of samples manufactured with alternate deposition strategies more than doubled the values mentioned above, being 2 kJ/m2 and 3.9 kJ/m2 for 0/90° and ±45° deposition strategies, respectively, significantly affecting the failure mode as well. These differences become even more evident if the effective bonding area between consecutive layers is considered.
Homogenization and Phase Separation with Space Dependent Wells: The Subcritical Case
Authors: Cristoferi Riccardo , Fonseca Irene , Ganedi Likhit
Published: August 2023

A variational model for the interaction between homogenization and phase separation is considered. The focus is on the regime where the latter happens at a smaller scale than the former, and when the wells of the double well potential are allowed to move and to have discontinuities. The zeroth and first order$$\Gamma $$Γ-limits are identified. The topology considered for the latter is that of two-scale, since it encodes more information on the asymptotic local microstructure. In particular, when the wells are non-constant, the first order$$\Gamma $$Γ-limit describes the contribution of microscopic phase separation, even in situations where there is no macroscopic phase separation. As a corollary, the minimum of the mass constrained minimization problem is characterized, and it is shown to depend on whether or not the wells are discontinuous. In the process of proving these results, the theory of inhomogeneous Modica Mortola functionals is strengthened.
Ulam stability of lamplighters and Thompson groups
Authors: Fournier-Facio Francesco , Rangarajan Bharatram
Published: August 2023

We show that a large family of groups is uniformly stable relative to unitary groups equipped with submultiplicative norms, such as the operator, Frobenius, and Schattenp-norms. These include lamplighters$$\Gamma \wr \Lambda $$Γ≀Λwhere$$\Lambda $$Λis infinite and amenable, as well as several groups of dynamical origin such as the classical Thompson groups$$F, F', T$$F,F′,TandV. We prove this by means of vanishing results in asymptotic cohomology, a theory introduced by the second author, Glebsky, Lubotzky and Monod, which is suitable for studying uniform stability. Along the way, we prove some foundational results in asymptotic cohomology, and use them to prove some hereditary features of Ulam stability. We further discuss metric approximation properties of such groups, taking values in unitary or symmetric groups.
Can acetate via FFA receptors contribute to the diabetogenic effect of statins?
Authors: Levy Finn Olav , Osnes Jan-Bjørn
Published: August 2023

Despite the proven effects of statins in preventing cardiovascular disease, their diabetogenic effect has caused concern. The mechanism of this diabetogenic effect is unknown. We suggest a novel mechanism that may contribute to the diabetogenic effect of statins, through an effect of statins that has apparently escaped previous consideration. Briefly, by inhibiting HMG-CoA reductase, statins may cause accumulation of acetate, which through FFA2 and FFA3 stimulation may inhibit insulin secretion.
Development of plasmid calibrators for absolute quantification of the β-parvalbumin gene in Lophius piscatorius
Authors: Mukherjee Subham , Hanak Petr , Zdenkova Kamila , Musilova Zuzana , Horka Petra , Jilkova Diliara , Cermakova Eliska
Published: August 2023

The real-time quantitative PCR (qPCR) calibration curves are highly reproducible and allow the generation of specific, sensitive, and reproducible data that can be used for gene quantification. However, it is important to rigorously validate the external calibration curve model in qPCR since absolute quantification is dependent on the standards used. We present a method for standardising qPCR-based quantification of the β-parvalbumin (β-pvalb) gene of Lophius piscatorius, a major fish allergen, using a plasmid DNA (pDNA) calibrator. In parallel experiments, standard curves were generated and compared from the genomic DNA (gDNA) isolated from L. piscatorius and pDNA carrying the target, pvalb. The commutability of pDNA and gDNA calibrators for the quantification of β-pvalb was assessed by employing a TaqMan qPCR, targeting the second intron of the pvalb gene of L. piscatorius. Higher PCR efficiencies, good linearity, and lower standard deviation (S.D.) values were observed with pDNA instead of gDNA calibrants. pDNA calibrants exhibited a lower bias in terms of closeness to the expected value of unknown samples than their genomic counterparts. The assay was specific and sensitive, where the limit of detection (LOD) and limit of quantification (LOQ) were five copies and ten copies per reaction. The short-term stability study of the pDNA calibrants indicated its stability for 60 days at − 20 °C and 30 days at 4 °C. The efficient results indicated a plasmid calibrator as a potential tool for absolute quantification of the pvalb gene and an alternative to conventional gDNA standards.
Pre-pectoral Breast Reconstruction: Surgical and Patient-Reported Outcomes of Two-Stages vs Single-Stage Implant-Based Breast Reconstruction
Authors: Zingaretti Nicola , Piana Michele , Battellino Laura , Galvano Francesca , De Francesco Francesco , Riccio Michele , Beorchia Yvonne , Castriotta Luigi , Parodi Pier Camillo
Published: August 2023

Background

Two-stages pre-pectoral breast reconstruction may confer advantages over direct to implant (DTI) and subpectoral reconstruction in selected patients who have no indication for autologous reconstruction. The primary endpoint of the study was to evaluate and compare the incidence of capsular contracture in the pre-pectoral two-stages technique versus the direct to implant technique. Complications related to the two surgical techniques and patient satisfaction were also evaluated.

Methods

A retrospective review of 45 two stages and 45 Direct-to-implant, DTI patients was completed. Acellular dermal matrix was used in all patients. An evaluation of anthropometric and clinical parameters, surgical procedures and complications was conducted. Minimum follow-up was 12 months after placement of the definitive implant.

Results

There was no statistically significant difference in the rate of capsular contracture in the two groups. Rippling occurred more in DTI reconstruction. In the two-stages reconstruction, lipofilling was applied more often and there was a higher incidence of seroma. Patient satisfaction extrapolated from the Breast Q questionnaire was better for patients submitted to two-stage implant-based breast reconstruction.

Conclusion

Dual-stage pre-pectoral reconstruction with acellular dermal matrix appears to be a good reconstructive solution in patients with relative contraindications for one-stage heterologous reconstruction with definitive prosthesis and no desire for autologous reconstruction.
Comparative In Vivo Study of Solid-Type Pure Hyaluronic Acid in Thread Form: Safety and Efficacy Compared to Hyaluronic Acid Filler and Polydioxanone Threads
Authors: Kim Jong-Ho , Han Man Wong , Lee Myoung-Han , Kweon Dong-Keon , Park Young Jin , Heo Chan Yeong
Published: August 2023

Introduction

Although various products are commonly used for skin rejuvenation, solid-type hyaluronic acid (HA) as an injectable form has not been researched or utilized. This study aimed to demonstrate the safety and efficacy of solid-type HA in thread form, which differs from the conventional gel-type HA commonly used.

Method

Solid-type HA threads, conventional HA fillers, and polydioxanone (PDO) threads were inserted into the dorsal subcutaneous layer of mice. Photographs were taken on days 0, 1, 3, and 7, and on day 7, the samples were harvested for histological analysis. Inflammatory reactions and detection of collagen were confirmed through tissue staining, and real-time PCR was conducted to quantify collagen synthesis.

Results

In the histological analysis, the PDO threads exhibited a greater inflammatory response compared to the HA threads. Masson’s trichrome staining revealed a higher degree of collagen synthesis in the HA thread group compared to the HA filler group. While collagen type 1 expression was significantly higher in the PDO thread group than in the HA thread group, the HA thread group showed higher expression levels of collagen type 3. Furthermore, the PDO thread group demonstrated a statistically significant increase in TGF-β1 compared to the HA group.

Conclusion

This in vivo study demonstrated the stable application of solid-type pure HA threads and their potential for inducing collagen production, while also yielding a low inflammatory response. The findings highlight the promising applications of solid-type HA in the field of cosmetic dermatology.

No Level Assigned

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.
Analyzing the role of soil and vegetation spatial variability in modelling hydrological processes for irrigation optimization at large scale
Authors: Hassan Shawkat B. M. , Dragonetti Giovanna , Comegna Alessandro , Lamaddalena Nicola , Coppola Antonio
Published: August 2023

The main purpose of this paper was to study the effect of spatial variability of soil hydraulic properties (HP) and vegetation parameters (VP) (e.g., leaf-area index, LAI, and crop coefficient, Kc) on modelling agro-hydrological processes and optimising irrigation volumes at large scale. Based on this analysis, the effect of partly overlooking the spatial variability of soil HP and/or VP inputs was verified on a 140 ha irrigation sector in “Sinistra Ofanto” irrigation system in Apulia Region, Southern Italy. Five soil profiles were excavated and the HP were measured in all the soil horizons. Additionally, measurements of soil HP were taken in the surface soil layer in ninety sites distributed over the whole irrigation sector. All the HP measurements were carried out using tension infiltrometer. Remote sensing applications were used to obtain LAI and Kc using European Space Agency’s (ESA) Sentinel-2 images with 10 m resolutions. First, distributed (on ninety polygons with an average area of about 1.5 ha) optimal irrigation volumes and related deep percolation volumes at a depth of 80 cm, were computed using an agro-hydrological model and accounting for the actual observed variability of soil HP and VP inputs. The sector scale irrigation and deep percolation volumes were obtained by aggregating the distributed irrigation volumes. This was considered as the reference scenario (hereafter DVS—Detailed Variability Scenario). Then, reduced variability scenarios (hereafter RVS—Reduced Variability Scenario) were considered, where the information on the actual spatial variability of the soil HP and VP was gradually overlooked to find the minimum data set needed to still have sector scale irrigation volumes and related deep percolation volumes comparable to those obtained under the DVS. Results showed that overlooking VP (RVS-VP) variability did not significantly change the optimal irrigation volumes and the deep percolation fluxes. By contrast, neglecting the HP variability (RVS-HP) showed significant effects on both the irrigation and percolation volumes compared to the DVS. The main practical finding was that, at least for the area investigated in this study, hydraulic characterization of one soil profile in an area of approximately 30 ha provides sector scale irrigation volumes and percolation fluxes comparable to those obtained under the DVS, thus by accounting for all the observed local variability.
Three out of four working-age patients have fulfilled expectations towards paid employment six months after total hip or knee arthroplasty: a multicentre cohort study
Authors: Kamp Tamara , Stevens Martin , Vlieland Thea P. M. Vliet , Nelissen Rob G. H. H. , Brouwer Sandra , Gademan Maaike G. J. ,   on behalf of the Longitudinal Leiden Orthopaedics Outcomes of Osteoarthritis Study (LOAS) Group
Published: August 2023

To investigate factors associated with fulfilment of expectations towards paid employment after total hip/knee arthroplasty (THA/TKA). Cohort study including preoperatively employed patients aged 18–64 scheduled for THA/TKA. Expectations were collected preoperatively, and 6 and 12 months postoperatively with the paid employment item of the Hospital-for-Special-Surgery Expectations Surveys (back-to-normal = 1; large improvement = 2; moderate improvement = 3; slight improvement = 4; not applicable = 5). Patients scoring not applicable were excluded. Fulfilment was calculated by subtracting preoperative from postoperative scores (< 0: unfulfilled; ≥ 0: fulfilled). Multivariable logistic regression analyses were conducted separately for THA/TKA at 6 and 12 months postoperatively. Six months postoperatively, 75% of THA patients (n = 237/n = 316) and 72% of TKA patients (n = 211/n = 294) had fulfilled expectations. Older age (TKA:OR 1.08, 95% CI 1.01–1.15) and better postoperative physical functioning (THA:OR 1.10, 95% CI 1.06–1.14; TKA:OR 1.03, 95% CI 1.01–1.06) increased the likelihood of fulfilment. Physical work tasks (THA:OR 0.12, 95% CI 0.03–0.44), preoperative sick leave (TKA:OR 0.33, 95% CI 0.17–0.65), and difficulties at work (THA:OR 0.10, 95% CI 0.03–0.35; TKA:OR 0.41, 95% CI 0.17–0.98) decreased the likelihood of fulfilment. Twelve months postoperatively similar risk factors were found. Three out of four working-age THA/TKA patients had fulfilled expectations towards paid employment at 6 months postoperatively. Preoperative factors associated with fulfilment were older age, mental work tasks, no sick leave, postoperative factors were better physical functioning, and no perceived difficulties at work.
Flow dynamics and heat transfer characterization of confined multiple jets impinging on a complex surface
Authors: Barbosa F. V. , Teixeira S. F. C. F. , Teixeira J. C. F.
Published: August 2023

Submerged and confined multiple jet impingement is widely implemented in cooling applications since it provides high heat transfer coefficients and uniformity over the target plate. Its performance depends on several variables that make it complex and difficult to control. To understand the physical phenomena and characterize the flow field, an in-depth study, using Particle Image Velocimetry (PIV) technique and an heat flux sensor, is conducted in this study. The PIV provides relevant data, but the accuracy of the measurements depends on an effective experimental setup and a careful selection of the most appropriate tracer particles. Therefore, this work presents the purpose-built experimental apparatus and comprises an analysis of the efficiency of different seeding particles. The results demonstrate that olive oil particles are appropriate to track turbulent flows since particles with about 1 μm diameter are obtained by the seeding generator. PIV measurements highlight the complexity of the jet flow impinging on a step surface, which induces a strong flow reversal that affects the jet flow development and the interaction with the adjacent jets. The large-scale structures induced in the vicinity of the target plate are captured by the PIV, as well as the strong fountain flows generated between the adjacent jets. Compared with the flat geometry, the turbulence intensity at the central jet is around 25% higher for the 1 D step, while for the 2 D step, this increase reaches 7.5%. The increased turbulence intensity leads to an heat transfer enhancement. For the 2 D step plate, the Nusselt number recorded is 25% greater than the flat plate. Through this study, relevant insights for several engineering applications that use multiple jet impingement are provided, highlighting that the combination of PIV and heat flux sensors are appropriate to characterize the jet’s flow dynamics and the heat transfer of this complex process.
The microtubule signature in cardiac disease: etiology, disease stage, and age dependency
Authors: Algül Sıla , Dorsch Larissa M. , Sorop Oana , Vink Aryan , Michels Michelle , dos Remedios Cristobal G. , Dalinghaus Michiel , Merkus Daphne , Duncker Dirk J. , Kuster Diederik W. D. , van der Velden Jolanda
Published: August 2023

Employing animal models to study heart failure (HF) has become indispensable to discover and test novel therapies, but their translatability remains challenging. Although cytoskeletal alterations are linked to HF, the tubulin signature of common experimental models has been incompletely defined. Here, we assessed the tubulin signature in a large set of human cardiac samples and myocardium of animal models with cardiac remodeling caused by pressure overload, myocardial infarction or a gene defect. We studied levels of total, acetylated, and detyrosinated α-tubulin and desmin in cardiac tissue from hypertrophic (HCM) and dilated cardiomyopathy (DCM) patients with an idiopathic (n = 7), ischemic (n = 7) or genetic origin (n = 59), and in a pressure-overload concentric hypertrophic pig model (n = 32), pigs with a myocardial infarction (n = 28), mature pigs (n = 6), and mice (n = 15) carrying the HCM-associated MYBPC32373insG mutation. In the human samples, detyrosinated α-tubulin was increased 4-fold in end-stage HCM and 14-fold in pediatric DCM patients. Acetylated α-tubulin was increased twofold in ischemic patients. Across different animal models, the tubulin signature remained mostly unaltered. Only mature pigs were characterized by a 0.5-fold decrease in levels of total, acetylated, and detyrosinated α-tubulin. Moreover, we showed increased desmin levels in biopsies from NYHA class II HCM patients (2.5-fold) and the pressure-overload pig model (0.2–0.3-fold). Together, our data suggest that desmin levels increase early on in concentric hypertrophy and that animal models only partially recapitulate the proliferated and modified tubulin signature observed clinically. Our data warrant careful consideration when studying maladaptive responses to changes in the tubulin content in animal models.

Graphical Abstract
The Helmholtz legacy in color metrics: Schrödinger’s color theory
Authors: Roberti Valentina , Peruzzi Giulio
Published: August 2023

This study is a continuation of the authors’ previous work entitled “Helmholtz and the geometry of color space: gestation and development of Helmholtz’s line element” (Peruzzi and Roberti in Arch Hist Exact Sci.https://doi.org/10.1007/s00407-023-00304-2, 2023), which provides an account of the first metrically significant model of color space proposed by the German polymath Hermann von Helmholtz in 1891–1892. Helmholtz’s Riemannian line element for three-dimensional color space laid the foundation for all subsequent studies in the field of color metrics, although it was largely forgotten for almost three decades from the time of its first publication. The rediscovery of Helmholtz’s masterful work was due to one of the founders of quantum mechanics, Erwin Schrödinger. He established his color metric in three extended papers submitted in 1920 to theAnnalen der Physik. Two memoirs were devoted to the so-calledlower color metric,which laid the basis for the development of hishigher color metric, exposed in the last paper. Schrödinger’s approach to the geometry of color space has been taken as a starting point for future elaborations of color metrics and allows a close examination of the current assumptions about the analysis of color-matching data. This paper presents an overall picture of Schrödinger’s works on color. His color theory developed a tradition first inaugurated by Newton and Young, and which acquired strong scientific ground with Grassmann’s, Maxwell’s, and Helmholtz’s contributions in the 1850s. Special focus will be given to Schrödinger’s account of color metric, which responded directly to Helmholtz’s hypothesis of a Riemannian line element for color space.
Impact of empiric antibiotic therapy on the clinical outcome of acute calculous cholecystitis
Authors: de Miguel-Palacio Maite , González-Castillo Ana-María , Membrilla-Fernández Estela , Pons-Fragero María-José , Pelegrina-Manzano Amalia , Grande-Posa Luis , Morera-Casaponsa Ricard , Sancho-Insenser Juan-José
Published: August 2023

Purpose

Although mortality and morbidity of severe acute calculous cholecystitis (ACC) are still a matter of concern, the impact of inadequate empirical antibiotic therapy has been poorly studied as a risk factor. The objective was to assess the impact of the adequacy of empirical antibiotic therapy on complication and mortality rates in ACC.

Methods

This observational retrospective cohort chart-based single-center study was conducted between 2012 and 2016. A total of 963 consecutive patients were included, and pure ACC was selected. General, clinical, postoperative, and microbiological variables were collected, and risk factors and consequences of inadequate treatment were analyzed.

Results

Bile, blood, and/or exudate cultures were obtained in 76.3% of patients, more often in old, male, and severely ill patients (P < 0.001). Patients who were cultured had a higher overall rate of postoperative complications (47.4% vs. 29.7%; P < 0.001), as well as of severe complications (11.6% vs. 4.7%; P = 0.008). Patients with positive cultures had more overall complications (54.8% vs. 39.6%; P = 0.001), more severe complications (16.3% vs. 6.7%; P = 0.001), and higher mortality rates (6% vs. 1.9%; P = 0.012). Patients who received inadequate empirical antibiotic therapy had a fourfold higher mortality rate than those receiving adequate therapy (n = 283; 12.8% vs. 3.4%; P = 0.003). This association was especially marked in severe ACC TG–III patients (n = 132; 18.2 vs. 5.1%; P = 0.018) and remained a predictor of mortality in a binary logistic regression (OR 4.4; 95% CI 1.3–15.3).

Conclusion

Patients with positive cultures developed more complications and faced higher mortality. Adequate empirical antibiotic therapy appears to be of paramount importance in ACC, particularly in severely ill patients.
Treatment patterns in stage III non‑small‑cell lung cancer patients: a population‑based study using German cancer registry data
Authors: Bedir Ahmed , Mehrotra Sneha , Gnüchtel Jessica , Vordermark Dirk , Medenwald Daniel
Published: August 2023

Purpose

Lung cancer remains the leading cause of cancer-related mortality worldwide, mostly due to delayed diagnosis. The objective of this study is to examine the treatment patterns and overall survival (OS) outcomes in a cohort of patients diagnosed with stage III non-small cell lung cancer (NSCLC) over a period of 12 years in Germany.

Methods

This retrospective study is based on German cancer registry data and included 14,606 stage III NSCLC patients diagnosed during 2007–2018. Three time-periods were defined according to the availability of advanced diagnostic and treatment strategies (2007–2010 low availability era (LAE), 2011–2014 transition era (TE), 2015–2018 modern era (ME)). Patients were categorized according to the treatment they received during those eras. Kaplan–Meier curves and multivariate Cox proportional hazards models were used to investigate the association between being diagnosed during a certain era and survival. The hazard ratio (HR) estimates were reported along with the 95% confidence interval (CI).

Results

The median OS rose from 16 months in the LAE to 22 months in the ME. The HR for patients diagnosed and treated in the ME was estimated to be [0.78; 95% CI (0.74–0.83)] compared to those diagnosed and treated in LAE. The benefit was most evident for patients treated by radiotherapy and chemotherapy [HR 0.73 95% CI (0.66–0.82)].

Conclusion

This study highlights the importance of diagnostic and treatment advances in improving outcomes for lung cancer patients. Further studies are needed to assess progress in survival rates with current immunotherapy integration.
Programmable (proSA®) vs. fixed (SHUNTASSISTANT®) gravitational valves in pediatric patients with hydrocephalus: a 16-year retrospective single-center comparative study with biomechanical analysis
Authors: Issa Mohammed , Paggetti Filippo , von Hardenberg August , Miethke Christoph , Unterberg Andreas W. , El Damaty Ahmed
Published: August 2023

Purpose

In pediatric hydrocephalus (HC) treatment, programmable gravitational valves offer greater flexibility to manage overdrainage during children’s growth. However, it remains unclear whether these devices provide better outcomes rather than their precursors. The study assessed the benefit from programmability of gravitational valve, i.e., programmable-SHUNTASSISTANT (proSA®) vs. SHUNTASSISTANT® (SA®).

Methods

Clinical records and imaging of pediatric patients with hydrocephalus of non-tumoral etiology treated with fixed (SA®) or programmable (proSA®) gravitational valves between January 2006 and January 2022 were analyzed in a retrospective single-center study. Valve survival was compared in relation to age and etiology. Lately explanted valves received biomechanical analysis.

Results

A total of 391 gravitational valves (254 SA® and 137 proSA®) were inserted in 244 patients (n = 134 males). One hundred thirty-three SA® (52.4%) and 67 proSA® (48.9%) were explanted during a follow-up of 81.1 ± 46.3 months. Valve survival rate at 1 and 5 years with proSA® was 87.6% and 60.6% compared to 81.9% and 58.7% with SA®, with mean survival time 56.4 ± 35.01 and 51.4 ± 43.0 months, respectively (P = 0.245). Age < 2 years at implantation correlated with significantly lower valve survival rates (P < 0.001), while HC etiology showed no significant impact. Overdrainage alone accounted for more SA® revisions (39.8% vs. 3.1%, P < 0.001), while dysfunctions of the adjustment system represented the first cause of valve replacement in proSA® cohort (45.3%). The biomechanical analysis performed on 41 proSA® and 31 SA® showed deposits on the valve’s internal surface in 97.6% and 90.3% of cases.

Conclusion

Our comparative study between proSA® and SA® valves in pediatric HC demonstrated that both valves showed similar survival rates, regardless of etiology but only with young age at implantation. The programmability may be beneficial in preventing sequelae of chronic overdrainage but does not reduce need for valve revision and proSA® valve should be considered in selected cases in growing children older than 2 years.
Salivary pellicle modulates biofilm formation on titanium surfaces
Authors: Martínez-Hernández Miryam , Reyes-Grajeda Juan Pablo , Hannig Matthias , Almaguer-Flores Argelia
Published: August 2023

Objectives

The present study aimed to evaluate the potential of the salivary pellicle (SP) formed on titanium (Ti) surfaces to modulate the formation of a biofilm composed of Streptococcus gordonii, Actinomyces naeslundii, Fusobacterium nucleatum, and Porphyromonas gingivalis.

Materials and methods

Ti substrates were incubated for 2 h with a pool of saliva samples obtained from 10 systemically and periodontally healthy subjects. Enamel substrates were included as a biological reference. Scanning electron microscopy (SEM) and Raman spectroscopy analysis were used to analyze the formation of the salivary pellicle. After the SP formation, the surfaces were incubated for 12 h with a mix of Streptococcus gordonii, Actinomyces naeslundii, Fusobacterium nucleatum, and Porphyromonas gingivalis. The number of bacterial cells attached to each surface was determined by the XTT assay while bacterial viability was analyzed by fluorescence microscopy using the LIVE/DEAD® BacLightTM kit.

Results

The SEM and Raman spectroscopy analysis confirmed the presence of a salivary pellicle formed on the tested surfaces. Regarding the biofilm formation, the presence of the SP decreases the number of the bacterial cells detected in the test surfaces, compared with the uncover substrates. Even more, the SP-covered substrates showed similar bacterial counts in both Ti and enamel surfaces, meaning that the physicochemical differences of the substrates were less determinant than the presence of the SP. While on the SP-uncover substrates, differences in the bacterial adhesion patterns were directly related to the physicochemical nature of the substrates.

Conclusions

The salivary pellicle was the main modulator in the development of the biofilm consisting of representative oral bacteria on the Ti substrates.

Clinical relevance

The results of this study provide valuable information on the modulatory effect of the salivary pellicle on biofilm formation; such information allows us to understand better the events involved in the formation of oral biofilms on Ti dental implants.
The working angle in low-abrasive air polishing has an influence on gingival damage—an ex vivo porcine model
Authors: Weusmann Jens , Deschner James , Keppler Christopher , Imber Jean-Claude , Cores Ziskoven Pablo , Schumann Sven
Published: August 2023

Objectives

To investigate the influence of instrumentation angle during low-abrasive air polishing (LAA) on the oral gingiva using an ex vivo porcine model.

Material and methods

Six tissue samples from each of 14 porcine mandibles were randomly selected and instrumented. Two different LAA powders (glycine 25 μm, tagatose 15 μm) were investigated. An application angle of either 30–60° or 90° was selected. Gingival specimens from different mandibles served as untreated references. Gingival biopsies were examined by scanning electron microscopy and paraffin histology for tissue destruction using a five-level scale.

Results

LAA caused significantly less tissue damage at a 90° angle than at a 30–60° angle. This effect was seen in both the glycine-based powder arms (p = 0.002, p = 0.046) and the tagatose-based powder arms (p = 0.003, p = 0.011). However, at identical working angles, the two powders did not show significant differences in terms of gingival erosion (p = 0.79 and p = 0.57; p = 0.91 and p = 0.78, respectively).

Conclusions

LAA may cause less tissue damage at an application angle of 90°. Consequently, it seems advisable to air-polish the soft tissue as perpendicularly as possible. Additionally, glycine and tagatose LAA powders do not seem to differ in concern of soft tissue damage.

Clinical relevance

Within the limitations of this ex vivo animal model, this study argues for an application that is as close as possible to the 90° angle intending to minimize soft tissue damage. Manufacturer specifications, however, mainly request applications deviating from the right angle. In order to work in interdental areas using LAA safely, the use of subgingival nozzles might be considered.
Crack growth based tooth root life prediction model—an influence quantity analysis
Authors: Lövenich Johannes , Zalfen Moritz , Mevissen Dieter , Brimmers Jens , Brecher Christian
Published: August 2023

One of the key challenges of epicyclic gearboxes in turbo gearbox applications is the high number of load cycles reached by the gearbox components. Standards such as ISO 6336 deliver design guidelines for bending strength up to a limiting number of NG = 3∙106 and AGMA up to 107 load cycles which is far less than the expected lifetime of turbo gearbox applications.

To design gears for geared turbofans safely and weight-optimized, the tooth root load capacity in the very high cycle fatigue (VHCF) range must be known as precisely as possible. Most VHCF SN-curve concepts show a continuously decreasing fatigue strength, so that a consideration of a constant fatigue strength level does not meet the material behavior. A life prediction model can be used to determine the specific load that can be carried for each number of load cycles.

In this paper, the nasgro crack growth equation is applied to gears to determine the tooth root life in the VHCF range. A lifetime for surface and sub-surface induced fractures is calculated, resulting in a stepped SN-curve. Most of the cycles until fracture occur during crack initiation and micro crack growth, while the macro crack is a small part of the total number of load cycles until tooth root fracture. The nasgro equation is able to represent micro and macro crack growth and is extended by further approaches to the threshold of crack initiation Kth, which also consider the characteristics of short and long crack growth. In addition, the tooth root stress depth curve (via FEM), the hardness depth curve, the residual stress depth curve and the defect distribution will be included in the life-time prediction as important influencing variables of the VHCF tooth root load capacity. The influence of the inputs is determined in an influence quantity analysis. In the future the lifetime prediction model is validated with rig tests up to the VHCF range.