bluuebunny/crossref_metadata_2025 huggingface dataset:
Einige exotische Gehölze in den Interglazialfloren der Mitteleuropäischen Florenregion
Authors: Mai Dieter Hans
Published: August 2024

Aus interglazialen und interstadialen Ablagerungen im Süden der DDR werden nach Früchten, Samen und Blättern einige exotische Gehölzarten neu beschrieben. Der mitteleuropäischen Florenregion fremd sind gegenwärtig Crataegus nigra Waldst. et Kit., C. pentagyna Waldst. et Kit., Mespilus germanica L., Picea omorika (Panč.) Purk., Pterocarya fraxinifolia (Lam.) Spach und Swida alba (L.) Opiz. Im Westen ihres Areals erreichen die subatlantische Florenprovinz Acer monspessulanum L., Vitis vinifera L. ssp. sylvestris (C. C. Gmel.) Berger, im Osten die sarmatische Florenprovinz Acer tataricum L., randlich auch die zentraleuropäische Provinz Prunus mahaleb L. und Quercus pubescens Willd. Diese regionalen Exoten im Sinne der Reidschen Definition charakterisieren trotz ihrer Seltenheit in erheblichem Maße die fossilen Waldgesellschaften. Ihre Chorogenese und Soziogenese wird untersucht. Alle diese Gehölzarten haben ihre historischen Wurzeln in den spättertiären Mixed Mesophytic Forests in Europa. Ihr pliozänes Vorkommen ist in jedem Falle gesichert. Für die Waldvegetation der Interglaziale und Interstadiale der mitteleuropäischen Region ergibt sich der Nachweis folgender (thermophiler) Assoziationen:

Aceri monspessulani — Quercetum petraeae‐roboris

Aceri tatarici — Quercetum pubescenti‐roboris

Aceri tatarici — Tilietum

Buxo — Quercetum pubesccntis

Fraxino — Ulmetum

Larici — Piceetum omorikae

Piceo omorikae — Alnetum glutinosae

Pruno mahalebis — Quercetum pubescentis

Pterocaryo — Alnetum glutinosae

Quercetum pubescentis‐petraeae.
L'étude cénotaxonomique des forêts de résineaux (la classe de Vaccinio‐Piceetea Br.‐Bl. 1939) des Carpates de la Roumania
Authors: Sanda V. , Popescu A. , Peicea I.
Published: August 2024

Vorliegende Arbeit untersucht die Struktur der Assoziationen der Klasse Vaccinio‐Piceetea aus den rumänischen Karpaten. Es werden die topoklimatischen und edaphischen Bedingungen betrachtet, die zur Differenzierung in zahlreiche zönotaxonomische Gruppierungen beigetragen haben. Hier spielen neben den Gebüschen von Vaccinium myrtillus und V. vitis‐idaea Gras‐ und Moosteppiche eine gewichtige Rolle. Für jede Assoziation werden die Synonyme, die floristische Zusammensetzung und Struktur gegeben sowie die Einheiten niederen taxonomischen Ranges erwähnt.
Les grandes unites phytosociologiques au Mali Central Deuxieme partie: les milieux secs
Authors: Aberlin Jean‐Pierre
Published: August 2024

Resumé

De nombreux travaux effectués durant ces 20 dernières années par les agrostologues de l'Institut d:Elevage et de Médecine Vétérinaire des pays Tropicaux (I.E.M.V.T., Maisons Alfort) ont conduit á définir, en République du Mali, divers groupements végétaux.

Un séjour de quatre années consécutives (1974 à 1977) a permis, par traitement informatique des données recueillies, de nommer diverses unités phytosociologiques dans une région du Mali central et ceci dans les milieux secs et humides.

Seules les unités se trouvant dans les milieux secs seront présentées dans cet article; elles sont formées par: un Ordre, deux Alliances, deux Sous‐Alliances et neuf associations.
Experimentelle Untersuchungen über die infraspezifische Struktur von Chenopodium album L. sowie: Untersuchungen an Chenopodium suecicum J. Murr
Authors: Jüttersonke Barbara , Arlt Klaus
Published: August 2024

Die vorgestellte Bearbeitung ergab sich aus der Notwendigkeit, eine praktisch anwendbare Taxonomie für eine erfolgreiche Agro‐Ökosystem‐Modellierung sowie für die Lösung von Problemen der Erforschung und Bekämpfung herbizidresistenter Unkräuter zu schaffen. Gegenstand der Untersuchungen war das Taxon Chenopodium album L. ssp. album var. album (sensu Aellen 1960). Durch mehrjährige Kulturversuche mit Nachkommenschaften ausgewählter Herkünfte, die hauptsächlich in der DDR gesammelt wurden, konnte die genetische Stabilität wichtiger Merkmale und deren Modifizierbarkeit durch Umweltfaktoren bewertet werden. Die Infloreszenzformen sind relativ stabil; auch unter differenzierten Temperatur‐ und Tageslängenbehandlungen wurden ihre Grundmuster nicht wesentlich verändert. Sie wurden daher als Basismerkmale für ein neues System verwendet, das geeignet ist, die Formenvielfalt des bearbeiteten Taxons hierarchisch zu ordnen und Beziehungen zwischen den Taxa zu zeigen. Den beschriebenen Formen und Subformen sind die Subvarietäten album und cymigerum übergeordnet. Untersuchungen über die Variabilität des Ch. suecicum J. Murr ergaben ebenfalls signifikante Unterschiede, die aber eine intensivere taxonomische Bearbeitung nicht ermöglichten. Erhebungen über die Verbreitung der beschriebenen Taxa des Ch. album var. album sowie des Ch. suecicum zeigten, daß Bindungen einiger Taxa an bestimmte Standorttypen, Klimagebiete und Kulturen bestehen.
Nature of ergastic substances in some angiospermic seeds — V*
Authors: Gill L. S. , Abili M. A.
Published: August 2024

Seeds of 200 species of 17 angiospermic families were examined for the presence of alkaloids, cellulose, fats and oils, inulin, protein, starch granules and tannins.

Alkaloids, cellulose, fats and oils, inulin, protein and tannins are found to be of sporadic occurrence in taxa studied. Cellulose, fats and oils and inulin were found to be present in all taxa studied. Of the 200 taxa studied, only 17 taxa belonging to 2 families (Caryophyllaceae, Leguminosae) are found to contain starch grains. However, the starch grains present are restricted to a particular type of habit, mainly the herbaceous habit. In general, arborescent taxa lack starch grains. 167 species distributed in 15 families investigated for ergastic substances are reported here for the first time.
Attenuation of chromium (VI) and arsenic (III)‐induced oxidative stress and hepatic apoptosis by phloretin, biochanin‐A, and coenzyme Q10 via activation of SIRT1/Nrf2/HO‐1/NQO1 signaling
Authors: Tripathi Swapnil , Parmar Dharati , Raval Samir , Mishra Rajeev , Singh Gyanendra
Published: August 2024

Heavy metal contamination is an alarming concern on a global scale, as drinking tainted water significantly increases human susceptibility to heavy metals. In a realistic scenario, humans are often exposed to a combination of harmful chemicals rather than a single toxicant. Phloretin (PHL), biochanin‐A (BCA), and coenzyme Q10 (CoQ10) are bioactive compounds owning plentiful pharmacological properties. Henceforth, the current research explored the putative energizing effects of selected nutraceuticals in combined chromium (Cr) and arsenic (As) intoxicated Swiss albino mice. Potassium dichromate (75 ppm) and sodium meta‐arsenite (100 ppm) were given in the drinking water to induce hepatotoxicity, conjugated with PHL and BCA (50 mg/kg each), and CoQ10 (10 mg/kg) intraperitoneally for 2 weeks. After the statistical evaluation, it was observed that the hepato‐somatic index, metal load, and antioxidant activity (lipid peroxidation and protein carbonyl content) increased along with the concomitant decrease in the antioxidants (catalase, glutathione‐S‐transferase, superoxide dismutase, reduced glutathione, and total thiol) in the Cr and As intoxicated mice. Additionally, light microscopy observations, DNA breakages, decreased silent information regulator 1 (SIRT1), nuclear factor (erythroid‐derived 2)‐like 2 (Nrf2), heme oxygenase (HO‐1), and NAD(P)H quinone dehydrogenase 1 (NQO1) gene expressions, together with stimulated apoptotic cell death manifested by the increased expressions of caspase 8 and caspase 3, thus, proved consistency with the aforementioned outcomes. Importantly, the treatment with nutraceuticals not only restored the antioxidant activity but also favorably altered the expressions of SIRT1, Nrf2, HO‐1, and NQO1 signaling and apoptosis markers. These findings highlight the crucial role of the PHL, BCA, and CoQ10 combination in reducing Cr and As‐induced hepatotoxicity in mice. By averting the triggered apoptosis in conjunction with oxidative stress, this combination increases the SIRT1, Nrf2, HO‐1, and NQO1 signaling, thereby reassuringly maintaining the cellular equilibrium.
Energy and spectroscopic parameters of neutral and cations isomers of the CnH2 (n = 2–6) families using high‐level ab‐initio approaches
Authors: Díaz Soto Lenin J. , Oliveira Ricardo R. , Baptista Leonardo , da Silveira Enio F. , Nascimento Marco Antonio Chaer
Published: August 2024

Cationic species, previously detected from ion‐induced desorption of solid methane by plasma desorption mass spectrometry (PDMS), and neutral species, are investigated using high‐level ab‐initio approaches. From a set of 25 cationic and 26 neutral structures belonging to CnH2 (n = 2–6) families, it was obtained the energy, rotational constants, harmonic vibrational frequency, charge distribution and excitation energies. The ZPVE‐corrected energies, at CCSD(T)‐F12; CCSD(T)‐F12/RI/(cc‐pVTZ‐F12, cc‐pVTZ‐F12‐CABS, cc‐pVQZ/C) (n = 2–5) and CCSD(T)/cc‐pVTZ (n = 6) levels, reveal that the topology of the most stable isomer vary with n and the charge. Out of 674 harmonic frequencies, those with maximum intensity are generally in the 3000–3500 cm−1 range. Analysis of 169 vertical transition energies calculated with the EOM‐CCSD approach, suggest three C6H2 species as potential carriers of the diffuse interstellar bands (DIB). Systematic comparison of properties between neutral and cationic species can assist in the structural description of complex matrices.
Impact of dental school critical thinking demonstrations carryover to practice: Survey of 5‐year graduates
Authors: Johnsen David C. , Marchini Leonardo , Syrbu John , Howe Brian J. , Hartshorn Jennifer E. , Desai Jhanvi , Butali Azeez , Shi Wei
Published: August 2024

Introduction

Little literature exists on graduates’ application to practice for explicit critical thinking skills learned in dental school.

Purposes

Discern the (1) degree to which graduates apply explicit critical thinking skillsets in practice; (2) degree of adaptation of critical thinking skillsets to practice; (3) frequency of use for critical thinking skillsets in practice; and (4) perceptions to improve critical thinking learning guidance in dental school.

Methods

Five critical thinking exercises/skillsets were selected that had been in place over 5 years with at least one paper: geriatrics, treatment planning, technology decision making, ethics, evidence‐based dentistry; each followed concepts from an emulation model in critical thinking. Electronic survey administered in 2023/2024 to alumni graduated in the last 5 years.

Results

Of 98 (from 320 distributed) returned, 56 completed the entire survey. Dental school experiences positively influenced use of critical thinking skills in practice. On a five‐point scale, mostly 4s and 5s were reported for “…benefit your thinking.” Fifty‐three percent reported “using ideas from the exercise and developed my own thought processes,” 35% reported “using the thought process largely as offered in the college” and 5% reported “do not use the exercise.” Sixty percent reported using the skillsets hourly or daily. With minor variations all skillsets were reported positively for use in practice.

Conclusions

A positive influence of critical thinking skills was gained from the college experience with explicit positive impact for each of the five critical thinking experiences. The questions may be a model for future follow‐up studies of explicit dental school critical thinking exercises.
Out of the shadow: Encouraging online registration of micro and small businesses through a randomized controlled trial
Authors: Dong Sarah Xue , Meisari Dewi , Rinaldi Banu
Published: August 2024

This paper presents the findings of a large‐scale randomized controlled field trial that tests the interest of informal businesses in free and online business registration. In collaboration with the Indonesian government, we designed a free and easy to use online registration portal for small businesses and sent WhatsApp or text messages to around 50 000 businesses to inform them about this new registration portal. We find that sending three rounds of short WhatsApp or text messages resulted in 3.4% of recipients clicking the registration link in the messages. Only 0.1% of recipients registered through the portal. Different phrasing of messages results in different click rate, different registration rate, and different rates the sender's number is blocked. Neutral message performs the best, followed by message that emphasizes that registration is easy. Message that appeals to people's patriotic feelings or message that emphasizes that registration is free performs the last.
Assessment of Tumor Cell Invasion and Radiotherapy Response in Experimental Glioma by Magnetic Resonance Elastography
Authors: Fels‐Palesandro Hannah , Heuer Sophie , Boztepe Berin , Streibel Yannik , Ungermann Johannes , Pan Chenchen , Scheck Jonas G. , Fischer Manuel , Sturm Volker J. , Azorín Daniel D. , Karimian‐Jazi Kianush , Annio Giacomo , Abdollahi Amir , Weidenfeld Ina , Wick Wolfgang , Venkataramani Varun , Heiland Sabine , Winkler Frank , Bendszus Martin , Sinkus Ralph , Breckwoldt Michael O. , Schregel Katharina
Published: August 2024

Background

Gliomas are highly invasive brain neoplasms. MRI is the most important tool to diagnose and monitor glioma but has shortcomings. In particular, the assessment of tumor cell invasion is insufficient. This is a clinical dilemma, as recurrence can arise from MRI‐occult glioma cell invasion.

Hypothesis

Tumor cell invasion, tumor growth and radiotherapy alter the brain parenchymal microstructure and thus are assessable by diffusion tensor imaging (DTI) and MR elastography (MRE).

Study Type

Experimental, animal model.

Animal Model

Twenty‐three male NMRI nude mice orthotopically implanted with S24 patient‐derived glioma cells (experimental mice) and 9 NMRI nude mice stereotactically injected with 1 μL PBS (sham‐injected mice).

Field Strength/Sequence

2D and 3D T2‐weighted rapid acquisition with refocused echoes (RARE), 2D echo planar imaging (EPI) DTI, 2D multi‐slice multi‐echo (MSME) T2 relaxometry, 3D MSME MRE at 900 Hz acquired at 9.4 T (675 mT/m gradient strength).

Assessment

Longitudinal 4‐weekly imaging was performed for up to 4 months. Tumor volume was assessed in experimental mice (n = 10 treatment‐control, n = 13 radiotherapy). The radiotherapy subgroup and 5 sham‐injected mice underwent irradiation (3 × 6 Gy) 9 weeks post‐implantation/sham injection. MRI‐/MRE‐parameters were assessed in the corpus callosum and tumor core/injection tract. Imaging data were correlated to light sheet microscopy (LSM) and histology.

Statistical Tests

Paired and unpaired t‐tests, a P‐value ≤0.05 was considered significant.

Results

From week 4 to 8, a significant callosal stiffening (4.44 ± 0.22 vs. 5.31 ± 0.29 kPa) was detected correlating with LSM‐proven tumor cell invasion. This was occult to all other imaging metrics. Histologically proven tissue destruction in the tumor core led to an increased T2 relaxation time (41.65 ± 0.34 vs. 44.83 ± 0.66 msec) and ADC (610.2 ± 12.27 vs. 711.2 ± 13.42 × 10−6 mm2/s) and a softening (5.51 ± 0.30 vs. 4.24 ± 0.29 kPa) from week 8 to 12. Radiotherapy slowed tumor progression.

Data Conclusion

MRE is promising for the assessment of key glioma characteristics.

Evidence Level

NA

Technical Efficacy

Stage 2
The intestinal microbiome of infants with cow's milk‐induced FPIES is enriched in taxa and genes of enterobacteria
Authors: Castro Ana M. , Sabater Carlos , Gutiérrez‐Díaz Isabel , Navarro Sandra , Rodriguez Silvia , Molinos Cristina , Jiménez Santiago , Claver Angela , Espin Beatriz , Domínguez Gloria , Coronel Cristóbal , Toyos Paula , Sariego Lydia , Fernández Porfirio , Perez David , Margolles Abelardo , Díaz Juan J. , Delgado Susana
Published: August 2024

Objectives

Food protein‐induced enterocolitis syndrome (FPIES) is a severe type of non‐IgE (immunoglobulin E)‐mediated (NIM) food allergy, with cow's milk (CM) being the most common offending food. The relationship between the gut microbiota and its metabolites with the inflammatory process in infants with CM FPIES is unknown, although evidence suggests a microbial dysbiosis in NIM patients. This study was performed to contribute to the knowledge of the interaction between the gut microbiota and its derived metabolites with the local immune system in feces of infants with CM FPIES at diagnosis.

Methods

Twelve infants with CM FPIES and a matched healthy control group were recruited and the gut microbiota was investigated by 16S amplicon and shotgun sequencing. Fatty acids (FAs) were measured by gas chromatography, while immune factors were determined by enzyme‐linked immunosorbent assay and Luminex technology.

Results

A specific pattern of microbiota in the gut of CM FPIES patients was found, characterized by a high abundance of enterobacteria. Also, an intense excretion of FAs in the feces of these infants was observed. Furthermore, correlations were found between fecal bifidobacteria and immune factors.

Conclusion

These fecal determinations may be useful to gain insight into the pathophysiology of this syndrome and should be taken in consideration for future studies of FPIES patients.
Consumer Trends Reflected in the Contents of the Pediatric Esophagus: A 20‐Year Review
Authors: Xiao Jenny B. , Siu Jennifer M. , Propst Evan J. , Wolter Nikolaus E.
Published: August 2024

Objectives

To evaluate epidemiological trends of pediatric esophageal foreign body (EFB) ingestion over two decades.

Methods

A retrospective analysis was performed using data from the National Electronic Injury Surveillance System (NEISS) database for children <18 years who presented to a United States Emergency Department (ED) with EFB between 2003 and 2022. Number of cases and type of EFB were recorded. Rates of EFBs over time were analyzed via linear regression.

Results

A total of 52,315 EFB cases were identified over the 20‐year period, with a national estimate of 1,589,325 cases. The most frequently ingested objects were coins (37.6%), toys (13.5%), and batteries (6.8%). Overall incidence of EFB ingestion increased from 7.3 to 14.2/10,000 children from 2003 to 2022 (R2 = 0.8, p < 0.0001). Incidence of coin ingestion increased from 3 to 4.5/10,000 children (R2 = 0.06, p = 0.335) but represented a smaller proportion of all EFB over time (66% in 2003 versus 43% in 2022). Incidence of magnet, battery, and toy ingestion have increased from 0.3 to 1.0/10,000 (R2 = 0.9, p < 0.0001), 0.3 to 1/10,000 (R2 = 0.7, p < 0.0001), and 0.6 to 2.3/10,000 (R2 = 0.8, p < 0.0001) children, respectively, between 2003 and 2022. The proportion of magnet, battery, and toy ingestion have increased over time (3.2%, 6.5%, and 11.8%, respectively, in 2003 to 11.4%, 11.7%, and 22.2%, respectively, in 2022).

Conclusion

Magnet, battery, and toy ingestion have increased significantly in the past two decades, while the proportion of coin ingestion has decreased. This trend may reflect shifts within the consumer market and increased availability of electronics concurrent with the adoption of digital currency.

Level of Evidence

4 Laryngoscope, 2024
Novel Acryloylated and Methacryloylated Nanocellulose Derivatives with Improved Mucoadhesive Properties
Authors: Atakhanov Abdumutolib A. , Ashurov Nurbek Sh. , Kuzieva Makhliyo M. , Mamadiyorov Burhon N. , Ergashev Doniyor J. , Rashidova Sayyora Sh. , Khutoryanskiy Vitaliy V.
Published: August 2024

In this work, three nanocellulose derivatives are synthesized with the aim of preparing new mucoadhesive materials. Nanocellulose is reacted with glycidyl methacrylate in dimethylsulphoxide, and with acryloyl and methacryloyl chloride in dimethylacetamide in the presence of 4‐(N,N‐dimethylamino)pyridine as a catalyst. These reactions are carried out under heterogeneous conditions, and the reaction products are characterized using various spectroscopic techniques, X‐ray diffraction, atomic force microscopy, and thermogravimetric analysis. The Fourier‐transform infrared spectra showed all the characteristic absorption bands typical for cellulose and also new peaks at 1720 cm−1 for the carbonyl group (C═O) and 1639, 812 cm−1 for the double bond (C═C). It is established that the crystal structure of the nanocellulose is slightly changed with derivatisation and the thermal stability of these derivatives increased. Mucoadhesive properties of nanocellulose and its derivatives is evaluated using the tensile test, rotating basket method, and fluorescence flow‐through method. The retention of these polymers is evaluated on sheep oral mucosal tissue ex vivo using artificial saliva. Test results demonstrated that the new derivatives of nanocellulose have improved mucoadhesive properties compared to the parent nanocellulose.
Substrates with Tunable Hydrophobicity for Optimal Cell Adhesion
Authors: Snyder Yuriy , Todd Mary , Jana Soumen
Published: August 2024

Electrospinning is a technique used to create nano/micro‐fibrous materials from various polymers for biomedical uses. Polymers like polycaprolactone (PCL) are commonly used, but their hydrophobic properties can limit their applications. To enhance hydrophilicity, nonionic surfactants such as sorbitane monooleate (Span80) and poloxamer (P188) can be added to the PCL electrospinning solution without altering its net charge density. These additions enable the successful production of PCL/P188 and PCL/Span80 fibrous substrates. In this study, P188 and Span80 are incorporated into the PCL solutions; they are successfully electrospun into PCL/P188 and PCL/Span80 substrates, respectively. PCL/P188 substrates show that until a specific P188 concentration, fiber and pore sizes are similar to PCL substrates. However, exceeding 0.30% P188 concentration enlarges fibers, impacting fiber uniformity at higher concentrations. Conversely, higher concentrations of Span80 result in thicker, less uniform fibers, indicating potential disruptions in the electrospinning process. Notably, both surfactants significantly improve substrate hydrophilicity, enhancing the adhesion and proliferation of fibroblasts, endothelial cells, and smooth muscle cells. P188, in particular, shows superior efficacy in promoting cell adhesion and growth at concentrations optimized for different cell types. Therefore, precise surfactant concentrations in the electrospinning solution can lead to the optimization of electrospun substrates for tissue engineering applications.
Reviewing mathematical models of sperm signaling networks
Authors: Priego Espinosa Daniel , Espinal‐Enríquez Jesús , Aldana Andrés , Aldana Maximino , Martínez‐Mekler Gustavo , Carneiro Jorge , Darszon Alberto
Published: August 2024

Dave Garbers’ work significantly contributed to our understanding of sperm's regulated motility, capacitation, and the acrosome reaction. These key sperm functions involve complex multistep signaling pathways engaging numerous finely orchestrated elements. Despite significant progress, many parameters and interactions among these elements remain elusive. Mathematical modeling emerges as a potent tool to study sperm physiology, providing a framework to integrate experimental results and capture functional dynamics considering biochemical, biophysical, and cellular elements. Depending on research objectives, different modeling strategies, broadly categorized into continuous and discrete approaches, reveal valuable insights into cell function. These models allow the exploration of hypotheses regarding molecules, conditions, and pathways, whenever they become challenging to evaluate experimentally. This review presents an overview of current theoretical and experimental efforts to understand sperm motility regulation, capacitation, and the acrosome reaction. We discuss the strengths and weaknesses of different modeling strategies and highlight key findings and unresolved questions. Notable discoveries include the importance of specific ion channels, the role of intracellular molecular heterogeneity in capacitation and the acrosome reaction, and the impact of pH changes on acrosomal exocytosis. Ultimately, this review underscores the crucial importance of mathematical frameworks in advancing our understanding of sperm physiology and guiding future experimental investigations.
Gradient‐induced vibrations and motion‐induced Lenz effects on conductive nonmagnetic orthopedic implants in MRI
Authors: Zilberti Luca , Curreli Cristina , Arduino Alessandro , Zanovello Umberto , Baruffaldi Fabio , Bottauscio Oriano
Published: August 2024

Purpose

To quantify the extent of gradient‐induced vibrations, and the magnitude of motion‐induced displacement forces (“Lenz effect”), in conductive nonmagnetic orthopedic prostheses.

Methods

The investigation is carried out through numerical simulations, for a 3 T scanner. For gradient‐induced torques and vibrations, a knee and a shoulder implant are considered, at dB/dt equal to 42 T/s (rms). For motion‐induced forces associated with the Lenz effect, a knee and a hip implant are studied, considering a patient who translates on the examination couch, or walks next to it.

Results

Gradient‐induced torques may be within the same order of magnitude as the worst case gravitational torque defined in the ASTM standards. However, for all investigated cases, they result to be lower. In vacuum, the extent of the corresponding vibration reduces with frequency. At the lowest investigated frequency (270 Hz), it keeps below 25 μm. For an implant partially embedded in bone, the extent of the vibration increases with frequency. Nevertheless, the displacement is far lower than the worst case observed in vacuum (negligible in contact with the bone; ˜1 μm or less where the implant emerges from the bone). The Lenz effect induced by the motion of the patient through the stationary magnetic field produces forces on the order of a few millinewtons (i.e., at least two orders of magnitude lower than the implant weight).

Conclusion

Comparing the results with mechanical loads caused by ordinary activities of daily living, and with the levels of tolerable micromotions, a good safety margin is confirmed.
Repairing of recycled hybrid carbon fiber laminates
Authors: Proietti Alice , Quadrini Fabrizio , Santo Loredana
Published: August 2024

Compression molded hybrid laminates have been manufactured by stacking 10 recycled epoxy‐based carbon fiber plies with interlaminar polyamide film of 50 μm thickness. At first, carbon fiber (CF) reinforced composites underwent thermo‐mechanical disassembly to obtain single composite CF plies. These plies, still impregnated with the waste cured resin, have been re‐assembled by interposing one or two sheets of the thermoplastic film in the lamination sequence. Neat laminates have been used for comparison. Samples of size 85 × 30 mm2 have been tested under bending load, and materials repairability has been evaluated under 2 consecutive repairing cycles that have been carried out by applying pressure and heat along the composite failure line. Even though the neat composite showed the best mechanical properties, after the first repairing cycle a drastic drop has been recorded with a reduction of the elastic modulus of 92.4%. On the other hand, the elastic modulus of the hybrid composites has been reduced of only 24% on average.

Highlights

Thermo‐mechanical disassembly is used to recycle epoxy carbon fiber composite.

Hybrid laminates are obtained by placing polyamide film between recycled plies.

Pressure and heat are applied along the composite failure line for repairing.

Hybrid composites repairing is carried out in comparison with neat materials.

Repaired hybrid laminates have a higher elastic modulus than neat once.
Engineering material from flexible food packaging waste: Property profile and feasibility
Authors: Várdai Róbert , Romsics Imre , Pregi Emese , Faludi Gábor , Móczó János , Pukánszky Béla
Published: August 2024

The goal of this project was to recycle the waste forming in the production of a flexible, multilayer food packaging film. The film consists of five layers, two polyamides containing three different polymers, a polyethylene and two adhesive layers of maleated polyethylene. The type of the components and the exact composition are not disclosed because they represent proprietary information. The key to recycling is the selection of an appropriate strategy and target product. In this case, glass fiber reinforced PA composites were produced with an acceptable property profile. The properties of the recycled product are comparable to those of commercial composites available on the market. The crucial question was the selection of the glass fiber grade with the appropriate sizing. The selection was further complicated by the possible interaction of the functionalized polymer with the sizing of the fiber. The implementation of the solution is feasible technologically, the properties of the product are comparable to those available on the market, and its price is very advantageous.

Highlights

An engineering material can be produced from flexible multilayer packaging waste.

The properties of the recycled product are comparable with those on the market.

The selection of the glass fiber is crucial for mechanical properties.

The solution is feasible technologically and the final price is competitive.
Lifespan prediction of glass fiber reinforced polymers subjected to flexural creep and elevated temperatures using analytical and numerical analyses
Authors: Alhayek Abdulrahman , Syamsir Agusril , Supian A. B. M. , Usman Fathoni
Published: August 2024

This paper presents the experimental, analytical, and numerical extensive investigation into the flexural creep performance of pultruded glass fiber reinforced polymer (pGFRP) composites at elevated service temperatures. The experimental phase involved a physical testing program on pGFRP coupons in a four‐point bending setup covering a wide range of loads (12%, 24%, and 37% stress levels) and temperature conditions (20, 40, and 60°C) over a long test duration of 720 h. The analytical Burgers model was employed to provide theoretical insights into the time‐dependent deformation behaviors, while the finite element analysis (FEA) simulations using derived reduction factor validated the accuracy of the proposed procedure. Burgers model was able to capture the experimental data very well and reached the ultimate strain failure limit within about 1.4–50 years depending on the case. The proposed simple FEA procedure yielded a pattern closely resembling the one observed from Burgers model in which they resulted in estimated endurance times with a roughly 15% difference between them.

Highlights

The higher stress and/or temperature, the longer the primary creep stage is.

Burgers model is able to capture the experimental data very well in all conditions.

Burgers general equation is able to predict failure within about 1.4–50 years.

A proposed reduction factor based on Burgers model is utilized in FEA

The FEA procedure shows a roughly 15% difference compared to Burgers model.
Studying the effect of different pore‐formers on characteristics and separation performance of PCTFE MF membrane
Authors: Yari Hamideh , Pakizeh Majid , Dashti Ali , Pourafshari Chenar Mahdi
Published: August 2024

When fabricating polymeric membranes using the non‐solvent induced phase separation (NIPS) technique, the characteristics and performance of the resulting membranes are significantly influenced by the additives incorporated into the casting solution. In this study, polychlorotrifluoroethylene (PCTFE) microfiltration (MF) membranes were fabricated using different pore‐formers including organic solvents, inorganic salts, and polymers. PCTFE was used as an attractive polymer for the first time in the liquid filtration process. This is due to its favorable properties for MF membranes such as ease of processing, high mechanical robustness, and fouling‐resistance. Dimethylformamide (DMF), ethanol, NaCl, ammonium bicarbonate, and polyethylene glycol (PEG) were incorporated at 1–4 wt% concentration as pore‐forming agents into the PCTFE solution. The prepared membranes were characterized by scanning electron microscopy (SEM), water contact angle measurement, and their filtration performance was assessed by pure water permeability (PWP) measurement and separation of milk fat in a cross‐flow membrane module. From the results, the overall porosity, surface porosity, mean pore size, hydrophilicity, PWP, steady flux, and fat rejection were in the following order for the modified membranes: PCTFE/DMF > PCTFE/PEG > PCTFE/ethanol > PCTFE/ammonium bicarbonate > PCTFE/NaCl. Among modified membranes, the highest fat rejection (95.8%) was obtained for the 1 wt% DMF‐containing casting solution. The fat rejection of this membrane was slightly less than the neat PCTFE membrane (97.5%), but its steady permeate flux was more than twice that of the pure sample. Additionally, the anti‐fouling and mechanical characteristics of the membranes were also investigated to assess the suitability of PCTFE polymers for the MF process.

Highlights

MF process was conducted using novel PCTFE flat‐sheet membranes.

The PCTFE membrane was prepared with different pore‐formers.

Using different concentrations of pore‐formers affected the membrane structure.

Using pore‐formers affected the PCTFE membrane performance.
Fabrication of antibacterial bio‐composite from polyvinyl alcohol incorporated with Azadirachta indica
Authors: Hossain Md. Tanvir , Shahid Md. Abdus
Published: August 2024

This study focuses on the development of a bio‐composite by combining polyvinyl alcohol (PVA) with Azadirachta indica (neem) extract using the film casting method. The morphological structure was analyzed using scanning electron microscopy (SEM), antibacterial properties were assessed through the agar disc diffusion method, and thermal behaviors were studied using TGA and DSC. Fourier transforms infrared spectroscopy (FTIR) was employed to investigate the bonding behavior, and a Universal Strength Tester was used to determine the mechanical properties. The SEM image revealed that the surface of the produced PVA and neem bio‐composite (PNBC) exhibited a moderate texture and porosity of 11.13% and 9.25%, respectively. The developed bio‐composite exhibited antibacterial activity with inhibition zones of 18 mm against E. coli and 21 mm against S. aureus. The FTIR spectra of the bio‐composites displayed distinctive peaks corresponding to both PVA and neem, confirming their presence in the material. The material's elongation at break (117.493 mm) and elongation at peak (64.159 mm) reflect its capacity for deformability and flexibility under stress. Moreover, PNBC has a Tg of 84°C, a pyrolysis temperature of 266°C, and degrades between 230 and 400°C, as shown by DSC and TGA. Finally, the results of this experiment were compared with available literature and a cost analysis was conducted.

Highlights

Bio‐composite is developed by combining PVA with Azadirachta indica (neem) extract using the film casting method.

The morphological structure, antibacterial properties, mechanical, and thermal behaviors have been studied.

The bio‐composite shows inhibition zones of 18 mm against E. coli and 21 mm against S. aureus.

The material's elongation at break (117.493 mm) and elongation at peak (64.159 mm) reflect its capacity for deformability and flexibility under stress.

The results are compared with the literature and a cost analysis is presented.
Experimental Study on Preparation and Physical Properties of Nanofluids
Authors: Liu Yan , Dong Mingda , Liu Zhihao , Gu Huichao
Published: August 2024

In this study, three nanofluids, CuO, SiC, and TiO2, are prepared by a two‐step method, and the factors affecting the stability, thermal conductivity, viscosity and density of the three are analyzed, so as to provide theoretical reference for strengthening heat transfer of the nanofluids. First, the effects of different dispersant addition amounts, magnetic stirring time, and ultrasonic oscillation time on the stability of nanofluids are analyzed in this paper, and finally chose the best solution for preparing three nanofluids. Second, the paper determines the thermal conductivity, viscosity, and density of three kinds of nanofluids and explores the factors affecting their physical properties. The thermal conductivity of the three nanofluids at the highest temperature is 2.9, 3.2, and 1.4 times that of the lowest temperature, respectively. When the temperature increased from 25 to 65 °C, the viscosity of CuO nanofluids decreases the most at different volume concentrations, and the viscosity decreases by 41.3% at 0.6% volume concentration. The density of nanofluids decreases with the increase of temperature and increases with the increase of volume concentration. At 25 °C, the density of SiC nanofluid increases the most with the volume concentration, and its density increases by 0.72%.
Risk factors and clinical outcomes of pulmonary hypertension associated with bronchopulmonary dysplasia in extremely premature infants: A systematic review and meta‐analysis
Authors: Li Bo , Qu Shuang‐Shuang , Li Ling‐Xue , Zhou Nan , Liu Ning , Wei Bing
Published: August 2024

This systematic review and meta‐analysis evaluated the risk factors for bronchopulmonary dysplasia associated pulmonary hypertension (BPD‐PH) in extremely premature infants (gestational age < 32 weeks) and its impact on outcomes. A computerized search of eight databases was performed, from the time of library construction to February 2024. The quality of the included studies was assessed with the Newcastle‒Ottawa scale. Statistical analyses were performed using RevMan 5.4.1 and Stata 16.0 software. Meta‐analysis of 2137 extremely premature infants revealed that oligohydramnios (OR = 2.21, 95% CI 1.06–4.61), low gestational age (SMD = −0.36, 95% CI −0.47 to −0.24), low birth weight (SMD = −0.54, 95% CI −0.74 to −0.35), small for gestational age (OR = 1.61, 95% CI 1.06–2.44), neonatal respiratory distress syndrome (OR = 2.05, 95% CI 1.45–2.91), grade III bronchopulmonary dysplasia (OR = 4.67, 95% CI 1.34–16.30), and sepsis (OR = 2.25, 95% CI 1.69–4.66) were risk factors for BPD‐PH, whereas antenatal steroids (OR = 0.66, 95% CI 0.49–0.88) were protective factors. BPD‐PH led to the extension of oxygen therapy (SMD = 0.67, 95% CI 0.42–0.92) and hospital stay (SMD = 0.77, 95% CI 0.14–1.40), and elevated the risk of discharged on oxygen (OR = 2.77, 95% CI 1.35–5.70) and death (OR = 4.38, 95% CI 2.21–8.69). BPD‐PH is a multifactorial disease. In this study, a total of seven risk factors, and one protective factor for BPD‐PH were identified in extremely premature infants. By managing and mitigating these factors, it is possible to decrease the occurrence of BPD‐PH. Furthermore, BPD‐PH may increase the risk of a poor prognosis in extremely premature infants.
Inhibition of Yeast Hexokinase by Acyl Glucosides of Phloretin and its Implication in the Warburg Effect
Authors: Cervantes Fadia V. , Fernandez‐Arrojo Lucía , Coscolin Cristina , Berrojo Alicia , Gonzalez‐Alfonso José L. , Perez de la Lastra José M. , Ferrer Manuel , Curieses‐Andres Celia M. , Andres‐Juan Celia , Ballesteros Antonio O. , Perez‐Lebeña Eduardo , Plou Francisco J.
Published: August 2024

Contrary to differentiated cells, cancer cells predominantly convert glucose to lactate even under conditions of adequate oxygen supply (“Warburg effect”). The initial enzyme implicated in this route is hexokinase, which transforms D‐glucose into D‐glucose‐6‐phosphate. We proposed the use of different polyphenols (resveratrol, epigallocatechin gallate, pterostilbene, phloretin) and their derivatives (α‐glucosides and acylated α‐glucosides) to inhibit this enzyme. For this study, we used Saccharomyces cerevisiae hexokinase, whose two isoforms show high resemblance at the active site with human hexokinase HK2. To monitor the reactions, a method of anion‐exchange chromatography coupled with pulsed amperometric detection (HPAEC‐PAD) was developed. Remarkably, most of the assayed compounds inhibited the enzyme more than 50 % in the standard assay. Among them, phloretin 4’‐O‐(6’’‐O‐octanoyl)‐α‐D‐glucopyranoside showed the highest inhibition and was studied in depth to determine the inhibition pattern and inhibition constant. The Ki for glucose was calculated to be 22.1±0.4 μM. Computational models of inhibition were carried out with the three molecules displaying the highest inhibition, and correlated adequately with the observed inhibitory effects on the enzyme. The inhibitory effect of several of the assayed polyphenols on hexokinase and their lack of toxicity renders them promising candidates as adjuvant drugs for cancer therapy.
Synthesis, Characterization, Antimicrobial and DFT Studies of Novel Quinolino‐Pyrazole Derivatives
Authors: Dayananda P. , Nayak Janardhana , Kudva Jyothi , Chethan D. M. , D'Souza Vineetha Telma
Published: August 2024

Synthesis of novel (E)‐N‐(4‐(substituted)benzylidene)‐6‐substituted‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carbothioamides/carboxamides was achieved by the condensation of 6‐substituted‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carbothioamides/carboxamides with substituted benzaldehydes in alcoholic medium in the presence of acetic acid. The structures of synthesized compounds are assigned on the basis of FT IR, 1H NMR, 13C NMR and Mass Spectral data. The compounds are subjected for their antibacterial, antifungal and DFT studies. Compounds, (E)‐6‐chloro‐N‐(4‐(dimethylamino)benzylidene)‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carbothioamide (5 b), (E)‐6‐chloro‐N‐(4‐(dimethylamino)benzylidene)‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carboxamide (5 f), and (E)‐6‐chloro‐N‐(4‐hydroxybenzylidene)‐1H‐pyrazolo[3,4‐b]quinoline‐1‐carboxamide (5 j) possessed pronounced antibacterial and antifungal activities due to their chemical structure.
A Photolithography‐Free Fabrication Strategy for Perovskite Photodetector Array with High‐Security Imaging Application
Authors: Zhang Jianfeng , Ding Ziyi , Liu Zhanwei , Li Guijun , Kwok Hoi‐Sing , Liu Yuan
Published: August 2024

Metal halide perovskites have attracted significant attention for high‐performance and cost‐effective photodetector (PD) arrays in recent years. Traditional perovskite photodetector arrays typically rely on planar structure and photolithography, which limit resolution and involve complex, costly processes. To address these challenges, an innovative, lithography‐free fabrication strategy is proposed utilizing direct laser writing ablation and a surface energy‐assisted selective growth process. A 10 × 10 self‐powered perovskite photodetector array is demonstrated with a vertical cross‐bar structure fabricated on a laser‐ablated textured Indium‐Tin Oxide (ITO) substrate which improves the device performance. The device exhibits a fast photoresponse and effective imaging capability. Moreover, the intrinsic physical disorder and randomness of perovskite provide highly secure entropy sources, making the photodetector array suitable for physical unclonable function (PUF) devices. This method offers a promising opportunity for simplifying the fabrication process, enhancing manufacturability, and advancing the application of perovskite PD arrays in secure imaging systems.
“I feel listened to and heard”: How social support fosters a sense of belonging for low‐income STEM majors
Authors: Payne Madison R. , LaDue Nicole D. , Dugas Daryl , Winitkun Duangkamon , Schmidt Stephanie
Published: August 2024

Persistence across undergraduate science, technology, engineering, and mathematics (STEM) programs is exceptionally low. Recent studies have shown that social support and sense of belonging are particularly important for students who are historically underrepresented in STEM, yet few interventions have directly targeted or investigated these factors. This qualitative study investigates low‐income, high‐achieving undergraduate STEM students' perceptions of their belonging in the context of a 2‐year peer social support group intervention. Interview analysis of 11 participants demonstrates that these STEM students attribute their sense of belonging to feelings or displays of comfort, commonality, community, and concerted effort. The peer group facilitated increases in participants' social support and sense of belonging by allowing participants to build friendships, recognize shared experiences, connect to their campus, build confidence with peers, and feel supported in their non‐academic and academic struggles. Although the program's main objective was to build participants' sense of belonging, the social support provided through the peer group also acted as a mechanism for increasing information‐related social capital. We recommend the implementation of similar non‐academic, supportive social spaces to increase the sense of belonging and overall persistence of low‐income STEM students.
Successful treatment of a case of feline idiopathic hypercalcaemia with cinacalcet
Authors: Peak Kerry , Paul Amanda , Walker Joshua , Rapastella Sofia , Jones Bryn , Diez Federico , Mellanby Richard
Published: August 2024

A 5‐year‐old, male, neutered, domestic shorthair cat was diagnosed with idiopathic hypercalcaemia. It had been previously treated for idiopathic sterile pyogranulomatous disease; however, at the time of diagnosis of the hypercalcaemia, it was receiving no treatment and there was no evidence of recurrence of disease. Treatment of the hypercalcaemia with alendronate, chia seeds and dietary modification was unsuccessful. Treatment with prednisolone was considered inappropriate due to the patient's pre‐diabetic state. Treatment was initiated with cinacalcet, which resulted in resolution of the hypercalcaemia. This report is the first to describe the successful use of cinacalcet to resolve hypercalcaemia in a cat.
Weather, heritage, and memory
Authors: Adamson George , Rapson Jessica
Published: August 2024

Sense of place and identity are related to the weather, and to memories and perceptions of what constitutes “normal” weather for a particular place. Weather is an important ingredient of cultural life; thus, long‐term changes to weather patterns can affect sense of place and sense of reality, although these changes will not be experienced uniformly. We argue that weather and climate should thus be considered forms of intangible cultural heritage, which we refer to as weather‐heritage. Drawing attention to place‐specific weather‐heritage that is threatened by climate change may increase support for mitigation and adaptation policies and encourage behavior change from individuals and governments. A heritage/memory lens can also draw attention to the ways in which lost weather‐heritage should be memorialized, ensuring that the right to memory of lost weather‐heritage is maintained. We therefore argue for a new research focus on weather‐heritage and memory, to understand how people remember and ascribe significance to particular weather types and patterns, and to document weather‐heritage that has been lost or is likely to be lost as climate changes. One purpose of this research should be to ensure that weather‐heritage is plural and does not become a majoritarian and exclusionary exercise in uncritical nostalgia.

This article is categorized under:

Climate, History, Society, Culture > Ideas and Knowledge

Perceptions, Behavior, and Communication of Climate Change > Perceptions of Climate Change

Trans‐disciplinary Perspectives > Humanities and the Creative Arts