bluuebunny/crossref_metadata_2025 huggingface dataset:
Health and economic effects on patients with type 2 diabetes mellitus in the long run: predictions for the Chilean population
Authors: Espinoza Manuel Antonio , Abbott Tomas , Passi Alvaro , Balmaceda Carlos
Published: October 2022

Background

Diabetes is associated to a high financial and disease burden, explaining a large proportion of expenditure of the health system in one year. The purpose of this study was to estimate long-term costs and health outcomes of recently diagnosed patients with type 2 diabetes in Chile.

Methods

Cost and consequence study based on mathematical discrete event simulation (DES) model. We modelled expected costs (USD) and quality-adjusted life-years (QALYs) from diagnosis to death (or the age of 95) of a hypothetical cohort of 100,000 incident cases, simulated based on the Chilean National Health Survey 2018. The incidence of twelve complications was estimated assuming the hazard functions provided by the United Kingdom Prospective Diabetes Study. We explore heterogeneity across patients based on their baseline risk covariates and their impact on costs and QALYs.

Results

The expected cost and QALY of a recently diagnosed type 2 diabetes patient in Chile were USD 8660 and 12.44 QALYs. Both costs and QALYs were independently determined by baseline risk and the patient's life expectancy from the diagnosis. Length of life since diagnosis showed the major impact on costs (5.2% increase for every additional year). Myocardial infarction was the most frequent complication (47.4%) and the most frequent cause of death.

Conclusion

Diabetes type 2 determines a significant expenditure of the health system and substantial health losses. Although the control of cardiovascular risk factors and the metabolic control of the disease, both have an important impact on costs and outcomes, the main impact is achieved by postponing the age of onset of the disease.
Are emojis ready to promote the WHO 5 moments for hand hygiene in healthcare?
Authors: Lotfinejad Nasim , Tartari Ermira , Sauser Julien , Fankhauser-Rodriguez Carolina , Pires Daniela , Pittet Didier
Published: October 2022

Background

Hand hygiene is universally recognized as a cornerstone measure for the prevention of healthcare-associated infections. Although the WHO “My five Moments for hand hygiene” poster has been used for more than a decade to delineate hand hygiene indications and promote action, adherence levels among healthcare workers are still notoriously low and disquieting. To compensate for the lack of effective hand hygiene communication, we aimed to evaluate emojis as possible surrogates for the non-verbal aspects of hand hygiene behaviour.

Methods

Following a thorough review of the Unicode version 12.0, the most applicable emojis to the terms used in the WHO 5 Moments poster were extracted. We developed a self-administered questionnaire to assess the view of infection prevention and control (IPC) practitioners regarding the use of emojis to show the WHO 5 Moments. Completed questionnaires were collected and analysed to determine the suitability of the existing emojis to illustrate a unified emoji poster. Data were analysed using R (version 3.6.3).

Results

A total of 95 IPC practitioners completed the questionnaire from May to October 2019 from different countries. Of these, 69 (74%) were female, and the mean age of the participants was 44.6 ± 10.87 years. We found appropriate emojis for six of the words used in the poster, including
"Image missing"
for touching (72%),
"Image missing"
for patient (63%),
"Image missing"
for clean (53%),
"Image missing"
for procedure (56%),
"Image missing"
for body fluid (58%), and
"Image missing"
for exposure risk (71%). The existing emojis proposed for the words “hygiene”, “aseptic”, and “surrounding” seemed to be less satisfactory.

Conclusions

In summary, the findings of this study indicate that the existing emojis may not be able to substitute the words used in the WHO 5 Moments poster. Emojis might be helpful to address hand hygiene indications in healthcare that may eventually play a role in promoting this measure. However, emojis should be further studied to choose the most appropriate ones and avoid ambiguity and misinterpretation. More emojis to convey health related messages are needed. We recommend further research in this area to evaluate the effect of using emojis in healthcare-related behaviours.
Powdered cellulose microblasting: a useful technique for dry-cleaning the reverse side of canvas paintings
Authors: Bautista-Morenilla Iris , Ruiz-Recasens Cristina , Iglesias-Campos Manuel Ángel , Oriola-Folch Marta
Published: October 2022

This study evaluates the effectiveness of microblasting with powdered cellulose for the dry-cleaning of canvases. Various surface cleaning tests were conducted by microblasting on the reverse of canvas paintings and the results were compared to those obtained with traditional dry-cleaning techniques using erasers and sponges. To assess cleaning effectiveness and potential changes on the support, the treated surfaces were examined both before and after cleaning using optical microscopy (OM), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM–EDX), confocal laser microscopy with surface roughness measurements, and spectrophotometry. The results from this comparative evaluation suggest that microblasting with powdered cellulose is a feasible technique for removing soiling on canvas and that it does not affect canvas structure or its topography. Furthermore, powdered cellulose leaves fewer particles of residues on the surface after cleaning, and these residues are chemically stable and compatible with the canvas support. Thus, the technique also avoids the potential negative long-term effects of eraser and sponge residues of particles that may remain on the canvas when these traditional systems are used.
Ultra-compact nonvolatile phase shifter based on electrically reprogrammable transparent phase change materials
Authors: Ríos Carlos , Du Qingyang , Zhang Yifei , Popescu Cosmin-Constantin , Shalaginov Mikhail Y. , Miller Paul , Roberts Christopher , Kang Myungkoo , Richardson Kathleen A. , Gu Tian , Vitale Steven A. , Hu Juejun
Published: October 2022

Optical phase shifters constitute the fundamental building blocks that enable programmable photonic integrated circuits (PICs)—the cornerstone of on-chip classical and quantum optical technologies [1, 2]. Thus far, carrier modulation and thermo-optical effect are the chosen phenomena for ultrafast and low-loss phase shifters, respectively; however, the state and information they carry are lost once the power is turned off—they are volatile. The volatility not only compromises energy efficiency due to their demand for constant power supply, but also precludes them from emerging applications such as in-memory computing. To circumvent this limitation, we introduce a phase shifting mechanism that exploits the nonvolatile refractive index modulation upon structural phase transition of Sb2Se3, a bi-state transparent phase change material (PCM). A zero-static power and electrically-driven phase shifter is realized on a CMOS-backend silicon-on-insulator platform, featuring record phase modulation up to 0.09 π/µm and a low insertion loss of 0.3 dB/π, which can be further improved upon streamlined design. Furthermore, we demonstrate phase and extinction ratio trimming of ring resonators and pioneer a one-step partial amorphization scheme to enhance speed and energy efficiency of PCM devices. A diverse cohort of programmable photonic devices is demonstrated based on the ultra-compact PCM phase shifter.
Decoupled wave equation and forward modeling of qP wave in VTI media with the new acoustic approximation
Authors: Liang Kai , Cao Danping , Sun Shangrao , Yin Xingyao
Published: October 2022

Acoustic approximation has received wide attention in modeling and inversion for the anisotropic wave equation to avoid high computational cost and parameter trade-off in seismic inversion. However, it also is limited by the stability condition, such as the instability for the qP-wave equation in transversely isotropic media with [Formula: see text]. We have developed a new approach that decoupled wave equation and forward modeling of the qP wave in vertical transversely isotropic (VTI) media with the new acoustic approximation. To keep dispersion relations ([Formula: see text]) of the qSV wave in each direction equal to zero, we formulate the vertical S-wave velocity ([Formula: see text]) to be a function of the model parameters and wavenumber component ([Formula: see text]), rather than setting it to zero. Then, the corresponding dispersion relation of pure qP for the new acoustic approximation is derived. According to this decoupled dispersion relation, we obtain the decoupled wave equation of pure qP wave in VTI media by inverse Fourier transform. To solve the wave equation in the space domain efficiently, the operator [Formula: see text] in the wave equation is characterized in the space domain by its asymptotic approximation operator [Formula: see text]. From the qP wave equation in the time-space domain, we realize the forward modeling of the pure qP wave in VTI media with the finite-difference method. The dispersion relation analysis and numerical examples find that the decoupled qP-wave equation with the new acoustic approximation does not contain the degenerate qSV wave and is a pure qP-wave equation, which is in good agreement with the simulation results of the elastic wave equation and has high accuracy and is stable in VTI media with [Formula: see text] or [Formula: see text].
The Acute Cytokine Response to 30-Minute Exercise Bouts Before and After 8-Week Endurance Training in Individuals With Obesity
Authors: Goj Thomas , Hoene Miriam , Fritsche Louise , Schneeweiss Patrick , Machann Jürgen , Petrera Agnese , Hauck Stefanie M , Fritsche Andreas , Birkenfeld Andreas L , Peter Andreas , Heni Martin , Niess Andreas M , Moller Anja , Weigert Cora
Published: October 2022

Context

One acute bout of exercise leads to a rapid increase in the systemic cytokine concentration. Regular exercise might alter the cytokine response, in particular in beforehand untrained and obese individuals.

Objective

Using a proximity extension assay, we studied the effects of acute exercise as well as endurance training on a panel of 92 cytokines related to inflammation.

Methods

A total of 22 individuals (30 ± 9 years; peak oxygen uptake [VO2peak] 25.2 ± 4.2 mL/[kg × min]; body mass index [BMI] 31.7 ± 4.4) participated in an 8-week endurance exercise intervention. Blood samples were collected before and immediately after 30 minutes’ ergometer exercise at 80% VO2peak.

Results

Before and after the training intervention, 40 and 37 cytokines, respectively, were acutely increased more than 1.2-fold (Benjamini-Hochberg [BH]-adjusted P < .05). The exercise intervention did not change the acute increase in cytokines nor the resting cytokine levels, whereas fitness was improved and adiposity reduced. The increase in fitness led to a slight increase in power output when exercising at the same heart rate, which might explain the comparable increase in cytokines before and after the intervention. The largest acute increase was found for OSM, TGFA, CXCL1 and 5, and TNFSF14 (≥ 1.9-fold, BH-adjusted P < .001). The transcript levels of these proteins in whole blood were also elevated, particularly in the trained state. Only the acute increase in IL6 (1.3-fold) was related to the increase in lactate, confirming the lactate-driven secretion of IL6.

Conclusion

Our comprehensive proteomics approach detected several underexplored serum exerkines with up to now less understood function in the adaptation to exercise.
The End of Economic Growth? Unintended Consequences of a Declining Population
Authors: Jones Charles I.
Published: October 2022

In many models, economic growth is driven by people discovering new ideas. These models typically assume either a constant or growing population. However, in high income countries today, fertility is already below its replacement rate: women are having fewer than two children on average. It is a distinct possibility that global population will decline rather than stabilize in the long run. In standard models, this has profound implications: rather than continued exponential growth, living standards stagnate for a population that vanishes. Moreover, even the optimal allocation can get trapped in this outcome if there are delays in implementing optimal policy. (JEL I12, J11, J13, O41)
The effect of part-time versus full-time spectacle use in myopia progression in children
Authors: Προύσαλη Ευθυμία
Published: October 2022

Σκοπός: Τα τελευταία χρόνια ο επιπολασμός της μυωπίας σημειώνει σημαντική αύξηση σε παγκόσμιο επίπεδο. Η διαδικασία της εμμετροποίησης πιστεύεται ότι καθοδηγείται από την υπερμετρωπική απο-εστίαση στο επίπεδο του αμφιβληστροειδούς χιτώνα, που συμβαίνει στην παρουσία ενός κοντινού στόχου. Το θολό είδωλο που δημιουργείται προκαλεί αυξημένη ανάγκη για προσαρμοστική λειτουργία, έτσι ώστε ο οφθαλμός να καταφέρει να εστιάσει το κοντινό είδωλο επάνω στον αμφιβληστροειδή χιτώνα. Η απο-εστίαση προερχόμενη από μειωμένη προσαρμοστική απάντηση έχει συσχετιστεί με την αναδιαμόρφωση του σκληρού χιτώνα και την αύξηση του αξονικού μήκους του οφθαλμού, τα οποία κατέχουν σημαντικό ρόλο στην ανάπτυξη μυωπίας. Σε αυτή τη βάση, η εφαρμογή πλήρους διόρθωσης θα μπορούσε να οδηγήσει σε αύξηση του ρυθμού εξέλιξης της μυωπίας. Στην παρούσα μελέτη, αξιολογήσαμε την επίδραση της μερικής διάρκειας διόρθωσης σε σύγκριση με την ολικής διάρκειας, πλήρη διόρθωση της μυωπίας, στην εξέλιξη της μυωπίας σε παιδιά σχολικής ηλικίας, Καυκάσιας καταγωγής. Μέθοδοι: Σε αυτήν την προοπτική ελεγχόμενη τυχαιοποιημένη κλινική μελέτη, συλλέχθηκαν δεδομένα από 30 παιδιά με αμφοτερόπλευρη μυωπία. Οι συμμετέχοντες τυχαιοποιήθηκαν στην ομάδα που έλαβε μερικής διάρκειας, πλήρη διόρθωση της μυωπίας (ομάδα παρέμβασης), ή στην ομάδα που έλαβε ολικής διάρκειας, πλήρη διόρθωση της μυωπίας (ομάδα ελέγχου), με μονοεστιακούς διορθωτικούς φακούς. Η αξιολόγηση της εξέλιξης της μυωπίας έγινε με τη μέτρηση της μεταβολής του κυκλοπληγικού σφαιρικού ισοδύναμου, του αξονικού μήκους, και του υπο-ωχρικού πάχους του χοριοειδούς χιτώνα, σε ένα διάστημα παρακολούθησης 12 μηνών. Αποτελέσματα: Συνολικά, 32 οφθαλμοί (16 ασθενείς) έλαβαν μερικής διάρκειας, πλήρη διόρθωση της μυωπία (ομάδα παρέμβασης), και 28 οφθαλμοί (14 ασθενείς) έλαβαν ολικής διάρκειας, πλήρη διόρθωση της μυωπίας (ομάδα ελέγχου). Δεν παρατηρήθηκε σημαντική διαφορά ανάμεσα στις ομάδες μερικής και ολικής διάρκειας διόρθωσης της μυωπίας στη μέση μεταβολή στο σφαιρικό ισοδύναμο, στο αξονικό μήκος, και στο υπο-ωχρικό πάχος του χοριοειδούς χιτώνα, κατά τη 12μηνη παρακολούθηση. Η ομάδα που έλαβε μερικής διάρκειας διόρθωση απείχε από τη χρήση διορθωτικών φακών κατά τις δραστηριότητες σε κοντινή απόσταση, για ένα μέσο χρονικό διάστημα 6.2 ωρών σε καθημερινή βάση. Οι ομάδες παρέμβασης και ελέγχου παρουσίασαν παρόμοια μέση μεταβολή στο σφαιρικό ισοδύναμο (MD: -0.05 D, 95% CI: -0.50 - 0.39 D; P 0.81), στο αξονικό μήκος (MD: -0.07 mm; 95% CI: -0.20 - 0.06 mm; P 0.30), και στο υπο-ωχρικό πάχος χοριοειδούς χιτώνα (MD: -11.45 μm; 95% CI -22.60 – 14.16 μm; P 0.67). Συμπεράσματα: Προτείνουμε ότι η μερικής διάρκειας διόρθωση της μυωπίας δεν παρουσίασε σημαντική διαφορά στον έλεγχο της εξέλιξης μυωπίας, συγκρινόμενη με την ολικής διάρκειας διόρθωση της μυωπίας, σε παιδιά Καυκάσιας καταγωγής που έλαβαν πλήρη διόρθωση με μονο-εστιακούς φακούς για ένα χρονικό διάστημα 12 μηνών.
Σύνθεση, χαρακτηρισμός και μελέτη ιδιοτήτων νέων Μέταλλο-Οργανικών Κατασκευών
Authors: Πλέσσας Αλέξιος
Published: October 2022

Στην παρούσα διδακτορική διατριβή, μελετάται η χημεία ένταξης δισαμιδικών υποκαταστατών, που αποτελούν παράγωγα του διχλωριδίου είτε του οξαλικού είτε του τερεφθαλικού οξέος με 4 ή 5-άμινοσαλυκιλικό οξύ ή και τερεφθαλικό οξύ. Με τους υποκαταστάτες αυτούς απομονώθηκαν 10 IR-MOF-74 από τα οποία τα 6 αποτελούν νέα προϊόντα ενώ τα υπόλοιπα 4 ήταν γνωστά από τη βιβλιογραφία. Επιπλέον συντέθηκαν και 6 νέα προϊόντα που αποτελούν παραμορφωμένα ανάλογα της οικογένειας των IR-MOF-74. Τα παραπάνω υλικά μελετήθηκαν ως προς τη ρόφηση γλυκόζης αλλά και ως τροποποιητές ηλεκτροδίου πάστας άνθρακα για τον μη ενζυματικό ηλεκτροχημικό προσδιορισμό της γλυκόζης στον ανθρώπινο ιδρώτα. Για τον ίδιο σκοπό συντέθηκαν και μελετήθηκαν και 3 σύμπλοκα του Cu(II) με πολλά υποσχόμενα αποτελέσματα (Πίνακας 14) που οδήγησαν και σε δημοσίευση, ενώ οι αντίστοιχες μελέτες με τα MOFs βρίσκονται ακόμα υπό επεξεργασία.Παράλληλα οι ίδιοι υποκαταστάτες χρησιμοποιήθηκαν και με μέταλλα της λανθανιδικής σειράς, οδηγώντας στην απομόνωση 4 νέων πολυμερών ένταξης, τα οποία χαρακτηρίστηκαν πλήρως με κρυσταλλογραφία ακτίνων Χ επί μονοκρυστάλλου, και των οποίων οι ιδιότητες και πιθανές εφαρμογές βρίσκονται ακόμα υπό μελέτη.Τέλος συνεχίστηκε η μελέτη της οξικής σαλικυλαλδοξίμης, η οποία είχε ξεκινήσει κατά τη διάρκεια των σπουδών μου για την απόκτηση του μεταπτυχιακού διπλώματος ειδίκευσης, με ιόντα της 3d σειράς, οδηγώντας στην απομόνωση 2 νέων προϊόντων, τα οποία χαρακτηρίστηκαν πλήρως με κρυσταλλογραφία ακτίνων Χ επί μονοκρυστάλλου. Το πρώτο αποτελεί πολυμερές ένταξης δύο διαστάσεων (που εκτείνεται στην τρίτη μέσω δεσμών Η) και έχει μελετηθεί για τις μαγνητικές του ιδιότητες, ενώ το δεύτερο απομονώθηκε πολύ πρόσφατα και οι ιδιότητές του είναι ακόμα υπό μελέτη.
Ο καθορισμός του καθεστώτος πρόσφυγα υπό το πρίσμα του διεθνούς και του ενωσιακού δικαίου.
Authors: Κουτσοπούλου Αικατερίνη
Published: October 2022

Η παρούσα διδακτορική διατριβή μελετά τα κριτήρια για την υπαγωγή των αιτούμενων διεθνούς προστασίας στο καθεστώς του πρόσφυγα και ειδικότερα τις ρήτρες υπαγωγής και τις ρήτρες αποκλεισμού από την εν λόγω διεθνή προστασία. Οι ρήτρες υπαγωγής καθορίζουν τις προϋποθέσεις που πρέπει να συγκεντρώνει ένα πρόσωπο, προκειμένου να χαρακτηριστεί πρόσφυγας και συνιστούν τη θετική βάση για την αναγνώριση του καθεστώτος πρόσφυγα. Οι ρήτρες αποκλεισμού έχουν αρνητική σημασία καθώς περιλαμβάνουν τις περιπτώσεις υπό τις οποίες ένα πρόσωπο, παρά του ότι ανταποκρίνεται στα θετικά κριτήρια που προβλέπουν οι ρήτρες υπαγωγής, εντέλει αποκλείεται από το καθεστώς του πρόσφυγα. Η μελέτη των ανωτέρω ρητρών εκκινεί από τη Σύμβαση για το Καθεστώς των προσφύγων του 1951, η οποία αποτελεί το ισχύον διεθνές νομοθετικό πλαίσιο και στη συνέχεια εκτείνεται στον ενωσιακό δίκαιο και ειδικότερα στην Οδηγία 2011/95/ΕΕ σχετικά με τις απαιτήσεις για την αναγνώριση των υπηκόων τρίτων χωρών ή των απάτριδων ως δικαιούχων διεθνούς προστασίας, για ένα ενιαίο καθεστώς για τους πρόσφυγες ή για τα άτομα που δικαιούνται επικουρική προστασία και για το περιεχόμενο της παρεχόμενης προστασίας.
The impact of Covid-19 pandemic on hospices: A systematic integrated review and synthesis of recommendations for policy and practice
Authors: van Langen-Datta Shalene , Wesson Helen , Fleming Joanna , Eccles Abi , Grimley Catherine , Dale Jeremy , Almack Kathryn , Mayland Catriona , Mitchell Sarah , Driscoll Ruth , Tatnell Lynn , Roberts Lesley , MacArtney John I.
Published: October 2022

Background: The Covid-19 pandemic resulted in the development of numerous recommendations for practice and policy for specialist palliative care provided by hospices in United Kingdom (UK), as hospices were significantly affected by the pandemic and protections put in place. The aim of this review is to identify and synthesise recommendations or implications for policy and practice that have been generated for adult hospice specialist palliative care during the first 24 months of the Covid-19 pandemic. Methods: AMED, BNI, CINAHL, EMBASE, EMCARE, HMIC, Medline, PsycINFO, PubMed databases were searched for peer-reviewed papers, as well as hand searchers for grey literature. Literature relating to hospices and Covid-19 in the UK were included and a thematic synthesis of recommendations for hospice policy and practice was undertaken. Results: 858 articles were identified with 12 meeting the inclusion criteria. Fifty-eight recommendations or implications were identified: 31 for policy, 27 for practice, and 10 covering both. Recommendations were organised under ten themes. There were several recommendations seeking to secure hospice resources to mitigate the short-term impact of the pandemic, as well as those focused on longer-term implications such as core funding. The impact of the pandemic on the quality of hospice care was the focus for numerous recommendations around improving integration of hospice care in the community, provision of bereavement support and better use of Advance Care Plans (ACP). However, there were significant gaps related to carer visitation in hospices, inequities of palliative care, or hospice-at-home services. Conclusion: The Covid-19 pandemic and protections exposed several ongoing policy and practice needs, especially around hospice resources, while generating novel issues for hospices to address. Significant policy gaps remain to be addressed to mitigate the impact of the pandemic on the quality of hospice specialist palliative care.
Galileusz i rozróżnienie między jakościami pierwotnymi a wtórnymi (I). Argument superesencjalistyczny
Authors: Żukowski Bartosz
Published: October 2022

Wprowadzone w Wadze probierczej rozróżnienie między jakościami pierwotnymi i wtórnymi było dotychczas analizowane niemal wyłącznie z historycznej perspektywy. Niniejszy artykuł, pierwszy z dwóch planowanych, ma na celu nadrobienie tych zaległości poprzez systematyczną, teoretyczną analizę głównego argumentu użytego przez Galileusza do sformułowania tej dystynkcji. W pracy zrekonstruowano główne kroki tego argumentu, a także zidentyfikowano i omówiono leżące u jego podstaw presupozycje epistemologiczne i ontologiczne, z których najistotniejsza i najbardziej oryginalna okazała się zasada superesencjalistyczna, implikująca współzależność między istotnością i realnością własności ciała materialnego. Precyzyjna rekonstrukcja założeń tkwiących u podstaw rozumowania Galileusza przygotowuje grunt pod analizę najbardziej kontrowersyjnego aspektu jego koncepcji – kwestii ontologicznego statusu jakości wtórnych. Zagadnienie to zostanie podjęte w następnym artykule.
Edward Dembowski (1822-1846) – krytyk filozofii eklektycznej
Authors: Roskal Zenon
Published: October 2022

W artykule przedstawiam koncepcję eklektyzmu wypracowaną przez Edwarda Dembowskiego na tle współczesnych jego koncepcji i typologizacji. Interpretuję eklektyzm Dembowskiego jako achroniczną, trójpostaciową postawę filozoficzną, która staje się pojęciowym narzędziem dającym się wykorzystać w historii filozofii do charakterystyki dokonań filozofów w różnych epokach, ale także do uwypuklenia i bardziej precyzyjnego ujęcia tego, co w filozofii jest oryginalne i nowe.
Sprzeciw sumienia w zawodzie farmaceuty. Badanie opinii farmaceutów na temat klauzuli sumienia
Authors: Czekajewska Justyna , Langer Dominik , Baum Ewa
Published: October 2022

Streszczenie  

Klauzula sumienia została wprowadzona do obszaru prawnych regulacji międzynarodowych w związku z uchwałą Rady Europy o nr 1763 z dnia 7 października 2010 r. Zgodnie z treścią dokumentu istnieje przyzwolenie odstąpienia od wykonania określonego świadczenia medycznego ze względu na zastrzeżenia moralne (religijne lub światopoglądowe) zgłaszane przez przedstawicieli opieki zdrowotnej.

 W przepisach polskiego prawa medycznego powołanie się na zasadę klauzuli sumienia jest dozwolone, ale wyłącznie dla lekarzy, pielęgniarek i położnych. Farmaceuci są pozbawieni tej możliwości. Jednak wykonywanie niektórych czynności zawodowych budzi zastrzeżenia etyczne wśród farmaceutów. Autorzy artykułu postanowili zbadać opinię farmaceutów zarówno na temat klauzuli sumienia oraz określonych regulacji prawnych, które zdaniem respondentów powinny podlegać zmianom legislacyjnym.

 Celem pracy jest zaprezentowanie wyników z przeprowadzonych badań, które zostały zrealizowane w 2020 r. na terenie Wielkopolskiej Okręgowej Izby Farmaceutycznej w Poznaniu.

 

Słowa kluczowe: wolność sumienia i wyznania, klauzula sumienia, farmacja, antykoncepcja, Polska
Przyroda w siedemnastowiecznym laboratorium (Radosław Kazibut, Filozofia przyrody i przyrodoznawstwa Roberta Boyle’a (Poznań: Wydawnictwo Naukowe UAM, 2019), ss. 205)
Authors: Grzeliński Adam
Published: October 2022

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SIMULATION OF DEBULKING IN RESIN-SATURATED COMPOSITE PREPREGS USING A PORE-PRESSURE COHESIVE ZONE MODEL
Authors: SEON GUILLAUME , NIKISHKOV YURI , MAKEEV ANDREW , SHONKWILER BRIAN
Published: October 2022

Aircraft composite parts are commonly manufactured from resin-saturated thermoset pre-impregnated plies laid-up over a rigid tool and consolidated and cured in an autoclave. In many applications, autoclave consolidation alone is not sufficient to remove the air, or bulk, that has been entrapped within the laminate during layup and may lead to the formation of voids in the final part. Entrapped air at ply interface can also participate in the formation of ply wrinkles, especially in curved laminates. High bulk content in curved sections is associated with an excess of ply length material that builds up during the layup. During compaction, this excess ply length may be squeezed into a tighter radius, which might lead to ply buckling and formation of wrinkles. Wrinkles and voids may significantly affect structural integrity of composite structures and increase rejection rates in the production cycle. Debulking, or vacuum consolidation, has been a common practice extensively used by aircraft manufacturers to reduce the amount of air entrapped during the layup of composite parts prior to curing. Yet, the underlying physical principles governing formation of defects during debulking are not well understood. This work is part of the Office of Naval Research (ONR) project “Physics-Based Composite Process Simulation” that seeks to fill the gaps in understanding the physical principles governing the formation and evolution of manufacturing defects. Recently, the authors of this work have introduced an approach for modeling debulking in resinsaturated prepregs where cohesive elements enriched with pore-pressure degree of freedom are inserted at ply interfaces, using simulation concepts originally developed for the analysis of hydraulic fracturing in geomechanics problems. Further improvement of the methodology combined the pore-pressure cohesive zone model with cohesive contact to capture the tacky behavior of the interface. This work presents a verification of the ability of the method to capture the physics involved during debulking at the coupon scale using a two-ply carbon/epoxy IM7/8552 debulk test specimen with a seeded wrinkle. The methodology is then further extended and verified at the element scale for the first time for simulation of debulking in a rotor blade grip test element.
MOISTURE INFLUENCE ON VISCOELASTIC AND THERMAL PROPERTIES OF ADDITIVELY MANUFACTURED SYNTACTIC FOAMS
Authors: SUBRAMANIYAN SABARINATHAN P. , PRABHAKAR PAVANA
Published: October 2022

Syntactic foams are lightweight structures extensively used in marine and aerospace applications as core materials due to their inherent buoyant nature and energy absorption capability. In addition to structural applications, syntactic foams find applications in microelectronics. However, exposure to moisture for a prolonged period will mediate moisture ingression into syntactic foams that will eventually degrade the structure and cause catastrophic failure. Despite its importance, most of the past research has focused primarily on experimental studies of mechanical property degradation of syntactic foams. In contrast, time-dependent property degradation due to moisture exposure is lacking. Such behavior of additively manufactured syntactic foams is not known. To address this knowledge gap, this paper focuses on elucidating the impact of moisture absorption on the viscoelastic and thermal properties of syntactic foams, particularly Thermoplastic Polyurethane (TPU) based syntactic foams. In this paper TPU based syntactic foams with 20% and 40% reinforced glass micro balloons (GMBs) are additively manufactured using selective laser sintering. To that end, the viscoelastic and thermal properties are measured in both pristine and water-aged syntactic foams. Dynamic mechanical analysis is performed at temperatures from -50 oC to 100 oC at 0.1% strain and 1 Hz. It was found that glass transition temperature increases with an increase in GMB volume fraction due to the effect of reinforcement, which hinders the polymer chain movement at the interface. The peak damping factor, which is representative of ???, is reduced by 5% in neat TPU and TPU + 20% GMB after the exposure due to plasticizing effect in TPU whereas no change is found in TPU+40% GMB foams. This is attributed to the majority of the moisture absorption occurring at the interface between GMB and matrix. The thermal conductivity of the neat TPU and TPU+20% GMB is increased by 8% after the samples are exposed to moisture due to the formation of thermal bridges when water molecule reacts with TPU matrix, however, it slightly decreased in TPU+40% GMB due to insufficient formation of thermal bridges as a result of insufficient matrix and hindrance from the reinforcement. Our results demonstrate that the thermal properties of the syntactic foams can be tailored based on our knowledge of their response to moisture and exposure time.
EFFICACY OF CELLULOSE FIBER AS BACTERIA CARRIER FOR SELF-HEALING CONCRETE AND 3D POLYMER MICROSTRUCTURE
Authors: IGBOKWE EMMANUEL , IBEKWE SAMUEL , MENSAH PATRICK , AGU OGAD , ABEDIN RUBAIYAT
Published: October 2022

Microcracks are known to occur at an early stage in constructions utilizing concrete thereby affecting its serviceability and increasing the cost of repair and maintenance. As a result, there is a growing need to use a microbiological crack-healing strategy to arrest and mitigate the impact of the microcracks. The microbial system's distinguishing characteristic is that it allows concrete to self-heal. This study addresses the efficiency of microbiologically induced calcite precipitation in increasing the durability and selfhealing of cementitious construction materials. The primary focus has been on developing a carrier to protect the bacteria from being crushed during casting and from the harsh environment. The results of the SEM examination demonstrated that cellulose fiber bacteria can live at temperatures as high as 160 degrees Celsius, as opposed to direct bacteria, which can only survive at temperatures as high as 60 degrees Celsius. On the 28th day of curing, the cellulose fiber bacteria exhibited a 25% improvement in split tensile and compressive strength over the control concrete. Furthermore, after 28 days, the Cellulose fiber bacteria self-healed up to 1.5 mm fracture concretes via wetdry technique and 2.5 mm crack concretes by induced method after 40 days. Fiber-Sphaericus bacteria capable of producing spores and 3D printed materials to grow bionic mineralized composites with ordered microstructure was utilized. Bionic composites outperformed the control microstructure by 50% in terms of specific compressive strength and fracture toughness, and they also self-healed a larger percentage of the lattice beam within 12 days. This study contributes towards the development of 3D-architectural hybrid synthetic living materials with live ordered microstructures.
DIELECTRIC ANALYSIS TO PREDICT MOISTURE ABSORPTION IN STRUCTURAL COMPOSITES: A DATA-DRIVEN APPROACH
Authors: DAS PARTHA PRATIM , RABBY MONJUR MORSHED , VADLAMUDI VAMSEE , RAIHAN RASSEL
Published: October 2022

Due to continual exposure to moist environment, environmental degradation is a major threat to structural composites throughout their service life. Impedance Spectroscopy (IS)/Broadband Dielectric Spectroscopy (BbDS) is a reliable nondestructive method that has been used in polymer industries for dielectric characterization of material. While moisture absorption causes irreversible changes in the polymer matrix composites, it also alters the electrical properties of the system which is detectable using BbDS. Since the physics that drives the change in electrical characteristics is driven by the modifications imposed by water molecules (whether free or bound), both events can be linked. A dielectric spectrum over a broad frequency range can give an accurate estimation of moisture absorption in structural composites. In this work, machine learning (ML) models (Discriminant Analysis (DA) and Support Vector Machine (SVM) with Principal Component Analysis (PCA)) were developed that incorporate the dielectric data from BbDS to predict the current material state due to hygrothermal ageing. The models not only can detect the presence of moisture in composites, but also can predict the current saturation state of the material based on their dielectric properties. It uses the dielectric spectra and composite’s geometry as features to train supervised learning classification algorithms. The ML models developed in this study shows high accuracy and efficiency in predicting the current moisture state of the composite test samples due to hygrothermal ageing.
BUILDING AND BREAKING CARBON COMPOSITES WITH REACTER
Authors: GISSINGER JACOB R. , WISE KRISTOPHER E.
Published: October 2022

Carbon-based composites have become indispensable materials in aerospace and other high-performance applications, yet obtaining a detailed, nanoscale understanding of their morphology and failure mechanisms using only experimental methods remains a difficult challenge. REACTER is a versatile computational modeling tool for atomistic molecular dynamics simulations designed to model chemical reactions at the speed and length scales of classical force fields. In this work, several recent features of REACTER were applied to the creation and subsequent mechanical testing of two classes of carbon composites: carbon nanotube (CNT) composites and carbon fiber reinforced polymers (CFRP). A network of CNTs was grown dynamically using the new ‘create atoms’ feature of REACTER. The CNT filler was embedded into a polyarylacetylene (PAA) matrix by simulated in situ polymerization to obtain the final composite model. To generate the second class of carbon composite, fully carbonized (graphitic) carbon fiber morphologies were created by the method of Desai et al. [1], but using the advanced reaction constraints framework of REACTER. Two fiber models were created, representing a circular carbon fiber core and a flat surface, and similarly infiltrated with resin to obtain the final CFRP structure. Failure mechanisms were elucidated by simulating mechanically induced bond breaking, as characterized by third order DFT-based tight-binding simulations, via a reaction constraint on the total potential energy of the involved atoms.
INVESTIGATION OF MECHANICAL PROPERTIES OF COMPOSITES-BASED SHEET LAMINATION ADDITIVE MANUFACTURING PROCESS
Authors: YOUNG DEVIN , VONDRASEK BRITANNIA , CZABAJ MICHAEL
Published: October 2022

The Composites-Based Additive Manufacturing (CBAM) system is a novel sheet lamination process combining mats of randomly oriented carbon fiber (CF) reinforcement with thermoplastic matrix materials to fabricate composite objects. This study investigated the suitability of three ASTM test standards for tensile, inplane shear, and interlaminar fracture properties of two CBAM material systems: CF reinforced Nylon-12 (CF/PA12) and CF reinforced polyether ether ketone (CF/PEEK). The tensile, in-plane shear, and interlaminar fracture tests were well suited for the CF/PEEK material, though high variability was found in the interlaminar fracture response. The CF/PA12 material system exhibited high plasticity and evidence of a poor fiber-matrix interface. This was shown by fiber pullout in the tensile tests and the presence of voids observed on the in-plane shear surfaces. The interlaminar fracture test method was invalid for the CF/PA12 material due to a large process zone invalidating. These results show CF/PEEK to be a promising material system for the CBAM process while CF/PA12 requires further development.
RESPONSE OF MICROVASCULAR COMPOSITES TO IN-PLANE SHEAR LOADING
Authors: BARNETT PHILIP , FURMANSK JEVAN , BAUR JEFFREY , BUTCHER DENNIS
Published: October 2022

Microvascular composites were manufactured with precise channel spacing aligned to and transverse to the fiber direction using a custom tool. Stainless-steel tubes and sacrificial polylactic acid were used to produce microchannels following the standard curing schedule with modification to the post-cure step. Optical and radiographic evaluation showed that the microchannels were well-aligned. Transverse microchannels yielded large resin “eyes” and voids near the channels, as well as deformed the sacrificial PLA filament, while microchannels aligned to the fibers yielded undisturbed microstructures with circular cross-section channels. In-plane shear testing revealed that transverse microchannels cause a disturbance in the stress state of the composites when subjected to shear loading. Channels aligned to the fibers failed at the microchannels, though their penalty to the shear properties was small. This study shows that the shear properties of microvascular composites are comparable to those of neat composites, allowing for the addition of multifunctionality with little penalty.
NUMERICAL INVESTIGATION OF SHAPE-MEMORY ZIRCONIA-REINFORCED METAL-MATRIX COMPOSITE FOR ENERGY DISSIPATION AND HIGH TEMPERATURE APPLICATIONS
Authors: YACOUTI MARWA , SHAKIBA MARYAM
Published: October 2022

This paper aims to exploit the shape-memory behavior of zirconia in order to design a composite with enhanced strength, energy dissipation, and strain recovery upon heating. Zirconia is characterized by two properties: superelasticity and the shapememory effect. These unique features are achieved through the reversible phase transformation from a high-temperature tetragonal phase to a low-temperature monoclinic phase. This study examines the response of shape-memory zirconia-reinforced aluminum-matrix composite under mechanical and thermal loadings. Microstructural finite element simulations are conducted to investigate the impact of the yield stress of the matrix, as well as the volume fraction and the diameter of zirconia particles on the response of the composite. The results of this study show that shape-memory zirconia reinforcing particles contributed effectively to the strength enhancement. In fact, it is found that 50% zirconia volume fraction can improve the maximum stress and the energy dissipation by 76% and 38%, respectively, at 4% tensile strain. Furthermore, 23% recoverable strain can be achieved upon heating up to 700◦K. This work provides insights into the potential application of shape-memory zirconia as reinforcing particles for damping systems and high temperature actuation.
MICRO SCALE AND BULK-LEVEL (POLYCRYSTALLINE) SIMULATIONS OF BORON CARBIDE FOR CERAMIC MATRIX COMPOSITE APPLICATIONS
Authors: ALUKO OLANREWAJU
Published: October 2022

This study applied computational molecular dynamics (MD) to model crystalline boron carbide (B4C) using the Large-scale Atomic/Molecular Parallel Simulator software package. The Reax Potential Force Field was utilized at a strain rate of 107/s to evaluate micro-scaled mechanical behaviors of the material system. Then, the bulk– level (polycrystalline) behavior was evaluated using the relation between single crystal elasticity and the effective elastic behavior of polycrystalline materials. The simulations and analysis provide the link between the microscale and bulk-level performances of boron carbide, and the results at both length scales agree with the experimental data in the literature. The computational method can also be used to further develop strong and light-weight materials for aerospace, automotive, and military applications at relatively low costs of high-performance computational tools and higher throughput.
EFFECTS OF GRAPHENE ON TWISTING OF HIGH DENSITY POLYETHYLENE
Authors: ANILAL ASHISH , BENDESKY JUSTIN , JEONG SEHEE , LEE STEPHANIE S. , BOZLAR MICHAEL
Published: October 2022

High density polyethylene (HDPE) is known to form banded spherulites when crystallized from the melt. In such spherulites, concentric bands of alternating light and dark colors emanating from the spherulite nucleation center are observable between cross polarizers and appear as a function of the anisotropy of the dielectric susceptibility as crystal orientations continuously rotate about the growth direction. Recently, we identified PE to be a promising compound to induce twisting in conjugated carbonaceous systems, such as triisopropylsilylethynyl anthradithiophene (TIPS ADT). When blended together in ratios between 10 – 70 wt.% PE, TIPS ADT and PE crystals twist in concert with one another to form composite films of intertwined helicoidal fibrils. In this work, we investigate crystal twisting in HDPE-graphene oxide composites. In addition to its unique multifunctionality, graphene has also recently demonstrated peculiar twisting capabilities that strongly alter its physical properties. Here, we first produce graphene sheets through the chemical oxidation of natural graphite, and then investigate the influence of graphene on the twisting of HDPE composites under various processing parameters (graphene concentration, polymer cooling rate, etc). HDPE-graphene composites have been prepared using melt extrusion in the form of microfibers and films. We measured the influence of twisting on the mechanical and electrical properties of the composites, as well as the crystallographic structure using optical and electron microscopy, and X-Ray diffraction spectroscopy.
COUPLED STRUCTURAL THERMAL ANALYSIS OF THE DEFECT FORMATION PROCESS DURING CFRP TAPE LAYUP
Authors: MIZUTA TOGO , NISHIKAWA MASAAKI , NISHI MASATO , MATSUDA NAOKI , HOJO MASAKI
Published: October 2022

The Automated Fiber Placement (AFP) is the technology for automated layup of multiple narrow prepreg tapes in CFRP (Carbon Fiber Reinforced Plastics) manufacturing of structural components for aircraft. Because most AFP devices cut the material perpendicular to the feed direction, geometrically complex layup can result in localized gaps and overlaps that can affect the mechanical properties of the molded product. The bending modulus of prepreg tapes is the dominant factor for defect formation in the layup process. For the layup using CFRTP (Carbon Fiber Reinforced Thermoplastics) tapes, the material is heated during the tape layup and thus the temperature variation and distribution during forming have a large effect on the bending modulus of prepreg tapes [1]. In this study, we modeled the laminate with internal defects made by the AFP process, and we performed a coupled structural thermal analysis for the gap elimination when the out-of-plane pressure was applied, considering the temperature-dependent material properties of CFRTP. We showed a relationship between the bending stiffness of the layer above the gap and defect formation in CFRTP.
HIGH-SPEED NANOSCALE TO MACROSCALE COMPOSITE PREDICTION TOOL USING NEURAL NETWORKS
Authors: HANKINS SARAH N. , JANA ASMITA , FERRALIS NICOLA , FERTIG, III RAY S.
Published: October 2022

Material properties of carbon fiber composites were linked from the nanoscale to the macroscale via molecular dynamics simulations and finite element analysis. In particular, the study focused on predicting the properties of PAN-based and pitchbased carbon fiber composite specimen. The atomistic features that develop throughout the manufacturing process were captured within the molecular dynamics simulations, while the microstructural features and composite layup information were captured within the finite element analysis model. However, in order to obtain the desired material property values, a significant amount of modeling experience is required. Therefore, the purpose of this research was to remove the finite element analysis models by training sets of neural networks to quickly and accurately predict properties from the nanoscale to the macroscale. When compared to experimental data, the errors of the high-speed composite prediction tool were all less than 10%. Ultimately, this tool can provide a rapid analysis of different fiber manufacturing techniques and composite layups to provide insight and understanding on how to better tailor the properties of carbon fiber composites for various applications.
DESIGN OF COMPOSITES FOR ADDITIVE MANUFACTURING: TAILORING OF INDIVIDUAL LAMINA
Authors: MAC GARY , YANAMANDRA KAUSHIK , GUPTA NIKHIL
Published: October 2022

The research and development of polymer composite materials for additive manufacturing (AM) is critical for potential applications in the aerospace, automotive, and construction industries. The properties of the additive manufactured composite component are highly dependent on factors such as slicing thickness, infill pattern, infill direction, infill density, and fiber volume fraction. An additive manufactured composite part fabricated with different infill directions can have the same density but an immense effect on the resulting mechanical response of the components. This study is focused on exploring the possibility of developing composite material parts with different material layering pattern within each lamina to obtain highly tailored mechanical properties that cannot be obtained in traditional laminated composites. The results show that additive manufacturing provides a versatile method for developing composites that cannot be developed by the traditional methods by tailoring the properties of individual lamina in multiple directions.
TRANSVERSE TENSILE STRENGTH PREDICTION OF THERMOSETTING COMPOSITES
Authors: SHAH SAGAR P. , MAIARU MARIANNA
Published: October 2022

The transverse tensile strength of composites is susceptible to size effects. Therefore, it is paramount to develop length-scale specific physical test procedures to validate computational models that estimate the transverse composite response using micromechanics. To this end, a computational process modeling and virtual mechanical testing framework are presented in this study to predict the transverse response of composite microstructures subjected to processing conditions. Informed by a comprehensive material dataset, the numerical model is shown to reliably predict the process-induced residual stress generation in composite microstructures and accurately evaluate its influence on their transverse strength prediction. A novel procedure to fabricate thin composite laminates from a single ply of carbon fibers and characterize their transverse tensile response is presented to validate the numerical model. The results show excellent agreement with the virtual test predictions. This study highlights the importance of length-scale specific testing to minimize the influence of size effect on the transverse composite strength.