bluuebunny/crossref_metadata_2025 huggingface dataset:
Construction of a hollow MOF with high sedimentation performance and co-immobilization of multiple-enzymes for preparing rare ginsenoside CK
Authors: Cao Shanshan , Li Runze , Tian Fei , Liu Xiaochen , Fan Daidi , Wu Zhansheng
Published: July 2023

1. Sna&β-G@H-Cu-BDC biocomposite was synthesized via the hydrogel-template method with larger size. 2. Sna and β-G were co-immobilized in the hollow Cu-BDC MOF to produce the rare ginsenoside CK with cascade catalysis. 3. The Sna&β-G@H-Cu-BDC biocomposite has good sedimentation performance.
Catalytic heterostructured materials for CO2 mitigation and conversion into fuels: a renewable energy approach towards a sustainable environment
Authors: Bhawna  , Kumar Sanjeev , Sharma Ritika , Borah Shikha Jyoti , Gupta Akanksha , Gupta Manoj Kumar , Kumar Ravinder , Dubey Kashyap Kumar , Mishra Yogendra Kumar , Kumar Vinod
Published: July 2023

This review provides an overview of the recent progress in photocatalytic materials for CO2 reduction. The importance of activation strategies is discussed, and we provide insight on the enhancement of the performance of reactors towards reduction of CO2 and conversion to value-added fuels.
Modulation of two-dimensional palladium nanozyme activity to enhance chemodynamic/photothermal combined therapy for melanoma
Authors: Sun Duo , Liu Kaijun , Cheng Yi , Sun Jinju , Fang Jingqin , Tang Yi , Wang Fangyang , Guo Yu , Wang Yi , Chen Xiao
Published: July 2023

Nanozymes are artificial enzymes that mimic natural enzyme-like activities and exhibit tremendous potential for tumor chemodynamic therapy.
Effect of annealing temperature on energy storage performance of Ba(Zr0.35Ti0.65)O3 thin films under pure oxygen
Authors: Sun Yanji , Sun Zheng , Li Xiang , Yue Xipeng , Han Yemei , Xie Yangyang , Hu Kai , Wang Fang , Zhang Kailiang
Published: July 2023

The appropriate annealing temperature under oxygen atmosphere can effectively suppress oxygen vacancies in BZT35 thin films and improve their energy storage performance.
Construction of Co3(PO4)2/g-C3N4 nanowire composites to boost visible-light-driven photocatalysis
Authors: Jiang Haiqin , Li Jinlun , Rao Xi , Zhang Yongping
Published: July 2023

The schematic illustration of photocatalytic hydrogen evolution and removal of bacteria of 15CPO–CN nanocomposites.
The kynurenine pathway of tryptophan metabolism: a neglected therapeutic target of COVID-19 pathophysiology and immunotherapy
Authors: Badawy Abdulla Abu-Bakr
Published: July 2023

SARS-CoV-2 (COVID-19) exerts profound changes in the kynurenine (Kyn) pathway (KP) of tryptophan (Trp) metabolism that may underpin its pathophysiology. The KP is the main source of the vital cellular effector NAD+ and intermediate metabolites that modulate immune and neuronal functions. Trp metabolism is the top pathway influenced by COVID-19. Sixteen studies established virus-induced activation of the KP mediated mainly by induction of indoleamine 2,3-dioxygenase (IDO1) in most affected tissues and of IDO2 in lung by the increased release of proinflammatory cytokines but could additionally involve increased flux of plasma free Trp and induction of Trp 2,3-dioxygenase (TDO) by cortisol. The major Kyn metabolite targeted by COVID-19 is kynurenic acid (KA), the Kyn metabolite with the greatest affinity for the aryl hydrocarbon receptor (AhR), which is also activated by COVID-19. AhR activation initiates two important series of events: a vicious circle involving IDO1 induction, KA accumulation and further AhR activation, and activation of poly (ADP-ribose) polymerase (PARP) leading to NAD+ depletion and cell death. The virus further deprives the host of NAD+ by inhibiting its main biosynthetic pathway from quinolinic acid, while simultaneously acquiring NAD+ by promoting its synthesis from nicotinamide in the salvage pathway. Additionally, the protective effects of sirtuin 1 are minimised by the PARP activation. KP dysfunction may also underpin the mood and neurological disorders acutely and during ‘long COVID’. More studies of potential effects of vaccination therapy on the KP are required and exploration of therapeutic strategies involving modulation of the KP changes are proposed.
Automated Classification of Cognitive Decline and Probable Alzheimer's Dementia Across Multiple Speech and Language Domains
Authors: He Rui , Chapin Kayla , Al-Tamimi Jalal , Bel Núria , Marquié Marta , Rosende-Roca Maitee , Pytel Vanesa , Tartari Juan Pablo , Alegret Montse , Sanabria Angela , Ruiz Agustín , Boada Mercè , Valero Sergi , Hinzen Wolfram
Published: July 2023

Background:

Decline in language has emerged as a new potential biomarker for the early detection of Alzheimer's disease (AD). It remains unclear how sensitive language measures are across different tasks, language domains, and languages, and to what extent changes can be reliably detected in early stages such as subjective cognitive decline (SCD) and mild cognitive impairment (MCI).

Method:

Using a scene construction task for speech elicitation in a new Spanish/Catalan speaking cohort (
N
= 119), we automatically extracted features across seven domains, three acoustic (spectral, cepstral, and voice quality), one prosodic, and three from text (morpholexical, semantic, and syntactic). They were forwarded to a random forest classifier to evaluate the discriminability of participants with probable AD dementia, amnestic and nonamnestic MCI, SCD, and cognitively healthy controls. Repeated-measures analyses of variance and paired-samples Wilcoxon signed-ranks test were used to assess whether and how performance differs significantly across groups and linguistic domains.

Results:

The performance scores of the machine learning classifier were generally satisfactorily high, with the highest scores over .9. Model performance was significantly different for linguistic domains (
p
< .001), and speech versus text (
p
= .043), with speech features outperforming textual features, and voice quality performing best. High diagnostic classification accuracies were seen even within both cognitively healthy (controls vs. SCD) and MCI (amnestic and nonamnestic) groups.

Conclusion:

Speech-based machine learning is powerful in detecting cognitive decline and probable AD dementia across a range of different feature domains, though important differences exist between these domains as well.

Supplemental Material:

https://doi.org/10.23641/asha.23699733
Development of the Adult ECMO Specialist Certification Examination
Authors: Riley Jeffrey B. , Lucas Mark T. , Samolyk Keith A. , Reagor James A. ,   Subject Matter Expert Working Group:, Timpa Joseph G. , Pierce Christopher N. , Preston Thomas J. , Darling Edward M. , Searles Bruce E. , Longenecker Robert D. , Hodge Ashley B. , Charette Kevin A. , Groom Robert C. , Fitzgerald David C. , Sleasman Justin R. , Alwardt Cory M. , Bonadonna Desiree K. , Shepard Mark P. , Harris William E.
Published: July 2023

The American Society of Extracorporeal Technology Board of Directors, consistent with the American Society of Extracorporeal Technology’s safe patient care improvement mission, charged the International Board of Blood Management to write a knowledge and skill certification examination for healthcare personnel employed as adult extracorporeal membrane oxygenation (ECMO) specialists. Nineteen nationally recognized ECMO subject-matter experts were selected to complete the examination development. A job analysis was performed, yielding a job description and examination plan focused on 16 job categories. Multiple-choice test items were created and validated. Qualified ECMO specialists were identified to complete a pilot examination and both pre- and post-examination surveys. The examination item difficulty and candidate performance were ranked and matched using Rasch methodology. Candidates’ examination scores were compared with their profession, training, and experience as ECMO specialists. The 120-item pilot examination form ranked 76 ECMO specialist candidates consistent with their licensure, ECMO training, and clinical experience. Forty-three registered nurses, 28 registered respiratory therapists, four certified clinical perfusionists, and one physician assistant completed the pilot examination process. Rasch statistics revealed examination reliability coefficients of .83 for candidates and .88 for test items. Candidates ranked the appropriateness for examination items consistent with the item content, difficulty, and their personal examination score. The pilot examination pass rate was 80%. The completed examination product scheduled for enrollment in March 2020 includes 100 verified test items with an expected pass rate of 84% at a cut score of 67%. The online certification examination based on a verified job analysis provides an extramural assessment that ranks minimally prepared ECMO specialists’ knowledge, skills, and abilities (KSA) consistent with safe ECMO patient care and circuit management. It is anticipated that ECMO facilities and ECMO service providers will incorporate the certification examination as part of their process improvement, safety, and quality assurance plans.
Using a Modified CPD Blood Bag to Store Blood from either ECMO or RRT Circuit Blood in Pediatric Patients
Authors: Neal James R. , Friedrich Tammy P. , Schears Gregory J. , Cramer Carl H.
Published: July 2023

By adapting a citrate phosphate dextrose (CPD) whole blood storage bag, residual blood from a renal replacement therapy (RRT) circuit can be saved in pediatric patients, decreasing in donor exposure later. The techniques used for autologous preoperative blood storage are the basis of storing the RRT circuit blood. The CPD anticoagulant has a benefit of having a commonly used reversal agent for its anticoagulant properties, i.e., calcium. Also, unlike the traditional anticoagulants used in extracorporeal membrane oxygenation (ECMO), i.e., heparin, and direct thrombin inhibitors, i.e., bivalirudin, there is no increase in anticoagulation laboratory parameters after administration. The CPD volume in the bag is reduced but keeps the original ratio the same between CPD and blood. This is accomplished by removing all CPD from the bag, adding back only the exact amount of CPD needed for the smaller amount of blood being transferred from the circuit. The RRT circuit managed at our institution uses 23 mL of CPD for 165 mL of circuit blood when stored with this technique. This calculation assumes a normal patient calcium level. This technique has been used successfully multiple times in more than 30 pediatric patients without incident for 7 years at our center. The CPD bag can also be used to store the residual blood from ECMO circuits after removal of ECMO to allow the blood to be given back to the patient at a later time by keeping the same citrate-to-blood ratio.
Psychische Folgen intensivmedizinischer Behandlung von COVID-19 bei
Patienten und Angehörigen
Authors: Schuster Mathilda , Deffner Teresa , Rosendahl Jenny
Published: July 2023

Ziel der Studie Es wurden behandlungs- und krankheitsassoziierte Folgen
einer intensivmedizinischen Behandlung von COVID-19 für Patient:innen
und Angehörige untersucht und mit Daten der Allgemeinbevölkerung
sowie mit Sepsis-Patient:innen verglichen. Darüber hinaus wurden
dyadische Assoziationen in der Belastung von Patient:innen und
Angehörigen analysiert.

Methodik In einer monozentrischen, prospektiven, nicht-kontrollierten
Beobachtungsstudie wurden Patient:innen, die aufgrund einer COVID-19-Erkrankung
im Zeitraum November 2020 bis März 2021 im Universitätsklinikum
Jena intensivmedizinisch behandelt werden mussten, sowie deren
Angehörige im Zeitraum von drei bis sechs Monaten nach Entlassung von
der Intensivstation (ITS) befragt. Langzeitfolgen wurden mit der Hospital
Anxiety and Depression Scale, der Posttraumatischen Stressskala-14, dem
Multidimensional Fatigue Inventory-10 und mittels des EQ-5D-5L erhoben.

Ergebnisse Es wurden 72 Patient:innen (Mdn 64 Jahre, 67%
Männer) und 56 Angehörige (Mdn 60 Jahre, 80% Frauen,
80% (Ehe-)Partner:innen) in die Studie eingeschlossen. 39,4% der
Patient:innen berichteten klinisch relevante Angstsymptome, 38,8%
Depressivitätssymptome und 45,1% PTBS-Symptome, wobei in den
meisten Fällen auffällige Werte in mehreren Symptombereichen
vorlagen. Bei den Angehörigen wies ein geringerer Anteil
auffällige Werte auf
(29,2%/15,3%/31,5%). Verglichen mit der
Allgemeinbevölkerung berichteten COVID-19-Patientinnen und -Patienten
signifikant höhere Angst- und Erschöpfungswerte sowie eine
reduzierte Lebensqualität. Bei den Angehörigen zeigten sich
signifikant höhere Angstwerte für Frauen und eine geringere
Lebensqualität für Männer. Im Vergleich zu
ITS-Patient:innen mit schwerer Sepsis fanden sich bei COVID-19-Patient:innen
signifikant höhere PTBS-Symptome und eine geringere
Lebensqualität. Signifikante dyadische Assoziationen zeigten sich
für Angst und Fatigue.

Diskussion Die Ergebnisse dieser Studie zur psychischen Belastung nach
ITS-Behandlung bestätigen Befunde aus vorherigen Untersuchungen, deuten
aber auch auf eine stärkere PTBS-Symptomatik hin, die sich durch das
erhöhte Traumatisierungspotential von Isolations- und
Schutzmaßnahmen während der Behandlung erklären
lässt. Im Vergleich zur Allgemeinbevölkerung fallen besonders
erhöhte Angstwerte der Patient:innen auf, die durch die mögliche
Gefahr einer Re-Infektion begründbar sind.

Schlussfolgerung Psychische Langzeitfolgen der intensivmedizinischen
Behandlung einer COVID-19-Erkrankung sollten in der ambulanten Nachversorgung
der Betroffenen diagnostiziert und adäquat adressiert werden.
Welche Versorgungserwartungen haben Rehabilitand*innen mit
Migrationshintergrund im Verlauf der medizinischen Rehabilitation? –
Eine qualitative Befragung
Authors: Yilmaz-Aslan Yüce , Aksakal Tuğba , Langbrandtner Jana , Deck Ruth , Razum Oliver , Brzoska Patrick
Published: July 2023

Hintergrund Menschen mit Migrationshintergrund sind im Vergleich zu
Menschen ohne Migrationshintergrund mit ihrer Versorgung durchschnittlich
unzufriedener und weisen ungünstigere Rehabilitationsergebnisse auf.
Gründe hierfür werden u. a. in einer mangelnden
interkulturellen Öffnung von Rehabilitationseinrichtungen vermutet. Auch
unerfüllte Versorgungserwartungen hinsichtlich der Gestaltung von
Rehabilitationsangeboten können dazu führen, dass rehabilitative
Angebote erst spät und mit großen Vorbehalten in Anspruch
genommen werden, und auch der Rehabilitationsprozess selbst
beeinträchtigt wird. Über die Erwartungen, die Menschen mit
Migrationshintergrund an die Versorgung haben und darüber, wie sie sich
im Verlauf der Rehabilitation verändern, ist bisher nur wenig bekannt.
Ziel der vorliegenden Studie ist es, Versorgungserwartungen exemplarisch bei
Menschen mit türkischem Migrationshintergrund im Rehabilitationsverlauf
zu untersuchen.

Methodik Die Untersuchung basiert auf leitfadengestützten
Einzelinterviews mit 32 Menschen mit türkischem Migrationshintergrund zu
drei unterschiedlichen Phasen des Rehabilitationsprozesses, die in fünf
Rehabilitationseinrichtungen in Nordrhein-Westfalen und Schleswig-Holstein
durchgeführt wurden. Die Auswertung der Daten erfolgte mittels
inhaltlich-strukturierender qualitativer Inhaltsanalyse.

Ergebnisse Die Versorgungserwartungen von Rehabilitand*innen mit
Migrationshintergrund sind individuell sehr unterschiedlich. Viele Befragte
erhofften sich von der Rehabilitation vor allem eine Verbesserung der
gesundheitlichen Situation, Schmerzlinderung und Erholung. Darüber
hinaus äußerten sie den Wunsch nach einer individuellen
Behandlung und einer intensiven ärztlichen Betreuung während der
Rehabilitation. Die zu Beginn der Rehabilitation formulierten
Versorgungserwartungen verändern sich teilweise im Verlauf der
Rehabilitation, werden den befragten Rehabilitand*innen zufolge aber
nicht oder nur teilweise erfüllt. Gründe für die
Nichterfüllung liegen u. a. in einer unzureichenden
ärztlichen Betreuung während der Rehabilitation.

Schlussfolgerung Aus den Befragungen werden sehr vielfältige
Erwartungen von Menschen mit türkischem Migrationshintergrund an die
Rehabilitation deutlich, was sich durch die Heterogenität dieser
Bevölkerungsgruppe erklärt. Die Ergebnisse weisen auf Potenziale
und Ansatzpunkte zur Weiterentwicklung der rehabilitativen Versorgung in einer
vielfältigen Gesellschaft hin. Diversitätssensible Instrumente,
die der Vielfalt aller Rehabilitand*innen Rechnung tragen
können, können hierbei einen wertvollen Beitrag leisten.
Hypnotherapie und Verhaltenstherapie bei Depressionen –
Ergebnisse der Dreieinhalb-Jahres-Katamnese einer randomisiert-kontrollierten
Nicht-Unterlegenheitsstudie
Authors: Fuhr Kristina , Beier Victoria Maren , Meisner Christoph , Batra Anil
Published: July 2023

Ziel der Studie Die wissenschaftliche Anerkennung der Hypnotherapie ist
für bestimmte psychische Störungen immer noch nicht
bestätigt. Im Rahmen einer randomisiert-kontrollierten Studie, die die
Wirksamkeit der Hypnotherapie (HT) mit der Kognitiven Verhaltenstherapie (KVT)
bei leichten bis mittelschweren depressiven Episoden verglich, konnte eine
Nicht-Unterlegenheit der HT gegenüber der KVT gefunden werden. Ziel
dieser Studie war die Untersuchung der depressiven Symptomatik im
Langzeitverlauf dreieinhalb Jahre nach Behandlungsende.

Methodik Die insgesamt 152 randomisierten Patientinnen und Patienten
hatten über einen Zeitraum von sechs Monaten ambulante
Einzelpsychotherapiesitzungen mit 16 bis 20 Sitzungen erhalten. Dreieinhalb
Jahre nach Behandlungsende wurden alle zu einer Nachbefragung eingeladen, bei
der depressive Symptome im Selbst- und Fremdurteil erfasst wurden. In die
Per-Protokoll (PP) Analyse wurden nur die Personen mit vorhandenen Daten
eingeschlossen, es erfolgte jedoch ein Vergleich der Merkmale mit Personen ohne
eine Teilnahme an der Nachbefragung. Eine zusätzliche Intention-to-treat
(ITT) Analyse wurde mit multipel imputierten Daten der fehlenden Werte
durchgeführt.

Ergebnisse Insgesamt 71 Personen (46,7%) nahmen an der erneuten
Befragung teil. Die Nicht-Unterlegenheit der HT im Vergleich zur KVT bezogen auf
die prozentuale Symptomverbesserung im Fremdurteil konnte in der PP-, aber auch
in der ITT-Stichprobe bestätigt werden. Die Symptomverbesserungen im
Selbst- und Fremdurteil bei Therapieende blieben bei der Nachbefragung bestehen.
Responseraten und Remissionsraten werden für das Selbst- als auch die
Fremdurteile berichtet.

Schlussfolgerung In dieser Studie konnten Hinweise darauf gefunden werden,
dass die HT auch langfristig der KVT bei der Behandlung von Depressionen nicht
unterlegen war. Weitere Studien sollten die Wirksamkeit der HT an
größeren multizentrischen Stichproben untersuchen sowie
Prädiktoren für einen individuellen Therapieerfolg
identifizieren.
Standard-Dose Azithromycin in Class III Obese Patients Undergoing Unscheduled Cesarean Delivery
Authors: Hopkins Maeve K. , Tewari Surabhi , Yao Meng , DeAngelo Lydia , Buckley Lauren , Rogness Victoria , Kollikonda Swapna , Goje Oluwatosin
Published: July 2023

Objective Perioperative antibiotic prophylaxis reduces cesarean wound complications. This study investigates whether integration of standard-dose (500 mg) azithromycin prophylaxis reduced wound complications in patients with class III obesity (body mass index [BMI] ≥ 40 kg/m2) undergoing unscheduled cesarean delivery.

Study Design Retrospective cohort study of patients with class III obesity undergoing unscheduled cesarean delivery in single hospital system from January 1, 2017, to January 1, 2020. A standard dose (500 mg) of azithromycin was integrated into system order sets in 2018. Medical history and postoperative wound outcomes were compared in pre- and postintegration cohorts. Wound complication was defined as composite of wound seroma, hematoma, superficial or deep infection.

Results A total of 1,273 patients met inclusion criteria, 303 patients in the preorder set group, and 970 patients in the postorder set group. Demographics were similar between the pre- and postintegration cohorts, including BMI (median: 44.4 kg/m2, p = 0.84) and weight at delivery (mean: 121.2 ± 17.8 kg, p = 0.57). Patients in the postintegration cohort had lower rates of composite postpartum wound complication (7.9 vs. 13.9%, p = 0.002), superficial infection or deep infection/abscess (6.7 vs. 10.2%, p = 0.042), and postpartum readmission or unscheduled visits (18.7 vs. 24.4%, p < 0.029). Rates of chorioamnionitis and endometritis were similar between the pre- and postintegration groups (8.6 vs. 6.9%, p = 0.33, and 1.7 vs. 1.9%, p = 0.81, respectively). Patients in the postintegration cohort had lower risk of postoperative composite wound complication (unadjusted odds ratio [OR]: 0.54, confidence interval [CI]: 0.36–0.80, p = 0.002) and lower rates of wound infection (unadjusted OR: 0.63, 95% CI: 0.40–0.99, p = 0.044). When comparing patients who received azithromycin at delivery and patients who did not, standard-dose azithromycin reduced risk of postoperative wound complication (unadjusted OR: 0.67, 95% CI: 0.46–0.99, p = 0.043).

Conclusion A standard dose of azithromycin provides adequate perioperative prophylaxis in class III obese patients, decreasing rates of postcesarean wound complications and unscheduled postpartum outpatient visits.

Key Points
Frequency-dependent reflection of a misaligned beam by a Fabry–Pérot cavity
Authors: Cahuzac Aline , Gross Mathieu , Capocasa Eleonora , Barsuglia Matteo , Flaminio Raffaele , La Penna Paolo
Published: July 2023

Gravitational-wave detectors, such as Virgo, LIGO, and KAGRA, are modified Michelson interferometers, with a system of coupled Fabry–Pérot cavities, to increase its sensitivity and bandwidth. In order to control the detector, several radio frequency sidebands, not resonant in the kilometric arm cavities but resonant in the central cavities of the interferometer, are added to the carrier frequency to extract longitudinal and alignment error signals. Misalignment of the laser in the Fabry–Pérot cavities causes sensitivity degradation through different mechanisms and results in non-superposition of carrier and sidebands. These relative misalignment between fields at different frequency contain clues to optimally align the interferometer, but the question of the direction of a reflected beam by a Fabry–Pérot cavity, as a function of the state of resonance of the incoming electromagnetic field, is neither straightforward nor intuitive. While numerical optical simulations used in the gravitational-wave detector community are able to answer the question, they do not give a qualitative and handy understanding of the observed phenomenon, useful for the commissioning and operation of the detectors. In this Letter, we present a model based on Gaussian beam first-order modal expansion to calculate analytically how misalignment on the input beam in a Fabry–Pérot cavity translates into misalignment of the reflected and circulating beams. We find a strong dependence not only on the beam resonance condition but also on the mirror geometry. Finally, we checked the consistency of our model by comparing its predictions with existing numerical simulators.
Charge equilibration model with shielded long-range Coulomb for reactive molecular dynamics simulations
Authors: Nwankwo Udoka , Wang Yi-Di , Lam Chi-Hang , Onofrio Nicolas
Published: July 2023

Atomic description of electrochemical systems requires reactive interaction potential to explicitly describe the chemistry between atoms and molecules and the evolving charge distribution and polarization effects. Calculating Coulomb electrostatic interactions and polarization effects requires a better estimate of the partial charge distribution in molecular systems. However, models such as reactive force fields and charge equilibration (QEq) include Coulomb interactions up to a short-distance cutoff for better computational speeds. Ignoring long-distance electrostatic interaction affects the ability to describe electrochemistry in large systems. We studied the long-range Coulomb effects among charged particles and extended the QEq method to include long-range effects. By this extension, we anticipate a proper account of Coulomb interactions in reactive molecular dynamics simulations. We validate the approach by computing charges on a series of metal-organic frameworks and some simple systems. Results are compared to regular QEq and quantum mechanics calculations. The study shows slightly overestimated charge values in the regular QEq approach. Moreover, our method was combined with Ewald summation to compute forces and evaluate the long-range effects of simple capacitor configurations. There were noticeable differences between the calculated charges with/without long-range Coulomb interactions. The difference, which may have originated from the long-range influence on the capacitor ions, makes the Ewald method a better descriptor of Coulomb electrostatics for charged electrodes. The approach explored in this study enabled the atomic description of electrochemical systems with realistic electrolyte thickness while accounting for the electrostatic effects of charged electrodes throughout the dielectric layer in devices like batteries and emerging solid-state memory.
Pattern formation in slot-die coating
Authors: Kasischke Maren , Hartmann Simon , Niermann Kevin , Smarra Marco , Kostyrin Denis , Thiele Uwe , Gurevich Evgeny L.
Published: July 2023

We experimentally study the occurrence of pattern formation during the slot-die coating of partially wetting liquids onto polyethylenterephthalat-substrates outside the coating window. The experimental investigation is supported by numerical simulations of a dynamical model. Our results demonstrate that beyond a critical coating speed, the deposition of homogeneous coating layers undergoes an instability resulting in the self-organized emergence of patterned coatings, i.e., stripes of different orientation and droplet patterns. We investigate the transitions between the different patterns as triggered by changes in the control parameters inherent to slot-die coating, e.g., the liquid viscosity and the coating gap height. The relatively simple theoretical approach is based on lubrication theory. It is already able to reproduce most of the patterns observed experimentally and reveals a wettability-driven instability mechanism.
Magnetic saturation enhancement of gold-capped nickel nanorods
Authors: Galindo Arturo , Reyes-Rodríguez José Luis , Mendoza-Ramirez Miriam Carolina , Moreno Mario , Carlos Netzahualcoyotl , Ponce Arturo
Published: July 2023

Nickel nanorods (NRs) capped with gold (Au/Ni) were grown into porous anodic aluminum oxide templates and subsequently transferred onto Au/Si (100) substrates. A high dense 2D array of Ni and Au/Ni nanorods was analyzed by vibrating sample magnetometry; it was found that an increase in 14.8% of the magnetic moment following the deposition of Au caps. In order to further investigate this phenomenon, the magnetic distribution of Au/Ni nanorods was studied by off-axis electron holography. The magnetization and induction strengths were evaluated to be 4.7 × 105 A/m and 0.62 T, respectively, which is equivalent to magnetometry measurements of the Ni NR arrays. Remarkably, a vortex state configuration was imaged in the Au segment by the retrieved magnetic phase of the electron holograms under free lens conditions of the transmission electron microscope column. It was concluded that the magnetic distribution in the Au segment is associated with a ferromagnetic coupling with Ni and correlated with the magnetometry measurements.
A relativistic configuration interaction method with general expansions and initial applications to electronic g-factors
Authors: Nyvang Andreas , Olsen Jeppe
Published: July 2023

A new implementation of the orbital-based two-component relativistic configuration interaction approach is reported and applied to calculations of the electronic g-shifts of three diatomic radicals: AlO, HgF, and PdH. The new implementation augments efficient routines for the calculation of nonrelativistic Hamiltonians with new vectorized routines for the calculation of the action of the one-electron spin–orbit operator and allows efficient calculations for the expansion of generalized active space type. The program makes full use of double group as well as time-reversal symmetry. Particle–hole reorganization of the operators is used to improve the efficiency for expansions with nearly fully occupied orbital spaces. The flexibility of the algorithm and program is used to investigate the convergence of electronic g-shifts for the three diatomic radicals as functions of the active space, states included in the orbital optimization, and excitation levels. It was possible to converge to the valence limits within a few percent using expansions containing up to quadruple excitations. However, when excitations from the core orbitals were added, it was not possible to demonstrate convergence to within a few percent with expansions containing at most 10 × 109 determinants.
Stark control of electrons across the molecule–semiconductor interface
Authors: Garzón-Ramírez Antonio J. , Franco Ignacio
Published: July 2023

Controlling matter at the level of electrons using ultrafast laser sources represents an important challenge for science and technology. Recently, we introduced a general laser control scheme (the Stark control of electrons at interfaces or SCELI) based on the Stark effect that uses the subcycle structure of light to manipulate electron dynamics at semiconductor interfaces [A. Garzón-Ramírez and I. Franco, Phys. Rev. B 98, 121305 (2018)]. Here, we demonstrate that SCELI is also of general applicability in molecule–semiconductor interfaces. We do so by following the quantum dynamics induced by non-resonant few-cycle laser pulses of intermediate intensity (non-perturbative but non-ionizing) across model molecule–semiconductor interfaces of varying level alignments. We show that SCELI induces interfacial charge transfer regardless of the energy level alignment of the interface and even in situations where charge exchange is forbidden via resonant photoexcitation. We further show that the SCELI rate of charge transfer is faster than those offered by resonant photoexcitation routes as it is controlled by the subcycle structure of light. The results underscore the general applicability of SCELI to manipulate electron dynamics at interfaces on ultrafast timescales.
Gamma irradiation of Ge-doped and radiation-hard silica fibers at cryogenic temperatures: Mitigating the radiation-induced attenuation with 1550 and 970 nm photobleaching
Authors: Schuyt J. J. , Duke O. , Moseley D. A. , Ludbrook B. M. , Salazar E. E. , Badcock R. A.
Published: July 2023

We investigated the effects of gamma irradiation on radiation-induced attenuation (RIA) in photosensitive (Ge-doped) and radiation-hard (F-doped) fibers at cryogenic temperatures (77 K) under different photobleaching conditions. We show that increasing the probe power (1550 nm) and injecting lower wavelength light (970 nm) both resulted in a significant reduction in RIA in both fiber types, where radiation-hard fibers were intrinsically more resistant to the RIA. Deconvolution of RIA growth curves revealed that the RIA was composed of transient and long-term growth components that were correlated with distinct radiation-induced defects specific to each fiber composition. The 1550 nm light more effectively suppressed the transient RIA, while 970 nm more effectively suppressed the long-term RIA. Ultimately, we show that cryogenic RIA may be effectively managed in fiber optic sensing systems using radiation-hard fibers and dual-wavelength photobleaching strategies.
Annealing of blue quantum emitters in carbon-doped hexagonal boron nitride
Authors: Chen Yongliang , Gale Angus , Yamamura Karin , Horder Jake , Condos Alexander , Watanabe Kenji , Taniguchi Takashi , Toth Milos , Aharonovich Igor
Published: July 2023

Reliable methods to create quantum emitters in hexagonal boron nitride (hBN) are highly sought after for scalable applications in quantum photonic devices. Specifically, recent efforts have focused on defects in hBN with a zero phonon line at 2.8 eV (436 nm). Here, we employ carbon-doped hBN crystals that were irradiated by an electron beam to generate these emitters and perform annealing treatments to investigate the stability of the emitters. We find that the blue emitters are stable up to ∼800 °C. However, upon annealing to 1000 °C, the emitters disappear, and a family of other emitters appears in the region of hBN that had been irradiated by an electron beam. Our findings contribute to the understanding of emitter species and emitter formation in hBN.
Copper oxide memristor as artificial synapses emulating Hebbian symmetric and asymmetric learning behavior for neuromorphic computing beyond von Neumann architecture
Authors: Prakash Chandra , Dixit Ambesh
Published: July 2023

Beyond von Neumann’s architecture, artificial neural network-based neuromorphic computing in a simple two-terminal resistive switching device is considered the future potential technology for simultaneous data processing and storage. These are also compatible with low-power consumption nanoelectronic devices and, thus, suitable for applications such as image recognition toward solving complex pattern recognition problems. Herein, motivated by the human biological brain, we successfully synthesized low-cost RRAM devices using the thermal oxidation of Cu, i.e., CuO as the active material together with Cu as the top electrode and FTO as the bottom contact for a two-terminal resistive switching device, and investigated characteristics for neuromorphic computing. Cu/CuO/FTO-based devices showed excellent bipolar analog RRAM characteristics with 150 repeatable cycles, retention for 11 000 s, and DC pulse endurance for 5000 cycles. Moreover, devices exhibit a remarkable mimicking ability, demonstrating spike time-dependent plasticity (STDP), pulse-paired facilitation (PPF), synaptic weight, and learning and forgetting characteristics, substantiating the recognition ability. Furthermore, the artificial neural network synaptic membrane exhibits excellent long-term (LTP) and short-term (STP) potentiation for six consecutive cycles. Thus, the present work on Cu/CuO/FTO-based devices provides a detailed understanding of CuO active material-based resistive switching with a potential for neuromorphic computing beyond the von Neumann architecture.
The effect of chemical constitution on polyisoprene dynamics
Authors: Ghanta Rohit , Burkhart Craig , Polińska Patrycja , Harmandaris Vagelis , Doxastakis Manolis
Published: July 2023

Polyisoprene (PI) melts have been studied, with most reports focusing on systems with high 1,4-cis content. In contrast, 1,4-trans PI homopolymers or random copolymers have seldom been examined, despite a handful of investigations suggesting a distinct dynamic behavior. Herein, we employ all-atom simulations to investigate the effect of chemical architecture on the dynamics of cis and trans-PI homopolymers, as well as copolymers. We examine the thermodynamic, conformational, and structural properties of the polymers and validate the performance of the models. We probe chain dynamics, revealing that cis-PI presents accelerated translation and reorientation modes relative to trans as recorded by the mean square displacement of the chain center-of-mass as well as by the characteristic times of the lower modes in a Rouse analysis. Interestingly, progressing to higher modes, we observe a reversal with trans units exhibiting faster dynamics. This was further confirmed by calculations of local carbon–hydrogen vector reorientation dynamics, which offer a microscopic view of segmental mobility. To obtain insight into the simulation trajectories, we evaluate the intermediate incoherent scattering function that supports a temperature-dependent crossover in relative mobility that extends over separations beyond the Kuhn-length level. Finally, we analyzed the role of non-Gaussian displacements, which demonstrate that cis-PI exhibits increased heterogeneity in dynamics over short-timescales in contrast to trans-PI, where deviations persist over times extending to terminal dynamics. Our all-atom simulations provide a fundamental understanding of PI dynamics and the impact of microstructure while providing important data for the design and optimization of PI-based materials.
Simulation of rarefied gas flows using physics-informed neural network combined with discrete velocity method
Authors: Zhang Linying , Ma Wenjun , Lou Qin , Zhang Jun
Published: July 2023

The linearized Bhatnagar–Gross–Krook equation is widely used to describe low-speed rarefied gas flows and can be solved numerically using deterministic methods such as the discrete velocity method (DVM). With the help of physics-informed neural networks (PINNs), which have experienced rapid development in recent years, we develop a new surrogate model that combines the PINNs and DVM methods (PINN–DVM) to simulate rarefied gas flows. In the proposed PINN–DVM model, the linearized Bhatnagar–Gross–Krook equation is directly encoded into the residual of an artificial neural network. A new loss function for the boundary condition based on the impermeable diffusion model is proposed to accurately capture the velocity slip and temperature jump at the boundary. PINN–DVM overcomes the limitations of conventional numerical methods, such as complex mesh generation and derivative calculations. Furthermore, the proposed model is enhanced by a self-adaptive strategy based on the neural tangent kernel, which enables the loss weight for each component of the loss function to be adjusted adaptively. Four representative numerical cases of Couette flow, Fourier heat transfer flow, triangular duct flow, and cavity flow demonstrate the superiority of the proposed PINN–DVM model in solving rarefied gas flows compared with original PINNs.
RF loss reduction by a carbon-regulated Si substrate engineering in GaN-based HEMT buffer stacks
Authors: Cai Zidong , Yang Xuelin , Shen Zhaohua , Ma Cheng , Chen Zhenghao , Liu Danshuo , Xu Fujun , Tang Ning , Wang Xinqiang , Ge Weikun , Shen Bo
Published: July 2023

A carbon-regulated Si substrate engineering has been adopted to reduce the RF loss of GaN-based HEMT buffer stacks. By implanting the substrate with high-dose carbon, undersaturation of Si self-interstitials is formed, and the self-interstitial-assisted aluminum diffusion into the Si substrate during the growth can be significantly suppressed. Consequently, the formation of parasitic conductive channel is suppressed, and the RF loss of the buffer stacks can be reduced. By combining the substrate engineering with low-temperature growth, the RF loss of the buffer stacks is reduced to as low as 0.13 dB/mm at 10 GHz. In addition, the crystal quality of the buffer stacks grown on the regulated substrates does not degrade. This work shows a great potential for fabrication of high-quality and low-loss GaN-on-Si RF devices.
Spin- and angle-resolved photoemission spectroscopy study of heptahelicene layers on Cu(111) surfaces
Authors: Baljozović M. , Arnoldi B. , Grass S. , Lacour J. , Aeschlimann M. , Stadtmüller B. , Ernst K.-H.
Published: July 2023

It has been demonstrated previously that electrons interact differently with chiral molecules depending on their polarization. For enantiomeric pure monolayers of heptahelicene, opposite asymmetries in spin polarization were reported and attributed to the so-called chirality-induced spin selectivity effect. However, these promising proof-of-concept photoemission experiments lack the angular and energy resolution that could provide the necessary insights into the mechanism of this phenomenon. In order to fill in the missing gaps, we provide a detailed spin- and angle-resolved photoemission spectroscopy study of heptahelicene layers on a Cu(111) substrate. Throughout the large accessible energy and angle range, no chirality induced spin asymmetry in photoemission could be observed. Possible reasons for the absence of signatures of the spin-dependent electron transmission through the chiral molecular layer are briefly discussed.
High-performance Ta2O5-based resistive random-access memory with embedded graphene quantum dots and Pt–Ag composite active layer
Authors: Wang Renzhi , Chang Ke , Zhao Xinhui , Yu Xinna , Ma Saiqun , Zhao Zhuyikang , Wang Hui
Published: July 2023

Resistive random-access memory (RRAM) has garnered significant interest in developing nonvolatile memory systems due to its ability to provide external field tunable resistive states with fast speed and low power consumption. This tunable resistive state primarily results from the formation and breakage of conductive pathways triggered by active ion migration. However, due to the stochastic nature of ion migration, the stability of the switching process is a long-standing bottleneck. Here, we investigate the impact of device kinetic parameters on the stability of resistive switching behavior and propose a high-performance RRAM with a Pt–Ag/Ta2O5/GQDs/Pt structure. Incorporating quantum dots can regulate the direction of Ag ion migration, while the Pt–Ag composite electrode can manipulate the oxidation rate of Ag atoms. Compared to the Ag/Ta2O5/GQDs/Pt device, the Pt–Ag/Ta2O5/GQDs/Pt device exhibited a 15-fold reduction in operating voltage, a 10-fold increase in on/off ratio, and superior endurance and uniformity. These findings demonstrate that tuning kinetic parameters has the potential to enhance resistive switching performance, which offers an effective pathway for designing high-performance memory systems.
A time-dependent quantum approach to dissociative recombination, associative ionization, and Penning ionization
Authors: Yang Dongzheng , Guo Hua
Published: July 2023

A time-dependent wave packet method is introduced for calculating the integral and differential cross sections for the dissociative recombination (DR), associative ionization (AI), and Penning ionization (PI) processes. This method is demonstrated for DR/AI of the N + O ↔ NO+ + e− system and PI for the He* + Ar → He + Ar+ + e− system. Good agreement with previous theoretical and experimental results is obtained for these DR, AI, and PI processes. This method has the potential to provide a quantitative characterization of polyatomic ionization-involved processes on multidimensional potential energy surfaces.
Highly sensitive strain sensor based on tapered few-mode fiber
Authors: Li Li , Jiang Chao , Hu Chuanju , Gao Jiawei , Deng Longfeng , Cao Tingshui , Li Hong
Published: July 2023

A high sensitivity strain sensor using a sandwich structure of “single mode fiber (SMF)—few mode fiber (FMF)—single mode fiber (SMF)” was proposed and experimentally validated. The designed sensor is achieved by splicing a segment of FMF between two segments of SMFs, and then using a fiber optic fusion tapering machine to double the length of FMF. Introducing tapered optical fibers into the structure to excite more evanescent waves improves the sensitivity of the sensor to the surrounding environment. In addition, due to the fact that the FMF is tapered into a very fine shape, the tensile stress applied to the FMF will increase. Therefore, conical FMF has excellent stress concentration ability, which is easily deformed under stress, thus achieving a high strain sensitivity of −23.9 pm/με. Finally, a cascaded FBG was used to compensate for the temperature cross-sensitivity of the sensor. This strain sensor with an extremely simple structure and high sensitivity has wide application value in the industry.
Investigation of energy dissipation mechanism and the influence of vortical structures in a high-power double-suction centrifugal pump
Authors: Deng Qifan , Pei Ji , Wang Wenjie , Sun Ju
Published: July 2023

The extensive applications of double-suction centrifugal pumps consume a considerable amount of energy. It is urgent to reveal the detailed energy dissipation generation and find the critical factor for pump performance enhancement. In this investigation, the internal flow field of a double-suction centrifugal pump was obtained by solving the Reynolds averaged Navier–Stokes equations. The entropy production method was utilized to calculate and visualize irreversible energy dissipation. The Omega vortex method was utilized to identify vortical structures and determine the temporal and spatial relationship between entropy production and vortices. The results indicate that the entropy production in the main flow regions was critical in hydraulic loss, accounting for 54%–71% of the loss, and turbulent dissipation in the main flow regions of the impeller and volute casing dominated the variation of pump efficiency. The near-wall entropy production in the impeller positively correlated with the flow rate, but the impact was insignificant in volute casing. Although the suction chamber contributed minimally to the hydraulic loss, the backflows at the impeller inlet were relieved near the ribs, and the dissipation at the impeller inlet was reduced when the blade leading edges passed the ribs. By adopting Omega vortex identification, wake vortices, separation vortices, and their interactions were determined to correlate strongly with hydraulic loss in volute channels and near cutwaters. Furthermore, these vortices were influenced by the back flows from the impeller sidewall gaps. Additionally, this study can also provide the foundational principles for the optimal design of this type of pump.
Initial platelet aggregation in the complex shear environment of a punctured vessel model
Authors: Spieker Christian J. , Závodszky Gábor , Mouriaux Clarisse , Mangin Pierre H. , Hoekstra Alfons G.
Published: July 2023

To analyze flow conditions and cellular behavior at the onset of a hemostatic response in the injury of a microneedle-induced vessel puncture, a combined in silico and in vitro platform is created. A cell-resolved blood flow model is utilized for in-depth flow profile and cell distribution analyses, and a novel punctured vessel flow chamber is set up to complement the simulations with the evaluation of platelet aggregation around the wound neck of the puncture. The respective setups of the platform are explained, and the results of both experiments and simulations with various puncture diameters and pressure drops are combined, providing detailed insight into the basic processes of platelet transport and aggregation in the wound area. A special emphasis of the simulation evaluation is put on the cell distributions and the magnitude of shear rate and elongational flow in the wound neck area, as well as downstream from the puncture. Additionally, possible implications of wound size and pressure difference on the hemostatic response are discussed. The simulations display asymmetric cell distributions between the proximal and distal sides of the wound neck in regard to the flow direction. The flow chamber with the puncture diameter closest to the simulated domains confirms this asymmetry by displaying increased platelet aggregation at the wound neck's distal side. The presented punctured vessel in silico and in vitro experimental setups offer a platform to analyze the hemostatic environment of a vessel injured by a puncture and might assist in identifying differentiating factors between primary hemostasis and arterial thrombosis.