bluuebunny/crossref_metadata_2025 huggingface dataset:
Corneal Microaneurysm—A Vascular Feature of Conjunctival Squamous Intraepithelial Neoplasia
Authors: Stöckl Victoria , Franchi Alexander , Palme Christoph , Steger Bernhard
Published: April 2024

Purpose:

The diagnosis of conjunctival squamous intraepithelial neoplasia (CSIN) can be difficult because of the heterogeneous appearance. Despite established risk factors and diagnostic support by high-resolution optical coherence tomography (hrOCT) and indocyanine green angiography (ICGA), the only reliable diagnostic method is a histological work-up. This case report is the first to describe corneal microaneurysms in CSIN as a vascular feature for conjunctival tumor angiogenesis.

Methods:

An 84-year-old male patient was referred with a suspected diagnosis of pterygium. Biomicroscopic examination revealed a whitish epithelial lesion of conjunctival origin with centripetal corneal growth and extension over 5 limbal hours. Intralesional vascularization showed highly altered morphology with aneurysmal changes. After imaging with hrOCT and ICGA, excision was performed in a “no-touch double-freeze and thaw” technique, followed by histological and immunohistochemical work-up.

Results:

hrOCT showed an epithelial, hyperreflective lesion with a maximum thickness of 272 µm and sharp central border. ICGA confirmed active perfusion and partial thrombosis of the aneurysmal terminal vascular buds dilated to 405 μm with early dye leakage within the first minute. Histological examination confirmed the clinical diagnosis of CSIN with focal high-grade dysplasia. Postoperatively, there was no recurrence during the observation period of 5 months.

Conclusions:

Intralesional terminal microaneurysms are a feature of tumor angiogenesis in CSIN. The relevance and frequency of this potential new risk factor for malignancy should be investigated in further studies.
Reflecting on diagnosis: The Metacognitive Diagnostic Reasoning Model©
Authors: Beebe Sarah L. , McNelis Angela M. , El-Banna Majeda , Dreifuerst Kristina Thomas
Published: April 2024

Background:

Diagnostic reasoning is a complex cognitive process that requires intuitive, heuristic processing from knowledge and experience, as well as deliberate and reflective thinking. Evidence on interventions to improve diagnostic reasoning is inconsistent, in part because different terms and models are used to guide research.

Purpose:

To present a model of the factors of diagnostic reasoning in Advanced Practice Registered Nurses (APRNs), based on a review of the literature supporting the Metacognitive Diagnostic Reasoning (MDR) Model©.

Methodology:

A review of the literature through systematic database search, historical articles, texts, and documents was conducted from inception through August 2023 (N = 41).

Results:

The MDR model depicts the following concepts: (1) metacognition is viewed as the driving force of diagnostic reasoning; (2) dual cognitive processing and knowledge representations are used; (3) once a diagnosis, treatment plan, and evaluation are complete, APRNs use metacognition for the next patient encounter, using repetition for improvement of the process.

Conclusions:

The model combines key concepts of diagnostic reasoning, providing a framework for researchers to develop and test, and faculty to teach and evaluate this complex process in learners.

Implications:

The MDR model provides research opportunities to validate its usefulness and effectiveness and a framework to guide educational research, contributing to the body of evidence-based practice in nursing. In addition, it may foster ongoing education and training that could lead to more accurate diagnoses and treatment plans, ultimately improving patient care by reducing diagnostic errors.
Correlation Analysis Between Echinocytosis Stages and Blood Viscosity During Oxygenator Perfusion: An In Vitro Study
Authors: Okahara Shigeyuki , Miyamoto Satoshi , Soh Zu , Yoshino Masaru , Takahashi Hidenobu , Itoh Hideshi , Tsuji Toshio
Published: April 2024

The study aimed to investigate the effect of red blood cell (RBC) morphology on oxygenator perfusion, focusing on stages of echinocytosis and their correlation with blood viscosity. A test circuit with an oxygenator and human RBC mixtures was used to induce changes in RBC shape by increasing sodium salicylate concentrations (0, 10, 20, 30, 60, and 120 mmol/L), while hematocrit, blood temperature, and anticoagulation were maintained. Blood viscosity was measured using a continuous blood viscosity monitoring system based on pressure-flow characteristics. Under a scanning electron microscope, the percentages of discocytes, echinocytes I–III, spheroechinocytes, and spherocytes were determined from approximately 400 cells per RBC sample. Early echinocytes, mainly discocytes and echinocytes I and II in the range of 0–30 mmol/L were predominant, resulting in a gradual increase in blood viscosity from 1.78 ± 0.12 to 1.94 ± 0.12 mPa s. At 60 mmol/L spherocytes emerged, and at 120 mmol/L, spheroidal RBCs constituted 50% of the population, and blood viscosity sharply rose to 2.50 ± 0.15 mPa s, indicating a 40% overall increase. In conclusion, the presence of spherocytes significantly increases blood viscosity, which may affect oxygenator perfusion.
Impact of the New Heart Allocation System on the Medium-Term Outcomes in Patients With Hypertrophic Cardiomyopathy
Authors: Mazur Matylda , Carmona Rubio Andres , Eisen Howard J. , Bhat Geetha , Dowling Robert
Published: April 2024

The introduction of the new heart allocation system in the United States in 2018 resulted in an increase in the number of heart transplants (HT) performed among patients with hypertrophic cardiomyopathy (HCM). However, whether that affected medium-term post-HT outcomes in this group of patients remains unknown. We conducted an analysis of the United Network for Organ Sharing Transplant Database, including adults with HCM who underwent heart transplantation between 2015 and 2021. Patients were divided into two equal-duration eras: Era 1 (October 17, 2015, to October 17, 2018) and Era 2 (October 18, 2018, to October 18, 2021). In the studied period, 444 patients with HCM underwent HT: 204 in Era 1 and 240 in Era 2. In Era 2, the waitlist time was shorter, transplant rates were higher, patients were less frequently supported with inotropes but more often with an IABP, ischemic time was longer, and donor-to-recipient distance larger. Pre- and post-transplant functional status was comparable across the two eras, while the pre-HT employment rate was higher in the new system. The 3 year survival was unchanged across eras. In the new allocation system, despite more frequent mechanical circulatory support (MCS) use and increased ischemic time, the medium-term outcomes of patients with HCM remained favorable.
Plantar pressure analysis of different orthoses in patients after first metatarsophalangeal joint arthrodesis
Authors: Golden Dana , Corbett R. O. , Cooper Minton Truitt , Hertel Jay
Published: April 2024

Background:

There is no gold standard for a walking orthosis after first metatarsophalangeal joint (MTPJ) arthrodesis surgery. Evaluation of plantar pressure measures and patient perceptions for different orthoses may assist surgeons to choose a postsurgery orthotic. The purpose of this study was to measure plantar pressure under the distal first ray during walking and patient perceptions of comfort, stability, and preference with 4 different orthoses in patients with a history of first MTPJ arthrodesis.

Methods:

Crossover study in a university laboratory. Eleven patients volunteered (8 female, 3 male, age = 59.4 ± 9.1 years, 21.9 ± 17.5 months since surgery) who had a unilateral first MTPJ arthrodesis procedure more than 6 months before study participation. Four orthosis conditions were evaluated in all participants: patient's shoe, carbon fiber insert, OrthoWedge, and Post-Op Shoe. We analyzed peak plantar pressure and pressure–time integral under the whole foot and the distal first ray as well as recorded subjective rating for comfort and stability. Rank ordered for preferred orthosis.

Results:

OrthoWedge had significantly lower whole-foot and distal first ray peak pressure than the other conditions. The pressure–time integral for the OrthoWedge was significantly less than the Carbon Fiber Insert and Post-Op Shoe. For stability, comfort, and condition preference, the OrthoWedge was ranked lowest among the 4 conditions.

Conclusions:

The OrthoWedge generated the lowest peak plantar pressure but was subjectively ranked as the least preferred orthosis. This discrepancy between objective biomechanical and subjective comfort measures must be weighed as surgeons prescribe an orthosis to patients after first MTPJ arthrodesis.
Brief Report: Nasal colonization with Staphylococcus aureus and Methicillin resistant Staphylococcus aureus among community-dwelling older adults with comorbidities seeking follow-up medical care in Central Sri Lanka.
Authors: Iqbal Ifaaz , Sabri Zeenath , Illangasinghe Adithya , Isurindi Ashini , Jayakodi Rashmi , Jayasekara Wasana , Jayarathna Kaveesha , Jayasinghe Nanduni , Ishani Mekhala , Jayasekara Ishan , Handapangoda Nelum , Menike Dilrukshi , Dissanayake Rasadanie , Ekanayake Asela , Liyanapathirana Veranja
Published: April 2024

Older adults are more severely affected by infections caused by drug-resistant bacteria including Methicillin-Resistant Staphylococcus aureus (MRSA). We aimed to identify the MRSA colonization rates and associated factors among older adults aged more than 65-years-old. Among the 309 recruited, 152 (49.2%) were males. Self-collected nasal swabs were used to isolate Staphylococcus aureus and MRSA with routine microbiological methods. Staphylococcus aureus was isolated from 36 (11.7%) participants while 11 (3.6%) were colonized with MRSA. We identified a significant association between the male sex and MRSA colonization (p=0.028, Chi-square test). However, this needs careful interpretation given the smaller number of outcome events. Other factors studied had no statistically significant association with MRSA colonization.
Impact of automated data flow and reminders on adherence and resource utilization for remotely monitoring physical activity in individuals with stroke or chronic obstructive pulmonary disease
Authors: French Margaret A. , Balasubramanian Aparna , Hansel Nadia N. , Penttinen Sharon K. , Wise Robert , Raghavan Preeti , Wegener Stephen T , Roemmich Ryan T. , Celnik Pablo A.
Published: April 2024

As rehabilitation advances into the era of digital health, remote monitoring of physical activity via wearable devices has the potential to change how we provide care. However, uncertainties about patient adherence and the significant resource requirements needed create challenges to adoption of remote monitoring into clinical care. Here we aim to determine the impact of a novel digital application to overcome these barriers. The Rehabilitation Remote Monitoring Application (RRMA) automatically extracts data about physical activity collected via a Fitbit device, screens the data for adherence, and contacts the participant if adherence is low. We compare adherence and estimate the resources required (i.e., time and financial) to perform remote monitoring of physical activity with and without the RRMA in two patient groups. Seventy-three individuals with stroke or chronic obstructive pulmonary disease completed 28 days of monitoring physical activity with the RRMA, while 62 individuals completed 28 days with the data flow processes being completed manually. Adherence (i.e., the average percentage of the day that the device was worn) was similar between groups (p=0.85). However, the RRMA saved an estimated 123.8 minutes or $50.24 per participant month when compared to manual processes. These results demonstrate that automated technologies like the RRMA can maintain patient adherence to remote monitoring of physical activity while reducing the time and financial resources needed. Applications like the RRMA can facilitate the adoption of remote monitoring in rehabilitation by reducing barriers related to adherence and resource requirements.
FicD regulates adaptation to the unfolded protein response in the murine liver
Authors: Casey Amanda K. , Stewart Nathan M , Zaidi Naqi , Gray Hillery F. , Cox Amelia , Fields Hazel A. , Orth Kim
Published: April 2024

The unfolded protein response (UPR) is a cellular stress response that is activated when misfolded proteins accumulate in the endoplasmic reticulum (ER). The UPR elicits a signaling cascade that results in an upregulation of protein folding machinery and cell survival signals. However, prolonged UPR responses can result in elevated cellular inflammation, damage, and even cell death. Thus, regulation of the UPR response must be tuned to the needs of the cell, sensitive enough to respond to the stress but pliable enough to be stopped after the crisis has passed. Previously, we discovered that the bi-functional enzyme FicD can modulate the UPR response via post-translational modification of BiP. FicD AMPylates BiP during homeostasis and deAMPylates BiP during stress. We found this activity is important for the physiological regulation of the exocrine pancreas. Here, we explore the role of FicD in the murine liver. Like our previous studies, livers lacking FicD exhibit enhanced UPR signaling in response to short term physiologic fasting and feeding stress. However, the livers ofFicD−/−did not show marked changes in UPR signaling or damage after either chronic high fat diet (HFD) feeding or acute pathological UPR induction. Intriguingly,FicD−/−mice showed changes in UPR induction and weight loss patterns following repeated pathological UPR induction. These findings show that FicD regulates UPR responses during mild physiological stress and may play a role in maintaining resiliency of tissue through adaptation to repeated ER stress.
A genomic history of the North Pontic Region from the Neolithic to the Bronze Age
Authors: Nikitin Alexey G. , Lazaridis Iosif , Patterson Nick , Ivanova Svitlana , Videiko Mykhailo , Dergachev Valentin , Kotova Nadiia , Lillie Malcolm , Potekhina Inna , Krenz-Niedbała Marta , Łukasik Sylwia , Makhortykh Serhij , Renson Virginie , Shephard Henry , Sirbu Gennadie , Svyryd Sofiia , Tkachuk Taras , Włodarczak Piotr , Callan Kim , Curtis Elizabeth , Harney Eadaoin , Iliev Lora , Kearns Aisling , Lawson Ann Marie , Michel Megan , Mah Matthew , Micco Adam , Oppenheimer Jonas , Qiu Lijun , Workman J. Noah , Zalzala Fatma , Mallick Swapan , Rohland Nadin , Reich David
Published: April 2024

The north Black Sea (Pontic) Region was the nexus of the farmers of Old Europe and the foragers and pastoralists of the Eurasian steppe1,2, and the source of waves of migrants that expanded deep into Europe3–5. We report genome-wide data from 78 prehistoric North Pontic individuals to understand the genetic makeup of the people involved in these migrations and discover the reasons for their success. First, we show that native North Pontic foragers had ancestry not only from Balkan and Eastern hunter-gatherers6but also from European farmers and, occasionally, Caucasus hunter-gatherers. More dramatic inflows ensued during the Eneolithic, when migrants from the Caucasus-Lower Volga area7moved westward, bypassing the local foragers to mix with Trypillian farmers advancing eastward. People of the Usatove archaeological group in the Northwest Pontic were formed ca. 4500 BCE with an equal measure of ancestry from the two expanding groups. A different Caucasus-Lower Volga group, moving westward in a distinct but temporally overlapping wave, avoided the farmers altogether, and blended with the foragers instead to form the people of the Serednii Stih archaeological complex7. A third wave of expansion occurred when Yamna descendants of the Serednii Stih forming ca. 4000 BCE expanded during the Early Bronze Age (3300 BCE). The temporal gap between Serednii Stih and the Yamna expansion is bridged by a genetically Yamna individual from Mykhailivka in Ukraine (3635-3383 BCE), a site of uninterrupted archaeological continuity across the Eneolithic-Bronze Age transition, and the likely epicenter of Yamna formation. Each of these three waves propagated distinctive ancestries while also incorporating outsiders during its advance, a flexible strategy forged in the North Pontic region that may explain its peoples’ outsized success in spreading their genes and culture across Eurasia3–5,8–10.
mRNA localization and thylakoid protein biogenesis in the filamentous heterocyst-forming cyanobacterium Anabaena sp. PCC 7120
Authors: Wang Kexin , Mahbub Moontaha , Mastroianni Giulia , Mullineaux Conrad W
Published: April 2024

Heterocyst-forming cyanobacteria such as Anabaena (Nostoc) sp. PCC 7120 exhibit extensive remodeling of their thylakoid membranes during heterocyst differentiation. Here we investigate the sites of translation of thylakoid membrane proteins in Anabaena vegetative cells and developing heterocysts, using mRNA fluorescent in situ hybridization to detect the location of specific mRNA species. We probed mRNAs encoding reaction center core components and the heterocyst-specific terminal oxidases Cox2 and Cox3. As in unicellular cyanobacteria, we find that the mRNAs encoding membrane-integral thylakoid proteins are concentrated in patches at the inner face of the thylakoid membrane system, adjacent to the central cytoplasm. These patches mark the putative sites of translation and membrane insertion of these proteins. Oxidase activity in mature heterocysts is concentrated in the specialized "honeycomb" regions of the thylakoid membranes close to the cell poles. However, cox2 and cox3 mRNAs remain evenly distributed over the inner face of the thylakoids, implying that oxidase proteins migrate extensively after translation to reach their destination in the honeycomb membranes. The RNA binding protein RbpG is the closest Anabaena homolog of Rbp3 in the unicellular cyanobacterium Synechocystis sp. PCC 6803, which we previously showed to be crucial for the correct location of photosynthetic mRNAs. An rbpG null mutant shows decreased cellular levels of photosynthetic mRNAs and photosynthetic complexes, coupled with perturbations to thylakoid membrane organization and lower efficiency of the Photosystem II repair cycle. This suggests that chaperoning of photosynthetic mRNAs by RbpG is important for the correct co-ordination of thylakoid protein translation and assembly.
Alligamycin A, an unprecedented antifungal β-lactone spiroketal macrolide fromStreptomyces iranensis
Authors: Yang Zhijie , Qiao Yijun , Strøbech Emil , Morth Jens Preben , Walther Grit , Jørgensen Tue Sparholt , Lum Kah Yean , Peschel Gundela , Rosenbaum Miriam A. , Previtali Viola , Clausen Mads Hartvig , Lukassen Marie Vestergaard , Gotfredsen Charlotte Held , Kurzai Oliver , Weber Tilmann , Ding Ling
Published: April 2024

Fungal infections pose a great threat to public health and there are limited antifungal medicaments.Streptomycesis an important source of antibiotics, represented by the clinical drug amphotericin B. The rapamycin-producerStreptomyces iranensisharbors an unparalleled Type I polyketide synthase, which codes for a novel antifungal macrolide alligamycin A (1), the structure of which was confirmed by NMR, MS, and X-ray crystallography. Alligamycin A harbors an undescribed carbon skeleton with 13 chiral centers, featuring a (β-lactone moiety, a [6,6]-spiroketal ring, and an unprecedented 7-oxo-octylmalonyl-CoA extender unit incorporated by a potential novel crotonyl-CoA carboxylase/reductase. Thealibiosynthetic gene cluster was confirmed through CRISPR-based gene editing. Alligamycin A displayed profound antifungal effects against numerous clinically relevant filamentous fungi, includingTalaromycesandAspergillusspecies. (β-Lactone ring is essential for the antifungal activity and alligamycin B (2) with disruption in the ring abolished the antifungal effect. Proteomics analysis revealed alligamycin A potentially disrupted the integrity of fungal cell walls and induced the expression of stress-response proteins inAspergillus niger. Alligamycins represent a new class of potential drug candidate to combat fungal infections.
A shift from pleiotropic to modular adaptation revealed by a high-resolution two-step adaptive walk
Authors: Kinsler Grant , Li Yuping , Sherlock Gavin , Petrov Dmitri A.
Published: April 2024

Evolution by natural selection is expected to be a slow and gradual process. In particular, the mutations that drive evolution are predicted to be small and modular, incrementally improving a small number of traits. However, adaptive mutations identified early in microbial evolution experiments, cancer, and other systems often provide substantial fitness gains and pleiotropically improve multiple traits at once. We asked whether such pleiotropically adaptive mutations are common throughout adaptation or are instead a rare feature of early steps in evolution that tend to target key signaling pathways. To do so, we conducted barcoded second-step evolution experiments initiated from five first-step mutations identified from a prior yeast evolution experiment. We then isolated hundreds of second-step mutations from these evolution experiments, measured their fitness and performance in several growth phases, and conducted whole-genome sequencing of the second-step clones. Here, we found that while the vast majority of mutants isolated from the first-step of evolution in this condition show patterns of pleiotropic adaptation - improving both performance in fermentation and respiration growth phases - second-step mutations show a shift towards modular adaptation, mostly improving respiration performance and only rarely improving fermentation performance. We also identified a shift in the molecular basis of adaptation from genes in cellular signaling pathways towards genes involved in respiration and mitochondrial function. Our results suggest that the genes in cellular signaling pathways are particularly capable of providing large, adaptively pleiotropic benefits to the organism due to their ability to coherently affect many phenotypes at once. As such, these genes may serve as the source of pleiotropic adaptation in the early stages of evolution, and once these become exhausted, organisms then adapt more gradually, acquiring smaller, more modular mutations.
TPR is required for cytoplasmic chromatin fragment formation during senescence
Authors: Bartlett Bethany M. , Kumar Yatendra , Boyle Shelagh , Chowdhury Tamoghna , Quintanilla Andrea , Boumendil Charlene , Acosta Juan Carlos , Bickmore Wendy A.
Published: April 2024

During oncogene-induced senescence there are striking changes in the structure of the nucleus and the organisation of heterochromatin. This is accompanied by activation of a pro-inflammatory gene expression programme – the senescence associated secretory phenotype (SASP) – driven by transcription factors such as NF-κB. Here we show that TPR, a protein of the nuclear pore complex basket, is required for the very early activation of NF-κB signalling during the stress-response phase of oncogene-induced senescence. This is prior to activation of the SASP and occurs without affecting NF-κB nuclear import. We show that TPR is required for the activation of TBK1 signalling at these early stages of senescence and we link this to the formation of heterochromatin-enriched cytoplasmic chromatin fragments thought to bleb off from the nuclear periphery. These cytoplasmic chromatin fragments appear to lack nuclear pore components. Our data suggest that TPR at the nuclear pore is involved in the loss of structural integrity of the nuclear periphery during senescence. We propose that this acts as a trigger for activation of cytoplasmic nucleic acid sensing, NF-κB signalling, and activation of the SASP, during senescence.
Revised Hamiltonian near third-integer resonance and implications for an electron storage ring
Authors: Nam Ki Moon , Hwang Ji-Gwang , Yoon Young Dae , Parc Yong Woon
Published: April 2024

In electron storage rings, an accurate description of particle dynamics near third-integer resonance is crucial for various applications. The conventional approach is to extrapolate far-resonance dynamics to near resonance, but the difficulty arises because the nonlinear detuning parameter diverges at this critical point. Here we derive, via a suitable application of the canonical perturbation theory, a revised detuning parameter that is well behaved near resonance. The resultant theory accurately describes the morphology of resonance islands for a wide range of parameter space and facilitates its optimization.

Published by the American Physical Society
2024
Quantum simulation approach to implementing nuclear density functional theory via imaginary time evolution
Authors: Li Yang Hong , Al-Khalili Jim , Stevenson Paul
Published: April 2024

The quantum imaginary time evolution (QITE) algorithm is a direct implementation of the classical imaginary time evolution algorithm on quantum computer. We implement the QITE algorithm for the case of nuclear Hartree-Fock equations in a formalism equivalent to nuclear density functional theory. We demonstrate the algorithm in the case of the helium-4 nucleus with a simplified effective interaction of the Skyrme kind and demonstrate that the QITE, as implemented on simulated quantum computer, gives identical results to the classical algorithm.

Published by the American Physical Society
2024
Higgs boson width and couplings at high energy muon colliders with forward muon detection
Authors: Li Peiran , Liu Zhen , Lyu Kun-Feng
Published: April 2024

We propose a novel method using the ZZ-fusion channel and forward muon detection at high energy muon colliders to address the challenge of the Higgs coupling-width degeneracy. Our approach enables inclusive Higgs rate measurement to 0.75% at 10 TeV muon collider, breaking the coupling-width degeneracy. Results indicate the potential to refine Higgs coupling to subpercent levels and estimate its total width within (−0.41%, +2.1%). Key insights include the effectiveness of forward muon tagging in signal-background separation despite broad recoil mass distribution due to muon energy reconstruction and beam energy spread. The study emphasizes the significance of muon rapidity coverage up to |η(μ)|<6, enhancing measurement precision. Our findings highlight the unique capabilities of high energy lepton colliders for model-independent Higgs coupling determination and lay the groundwork for future advancements in muon collider technology and Higgs physics research.

Published by the American Physical Society
2024
Ringdowns for black holes with scalar hair: The large mass case
Authors: D’Addario Giovanni , Padilla Antonio , Saffin Paul M. , Sotiriou Thomas P. , Spiers Andrew
Published: April 2024

Deviations from general relativity can alter the quasinormal mode (QNM) ringdown of perturbed black holes. It is known that a shift-symmetric (hence massless) scalar can only introduce black hole hair if it couples to the Gauss-Bonnet invariant, in which case the scalar charge is fixed with respect to the black hole mass and controlled by the strength of that coupling. The charge per unit mass decreases with the mass and can, therefore, be used as a perturbative parameter for black holes that are sufficiently large with respect to the scale suppressing the deviation from general relativity or the Standard model. We construct an effective field theory scheme for QNMs using this perturbative parameter to capture deviations from Kerr for both the background and the perturbations. We demonstrate that up to second order in the charge per unit mass, QNMs can be calculated by solving standard linearized perturbation equations for the Kerr metric with sources depending on solutions of the same equations up to first order. It follows that corrections to the QNM frequencies are heavily suppressed for sufficiently massive black holes, meaning that LISA is very unlikely to detect any evidence of scalar hair in ringdown signals.

Published by the American Physical Society
2024
Scalable Circuits for Preparing Ground States on Digital Quantum Computers: The Schwinger Model Vacuum on 100 Qubits
Authors: Farrell Roland C. , Illa Marc , Ciavarella Anthony N. , Savage Martin J.
Published: April 2024

The vacuum of the lattice Schwinger model is prepared on up to 100 qubits of IBM’s Eagle-processor quantum computers. A new algorithm to prepare the ground state of a gapped translationally invariant system on a quantum computer is presented, which we call “scalable circuits ADAPT-VQE” (SC-ADAPT-VQE). This algorithm uses the exponential decay of correlations between distant regions of the ground state, together with ADAPT-VQE, to construct quantum circuits for state preparation that can be scaled to arbitrarily large systems. These scalable circuits can be determined with use of classical computers, avoiding the challenging task of optimizing parameterized circuits on a quantum computer. SC-ADAPT-VQE is applied to the Schwinger model, and is shown to be systematically improvable, with an accuracy that converges exponentially with circuit depth. Both the structure of the circuits and the deviations of prepared wave functions are found to become independent of the number of spatial sites, L. This allows a controlled extrapolation of the circuits, determined with use of small or modest-sized systems, to arbitrarily large L. The circuits for the Schwinger model are determined on lattices up to L=14 (28 qubits) with the Qiskit classical simulator, and are subsequently scaled up to prepare the L=50 (100 qubits) vacuum on IBM’s 127-superconducting-qubit quantum computers ibm_brisbane and ibm_cusco. After introduction of an improved error-mitigation technique, which we call “operator decoherence renormalization”, the chiral condensate and charge-charge correlators obtained from the quantum computers are found to be in good agreement with classical matrix product state simulations.

Published by the American Physical Society
2024
Effects of online and offline social capital on social self-efficacy and online self-disclosure
Authors: Wang Edward Shih-Tse , Lin Hung-Chou
Published: April 2024

Purpose

In this study, we drew on the theories of social exchange and social learning and hypothesized that the online social capital (SC) and offline SC of social networking affect the online self-disclosure (OSD) of individuals through social self-efficacy (SSE).

Design/methodology/approach

After retrieving 514 valid questionnaires, we used structural equation modeling to analyze the data.

Findings

The results indicated that the users’ SSE affected their OSD, and that both online and offline bridging and bonding SC increased their SSE. However, online bonding SC directly affected their OSD, whereas online bridging SC did not considerably affect their OSD. Given these findings, we presented both theoretical and practical implications to elucidate SSE and OSD behavior from the perspective of online and offline bridging and bonding SC.

Originality/value

In this study, we drew on theories of social exchange and social learning to examine the effects of online and offline bridging and bonding SC on users’ SSE and OSD on SNSs. Given the importance of SC and SSE in social relationships and the effects of OSD on SNSs, our goal was to provide SNS marketers with a thorough understanding of how to facilitate SSE and OSD from the perspective of online and offline bridging and bonding SC.
Do corporate site visits by analysts and institutional investors increase labor investment efficiency?
Authors: Li Wenfei , Tang Zhenyang , Chen Chufen
Published: April 2024

Purpose

Corporate site visits increase labor investment efficiency.

Design/methodology/approach

Our empirical model for the baseline analysis follows those of Jung et al. (2014) and Ghaly et al. (2020).

Findings

We show that corporate site visits are associated with significantly higher labor investment efficiency; more specifically, site visits reduce both over-hiring and under-hiring of employees. The effect of site visits on labor investment efficiency is more pronounced for firms with higher labor adjustment costs, greater financial constraints, weaker corporate governance and lower financial reporting quality. We also find that site visits mitigate labor cost stickiness.

Originality/value

First, while the literature has suggested how the presence of institutional investors and analysts may affect labor investment decisions, we focus on institutional investors and analysts’ activities and interactions with firm executives. We provide direct evidence that institutional investors and analysts may use corporate site visits to improve labor investment efficiency. Second, our study adds to a line of recent studies on how corporate site visits reduce information asymmetry and agency conflicts. We show that corporate site visits allow institutional investors and analysts to influence labor investment efficiency. We also provide new evidence that corporate site visits reduce labor cost stickiness.
Prototyping of compliant grippers using FFF and TPU
Authors: Mohsen Hussein Omar Hesham , Aly Mohamed Mohamed Fawzy , Megahed Said
Published: April 2024

Purpose

The purpose of this paper is to investigate the process of fused filament fabrication (FFF) of a compliant gripper (CG) using thermoplastic polyurethane (TPU) material. The paper studies the applicability of different CG designs and the efficiency of some design parameters.

Design/methodology/approach

After reviewing a number of different papers, two designs were selected for a number of exploratory experiments. Using design of experiments (DOE) techniques to identify important design parameters. Finally, the efficiency of the parts was investigated.

Findings

The research finds that a simpler design sacrifices some effectiveness in exchange for a remarkable decrease in production cost. Decreasing infill percentage of previous designs and 3D printing them, out of TPU, experimenting with different parameters yields functional products. Moreover, the paper identified some key parameters for further optimization attempts of such prototypes.

Research limitations/implications

The cost of conducting FFF experiments for TPU increases dramatically with product size, number of parameters studied and the number of experiments. Therefore, all three of these factors had to be kept at a minimum. Further confirmatory experiments encouraged.

Originality/value

This paper addresses an identified need to investigate applications of FFF and TPU in manufacturing functional efficient flexible mechanisms, grippers specifically. While most research focused on designing for increased performance, some research lacks discussion on design philosophy, as well as manufacturing issues. As the needs for flexible grippers vary from high-performance grippers to lower performance grippers created for specific functions/conditions, some effectiveness can be sacrificed to reduce cost, reduce complexity and improve applicability in different robotic assemblies and environments.
The effect of United States commercial airport rate-setting methods on airport bond ratings
Authors: Golkar Bahareh , Lim Siew Hoon , Karanki Fecri
Published: April 2024

Purpose

A major source of external funding for US airports comes from issuing municipal bonds. Credit rating agencies evaluate the bonds using multiple factors, but the judgments behind the ratings are not well understood. This paper examines if airport rate-setting methods affect the bond ratings of US airports.

Design/methodology/approach

Using a set of unbalanced panel data for 58 hub airports from 2010 to 2019, we examine the effect of the rate-setting methods and other airport characteristics on Fitch’s airport bond rating.

Findings

We find that compensatory airports consistently receive a very high bond rating from Fitch. The probability of getting a very high Fitch rating increases by ∼28 percentage points for a compensatory airport. Additionally, the probability of getting a very high rating is about 33 percentage points higher for a legacy hub.

Research limitations/implications

The study uses Fitch bond ratings. Future studies could examine if S&P’s and Moody’s ratings are also influenced by airport rate-setting methods and legacy hub status.

Practical implications

The results uncover the linkage between bond ratings and their determinants for US airports. This information is important for investors when assessing airport creditworthiness and for airport operators as they manage capital project financing.

Originality/value

This is the first study to evaluate the effects of rate-setting methods on airport bond rating and also the first to document a statistically significant relationship between airports’ legacy hub status and bond ratings.
Cognitive load, social values and financial distress: drivers of restructuring decisions
Authors: Balume Fidèle Shukuru , Gajewski Jean-François , Heimann Marco
Published: April 2024

Purpose

This study aims to analyze the effect of cognitive load and social value orientation on managers’ preferences when they face with two types of restructuring choices in financially distressed firms: the first belonging to the family of organizational restructuring (massive layoffs) and the second to the family of financial restructuring (debt increases).

Design/methodology/approach

The authors investigate experimentally the impact of managers’ cognitive load and social value orientation on the decision to restructure leveraged buyout (LBO) firms in financial distress by using either massive layoffs or debt increases.

Findings

By investigating the impact of managers’ cognitive load and social value orientation on the restructuring decision of an LBO firm in financial distress, the research reveals that, on average, cognitively loaded managers prefer massive layoffs over increased debt levels. The massive layoffs seemingly provide a relatively easier way to avoid conflict with influential, residual claimants. In contrast, social value–oriented managers actively avoid massive layoffs and prefer to increase debt.

Research limitations/implications

These results imply that the performance mechanisms emphasized to improve agency relations, for example, in LBOs, have their own limitations during periods of financial distress. This study shows that one of these limits is related to cognitive distortions and personality traits.

Originality/value

In this research, the originality lies in understanding how managers’ internal factors affect their restructuring decision-making, in the case of LBO firms in financial distress.
Unleashing synergy: exploring the impact of experiential learning and component technology on integration implementation strategy in cross-border technological acquisitions
Authors: Hanif Nadia
Published: April 2024

Purpose

Drawing on organizational design theory and organizational learning theory, this paper aims to examine component technology (CT) and the interaction between CT and experiential learning (EL) effects on the degree of integration (DI) of cross-border technological acquisitions.

Design/methodology/approach

Using a sample of 267 firms consisting of 229 acquirer firms who started cross-border technological acquisitions from developed economies and 38 acquirer firms who initiated cross-border technological acquisitions from emerging economies over the period of 1993–2016, this study adopts a value chain framework to measure the acquirers’ acquisition integration degree for the investigation of the effects of CT and the interaction between CT and EL.

Findings

First, this paper finds CT in cross-border technological acquisitions exerting a positive influence on the acquirer firm’s likelihood of the DI implementation, in line with the organizational design theory. Second, in view of organizational learning theory, this study finds EL and the combined effect of CT and EL to have an inverse influence on the DI.

Practical implications

The results imply that the moderating role of EL significantly optimizes decision choices for an acquirer firm for integration implementation strategies in the form of DI, such as full integration (structural integration), partial integration and no integration (structural separation), which appears to be crucial for cross-border technological acquisitions.

Originality/value

This study contributed to international business strategies by shedding light on the importance of the DI for an acquirer firm that undertakes a cross-border technological acquisition with a CT target firm. This study explains why structural integration might be necessary in cross-border technological acquisitions regardless of the costs of disruption it imposes, as well as the contexts in which it becomes less important or unnecessary. The study disclosed that the increase in the likelihood of DI because of CT depends on the EL of the acquisition company in the host country environment and fluctuates with the prior acquisition knowledge and EL of the host country. Combining two cross-border technological acquisition’s literature streams, such as CT and EL, this study enlightens the importance of organizational learning theory and theory of organization design strategic direction making on acquisition integration implementation strategies.
Female digital nomads’ destination experiencescape perspective
Authors: Özoğul Balyali Tuğçe
Published: April 2024

Purpose

Although existing studies provide valuable insight into how destinations create stimuli that support meaningful experiences, perceptions of different experiencescapes in the tourism context remain to be explored. This research aims to explore the experiencescape stimuli of female digital nomads.

Design/methodology/approach

The study adopted a qualitative research method and was structured by combining multiple qualitative data collection tools with a triangulated approach to examining the experiencescape.

Findings

Based on the experiences of female digital nomads toward destinations, their perception of the experiencescape, which includes sensory, functional, social, natural and cultural stimuli, has been revealed. From the explanations regarding the metaphors, the female digital nomads in the research have positive perceptions about destination experiences and are satisfied with being digital nomads.

Research limitations/implications

The fact that the research is the first to focus on digital nomadism and experiencescape and that it reveals the perspective of female digital nomads who share their experiences in virtual communities, which is a research topic that is little emphasized in the literature, is a contribution to the theoretical framework on the subject. The practical contribution is that it will guide studies to improve and re-plan experiences in line with the stimuli emphasized by the female digital nomads studied. The results can play a supporting role in developing the market for female digital nomads.

Originality/value

This research offers a new perspective on exploring female digital nomads' perceptions of the destination experiencescape.
The business case for hospital mobility programs in the veterans health care system: Results from multi‐hospital implementation of the STRIDE program
Authors: Kaufman Brystana G. , Hastings S. Nicole , Meyer Cassie , Stechuchak Karen M. , Choate Ashley , Decosimo Kasey , Sullivan Caitlin , Wang Virginia , Allen Kelli D. , Van Houtven Courtney H.
Published: April 2024

Objective

To conduct a business case analysis for Department of Veterans Affairs (VA) program STRIDE (ASsisTed EaRly MobIlization for hospitalizeD older VEterans), which was designed to address immobility for hospitalized older adults.

Data Sources and Study Setting

This was a secondary analysis of primary data from a VA 8‐hospital implementation trial conducted by the Function and Independence Quality Enhancement Research Initiative (QUERI). In partnership with VA operational partners, we estimated resources needed for program delivery in and out of the VA as well as national implementation facilitation in the VA. A scenario analysis using wage data from the Bureau of Labor Statistics informs implementation decisions outside the VA.

Study Design

This budget impact analysis compared delivery and implementation costs for two implementation strategies (Replicating Effective Programs [REP]+CONNECT and REP‐only). To simulate national budget scenarios for implementation, we estimated the number of eligible hospitalizations nationally and varied key parameters (e.g., enrollment rates) to evaluate the impact of uncertainty.

Data Collection

Personnel time and implementation outcomes were collected from hospitals (2017–2019). Hospital average daily census and wage data were estimated as of 2022 to improve relevance to future implementation.

Principal Findings

Average implementation costs were $9450 for REP+CONNECT and $5622 for REP‐only; average program delivery costs were less than $30 per participant in both VA and non‐VA hospital settings. Number of walks had the most impact on delivery costs and ranged from 1 to 5 walks per participant. In sensitivity analyses, cost increased to $35 per participant if a physical therapist assistant conducts the walks. Among study hospitals, mean enrollment rates were higher among the REP+CONNECT hospitals (12%) than the REP‐only hospitals (4%) and VA implementation costs ranged from $66 to $100 per enrolled.

Conclusions

STRIDE is a low‐cost intervention, and program participation has the biggest impact on the resources needed for delivering STRIDE.

Trial Registration

ClinicalsTrials.gov NCT03300336. Prospectively registered on 3 October 2017.
Can information constraints explain the low efficiency in premium quality rice cultivation? Evidence from smallholder farmers in Bangladesh
Authors: Kubitza Christoph , Veettil Prakashan Chellattan , Gupta Ishika , Krupnik Timothy J.
Published: April 2024

The integration of smallholder farmers into emerging value chains for fine‐grain and aromatic ‘premium quality rice’ (PQR) could prove to be crucial to improving rural livelihoods in Bangladesh, though efforts could be constrained by farmers' differing levels of agronomic knowledge. Based on a pre‐analysis plan, we analyse farmers' ability to efficiently allocate production enhancing inputs in PQR cultivation based on a survey of 1420 farmers in key PQR producing areas. Farmers received a hypothetical budget to allocate to six different inputs advised for efficient production of PQR, mimicking familiar production decisions made seasonally on their own farms. Our results suggest that even without budget or input access constraints farmers tend to inefficiently allocate inputs in PQR in this hypothetical setting. In particular, they tend to overspend on seeds, fertiliser and pesticides. Farmers with better access to agricultural information, such as through PQR specific extension services, conversely reach substantially higher efficiency scores and decided to spend significantly less on fertiliser. Without future adjustments such as more targeted extension services, implied higher production costs will likely lower the profitability of PQR cultivation for smallholder farmers, thereby limiting potential income gains. Besides these economic concerns, excessive input use is associated with environmental externalities. Improved efficiency is therefore desirable from both an economic and environmental standpoint.