bluuebunny/crossref_metadata_2025 huggingface dataset:
Predictors of Bilateral SLN Radiocolloid Detection in Endometrial Carcinoma
Authors: Jankulovska Anamarija , Stojcevski Sasho , Aluloski Igor , Tanturovski Mile , Manevska Nevena , Markova Ana Daneva , Stojanoski Sinisa
Published: December 2023

Introduction Sentinel lymph node (SLN) mapping is an alternative method to conventional lymphadenectomy for nodal status assessment in patients with stage I/II endometrial carcinoma (EC). This study aimed to analyze the potential predictors of unsuccessful bilateral detection of SLN after the application of radiocolloid in EC.

Materials and Methods A prospective, observational, cross-sectional study was performed on 41 patients with EC in preoperative stage I, who underwent SLN mapping after cervical application of 4mCi 99mTc-SENTI-SCINT. The demographic, clinical, and tumor-related data were obtained from the patient's medical records. Univariate analysis was used to analyze the potential factors associated with an unsuccessful bilateral SLN biopsy.

Results The bilateral SLN detection rate of planar lymphoscintigraphy, single photon emission computed tomography/computed tomography, and gamma probe was 29.26, 41.46, and 26.82%, correspondingly. None of the 16 analyzed risk factors showed statistical significance for nonconclusive bilateral SLN biopsy.

Conclusion Larger scale studies are needed to determine the exact risk factors for unsuccessful bilateral mapping of the lymphatic drainage after cervical application of the radiotracers. This will eventually lead to improvement in bilateral SLN detection in EC patients, so unilateral lymphadenectomy could be avoided.
Middle Ear Cavity and Mastoid Neuroendocrine Tumor Presenting as Otomastoiditis with Cholesteatoma: A Clinicoradiological and Histopathological Correlation
Authors: Chalikandy Ashwini , Basu Sandip
Published: December 2023

Neuroendocrine tumors of the middle ear are rare, comprising of less than 2% of primary tumors of the ear. The clinical and imaging findings of these tumors are nonspecific, and histological and immunohistochemical findings are confirmatory. Herein, we present a case of 48-year-old male, presenting with chief complaints of hearing loss of left ear with foul smelling discharge, with the initial clinical impression of otomastoiditis of the middle ear with cholesteatoma and being operated for the same, the final histopathology report inferred it as well-differentiated neuroendocrine tumor grade 1 with Ki-67 index less than 2%. Immunohistochemical examinations demonstrated positive staining of the tumor cells for cytokeratin, synaptophysin and chromogranin A, and negative for smooth muscle actin, desmin, S-100. The biochemical investigations showed raised serum chromogranin A levels. Based upon the findings on anatomical imaging modalities including high-resolution computed tomography temporal bone and magnetic resonance imaging paranasal sinuses (MRI PNS), the lesion was inferred inoperable due to involvement of dura of petrous apex, and therefore he was referred for consideration of peptide receptor radionuclide therapy (PRRT). MRI PNS also showed involvement of the horizontal part of facial nerve, indicating local aggressiveness of the tumor. 68Ga-DOTATATE-PET/CT showed high-grade somatostatin receptor expressing soft tissue lesion involving middle ear and external auditory canal (Krenning's score 4), with low-grade metabolic activity on 18F-FDG-PET/CT. The post-therapy scan following 177Lu-DOTATATE PRRT, showed abnormal tracer concentration at the described site. Due to extreme rarity of this disease entity, it is important to accrue data for accurate diagnosis, proper management, and follow-up.
Prostate Cancer Skeletal Metastasis: A Spontaneous Evolution from Osteolytic to Osteoblastic Morphology without Treatment
Authors: Lawal Ismaheel O. , Bilen Mehmet A. , Halkar Raghuveer K. , Jani Ashesh B. , Schuster David M.
Published: December 2023

Skeletal metastases due to prostate cancer (PCa) are more commonly osteoblastic than osteolytic. In the rarer cases of osteolytic skeletal metastasis of PCa, transition to osteoblastic phenotype occurs following treatment, which indicates successful healing. In this report, we present a case of spontaneous osteolytic to osteoblastic evolution of PCa skeletal metastasis without treatment in a patient with recurrence of PCa. Our patient is a 59-year-old male who had a robotic radical prostatectomy in July 2014 for a T2c adenocarcinoma of the prostate gland (Gleason score = 4 + 3). He had adjuvant pelvic radiotherapy in January 2015 due to prostate-specific antigen (PSA) persistence. PSA began to rise in October 2015. An 18F-fluciclovine positron emission tomography/computed tomography (PET/CT) scan obtained in June 2017 at a PSA of 0.5 ng/mL was negative. Repeat 18F-fluciclovine PET/CT of February 2020 at PSA of 3.72 ng/mL showed prostate bed recurrence and a nonavid osteolytic left inferior pubic ramus lesion. 18F radiohybrid prostate-specific membrane antigen (18F-rhPSMA) PET/CT scan of August 2020 performed as part of an ongoing clinical trial confirmed local prostate bed recurrence with a low-grade radiotracer uptake in the osteolytic left inferior pubic ramus bone lesion. Without salvage therapy, 18F-fluciclovine PET/CT of October 2020 and March 2022 shows progressive sclerosis in the left pubic ramus lesion. An osteolytic to osteoblastic transition of a bone lesion as shown in this patient calls for a rethink in our understanding of untreated PCa skeletal metastasis progression. This case provides novel insight into the understanding of the temporal evolution of skeletal metastasis and calls for further research.
Utility of 18-Flurodeoxyglucose Positron Emission Tomography-Computed Tomography (18FDG PET-CT) in Gallbladder Cancer: Experience from a Tertiary Care Hospital
Authors: Bisht Niharika , Lohia Nishant , Singh Sankalp , Sarin Arti , Mahato Abhishek , Paliwal Dharmesh , Sinha Indranil , Bhatnagar Sharad
Published: December 2023

Introduction Gallbladder cancer (GBC) is one of the most common and aggressive malignancies of the Indo-Gangetic plains. Despite its widespread use in GBC cases, the role of 18-flurodeoxyglucose positron emission tomography-computed tomography (18FDG PET-CT) in the management of this disease is not well defined. In our study, we present the practice trends of the utilization of this investigative modality in our hospital and its benefits in aiding diagnosis, staging, and surveillance for recurrence.

Materials and Methods All cases of suspected and biopsy-proven GBCs who underwent PET-CT at our institute between 2016 and 2019 were retrospectively evaluated for the indication of PET-CT testing and its impact on the management of the case. The indications were classified into three categories: (i) staging and metastatic workup, (ii) response assessment post-chemotherapy, and (iii) post-therapy surveillance of patients.

Results A total of 79 PET-CT scans were carried out during the study period. PET-CT was used for less than one-third of the total patients of GBC presenting at our center. Initial staging and workup (49%) was the most common indication followed by surveillance (28%) and response assessment (23%). PET-CT had a substantially better sensitivity in detecting distant metastases compared to conventional imaging in both initial workup and during follow-up. PET-CT provided additional information in 42% scans that led to change in the management of the patient. As a response assessment tool PET-CT aided not only in evaluating efficacy of therapy but also for documenting progressive disease for patients on therapy.

Conclusion PET-CT is a valuable tool to not only rule out metastatic disease while selecting patients for surgery but also for post-therapy surveillance for recurrence in patients of GBC. Larger prospective studies may help in finally elucidating the exact role of PET-CT in this disease.
Fractura tibial secundaria a osteotomía de la tuberosidad anterior de la tibia: Reporte de tres casos y revisión de la literatura
Authors: Figueroa David , Isla Jorge , Ithriago Minerva , Figueroa Maria Loreto , Orrego Mario
Published: December 2023

Existen múltiples opciones de tratamiento al momento de enfrentarnos al amplio espectro de la patología patelofemoral. Dentro de las patologías más frecuentemente encontradas están la inestabilidad y artrosis patelofemoral. Se han descrito distintos tipos de tratamiento, siendo especialmente relevantes los procedimientos de realineamiento distal. Estas técnicas son efectivas en la mayoría de los casos, pero no están exentas de complicaciones, reportándose en hasta un tercio de los casos.

A continuación presentamos tres casos donde se realizó una osteotomía de la tuberosidad anterior de la tibia como herramienta terapéutica para 2 patologías distintas, en todos los casos se reportó una fractura tibial a nivel de la osteotomía, complicación infrecuente pero que puede tener graves consecuencias en el pronóstico de nuestros pacientes.
No unión de fémur distal secundario a lesiones por armas de fuego; Manejo con técnica de masquelet y revisión de la literatura
Authors: Niehaus Andres Schmidt-Hebbel , Stegmeier Robert Etienne Partarrieu , Croxatto Matías Javier , Garrido Sergio Arellano , Silva Diego Edwards , Burucker Alex Vaisman
Published: December 2023

Introducción Las fracturas expuestas por arma de fuego están en riesgo de presentar una pérdida de tejido óseo significativa. En defectos mayores de 2 cm es poco probable la consolidación. La técnica de membrana inducida (TMI) induce la formación de una membrana que facilita la consolidación. Se presentan dos casos de fractura expuestas por arma de fuego que evolucionaron con no uniones infectadas, defectos óseos y posterior manejo con la TMI.

Presentación de los casos Se presentan dos casos de fractura expuesta de fémur distal, secundarias a herida por arma de fuego. Ambos inicialmente manejados con fijación externa seguida de un clavo endomedular (CEM), que evolucionaron con no unión infectada y defecto óseo de 4 cm. Ambos se manejaron con la TMI, logrando control de la infección y consolidación.

Discusión La TMI fue utilizada de forma exitosa como cirugía de salvataje para defectos óseos secundarios a no unión infectada de fémur. El manejo de defectos óseos es un desafío ya que influye la infección, la pérdida de tejidos blandos, el gap óseo y el potencial de curación de la fractura. La TMI es una alternativa atractiva en el tratamiento de defectos óseos mayores de 2 cm, siendo la reparación independiente del tamaño del defecto y permitiendo controlar infecciones asociadas.

Conclusión La TMI es una técnica de salvataje efectiva para el manejo de defectos óseos por arma de fuego, la cual permite salvar la extremidad, con un manejo integral de los diversos aspectos necesarios a considerar en estos casos.
Macroprudential policy, bank competition and bank risk in East Asia
Authors: Chan Ka Kei , Davis E. Philip , Karim Dilruba
Published: December 2023

We assess the relation of macroprudential policy and competition to bank risk for a sample of 1373 banks from 13 East Asian countries, using the IMF iMaPP dataset of macroprudential policy from 1990 to 2018. To our knowledge, this is the first paper to include both macroprudential policy and individual bank market power, as well as their interaction, as determinants of bank risk. On the one hand, we find direct effects of both macroprudential policy and competition on risk, in line with the existing literature. On the other hand, we detect important interaction effects. Notably in the developing and emerging East Asian countries, the interactions between competition and macroprudential measures often show a lesser response to such measures in terms of risk reduction for banks with more market power. We suggest that this links in turn to ability of such banks to undertake risk-shifting in response to macroprudential policy. We also find for banks in advanced East Asian countries—and in wider samples—some tendency in the long term for banks facing intense competition to take relatively more risks in face of macroprudential measures, in line with the traditional “franchise value” view of bank competition and risk taking. These findings have important implications for regulators.
Modification of Richtmyer–Meshkov instabilities via layered explosive charge design
Authors: Hennessey M. P. , Springer H. K. , Belof J. L.
Published: December 2023

In this numerical study, we investigate the effects of layered high explosive (HE) charge design on Richtmyer–Meshkov instability (RMI) in metal plates with sinusoidal surface features. The detonation wave from the HE induces a shock in the metal target that subsequently interacts with the surface features; this results in vortex formation and ultimately RMI. We seek to modify RMI by altering the detonation wave characteristics. The modification is investigated in a twofold manner: first, by varying the initial design of the unconfined surface of the target and second, by varying the charge design and composition. Within a limited scope of this design space, a wide variety of behaviors related to RMI growth are observed. Mechanistic actions, including exaggerated front curvature, behind these modifications are proposed. Charge designs, which modify RMI the most for a select target design, are then presented.
A tunable high-Q flexible ferroelectric film capacitor for GHz RF applications
Authors: Mao Feilong , Hou Yongqi , Zhu Yifan , Zeng Haohan , Zhang Hui
Published: December 2023

With the development of flexible electronics, flexible tunable capacitors with high dielectric constant, high tunability, and low loss become important components in modern communication. A tunable Ba0.6Sr0.4TiO3 capacitor for radio frequency devices is prepared on a flexible substrate. The capacitor has a dielectric constant greater than 1000, capacitance tunability n exceeding 70%, and minimum loss tangent lower than 0.03 at 500 kHz. The Q factor can be above 103 at the GHz frequency range. These parameter values (especially the Q factor) have been comparable to the rigid substrate tunable capacitor. Meanwhile, the minimum radius of curvature of the flexible tunable capacitor can be 3 mm with stable electrical performances. The flexible tunable capacitor retains its mechanical and electrical stability after 24 000 high-frequency bending cycles, which provides potential uses in bendable, collapsible tunable capacitors at the radio frequency range.
Impact of the unrelaxed vibrational modes on hot-electron transfer
Authors: Pudlak Michal
Published: December 2023

The ultrafast photoinduced electron or exciton transfer was investigated theoretically. The charge separation on the ultrafast time scale results in the unrelaxed vibrational modes that appear in the initial terms of the generalized master equations. Here, the impact of these initial terms on the electron transfer directionality in the open system was evaluated. Moreover, the role of unrelaxed vibrational modes in electron–hole separation was also examined. It was shown that the unrelaxed vibrational modes significantly increase the efficiency of electron–hole separation. This could play a crucial role in the remarkable efficiency of charge separation in biological systems.
Magnetohydrodynamic effects on a pathological vessel: An Euler–Lagrange approach
Authors: Kyriakoudi Konstantina C. , Xenos Michail A.
Published: December 2023

For numerically studying blood flow in a pathological vessel under the influence of a magnetic field, it is necessary to develop an approach that tracks the moving tissue and accounts for interactions between the fluid, the arterial wall, and the magnetic field. The current study discusses a mathematical approach of the fluid's motion under the influence of a magnetic field using fluid mechanics principles. A mixed Euler–Lagrange formulation is introduced to mathematically describe the blood flow in the aneurysm during the entire cardiac cycle. Blood is considered a Newtonian, incompressible, and electrically conducting fluid, subjected to a static and uniform magnetic field. Generalized curvilinear coordinates are used to transform the transport equations into body-fitted geometries and provide a manageable form of equations. The system of equations related to motion consists of a coupled and nonlinear system of partial differential equations (PDEs). The discretization of the PDEs is performed using the finite volume method. The addition of the Lorentz force in the momentum PDEs describes the applied uniform magnetic field in the blood flow. Due to strong coupling and nonlinear terms, a simultaneous solution approach is applied. The results show that the magnetic field strongly influences blood flow, reducing the velocity field q¯ and increasing the pressure drop, Δp.
Skyrmion qubits: Challenges for future quantum computing applications
Authors: Psaroudaki Christina , Peraticos Elias , Panagopoulos Christos
Published: December 2023

Magnetic nano-skyrmions develop quantized helicity excitations, and the quantum tunneling between nano-skyrmions possessing distinct helicities is indicative of the quantum nature of these particles. Experimental methods capable of nondestructively resolving the quantum aspects of topological spin textures, their local dynamical response, and their functionality now promise practical device architectures for quantum operations. With abilities to measure, engineer, and control matter at the atomic level, nano-skyrmions present opportunities to translate ideas into solid-state technologies. Proof-of-concept devices will offer electrical control over the helicity, opening a promising new pathway toward functionalizing collective spin states for the realization of a quantum computer based on skyrmions. This Perspective aims to discuss developments and challenges in this new research avenue in quantum magnetism and quantum information.
Magnetization dynamics and spin-glass-like origins of exchange-bias in Fe–B–Nb thin films
Authors: Masood Ansar , Belova L. , Ström V.
Published: December 2023

The phenomenon of exchange bias has been extensively studied within crystalline materials, encompassing a broad spectrum from nanoparticles to thin-film systems. Nonetheless, exchange bias in amorphous alloys has remained a relatively unexplored domain, primarily owing to their inherently uniform disordered atomic structure and lacking grain boundaries. In this study, we present a unique instance of exchange bias observed in Fe–B–Nb amorphous thin films, offering insights into its origins intertwined with the system's spin-glass-like behavior at lower temperatures. The quantification of exchange bias was accomplished through a meticulous analysis of magnetic reversal behaviors in the liquid-helium temperature range, employing a zero-field cooling approach from various initial remanent magnetization states (±MR). At reduced temperatures, the appearance of asymmetric hysteresis, a hallmark of negative exchange bias, undergoes a transformation into symmetric hysteresis loops at elevated temperatures, underscoring the intimate connection between exchange-bias and dynamic magnetic states. Further investigations into the magnetic thermal evolution under varying probe fields reveal the system's transition into a spin-glass-like state at low temperatures. We attribute the origin of this unconventional exchange bias to the intricate exchange interactions within the spin-glass-like regions that manifest at the interfaces among highly disordered Fe-nuclei. The formation of Fe-nuclei agglomerates at the sub-nanometer scale is attributed to the alloy's limited glass-forming ability and the nature of the thin-film fabrication process. We propose that this distinctive form of exchange bias represents a novel characteristic of amorphous thin films.
Comparison of quantum well structures for room temperature continuous wave 980 nm lasers grown on (001) Si by MOCVD
Authors: Huang Jie , Lin Qi , Luo Wei , Gu Wen , Lin Liying , Lau Kei May
Published: December 2023

We report room temperature (RT) continuous-wave (CW) lasing of quantum well (QW) lasers grown on (001) Si substrates emitting at 980 nm. Two different QW structures, including conventional compressively strained InGaAs/GaAs QWs and strain-compensated InGaAs/GaAs/GaAsP QWs, were investigated. Photoluminescence properties and device performance of both structures on native GaAs and (001) Si substrates are discussed. By adding GaAsP barriers to the InGaAs/GaAs QWs, the lowest threshold current density of ridge waveguide edge-emitting QW lasers obtained on Si is 550 A/cm2, measured on a 10 μm × 2 mm device at RT. The working temperature of the InGaAs/GaAs/GaAsP QW lasers grown on Si can be over 95 °C in the CW mode. This work suggests a feasible approach to improve the 980 nm laser performance on Si for monolithic optoelectronic integration.
Reactivity of radiolytically and photochemically generated tertiary amine radicals towards a CO2 reduction catalyst
Authors: Carr Cody R. , Vrionides Michael A. , Grills David C.
Published: December 2023

Homogeneous solar fuels photocatalytic systems often require several additives in solution with the catalyst to operate, such as a photosensitizer (PS), Brønsted acid/base, and a sacrificial electron donor (SED). Tertiary amines, in particular triethylamine (TEA) and triethanolamine (TEOA), are ubiquitously deployed in photocatalysis applications as SEDs and are capable of reductively quenching the PS’s excited state. Upon oxidation, TEA and TEOA form TEA•+ and TEOA•+ radical cations, respectively, which decay by proton transfer to generate redox non-innocent transient radicals, TEA• and TEOA•, respectively, with redox potentials that allow them to participate in an additional electron transfer step, thus resulting in net one-photon/two-electron donation. However, the properties of the TEA• and TEOA• radicals are not well understood, including their reducing powers and kinetics of electron transfer to catalysts. Herein, we have used both pulse radiolysis and laser flash photolysis to generate TEA• and TEOA• radicals in CH3CN, and combined with UV/Vis transient absorption and time-resolved mid-infrared spectroscopies, we have probed the kinetics of reduction of the well-established CO2 reduction photocatalyst, fac-ReCl(bpy)(CO)3 (bpy = 2,2′-bipyridine), by these radicals [kTEA• = (4.4 ± 0.3) × 109 M−1 s−1 and kTEOA• = (9.3 ± 0.6) × 107 M−1 s−1]. The ∼50× smaller rate constant for TEOA• indicates, that in contrast to a previous assumption, TEA• is a more potent reductant than TEOA• (by ∼0.2 V, as estimated using the Marcus cross relation). This knowledge will aid in the design of photocatalytic systems involving SEDs. We also show that TEA can be a useful radiolytic solvent radical scavenger for pulse radiolysis experiments in CH3CN, effectively converting unwanted oxidizing radicals into useful reducing equivalents in the form of TEA• radicals.
Orbitally compact and loose vortex regions
Authors: Kolář V. , Šístek J.
Published: December 2023

The measure of orbital compactness of the motion of swirling material points inside a vortex is formulated without the assumption of incompressibility. Orbitally compact and loose vortex regions are distinguished. Their boundary is set very permissively and expressed through the introduced measure of orbital compactness. The present analysis is associated with the vortex-identification local trace criterion and explains its limited applicability. The comparison of compact and loose volumetric ratios for selected vortex-identification methods employs numerical data of four flow situations. The investigation shows that some vortex-identification criteria are too permissive, more or less ignoring the inherent vortex property of orbital compactness.
Multiple visible wavelength switchable cascaded self-Raman laser based on selective wave-mixing mechanism
Authors: Duan Yanmin , Zhu Haiyong , Zhang Ge , Tang Dingyuan
Published: December 2023

A diode-pumped solid-state laser with watts-level five switchable wavelengths spanning green to red is first experimentally demonstrated. The selective wave-mixing mechanism was introduced for multiple visible wavelength switchable output. The five visible wavelengths are generated by wave-mixing of the fundamental wave, the first-Stokes wave, and the second-Stokes wave in a Nd:YVO4 self-Raman laser. A β-barium borate crystal with a critical phase-matching angle cut is used for the wavelength conversion, and the angle-tuning method was used to achieve fast wavelength switching. A diffusion bonded YVO4/Nd:YVO4/YVO4 crystal was used to reduce the thermal lens effect and increase the effective length of the Raman gain medium for high output power and efficient Raman conversion. Under a pump power of 19.5 W, five visible laser output powers achieved for the green at 532 nm, lime at 559 nm, yellow at 588 nm, orange-red at 620 nm, and deep red at 657 nm are 4.01, 1.76, 2.54, 1.41, and 2.82 W, respectively. This laser system provides a convenient way for visible wavelength-switchable coherent light generation and may find potential applications where multiple visible wavelengths are required.
Battery-less luminance sensor biomimicking human sensory nervous system
Authors: Yamada S. , Toshiyoshi H.
Published: December 2023

With the evolution of materials science and microfabrication processes, energy harvesters have become sophisticated, achieving power outputs in the range of several milliwatts, and have become a promising alternative to conventional batteries. Although their output power is insufficient to continuously operate a wireless sensor module, energy harvesters can operate small integrated circuits, including timers, watches, and ring oscillators. In this study, we emulated the human sensory nervous system to develop a battery-less sensor with a built-in analog-to-digital converter. The human sensory nervous system comprises a sophisticated sensing mechanism that digitalizes external stimuli by pulse-density modulation. To mimic this behavior, we integrated a ring oscillator with photovoltaics, allowing it to function as a luminance sensor with an event-driven operation. The oscillation frequency of the ring oscillator changes with respect to the operating voltage; hence, the output voltage of the photovoltaic modulates the frequency by more than two orders of magnitude. The sensor exhibits oscillation frequencies of 10 kHz and 7.7 MHz corresponding to luminance levels of 25–25 000 lx. Its response times are 40 μs and 15 ms when the light source is turned on and off, respectively. Battery-less sensors expand the opportunities for the application of energy harvesters in biomedical, wearable, and environmental sensing.
A new six-dimensional ab initio potential energy surface and rovibrational spectra for the N2–CO2 complex
Authors: Peng Yang , Jiang Xuedan , Liu Li , Liu Guangliang , Zhu Hua
Published: December 2023

New six-dimensional ab initio potential energy surfaces (PESs) for the N2–CO2 complex, which involve the stretching vibration of N2 and the Q3 normal mode for the ν3 asymmetric stretching vibration of CO2, were constructed using the CCSD(T)-F12/AVTZ method with midpoint bond functions. Two vibrational averaged 4D interaction potentials were obtained by integrating over the two intramolecular coordinates. It was found that both PESs possess two equivalent T-shaped global minima as well as two in-plane and one out-of-plane saddle points. Based on these PESs, rovibrational bound states and energy levels were calculated applying the radial discrete variable representation/angular finite basis representation method and the Lanczos algorithm. The splitting of the energy levels between oN2–CO2 and pN2–CO2 for the intermolecular vibrational ground state is determined to be only 0.000 09 cm−1 due to the higher barriers. The obtained band origin shift is about +0.471 74 cm−1 in the N2–CO2 infrared spectra with CO2 at the ν3 zone, which coincides with the experimental data of +0.483 74 cm−1. The frequencies of the in-plane geared-bending for N2–CO2 at the ν3 = 0 and 1 states of CO2 turn out to be 21.6152 and 21.4522 cm−1, the latter reproduces the available experimental 21.3793 cm−1 value with CO2 at the ν3 zone. The spectral parameters fitted from the rovibrational energy levels show that this dimer is a near prolate asymmetric rotor. The computed microwave transitions as well as the infrared fundamental and combination bands for the complex agree well with the observed data.
Absolute local conformation of poly(methyl methacrylate) chains adsorbed on a quartz surface
Authors: Kawaguchi Daisuke , Sasahara Kazuki , Inutsuka Manabu , Abe Tatsuki , Yamamoto Satoru , Tanaka Keiji
Published: December 2023

Polymer chains at a buried interface with an inorganic solid play a critical role in the performance of polymer nanocomposites and adhesives. Sum frequency generation (SFG) vibrational spectroscopy with a sub-nanometer depth resolution provides valuable information regarding the orientation angle of functional groups at interfaces. However, in the case of conventional SFG, since the signal intensity is proportional to the square of the second-order nonlinear optical susceptibility and thereby loses phase information, it cannot be unambiguously determined whether the functional groups face upward or downward. This problem can be solved by phase-sensitive SFG (ps-SFG). We here applied ps-SFG to poly(methyl methacrylate) (PMMA) chains in direct contact with a quartz surface, shedding light on the local conformation of chains adsorbed onto the solid surface. The measurements made it possible to determine the absolute orientation of the ester methyl groups of PMMA, which were oriented toward the quartz interface. Combining ps-SFG with all-atomistic molecular dynamics simulation, the distribution of the local conformation and the driving force are also discussed.
Ultraviolet-sensitive and power-efficient oxide phototransistor enabled by nanometer-scale thickness engineering of InZnO semiconductor and gate bias modulation
Authors: Zhang Xuan , Ju Eun Chong , Lee Jong Min , Park Sung Kyu , Cho Sung Woon
Published: December 2023

Amorphous oxide semiconductor photodetectors (PDs) are promising ultrasensitive and power-efficient ultraviolet (UV) PDs because they generate low dark current in the dark and exhibit high photoresponse under UV irradiation owing to their superior UV absorption and photocarrier transport characteristics. Herein, we demonstrate UV-sensitive and power-efficient oxide phototransistors through the nanometer-scale engineering of oxide semiconductors and appropriate modulation of gate bias conditions. The dark current and photocurrent of an oxide phototransistor exhibit a trade-off relationship in terms of the thickness of the oxide semiconductor film. Ultrathin InZnO is disadvantageous for fabricating UV-sensitive PDs because of its low photoresponse. In contrast, excessively thick InZnO is disadvantageous for fabricating power-efficient UV PDs owing to its high dark current. However, the InZnO film with an optimal film thickness of 8 nm can simultaneously provide the advantages of both ultrathin and excessively thick cases owing to its low intrinsic carrier concentration and sufficient UV absorption depth. Consequently, an InZnO phototransistor with high UV-sensing performance (Smax = 1.25 × 106), low-power operation capability (Idark = ∼10−13A), and excellent repeatability is realized by using an 8-nm-thick InZnO semiconductor and applying appropriate gate bias modulation (constant gate bias for maximized photosensitivity and temporal positive bias pulse for persistence photocurrent elimination).
Sensitivity factor analysis of seismic performance of seismically isolated girder bridges during the operation period
Authors: Chen Li , Dong Zhenhua , Wang Zuohu
Published: December 2023

The seismic performance of isolated girder bridges is accurately investigated and addressed by considering the theoretical foundation of seismic isolation, taking into account the operational period’s service state and changes in relevant performance indicators of vulnerable components. The analysis encompasses a comprehensive parameter analysis of seismic performance during the operational period, utilizing finite element analysis software, which involves comparing and analyzing structural deflections, deformation performance, and damage performance of seismically isolated girder bridges under varying parameters. The research findings indicate that, in terms of evaluating the damage state of the member, the displacement of the girder end of the main girder is primarily influenced by the interface friction coefficient of the isolation device, followed by the post-yield stiffness of the bearing. Conversely, abutment lateral stiffness has a relatively minor influence. Moreover, it is observed that the mechanical properties of the bearing (friction coefficient and post-yield stiffness) exert a significant impact on the structural seismic response. Therefore, more attention should be paid to the functional condition and the variation of mechanical performance parameters of the seismic isolation bearing during the operational phase.
A model for collagen secretion by intercompartmental continuities
Authors: Bunel Louis , Pincet Lancelot , Malhotra Vivek , Raote Ishier , Pincet Frédéric
Published: December 2023

Newly synthesized secretory proteins are exported from the endoplasmic reticulum (ER) at specialized subcompartments called exit sites (ERES). Cargoes like procollagen are too large for export by the standard COPII-coated vesicle of 60 nm average diameter. We have previously suggested that procollagen is transported from the ER to the next secretory organelle, the ER–Golgi intermediate compartment (ERGIC), in TANGO1-dependent interorganelle tunnels. In the theoretical model presented here, we suggest that intrinsically disordered domains of TANGO1 in the ER lumen induce an entropic contraction, which exerts a force that draws procollagen toward the ERES. Within this framework, molecular gradients of pH and/or HSP47 between the ER and ERGIC create a force in the order of tens of femto-Newtons. This force is substantial enough to propel procollagen from the ER at a speed of approximately 1 nm · s
−1
. This calculated speed and the quantities of collagen secreted are similar to its observed physiological secretion rate in fibroblasts, consistent with the proposal that ER export is the rate-limiting step for procollagen secretion. Hence, the mechanism we propose is theoretically adequate to explain how cells can utilize molecular gradients and export procollagens at a rate commensurate with physiological needs.
A simplicial epidemic model for COVID-19 spread analysis
Authors: Chen Yuzhou , Gel Yulia R. , Marathe Madhav V. , Poor H. Vincent
Published: December 2023

Networks allow us to describe a wide range of interaction phenomena that occur in complex systems arising in such diverse fields of knowledge as neuroscience, engineering, ecology, finance, and social sciences. Until very recently, the primary focus of network models and tools has been on describing the pairwise relationships between system entities. However, increasingly more studies indicate that polyadic or higher-order group relationships among multiple network entities may be the key toward better understanding of the intrinsic mechanisms behind the functionality of complex systems. Such group interactions can be, in turn, described in a holistic manner by simplicial complexes of graphs. Inspired by these recently emerging results on the utility of the simplicial geometry of complex networks for contagion propagation and armed with a large-scale synthetic social contact network (also known as a digital twin) of the population in the U.S. state of Virginia, in this paper, we aim to glean insights into the role of higher-order social interactions and the associated varying social group determinants on COVID-19 propagation and mitigation measures.
Genetic crosses within and between species of
Cryptosporidium
Authors: Shaw Sebastian , Cohn Ian S. , Baptista Rodrigo P. , Xia Guoqin , Melillo Bruno , Agyabeng-Dadzie Fiifi , Kissinger Jessica C. , Striepen Boris
Published: December 2023

Parasites and their hosts are engaged in reciprocal coevolution that balances competing mechanisms of virulence, resistance, and evasion. This often leads to host specificity, but genomic reassortment between different strains can enable parasites to jump host barriers and conquer new niches. In the apicomplexan parasite
Cryptosporidium
, genetic exchange has been hypothesized to play a prominent role in adaptation to humans. The sexual lifecycle of the parasite provides a potential mechanism for such exchange; however, the boundaries of
Cryptosporidium
sex are currently undefined. To explore this experimentally, we established a model for genetic crosses. Drug resistance was engineered using a mutated phenylalanyl tRNA synthetase gene and marking strains with this and the previously used Neo transgene enabled selection of recombinant progeny. This is highly efficient, and genomic recombination is evident and can be continuously monitored in real time by drug resistance, flow cytometry, and PCR mapping. Using this approach, multiple loci can now be modified with ease. We demonstrate that essential genes can be ablated by crossing a Cre recombinase driver strain with floxed strains. We further find that genetic crosses are also feasible between species. Crossing
Cryptosporidium parvum,
a parasite of cattle and humans, and
Cryptosporidium tyzzeri
a mouse parasite resulted in progeny with a recombinant genome derived from both species that continues to vigorously replicate sexually. These experiments have important fundamental and translational implications for the evolution of
Cryptosporidium
and open the door to reverse- and forward-genetic analysis of parasite biology and host specificity.
The quantum house of cards
Authors: Waintal Xavier
Published: December 2023

Quantum computers have been proposed to solve a number of important problems such as discovering new drugs, new catalysts for fertilizer production, breaking encryption protocols, optimizing financial portfolios, or implementing new artificial intelligence applications. Yet, to date, a simple task such as multiplying 3 by 5 is beyond existing quantum hardware. This article examines the difficulties that would need to be solved for quantum computers to live up to their promises. I discuss the whole stack of technologies that has been envisioned to build a quantum computer from the top layers (the actual algorithms and associated applications) down to the very bottom ones (the quantum hardware, its control electronics, cryogeny, etc.) while not forgetting the crucial intermediate layer of quantum error correction.
Protective human antibodies against a conserved epitope in pre- and postfusion influenza hemagglutinin
Authors: Finney Joel , Moseman Annie Park , Kong Susan , Watanabe Akiko , Song Shengli , Walsh Richard M. , Kuraoka Masayuki , Kotaki Ryutaro , Moseman E. Ashley , McCarthy Kevin R. , Liao Dongmei , Liang Xiaoe , Nie Xiaoyan , Lavidor Olivia , Abbott Richard , Harrison Stephen C. , Kelsoe Garnett
Published: December 2023

Phylogenetically and antigenically distinct influenza A and B viruses (IAV and IBV) circulate in human populations, causing widespread morbidity. Antibodies (Abs) that bind epitopes conserved in both IAV and IBV hemagglutinins (HAs) could protect against disease by diverse virus subtypes. Only one reported HA Ab, isolated from a combinatorial display library, protects against both IAV and IBV. Thus, there has been so far no information on the likelihood of finding naturally occurring human Abs that bind HAs of diverse IAV subtypes and IBV lineages. We have now recovered from several unrelated human donors five clonal Abs that bind a conserved epitope preferentially exposed in the postfusion conformation of IAV and IVB HA2. These Abs lack neutralizing activity in vitro but in mice provide strong, IgG subtype–dependent protection against lethal IAV and IBV infections. Strategies to elicit similar Abs routinely might contribute to more effective influenza vaccines.
Basal forebrain cholinergic activity is necessary for upward firing rate homeostasis in the rodent visual cortex
Authors: Bottorff Juliet , Padgett Sydney , Turrigiano Gina G.
Published: December 2023

Bidirectional homeostatic plasticity allows neurons and circuits to maintain stable firing in the face of developmental or learning-induced perturbations. In the primary visual cortex (V1), upward firing rate homeostasis (FRH) only occurs during active wake (AW) and downward during sleep, but how this behavioral state-dependent gating is accomplished is unknown. Here, we focus on how AW enables upward FRH in V1 of juvenile Long Evans rats. A major difference between quiet wake (QW), when upward FRH is absent, and AW, when it is present, is increased cholinergic (ACh) tone, and the main cholinergic projections to V1 arise from the horizontal diagonal band of the basal forebrain (HDB ACh). We therefore chemogenetically inhibited HDB ACh neurons while inducing upward homeostatic compensation using direct activity-suppression in V1. We found that synaptic scaling up and intrinsic homeostatic plasticity, two important cellular mediators of upward FRH, were both impaired when HDB ACh neurons were inhibited. Most strikingly, HDB ACh inhibition flipped the sign of intrinsic plasticity so that it became anti-homeostatic, and this effect was phenocopied by knockdown of the M1 ACh receptor in V1, indicating that this modulation of intrinsic plasticity is the result of direct actions of ACh within V1. Finally, we found that upward FRH induced by visual deprivation was completely prevented by HDB ACh inhibition. Together, our results show that HDB ACh modulation is a key enabler of upward homeostatic plasticity and FRH, and more broadly suggest that neuromodulatory inputs can segregate upward and downward homeostatic plasticity into distinct behavioral states.
A Confined Two-peaked Solar Flare Observed by EAST and SDO
Authors: Zhang Liang , Zheng Ruisheng , Xue Zhike , Rao Changhui , Lin Qing , Du Zhimao , Yao Jiawen , Zhong Libo , Chen Yao
Published: December 2023

The solar flare is one of the most violent explosions, and can disturb the near-Earth space weather. Except for commonly single-peaked solar flares in soft X-ray, some special flares show intriguing a two-peak feature that is deserved much more attentions. Here, we reported a confined two-peaked solar flare and analyzed the associated eruptions using high-quality observations from Educational Adaptive-optics Solar Telescope and Solar Dynamics Observatory. Before the flare, a magnetic flux rope (MFR) formed through partially tether-cutting reconnection between two sheared arches. The flare occurred after the MFR eruption that was confined by the overlying strong field. Interestingly, a small underlying filament immediately erupted, which was possibly destabilized by the flare ribbon. The successive eruptions were confirmed by the analysis of the emission measure and the reconnection fluxes. Therefore, we suggest that the two peaks of the confined solar flare are corresponding to two episodes of magnetic reconnection during the successive eruptions of the MFR and the underlying filament.
Theoretical and experimental analysis of the impact of a recuperative stage on the performance of an ORC-based solar microcogeneration unit
Authors: Fatigati Fabio , Coletta Arianna , Carapellucci Roberto , Cipollone Roberto
Published: December 2023

Microgeneration ORC-based units driven by solar energy, which enable combined heat and power generation (CHP), are a promising solution for decarbonizing the domestic sector. However, the intermittent availability of solar energy, coupled with the variability in user demand for domestic hot water (DHW), can lead the system to frequent off-design conditions and a less reliable energy supply. Consequently, increasing attention has recently been focused on the technological and design solutions for improving plant performance and ensuring its continuous operation. This paper presents the results of an experimental campaign carried out to investigate the possible advantages – in terms of efficiency and savings of thermal energy in the upper source – of introducing a recovery heat exchanger (RHX) in the basic configuration of a solar ORC-based system. Tests were conducted on a fully instrumented ORC-based plant with two 12 kW electric heaters providing the thermal power recovered through the solar collectors. The RHX is introduced into a recuperative branch that can be bypassed by closing a dedicated three-way valve. The study aims to investigate the behavior of the ORC unit in the absence of solar radiation (with the electric heaters switched off) when the recovery unit is powered only by the hot water stored in the Thermal Energy Storage (TES) tank. Another purpose of the present work is to evaluate the benefits introduced by the RHX in reducing the temperature decrease of the TES hot water and, consequently, maximizing the operating time of the ORC-based unit. In order to support the experimental analysis, a comprehensive theoretical model of the unit was developed and validated against experimental data. The model was used as a software platform to optimize the plant design and recuperative branch configuration. The theoretical model was developed in the GT-Suite™ environment thus integrating a mono and zero-thermo-fluid-dynamic approach. In this way, a physical representation of the entire ORC-based unit is performed allowing also to define an optimal control strategy for maximizing plant performance under severe off-design and transient conditions.
Renewable energy community design and evaluation according to the Italian regulation
Authors: Brumana G. , Franchini G. , Ghirardi E. , Caldera M.
Published: December 2023

The target of a Renewable Energy Community (REC) is to improve the renewable energy consumption without forcing the grid to work as a power backup and avoid the installation of large energy storage systems. The paper proposes a comparison between different REC configurations with the same annual energy consumption of 500 MWh corresponding to about 200 residential houses in northern Italy. The comparison includes different kinds of building destination (residential, commercial, industrial), and different photovoltaic (PV) installed capacity. The results highlight the fundamental role of a proper design of the Renewable Energy Community configuration. RECs based on members with complementary loads enhance the renewable energy consumption by increasing the fraction of shared energy. Different roles (consumer and prosumer) are fundamental to provide the proper energy distribution during the sunny hours by producing a win-win condition. Nevertheless, an increase of the PV capacity can produce a detrimental effect on the shared energy ratio due the non-contemporaneity of production and consumption.