bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on the design rainstorm calculation for the watershed in northern area of Xiamen New Airport
Authors: Deng Dejun , Huang Yanghua , You Shufeng , Li Shengcai , Liu Yanmin , Chi Changjia , Huang Siqi , Liu Sijia
Published: February 2024

Urban design rainstorm is the basis of urban hydraulic engineering design, which is related to the safety and economy of urban drainage engineering, and has an important impact on the design scale and investment of urban drainage engineering. Scientific design rainstorm is the basis for ensuring the construction of hydraulic engineering.To ensure the safety of the new airport, government restarts the hydraulic engineering in the northern area of Dadeng Airport. This paper takes the northern area of Xiamen New Airport as the research object, and provides an effective pursuant for hydraulic engineering design through scientific design rainstorm ,and also provides a reference for other similar construction projects.
Time Cost Optimization of Assembly Building Installation Phase Based on Particle Swarm Optimization
Authors: Chen Xiaoyu , Shou Kai
Published: February 2024

This paper combines the theory of resource-constrained project scheduling to analyze the cost influencing factors during the installation phase of prefabricated buildings, and establishes a resource-constrained scheduling model with the goal of minimizing the installation time to achieve the optimization of time cost during the installation phase.
Research on the design concept of three-dimensional ecological building
Authors: Sun Yutong , Sun Haibo , Dong Yu
Published: February 2024

This chapter highlights the significance of three-dimensional ecological architecture as a crucial direction for the development of green architecture in China. The design concept is centered around four main principles: green, energy-saving, user-friendly, and ecological circulation. This case analysis demonstrates the effectiveness of incorporating ecological elements and sustainable design strategies into building structures, resulting in reduced energy consumption, improved indoor environmental quality, and enhanced biodiversity. The chapter explores the development trends and insights derived from one case study, providing valuable references for China future advancement of green architecture.
Study of the industrial potential of Markforged X7 3D printer
Authors: Nikiema Daouda , Sergent Alain , Balland Pascale
Published: February 2024

Additive Manufacturing (AM) using Fused Deposition Modelling (FDM) is a 3D printing technique that can produce parts with complex shapes. Multiple types of 3D printers are available in the market, so it is essential to understand their potential to manufacture parts that meet industry standards. This study aims to evaluate the industrial potential of the Markforged X7 printer by assessing its performance based on the QS9000 quality standard. The quality indices, including the Cp index and the Cpk index, were determined for different dimensions, and admissible tolerances were identified for geometrical defects. The study shows that the quality indices, especially the Cp index, are within an acceptable range of 1.6 to 2 for the class 12 tolerance interval (IT12). The geometrical defects are predominantly categorized as fine according to the ISO 2768 standard, with deviations in geometrical features ranging from 0.06 to 0.08 mm. Additionally, the study investigated the impact of moisture and glass fiber reinforcement on the geometrical features. The analysis indicated that moisture increases deviations in the features. However, adding reinforcing fibers does not improve deviations but stabilizes them under the effect of moisture.
Randomisierte doppelblinde Studie zur Vorhersage der Notwendigkeit einer Nierenersatztherapie mittels Furosemid-Stress-Test
Authors: Artunc Ferruh
Published: February 2024

Das akute Nierenversagen (ANV) ist eine häufige Komplikation auf der Intensivstation und erfordert oft die Einleitung einer Nierenersatztherapie, meist in Form einer Hämodialyse. Zur Klärung der Frage nach dem idealen Zeitpunkt der Dialyseeinleitung existieren einige randomisierte kontrollierte Studien, die eine frühe Strategie basierend auf dem Erreichen der Stadien II und III des ANV im Vergleich zu den klassischen Dialyseindikationen wie Anurie oder nicht konservativ zu beherrschende Hyperkaliämie, Azidose oder Hypervolämie untersuchten.
Diuretika bei arterieller Hypertonie
Authors: Essigke Daniel
Published: February 2024

Seit Jahrzehnten sind Diuretika bei der antihypertensiven Therapie nicht wegzudenken und werden millionenfach verordnet. In den letzten Jahren wurden verschiedentliche Studien publiziert, in denen der Stellenwert von Diuretika in der antihypertensiven Therapie untersucht worden ist. Daraufhin wurde die Bedeutung von Diuretika in den zuletzt publizierten Hypertonieleitlinien großer Fachgesellschaften betont, was in der Folge auch zu Zulassungserweiterungen führen könnte. Nach der Veröffentlichung einer dänischen Studie bestanden zwischenzeitlich Unsicherheiten hinsichtlich des mit der Einnahme von Hydrochlorothiazid verbundenen Risikos für Hauttumoren. Diese konnten mittlerweile besser eingeordnet werden, sodass Patienten weiterhin von der Therapie profitieren können. Beim Blick in die Zukunft darf man gespannt auf die neuen Entwicklungen insbesondere in Bezug auf die neuen nichtsteroidalen Mineralokortikoid-Rezeptor-Antagonisten (MRA) und ihren Beitrag zur antihypertensiven Therapie sein.
Magen-Darm-Erkrankungen mit Heil- und Vitalpilzen erfolgreich
therapieren
Authors: Ogroske Dorothee
Published: February 2024

Ungesunde Ernährung, ein hektischer, stressreicher Lebensstil, emotionale Belastungen, Bewegungsmangel
sowie die Einnahme bestimmter Medikamente haben einen negativen Einfluss auf unsere
Magen-Darm-Gesundheit. Völlegefühl, Blähungen, Reizdarm, Sodbrennen, Durchfälle oder auch anhaltende
Verstopfung sind weit verbreitete Symptome, die die Lebensqualität der Betroffenen erheblich
beeinträchtigen, insbesondere wenn sie sich chronifizieren. Darüber hinaus leiden viele Menschen in den
modernen Gesellschaften unter schwerwiegenden Magen-Darm-Erkrankungen wie Morbus Crohn oder Colitis
ulcerosa. Der Gesundheitszustand unseres Verdauungstraktes hat auch einen großen Einfluss auf unsere
Gesamtgesundheit. Mit den in der Mykotherapie eingesetzten Vitalpilzen – sie werden synonym auch Heil-
bzw. medizinisch wirksame Pilze genannt – steht eine effektive naturheilkundliche Therapieoption zur
Verfügung. So leisten Vitalpilze einen wertvollen Beitrag zur Wiederherstellung und Erhaltung der Magen-
und Darmgesundheit und einer intakten Verdauung. Ihr Einsatz hat sich bei der Behandlung einer Vielzahl
von Magen-Darm-Erkrankungen bewährt.
Darmnosoden im täglichen Gebrauch
Authors: Wittwer Heinz
Published: February 2024

Darmnosoden sind wertvolle Heilmittel, die bisher nicht den Bekanntheitsgrad erlangt haben, der ihnen
gebührt. Wie die Nosoden oder die Muttermittel stammen sie aus dem Humanreich und haben deshalb – korrekt
verschrieben – oft eine erstaunlich gute Wirkung. Darmnosoden sind ein wichtiger Bestandteil der
homöopathischen Therapie und werden zur Behandlung von Darmbeschwerden und anderen Erkrankungen
eingesetzt. Sie werden aus krankhaften Geweben oder Sekreten des Darmes hergestellt und in potenzierter
Form verabreicht, um das Immunsystem zu stimulieren und die Selbstheilungskräfte des Körpers zu
aktivieren. In der Homöopathie werden Darmnosoden als eine Möglichkeit betrachtet, um die Gesundheit des
Verdauungssystems zu unterstützen und gleichzeitig das Gleichgewicht des gesamten Organismus
wiederherzustellen. Der Beitrag stellt die großen und kleinen Darmnosoden vor und zeigt
Anwendungsbeispiele aus und für die Praxis.
Impact of Pachychoroid and DRIL on the Treatment of Diabetic Macular Oedema with Intravitreal Bevacizumab
Authors: Gabriel Sara , Aljundi Wissam , Munteanu Cristian , Weinstein Isabel , Seitz Berthold , Abdin Alaa Din
Published: February 2024

Purpose To evaluate the long-term outcome of intravitreal bevacizumab in eyes with diabetic macular oedema (DME) following a PRN (pro re nata) regimen. Additionally, we investigated
the effect of the presence of disorganisation of the retinal inner layers (DRILs) and pachychoroid (PC) at baseline on clinical outcome.

Methods This retrospective study included 112 naïve eyes with DME that were followed up for 2 years. All eyes were treated with six initial bevacizumab injections at monthly
intervals and then received treatment according to a PRN regimen. In case of poor response to bevacizumab, therapy was switched to other agents. Main outcome measures included:
best-corrected visual acuity (BCVA), central macular thickness (CMT), and number of intravitreal injections (IVI s). In addition, we examined the effect of the presence of DRILs and PC at
baseline on clinical outcome.

Results BVCA improved significantly and CMT decreased significantly during the first 2 years of treatment. The number of IVI s per eye was 11.1 ± 4.8 at the end of the second year.
Treatment had to be switched to other agents in 47 eyes (42%). The timing of switching was 12.4 ± 6.1 months after a mean of 9.2 ± 3.3 IVI s. Patients with DRILs at baseline (29.5%) had
significantly worse BCVA at all time points before and after treatment, although CMT was significantly lower before treatment and comparable to patients without DRILs during treatment.
Patients with PC at baseline (35.7%) had no significant differences in BVCA and CMT at all time points compared with patients without PC.

Conclusions This study demonstrates statistically significant functional and anatomical improvement in patients with DME treated with intravitreal bevacizumab after 2 years. However,
more than 40% of eyes required a switch in therapy. The presence of DRILs at baseline had a negative effect whereas the presence of PC at baseline had no effect on clinical outcome.
Development, evaluation, and overview of standardized training phantoms for abdominal ultrasound-guided interventions
Authors: Blank Valentin , Karlas Thomas , Seitzinger Max , Gnatzy Franziska , Kern Sabine , Steinhausen Ralf , Klammer Jana , Schlosser Tobias
Published: February 2024

Purpose Ultrasound (US) represents the primary approach for abdominal diagnosis and is regularly used to guide diagnostic and therapeutic interventions (INVUS). Due to possible serious INVUS complications, structured training concepts are required. Phantoms can facilitate teaching, but their use is currently restricted by complex manufacturing and short durability of the materials. Hence, the aim of this study was the development and evaluation of an optimized abdominal INVUS phantom.

Materials and Methods Phantom requirements were defined in a structured research process: Skin-like surface texture, homogeneous matrix with realistic tissue properties, implementation of lesions and abscess cavities in different sizes and depths as well as a modular production process allowing for customized layouts. The phantom prototypes were evaluated in certified ultrasound courses.

Results In accordance with the defined specifications, a new type of matrix was developed and cast in multiple layers including different target materials. The phantom structure is based on features of liver anatomy and includes solid focal lesions, vessels, and abscess formations. For a realistic biopsy procedure, ultrasound-proof material was additionally included to imitate bone. The evaluation was performed by US novices (n=40) and experienced participants (n=41). The majority (73/81) confirmed realistic visualization of the lesions. The 3D impression was rated as “very good” in 64% of cases (52/81) and good in 31% (25/81). Overall, 86% (70/81) of the participants certified high clinical relevance of the phantom.

Conclusion The presented INVUS phantom concept allows standardized and realistic training for interventions.
Elevated Levels of Interleukin-18 are Associated with Lymph Node
Metastasis in Papillary Thyroid Carcinoma
Authors: Chun Wang , Lu Meiyin , Chen Jiakang , Li Jian
Published: February 2024

Interleukin-18 (IL-18) is a proinflammatory cytokine that primarily stimulates
the Th1 immune response. IL-18 exhibits anticancer activity and has been
evaluated in clinical trials as a potential cancer treatment. However, evidence
suggests that it may also facilitate the development and progression of some
cancers. So far, the impact of IL-18 on papillary thyroid cancer (PTC) has not
been investigated. In this study, we found that the expression of IL-18 was
significantly increased in PTC compared to normal thyroid tissue. Elevated IL-18
expression was closely associated with lymphovascular invasion and lymph node
metastases. Furthermore, compared to PTC patients with no nodal metastasis,
serum IL-18 levels were slightly increased in patients with 1–4 nodal
metastases and significantly elevated in patients with 5 or more nodal
metastases. The pro-metastatic effect of IL-18 may be attributed to the
simultaneous increase in the expression of S100A10, a known factor that is
linked to nodal metastasis in PTC. In addition, the activation of several
pathways, such as the intestinal immune network for lgA production and
Staphylococcus aureus infection, may be involved in the metastasis process.
Taken together, IL-18 may trigger pro-metastatic activity in PTC. Therefore,
suppressing the function of IL-18 rather than enhancing it appears to be a
reasonable strategy for treating aggressive PTC.
Acute Paraplegia Caused by Spinal Epidural Empyema Following Infectious Cellulitis of the Hand: Case Report and Literature Review
Authors: Nery Breno , Filho Cláudio Brandão , Nunes Lucas , Quaggio Eduardo , Filho Fred Bernardes , Neto Joaquim Alencar , Melo Layssa Rhossana , Oliveira Anna Carolyne , Rabello Rafael , Durand Victoria Rodrigues , Silva Rayssa Rocha , Costa Rafael Emmanuel , Segundo José Alencar
Published: February 2024

Background Spinal epidural abscess is a rare but serious condition that can cause spinal cord compression and neurological deficits.

Case Description and Methods The article reports a case of a 31-year-old patient who presented with an infectious cellulitis in the left hand, which progressed to a spinal epidural abscess. The diagnosis was confirmed by clinical examination and magnetic resonance imaging. Treatment involved laminectomy, after which the patient had complete recovery of neurological deficits. This article is a case report with a literature review. Patient data and images were collected by the researchers who participated in the patient's care. The literature was reviewed by one of the researchers based on the search for articles in the PubMed database. For the research, the following keywords were inserted: “Spinal epidural empyema,” “Spinal epidural abscess.”

Conclusion Spinal epidural abscess is often underdiagnosed, which can lead to delays in treatment and serious complications. The relationship between cellulitis and spinal epidural abscess may be related to the spread of infection through the lymphatic or blood system.
Maternal Hemodynamics from Preconception to Delivery: Research and Potential Diagnostic and Therapeutic Implications: Position Statement by Italian Association of Preeclampsia and Italian Society of Perinatal Medicine
Authors: Vasapollo Barbara , Zullino Sara , Novelli Gian Paolo , Farsetti Daniele , Ottanelli Serena , Clemenza Sara , Micaglio Massimo , Ferrazzi Enrico , Di Martino Daniela Denis , Ghi Tullio , Di Pasquo Elvira , Orabona Rossana , Corbella Paola , Frigo Maria Grazia , Prefumo Federico , Stampalija Tamara , Giannubilo Stefano Raffaele , Valensise Herbert , Mecacci Federico
Published: February 2024

Objective The Italian Association of Preeclampsia (AIPE) and the Italian Society of Perinatal Medicine (SIMP) developed clinical questions on maternal hemodynamics state of the art.

Study Design AIPE and SIMP experts were divided in small groups and were invited to propose an overview of the existing literature on specific topics related to the clinical questions proposed, developing, wherever possible, clinical and/or research recommendations based on available evidence, expert opinion, and clinical importance. Draft recommendations with a clinical rationale were submitted to 8th AIPE and SIMP Consensus Expert Panel for consideration and approval, with at least 75% agreement required for individual recommendations to be included in the final version.

Results More and more evidence in literature underlines the relationship between maternal and fetal hemodynamics, as well as the relationship between maternal cardiovascular profile and fetal-maternal adverse outcomes such as fetal growth restriction and hypertensive disorders of pregnancy. Experts agreed on proposing a classification of pregnancy hypertension, complications, and cardiovascular states based on three different hemodynamic profiles depending on total peripheral vascular resistance values: hypodynamic (>1,300 dynes·s·cm−5), normo-dynamic, and hyperdynamic (<800 dynes·s·cm−5) circulation. This differentiation implies different therapeutical strategies, based drugs' characteristics, and maternal cardiovascular profile. Finally, the cardiovascular characteristics of the women may be useful for a rational approach to an appropriate follow-up, due to the increased cardiovascular risk later in life.

Conclusion Although the evidence might not be conclusive, given the lack of large randomized trials, maternal hemodynamics might have great importance in helping clinicians in understanding the pathophysiology and chose a rational treatment of patients with or at risk for pregnancy complications.

Key Points
Convenient Synthesis of Hexa- and Pentasaccharide Repeating Units Corresponding to the O-Polysaccharides of Acinetobacter baumannii O7 and Acinetobacter baumannii O10 Strains
Authors: Misra Anup Kumar , Sahaji Samim , Bag Puja
Published: February 2024

The synthesis of the hexa- and pentasaccharide repeating units of the cell wall O-polysaccharides of Acinetobacter baumannii O7 and O10 strains, respectively, has been achieved in very good yield using [4+2] and [4+1] block glycosylation strategies. The p-methoxybenzyl (PMB) group was used as an in situ removable protecting group, which was removed after glycosylation in the same pot by tuning the reaction condition. A challenging β-l-rhamnopyranosyl linkage was constructed using ‘armed-disarmed glycosylation’ conditions by the influence of a remotely located, H-bond mediating, picolinoyl group in the glycosyl donor. A d-mannosamine intermediate was prepared from d-glucose using minimum reaction steps. The hexa- and pentasaccharide were achieved as their p-methoxyphenyl (PMP) glycosides.
Regioselective Aldehyde Decarbonylation through Palladium-Catalyzed Nitrile Boronic Acid Cross-Coupling
Authors: Raj Monika , Paikin Zachary E. , Talbott John M.
Published: February 2024

Aldehyde decarbonylation is a vital chemical transformation in the synthesis of natural products. Nature accomplishes this process through a family of decarbonylase enzymes, while in the laboratory, harsh transition metals and elevated temperatures are required. Herein, we report a mild aldehyde decarbonylation reaction that exhibits exclusive selectivity for ortho-aldehydes during a tandem nitrile boronic acid cross-coupling reaction. A wide substrate scope is displayed that includes regioselective removal of the ortho-aldehyde from phenyl boronic acids in the presence of meta- or para-aldehydes. A mechanistic investigation of the observed regioselectivity for ortho-aldehydes by density functional theory (DFT) calculations shows that the CO ligand extrusion is energetically more favorable for the ortho position as compared to the para position.
Public Versus Private Health Financing Transition in Low- and Middle-Income Countries: Exploring the Crowding-Out Effects
Authors: Behera Deepak Kumar , Rahut Dil B. , Haridas Herosh T. , Tasneem Shaik Husna
Published: February 2024

Healthcare financing is crucial for sustainable development and has been gaining attention, particularly since the COVID-19 pandemic. Although ample studies have explored the determinants of healthcare spending, the current study examines the determinants of health financing transition in 124 low- and middle-income countries (LMICs) for 19 years, from 2000 to 2018. The study first estimates the elasticity of health expenditure (i.e., government, private, and external) to per capita income, fiscal spending, age dependency, control of corruption, and time; second, it investigates crowding-out/in effects between domestic and external health financing. As the sample countries are heterogeneous in terms of development and universal health coverage (UHC) reform, our study employs a panel regression model with cluster-robust fixed effects and a bootstrapping quantile regression with fixed effects model to capture unobserved heterogeneity and produce robust estimates across quantile distributions. The results show that an increase in per capita government health expenditure (GHE) and per capita external health expenditure from foreign donors can reduce the share of out-of-pocket health expenditure to total health expenditure (OOPHE), thereby improving the health status and well-being of the people. The study also finds crowding-out effects of per capita external health financing on GHE in LIMCs. Interestingly, the results show that the control of corruption increases the per capita GHE in low-income countries. Thus, in low-income countries, improving governance would improve efficiency in fund utilization and strengthen the health system. Further, our study concludes that those countries that have passed UHC legislation are moving faster toward health financing transition by increasing public spending on health care. Healthcare policy in developing countries should prioritize (i) the adoption and implementation of UHC reform, (ii) alternative revenue mobilization strategy for financing public health care.
From wages for housework to self-care: feminist perspectives on the care economy
Authors: Moser Anna
Published: February 2024

This article argues that privatization of health care since the 1970s has created a paradox whereby a neoliberal discourse of ‘freedom of choice’ masks the fact that it is increasingly difficult to make good choices when it comes to caring for oneself and for one’s loved ones. Part one historicizes this paradox by examining the pioneering international feminist movement Wages for Housework. I argue that Wages for Housework offered a glimpse of a counter-model of state-renumerated care through its revolutionary demand that all houseworkers receive a government wage. At the same time, I call attention to limitations of the movement. Building on the insights of this case study, part two contends that the privatization and commodification of care – especially in the US and the UK in recent years—is fundamentally linked to the ‘responsibilization’ of female-identified subjects. To demonstrate this, I turn to the issue of self-care, arguing that the emergence of self-care as a lucrative twenty-first century market is an important consequence and indicator of this responsibilization. Specifically, I show how individual choice is recast as a societal obligation to assume a consumerist standpoint of ‘self-investment’ that, in itself, becomes a necessary precondition of the ‘right’ choice. I conclude by asserting that it is unjust to frame care—whether for oneself or for others—as a problem of individual responsibility and explore proposals for a ‘universal basic services’ model as the most equitable solution to the current care crisis.
Low-power MoS2 metal–semiconductor field effect transistors (MESFETs) based on standard metal–semiconductor contact
Authors: Yang Chengzhi , Jiang Cheng , Niu Wencheng , Hao Dandan , Huang Hao , Fu Houqiang , Miao Jinshui , Liu Xingqiang , Zou Xuming , Shan Fukai , Yang Zhenyu
Published: February 2024

With the popularization of electronic devices and the demand for portability, low-power consumption has become crucial for integrated circuit chips. Two-dimensional (2D) semiconductors offer significant potential in constructing low-power devices due to their ultrathin thickness, enabling fully depletion operation. However, fabricating these 2D low-power devices, such as negative-capacitance transistors or tunneling transistors, often requires multiple layers of gate dielectrics or channel band engineering, adding complexity to the manufacturing process and posing challenges for their integration with silicon technology. In this work, we have developed low-power MoS2 metal–semiconductor field effect transistors utilizing a standard metal–semiconductor contact, which eliminates the need for gate dielectrics and semiconductor heterojunctions. It demonstrates a sharp subthreshold slope (SS ∼ 64 mV/dec), a minimum operating gate voltage range (−0.5 ∼ 1 V), a minimum current hysteresis (3.69 mV), and a stable threshold voltage close to 0 V (Vth ∼ −0.27 V). Moreover, we implemented an inverter circuit with a high voltage gain of 47.
Effect of nonthermal electron distributions on dust acoustic solitons in cometary plasmas
Authors: Zaidi S. A. M. , Qureshi M. N. S. , Khalid Saba
Published: February 2024

We investigate the effect of nonthermal electrons modeled by two non-Maxwellian distribution functions, i.e., the (r, q) and Cairn’s distributions on the formation of dust acoustic (DA) solitons in an un-magnetized dusty plasma by incorporating the effect of dust streaming. We adopt the pseudopotential technique to obtain solitary wave solutions from fluid equations. It is seen that only rarefactive soliton can be obtained in such plasmas where ions are considered Boltzmannian and electrons non-Maxwellian. We find that soliton characteristics are strongly dependent on the nonthermal spectral indices r, q, and α and dust temperature Td. For (r, q) distribution, it is found that soliton amplitude increases but width decreases when the positive (negative) value of r decreases (increases). For Cairn’s distribution, we find that with the increase in α, soliton amplitude decreases. In space environments, such as cometary tails, solar wind, and Earth’s magnetosphere, where non-Maxwellian populations of electrons are present, our theoretical results show that the amplitude of soliton remains smaller than the Maxwellian case. Thus, Maxwellian distribution overestimates the soliton amplitude in such space environments. Therefore, we feel that our results will better interpret the results of observations, from cometary tails, and other space plasmas where nonlinear DA structures are likely to be observed.
Combining extrapolated electron localization functions and Berlin’s binding functions for the prediction of dissociative electron attachment
Authors: Titeca Charlotte , Jagau Thomas-C. , De Proft Frank
Published: February 2024

Computational study of electronic resonances is still a very challenging topic, with the phenomenon of dissociative electron attachment (DEA) being one of the multiple features worth investigating. Recently, we extended the charge stabilization method from energies to properties of conceptual density functional theory and applied this to metastable anionic states of ethene and chlorinated ethene derivatives to study the DEA mechanism present in these compounds. We now present an extension to spatial functions, namely, the electronic Fukui function and the electron localization function. The results of our analysis show that extrapolated spatial functions are relevant and useful for more precise localization of the unbound electron. Furthermore, we report for the first time the combination of the electron localization function with Berlin’s binding function for these challenging electronic states. This promising methodology allows for accurate predictions of when and where DEA will happen in the molecules studied and provides more insight into the process.
Guanidinium lead iodide two-dimensional perovskite single crystal for efficient x-ray detection
Authors: Zhang Ludi , Qian Chong-Xin , Lu Shan-Shan , Feng Hong-Jian
Published: February 2024

The recently reported two-dimensional lead halide perovskites have attracted much attention in high-energy radiation detector applications due to its high structural stability and low ion migration. However, the increased exciton binding energy and the charge transport barrier resulting from the A-site cation can easily limit the charge extraction and device performance. As an emerging material in high-energy detection field, guanidinium {GA+ = [C(NH2)3]+} is a relatively large organic cation composed of three amino groups, which can enhance the hydrogen bond formation and the van der Waals interactions with the metal halide framework. Meanwhile, the polymer symmetry of GA+ cation leads to almost zero dipole moments, excellent electronic properties, and high thermodynamic stability. However, there is a lack of report on the preparation, structure, and properties of GA-based 2D perovskite single crystals as well as their applications in x-ray detection. Herein, we have synthesized large-size two-dimensional GA2PbI4 single crystals with a bandgap of 2.28 eV by cooling crystallization and applied them to x-ray detectors. GA2PbI4 single crystals exhibit a high μτ product of 7.5 × 10−4 cm2 V−1 and a low trap density of 6.44 × 108 cm−3. An effective x-ray photoresponse was realized with a sensitivity as high as 392.4 μC Gyair−1 cm−2. The unique structure and excellent charge transport properties of GA+ organic cations exhibit promising prospects in high-performance x-ray detection.
Holographic nanodiamond–polymer composite grating with unprecedented slow-neutron refractive index modulation amplitude
Authors: Hadden Elhoucine , Fally Martin , Iso Yuko , Jenke Tobias , Klepp Jürgen , Kume Atsushi , Umemoto Koichi , Tomita Yasuo
Published: February 2024

We demonstrate exceptionally high slow-neutron diffraction efficiency (≈ 70% of transmitted intensity diffracted to the first order) from a holographic nanodiamond–polymer composite grating of only tens of micrometers thickness at the average neutron wavelength of 5.3 nm. By meticulous choice of materials for extreme refractive index modulation in a thin grating structure, we overcome typical wavelength and angular selectivity issues usually encountered when pursuing high diffraction efficiencies with a thick grating. This achievement paves the way for the implementation of flux-efficient diffractive elements, well-suited for polychromatic beams, and weakly collimated slow-neutron beams.
Parallel computational ghost imaging with modulation patterns multiplexing and permutation inspired by compound eyes
Authors: Ma Mengchao , Shen Yinran , Zha Peiyuan , Guan Qingtian , Zhong Xiang , Deng Huaxia , Zhang Xuming , Wang Ziwei
Published: February 2024

Real-time computational ghost imaging (CGI) has received significant attention in recent years to overcome the trade-off between long acquisition time and high reconstructed image quality of CGI. Inspired by compound eyes, we propose a parallel computational ghost imaging with modulation patterns multiplexing and permutation to achieve a faster and high-resolution CGI. With modulation patterns multiplexing and permutation, several small overlapping fields-of-view can be obtained; meanwhile, the difficulty in alignment of illumination light field and multiple detectors can be well resolved. The method combining compound eyes with multi-detectors to capture light intensity can resolve the issue of a gap between detector units in the array detector. Parallel computation facilitates significantly reduced acquisition time, while maintaining reconstructed quality without compromising the sampling ratio. Experiments indicate that using m × m detectors reduce modulation pattern count, projector storage, and projection time to around 1/m2 of typical CGI methods, while increasing image resolution to m2 times. This work greatly promotes the practicability of parallel computational ghost imaging and provides optional solution for real-time computational ghost imaging.
The effect of damping on the vortex-induced vibration of a rectangular prism
Authors: Tang Zhaolie , Zou Guang , Li Linsheng
Published: February 2024

In this work, the vortex-induced vibration of a rectangular prism with a side ratio of 4 is numerically investigated using a two-dimensional spectral-element method for several structural damping. The prism is constrained to vibrate only in the cross-flow direction. The vibration is governed by an impinging leading-edge vortex instability, while the trailing-edge vortex between two leading-edge vortices also contributes to the amplitude. The results show that increasing the damping reduces not only the displacement amplitude but also the range of lock-in. It is found that the phase difference between the lift force and motion plays an important role that is related to the added mass. After suppressing the trailing-edge vortex using a splitter plate, the vibration amplitude varies almost linearly with the phase difference. In addition, the essence of the lock-in reduction is that there is a critical phase difference above which lock-in disappears for a certain reduced velocity and the critical phase difference changes linearly with the reduced velocity. A new semi-empirical model based on the phase difference is proposed to predict the vibration amplitude and lock-in regime under different damping values. Rectangular prism experiments with two different side ratios are used to verify the effectiveness of the model.
Investigation of laser plasma instabilities driven by 527 nm laser pulses relevant for direct drive inertial confinement fusion
Authors: Wasser F. , Zähter Ş. , Rivers M. , Atzeni S. , Condamine F. P. , Cristoforetti G. , Fauvel G. , Fischer N. , Gizzi L. A. , Hoffmann D. , Koester P. , Laštovička T. , Myatt J. F. , Singh R. L. , Sokol M. , Theobald W. , Weber S. , Ditmire T. , Forner T. , Roth M.
Published: February 2024

We report on a study of laser plasma instabilities with 527 nm laser pulses in an intensity range of 0.5×1013−1.1×1015 Wcm−2 and plasma parameters entering a regime that is relevant for direct drive inertial confinement fusion. Using the kilojoule high repetition rate L4n laser at the Extreme Light Infrastructure—Beamlines, more than 1300 shots were collected, and the onset and the growth of stimulated Brioullin scattering (SBS) and stimulated Raman scattering (SRS) were studied with a high confidence level. The measured onset intensities are 0.2×1014 Wcm−2 for SBS and 1.4×1014 Wcm−2 for SRS. At the maximum intensity, the total fraction of backscattered energy reaches 2.5% for SBS and 0.1% for SRS. These results are of high relevance for advanced concepts for inertial fusion energy, which rely on the use of 527 nm laser light to drive the implosion of the fuel target, and in particular, they can be used as a benchmark for advanced simulations.
Quantum dynamics of excited state proton transfer in green fluorescent protein
Authors: Bourne-Worster Susannah , Worth Graham A.
Published: February 2024

Photoexcitation of green fluorescent protein (GFP) triggers long-range proton transfer along a “wire” of neighboring protein residues, which, in turn, activates its characteristic green fluorescence. The GFP proton wire is one of the simplest, most well-characterized models of biological proton transfer but remains challenging to simulate due to the sensitivity of its energetics to the surrounding protein conformation and the possibility of non-classical behavior associated with the movement of lightweight protons. Using a direct dynamics variational multiconfigurational Gaussian wavepacket method to provide a fully quantum description of both electrons and nuclei, we explore the mechanism of excited state proton transfer in a high-dimensional model of the GFP chromophore cluster over the first two picoseconds following excitation. During our simulation, we observe the sequential starts of two of the three proton transfers along the wire, confirming the predictions of previous studies that the overall process starts from the end of the wire furthest from the fluorescent chromophore and proceeds in a concerted but asynchronous manner. Furthermore, by comparing the full quantum dynamics to a set of classical trajectories, we provide unambiguous evidence that tunneling plays a critical role in facilitating the leading proton transfer.
Impact of the induced nematohydrodynamics over the Freedericksz transition limit
Authors: Lalitha Ramisetti , Mondal Sourav
Published: February 2024

Liquid crystals (LC) are highly sensitive to the external field. If any external (electric or magnetic) field is applied to the LC domain beyond a critical strength, the reorientation of the molecules takes place and attains a new equilibrated state, aligning to the direction of the applied external field, known as the Fréedericksz transition. This phenomenon is widely used for optical switching in display devices and dynamic field-induced optoelectronic applications. In this work, we investigate the role of induced (nemato-)hydrodynamics by the LC field reorganization on the dynamics of the LC alignment on account of the Fréedericksz transition. The three-dimensional nematic field dynamics is modeled using the Beris–Edwards framework, minimizing the Landau de-Genes free energy, and coupled to the associated fluid flow profile. Previous studies on the LC dynamics is based on the nematic relaxation alone without the impact of the hydrodynamics. This is a reasonable approximation in the limit of the high elastic (material) constant of the LC, but not true otherwise. The LC response is delayed with the increase in Ericksen number since the local flow effect significantly influence the dynamic behavior of the nematic field. The work results are helpful in understanding the role of hydrodynamics on the LC field transition and related to the optimal switching frequency of the electrical signals, which affect the refresh rate of the LC-based display systems.
Back-contact perovskite light-emitting diodes
Authors: Parkhomenko Hryhorii P. , Jumabekov Askhat N.
Published: February 2024

Light-emitting diodes utilizing halide perovskites have experienced rapid advancements in recent years, demonstrating notable external quantum efficiencies. Despite these strides, the practical implementation of such devices remains constrained. In this contribution, we are dedicated to developing perovskite light-emitting diodes with a back-contact architecture using the MAPbBr3 active layer and SnO2 and Ni/NiOx back electrodes. The quantum efficiency of the fabricated devices stands at 0.015%. The operational voltage of the light-emitting diodes is characterized by its pronounced low values, attaining a maximum luminance of 70 cd/m2 at a mere 3.2 V. These results demonstrate the considerable promise of the developed back-contact perovskite light-emitting diodes for prospective applications in advanced display technologies and light communication systems.
Extracting vector magnitudes of dominant structures in a cyclic engine flow with dimensionality reduction
Authors: Baker S. J. , Fang X. H. , Barbato A. , Breda S. , Magnani M. , Fontanesi S. , Leach F. C. P. , Davy M. H.
Published: February 2024

In fluid mechanics research, data gathered from measurements and simulations may be challenging to interpret due to complexities such as transience, non-linearity, and high dimensionality. Velocity data from the airflow through an internal combustion engine often exhibit such properties; nevertheless, accurate characterizations of these airflows are required in order to correctly predict and control the subsequent combustion and emission processes in pursuit of net zero targets. The temporal mean is a common way of representing an ensemble of realizations of velocity fields, but the averaging process can artificially diminish the magnitudes of the resultant vectors. Accurate representation of these vector magnitudes is of particular importance, as the velocity magnitudes in the intake airflow are thought to be primary drivers of the subsequent variation in an engine flow, which influences emission formation and overall efficiency. As an alternative to the ensemble mean, this work proposes the application of a dimensionality reduction method known as the sparsity-promoting dynamic mode decomposition (SPDMD), which can extract core structures from an ensemble of velocity fields while retaining more realistic vector magnitudes. This is demonstrated for the first time with large-eddy simulation (LES) velocity data and compared to a corresponding set of experimental particle image velocimetry (PIV) data. The SPDMD 0 Hz modes are shown to be more representative of the velocity magnitudes present in both datasets. This facilitates more accurate quantification of the differences in vector magnitudes between simulations and experiments, and more reliable identification of which LES snapshots are closer to the PIV ensemble.
Efficient periodic resolution-of-the-identity Hartree–Fock exchange method withk-point sampling and Gaussian basis sets
Authors: Bussy Augustin , Hutter Jürg
Published: February 2024

Simulations of condensed matter systems at the hybrid density functional theory level pose significant computational challenges. The elevated costs arise from the non-local nature of the Hartree–Fock exchange (HFX) in conjunction with the necessity to approach the thermodynamic limit. In this work, we address these issues with the development of a new efficient method for the calculation of HFX in periodic systems, employing k-point sampling. We rely on a local atom-specific resolution-of-the-identity scheme, the use of atom-centered Gaussian type orbitals, and the truncation of the Coulomb interaction to limit computational complexity. Our real-space approach exhibits a scaling that is, at worst, linear with the number of k-points. Issues related to basis set diffuseness are effectively addressed through the auxiliary density matrix method. We report the implementation in the CP2K software package, as well as accuracy and performance benchmarks. This method demonstrates excellent agreement with equivalent Γ-point supercell calculations in terms of relative energies and nuclear gradients. Good strong and weak scaling performances, as well as graphics processing unit (GPU) acceleration, make this implementation a promising candidate for high-performance computing.
A detour transition between thermal field emission and space charge limited regimes
Authors: Lin Chubin , Chen Jiandong , Fu Yangyang
Published: February 2024

Child–Langmuir law theoretically predicts the transition from thermionic electron emission to space charge limited (SCL) current density across a diode gap. In this work, we reveal a detour transition between thermal-field electron emission and SCL current regimes by tuning influential parameters. The effects of the cathode temperature T, local field enhancement factor β, and applied electric field E on the transition behaviors are evaluated based on particle-in-cell simulations. The transmitted current density dominated by either thermionic or field emission shows good agreement with the theoretical prediction whereas the deviations from the SCL current during the transition regions are captured. A backward absorption of emitted electrons is explicitly identified in the thermionic regime when the electric field is reversed. In addition, the boundaries corresponding to the SCL regimes are demonstrated with different combinations of the tuning parameters (T,β,E).
In-plane strain-induced structural phase transition and interlayer antiferromagnetic skyrmions in 2H-VSe2 bilayer
Authors: Guan Zhihao , Feng Dushuo , Xiao Runhu , Wu Xiaoping , Song Changsheng
Published: February 2024

The sliding and manipulation of interlayer magnetism and magnetic topological textures in two-dimensional (2D) layered materials have recently received tremendous attention. In this work, using first-principles calculations, we report a structural phase transition induced by manipulating the interlayer distance using an in-plane biaxial strain in a 2H-VSe2 bilayer. This structural phase transition is accompanied by a semiconductor-to-metal transition, in-plane-to-out-of-plane magnetization switching, and a reversal in the chirality of the Dzyaloshinskii–Moriya interaction (DMI). The binding strength of the interlayer Se2–Se3 atoms and charge density difference can serve as indicators for this structural phase transition. Furthermore, the interlayer distance of Se2–Se3 atoms can be employed as a descriptor that perfectly characterizes the degree of symmetry breaking and the magnitude of the DMI resulting from the broken spatial symmetry due to sliding. In addition, using atomistic simulations, we identify magnetic topological textures such as interlayer antiferromagnetic (AFM) frustrated bimerons and interlayer AFM skyrmions with strain. These results are beneficial for understanding and manipulating the interlayer properties of 2D layered materials through in-plane biaxial strain. In addition, the interlayer AFM frustrated bimerons and skyrmions in bilayer VSe2, which can suppress the skyrmion Hall effect due to the canceled Magnus forces in the top and bottom layers, highlight the promising applications of VSe2 in next-generation information storage devices.
Nonreciprocal charge-density-wave proximity effect in a lateral heterojunction of NbSe2/TiSe2
Authors: Akber Humaira , Shan Huan , Mao Yahui , Yao Jie , Zhai Xiaofang , Zhao Aidi
Published: February 2024

Lateral heterostructures between two-dimensional (2D) transition metal dichalcogenides are highly interesting since they have potential applications for constructing monolayer electronic devices. Such in-plane heterostructures are also ideal systems for exploring the interfacial effects on quantum phases, such as charge-density wave (CDW) order in the true 2D limit. Here, we report on a lateral CDW heterojunction made of monolayer NbSe2 and TiSe2 with atomically sharp interface. Scanning tunneling microscopy reveals an unexpectedly nonreciprocal CDW proximity effect at the NbSe2 vicinity of the heterojunctions: the (2 × 2) CDW order of TiSe2 is found to propagate into the NbSe2 side of the heterostructure, while the (3 × 3) CDW order of NbSe2 resides in the NbSe2 side. Such a nonreciprocal CDW proximity effect indicates that the quantum phase of electrons in NbSe2 can be easily tuned by the adjacent TiSe2. Our study highlights the significance of quantum interfacial effect in lateral heterojunctions, which may help for constructing tunable 2D in-plane quantum devices based on proximity effects or in-plane interfaces.
Impact of the thickness on the optical and electronic and structural properties of sputtered Cu2S thin films
Authors: Velasquez-Ordoñez J. R. , Rivera-Taco J. , Pacheco-Salazar D. G. , Coaquira J. A. H. , Maldonado J. L. , Guerra J. A. , Llontop P. , Morais P. C. , Aragón F. F. H.
Published: February 2024

A successful hexagonal Cu2S p-type semiconductor thin film using DC magnetron sputtering is reported. Films with thickness gradients were deposited by taking advantage of deposition geometry and target dimensions. X-ray diffraction (XRD) analysis confirmed the exclusive formation of the hexagonal Cu2S phase. Elemental composition and thickness dependence with the sample position were determined using energy-dispersive x-ray spectroscopy. Optical properties, including the optical bandgap, refractive index, and extinction coefficient, were assessed by modeling transmittance spectra. The Tauc–Lorentz oscillator and Drude models were employed for this purpose. XRD data analysis successfully determined the film thickness (tXRD) as a function of the sample position, aligning well with thickness values (tT) derived from transmittance spectra analyses. These results were further supported by film thickness values (tSEM) obtained from cross-sectional SEM images. Charge carrier density and mobility, extracted from the optical models, were found to be consistent with DC electrical measurements. AC impedance curves were effectively modeled with RL–RC parallel circuits. The results indicate that the inductance (L) and capacitance (C) components of the films increase with decreasing film thickness.