bluuebunny/crossref_metadata_2025 huggingface dataset:
Randomness assisted imaging
Authors: Singh Rakesh Kumar
Published: July 2024

Randomness in the light usually appears as a noise and obstacle in the optical imaging. Nevertheless, these random patterns can be used to design and develop new and un-conventional imaging methods. In this paper, we dis-cuss and highlight potential of randomness assisted imaging.
Plasmonic rectification effect in an asymmetric periodically gated graphene field effect transistor for THz detection
Authors: Tang Chao , Seki Hironobu , Tamura Koichi , Uchigasaki Shinnosuke , Fukidome Hirokazu , Takida Yuma , Minamide Hiroaki , Satou Akira , Otsuji Taiichi
Published: July 2024

In this study, we propose a novel approach to THz wave detection using an asymmetrically gated graphene field-effect transistor (GFET). By utilizing two sets of gates arranged in an asymmetric manner, we achieve periodic modulation of the carrier density along the channel. Previous re-search has explored various mechanisms for THz detection, including the photothermalelectric (PTE) effect, photovoltaic (PV) effect, bolometric (BM) effect, and plasma rectification (PR) [1]. While PR [2] has been observed in a direct-current photoresponse [3], but yet to be in fast temporal response. Our study aims to provide direct evidence of PR-based fast-speed detection in a GFET. We apply a specific bias to the asymmetrically gated GFET, resulting in a periodically arranged carrier density and observing clear evidence of PR in the graphene channel.
Remote charge modulation effect of monolayer MoS2 using periodically polarization-inverted structure and hBN spacer layer
Authors: Rong Kaipeng , Noro Ryosuke , Nishigaki Hayato , Ding Mingda , Yao Yao , Inoue Taiki , Katayama Ryuji , Kobayashi Yoshihiro , Matsuda Kazunari , Mouri Shinichiro
Published: July 2024

Molybdenum disulfide (MoS2) is a typical two-dimensional layered material that exhibits unique properties offering opportunities for the development of nanoelectronics, valleytronics, and spintronics. Exploring the way to modulate carrier distribution is an important issue for controlling these device performance [1]. Here we demonstrate the “remote” spatial carrier modulation method for MoS2 using periodically polarization inversed ferroelectric structure and spacer h-BN layers. We transferred exfoliated few layers hBN and monolayer MoS2 flake sequentially onto a periodically polarization-inverted structure formed on a ferroelectric substrate MgO: LiNbO3. The schematic cross-sectional image of the sample was shown in upper of Fig.1. Photoluminescence (PL) mapping measurement was carried to investigate the distribution of charge density of monolayer MoS2. Lower of Fig. 1 shows the PL mapping image of this sample, expressing the intensity ratio of trion peak (IT, ~1.84eV) and exciton peak (IX, ~1.88 eV), which changes according to the charge density. It clearly shows that the exciton weight of monolayer MoS2 changes spatially, depending on the polarization of substrate. We also plot the IT/IX value in Fig.1(b) along the line shown in Fig 1 (a). It shows that the value of IT/IX approximately equals 0.5 and 2 relatively on down- and up-domain.
Observation of quantum coherence of a single moiré exciton in nano-fabricated twisted MoSe2/WSe2 heterobilayers
Authors: Wang Haonan , Kim Heejun , Dong Duanfei , Shinokita Keisuke , Watanabe Kenji , Taniguchi Takashi , Matsuda Kazunari
Published: July 2024

Recently, rapid progress on artificial van der Waals (vdW) structures by stacking atomically thin two-dimensional materials has opened up new opportunities for the design of novel quantum systems [1]. Three-dimensional confinement provided by the periodic ordered potential traps not only makes moiré system promising for achieving long coherence time [2], but also suitable for exploring interaction between systems. However, broad emissions attributed to ensemble-averaged multiple peaks caused by inhomogeneity of the moiré potentials hinder the detail exploration of quantum coherence and interference of the moiré system.
Direct imaging of valley-polarized excitons in 2D semiconductors
Authors: Bacon David R. , Zhu Xing , Pareek Vivek , Watanabe Kenji , Taniguchi Takashi , Man Michael K. L. , Madéo Julien , Dani Keshav M.
Published: July 2024

The monolayer transition-metal dichalcogenides (TMDCs), lacking inversion symmetry, allow the manipulation of excitonic states with valley degree of freedom through circularly polarized light [1-3]. However, with the complex landscape of exciton species in TMDCs, such as spin- or momentum- forbidden dark excitons, the valley depolarization mechanisms, which are of great importance for valleytronic applications, still lack clear understanding. Such measurements require direct access to the momentum and energy coordinate of constituent electrons and holes, but few experimental techniques provide such information. Meanwhile, time- and angle- resolved photoemission spectroscopy (TR-ARPES) has become a powerful tool to study excitons of 2D semiconductors in energy-momentum space [4-7]. In this talk, we focus on our momentum-resolved study on the valley-polarized excitons in monolayer WS2
Synthesis of wafer-scaled single-crystal 2D layered materials via chemical vapor deposition
Authors: Kim Ki Kang
Published: July 2024

Two-dimensional (2D) materials including graphene, hexagonal boron nitride, and transition metal dichalcogenide have been paid attentions due to unusual intrinsic physical and chemical properties such as high exciton binding energy and large magnetic resistance. Such unusual properties allow unprecedented applications. To realize the intrinsic material properties and industrial applications, wafer-scaled single-crystal 2D films are highly required. Here, I present the recent progress of single-crystal growth for 2D van der Waals materials in a wafer scale via the self-collimation on liquid substrate and the epitaxial growth on self- atomic sawtooth surface. The detailed growth mechanism is discussed accordingly.
Pd Decoration at Vertical Edge of MoS2 for Enhanced NO2 Sensitivity: A DFT Study
Authors: Kushwaha Aditya , Goel Neeraj
Published: July 2024

Gas sensors are vital for safety, air quality monitoring, industrial enhancement, and emission compliance [1]. NO2, a harmful gas released from the burning of fossil fuels, poses health hazards and contributes to pollution. Decorating noble metals on 2D transition metal dichalcogenide (TMD) nanomaterial-based gas sensors provides benefits like enhanced sensitivity, selectivity, fast response, and so on [2]. In this work, density functional theory (DFT) study compared NO2 sensing in pristine MoS2, Pd decorated at basal plane of MoS2 (Pd-B-MoS2), and Pd decorated at vertical edge of MoS2 (Pd-V-MoS2). Pd nanoparticles (NPs) decoration (top site) induce catalytic oxidation by extracting electrons from MoS2 through Fermi level disparities [3]. NO2, an electron-repelling compound, withdraws electrons from Pd-NPs. The spillover effect in Pd-V-MoS2 amplifies its sensing capabilities by offering additional reactive Mo sites [4]. Pd-V-MoS2 showed higher NO2 sensitivity than MoS2 and Pd-B-MoS2.
Nonlinear Optical Response of Jahn-Teller Susceptible Mixed Transition Metal Oxide
Authors: Sharma Ankit , Pathak Mansi , Rout C.S , Adarsh K.V.
Published: July 2024

The sustainability of optical nonlinearities of material systems is crucial for future technological and fundamental importance e.g., optical switching, signal processing, second harmonic generation, solar energy harvesting, optical limiting, frequency-comb, etc. In the last four decades, extensive works had been dedicated to advances in the nonlinear optics field but still, we rely on metal chalcogenides, LiNbO3, BBO, etc. as a nonlinear crystal for technological applications. However, several groups have demonstrated different materials systems with relatively enhanced optical nonlinearities and their prospects, e.g., 2D TMDCs, vertical and horizontal heterostructures, and inorganic and organic perovskites. But they are still in the struggling stage for device applications due to their low growth yield, and high instability. Here, we have chosen mixed transition metal oxides MnCo2O4 and demonstrated its nonlinear optical response. Mostly, oxides are known for higher stability and wide bandgap materials and consequently, they are transparent for the visible and infrared regime. But the oxides from mixed transition metals with partially filled d-orbital provide an additional degree of freedom to exploit their oxides in the visible regime. Partial d-orbital of transition metals with tetrahedral/octahedral goes through structural distortion and stabilized the system energetically by splitting the conduction band into low and high-spin states. We exploit these properties and observed two optically active bands in optical absorption spectroscopy at ~ 768 nm and ~ 507 nm. Further, we investigated its third-order susceptibility by incorporating the open (OA) and close (CA) aperture standard Z-scan technique. We used 7 ns, 532 nm Gaussian shape laser excitation at 53 MW/cm2 and observed the valley at a tight focusing position with two shoulder peaks near the focus which is evidence of excited state absorption. Interestingly, the CA transmittance profile revealed the Kerr lensing effect i.e., self-focusing properties of MnCo2O4 under similar excitation. Finally, our study proposed another material system that can be a potential candidate for optics and photonics applications and therefore needs to be investigated extensively for the fundamental understanding of these emerging materials.
Nonlinear Coherent Light-matter Interaction: Promising all-Optical Switching, Logic Gate and Optical Limiting Applications
Authors: Nayak Sudhanshu Kumar , Ahmed Md Soif , Barman Chinmay , Murali Rahul , Bhavani Bota , Prasanthkumar Seelam , Giribabu Lingamallu , Raavi Sai Santosh Kumar
Published: July 2024

Spatial self-phase modulation (SSPM) is a nonlinear optical (NLO) coherent interaction between light and matters. The phase gets self-modulated due to the change of nonlinear refractive index through the nonlinear Kerr effect and produce diffraction rings at the far fields. [1] Porphyrins are the organic molecules with π-conjugation electron rich systems, they possess delocalized electric field distribution and large dipole moments that lead to have significant electrical polarization, which is a profit for higher NLO response. These molecules have various application in photovoltaics, photonics, optoelectronics, etc. [2, 3] Herein, we report the NLO properties of four metalated porphyrin-napthalimide based donor-acceptor systems named as PN-Zn, PN-Ni, PN-Cu, and PN-Fb using SSPM and continuous wave (CW) Z-scan method for exploring various optoelectronic applications like optical limiting, optical switching, and logic gates, etc.
Raman scattering on two-soliton interaction in silica and chalcogenide (As2Se3) optical fibers
Authors: Roy Abhisek , Chaudhuri Partha Roy
Published: July 2024

We study and explore the two-soliton interaction in silica and chalcogenide (As2Se3) fibers. For this, we focus on two temporally separated solitons in a single-mode fiber, revealing significant modification of Kerr-induced interaction by interpulse Raman scattering.
Versatile quantum state tomography of photonic states via Hong-Ou-Mandel interference
Authors: Tsujimoto Yoshiaki , Ikuta Rikizo , Wakui Kentaro , Kobayashi Toshiki , Fujiwara Mikio
Published: July 2024

Hong-Ou-Mandel (HOM) interference [1] is a bunching phenomenon based on the bosonic nature of photons. When two photons that are perfectly indistinguishable from each other are mixed using a half beam splitter (HBS), they always bunch and exhibit the absence of coincidence resulting in a specific interferogram called HOM dip. The important property of the HOM interference is that the decrease in coincidence reflects the degree of indistinguishability of the input photons, i.e., it provides information regarding the probability of overlap of the input photons. Thus, this property should enable the estimation of a target photon in an unknown quantum state using a probe photon in a known state. In this work, we realize the above concept as the quantum state tomography (QST) applicable to d-dimensional photonic qudits, which we call HOM-QST [2]. Interestingly, we observe that HOM-QST is robust against various imperfections and that the probe photon can be replaced by classical light. Furthermore, we confirm this by demonstrating a proof-of-principle experiment using two-dimensional polarization qubits.
Evaluation of Reflective Characteristics of Meta-atoms Employing Point Terahertz Sources and Its Application
Authors: Zheng Luwei , Hara Kazuki , Tonouchi Masayoshi , Serita Kazunori
Published: July 2024

THz technology has attracted considerable attention as a powerful sensing tool across a wide range of disciplines, including non-invasive/non-destructive detection, biology and material science1. Near-field technique2 with the capability of significantly enhancing the resolution and metamaterials technique3 with that of remarkably modulating electromagnetic wave properties has considerably facilitated its practical application in the THz band. In fact, we have successfully realized detection of solutes in solutions at the level of several hundred attomoles in picoliter volumes by measuring the resonance frequency shift. However, all results are carried out in transmission mode. And we believe that immense potential in terms of high resolution and high sensitivity features can be implemented in reflection mode.
Scintillation index evolution of chirped ring Pearcey vortex beam through atmospheric turbulence
Authors: Singh Shakti , Mishra Sanjay Kumar , Mishra Akhilesh Kumar
Published: July 2024

The research field of abruptly autofocusing (AAF) beam is witnessing a great surge of attention due to its unique properties such as self-healing, non-diffracting nature among others [1]. AAF beams with orbital angular momentum (OAM) [2] hold applications in free space optical communication (FSO) [3] due to its additional degree of freedom.
Refractive index measurement for plane parallel plate using fiber point diffraction lateral interference and numerical modeling
Authors: Zhao Zimo , Chen Lingfeng , Zhang Xusheng , Zhang Yang
Published: July 2024

A plane-parallel-plate (PPP) refractive index (RI) measurement method based on fiber point diffraction lateral interferometry and numerical modeling is proposed. Two fiber point light sources (PLSs) generate lateral interference through PPP, and the interferograms are collected by a linear array camera (LAC). Employing ray tracing of an ideal PLS and numerical simulation, the theoretical model of RI measurement is established by polynomial fitting with the RI of PPP as the output, the PPP thickness and the phase change at specific positions of the LAC detector as the inputs. To enhance measurement accuracy, the theoretical model is further corrected using PPP samples with known RI, measured thicknesses and phase changes. The experimental results indicate that the RI measurement accuracy can reach 10−4. Remarkably, this method features a simple structure and eliminates the intermediate optical components, except for the fiber PLSs, PPP samples, and LAC. We demonstrate how to simulate an ideal PLS with fiber PLSs and correct the numerical simulation model to improve the accuracy of RI measurement. Furthermore, this approach can be extended to other optical measurements.
Hollow Gaussian beam-based experimental investigation on echo measurements under atmospheric turbulence and central obstruction
Authors: Wang Jinhao , Li Ming , Han Xida , Tan Yuyang , Li Hui , Lin Xudong
Published: July 2024

Despite their potential, Cassegrain systems face challenges due to central obstruction, resulting in reduced emitting efficiency. Optical vortex (OV) beams, known for their unique orbital angular momentum (OAM) characteristics, show promise in enhancing transmission efficiency. However, the existence of central phase singularity in OV beams may limits their effectiveness in laser ranging. In this work, a solid 532 nm laser and a spatial light modulator (SLM) are used to produce the OV and hollow Gaussian beam (HGB). Per the requirements of our experiments, the transmission characteristics of OVs in the Fresnel region have been thoroughly investigated. Based on the healing properties of HGBs, Experimental validation is conducted using HGBs and OV beams under varying atmospheric turbulence levels, and stronger echo signals with HGBs are realized. Additionally, a simplified model simulating central obstruction challenges in Cassegrain systems is developed, HGB shows the superior performance of HGBs in improving transmission efficiency and enhancing echo signals. This research provides valuable insights for optimizing Cassegrain antenna systems and advancing laser ranging technology and highlighting the potential of HGBs as a promising solution for overcoming central obstruction challenges and improving overall system performance.
Oblique incidence of ultrafast laser for glass butt welding
Authors: Shen Hong , Tian Chenyun , Wei Xingyu
Published: July 2024

Lap welding restricts the connection state of glasses by vertically incident ultrafast laser at the interface to be welded, which cannot meet the increasingly flexible welding needs. In this Letter, glass butt welding is achieved by oblique incidence of an ultrafast laser, expanding the applicability of ultrafast laser glass welding. Furthermore, the propagation path of the laser beam after oblique incidence into a glass is solved based on geometric optics, the dynamic development of the molten pool in a glass is observed through a high-speed camera, and the mechanism of glass butt welding is elucidated. Finally, the influence of laser pulse energy, glass tilt angle, and defocus amount on welding strength is investigated, achieving a maximum shear strength of 11.5 MPa.
Observation of off-axis solitary waves propagating along a specific trajectory in photorefractive crystals
Authors: Quan Qingying , Lian Shengdi , Liu Zihan , Chen Hechong , Yan Bo , Deng Dongmei
Published: July 2024

We report the propagation dynamics of swallowtail beams (SBs) within a photorefractive crystal. In the nonlinear regime, the self-accelerating and secondary self-focusing features of the swallowtail beams are influenced, and a solitary wave is generated. The main lobe energy of the swallowtail beams is guided to a specific inclined trajectory, leading to a stable solitary wave, and we control the output position of the solitary wave by changing the launch angle. Our results are supported by the corresponding experiments. In addition, we demonstrate that a Gaussian beam can be effectively guided in swallowtail optical waveguide structures. Our research represents an interesting interaction between the swallowtail beams and nonlinear medium, which may find potential applications in photonic integrated devices and optical information transmission.
Strong coupling of an epsilon-near-zero mode to a chiral plasmon
Authors: Zhu Xiabing , Chen Shu , Xiao Ting-Hui
Published: July 2024

The reconfigurable chiroptical effect is highly desirable for spin photonics, chiral spectroscopy, and photocatalysis due to its merits for dynamic and broadband applications. The coupling of an epsilon-near-zero (ENZ) mode to a chiral plasmon is expected to enable active and effective manipulation of the chiroptical effect but remains unexplored. Here we, for the first time to our knowledge, propose and demonstrate the strong coupling of an ENZ mode to a chiral plasmon by using a hybrid system composed of two identical vertically placed gold nanorods and an in-between ENZ film. An analytical three-oscillator model combined with numerical simulations is established to study the coupling mechanism, which predicts a Rabi splitting up to 240 meV with an ENZ film thickness of 60 nm in circular dichroism.
Low-loss compact chalcogenide microresonators for efficient stimulated Brillouin lasers
Authors: Li Yufei , Xia Di , Cheng Huanjie , Luo Liyang , Wang Linyi , Zeng Siqing , Yang Shuixian , Li Linze , Chen Baile , Zhang Bin , Li Zhaohui
Published: July 2024

Chalcogenide glasses (ChGs) possess a high elasto-optic coefficient, making them ideal for applications in microwave photonics and narrow-linewidth lasers based on stimulated Brillouin scattering (SBS). However, current As2S3-based integrated devices suffer from poor stability and low laser-induced damage threshold, and planar ChG devices feature limited quality factors. In this Letter, we propose and demonstrate a high-quality integrated GeSbS ChG Brillouin photonic device. By introducing Euler bending structures, we suppress high-order optical modes and reduce propagation losses in a finger-shaped GeSbS microresonator, resulting in a compact footprint of 3.8 mm2 and a high intrinsic quality factor of 5.19 × 106. The combination of GeSbS material’s high Brillouin gain and the resonator’s high-quality factor enables the generation of stimulated Brillouin lasers with a low threshold of 0.96 mW and a fundamental linewidth of 58 Hz. Moreover, cascaded stimulated Brillouin lasers can be realized up to the seventh order, yielding microwave beat frequencies up to 40 GHz.
Spatial information allows inference of the prevalence of direct cell–to–cell viral infection
Authors: Williams Thomas , McCaw James M. , Osborne James M.
Published: July 2024

The role of direct cell–to–cell spread in viral infections—where virions spread between host and susceptible cells without needing to be secreted into the extracellular environment—has come to be understood as essential to the dynamics of medically significant viruses like hepatitis C and influenza. Recent work in both the experimental and mathematical modelling literature has attempted to quantify the prevalence of cell–to–cell infection compared to the conventional free virus route using a variety of methods and experimental data. However, estimates are subject to significant uncertainty and moreover rely on data collected by inhibiting one mode of infection by either chemical or physical factors, which may influence the other mode of infection to an extent which is difficult to quantify. In this work, we conduct a simulation–estimation study to probe the practical identifiability of the proportion of cell–to–cell infection, using two standard mathematical models and synthetic data that would likely be realistic to obtain in the laboratory. We show that this quantity cannot be estimated using non–spatial data alone, and that the collection of data which describes the spatial structure of the infection is necessary to infer the proportion of cell–to–cell infection. Our results provide guidance for the design of relevant experiments and mathematical tools for accurately inferring the prevalence of cell–to–cell infection in in vitro and in vivo contexts.
TAPS-tool reveals severe under detection of substance use problems in patients with severe mental illness
Authors: Seelen-de Lang Birgit , Jong Cor de , Hutschemaekers Giel , Didden Robert , Noorthoorn Eric
Published: July 2024

Introduction

Substance use disorders (SUD) and associated problems are highly prevalent but often undetected in patients with Severe Mental Illness (SMI). This study investigates the prevalence, under-detection, and variables associated with a high risk of SUD in a Dutch sample of adult outpatient SMI patients (N = 83).

Methods

Substance use (The Tobacco, Alcohol, Prescription medication, and other Substance use -TAPS-tool), quality of life (Manchester Short Assessment of Quality of Life—MANSA), general functioning (Health of the Nation Outcome Scale–HoNOS), DSM-5 classifications and patient characteristics (age, education, marital status) were assessed. Detection of SUD was determined by calculating % agreement of DSM-5 classification to TAPS outcome. A logistic regression analysis was performed to determine the association of patient characteristics, quality of life and general functioning to an increased risk of SUD as determined by the TAPS.

Results

Concerning prevalence, 89% of the patients used tobacco, above guideline-recommended daily limits of alcohol, illicit drugs or prescription medications for nonmedical purposes. Almost all smokers, half of the alcohol users and three-quarter of the patients that use marihuana or stimulant drugs had a high risk of SUD. All patients with high risk of SUD associated with alcohol, drugs or medications also had SUD associated with tobacco use. Concerning under detection less than half of the patients with a high risk of SUD according the TAPS had a SUD in their DSM-5 classification. Gender, partner, age and satisfaction about the relationship with family had a significant association with a high risk of SUD.

Conclusions

Screening for addiction in an SMI sample with the TAPS-tool revealed a high prevalence of substance use and a high risk of SUD. TAPS outcomes compared to the clinically obtained DSM-5 classification revealed a high degree of under-detection of substance use problems. Smoking seems to pose a specific additional risk of addiction and deserves more attention in treatment to achieve greater health care benefits.
Factors associated with homeless experiences amid the COVID-19 pandemic in the Nipissing District, Ontario, Canada
Authors: Odd Megan , Erfani Amir
Published: July 2024

Canadian homelessness is an ongoing issue, especially in the Nipissing District, Ontario, where agencies work to support those in need. However, these efforts were challenged with the sudden onset of the COVID-19 pandemic. Drawing on the Cycle of Homelessness model, this study examines sociodemographic factors associated with homeless experiences during the pandemic. Using data from the 2021 (n = 207) Nipissing District homeless enumeration survey and employing bivariate and multivariate binary logistic analyses, this study examined sociodemographic factors associated with reasons of homelessness, barriers to housing loss and experiences of chronic and episodic homelessness during the pandemic. The results showed a significant sociodemographic variation in the experiences of the homeless population during the COVID-19 pandemic. Those over the age of 35 versus their younger counterparts were more likely (43.7%) found in emergency shelters. Multivariate findings indicated that females experienced housing/financial loss and interpersonal/family issues, directly causing homelessness, 2.2 and 2.5 times more than males, respectively. Welfare recipients were more likely to experience health-related reasons for housing loss (Odds Ratio (OR): 2.8), chronic homelessness (OR: 3.3), addiction (OR: 2.9), and mental health-related barriers to housing (OR: 4.1). Those aged 25–34, 25–44, and 45+ were 7.9, 4.9, and 5.1 times more likely to face chronic homelessness.

Conclusions: Welfare recipients are more at-risk of health-related housing loss, addiction, and mental health barriers to housing, and chronic homelessness. This could be attributed to poor public planning and policies that put people in marginal economic and housing circumstances, especially during the pandemic. Therefore, policy reform is required to address the main barriers in eliminating homelessness.
A modified Tseng algorithm approach to restoring thoracic diseases’ computerized tomography images
Authors: Ozsahin Dilber Uzun , Adamu Abubakar , Aliyu Maryam Rabiu , Umar Huzaifa
Published: July 2024

It is well-known that the Tseng algorithm and its modifications have been successfully employed in approximating zeros of the sum of monotone operators. In this study, we restored various thoracic diseases’ computerized tomography (CT) images, which were degraded with a known blur function and additive noise, using a modified Tseng algorithm. The test images used in the study depict calcification of the Aorta, Subcutaneous Emphysema, Tortuous Aorta, Pneumomediastinum, and Pneumoperitoneum. Additionally, we employed well-known image restoration tools to enhance image quality and compared the quality of restored images with the originals. Finally, the study demonstrates the potential to advance monotone inclusion problem-solving, particularly in the field of medical image recovery.
Age and familiarity effects on musical memory
Authors: Sauvé Sarah A. , Satkunarajah Praveena , Cooke Stephen , Demirkaplan Özgen , Follett Alicia , Zendel Benjamin Rich
Published: July 2024

Background

A common complaint in older adults is trouble with their memory, especially for new information. Current knowledge about normal aging and changes in memory identify a divide between memory tasks that are unaffected by aging and those that are. Among the unaffected are recognition tasks. These memory tasks rely on accessing well-known information, often include environmental support, and tend to be automatic. Negative age effects on memory are often observed at both encoding and during recall. Older adults often have difficulty with recall tasks, particularly those that require effortful self-initiated processing, episodic memory, and retention of information about contextual cues. Research in memory for music in healthy aging suggests a skill-invariance hypothesis: that age effects dominate when general-purpose cognitive mechanisms are needed to perform the musical task at hand, while experience effects dominate when music-specific knowledge is needed to perform the task [1].

Aims

The goals of this pair of studies were to investigate the effects of age and familiarity on musical memory in the context of real pieces of music, and to compare a live concert experimental setting with a lab-based experimental setting.

Method

Participants’ task was to click a button (or press the spacebar) when they heard the target theme in three pieces of music. One was Mozart’s Eine Kleine Nachtmusik and the others were original pieces commissioned for this study, one tonal and one atonal. Participants heard the relevant theme three times before listening to a piece of music. The music was performed by the Newfoundland Symphony Orchestra; participants either attended the concert, or watched a recording of the concert in the lab. Participants also completed two short cognitive tests and filled out a questionnaire collecting demographic information and a hearing abilities self-assessment.

Results

We find a significant effect of familiarity and setting but not of age or musical training on recognition performance as measured by d’. More specifically, performance is best for the familiar, tonal piece, moderate for the unfamiliar tonal piece and worst for the unfamiliar atonal piece. Performance was better in the live setting than the lab setting.

Conclusions

The absence of an age effect provides encouraging evidence that music’s diverse cues may encourage cognitive scaffolding, in turn improving encoding and subsequent recognition. Better performance in an ecological versus lab setting supports the expansion of ecological studies in the field.
Quadruplex-duplex junction in LTR-III: A molecular insight into the complexes with BMH-21, namitecan and doxorubicin
Authors: Mazzini Stefania , Borgonovo Gigliola , Princiotto Salvatore , Artali Roberto , Musso Loana , Aviñó Anna , Eritja Ramon , Gargallo Raimundo , Dallavalle Sabrina
Published: July 2024

Quadruplex-Duplex (Q–D) junctions are unique structural motifs garnering increasing interest as drug targets, due to their frequent occurrence in genomic sequences. The viral HIV LTR-III sequence was chosen as a Q–D junction model to study the affinity of the selected compounds BMH-21, namitecan (ST-1968), and doxorubicin (DOXO), all containing a planar polycyclic aromatic moiety, linked to either one short aminoalkyl or an aminoglycosyl group. A multidisciplinary approach that combines NMR spectroscopy, molecular modelling, circular dichroism (CD) and fluorescence spectroscopy was employed. The studied ligands induced moderate but clear stabilization to the Q–D junction by interacting with the interfacial tetrad. DOXO was found to be the best Q–D junction binder. Interestingly, the removal of the aminoglycosyl group significantly changed the pattern of the interactions, indicating that highly polar substituents have a stronger affinity with the exposed regions of the Q–D junction, particularly at the level of the interfacial tetrad.
Unravelling the dynamics of child sexual exploitation material circulation on the Dark Web
Authors: Divakarmurthy Pramod , Requião da Cunha Bruno , Passold Jean Fernando , Oliveira Marcos , Menezes Ronaldo
Published: July 2024

In recent years, there has been a significant increase in the detection of child sexual exploitation material (CSEM), with perpetrators increasingly turning to advanced encryption technologies to conceal their activities. This study delves into data from a Brazilian Federal Police operation on the Tor network, aimed at disrupting these illicit activities. We uncovered patterns indicating strong user preferences for certain content categories, suggesting the existence of distinct groups with shared interests. Additionally, our findings reveal consistent activity patterns among users, including specific 24-hour, 12-hour, and 6-hour consumption cycles. This research offers insights into the online behavior related to CSEM, providing a foundation for further investigation and the development of effective policy measures.
Comparing healthcare systems between the Netherlands and Australia in management for children with acute gastroenteritis
Authors: Weghorst Anouk A. H. , Sanci Lena A. , Berger Marjolein Y. , Hiscock Harriet , Jansen Danielle E. M. C.
Published: July 2024

Background

Acute gastroenteritis is a highly contagious disease demanding effective public health and clinical care systems for prevention and early intervention to avoid outbreaks and symptom deterioration. The Netherlands and Australia are both top-performing, high-income countries where general practitioners (GPs) act as healthcare gatekeepers. However, there is a lower annual incidence and per-case costs for childhood gastroenteritis in Australia. Understanding the systems and policies in different countries can lead to improvements in processes and care. Therefore, we aimed to compare public health systems and clinical care for children with acute gastroenteritis in both countries.

Methods

A cross-country expert study was conducted for the Netherlands and Australia. Using the Health System Performance Assessment framework and discussions within the research group, two questionnaires (public health and clinical care) were developed. Questionnaires were delivered to local experts in the Netherlands and the state of Victoria, Australia. Data synthesis employed a narrative approach with constant comparison.

Results

In Australia, rotavirus vaccination is implemented in a national program with immunisation requirements and legislation for prevention, which is not the case in the Netherlands. Access to care differs, as Dutch children must visit their regular GP before the hospital, while in Australia, children have multiple options and can go directly to hospital. Funding varies, with the Netherlands providing fully funded healthcare for children, whilst in Australia it depends on which GP (co-payment required or not) and hospital (public or private) they visit. Additionally, the guideline-recommended dosage of the antiemetic ondansetron is lower in the Netherlands.

Conclusions

Healthcare approaches for managing childhood gastroenteritis differ between the Netherlands and Australia. The lower annual incidence and per-case costs for childhood gastroenteritis in Australia cannot solely be explained by the differences in healthcare system functions. Nevertheless, Australia’s robust public health system, characterized by legislation for vaccinations and quarantine, and the Netherland’s well-established clinical care system, featuring fully funded continuity of care and lower ondansetron dosages, offer opportunities for enhancing healthcare in both countries.
Microbiota composition effect on immunotherapy outcomes in colorectal cancer patients: A systematic review
Authors: Ajab Suad Mohamed , Zoughbor Sumaya Hasan , Labania Lena Abdulbaset , Östlundh Linda Mari , Orsud Hiba Salaheldin , Olanda Marie Antonette , Alkaabi Obaid , Alkuwaiti Shamma Hamad , Alnuaimi Shaikha Mohammed , Al Rasbi Zakeya
Published: July 2024

Background

Immune checkpoint inhibitors (ICIs) have emerged as an effective treatment for colorectal cancer (CRC). Studies indicate that the composition of gut microbiota could potentially serve as a biomarker for predicting the clinical effectiveness of immune checkpoint inhibitors.

Methods

Following PRISMA guidelines, the review was conducted after registering the protocol with PROSPERO. A comprehensive literature search was carried out across five databases: PubMed, Scopus, Web of Science, Embase, and Cochrane Library. Assessment tools from the National Institutes of Health (NIH) were used to gauge the quality of the studies

Results

A total of 5,132 papers were identified, and three studies and one conference abstract published between 2017–2022 met the inclusion criteria and were summarized in a descriptive synthesis table. These four studies were in accord with the following findings, four main phyla, Firmicutes, Bacteroidata, Actinobacteria, and Verrucomicrobiota were associated with CRC patients’ clinical response toward ICIs treatment. Ruminococcaceae was predominantly related to CRC patients responding to therapy, while the Micrococcaceae family was more common among the non-responders. Bacterial taxa such as Faecalibacterium and Prevotellaceae were associated with better responses to ICIs and could be predictive biomarkers. The signature of fecal microbiota with Akkermansia muciniphila and Eubacterium rectale enrichment, and Rothia mucilaginosa depletion could independently predict better response to ICIs in patients with CRC.

Conclusion

The findings have brought attention to the notable differences in terms of richness and composition of microbiota between patients who responded positively to the treatment and those who did not. Bacterial species and families, such as Faecalibacterium, Bifidobacterium, Lachnospiraceae, Akkermansia sp., Ruminococcaceae, and Prevotellaceae, have consistently surfaced as potential indicators of immunotherapeutic responses. Furthermore, this review also emphasizes the need for additional comprehensive, multi-center studies with larger sample sizes to validate reported microbiota and expand our understanding of the role of gut microbiota in CRC ICIs therapy.

PROSPERO ID: CRD42021277691
The association between alcohol consumption and herpes simplex virus type 2: A cross-sectional study from national health and nutrition examination survey 2009–2016
Authors: Shi Yushan , Zhang Jiafeng , Wang Zhantong , Shan Feng
Published: July 2024

Background

The current prevalence of Herpes simplex virus type 2 (HSV-2) infection is notably high, with individuals afflicted by HSV-2 facing recurrent outbreaks, challenges in achieving remission, and an elevated risk of HIV infection. This study aims to investigate the relationship between alcohol consumption and HSV-2 infection.

Methods

The data for this study were sourced from 7257 participants who took part in the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2016. The target population consisted of adults with reliable HSV-2 plasma results, and alcohol consumption was assessed using self-report methods. We evaluated the odds ratio (OR) and 95% confidence interval (CI) for the association between alcohol consumption and HSV-2 infection. These estimations were derived from a logistic regression model that was adjusted for key confounding factors. Subgroup analysis specifically focused on alcohol consumption, and the interaction between HSV-2 infection, alcohol consumption, and other variables was assessed through stratified analysis.

Results

Among the 7,257 participants included, 89.8% (6,518/7,257) reported varying levels of alcohol consumption history. Compared to individuals who never drinkers, the adjusted odds ratios (ORs) for former drinkers, light drinkers, moderate drinkers, and heavy drinkers were 1.79 (95% CI: 1.34–2.4, p < 0.001), 1.38 (95% CI: 1.07–1.77, p = 0.012), 1.49 (95% CI: 1.15–1.94, p = 0.003), and 1.47 (95% CI: 1.14–1.9, p = 0.003), respectively. The results remained stable in subgroup analyses and sensitivity analyses.

Conclusion

Current research indicates that individuals with a history of alcohol consumption exhibit a higher risk of HSV-2 infection compared to those who have never drinkers.
Molecular detection of toxoplasmosis in wild rats using loop-mediated isothermal amplification assay
Authors: Puspitasari Heni , Suwanti Lucia Tri , Mufasirin Mufasirin , Kusnoto Kusnoto , Yudaniayanti Ira Sari , Setiawan Boedi , Suprihati Endang , Aksono Eduardus Bimo , Widodo Dwi Priyo , Wardhana April Hari , Matsubayashi Makoto , Indasari Elly Nur
Published: July 2024

Background and Aim: Toxoplasmosis is caused by the parasite Toxoplasma gondii. Cats are the only known hosts that excrete resistant oocysts. Wild rats serve as crucial reservoirs and intermediate hosts for T. gondii’s survival and dissemination. Consuming soil and water containing oocysts can lead to illness. This study aimed to estimate the prevalence of toxoplasmosis in wild rats through molecular detection as an indicator of environmental contamination in Surabaya.

Materials and Methods: One hundred rats were collected from the three areas (housing, dense settlements, and traditional markets) and distributed into the five zones: West, East, Central, North, and South of Surabaya. Brain tissue samples were extracted using a Geneaid™ (New Taipei City, Taiwan) DNA isolation kit and analyzed through the loop-mediated isothermal amplification (LAMP) method.

Results: The study analyzed brain tissue from 100 wild rats, consisting of 77 Rattus tanezumi and 33 Rattus norvegicus, displaying 30% LAMP positivity. The study revealed that 30% (30/100) of wild rats tested were infected with T. gondii. The molecular prevalence rate in male rats was 32.35% (22/68), compared to females with 25% (8/32). 41.9% of the housing population, 33.3% of traditional markets, and 22.6% of dense settlements had the highest molecular prevalence. The high positive molecular rate at the trapping site can be attributed to cats and dense populations.

Conclusion: Thirty percentage wild rats were tested positive for toxoplasmosis in Surabaya, East Java, Indonesia using LAMP method. Implementing strict control and monitoring is crucial in preventing the transmission of diseases from wild rats to humans. It is necessary to carry out further research related to genetic analysis of T. gondii to determine the type of T. gondii that infects animals and humans in Surabaya through bioassay and molecular test.

Keywords: loop-mediated isothermal amplification, public health, tissue cyst, toxoplasmosis, wild rats.
Divergent DNA methylation patterns and gene expression in MYC and CDKN2B in canine transmissible venereal tumors
Authors: Keopaseuth Soukkangna , Pringproa Kidsadagon , Patchanee Prapas , Setthawongsin Chanokchon , Techangamsuwan Somporn , Chuammitri Phongsakorn
Published: July 2024

Background and Aim: Canine transmissible venereal tumor (CTVT), a unique transmissible cancer in dogs, affects the external genitalia and potentially spreads to other parts of the body. While somatic mutations in oncogenic and tumor-suppressing genes are linked to CTVT development, the impact of DNA methylation, which affects gene expression, remains unclear. This study explored whether DNA methylation in the promoter regions of the MYC oncogene and CDKN2B tumor suppressor genes in CTVTs is associated with their expression, both at the gene and protein levels.

Materials and Methods: To investigate promoter DNA methylation of MYC and CDKN2B in CTVTs, we analyzed frozen tissue samples from genital CTVT (GTVTs) and extragenital CTVT (ETVTs). Genomic DNA was extracted, bisulfite-treated, and analyzed using bisulfite polymerase chain reaction (PCR) and sequencing. The messenger RNA and protein of MYC and CDKN2B were also extracted and assessed by real-time PCR and Western blotting. Matching formalin-fixed, paraffin-embedded blocks were used for immunohistochemical staining to visualize protein distribution in GTVT and ETVT tissues.

Results: Although both GTVT and ETVT samples showed MYC promoter methylation, the extent of methylation differed significantly. GTVTs displayed a much higher degree of methylation, potentially explaining the more pronounced downregulation of MYC gene expression and reduction in c-MYC protein levels observed in GTVTs compared with ETVTs. Our data revealed a prevalent hypermethylation pattern in the CDKN2B promoter across both sample types. However, DNA methylation, which was expected to have a suppressive effect, did not correlate with gene/protein expression. GTVTs displayed high protein levels despite significantly reduced CDKN2B expression. Conversely, ETVTs maintained regular CDKN2B expression but exhibited reduced protein production, suggesting a complex interplay between methylation and expression in these tumors.

Conclusion: MYC demonstrated a clear association between its promoter methylation status, gene expression, and protein levels; however, CDKN2B lacked this correlation, implying the involvement of methylation-independent regulatory mechanisms and highlighting the need for further investigation.

Keywords: canine transmissible venereal tumor, CDKN2B, DNA methylation, MYC, oncogene, tumor suppressor gene.
Interesses políticos na evolução histórica do Direito Internacional dos Refugiados e no caso ucraniano: entre humanitarismo e seletividade na prática europeia
Authors: Jaeger Junior Augusto , Strauch Aveline Ricardo
Published: July 2024

O artigo analisa a influência dos interesses políticos sobre os processos de criação, interpretação e aplicação do Direito Internacional dos Refugiados, desde o período anterior à Convenção de Genebra de 1951 até a atualidade. Após a análise de momentos históricos relevantes, direciona-se o foco para o caso dos refugiados ucranianos e para a distinção no tratamento conferido a eles, em relação aos refugiados de outras regiões. Questiona-se se o caso ucraniano representaria a continuidade de um processo histórico marcado pela influência política sobre os processos de criação, interpretação e aplicação do Direito Internacional dos Refugiados. A pesquisa foi desenvolvida com a utilização de abordagem qualitativa e método dedutivo, com revisão bibliográfica, partindo de questões gerais para se chegar em conclusões particulares. Concluiu-se que, desde o período anterior à Convenção de Genebra de 1951, interesses políticos vêm exercendo papel central para a criação, interpretação e aplicação das normas sobre refúgio, assim como, para as práticas de acolhimento humanitário exercidas pelos Estados, conferindo-lhes um caráter seletivo, inclusive no caso ucraniano pós-invasão russa.
Sistem pembayaran QRIS sebagai upaya pengembangan UMKM di kota Ambon
Authors: Gainau Paskanova Christi , Engko Cecilia , Gaspersz Yesica Thelma
Published: July 2024

This study aims to examine the effect of using the QRIS payment system on MSME development in Ambon City through Theory of Acceptance Model. It uses the sample from all MSME culinary delights in Ambon City, taken based on the determined criteria such as meeting the criteria are 45 SMEs. The data were analyzed using multiple linear regression, which was processed by the SPSS version 21. The result shows that partially Perceived Usefulness and Perceived ease of use have a significant influence on the development of MSMEs in Ambon City. The more useful QRIS is, the more MSMEs will develop, as well as the easier it is to use QRIS, so it will be easy for business actors to adapt and their businesses will develop. It practically implies that MSMEs in Ambon City are getting more and more aware that the perceived usefulness and perceived ease of use available in the QRIS are able to encourage business development. Apart from that, Bank Indonesia as the promoter of QRIS implementation for MSMEs needs to monitor entrepreneurs using QRIS so that they can answer any obstacles they still face. Theoretically, it also implies that this research provides a new area of research not only limited to interest in using it but directly towards the application of new technology and its influence on the development of MSMEs.