bluuebunny/crossref_metadata_2025 huggingface dataset:
Inverse design of a grating metasurface for enhancing spontaneous emission through hyperbolic metamaterials
Authors: Ma Haoran , Bao Gang , Lai Jun , Lin Junshan
Published: January 2024

This work is concerned with inverse design of the grating metasurface over hyperbolic metamaterials (HMMs) in order to enhance spontaneous emission (SE). We formulate the design problem as a PDE-constrained optimization problem and employ the gradient descent method to solve the underlying optimization problem. The adjoint-state method is applied to compute the gradient of the objective function efficiently. Computational results show that the SE efficiency of the optical structure with the optimized metasurface increases by 600% in the near field compared to the bare HMM layer. In particular, an optimized double-slot metasurface obtained by this design method enhances the SE intensity by a factor of over 100 in the observation region.
Diode-pumped Tm:YAP laser operating at 2.3 µm with enhanced performance through cascade lasing
Authors: Yu Xiaoxu , Zha Fangyuan , Pan Zhongben , Chu Hongwei , Pan Han , Li Dechun
Published: January 2024

The laser diode (LD)-pumped Tm:YAP (
a
-cut, 3.5 at.%) laser generated a maximum ∼2.3 µm continuous wave (CW) laser output power of ∼3 W. The higher output power benefited from the positive effect of the cascade lasing (simultaneously operating on the 3H4 → 3H5 and 3F4 → 3H6 Tm3+ transition). It was the highest CW laser output power amongst the LD/Ti:Sapphire-CW-pumped ∼2.3 µm Tm3+-doped lasers reported so far. Under the cascade laser operation, the slope efficiency of the ∼2.3 µm laser emission versus the absorbed pump power increased from 13.0% to 21.4%.
Polychromatic and collimated lights generated by nondegenerate four-wave mixing in cesium vapor
Authors: Yang Baodong , Fan Jian , Xu Jing , Zheng Lanlan , Huang Wenyi , Zhou Haitao
Published: January 2024

We demonstrate the generation of polychromatic and collimated lights at 456 nm, 459 nm, and 761 nm based on cesium (133Cs) 6S1/2 - 6P3/2 - 8S1/2 - 7P3/2, 7P1/2, 6P1/2 - 6S1/2 multi-diamond-type atomic system via two-photon excitation with two IR pump lasers at 852 nm and 795 nm. The 456 nm, 459 nm (7P3/2, 7P1/2 → 6S1/2) collimated blue lights result from the self-seeded four-wave mixing process (FWM), and the 761 nm coherent light (8S1/2 → 6P1/2) is from a seeded FWM process with the injection of a third laser at 895 nm. We measure the dependency of generated polychromatic fields on the temperature of 133Cs vapor cell and the powers of input lasers, clearly demonstrating the competition between the self-seeded FWM and seeded FWM, as they share the same excitation path. This work is helpful to further produce entangled multi-color photons for quantum communication.
Depth estimation in SPAD-based LIDAR sensors
Authors: Chen Mingzhe , Rao Padmakumar R. , Venialgo Esteban
Published: January 2024

In direct time-of-flight (D-TOF) light detection and ranging (LIDAR), accuracy and full-scale range (FSR) are the main performance parameters to consider. Particularly, in single-photon avalanche diodes (SPAD) based systems, the photon-counting statistics plays a fundamental role in determining the LIDAR performance. Also, the intrinsic performance ultimately depends on the system parameters and constraints, which are set by the application. However, the best-achievable performance directly depends on the selected depth estimation method and is not necessarily equal to intrinsic performance. We evaluate a D-TOF LIDAR system, in the particular context of smartphone applications, in terms of parameter trade-offs and estimation efficiency. First, we develop a simulation model by combining radiometry and photon-counting statistics. Next, we perform a trade-off analysis to study dependencies between system parameters and application constraints, as well as non-linearities caused by the detection method. Further, we derive an analytical model to calculate the Cramér–Rao lower bound (CRLB) of the LIDAR system, which analytically accounts for the shot noise. Finally, we evaluate a depth estimation method based on artificial intelligence (AI) and compare its performance to the CRLB. We demonstrate that the AI-based estimator fully compensates the non-linearity in depth estimation, which varies depending on application conditions such as target reflectivity.
Multifocal multiview imaging and data compression based on angular–focal–spatial representation
Authors: Wu Kejun , Liu Qiong , Yap Kim-Hui , Yang You
Published: January 2024

Multifocal multiview (MFMV) is an emerging high-dimensional optical data that allows to record richer scene information but yields huge volumes of data. To unveil its imaging mechanism, we present an angular–focal–spatial representation model, which decomposes high-dimensional MFMV data into angular, spatial, and focal dimensions. To construct a comprehensive MFMV dataset, we leverage representative imaging prototypes, including digital camera imaging, emerging plenoptic refocusing, and synthesized Blender 3D creation. It is believed to be the first-of-its-kind MFMV dataset in multiple acquisition ways. To efficiently compress MFMV data, we propose the first, to our knowledge, MFMV data compression scheme based on angular–focal–spatial representation. It exploits inter-view, inter-stack, and intra-frame predictions to eliminate data redundancy in angular, focal, and spatial dimensions, respectively. Experiments demonstrate the proposed scheme outperforms the standard HEVC and MV-HEVC coding methods. As high as 3.693 dB PSNR gains and 64.22% bitrate savings can be achieved.
Continuous tuning of pulse parameters in a soliton fiber laser by adjusting the effect of nonlinear polarization rotation
Authors: Zhang Xintong , Guo Haozhe , He Wenbin , Wang Xiaocong , Huang Qi , Zheng Yu , Yin Ruochen , Huang Zhiyuan , Jiang Xin , Xu Lixin , Leng Yuxin , Pang Meng
Published: January 2024

We demonstrate that through inserting a short length of highly birefringent small-core photonic crystal fiber (Hi-Bi SC-PCF) into a soliton fiber laser, the nonlinear polarization rotation effect in this laser can be manipulated, leading to continuous tuning of the output pulse parameters. In experiments, we observed that by adjusting the polarization state of light launched into the Hi-Bi SC-PCF and varying the cavity attenuation, the laser spectral width can be continuously tuned from ∼7.1 to ∼1.7 nm, corresponding to a pulse-width-tuning range from ∼350 fs to ∼1.56 ps. During the parameter tuning, the output pulses strictly follow the soliton area theory, giving an almost constant time–bandwidth-product of ∼0.31. This soliton fiber laser, being capable of continuous parameter tuning, could be applied as the seed source in ultrafast laser systems and may find some applications in nonlinear-optics and soliton-dynamics experiments.
Quartz-enhanced photoacoustic spectroscopy sensing using trapezoidal- and round-head quartz tuning forks
Authors: Fang Chao , Liang Tiantian , Qiao Shunda , He Ying , Shen Zuochun , Ma Yufei
Published: January 2024

In this Letter, two novel, to the best of our knowledge, quartz tuning forks (QTFs) with trapezoidal-head and round-head were designed and adopted for quartz-enhanced photoacoustic spectroscopy (QEPAS) sensing. Based on finite element analysis, a theoretical simulation model was established to optimize the design of QTF. For performance comparison, a reported T-head QTF and a commercial QTF were also investigated. The designed QTFs have decreased resonant frequency (f0) and increased gap between the two prongs of QTF. The experimentally determined f0 of the T-head QTF, trapezoidal-head QTF, and round-head QTF were 8690.69 Hz, 9471.67 Hz, and 9499.28 Hz, respectively. The corresponding quality (Q) factors were measured as 11,142, 11,411, and 11,874. Compared to the commercial QTF, the resonance frequencies of these QTFs have reduced by 73.45%, 71.07%, and 70.99% while maintaining a comparable Q factor to the commercially mature QTF. Methane (CH4) was chosen as the analyte to verify the QTFs’ performance. Compared with the commercial QTF, the signal-to-noise ratio (SNR) of the CH4–QEPAS system based on the T-head QTF, trapezoidal-head QTF, and round-head QTF has been improved by 1.75 times, 2.96 times, and 3.26 times, respectively. The performance of the CH4–QEPAS sensor based on the QTF with the best performance of the round-head QTF was investigated in detail. The results indicated that the CH4–QEPAS sensor based on the round-head QTF exhibited an excellent linear concentration response. Furthermore, a minimum detection limit (MDL) of 0.87 ppm can be achieved when the system’s average time was 1200 s.
Effective enhancement of the non-Hermitian corner skin effect in reciprocal photonic crystals
Authors: Wang Xilan , Hao Ran , Fan Pengtao , Hu Luoshu , Ye Bilin , Zou Yonggang , Jin Shangzhong
Published: January 2024

With the rich physical phenomena arising from non-Hermitian systems, the non-Hermitian skin effect (NHSE) has become a current research hotspot. Nowadays, the corner skin effect based on non-reciprocal photonic crystals has been proposed. Considering the complexity of realizing non-reciprocity, the corner skin effect based on reciprocal photonic crystals is well worth investigating. In this Letter, a non-Hermitian reciprocal geometry-dependent corner skin effect based on two-dimensional photonic crystals is presented, which is manifested as the distribution of eigenstates on the corners of a particular geometry by applying open boundary conditions in both directions of photonic crystals. For the better application of the NHSE in the future, such as highly sensitive sensors and lasers, a new, to the best of our knowledge, method that can effectively enhance the performance of the NHSE in photonic crystals is proposed. The method introduces both gain and loss in an ideal photonic crystal to enhance the non-Hermitian specificity of the system, which improves the performance of the non-Hermitian corner skin effect of photonic crystals by 64.5%. Furthermore, this geometry-dependent corner skin effect is corroborated with the spectral topology.
Controlling atom-photon bound states in a coupled resonator array with a two-level quantum emitter
Authors: Lu Zelin , Li Jing , Lu Jing , Zhou Lan
Published: January 2024

We consider a one-dimensional (1D) coupled-resonator array (CRA), where a two-level quantum emitter (2LE) is electric-dipole coupled to the modes of two adjacent resonators. We investigate the energy spectrum, the photon probability distribution of the bound states, and the emission process of the 2LE into the CRA vacuum. A quantum phase transition is found which is characterized by the change of the number of the out-of-band discrete levels. The condition for this change is also presented. The photon wave functions of bound states are found to be asymmetry around the position of the 2LE when the coupling strengths between the 2LE and the resonator are not equal, and they have the same preferred directions which are primarily determined by the larger one among the coupling strengths. The presence of the atom–photon bound states is manifested in the form of a stationary oscillation or a non-vanishing constant in the long enough time.
Thin film characterization by learning-assisted multi-angle polarized microscopy
Authors: Cao Zhaolou , Chen Yunyun , Xian Fenglin , Ren Haidong , Tu Bing
Published: January 2024

Thin film characterization is a necessary step in the semiconductor industry and nanodevice fabrication. In this work, we report a learning-assisted method to conduct the measurement based on a multi-angle polarized microscopy. By illuminating the film with a tightly focused vectorial beam with space-polarization nonseparability, the angle-dependent reflection coefficients are encoded into the reflected intensity distribution. The measurement is then transformed into an optimization problem aiming at minimizing the discrepancy between measured and simulated image features. The proposed approach is validated by numerical simulation and experimental measurements. As the method can be easily implemented with a conventional microscope, it provides a low cost solution to measure film parameters with a high spatial resolution and time efficiency.
Pyrethroid susceptibility reversal in Aedes aegypti: A longitudinal study in Tapachula, Mexico
Authors: Penilla-Navarro Patricia , Solis-Santoyo Francisco , Lopez-Solis Alma , Rodriguez Americo D. , Vera-Maloof Farah , Lozano Saul , Contreras-Mejía Elsa , Vázquez-Samayoa Geovanni , Torreblanca-Lopez Rene , Perera Rushika , Black IV William C. , Saavedra-Rodriguez Karla
Published: January 2024

Pyrethroid resistance in Aedes aegypti has become widespread after almost two decades of frequent applications to reduce the transmission of mosquito-borne diseases. Because few insecticide classes are available for public health use, insecticide resistance management (IRM) is proposed as a strategy to retain their use. A key hypothesis of IRM assumes that negative fitness is associated with resistance, and when insecticides are removed from use, susceptibility is restored. In Tapachula, Mexico, pyrethroids (PYRs) were used exclusively by dengue control programs for 15 years, thereby contributing to selection for high PYR resistance in mosquitoes and failure in dengue control. In 2013, PYRs were replaced by organophosphates—insecticides from a class with a different mode of action. To test the hypothesis that PYR resistance is reversed in the absence of PYRs, we monitored Ae. aegypti’s PYR resistance from 2016 to 2021 in Tapachula. We observed significant declining rates in the lethal concentration 50 (LC50), for permethrin and deltamethrin. For each month following the discontinuation of PYR use by vector control programs, we observed increases in the odds of mosquitoes dying by 1.5% and 8.4% for permethrin and deltamethrin, respectively. Also, knockdown-resistance mutations (kdr) in the voltage-gated sodium channel explained the variation in the permethrin LC50s, whereas variation in the deltamethrin LC50s was only explained by time. This trend was rapidly offset by application of a mixture of neonicotinoid and PYRs by vector control programs. Our results suggest that IRM strategies can be used to reverse PYR resistance in Ae. aegypti; however, long-term commitment by operational and community programs will be required for success.
Prevalence and circulant genotypes of Chlamydia trachomatis in university women from cities in the Brazilian Amazon
Authors: dos Santos Leonardo Miranda , Vieira Maria Renata Mendonça dos Santos , Vieira Rodrigo Covre , Silva Lídia Bolivar da Luz , de Macêdo Geraldo Mariano Moraes , Miranda Angélica Espinosa , Brasiliense Danielle Murici , e Guimarães Ricardo José de Paula Souza , Sousa Edivaldo Costa , Ferrari Stephen Francis , Pinheiro Helder Henrique Costa , Ishikawa Edna Aoba Yassui , de Sousa Maísa Silva
Published: January 2024

Background

Approximately 80% of infected women infected by Chlamydia trachomatis are asymptomatic, although this infection can lead to serious complications in the female reproductive tract. Few data on Chlamydia infection and genotypes are available in Amazonian communities.

Objectives

To describe the prevalence of and associated factors and to identify the genotypes of sexual C. trachomatis infection in female university students in different urban centers (capital and interiors) in the Brazilian state of Pará, in the eastern Amazon region.

Methods

A cross-sectional study was performed among young women attending public universities in four different urban centers in the eastern Amazon region. They were invited to participate in the studt and cervical secretions were collected for molecular diagnosis of C. trachomatis. We utilized amplification of the ompA gene by nested PCR. Positive samples were genotyped by nucleotide sequencing. Study participants completed a questionnaire on social, epidemiological, and reproductive health variables. A Qui-square and Binominal regression test were used to evaluate the degree of association of these variables with the infection.

Results

A total of 686 female students was included in the study. The overall prevalence of C. trachomatis was 11.2% (77/686). The prevalence of this infection was higher in interiors (15.2% vs 9.5%/ p: 0.0443). Female university students who do not have a sexual partner (11.8%/p <0.008), who do not use a condom in their sexual relations (17.8%/p <0.0001) and who reported having suffered a miscarriage (32%/p <0.0001) have high chances of acquiring this sexual infection. The ompA gene was sequenced in only 33 (42.8%) samples, revealing the genotype J was the most frequent (27.2% [9/33]), followed by genotypes D (24.2% [8/33]), and then genotypes F (18.2% [6/33]), E (15.1% [5/33]) K (6.1% [2/33]), Ia (6.1% [2/33]), and G (3.1% [1/33]).

Conclusions

The high prevalence of sexual infection by C. trachomatis in the female university students from the interior of the state of Pará, individuals with no fixed sexual partner, those that had had a miscarriage, the students that do not use condoms in their sexual relations. The genotype J of C. trachomatis genotypes was the most frequent. These data are important to help defining the epidemiological effects of chlamydial infections in Amazonian populations.
Changes in nutritional, health benefits, and pharmaceutical potential of raw and roasted tropical almond (Terminalia catappa Linn.) nuts from Nigeria
Authors: Chukwuma Ifeoma Felicia , Ossai Emmanuel Chekwube , Nworah Florence Nkechi , Apeh Victor Onukwube , Abiaziem Emmanuel Osinachi , Iheagwam Franklyn Nonso , Skendrović Hanna , Juchniewicz Szymon , Leicht Katarzyna , Okpala Charles Odilichukwu R. , Korzeniowska Małgorzata
Published: January 2024

Tropical almond (Terminalia catappa Linn.) is highly distributed within the tropics, but appears rather underutilized in developing countries like Nigeria. Specifically, relevant information regards the nutritional, health benefits, and pharmaceutical potential of roasted T. catappa nuts remains scanty. Comparing both raw and roasted T. catappa nuts should provide additional information especially from product development and potential commercial prospect standpoints. The changes in nutritional, health benefits, and pharmaceutical potentials of raw and roasted T. catappa nuts were, therefore, investigated. Whereas the raw T. catappa nuts obtained significantly (p < 0.05) higher protein, ash, moisture, crude fiber, as well as vitamins C, and B1-3 compared to the roasted ones, some contents like carbohydrates, energy, vitamin A, calcium, manganese, zinc, hydrogen cyanide, as well as oxalate would noticeably change (p < 0.05) after the roasting process. Twenty phytochemicals were identified in both raw and roasted samples with the concentrations of quinine, ribalinidine, sapogenin, flavan-3-ol and tannin significantly reduced, while catechin seemed enhanced upon roasting. Promising drug-likeness, pharmacokinetic properties, and safety profiles could be predicted among the phytochemicals. Overall, roasting T. catappa nuts should enhance the nutritional contents, which could aid both absorption and palatability.
Large regional variation in cardiac closure procedures to prevent ischemic stroke in Switzerland a population-based small area analysis
Authors: Stoller Nina , Wertli Maria M. , Haynes Alan G. , Chiolero Arnaud , Rodondi Nicolas , Panczak Radoslaw , Aujesky Drahomir
Published: January 2024

Background

Percutaneous closure of a patent foramen ovale (PFO) or the left atrial appendage (LAA) are controversial procedures to prevent stroke but often used in clinical practice. We assessed the regional variation of these interventions and explored potential determinants of such a variation.

Methods

We conducted a population-based analysis using patient discharge data from all Swiss hospitals from 2013–2018. We derived hospital service areas (HSAs) using patient flows for PFO and LAA closure. We calculated age-standardized mean procedure rates and variation indices (extremal quotient [EQ] and systematic component of variation [SCV]). SCV values >5.4 indicate a high and >10 a very high variation. Because the evidence on the efficacy of PFO closure may differ in patients aged <60 years and ≥60 years, age-stratified analyses were performed. We assessed the influence of potential determinants of variation using multilevel regression models with incremental adjustment for demographics, cultural/socioeconomic, health, and supply factors.

Results

Overall, 2574 PFO and 2081 LAA closures from 10 HSAs were analyzed. The fully adjusted PFO and LAA closure rates varied from 3 to 8 and from 1 to 9 procedures per 100,000 persons per year across HSAs, respectively. The regional variation was high with respect to overall PFO closures (EQ 3.0, SCV 8.3) and very high in patients aged ≥60 years (EQ 4.0, SCV 12.3). The variation in LAA closures was very high (EQ 16.2, SCV 32.1). In multivariate analysis, women had a 28% lower PFO and a 59% lower LAA closure rate than men. French/Italian language areas had a 63% lower LAA closure rate than Swiss German speaking regions and areas with a higher proportion of privately insured patients had a 86% higher LAA closure rate. After full adjustment, 44.2% of the variance in PFO closure and 30.3% in LAA closure remained unexplained.

Conclusions

We found a high to very high regional variation in PFO closure and LAA closure rates within Switzerland. Several factors, including sex, language area, and insurance status, were associated with procedure rates. Overall, 30–45% of the regional procedure variation remained unexplained and most probably represents differing physician practices.
Robustness of open source community multi-project knowledge collaboration network based on structural hole theory
Authors: Lei Shaojuan , Wang Chenzhi , Zhang Taoge , Liu Xinhua
Published: January 2024

Nodes in the structural hole position play a key role in the multi-project network of the open source community (OSC). This paper studies the robustness of this network based on structural hole theory. First, a semantic-based multi-project KCN is constructed, and four node types are identified: knowledge contribution nodes, knowledge dissemination nodes, structural hole nodes (SHNs) and opinion leader nodes. Second, a robustness analysis model of the edge failures of these four key nodes is constructed. Third, a simulation test is conducted on the proposed model using empirical data from the Local Motors multi-project OSC. The results show that the KCN has the lowest robustness when facing the edge failure of opinion leader nodes, followed by knowledge dissemination nodes, knowledge contribution nodes, SHNs and random nodes. The edge failure of opinion leader nodes causes the lowest network robustness because of the propagation effect of these nodes. Additionally, SHN failure has only a small initial impact on connectivity, whereas knowledge collaboration efficiency decreases rapidly (i.e., the edge failure of SHNs causes the network to enter a state of high connectivity and low efficiency). The proposed model can be used to provide comprehensive and targeted management guidance for OSC development.
Assets for integrating task-sharing strategies for hypertension within HIV clinics: Stakeholder’s perspectives using the PEN-3 cultural model
Authors: Iwelunmor Juliet , Maureen Obionu Ifeoma , Shedul Gabriel , Anyiekere Ekanem , Henry Daniel , Aifah Angela , Obiezu-Umeh Chisom , Nwaozuru Ucheoma , Onakomaiya Deborah , Rakhra Ashlin , Mishra Shivani , Hade Erinn M. , Kanneh Nafesa , Lew Daphne , Bansal Geetha P. , Ogedegbe Gbenga , Ojji Dike
Published: January 2024

Background

Access to antiretroviral therapy has increased life expectancy and survival among people living with HIV (PLWH) in African countries like Nigeria. Unfortunately, non-communicable diseases such as cardiovascular diseases are on the rise as important drivers of morbidity and mortality rates among this group. The aim of this study was to explore the perspectives of key stakeholders in Nigeria on the integration of evidence-based task-sharing strategies for hypertension care (TASSH) within existing HIV clinics in Nigeria.

Methods

Stakeholders representing PLWH, patient advocates, health care professionals (i.e. community health nurses, physicians and chief medical officers), as well as policymakers, completed in-depth qualitative interviews. Stakeholders were asked to discuss facilitators and barriers likely to influence the integration of TASSH within HIV clinics in Akwa Ibom, Nigeria. The interviews were transcribed, keywords and phrases were coded using the PEN-3 cultural model as a guide. Framework thematic analysis guided by the PEN-3 cultural model was used to identify emergent themes.

Results

Twenty-four stakeholders participated in the interviews. Analysis of the transcribed data using the PEN-3 cultural model as a guide yielded three emergent themes as assets for the integration of TASSH in existing HIV clinics. The themes identified are: 1) extending continuity of care among PLWH; 2) empowering health care professionals and 3) enhancing existing workflow, staff motivation, and stakeholder advocacy to strengthen the capacity of HIV clinics to integrate TASSH.

Conclusion

These findings advance the field by providing key stakeholders with knowledge of assets within HIV clinics that can be harnessed to enhance the integration of TASSH for PLWH in Nigeria. Future studies should evaluate the effect of these assets on the implementation of TASSH within HIV clinics as well as their effect on patient-level outcomes over time.
Leukocyte telomere length and sarcopenia-related traits: A bidirectional Mendelian randomization study
Authors: Wang Dingkun , Li Chenhao , Zhang Xinwen , Li Yihao , He Junhua , Guo Xiaoming
Published: January 2024

Accumulating evidence indicated that leukocyte telomere length (LTL) was related to sarcopenia. However, it is still not clear whether the association of changes in LTL with sarcopenia is likely to be causal, or could be explained by reverse causality. Thus, we carried on bidirectional Mendelian randomization (MR) and multivariable MR analyses to identify the causal relationship between LTL and sarcopenia-related traits. Summary-level data and independent variants used as instruments came from large genome-wide association studies of LTL (472,174 participants), appendicular lean mass (450,243 participants), low grip strength (256,523 participants), and walking pace (450,967 participants). We identified suggestive association of longer LTL with larger appendicular lean mass [odds ratio (OR) = 1.053; 95% confidence interval (CI), 1.009–1.099; P = 0.018], and causal association of longer LTL with a lower risk of low grip strength (OR = 0.915; 95% CI, 0.860–0.974; P = 0.005). In the reverse MR analysis, we also observed a positive causal association between walking pace and LTL (OR = 1.252; 95% CI, 1.121–1.397; P < 0.001). Similar results can be repeated in sensitivity analyses. While in the multivariable MR analysis, the estimate of the impact of walking pace on LTL underwent a transformation after adjusting for T2DM (OR = 1.141; 95%CI: 0.989–1.317; P = 0.070). The current MR analysis supported a causal relationship between shorter telomere length and both low muscle mass and strength. Additionally, walking pace may affect LTL through T2DM.
Leader cells mechanically respond to aligned collagen architecture to direct collective migration
Authors: Lichtenberg Jessanne Y. , Ramamurthy Ella , Young Anna D. , Redman Trey P. , Leonard Corinne E. , Das Swadesh K. , Fisher Paul B. , Lemmon Christopher A. , Hwang Priscilla Y.
Published: January 2024

Leader cells direct collective migration through sensing cues in their microenvironment to determine migration direction. The mechanism by which leader cells sense the mechanical cue of organized matrix architecture culminating in a mechanical response is not well defined. In this study, we investigated the effect of organized collagen matrix fibers on leader cell mechanics and demonstrate that leader cells protrude along aligned fibers resulting in an elongated phenotype of the entire cluster. Further, leader cells show increased mechanical interactions with their nearby matrix compared to follower cells, as evidenced by increased traction forces, increased and larger focal adhesions, and increased expression of integrin-α2. Together our results demonstrate changes in mechanical matrix cues drives changes in leader cell mechanoresponse that is required for directional collective migration. Our findings provide new insights into two fundamental components of carcinogenesis, namely invasion and metastasis.
Observational studies generate misleading results about the health effects of air pollution: Evidence from chronic air pollution and COVID-19 outcomes
Authors: Conte Marc N. , Gordon Matthew , Swartwood Nicole A. , Wilwerding Rachel , Yu Chu A. (Alex)
Published: January 2024

Several observational studies from locations around the globe have documented a positive correlation between air pollution and the severity of COVID-19 disease. Observational studies cannot identify the causal link between air quality and the severity of COVID-19 outcomes, and these studies face three key identification challenges: 1) air pollution is not randomly distributed across geographies; 2) air-quality monitoring networks are sparse spatially; and 3) defensive behaviors to mediate exposure to air pollution and COVID-19 are not equally available to all, leading to large measurement error bias when using rate-based COVID-19 outcome measures (e.g., incidence rate or mortality rate). Using a quasi-experimental design, we explore whether traffic-related air pollutants cause people with COVID-19 to suffer more extreme health outcomes in New York City (NYC). When we address the previously overlooked challenges to identification, we do not detect causal impacts of increased chronic concentrations of traffic-related air pollutants on COVID-19 death or hospitalization counts in NYC census tracts.
The role of operators in sustainable whale-watching tourism: Proposing a continuous training framework
Authors: Affatati Alice , Scaini Chiara , Scaini Anna
Published: January 2024

Whale watching is considered a form of green tourism, but can affect marine ecosystems, impacting cetaceans’ behavior and potentially increasing acoustic pollution. A more sustainable whale-watching practice should employ a comprehensive approach involving all stakeholders, but whale-watching operators are rarely involved. We propose a method to assess whale–watching operators’ perceptions regarding the possible effects of their activity on marine fauna and preferred mitigation solutions, by means of online questionnaires and website communication strategies. Results from Canadian whale-watching operators show that they observe regulations regarding distance to whales but only partially perceive general vessels’ impacts on fauna. Three recognized whale-watching experts identify the need for continuous training targeted at operators, which should include the impacts on marine ecosystems. A continuous training framework is proposed that targets whale-watching operators in addition to tourists, and involves scientists in several steps of the approach. This study serves as a starting point to involve operators’ in order to advance towards a sustainable whale-watching tourism.
The landscape of SETBP1 gene expression and transcription factor activity across human tissues
Authors: Whitlock Jordan H. , Wilk Elizabeth J. , Howton Timothy C. , Clark Amanda D. , Lasseigne Brittany N.
Published: January 2024

The SET binding protein 1 (SETBP1) gene encodes a transcription factor (TF) involved in various cellular processes. Variants in SETBP1 can result in three different diseases determined by the introduction (germline vs. somatic) and location of the variant. Germline variants cause the ultra-rare pediatric Schinzel Giedion Syndrome (SGS) and SETBP1 haploinsufficiency disorder (SETBP1-HD), characterized by severe multisystemic abnormalities with neurodegeneration or a less severe brain phenotype accompanied by hypotonia and strabismus, respectively. Somatic variants in SETBP1 are associated with hematological malignancies and cancer development in other tissues in adults. To better understand the tissue-specific mechanisms involving SETBP1, we analyzed publicly available RNA-sequencing (RNA-seq) data from the Genotype-Tissue Expression (GTEx) project. We found SETBP1 and its known target genes were widely expressed across 31 adult human tissues. K-means clustering identified three distinct expression patterns of SETBP1 targets across tissues. Functional enrichment analysis (FEA) of each cluster revealed gene sets related to transcriptional regulation, DNA binding, and mitochondrial function. TF activity analysis of SETBP1 and its target TFs revealed tissue-specific TF activity, underscoring the role of tissue context-driven regulation and suggesting its impact in SETBP1-associated disease. In addition to uncovering tissue-specific molecular signatures of SETBP1 expression and TF activity, we provide a Shiny web application to facilitate exploring TF activity across human tissues for 758 TFs. This study provides insight into the landscape of SETBP1 expression and TF activity across 31 non-diseased human tissues and reveals tissue-specific expression and activity of SETBP1 and its targets. In conjunction with the web application we constructed, our framework enables researchers to generate hypotheses related to the role tissue backgrounds play with respect to gene expression and TF activity in different disease contexts.
Comprehensive characterization of coding and non-coding single nucleotide polymorphisms of the Myoneurin (MYNN) gene using molecular dynamics simulation and docking approaches
Authors: Mou Sadia Islam , Sultana Tamanna , Chatterjee Dipankor , Faruk Md. Omar , Hosen Md. Ismail
Published: January 2024

Genome-wide association studies (GWAS) identified a coding single nucleotide polymorphism, MYNN rs10936599, at chromosome 3q. MYNN gene encodes myoneurin protein, which has been associated with several cancer pathogenesis and disease development processes. However, there needed to be a more detailed characterization of this polymorphism’s (and other coding and non-coding polymorphisms) structural, functional, and molecular impact. The current study addressed this gap and analyzed different properties of rs10936599 and non-coding SNPs of MYNN via a thorough computational method. The variant, rs10936599, was predicted functionally deleterious by nine functionality prediction approaches, like SIFT, PolyPhen-2, and REVEL, etc. Following that, structural modifications were estimated through the HOPE server and Mutation3D. Moreover, the mutation was found in a conserved and active residue, according to ConSurf and CPORT. Further, the secondary structures were predicted, followed by tertiary structures, and there was a significant deviation between the native and variant models. Similarly, molecular simulation also showed considerable differences in the dynamic pattern of the wildtype and mutant structures. Molecular docking revealed that the variant binds with better docking scores with ligand NOTCH2. In addition to that, non-coding SNPs located at the MYNN locus were retrieved from the ENSEMBL database. These were found to disrupt the transcription factor binding regulatory regions; nonetheless, only two affect miRNA target sites. Again, eight non-coding variants were detected in the testes with normalized expression, whereas HaploReg v4.1 unveiled annotations for non-coding variants. In summary, in silico comprehensive characterization of coding and non-coding single nucleotide polymorphisms of MYNN gene will assist researchers to work on MYNN gene and establish their association with certain types of cancers.
Association between physical performance and bone mass in community-dwelling postmenopausal Japanese women: The Unzen study
Authors: Suiko Masahiro , Mizukami Satoshi , Arima Kazuhiko , Nakashima Hiroki , Nishimura Takayuki , Tomita Yoshihito , Abe Yasuyo , Tanaka Natsumi , Honda Yuzo , Kojima Michiko , Okawachi Tetsuji , Hasegawa Maiko , Sou Youko , Tsujimoto Ritsu , Kanagae Mitsuo , Osaki Makoto , Aoyagi Kiyoshi
Published: January 2024

Background

Low bone mass is an independent risk factor for osteoporotic fractures. We examined the association between physical performance and bone mass using quantitative ultrasound in community-dwelling postmenopausal Japanese women.

Methods

We conducted a cross-sectional study on 524 community-dwelling postmenopausal Japanese women who were not being administered osteoporosis medications. Physical performance was assessed on the basis of grip strength, chair stand time, and functional reach. The stiffness index was measured as a quantitative ultrasound parameter for heel bone mass.

Results

Physical performance, assessed by grip strength, chair stand time, and functional reach, and the stiffness index significantly decreased with age (both p<0.001). The multiple linear regression analysis showed that grip strength (p = 0.001), chair stand time (p = 0.004), and functional reach (p = 0.048) were significantly associated with the stiffness index after adjusting for age, body mass index, smoking, drinking, and exercise.

Conclusions

Physical performance was significantly associated with heel bone mass in community-dwelling postmenopausal Japanese women.
Stress appraisal in the workplace and its associations with productivity and mood: Insights from a multimodal machine learning analysis
Authors: Awada Mohamad , Becerik Gerber Burcin , Lucas Gale M. , Roll Shawn C.
Published: January 2024

Previous studies have primarily focused on predicting stress arousal, encompassing physiological, behavioral, and psychological responses to stressors, while neglecting the examination of stress appraisal. Stress appraisal involves the cognitive evaluation of a situation as stressful or non-stressful, and as a threat/pressure or a challenge/opportunity. In this study, we investigated several research questions related to the association between states of stress appraisal (i.e., boredom, eustress, coexisting eustress-distress, distress) and various factors such as stress levels, mood, productivity, physiological and behavioral responses, as well as the most effective ML algorithms and data signals for predicting stress appraisal. The results support the Yerkes-Dodson law, showing that a moderate stress level is associated with increased productivity and positive mood, while low and high levels of stress are related to decreased productivity and negative mood, with distress overpowering eustress when they coexist. Changes in stress appraisal relative to physiological and behavioral features were examined through the lenses of stress arousal, activity engagement, and performance. An XGBOOST model achieved the best prediction accuracies of stress appraisal, reaching 82.78% when combining physiological and behavioral features and 79.55% using only the physiological dataset. The small accuracy difference of 3% indicates that physiological data alone may be adequate to accurately predict stress appraisal, and the feature importance results identified electrodermal activity, skin temperature, and blood volume pulse as the most useful physiologic features. Implementing these models within work environments can serve as a foundation for designing workplace policies, practices, and stress management strategies that prioritize the promotion of eustress while reducing distress and boredom. Such efforts can foster a supportive work environment to enhance employee well-being and productivity.
Optimizing and hyper-tuning machine learning models for the water absorption of eggshell and glass-based cementitious composite
Authors: Xia Xiqiao
Published: January 2024

Cementitious composites’ performance degrades in extreme conditions, making it more important to enhance its resilience. To further the adaptability of eco-friendly construction, waste materials are increasingly being repurposed. Cementitious composites deteriorate in both direct and indirect ways due to the facilitation of hostile ion transport by water. The effects of using eggshell and glass powder as partial substitutes for cement and sand in mortar on the water-absorption capacity were investigated using machine learning (ML) modeling techniques such as Gene Expression Programming (GEP) and Multi Expression Programming (MEP). To further assess the importance of inputs, sensitivity analysis and interaction research were carried out. The water absorption property of cementitious composites was precisely estimated by the generated ML models. It was noted that the MEP model, with an R2of 0.90, and the GEP model, with an R2of 0.88, accurately predicted results. The sensitivity analysis revealed that the absorption capacity of the mortar was most affected by the presence of eggshell powder, sand, and glass powder. GEP and MEP model’s significance lies in the fact that they offer one-of-a-kind mathematical formulas that can be applied to the prediction of features in another database. The mathematical models resulting from this study can help scientists and engineers rapidly assess, enhance, and rationalize mixture proportioning. The built models can theoretically compute the water absorption of cement mortar made from eggshell powder and glass powder based on varied input parameters, resulting in cost and time savings.
Genetic algorithm-enhanced linear quadratic control for balancing bicopter system with non-zero set point
Authors: Apriaskar Esa , Prastiyanto Dhidik , Utomo Aryo Baskoro , Manaf Akhyar Abdillah , Amelia Ilya , Ilham Dimas Alfarizky , Bilqis Viyola Lokahita , Photong Chonlatee
Published: January 2024

Bicopter is an unmanned aerial vehicle (UAV) with the advantage of saving energy consumption. However, the unique two rotors design presents a challenge in designing a controller that achieves good stability, fast settling time, and the ability to overcome oscillations simultaneously. This article proposes a new control method for bicopter that uses a genetic algorithm optimization approach in the linear quadratic (LQ-GA) control method. The GA is used to search for the best weighting matrix parameters, Q and R, in the Linear Quadratic (LQ) control scheme. The proposed control method was tested on a balancing bicopter test platform with an input in the form of difference in pulse width modulation (PWM) signals for both rotors and an output in the form of roll angle. The control system was evaluated based on the stability of the transient response and the generated control signal. The results of the tests showed that the proposed LQ-GA control method has better stability, faster settling time, and smaller overshoot than the existing PI and standard LQ control methods. Therefore, the proposed LQ-GA control method is the most suitable for use in a balancing bicopter system with a non-zero setpoint.
Investigation of the usage of zigzag transformers to reduce harmonics distortion in distribution systems
Authors: Gumilar Langlang , Wicaksono Ibram Adib , Afandi Arif Nur , Samat Ahmad Asri Abd , Sias Quota Alief
Published: January 2024

The increasing use of power electronics in various sectors leads to harmonic distortion in electric power systems, affecting power quality and equipment longevity. While harmonic filters have been used to address this issue, they are limited in effectiveness, particularly in reducing distortion across the entire distribution system. This study aims to reduce harmonic distortion using a zigzag transformer as a more comprehensive solution in mitigating harmonic distortion throughout the entire distribution system. In this research, the zigzag transformer was placed at point common coupling to reduce harmonic distortion in the distribution system as a whole. A zigzag transformer connection was configured by connecting either three windings of a single-phase transformer or one winding of a three-phase transformer. Based on the results of this research, the total harmonic distortion (THD) value has decreased from 25.26 % to 2.48 % following the implementation of the zigzag transformer. This substantial decrease in THD concludes the zigzag transformer's effectiveness as a solution for improving power quality in electrical distribution systems.
Design and CFD simulation of guide vane for multistage Savonius wind turbine
Authors: Devin Dionisius , Halim Levin , Arthaya Bagus Made , Chandra Jonathan
Published: January 2024

This study proposes improving the performance of a fixed-axis multistage Savonius wind turbine by integrating a sixbladed guide vane. Guide vanes aim to direct the incoming wind towards the blades of the Savonius wind turbine so that it can increase the performance value of the turbine itself. There are two methods, the first method is computational fluid dynamics (CFD) simulation to evaluate the best performance guide vane angle variations. The second method is implementing real conditions using 3 m/s until 4.2 m/s wind speed. The implementation of the guide vane to the wind turbine will consider four (4) variants of angles (0°, 20°, 40°, and 60°). The purpose of testing with four kinds of guide vane angles is to find out which guide vane angle can provide the best results among other guide vane angles. This research proposed the initial design of the guide vane addition to the multistage Savonius wind turbine with a fixed rotary axis. From the CFD simulation, the implementation of a guide vane can improve the performance of the multistage Savonius wind turbine with a fixed rotary axis. On the other hand, for the proposed initial design in this research, the 20° angle of guide vane gives the best result compared to the 0°, 40°, 60°, and without guide vane.
Systemic Reconstruction of Legal Norms: Linguistic Aspect
Authors: Belous Anastasiya , Voronin Maxim , Avramenko Anton
Published: January 2024

This article continues the study of the problem of systemic reconstruction of legal norms (See: Voronin, M. V., Avramenko, A. V., Belous, A. A. (2022). Systematic reconstruction of legal norms: needs, methodology, prospects. Legal world, 9, 30-38).

The aim of the present article is to develop and describe a method of systemic reconstruction of legal norms in its linguistic aspect to solve the problem of converting legal texts in natural language into a database. The advantage of the method is a comprehensive interdisciplinary approach that combines jurisprudence, linguistics and subject matter expertise. This approach ensures high quality of the converted data.

Drawing on the case of The Good Manufacturing Practice (GMP), the substantial factors that make it difficult to interpret unambiguously the regulatory material are analyzed; with these factors in view, a model of a formalized wording is proposed. The model makes it possible to present normative material in a standardized form and to combine it into a database. Based on the reconstruction experience of the Rules of GMP, lexical and syntactic transformations of the source text, as well as typical semantic tasks that the expert solves at the synthesis stage are described. The article shows the effectiveness of transformational grammar rules at that stage to achieve semantic equivalence of the original and transformed textual information within the framework of the described method.

The method of systemic reconstruction in its linguistic aspect is significant for further work related to improving the language of technical regulations.