bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of COVID-19 outbreak and perceptions of people towards household waste management chain in Nepal
Authors: Acharya Ashis , Bastola Govinda , Modi Bindu , Marhatta Asmi , Belbase Suraj , Lamichhane Ganesh , Gyawali Narayan , Dahal Ranjan Kumar
Published: June 2021

The spread of COVID-19 is posing significant challenges to the household (HH) waste management sectors putting waste personnel and concerned bodies under massive pressure. The chain of collection, segregation, recycling, and disposal of household generated wastes is interrupted. This study aimed to assess how the household waste management chain was disrupted by novel coronavirus in Nepal and find the perception of the people towards the existing household waste management system (HHWMS). A descriptive online survey was carried out among 512 people using a cross-sectional research design and data was collected through a self-administered questionnaire method. Both descriptive, as well as inferential tests, were conducted using SPSS software. The finding of this study showed that 62.3% of respondents were not satisfied with the present HHWMS. Furthermore, there was a significant association of the satisfaction level of household waste management during coronavirus outbreak with gender, waste volume change in lockdown, PPE for waste collectors, and education on waste handling techniques provided by the government sector at 5% level of significance (p < 0.05). Proper HH waste management has become a challenge, and to address this some innovative works such as awareness programs for people, health and hygiene related support to waste workers, and effective policy formulation and implementation should be done by the Government of Nepal.
Measures of excess $$ \dot{\mathrm{V}} $$CO2 and recovery $$ \dot{\mathrm{V}} $$CO2 as indices of performance fatigability during exercise: a pilot study
Authors: Wooten Liana C. , Neville Brian T. , Keyser Randall E.
Published: June 2021

Background

The severity of performance fatigability and the capacity to recover from activity are profoundly influenced by skeletal muscle energetics, specifically the ability to buffer fatigue-inducing ions produced from anaerobic metabolism. Mechanisms responsible for buffering these ions result in the production of excess carbon dioxide (CO2) that can be measured as expired CO2 ($$ \dot{\mathrm{V}} $$

V
̇

CO2) during cardiopulmonary exercise testing (CPET). The primary objective of this study was to assess the feasibility of select assessment procedures for use in planning and carrying out interventional studies, which are larger interventional studies investigating the relationships between CO2 expiration, measured during and after both CPET and submaximal exercise testing, and performance fatigability.

Methods

Cross-sectional, pilot study design. Seven healthy subjects (30.7±5.1 years; 5 females) completed a peak CPET and constant work-rate test (CWRT) on separate days, each followed by a 10-min recovery then 10-min walk test. Oxygen consumption ($$ \dot{\mathrm{V}} $$

V
̇

O2) and $$ \dot{\mathrm{V}} $$

V
̇

CO2 on- and off-kinetics (transition constant and oxidative response index), excess-$$ \dot{\mathrm{V}} $$

V
̇

CO2, and performance fatigability severity scores (PFSS) were measured. Data were analyzed using regression analyses.

Results

All subjects that met the inclusion/exclusion criteria and consented to participate in the study completed all exercise testing sessions with no adverse events. All testing procedures were carried out successfully and outcome measures were obtained, as intended, without adverse events. Excess-$$ \dot{\mathrm{V}} $$

V
̇

CO2 accounted for 61% of the variability in performance fatigability as measured by $$ \dot{\mathrm{V}} $$

V
̇

O2 on-kinetic ORI (ml/s) (R2=0.614; y = 8.474x − 4.379, 95% CI [0.748, 16.200]) and 62% of the variability as measured by PFSS (R2=0.619; y =  − 0.096x + 1.267, 95% CI [−0.183, −0.009]). During CPET, $$ \dot{\mathrm{V}} $$

V
̇

CO2 -off ORI accounted for 70% (R2=0.695; y = 1.390x − 11.984, 95% CI [0.331, 2.449]) and $$ \dot{\mathrm{V}} $$

V
̇

CO2 -off Kt for 73% of the variability in performance fatigability measured by $$ \dot{\mathrm{V}} $$

V
̇

O2 on-kinetic ORI (ml/s) (R2=0.730; y = 1.818x − 13.639, 95% CI [0.548, 3.087]).

Conclusion

The findings of this study suggest that utilizing $$ \dot{\mathrm{V}} $$

V
̇

CO2 measures may be a viable and useful addition or alternative to $$ \dot{\mathrm{V}} $$

V
̇

O2 measures, warranting further study. While the current protocol appeared to be satisfactory, for obtaining select cardiopulmonary and performance fatigability measures as intended, modifications to the current protocol to consider in subsequent, larger studies may include use of an alternate mode or measure to enable control of work rate constancy during performance fatigability testing following initial CPET.
Antidiarrhoeal potentials of methanol bark extract of Hymenocardia Acida Tul (Euphorbiaceae) in laboratory animals
Authors: Usman Abba Musab , Danjuma Nuhu Muhammad , Ya’u Jamilu , Ahmad Muslim Muhammad , Alhassan Zakariyya , Abubakar Yusuf Muhammad , Ahmad Mubarak Hussaini
Published: June 2021

Background

The plant Hymenocardia acida (Euphorbiaceae) is utilized as herbal preparation against diarrhoea, dysentery and other diseases. We aimed to determine the antidiarrhoeal potentials of Hymenocardia acida (MEHA) stem bark in vivo and in vitro. Preliminary phytochemical contents, as well as the acute toxicity effect of the extract, were investigated based on standard experimental methods. The antidiarrhoeal properties of the MEHA at 150, 300 and 600 mg/kg were studied against diarrhoea induced by castor oil, intestinal fluid accumulation, as well as intestinal movement tests using distilled water (10 ml/kg) and loperamide/atropine sulphate as the control groups. Besides, the in vitro effects of the extract (8 × 10−2–640 × 10−2 mg/ml) on the rabbit jejunum and guinea-pig ileum were evaluated.

Results

Phytochemical screening showed alkaloids, glycoside, saponins, tannins, triterpenes, flavonoids and steroids in the MEHA. The median lethal dose (LD50) of the MEHA after oral administration was approximately greater than 2000 mg/kg. The MEHA declined the diarrhoea onset and remarkably decreased the number of watery stools in the group that received 300 and 600 mg/kg. It also elicited a remarkable and non-dose-dependent reduction in the intestinal fluid volume. At 1000 mg/kg, the MEHA significantly inhibited the charcoal movement. In addition, the MEHA (8 × 10−2–640 × 10−2 mg/ml) elicited a remarkable decrease in the contractility of the rabbit jejunum over time and relaxed the guinea pig ileum. Besides, it showed concentration-dependent attenuation of the acetylcholine and histamine-induced contraction.

Conclusion

The extract under investigation revealed promising antidiarrhoeal properties that justified its traditional claim for use against diarrhoea.
Removing the Courant-Friedrichs-Lewy stability criterion of the explicit time-domain very high degree spectral-element method with eigenvalue perturbation
Authors: Lyu Chao , Capdeville Yann , Lu Gang , Zhao Liang
Published: June 2021

The explicit time-domain spectral-element method (SEM) for synthesizing seismograms has gained tremendous credibility within the seismological community at all scales. Although the recent introduction of nonperiodic homogenization has addressed the spatial meshing difficulty of the mechanical discontinuities, the Courant-Friedrichs-Lewy (CFL) stability criterion strictly constrains the maximum time step, which still puts a great burden on the numerical simulation. In the explicit time-domain SEM, the source of instability of using a time step beyond the stability criterion is that some unstable eigenvalues of the updated matrix are larger than what can be accurately simulated. We have succeeded in removing the CFL stability condition in explicit time-domain SEM by combining the forward time dispersion-transform method, the eigenvalue perturbation, and the inverse time dispersion-transform method. Our theoretical analyses and numerical experiments in the homogeneous, moderate, and strong heterogeneous models show that this combination can accurately simulate waveforms with time steps several times the size of the CFL limit even toward the Nyquist limit especially for the efficient very high degree SEM, which abundantly saves iteration times without suffering from time-dispersion error. It demonstrates a potential application prospect in some situations such as full-waveform inversion that require multiple numerical simulations for the same model.
Robust high-dimensional seismic data interpolation based on elastic half norm regularization and tensor dictionary learning
Authors: Lan Nanying , Zhang Fanchang , Li Chuanhui
Published: June 2021

Due to the limitations imposed by acquisition cost, obstacles, and inaccessible regions, the originally acquired seismic data are often sparsely or irregularly sampled in space, which seriously affects the ability of seismic data to image underground structures. Fortunately, compressed sensing provides theoretical support for interpolating and recovering irregularly or undersampled data. Under the framework of compressed sensing, we have adopted a robust interpolation method for high-dimensional seismic data, based on elastic half norm regularization and tensor dictionary learning. Inspired by the elastic net, we first develop the elastic half norm regularization as a sparsity constraint, and we establish a robust high-dimensional interpolation model with this technique. Then, considering the multidimensional structure and spatial correlation of seismic data, we introduce a tensor dictionary learning algorithm to train a high-dimensional adaptive tensor dictionary from the original data. This tensor dictionary is used as the sparse transform for seismic data interpolation because it can capture more detailed seismic features to achieve the optimal and fast sparse representation of high-dimensional seismic data. Finally, we solve the robust interpolation model by an efficient iterative thresholding algorithm in the transform space and perform the space conversion by a modified imputation algorithm to recover the wavefields at the unobserved spatial positions. We conduct high-dimensional interpolation experiments on model and field seismic data on a regular data grid. Experimental results demonstrate that this method has superior performance and higher computational efficiency in noise-free and noisy seismic data interpolation, compared to extensively used dictionary learning-based interpolation methods.
Filtered Life: Air Purification, Gender, and Cigarettes in the People's Republic of China
Authors: Kohrman Matthew
Published: June 2021

Air purification in Chinese contexts over the last half century has been generative for a way of being human, what the author calls “filtered life.” This is a materially, aesthetically, and even humorously mediated form of dwelling. In it, people confront ethics and anxieties under conditions of aerosolized ruination. This article sheds special light on links between gender binaries and filtered life. It traces how, prior to the COVID-19 pandemic, scientists, marketers, and many others residing in urban China interacted with air filters in ways textured by the male state. Notably chronicled here is a critique of ecological ruin emergent in homes of the People's Republic of China (PRC), one mutating from ire toward husbands for smoking cigarettes in the home to more recent indictments of men despoiling the environment.
Comparison of the oncogenomic landscape of canine and feline hemangiosarcoma shows novel parallels with human angiosarcoma
Authors: Wong Kim , Ludwig Latasha , Krijgsman Oscar , Adams David J. , Wood Geoffrey A. , van der Weyden Louise
Published: June 2021

Angiosarcoma (AS) is a highly aggressive tumor of blood and lymphatic vessels in humans that shares many similarities with spontaneously occurring hemangiosarcoma (HSA) in dogs and cats. To investigate the genetic suitability of HSA as a model for AS, we sequenced ∼1000 cancer genes in 41 cases of HSA and matched germline tissue: 15 canine visceral HSAs, 13 canine skin HSAs and 13 feline skin HSAs. Analysis of visceral HSAs from dogs presenting with concurrent splenic and cardiac neoplasms showed that the tumors were not independent primaries, consistent with the highly metastatic nature of HSA. Comparison of HSA to AS revealed that several driver genes were recurrently mutated in both species, such as TP53, PIK3CA, ATRX, GRIN2A and LRP1B. Similar to AS, a UV mutational signature was found in a subset of canine cutaneous HSAs and both species show differing mutational profiles between tissue sites. Our characterization of canine and feline HSA demonstrates many important parallels to AS and provides hope that future studies on these cancers will benefit of all three species.
Multiple pools of PP2A regulate spindle assembly, kinetochore attachments and cohesion in Drosophila oocytes
Authors: Jang Janet K. , Gladstein Amy C. , Das Arunika , Shapiro Joanatta G. , Sisco Zachary L. , McKim Kim S.
Published: June 2021

Meiosis in female oocytes lacks centrosomes, the microtubule-organizing centers. In Drosophila oocytes, meiotic spindle assembly depends on the chromosomal passenger complex (CPC). To investigate the mechanisms that regulate Aurora B activity, we examined the role of protein phosphatase 2A (PP2A) in Drosophila oocyte meiosis. We found that both forms of PP2A, B55 and B56, antagonize the Aurora B spindle assembly function, suggesting that a balance between Aurora B and PP2A activity maintains the oocyte spindle during meiosis I. PP2A-B56, which has a B subunit encoded by two partially redundant paralogs, wdb and wrd, is also required for maintenance of sister chromatid cohesion, establishment of end-on microtubule attachments, and metaphase I arrest in oocytes. WDB recruitment to the centromeres depends on BUBR1, MEI-S332 and kinetochore protein SPC105R. Although BUBR1 stabilizes microtubule attachments in Drosophila oocytes, it is not required for cohesion maintenance during meiosis I. We propose at least three populations of PP2A-B56 regulate meiosis, two of which depend on SPC105R and a third that is associated with the spindle.
Risco de captura por assimetria de informação na Agência Nacional do Petróleo, Gás Natural e Biocombustíveis
Authors: Azevedo Pedro Antonio Pereira de , Moreira Marina Figueiredo
Published: June 2021

Entre os estudos para combate à corrupção, destaca-se a linha dos que discutem regulação como resultado da alteração no papel do Estado de executor para regulador de serviços públicos. Nesse cenário, as agências reguladoras são atores destinados a equilibrar as forças de mercado para garantir a prestação desses serviços. Em mercados imperfeitos e sujeitos a falhas, os agentes econômicos podem adquirir informações privilegiadas e tentar capturar os órgãos reguladores, o que se configuraria como uma nova forma de corrupção. Embora haja consolidação do risco de captura no campo teórico, registra-se a ausência de pesquisas empíricas que testem a manifestação do fenômeno. Neste estudo, desenvolve-se pesquisa empírica aplicada a uma agência reguladora nacional para verificar seu risco de captura por assimetria de informação entre o órgão regulador e os respectivos agentes do mercado regulado. Os resultados demonstram que o risco de captura por assimetria de informação pode ser analisado à luz de nove categorias: esforço, diversificação, internacionalização, seleção adversa, risco moral, sinalização, porte da empresa, qualidade e transversalidade.
A nova Reforma Administrativa: O que sabemos e para onde vamos?
Authors: Peci Alketa , Franzese Cibele , Garcia Lopez Felix , Secchi Leonardo , Dias Thiago Ferreira
Published: June 2021

As ondas reformistas da administração pública brasileira não são fenômenos recentes. Ao contrário, esforços de modernização têm sido presentes desde a reforma burocrática do governo Vargas até os dias de hoje, com a proposta da PEC 32/2020. Neste artigo analisamos os contornos da PEC 32/2020, destacando sua ênfase nas políticas de gestão de pessoas, e focamos na questão da estabilidade, uma vez que a proposta busca revisar os vínculos trabalhistas no setor público, sem um diagnostico aprofundado das implicações sistêmicas desta mudança. Por fim, apresentamos as contribuições dos trabalhos reunidos neste número especial, que, vistas em seu conjunto, buscam compreender para qualificar os debates sobre a reforma administrativa. Espera-se que esta edição especial contribua para o debate empírico e teórico em torno das Reformas, para além da agenda do governo atual.
An exploratory study of social media users’ engagement with COVID-19 vaccine-related content
Authors: Al-Zaman Md. Sayeed
Published: June 2021

Background: Facebook, as the world’s most popular social media platform, has been playing various important roles throughout the COVID-19 pandemic, allowing users to produce and share health-related information that both eases and complicates public health communication. However, the characteristics of vaccine-related Facebook content and users’ reaction to the vaccine issue has been an unexplored area to date.

Methods: To fill the previous knowledge-gap, this exploratory study wants to understand the communication climate of Facebook on the COVID-19 vaccine issue, including the nature of dominant content and users’ engagement patterns with them. Therefore, the study analyzes the 10,000 most popular Facebook posts with the highest interactions on the vaccine issue.

Results: The results show that Facebook users prioritize more vaccine-related news links (71.22%) over other content. The declining interactions on the issue suggests that interaction growth mainly depends on positive news on the vaccine. Finally, users’ reaction to the vaccine issue is dominantly positive, though they may show a highly negative attitude toward vaccine misinformation.

Conclusions: A few limitations and strengths of this study are discussed along with values and implications. This study for the first time analyzes Bangla language-based Facebook content related to the COVID-19 vaccine issue, which is largely overlooked in global academic research.
Banking law
Authors: Homenko Elena
Published: June 2021

The textbook contains a systematic presentation of the main institutions of banking law in accordance with the academic discipline "Banking Law", taught at the Department of Banking Law of the Moscow State Law University named after O. E. Kutafin (MSLA). It examines the banking system of the Russian Federation and its structure; the features of credit institutions as subjects of banking law; the legal basis of the national payment system, its relationship with the banking system of Russia; the legal regulation of the deposit insurance system; legislation on bank accounts; the main types of bank loans; currency transactions carried out with the participation of authorized banks, and operations of credit institutions in the securities market. Attention is paid to the ratio of electronic money with electronic means of payment, the mechanism of non-cash payments and the procedure for implementing the institute of payment clearing.
The proposed diagrams and tables facilitate the assimilation of the most difficult questions.
Personnel Management in «Turquoise» Companies
Authors: Sokerina Svetlana
Published: June 2021

Formation of new approaches to personnel management in companies that bring new technologies, products and other innovations to our world is becoming an important task of the modern company management system. Researchers are trying to rethink different control systems and find those methods and technologies that will be effective in the new reality. Among such attempts we can single out Lalu theory, who "painted" companies in different colors and determined the characteristics of multicolored organizations. Among these colors Lalu singles out the "turquoise" companies that appear in new realities more and more often. The article presents the author's view of the processes of personnel management in turquoise companies. The vision is based on the analysis of the features and characteristics of similar companies. An idea has been formed about the image of the company's employees who can be effective in such companies. Ideas on methods and tools for working with personnel are formulated.
Analysis of the Reasons of Personnel Currency Under Covid-19 Preview (on the Example of Russian Post)
Authors: Grihno V. , Simonova M.
Published: June 2021

During the period of coronavirus restrictions, the issue of staff stability is of particular importance, and, as a result, the management of staff turnover. In the difficult economic situation caused by the pandemic, employers had to not only keep the team, not allowing massive layoffs, but also retain valuable workers.

We conducted a survey among the quitting employees in the branches of the Volga Macroregion of the Russian Post. Based on the data obtained, the reasons for dismissal were analyzed during the period of restrictive government measures in connection with the spread of COVID-19 and immediately after the lifting of severe restrictions. The main trends in changes in employee behavior during a pandemic and their impact on staff turnover have been identified.

In the course of the study, the following conclusions were made:

- employees of the organization, in the context of instability in the country caused by COVID-19, are less likely to decide on layoffs, but they still occur, even in such a difficult period of a pandemic and rising unemployment and increase sharply after the lifting of severe restrictions;

- the main reasons for dismissal are still "insufficient wages" and "high intensity of work, heavy physical activity", while the reasons of an everyday nature that can be endured are fading into the background. Thus, an employee makes a decision to dismiss if he is not satisfied with materially significant working conditions;

- due to the peculiarities of the age structure of the organization, the change in the turnover rate, both during severe restrictions and after their relaxation, is not affected by the number of employees leaving the company due to retirement, which changes insignificantly from month to month.
Studying the Issues of Global Digitalization and its Impact on the Organizational Culture of the Enterprise
Authors: Kalenova A.
Published: June 2021

The article is devoted to the theoretical analysis of the concept of organizational culture of the organization. The influence of an active process in the world is the process of digitalization and its impact on the organizational culture of the organization. The analysis of the intensity of the transition of organizations to "Industry 4.0" at the present time is carried out. A key element in the process of transition to innovations has been identified, namely, personnel. A number of problems that enterprises face when implementing new technologies are highlighted. During the consideration of the problem, the provisions that need to be taken into account when switching to innovations are highlighted. The stages of implementing changes in the organizational culture, which will help to reduce the resistance to the introduction of changes, are considered. Specific examples of the impact of organizational culture on organizational processes are presented. In general, the role of organizational culture in the organization is indicated.
The Order of Organization and Registration of Remote Work of the Employee
Authors: Zaharov D. , Kashtanova YEkatyerina
Published: June 2021

This article discusses the features of the organization and design of remote work of an employee. The general provisions of registration of employees are defined. The forms of the necessary organization of interaction between the employee and the organization are described in the form of electronic document management with the use of an enhanced qualified electronic signature, an enhanced unqualified electronic signature, a simple electronic signature, as well as with the use of postal (courier) communication, depending on the types and forms of documents sent. The issues of ownership of the intellectual results of employees 'activities, as well as the possibility and legality of compensation of employees' expenses for necessary equipment and office supplies during work at home are considered. The rules of the organization of work of employees who are on remote work are defined.
Relationship Between Parent and Teacher Reported Executive Functioning and Maladaptive Behaviors in Children With Down Syndrome
Authors: Esbensen Anna J. , Hoffman Emily K. , Shaffer Rebecca C. , Patel Lina R. , Jacola Lisa M.
Published: June 2021

The current study evaluates the concurrent relationship between parent ratings of executive functioning and maladaptive behavior among children and adolescents with Down syndrome and then repeats this evaluation using teacher reports. Parents and teachers of 63 school-age children with Down syndrome rated the child's executive functioning (Behavior Rating Inventory of Executive Function) and behaviors (Achenbach Child Behavior Checklist). For parent and teacher ratings, elevated behavior dysregulation predicted higher levels of rule-breaking, aggressive, and externalizing behavior. For teacher ratings, elevated behavior dysregulation also predicted higher levels of inattention problems. Among both parent and teacher ratings, greater metacognitive difficulties predicted challenges with attention. Understanding the relationship between these constructs has important implications for targets of intervention and developing preventative strategies.
Multiscale dual attention mechanism for fluid segmentation of optical coherence tomography images
Authors: Chen Minghui , Ma Wenfei , Shi Linfang , Li Manqi , Wang Cheng , Zheng Gang
Published: June 2021

Optical coherence tomography (OCT) technology can obtain a clear
retinal structure map, which is greatly beneficial for the diagnosis
of retinopathy. Ophthalmologists can use OCT technology to analyze
information about the retina’s internal structure and changes in
retinal thickness. Therefore, segmentation of retinal layers in images
and screening for retinal diseases have become important goals in OCT
scanning. In this paper, we propose the multiscale dual attention
(MSDA)-UNet network, an MSDA mechanism network for OCT lesion area
segmentation. The MSDA-UNet network introduces position and multiscale
channel attention modules to calculate a global reference for each
pixel prediction. The network can extract the lesion area information
of OCT images of different scales and perform end-to-end segmentation
of the OCT retinopathy area. The network framework was trained and
tested on the same OCT dataset and compared with other OCT fluid
segmentation methods to assess its effectiveness.
Efficient photobleaching of rhodamine 6G by a single UV pulse
Authors: Fort Charles , Bardet Philippe M.
Published: June 2021

While photobleaching can be detrimental in applications focusing on
fluorescence as it lowers the signal strength, it can advantageously
provide non-fluorescent tracers in a fluorescent flow and hence be
implemented in tracking techniques such as molecular tagging
velocimetry (MTV). The photobleaching of rhodamine 6G under a single
UV pulse is described with a simple three-level model of fluorescence.
It offers a convenient estimate of the order of magnitude of
irradiance required to observe significant photobleaching for a
uniform beam. In an effort to improve the application to MTV,
analytical formulas enable to determine the photobleached signal
strength from a Gaussian UV laser beam overlapping with a green laser
sheet and imaged from the side, as well as the apparent width of the
imaged photobleached line.
Controlling electronic and optical properties of zigzag graphene nanoribbons by a modulated electric field: significance of σ bands
Authors: Hieu Nguyen N. , Shih Po-Hsin , Hoi Bui D. , Do Thi-Nga , Nguyen Chuong V.
Published: June 2021

We investigate the peculiar electronic and optical properties of zigzag graphene nanoribbons (GNRs) under the effects of uniform and modulated electric fields. The hybridization between the four atomic orbitals (

s

,

p
x

,

p
y

,

p
z

) is considered by means of the tight-binding model calculations. Both the

π

bands originating from the

p
z

orbital and

σ

bands arising from the (

s

,

p
x

,

p
y

) orbitals play critical roles in the electronic structure and thus the absorption spectra. They determine the Fermi level and the available excitation channels between the occupied and unoccupied states. We show that an in-plane electric field in the form of modulated potential can significantly modify the electronic and optical properties of zigzag GNRs. The field-induced modification in energy dispersion, band-edge states, and band gap gives rise to rich absorption spectra with diverse structures. Our theoretical prediction could be verified by angle-resolved photoemission spectroscopies and optical spectroscopies.
Performance of a CsI(Tl) scintillation screen with a dual-periodic structure based on an oxidized silicon micropore array template in X-ray imaging
Authors: Sun Zhixiang , Gu Mu , Li Qianli , Liu Xiaolin , Liu Bo , Zhang Juannan , Huang Shiming , Ni Chen
Published: June 2021

To address the reduction in the detection efficiency of a structured CsI(Tl) scintillation screen when its structure period reaches the order of microns, a dual-periodic structure of the screen is proposed. The special feature of the dual structure is that each unit of the primary structure is divided equally into either four or nine square column-shaped scintillation sub-units. The sub-units are separated only by SiO2 layers to form a secondary structure. The results show that the performance of a dual-structure CsI(Tl) screen in X-ray imaging is much better than that of a corresponding single-structure screen.
Shortcut to study angular momentum transfer of harmonic generation in intense laser fields
Authors: Su Yingtong , Fang Kaimin , Zhnag Jingtao
Published: June 2021

High-order harmonics generated from atoms driven by counter-rotating two-color circularly (CRTC) polarized laser fields are studied in the frame of a quantum-field scattering theory. We use a pair of generalized phased Bessel (GPB) functions to describe the harmonic generation amplitude. The use of GPB functions allows us to define the phase of a harmonic channel accurately, by which we obtain the spin angular momentum conservation relation in a straightforward way. The known selection rule of harmonic order in the CRTC field is obtained concisely. Main features of the harmonic spectra are recovered. Our treatment provides a shortcut to study the angular momentum transfer in intense laser fields.
Optics metrology and at-wavelength wavefront characterization by a microfocus X-ray grating interferometer
Authors: Zhao Shuai , Yang Yu , Shen Yuan , Cheng Guangyu , Wang Yushan , Wang Qiuping , Zhang Lei , Wang Keyi
Published: June 2021

A microfocus X-ray grating interferometer (MFXGI) is proposed to measure the profile of the X-ray wavefront and slope error of X-ray optical elements. This device consists of a phase grating G1 to modulate the incoming wavefront and an absorption grating G2 as a transmission mask for the position-sensitive detector. The wavefront distortions caused by the deformable mirror were analyzed under operating conditions for in situ investigation of X-ray optical elements. The MFXGI can obtain direct and reflected beams in one recorded image at the same time through a microfocus X-ray source. The direct beam can be used to calculate the parameter errors and spherical shape for error compensation and retrieve the aspherical shape of the height profile. This instrument is expected to be a valuable tool for further technical progress in X-ray adaptive optics and X-ray mirror manufacturing and mounting.
Angular Airy function: a model of Fabry-Perot etalons illuminated by arbitrary beams
Authors: Marques Dylan M. , Guggenheim James A. , Munro Peter R. T.
Published: June 2021

Fabry-Perot (FP) etalons are used as filters and sensors in a range of optical systems. The reflected and transmitted fields associated with an FP etalon have traditionally been predicted by the Airy function, which assumes a plane wave illumination. FP etalons are, however, often illuminated by non-collimated beams, rendering the Airy function invalid. To address this limitation, we describe the angular Airy function which calculates the reflected and transmitted fields for arbitrary illumination beams, using angular spectrum decomposition. Combined with realistic models of the experimental illumination beams and detection optics, we show that the angular Airy function can accurately predict experimental wavelength resolved intensity measurements. Based on the angular Airy function, we show that the fundamental operating principle of an FP etalon is as an angular-spectral filter. Based on this interpretation we explain the asymmetry, broadening and visibility reduction seen on wavelength resolved intensity measurements from high Q-factor FP etalons illuminated with focused Gaussian beams.
Compression-coding-based surface measurement using a digital micromirror device and heterodyne interferometry of an optical frequency comb
Authors: Xu Guangyao , Wang Yue , Chen Jiayang , Xiong Shilin , Wu Guanhao
Published: June 2021

We propose a compression-coding-based surface measurement method that combines single-pixel imaging and heterodyne interference using an optical frequency comb. The real and imaginary parts of the heterodyne interference signals are used to obtain the depth information rapidly. By optimizing the ordering of the Hadamard measurement basis, we reconstruct a three-step sample with heights of approximately 10, 20, and 30 µm without an iterative operation in 6 ms, with a precision of 5 nm. Compared with the uncompressed measurement, the sampling times reduced to 20%, and the measurement time reduced by five times without measurement accuracy loss. The proposed method is effective for rapid measurements, particularly for objects with a simple surface topography.
Ultralow-loss fusion splicing between negative curvature hollow-core fibers and conventional SMFs with a reverse-tapering method
Authors: Wang Caoyuan , Yu Ruowei , Debord Benoît , Gérôme Frédéric , Benabid Fetah , Chiang Kin Seng , Xiao Limin
Published: June 2021

Negative curvature hollow-core fibers (NC-HCFs) can boost the excellent performance of HCFs in terms of propagation loss, nonlinearity, and latency, while retaining large core and delicate cladding structures, which makes them distinctly different from conventional fibers. Construction of low-loss all-fiber NC-HCF architecture with conventional single-mode fibers (SMFs) is important for various applications. Here we demonstrate an efficient and reliable fusion splicing method to achieve low-loss connection between a NC-HCF and a conventional SMF. By controlling the mode-field profile of the SMF with a two-step reverse-tapering method, we realize a record-low insertion loss of 0.88 dB for a SMF/NC-HCF/SMF chain at 1310 nm. Our method is simple, effective, and reliable, compared with those methods that rely on intermediate bridging elements, such as graded-index fibers, and can greatly facilitate the integration of NC-HCFs and promote more advanced applications with such fibers.
Combining time of flight and photometric stereo imaging for 3D reconstruction of discontinuous scenes
Authors: Le Francois Emma , Griffiths Alexander D. , McKendry Jonathan J. D. , Chen Haochang , Li David Day-Uei , Henderson Robert K. , Herrnsdorf Johannes , Dawson Martin D. , Strain Michael J.
Published: June 2021

Time of flight and photometric stereo are two three-dimensional (3D) imaging techniques with complementary properties, where the former can achieve depth accuracy in discontinuous scenes, and the latter can reconstruct surfaces of objects with fine depth details and high spatial resolution. In this work, we demonstrate the surface reconstruction of complex 3D fields with discontinuity between objects by combining the two imaging methods. Using commercial LEDs, a single-photon avalanche diode camera, and a mobile phone device, high resolution of surface reconstruction is achieved with a RMS error of 6% for an object auto-selected from a scene imaged at a distance of 50 cm.
Directly observing the skew angle of a Poynting vector in an OAM carrying beam via angular diffraction
Authors: Qiu Song , Ren Yuan , Liu Tong , Liu Zhengliang , Wang Chen , Ding You , Sha Qimeng , Wu Hao
Published: June 2021

A new, to the best of our knowledge, method for directly measuring the skew angle of a Poynting vector of optical vortices is reported in this Letter. We design an incomplete optical vortex phase to mimic the occlusion of actual objects on the light path. By capturing the intensity cross section of the incomplete vortex field, the energy flow can be observed directly; thus, the skew angle of the Poynting vector can be directly measured. In this Letter, we measure the skew angle of the Poynting vector with an error less than 3%. Further, the work in this Letter may provide a new way to sense the translational distance and measure the topological charge of the optical vortex.
Resistance exercise, alone and in combination with aerobic exercise, and obesity in Dallas, Texas, US: A prospective cohort study
Authors: Brellenthin Angelique G. , Lee Duck-chul , Bennie Jason A. , Sui Xuemei , Blair Steven N.
Published: June 2021

Background

Obesity is a significant and growing public health problem in high-income countries. Little is known about the relationship between resistance exercise (RE), alone and in combination with aerobic exercise (AE), and the risk of developing obesity. The purpose of this prospective cohort study was to examine the associations between different amounts and frequencies of RE, independent of AE, and incident obesity.

Methods and findings

Participants were 11,938 healthy adults ages 18–89 years with a BMI < 30 kg/m2at baseline who completed at least 2 clinical examinations during 1987–2005 as part of the Aerobics Center Longitudinal Study. Self-reported RE participation in minutes/week and days/week was collected from a standardized questionnaire. Incident obesity was defined as a BMI ≥ 30 kg/m2at follow-up. Incident obesity was also defined by waist circumference (WC) > 102/88 cm for men/women and percent body fat (PBF) ≥ 25%/30% for men/women at follow-up in participants who were not obese by WC (n =9,490) or PBF (n =8,733) at baseline. During the average 6-year follow-up, 874 (7%), 726 (8%), and 1,683 (19%) developed obesity defined by BMI, WC, or PBF, respectively. Compared with no RE, 60–119 min/wk of RE was associated with 30%, 41%, and 31% reduced risk of obesity defined by BMI (hazard ratio [95% CI], 0.70 [0.54–0.92],p= 0.008), WC (0.59 [0.44–0.81],p <0.001), and PBF (0.69 [0.57–0.83],p <0.001), respectively, after adjusting for confounders including age, sex, examination year, smoking status, heavy alcohol consumption, hypertension, hypercholesterolemia, diabetes, and AE. Compared with not meeting the RE guidelines of ≥2 d/wk, meeting the RE guidelines was associated with 18%, 30%, and 30% reduced risk of obesity defined by BMI (hazard ratio [95% CI], 0.82 [0.69–0.97],p= 0.02), WC (0.70 [0.57–0.85],p <0.001), and PBF (0.70 [0.62–0.79],p <0.001), respectively. Compared with meeting neither guideline, meeting both the AE and RE guidelines was associated with the smallest hazard ratios for obesity. Limitations of this study include limited generalizability as participants were predominantly white men from middle to upper socioeconomic strata, use of self-reported RE, and lack of detailed diet data for the majority of participants.

Conclusions

In this study, we observed that RE was associated with a significantly reduced risk of obesity even after considering AE. However, meeting both the RE and AE guidelines was associated with the lowest risk of obesity.
A 3D basicranial shape-based assessment of local and continental northwest European ancestry among 5th to 9th century CE Anglo-Saxons
Authors: Plomp Kimberly A. , Dobney Keith , Collard Mark
Published: June 2021

The settlement of Great Britain by Germanic-speaking people from continental northwest Europe in the Early Medieval period (early 5thto mid 11thcenturies CE) has long been recognised as an important event, but uncertainty remains about the number of settlers and the nature of their relationship with the preexisting inhabitants of the island. In the study reported here, we sought to shed light on these issues by using 3D shape analysis techniques to compare the cranial bases of Anglo-Saxon skeletons to those of skeletons from Great Britain that pre-date the Early Medieval period and skeletons from Denmark that date to the Iron Age. Analyses that focused on Early Anglo-Saxon skeletons indicated that between two-thirds and three-quarters of Anglo-Saxon individuals were of continental northwest Europe ancestry, while between a quarter and one-third were of local ancestry. In contrast, analyses that focused on Middle Anglo-Saxon skeletons suggested that 50–70% were of local ancestry, while 30–50% were of continental northwest Europe ancestry. Our study suggests, therefore, that ancestry in Early Medieval Britain was similar to what it is today—mixed and mutable.
A spatially explicit model for estimating risks of pesticide exposure to bird populations
Authors: Etterson Matthew , Schumaker Nathan , Garber Kristina , Lennartz Steven , Kanarek Andrew , Connolly Jennifer
Published: June 2021

Pesticides are used widely in agriculture and have the potential to affect non-target organisms, including birds. We developed an integrated modeling system to allow for spatially-explicit evaluation of potential impacts to bird populations following exposures to pesticides. Our novel methodology builds upon three existing models: the Terrestrial Investigation Model (TIM), the Markov Chain Nest Productivity Model (MCnest), and HexSim to simulate population dynamics. We parameterized the integrated modeling system using information required under the Federal Insecticide, Fungicide, and Rodenticide Act, together with species habitat and life history data available from the scientific literature as well as landcover data representing agricultural areas and species habitat. Our case study of the federally threatened California Gnatcatcher (Polioptila californica) illustrates how the integrated modeling system can estimate the population-scale consequences of pesticide applications. We simulated impacts from two insecticides applied to wheat: one causing mortality (survival stressor), and the other causing reproductive failure (reproductive stressor). We observed declines in simulated gnatcatcher abundance and changes in the species’ distribution following applications of each pesticide; however, the impacts of the two pesticides were different. Our methodology attempts to strike a balance between biological realism and model complexity and should be applicable to a wide array of species, systems, and stressors.
Wound healing with topical BRAF inhibitor therapy in a diabetic model suggests tissue regenerative effects
Authors: Escuin-Ordinas Helena , Liu Yining , Sun Lu , Hugo Willy , Dimatteo Robert , Huang Rong Rong , Krystofinski Paige , Azhdam Ariel , Lee Jordan , Comin-Anduix Begoña , Cochran Alistair J. , Lo Roger S. , Segura Tatiana , Scumpia Philip O. , Ribas Antoni
Published: June 2021

Wound healing is a multi-step process to rapidly restore the barrier function. This process is often impaired in diabetic patients resulting in chronic wounds and amputation. We previously found that paradoxical activation of the mitogen-activated protein kinase (MAPK) pathway via topical administration of the BRAF inhibitor vemurafenib accelerates wound healing by activating keratinocyte proliferation and reepithelialization pathways in healthy mice. Herein, we investigated whether this wound healing acceleration also occurs in impaired diabetic wounds and found that topical vemurafenib not only improves wound healing in a murine diabetic wound model but unexpectedly promotes hair follicle regeneration. Hair follicles expressing Sox-9 and K15 surrounded by CD34+ stroma were found in wounds of diabetic and non-diabetic mice, and their formation can be prevented by blocking downstream MEK signaling. Thus, topically applied BRAF inhibitors may accelerate wound healing, and promote the restoration of improved skin architecture in both normal and impaired wounds.
Attitude and behavior toward bystander cardiopulmonary resuscitation during COVID-19 outbreak
Authors: Chong Kah-Meng , Chen Jiun-Wei , Lien Wan-Ching , Yang Mei-Fen , Wang Hui-Chih , Liu Sot Shih-Hung , Chen Yen-Pin , Chi Chien-Yu , Wu Marvin Chih-Hsien , Wu Cheng-Yi , Liao Edward Che-Wei , Huang Edward Pei-Chuan , He Hsien-Chin , Yang Hsiang-Wen , Huang Chien-Hua , Ko Patrick Chow-In
Published: June 2021

Background

Outbreaks of emerging infectious diseases, such as COVID-19, have negative impacts on bystander cardiopulmonary resuscitation (BCPR) for fear of transmission while breaking social distancing rules. The latest guidelines recommend hands-only cardiopulmonary resuscitation (CPR) and facemask use. However, public willingness in this setup remains unknown.

Methods

A cross-sectional, unrestricted volunteer Internet survey was conducted to assess individuals’ attitudes and behaviors toward performing BCPR, pre-existing CPR training, occupational identity, age group, and gender. The raking method for weights and a regression analysis for the predictors of willingness were performed.

Results

Among 1,347 eligible respondents, 822 (61%) had negative attitudes toward performing BCPR. Healthcare providers (HCPs) and those with pre-existing CPR training had fewer negative attitudes (p < 0.001); HCPs and those with pre-existing CPR training and unchanged attitude showed more positive behaviors toward BCPR (p < 0.001). Further, 9.7% of the respondents would absolutely refuse to perform BCPR. In contrast, 16.9% would perform BCPR directly despite the outbreak. Approximately 9.9% would perform it if they were instructed, 23.5%, if they wore facemasks, and 40.1%, if they were to perform hands-only CPR. Interestingly, among the 822 respondents with negative attitudes, over 85% still tended to perform BCPR in the abovementioned situations. The weighted analysis showed similar results. The adjusted predictors for lower negative attitudes toward BCPR were younger age, being a man, and being an HCP; those for more positive behaviors were younger age and being an HCP.

Conclusions

Outbreaks of emerging infectious diseases, such as COVID-19, have negative impacts on attitudes and behaviors toward BCPR. Younger individuals, men, HCPs, and those with pre-existing CPR training tended to show fewer negative attitudes and behaviors. Meanwhile, most individuals with negative attitudes still expressed positive behaviors under safer measures such as facemask protection, hands-only CPR, and available dispatch instructions.
Physical contact transmission of Cucumber green mottle mosaic virus by Myzus persicae
Authors: Qi Yu-Hua , He Yu-Juan , Wang Xin , Zhang Chuan-Xi , Chen Jian-Ping , Lu Gang , Li Jun-Min
Published: June 2021

Cucumber green mottle mosaic virus (CGMMV), a critical plant virus, has caused significant economic losses in cucurbit crops worldwide. It has not been proved that CGMMV can be transmitted by an insect vector. In this study, the physical contact transmission of CGMMV by Myzus persicae in Nicotiana benthamiana plants was confirmed under laboratory conditions. The acquisition rate increased with time, and most aphids acquired CGMMV at 72 h of the acquisition access period (AAP). Besides, the acquired CGMMV was retained in the aphids for about 12 h, which was efficiently transmitted back to the healthy N. benthamiana plants. More importantly, further experiments suggested that the transmission was mediated by physical contact rather than the specific interaction between insect vector and plant virus. The results obtained in our study contribute to the development of new control strategies for CGMMV in the field.