bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the Effects of Low-Dose Radiation on Human Mesenchymal Stem Cells
Authors: Usupzhanova D. , Astrelina T. , Kobzeva I. , Nikitina V. , Suchkova Yu. , Brunchukov V. , Rastorgueva A. , Brumberg V. , Bushmanov A. , Samoylov A.
Published: April 2021

Purpose: The aim of the study was to study the effect of low X-ray doses on human mesenchymal stem cells (MSCs) in long-term cultivation in vitro.

Material and methods: MSCs of the mucosal gum tissue of human were used. Cells were irradiated using an RUST-M1 X-ray unit (Russia) at doses of 50, 80, 100, 250 and 1000 mGy (dose rate40 mGy/min) and then cultivated according to standard methods. Immunological characteristics and viability of MSCs were evaluated on a FACSCanto II flow cytometer (Becton Dickinson CA, USA) for early and late passengers. Proliferative activity (PA) was evaluated using an xCelligence real-time cell analyzer (ACEA Biosciencs, Inc.).

Results: It was shown that the proliferative activity (PA) of MSCs of the mucosal gum tissue which were irradiated at dose 50 mGy is comparable with the control group in long-term cultivation while doses of 100 and 250 mGy showed a decrease of PA. Also non-irradiated MSCs showed a significant decrease of the PA during cultivation in a conditioned medium from cells that received dose of 1000 mGy and an increase of PA during cultivation in a conditioned medium of cells that received doses of 50, 100 and 250 mGy. The cells were previously irradiated at dose 250 mGy showed adaptive response during cultivation in conditioned medium from cells that received dose of 1000 mGy.

Сonclusion: The assessment of the effects of low radiation doses was focused on the bystander effect in the presented study. It was noted after adding conditioned media from irradiated cells to previously irradiated and non-irradiated MSCs. The bystander effects for low and high doses are different and their biological meaning requires further study. The phenomenon of adaptive response was shown after addition conditioned media from cells irradiated at dose 1000 mGy to pre-irradiated MSCs received a dose of 250 mGy. The obtained result leads to the conclusion that the effects of low doses can be positive. Thus, the results of study mainly correspond to the threshold nonlinear concept, according to which the effect is not proportional to the received radiation dose.
ANALISIS SIKAP KONSUMEN PADA RUMAH SAKIT UMUM PKU MUHAMMADIYAH YOGYAKARTA
Authors: Anhari Agus , Setyono Hendro
Published: April 2021

Selective community in selecting health care must be observed and analyzed hospital. Hospital as a place to obtain medical services necessary to meet the expectations of society, as a subscription service (consumer) health. Hospitals need to know the ratio of users to health services that are more selective. Or not the positive attitude of consumers ideally clear from evaluation and their trust in the services they receive. Improved elements (attributes), such as tenderness, attention, safety and reliability of direct evidence is absolutely necessary as a measure of quality of service in the services sector.This study aims to determine consumer attitudes and the relationship between consumer confidence with consumer ratings on General Hospital PKU Muhammadiyah Yogyakarta. consumer attitudes referred to in this research is the level of feelings of patients in comparing the performance (results) are perceived with hope. So the attitude of patients is a function of the difference between the perceived performance with expectations.Consumer Attitudes towards the General Hospital of PKU Muhammadiyah Yogyakarta at 80.03 and is located in the interval from 77 to 100.9 and included in the positive category. While the relationship between assessment and the resulting consumer confidence coefficient = 0.072, ρ = 0.000 and α of 0.01 for ρ sig (0.000) < α of 0.01, it can be concluded that there is a strong relationship between consumer confidence with consumers ranking House PKU Muhammadiyah Hospital in Yogyakarta.
FAKTOR-FAKTOR YANG MEMPENGARUHI STRUKTUR MODAL PADA PERUSAHAAN TELEKOMUNIKASI DI INDONESIA
Authors: Sukmaningtyas Jantu , Asakdiyah Salamatun
Published: April 2021

The purpose of this thesis is to analyze factors that influence capital structure at telecommunications industry in Indonesia. In this research, dependent variable is capital structure and the independent variables are the operating leverage, taxes, and firm size.The samples are 5 companies, its take by purposive sampling method: taking the sample with specific criteria, that is the companies which listed on the Indonesia Stock Exchange during the period from 2005 to 2009. The operating leverage has a positive and significant influence to capital structure, tax has a negative and significant impact to capital structure, but the variable firm size has no effect to capital structure.
ANALISIS PENGARUH ATRIBUT PRODUK DAN ATRIBUT IKLAN TERHADAP MOTIVASI PEMBELIAN SEPEDA MOTOR HONDA VARIO
Authors: Luthfiah Nur Fitri , Asakdiyah Salamatun
Published: April 2021

The purpose of this study was to find out product attributes effect and attribute motivation to purchase ads on Honda Vario. The population in this study are all citizens of district Pandak ever bought and used Honda Vario. Sampling technique using purposive sampling. Characteristics of sampled respondents who are residents of districts Pandak ever bought and used Honda Vario motorcycles 17 year old and over. The data was collected by distributing questionaires to a sample of the 100 people. Based on the analysis by t-test of the product attribute variables (X1) obtained the result of probability (0.007), and attribute variables (X2) obtained the probability (0.0001) with significantly the level of 5% (0.05). the probability of two independent variables are smaller than the significance level of 0.05. So based on that analysis can be concluded that the product attributes and attribute partially ads have a significant influence on purchase motivation Honda Vario.
ANALISIS KINERJA KEUANGAN PERUSAHAAN PENGAKUSISI SEBELUM DAN SESUDAH MERGER AKUISISI YANG TERDAFTAR DI BURSA EFEK INDONESIA
Authors: Navisah Navisah , Asakdiyah Salamatun
Published: April 2021

The purpose of this study was to analyze whether there is a difference in financial performance (measured by the Current Ratio, Debt to Equity Ratio, Debt to Total Assets Ratio, Total Assets Turn Over, Return on Investment and Net Profit Margin) the acquire in 2 years before and 2 years after merger acquisition. Grouping of the population being sampled is done non-probability conducted by the method of “purposive sampling” and acquired 13 companies the sample population of 19 companies. Analysis of the measured data of different test receipts, before going to the normality test analyzed the data, if the data are not normally distributed then analysis used in this study is a Paired Sample t-test, and if the data are not normally distributed then testing using the Wilcoxon Signed Rank Test using a significance level of 0.05. Test results using paired sample t-test showed that financial performance is measured by analysis of the Current Ratio, Total Asset Turn Over, Return on Investment and Net Profit Margin there is no difference, while for financial performance as measured by analysis of Debt to Total Assets Ratio indicates there financial performance difference between the 2 years before and 2 years post-merger acquisition. Then testing using the Wilcoxon Signed Rank Test showed no difference in financial performance as measured by Debt to Equity Ratio analysis in the 2 years before and after the merger acquisitions.
ANALISIS CAPITAL ADEQUANCY RATIO (CAR), LOAN TO DEPOSIT RATIO (LDR), DAN RETURN ON ASSETS (ROA) TERHADAP TINGKAT SUKU BUNGA DEPOSITO BERJANGKA PADA BANK BUMN PERIODE 2009-2014
Authors: Suratama Isna Nurcahyani , Fitriani Dyah
Published: April 2021

This study aims to determine the effect of Capital Adequacy Ratio (CAR), Loan to Deposit Ratio (LDR) and Return on Assets (ROA) on the interest rate for time deposits at state-owned banks in Indonesia in the 2009-2014 period. The sample used in this study is state-owned banks in Indonesia, as many as 4 banks. The sampling technique used was purposive sampling technique. The method used in this study is quantitative research and the data obtained are secondary data where the data is already available in report form. The analysis technique used is multiple linear regression, hypothesis testing (t test and F test) and the coefficient of determination test. The results of the analysis showed that partially the Capital Adequacy Ratio (CAR) showed a regression coefficient of -0.674775 with a prob value of 0.5915, which meant that the CAR had a negative and not significant effect on deposit rates, while the Loan to Deposit Ratio (LDR) showed a value of regression coefficient of 0.109967 with a value of prob. 0.6871 which means that the LDR has a positive and not significant effect on the interest rate on time deposits and Return on Assets (ROA) shows a value of -10,63718 with a prob. 0.4255 which means ROA has a negative and not significant effect on the interest rate on time deposits. Based on the F test shows a prob value of 0.300476 so that simultaneously, CAR, LDR and ROA have no significant effect on the interest rate on time deposits.
ANALISIS ANTESEDEN YANG MEMPENGARUHI NIAT BELI ON-LINE PADA TOKOPEDIA.COM
Authors: Rokhim Nur , Adhilla Fitroh
Published: April 2021

This research was conducted to examine the antecedents that affect online purchase intentions. The sample used in this study amounted to 71 respondents. The sampling method using purposive sampling. Data analysis method used is quantitative analysis using validity and reliability tests, F tests, coefficient of determination, t tests and multiple regression analysis. By using the multiple regression method it can be concluded that the web design variable does not have a positive and significant effect on online purchase intention with a significance value (P Value) of 0.324> 0.05. While reliability has a positive and significant effect on online purchase intentions with a significance value (P Value) of 0.018 <0.05. responsiveness has a positive and significant effect on online purchase intentions with a significance value (PValue) of 0.061> 0.05. The guarantee has a positive and significant effect on online purchase intention with a significance value (P Value) of 0.815> 0.05. For ordering a positive and significant effect on online purchase intentions with a significance value (P Value) of 0, 002 <0.05. Simultaneously web design, reliability, responsiveness, guarantee, and ordering have a significant effect on online purchase intention with an F count of 5.960 with a significance value (P Value) of 0.000 <0.05. The resulting determination coefficient is 0.246, which means that 24.6 percent of changes in the online purchase intention variable are explained by changes in web design variables, reliability, responsiveness, guarantees, and bookings together, while the remaining 76.4 percent is explained by other variables which is not included in this study.
PENGARUH KOMPENSASI, MOTIVASI, DAN PELATIHAN KERJA TERHADAP KINERJA KARYAWAN ATAU PEGAWAI DINAS PERTANIAN DAERAH ISTIMEWA YOGYAKARTA
Authors: Rohman Abdul , Bidayati Utik
Published: April 2021

This study aims to determine whether compensation, motivation and job training affect the performance of employees or service employees Yogyakarta Special Region Agriculture and analyze the influential factors and has no effect on the performance of employees or employees of the Department of Agriculture Special Region of Yogyakarta. The sample in this study were employees or Dinas employees Yogyakarta Special Region of Agriculture. 84 samples were processed respondent. The sampling technique uses sampling purposive, the number of samples obtained was 84 respondents, i.e. sampling techniques with certain considerations. Considerations in this research is a permanent employee. Based on the results of statistical data analysis, the indicators of the study this is valid and the variables are reliable. Order individually from each of the most influential variables is the training variablework with a t test value of 3.758, then compensation with a t test value of 2,309. Then the variable that has no effect is the motivation variable with a t test value of -0.826. Yogyakarta Special Region Government needs maintain elements that have been assessed as good as giving Work compensation and training, and those with less influence need to be evaluated back to work motivation. The amount of influence caused (R2) by these three variables together to the bound of 0.229 or 22.9%, while the remaining 0.771 or 77.1% is influenced by other variables not examined in this study.
PENGARUH RETAIL MIX TERHADAP KEPUTUSAN PEMBELIAN KONSUMEN DI DM BARU SWALAYAN BANTUL
Authors: Analde Iddam Restu , Sukardi Sukardi
Published: April 2021

This study aims to determine (1) whether there is a retail effect mix (Product Diversity, Store Location, Pricing, Consumer Services, Store Design and Display, and Communication Mix) on purchasing decisions consumers in DM Baru Swalayan Bantul both partially and simultaneously. The object in this study is DM Baru Swalayan Bantul. This research was conducted by distributing questionnaires to 100 respondents are DM Baru Swalayan consumers who have shopped at least 2x (twice) in March and April. Analyzer used to measure the effect of Retail Mix on purchasing decisions is linear regression analysis multiple. Based on the results of the research variable Product Diversity, Store Location, Pricing, Consumer Services, Store Design and Display, and Communication Mix effect simultaneously, this is indicated by the value significance less than 0.05 is 0,000. While the variables are partial effect is the customer service variable (X4) with value significance 0.004 <0.05 and the Communication Mix variable (X6) with values significance of 0.009 < 0.05.
PENGARUH RISIKO KREDIT, MINIMALISASI RISIKO, PERTUMBUHAN PRODUK DOMESTIK BRUTO, DAN INFLASI TERHADAP PENDAPATAN BUNGA BERSIH PADA PERUSAHAAN PERBANKAN YANG TERDAFTAR DI BURSA EFEK INDONESIA PERIODE 2013-2016
Authors: Widyawati Devi , Kusuma Desta Rizky
Published: April 2021

The aim of this research is to examine empirically the impact of credit risk, risk aversion, gross domestic product (GDP) growth, and inflation to Net Interest Margin on banking companies enlisted in BEI year 2013-2016. The factors that influenced NIM is credit risk which is proxied with NPL (Non Performing Loan) ratio, risk aversion which is proxied with CAR (Capital Adequacy Ratio), GDP growth and inflation. The period used is from 2013-2016.This research is causal research, that is to find recausality of independent and dependent variable. The population is 42 banking companies. The sampling method used is purposive sampling method. Based on the criteria, there are 41 banking companies. The hypothesis trial is done by the analysis of data panel regression an before do it, the research did a classic assumption trial. The result of hypothesis trial is done partially is t-test showed that NPL has t-statistic score is 1,4136 and t-tabel score is 1,290 on alpha 10% , so NPL has positive impact to NIM. CAR has t-statistic score is -0,2698 and t-tabel score is 1,290 on alpha 10%, so CAR doesn’t have impact to NIM. GDP growth has t-statistic score is 2,9349 and t-tabel score has 1,290 on alpha 10%, so GDP growth has positive impact to NIM. Inflation has t-statistic -0,5184 and t-tabel score is 1,290 on alpha 10%, so inflation doesn’t have impact to NIM.
PENGARUH KUALITAS PRODUK, HARGA, DAN GETOK TULAR TERHADAP KEPUTUSAN PEMBELIAN PRODUK PADA TOKO PD. PESAGI JAYA TANI DI SEKINCAU LAMPUNG BARAT
Authors: Gumelar A. Deny Sekti , Adhilla Fitroh
Published: April 2021

This study aims to analyze the effect of product quality, prices, and infectiousness to the purchasing decision at PD Pesagi jaya farmers in West Lampung Sekincau. In this study the population used is a customer who once bought at a PD Pesagi glorious farmer. Based on the results of questionnaire data analysis of 60 customer respondents who once bought at a PD Pesagi glorious farmer using techniques non probability sampling which is a technique that does not provide opportunities or equal opportunity for each element or member of the population to be elected be sampled using purposive sampling, test instruments use validity and reliability test analysis, analysis tools with using multiple regression, hypothesis testing through t test and F test, as well as analysis of the coefficient of determination (R2). Hypothesis testing using the t test shows that three variables independent studied are the variables of product quality, price, and infectiousness proven to have a positive and significant effect on the dependent variable, i.e buying decision. Then through the F test can be seen that the third independent variables are feasible to test the dependent variable decision the purchase.
PENGARUH CURRENT RATIO, DEBT TO EQUITY RATIO, DAN NET PROFIT MARGIN TERHADAP RETURN SAHAM PADA PERUSAHAAN KOSMETIK DAN BARANG KEPERLUAN RUMAH TANGGA YANG TERDAFTAR DI BURSA EFEK INDONESIA PERIODE 2012-2017
Authors: Fatansiru Nalindri Arin , Merdiana Candra Vionela
Published: April 2021

This study aims to analyze the effect of Current Ratio, Debt toEquity Ratio, and Net Profit Margin on stock returns of case studies in companies cosmetics and household goods listed on the Indonesia Stock Exchange period 2012-2017 Independent variables used in this study are Current Ratio, Debt to Equity Ratio, and Net Profit Margin while the dependent variable is stock returns. The population in this study is all cosmetics and household goods companies for the period 2012-2017. Based on the purposive sampling method obtained 5 samples. Data type used is secondary data. Data obtained by the method of documentation. The analysis technique used is the Panel Data Regression Analysis. The results of multiple linear regression analysis with a significant level of 5%, then it can concluded that the first hypothesis Current Ratio of 0.02 has a negative effect and significant towards stock returns, the second hypothesis is Debt to Equity Ratio of 0.90 positive and not significant effect on stock returns, the third hypothesis is Net Profit Margin of 0.08 has no effect on stock returns, hypotheses fourth, Current Ratio, Debt to Equity Ratio, and Net Profit Margin of 0.015726 simultaneously affect stock returns.
ANALISIS PENGARUH KEBIJAKAN HUTANG TERHADAP KINERJA KEUANGAN
Authors: Wijaya Ari Triadi , Fikri Muhammad Ali
Published: April 2021

This study aims to determine the effect of debt policy on  financial performance of coal companies listed on the Indonesia Stock Exchange. Policy debt is proxied by short term debt (STD), long term debt (LTD), and total debt (TD), while financial performance is proxied by return on equity (ROE). This research carried out for 3 (three) years, namely 2015-2017. This research is a causal research with a quantitative approach, whereas based on the level of exploration of this study, including associative research. Population research is a coal company listed on the Indonesia Stock Exchange for the period 2015-2017. Samples obtained were based on purposive sampling technique, and obtained 21 company. Data analysis technique used panel data regression. Regression with using the free variable short term debt (STD), long term debt (LTD), and total debt (TD). Based on the results of data analysis, STD has no significant effect on ROE. Variable LTD has a significant effect on ROE. The TD variable has no significant effect with ROE. so the STD and LTD variables are able to influence the ROE variable explained by other factors outside this research model.
The Determinant Factors of Muzakki Toward Paying Zakat, Infaq, Sedekah (ZIS) in Zakat Institutions
Authors: Hapsari Hening Pratika Nila , Priyadi Unggul
Published: April 2021

Introductions to The Problem: Zakat is one of worship which is often mentioned in the Al Quran. It's just that the potential for Zakat, Infaq, Alms (ZIS) is not comparable to the actual actual figures. Many factors influence muzakki in paying ZIS.Purpose/Objective Study: This study aims to analyze the factors that influence muzakki to pay ZIS in zakat institutions, namely Yatim MandiriDesign/ Methodology/ Approach: The sample in this study amounted to 200 respondents. LAZ Yatim Mandiri was chosen because it is an Amil Zakat Institution that is consistent in collecting ZIS funds from the smallest amount to the large amount. This study uses logistic regression analysis and the data used are primary data. Based on the analysis that has been done, it is found that 61% results can be predicted correctly in the logistic regression model in this study.Findings: The consistency of muzakki in paying ZIS at the Yatim Mandiri Amil Zakat Institution is influenced by the variables of religiosity, income, trust, shariah compliance, knowledge, justice, data publication, financial accountability, motivation, the role of ulama, the role of government. And the consistency of muzakki in paying ZIS at the Yatim Mandiri Amil Zakat Institution is not influenced by the variables of shariah compliance and financial accountability.
Self-reported quality of activities of daily living task performance in four diagnostic groups with chronic conditions
Authors: Nielsen Kristina Tomra , Klokker Louise , Wæhrens Eva Ejlersen
Published: April 2021

Background/aims

To design intervention programmes addressing activities of daily living task performance problems in individuals with chronic conditions, more knowledge about the types of challenges these individuals experience is needed. The aim of this study was to examine the types of activities of daily living tasks, as well as the types of problems related to the quality of task performance, that individuals with chronic conditions report and determine similarities and differences in four diagnostic sub-groups.

Methods

Data on self-reported quality of activities of daily living task performance were collected among 593 individuals with rheumatological disease, incurable cancer, chronic obstructive pulmonary disease and schizophrenia, using the ADL-Interview. Activities of daily living tasks most frequently reported as problematic were identified within each sub-group. Sub-group profiles were generated to identify similarities and differences in quality of performance.

Results

Participants reported problems performing similar types of activities of daily living tasks across diagnostic sub-groups, especially within instrumental activities of daily living. Moreover, participants mainly reported a decreased quality of performance in terms of using extra time and/or increased physical effort while performing personal activities of daily living.

Conclusions

As individuals across four chronic conditions reported somewhat similar problems related to activities of daily living task performance, generic activities of daily living interventions addressing these problems seem appropriate, especially interventions addressing problems related to use of extra time and increased effort.
Numerical simulation of all-optical logic gates based on hybrid-cavity semiconductor lasers
Authors: Liu Jia-Chen , Huang Yong-Zhen , Wang Fu-Li , Hao You-Zeng , Ma Chun-Guang , Yang Ke , Yang Yue-De , Xiao Jin-Long
Published: April 2021

All-optical switch and multiple logic gates have been demonstrated using a hybrid-cavity semiconductor laser composed of a square microcavity and a Fabry–Perot cavity experimentally. In this paper, two-section tri-mode rate equations with optical injection terms are proposed and applied to study all-optical logic gates of NOT, NOR, and NAND operations utilizing the hybrid-cavity laser. Steady-state and dynamical characteristics of all-optical multiple logic gates are simulated, taking into account the influence of mode frequency detuning, gain suppression coefficients, mode Q factor, injection energy, and biasing current. All-optical logic NOT, NOR, and NAND gates up to 20, 15, and 20 Gbit/s are obtained numerically with dynamic extinction ratios of over 20, 20, and 10 dB, respectively, which are potential response speeds of the all-optical logic gates based on the hybrid-cavity semiconductor lasers.
Ab initio theory of the Drude plasma frequency
Authors: Mendoza Bernardo S. , Mochán W. Luis
Published: April 2021

We derive a theoretical expression to calculate the Drude plasma frequency

ω
D

based on quantum mechanical time-dependent perturbation theory in the long-wavelength regime. We show that, in general,

ω
D
2

should be replaced by a second-rank tensor, the Drude tensor

D

, which we relate to the integral over the Fermi surface of the convective momentum flux tensor divided by the magnitude of the Fermi velocity and which is amiable to analytical and numerical evaluation. We also obtain an expression in terms of the average inverse mass tensor. For Sommerfeld’s model of metals, our expression yields the ubiquitous plasma frequency

ω
D
2

=
4
π

n
e

e
2

/

m
e

. We compare our expressions with those of previous theories. The Drude tensor takes into account the geometry of the unit cell and may be calculated from first principles for isotropic as well as anisotropic metallic systems. We present results for the noble metals Ag, Cu, and Au without stress and subject to isotropic and uniaxial strains; we also compare the results with those available from experiments. We show that, within density functional theory, nonlocal potentials are necessary to obtain an accurate Drude tensor.
Wide range thermal and athermal operation of slotted surface grating lasers
Authors: Mickus Dovydas , Mckenna Robert , Murphy Caolan , Donegan John F.
Published: April 2021

Athermalisation is a procedure in which the wavelength of a semiconductor laser remains unchanged even as the temperature is altered. This is achieved by altering the currents that flow through the laser so as to maintain the wavelength and avoid mode hops. In this study, we demonstrate that lasers operating with a large red-shift with respect to the gain peak yield the best performance in terms of the highest temperature operation and also in terms of the widest athermal operating range. In particular, a device with red detuning of approximately 25 nm yields the best results. This device is athermalised continuously (without mode hops) from 5 to 106
o
C, and discontinuously to 115
o
C while maintaining wavelength stability of

±

0.4 GHz/0.003 nm and side mode suppression ratio of above 40 dB in most of the continuous range and above 30 dB in the discontinuous regime. Operating in this manner will enable semiconductor lasers to be used without a thermoelectric cooler in applications where the temperature changes substantially.
Intensity-dependent angular distribution of low-energy electrons generated by intense high-frequency laser pulse
Authors: Liang Jintai , Jiang Weichao , Liao Yijie , Ke Qinghua , Yu Miao , Li Min , Zhou Yueming , Lu Peixiang
Published: April 2021

By solving the three-dimensional time-dependent Schrödinger equation, we investigate the angular distributions of the low-energy electrons when an intense high-frequency laser pulse is applied to the hydrogen atom. Our numerical results show that the angular distributions of the low-energy electrons which generated by the nonadiabatic transitions sensitively depend on the laser intensity. The angular distributions evolve from a two-lobe to a four-lobe structure as the laser intensity increases. By analyzing nonadiabatic process in the Kramers-Henneberger frame, we illustrate that this phenomenon is attributed to the intensity-dependent adiabatic evolution of the ground state wavefunction. When the laser intensity further increases, the pathway of nonadiabatic transition from the ground state to the excited state and then to the continuum states is non-negligible, which results in the ring-like structure in the photoelectron momentum distribution. The angular distributions of the low-energy electrons provide a way to monitor the evolution of the electron wavefunction in the intense high frequency laser fields.
Phase-change metasurface with tunable and switchable circular dichroism
Authors: Ding Chuanchuan , Rui Guanghao , Gu Bing , Zhan Qiwen , Cui Yiping
Published: April 2021

Metasurfaces with tunable/switchable circular dichroism (CD) response have great potential to serve as important elements for plenty of advanced applications. In this work, we proposed a novel metasurface absorber integrated with periodic

G
e

2

S
b

2

T
e

5

(GST) resonators and numerically demonstrated its capability in reconfiguration of the CD effect. Due to the strong chiral plasmonic resonance, a strong CD of about 0.75 can be achieved in a prescribed spectrum. Additionally, the phase transition of GST resonators enables the quasi-linearly modification of CD strength in a broad range (from 0.03 to 0.75). Furthermore, reversible chirality of the metasurface absorber can be realized by controlling the states of the left- and right-hand GST resonators separately, enabling the CD signal to be readily switched between on-, off-, and reverse-state.
Influence of different concentrations of SbCl3 salt on the properties of Sb2S3 nanobars prepared by the solvothermal method for solar cell application
Authors: Mkawi E. M. , Almalki Rahma , Al-Hadeethi Y.
Published: April 2021

Antimony sulfide (Sb2S3) nanobars are synthesized by the solvothermal method using different concentrations of the antimony chloride salt (SbCl3)at 180 °C for 14 h. The effects of 0.75, 0.8, 0.85, and 0.9 mmol of SbCl3 on the compositions, morphologies, and phases of the product are investigated. Raman spectroscopy indicates that the product corresponds to the pure orthorhombic phase of Sb2S3. Transmission electron microscopy indicates that the appearance of the as-synthesized Sb2S3 resembles that of nanobars with a typical width of 200–300 nm, which predominantly grow along the [001] direction. Chemical composition analysis confirms that the sample is composed of S and Sb, and the atomic ratio of Sb/S is close to 2:3, which is confirmed by X-ray photoelectron spectroscopy. The phase-pure Sb2S3 nanobars exhibit an optical energy gap between 1.5 eV and 1.74 eV and an absorption coefficient of approximately 104 cm−1, which would thus be suitable for use in photovoltaic applications. Scanning electron microscopy results indicate that the Sb2S3 thin-film-based nanobars are compact and smooth with a grain size of more than 3 µm. The best results reported here are for the solar cell structure Mo/Sb2S3/CdS/ITO/Ag with an open circuit voltage of 451 mV, short circuit current density of 12.47 mA/cm2, fill factor of 0.61, and conversion efficiency of 3.46%.
All-fiber passively mode-locked laser based on an electron beam evaporation grown Co2+:ZnSe film saturable absorber
Authors: Wu Zhujing , Dai Jiangyun , Wu Yajie , Yang Jiulin , Zhang Hong , Zhou Shouhuan
Published: April 2021

We experimentally demonstrated an all-fiber mode-locked erbium-doped laser based on Co2+:ZnSe (Cobalt, Zinc Selenide) thin film as the saturable absorber (SA), which was grown on the fiber taper by electron beam (e-beam) evaporation technology. The modulation depth, non-saturable loss and saturation intensity were found to be ∼12%, 76% and 1.89 MW/cm2, respectively. The X ray diffraction (XRD) results showed that the Co2+:ZnSe thin film was provided with the cubic zinc blende structure. The scanning electron microscope (SEM) and atomic force microscopy (AFM) images showed the prepared thin film has a smooth and uniform surface. When the fiber-taper Co2+:ZnSe SA was inserted into an erbium-doped fiber laser cavity, a stable mode-locked pulse was obtained. The mode-locked pulses had a pulse repetition rate of 17.83 MHz and pulse duration of ∼4 ns throughout the mode-locked operation range of 200-600 mW. The recorded maximum average output power was ∼4.88 mW. The signal to noise ratio (SNR) was obtained to be 64.9 dB, which indicates the favorable stability of the mode-locked pulse. These results demonstrate the Co2+:ZnSe thin film grown on a fiber taper has high optical quality and implementation of stable pulse operation on passively mode-locked Er-doped fiber lasers.
Influence of diluted acid mixtures on selective etching of MHz- and kHz-fs-laser inscribed structures in YAG
Authors: Hasse Kore , Kip Detlef , Kränkel Christian
Published: April 2021

We show that the inscription velocity of fs-laser written structures in YAG crystals can be significantly improved by the use of MHz repetition rates for the writing process. Using a 10 MHz inscription laser, record high writing velocities up to 100 mm/s are achieved. Also, the selective etching process is accelerated using a diluted mixture of 22% H3PO4 and 24% H2SO4. The diluted mixture enables selective etching of up to 9.6 mm long, 1 µm wide and 18 µm high microchannels in 23 days. The etching parameter D of 11.2 µm2/s is a factor of 3 higher than previously reported and the selectivity is even increased by an order of magnitude.
Field testing an “acoustic lighthouse”: Combined acoustic and visual cues provide a multimodal solution that reduces avian collision risk with tall human-made structures
Authors: Boycott Timothy J. , Mullis Sally M. , Jackson Brandon E. , Swaddle John P.
Published: April 2021

Billions of birds fatally collide with human-made structures each year. These mortalities have consequences for population viability and conservation of endangered species. This source of human-wildlife conflict also places constraints on various industries. Furthermore, with continued increases in urbanization, the incidence of collisions continues to increase. Efforts to reduce collisions have largely focused on making structures more visible to birds through visual stimuli but have shown limited success. We investigated the efficacy of a multimodal combination of acoustic signals with visual cues to reduce avian collisions with tall structures in open airspace. Previous work has demonstrated that a combination of acoustic and visual cues can decrease collision risk of birds in captive flight trials. Extending to field tests, we predicted that novel acoustic signals would combine with the visual cues of tall communication towers to reduce collision risk for birds. We broadcast two audible frequency ranges (4 to 6 and 6 to 8 kHz) in front of tall communication towers at locations in the Atlantic migratory flyway of Virginia during annual migration and observed birds’ flight trajectories around the towers. We recorded an overall 12–16% lower rate of general bird activity surrounding towers during sound treatment conditions, compared with control (no broadcast sound) conditions. Furthermore, in 145 tracked “at-risk” flights, birds reduced flight velocity and deflected flight trajectories to a greater extent when exposed to the acoustic stimuli near the towers. In particular, the 4 to 6 kHz stimulus produced the greater effect sizes, with birds altering flight direction earlier in their trajectories and at larger distances from the towers, perhaps indicating that frequency range is more clearly audible to flying birds. This “acoustic lighthouse” concept reduces the risk of collision for birds in the field and could be applied to reduce collision risk associated with many human-made structures, such as wind turbines and tall buildings.
Case-control study of patient characteristics, knowledge of the COVID-19 disease, risk behaviour and mental state in patients visiting an emergency room with COVID-19 symptoms in the Netherlands
Authors: van der Valk J. P. M. , Heijboer F. W. J. , van Middendorp H. , Evers A. W. M. , in ‘t Veen J. C. C. M.
Published: April 2021

Background

Coronavirus disease 2019 is a serious respiratory virus pandemic. Patient characteristics, knowledge of the COVID-19 disease, risk behaviour and mental state will differ between individuals. The primary aim of this study was to investigate these variables in patients visiting an emergency department in the Netherlands during the COVID-19 pandemic and to compare the “COVID-19 suspected” (positive and negative tested group) with the “COVID-19 not suspected” (control group) and to compare in the “COVID-19 suspected” group, the positive and negative tested patients.

Methods

Consecutive adult patients, visiting the emergency room at the Franciscus Gasthuis & Vlietland, Rotterdam, the Netherlands, were asked to fill out questionnaires on the abovementioned items on an iPad. The patients were either “COVID-19 suspected” (positive and negative tested group) or “COVID-19 not suspected” (control group).

Results

This study included a total of 159 patients, 33 (21%) tested positive, 85 (53%) negative and 41 (26%) were COVID-19 not suspected (control group). All patients in this study were generally aware of transmission risks and virulence and adhered to the non-pharmaceutical interventions. Working as a health care professional was correlated to a higher risk of SARS-Cov-2 infection (p- value 0.04). COVID-19 suspected patients had a significantly higher level of anxiety compared to COVID-19 not suspected patients (p-value < 0.001). The higher the anxiety, the more seriously hygiene measures were followed. The anxiety scores of the patients with (pulmonary) comorbidities were significantly higher than without comorbidities.

Conclusion

This is one of the first (large) study that investigates and compares patient characteristics, knowledge, behaviour, illness perception, and mental state with respect to COVID-19 of patients visiting the emergency room, subdivided as being suspected of having COVID-19 (positive or negative tested) and a control group not suspected of having COVID-19. All patients in this study were generally aware of transmission risks and virulence and adhered to the non-pharmaceutical interventions. COVID-19 suspected patients and patients with (pulmonary) comorbidities were significantly more anxious. However, there is no mass hysteria regarding COVID-19. The higher the degree of fear, the more carefully hygiene measures were observed. Knowledge about the coping of the population during the COVID-19 pandemic is very important, certainly also in the perspective of a possible second outbreak of COVID-19.
The Werther effect of celebrity suicides: Evidence from South Korea
Authors: Ha Jeongmin , Yang Hee-Seung
Published: April 2021

Since 2003 Korea has experienced the highest suicide rate among OECD countries. One of the societal risk factors that triggers suicide is the contagious nature of suicide. This paper empirically examines the effect of celebrity suicide reports on subsequent copycat suicides, using daily suicide data and information of highly publicized suicide stories in Korea from 2005 to 2018. The findings from the Poisson regression model suggest that the number of public suicides soars after media reports on celebrity suicides. On average, the number of suicides in the population increased by 16.4% within just one day after the reports. Further analysis reveals that female and younger subgroups are more likely to be affected by celebrity suicides. Moreover, the public reacts more strongly to suicide incidents of celebrities of the same gender and even imitates the methods of suicide used by celebrities. This paper highlights the significance of careful and responsible media coverage of suicide stories to prevent copycat suicide. For policymakers, it is crucial to implement regulations not only for traditional media but also for new media where younger people can freely access unfiltered information.
Parameters of biliary hydrodynamic injection during endoscopic retrograde cholangio-pancreatography in pigs for applications in gene delivery
Authors: Huang Yuting , Kruse Robert L. , Ding Hui , Itani Mohamad I. , Morrison Jonathan , Wang Zack Z. , Selaru Florin M. , Kumbhari Vivek
Published: April 2021

The biliary system is routinely accessed for clinical purposes via endoscopic retrograde cholangiopancreatography (ERCP). We previously pioneered ERCP-mediated hydrodynamic injection in large animal models as an innovative gene delivery approach for monogenic liver diseases. However, the procedure poses potential safety concerns related mainly to liver or biliary tree injury. Here, we sought to further define biliary hydrodynamic injection parameters that are well-tolerated in a human-sized animal model. ERCP was performed in pigs, and hydrodynamic injection carried out using a novel protocol to reduce duct wall stress. Each pig was subjected to multiple repeated injections to expedite testing and judge tolerability. Different injection parameters (volume, flow rate) and injection port diameters were tested. Vital signs were monitored throughout the procedure, and liver enzyme panels were collected pre- and post-procedure. Pigs tolerated repeated biliary hydrodynamic injections with only occasional, mild, isolated elevation in aspartate aminotransferase (AST), which returned to normal levels within one day post-injection. All other liver tests remained unchanged. No upper limit of volume tolerance was reached, which suggests the biliary tree can readily transmit fluid into the vascular space. Flow rates up to 10 mL/sec were also tolerated with minimal disturbance to vital signs and no anatomic rupture of bile ducts. Measured intrabiliary pressure was up to 150 mmHg, and fluid-filled vesicles were induced in liver histology at high flow rates, mimicking the changes in histology observed in mouse liver after hydrodynamic tail vein injection. Overall, our investigations in a human-sized pig liver using standard clinical equipment suggest that ERCP-guided hydrodynamic injection will be safely tolerated in patients. Future investigations will interrogate if higher flow rates and pressure mediate higher DNA delivery efficiencies.
Evolution of diversity and dominance of companies in online activity
Authors: McCarthy Paul X. , Gong Xian , Eghbal Sina , Falster Daniel S. , Rizoiu Marian-Andrei
Published: April 2021

Ever since the web began, the number of websites has been growing exponentially. These websites cover an ever-increasing range of online services that fill a variety of social and economic functions across a growing range of industries. Yet the networked nature of the web, combined with the economics of preferential attachment, increasing returns and global trade, suggest that over the long run a small number of competitive giants are likely to dominate each functional market segment, such as search, retail and social media. Here we perform a large scale longitudinal study to quantify the distribution of attention given in the online environment to competing organisations. In two large online social media datasets, containing more than 10 billion posts and spanning more than a decade, we tally the volume of external links posted towards the organisations’ main domain name as a proxy for the online attention they receive. We also use the Common Crawl dataset—which contains the linkage patterns between more than a billion different websites—to study the patterns of link concentration over the past three years across the entire web. Lastly, we showcase the linking between economic, financial and market data by exploring the relationships between online attention on social media and the growth in enterprise value in the electric carmaker Tesla. Our analysis shows that despite the fact that we observe consistent growth in all the macro indicators—the total amount of online attention, in the number of organisations with an online presence, and in the functions they perform—we also observe that a smaller number of organisations account for an ever-increasing proportion of total user attention, usually with one large player dominating each function. These results highlight how evolution of the online economy involves innovation, diversity, and then competitive dominance.
How the persistence of patriarchy undermines the financial empowerment of women microfinance borrowers? Evidence from a southern sub-district of Bangladesh
Authors: Shohel Tunvir Ahamed , Niner Sara , Gunawardana Samanthi
Published: April 2021

A significant body of multi-disciplinary research supports the proposition that women may experience empowerment from microfinance programs. This is based on the assumption that an increase in women’s financial contribution to the household helps to transform gender norms and relations which increases their decision-making power. However, the relationship between the strength and persistence of patriarchal gender norms within the household and women’s financial empowerment needs further exploration. This paper presents the findings of a mixed-method study comprising 331 surveys and 33 in-depth interviews with women receiving microfinance and their husbands in a southern sub-district of Bangladesh; it draws upon gender socialisation and gender performance theory to understand how patriarchal gender norms influence women’s financial empowerment in households receiving microfinance. Findings demonstrate that participation in microfinance programs has not shifted gender norms, nor financially empowered women. Women’s loans were largely controlled by men as prescribed by underlying, unchanged patriarchal gender norms. The inter-generational reproduction of patriarchal gender relations continued to reproduce a strict gendered division of labour that reinforced restrictions on women’s behaviour, mobility, and decision-making domains, and men’s dominance in household and economic decision-making.
Social inclusion of students with special educational needs assessed by the Inclusion of Other in the Self scale
Authors: Vyrastekova Jana
Published: April 2021

How does the participation of students with special educational needs (SEN) in mainstream education affect their social inclusion? We introduce a single-item pictorial measure, the Inclusion of Other in the Self (IOS), to compare the social inclusion of SEN students attending mainstream regular schools to social inclusion of SEN students attending special schools. We collected responses from 138 parents of SEN students aged 4–20, to obtain data on the loneliness, friendships and social inclusion of SEN students. The parents of SEN students attending regular schools did not perceive their children to be less included than parents of SEN students attending special schools. School context decreased SEN students’ perceived loneliness independent of the school type. And while most SEN students’ friendships were formed at school, SEN students attending regular schools had more friends, and these were more likely to live in the same neighborhood. Overall, the social inclusion of SEN students across school types was not affected by the school type, only by the school’s inclusive characteristics.
Gastric polyp detection in gastroscopic images using deep neural network
Authors: Cao Chanting , Wang Ruilin , Yu Yao , zhang Hui , Yu Ying , Sun Changyin
Published: April 2021

This paper presents the research results of detecting gastric polyps with deep learning object detection method in gastroscopic images. Gastric polyps have various sizes. The difficulty of polyp detection is that small polyps are difficult to detect from the background. We propose a feature extraction and fusion module and combine it with the YOLOv3 network to form our network. This method performs better than other methods in the detection of small polyps because it can fuse the semantic information of high-level feature maps with low-level feature maps to help small polyps detection. In this work, we use a dataset of gastric polyps created by ourselves, containing 1433 training images and 508 validation images. We train and validate our network on our dataset. In comparison with other methods of polyps detection, our method has a significant improvement in precision, recall rate, F1, and F2 score. The precision, recall rate, F1 score, and F2 score of our method can achieve 91.6%, 86.2%, 88.8%, and 87.2%.