bluuebunny/crossref_metadata_2025 huggingface dataset:
Gotta Have Money to Make Money? Bargaining Behavior and Financial Need of Microentrepreneurs
Authors: Hardy Morgan , Kagy Gisella , Song Lena
Published: February 2022

Bargaining over real prices with microenterprise owners in Ghana, we show that sellers with less per capita household liquidity agree to lower sale prices. This relationship is robust across firms and within firms over time, even after controlling for a plethora of time-varying observables. A computerized bargaining experiment, with randomized initial payout sizes, corroborates the real-bargaining findings. This pattern can be explained by an application of classical bargaining theory that includes endowments and utility functions with decreasing absolute risk aversion. The potential poverty-multiplying implications of pricing behavior is a key frontier in understanding barriers to the profitability of microenterprises. (JEL D22, G51, L25, L26, O12, O14)
Forward Guidance and Durable Goods Demand
Authors: McKay Alisdair , Wieland Johannes F.
Published: February 2022

We study the monetary transmission mechanism in a quantitative fixed-cost model of durable goods demand. We show that aggregate demand is substantially more sensitive to contemporaneous interest rates than to forward guidance about future interest rates. Reducing the real interest rate one year from now increases output by only 41  percent as much as reducing the real interest rate today. The power of forward guidance declines further at longer horizons. We show analytically and quantitatively that this result is driven by the sensitivity of the extensive margin of durable adjustment to the contemporaneous user cost. (JEL D52, E21, E43, E52)
Investigating the Colour Difference of Old and New Blue Japanese Glass Pigments for Artistic Use
Authors: Chua Lynn , Quan Seah Zi , Yan Gao , Yoo Woo Sik
Published: February 2022

Colour consistency is an important consideration when selecting pigments used on works of art. In this study, we analyse the colour difference between two sets of synthetic blue glass pigments acquired at least 8 years apart from the same manufacturer in Japan. The old pigment set (unused, dry powder with four different grain sizes) appears faded compared to the new set. These pigments are made available for artistic use, commonly in Nihonga or Japanese paintings. Raman spectroscopy and SEM-EDS results characterize these pigments as cobalt aluminate spinels dissolved in leaded glaze, a special class of complex coloured inorganic pigments that is not well-understood in the field of conservation. Colour difference between the old and new pigments with four different grain sizes were quantified by analysing photomicrographs with image analysis software. Blue pigments with coarse and extremely fine grains showed significant colour change compared to pigments with medium and fine grain sizes. The high occurrence of crystallites in the finer grains give a final colour that is bluer and lighter. Possible causes for the colour difference including manufacturing methods and storage environment are discussed.
Investigating the Iron-Making Process through the Scientific Analysis of By-products Obtained during Iron-Making from Songdu-ri Site in Jincheon, Korea
Authors: Jung Da Yeon , Cho Nam Chul
Published: February 2022

The study, iron-making process was examined through the scientific analysis of six by-products that were obtained during iron making at the Songdu-ri site in Jincheon. The total Fe content of the slags excavated from the Songdu-ri site was 36.29–54.61 wt%, whereas the deoxidation agent was 26.48–49.08 wt%. The compound analysis result indicated that fayalite and wüstite are the main compounds in slag. Furthermore, the microstructure analysis result confirmed the presence of fayalite and wüstite in the slag. It can be inferred from the flat shape in a bright matrix structure of the hammer scales that forging was performed in the latter stage. The Raman micro-spectroscopy results confirmed that the surface was hematite (Fe2O4), middle layer was magnetite (Fe3O4), and inner layer was wüstite (FeO). The presence of smelting and smithing slags, spheroid hammer scales, and flake hammer scales suggests that at the Songdu-ri site, iron-making process is carried out by division of labor into producing iron bloom through direct smelting, refining and forge welding, and ingot production.
Fungal Distribution of the Janggyeong Panjeon, the Depositories for the Tripitaka Koreana Woodblocks in the Haeinsa Temple
Authors: Hong Jin Young , Kim Young Hee , Lee Jeong Min , Kim Soo Ji , Park Ji Hee
Published: February 2022

Many investigations have been conducted on the biological damage and environmental conditions necessary to preserve the Janggyeong Panjeon and Daejanggyeongpan (woodblocks). We performed a survey on the concentration and diversity of airborne fungi in the Janggyeong Panjeon and compared them with the results of a survey from 2012. The temperature of the Beopbojeon building was slightly lower, while the relative humidity was higher than those found at the Sudarajang building. The concentration of airborne fungi in the Beopbojeon was 1.44-fold that of the Sudarajang. It was confirmed that the concentration and diversity of airborne fungi in the Janggyeong Panjeon differed depending on the sampling site. In total, 23 fungal genera were identified from the air samples, and 11 fungal and 1 bacterial genera were identified from the surface of the woodblocks. Among these, only five types of fungi were commonly distributed in the indoor air and surface of the Daejanggyeongpan; however, 58.3% of the fungi identified on the surface of the woodblocks were not observed in the in the air samples. The surface-dwelling fungi may accumulate dust to form microbial communities over time.
Etude de la dynamique spatio-temporelle de la forêt des Ait Daoud ou Ali (Haut Atlas central, Maroc) en utilisant les techniques géospatiales.
Authors: Hili Aïman , Bissour Rachid , Jaa Farid , Reddad Hanane , El Jouhary Yassine
Published: February 2022

Depuis longtemps l’Homme cherche l’exploitation des ressources naturelles à des fines quotidiennes. Ainsi, le développement scientifique et technologique actuel lui a facilité et lui a donné des vraies opportunités pour la surexploitation de ces ressources en général et du couvert végétal en particulier. Afin de montre cette exploitation nous voulons, dans le présent article, étudier l’évolution du couvert végétal de la forêt des Ait Daoud ou Ali, située dans le Haut Atlas central sur une superficie de 30 860 ha, entre 1972, 1999 et 2020, en se basant sur la télédétection et l’outil SIG. Pour ce qui concerne la méthodologie de travail, l’étude multi-chronique de la dynamique du couvert végétal de la zone d’étude, repose sur l’analyse spatio-temporelle et le traitement des images satellitaires par la télédétection spatiale. En effet, dans le présent papier nous avons opté cette démarche qui s’appuie sur l’utilisation des données des images du satellite de LandSat de trois types; il s’agit des images de type MSS, ETM et Oli, pour trois dates 1972, 1999 et 2020 (période de 48 ans) pour identifier les différences spatiales du couvert végétal entre les trois dates choisies. En effet, l’étude de la dynamique du couvert végétal de la forêt des Ait Daoud ou Ali entre 1972, 1999 et 2020, a montré une variation spatio-temporelle très importante, liée essentiellement à plusieurs facteurs (naturels et humaines). La comparaison des résultats de la classification des images Landsat, a montré un recul et une dégradation importante du couvert végétal entre 1972 et 1999 de 12% de la surface totale de la zone d’étude. Cette dégradation est justifiée par l’intervention de plusieurs facteurs, notamment les conditions climatiques et les périodes sèches qu’a connu le Maroc à cette période. Pour la deuxième période (1999-2020), le traitement a montré une progression du couvert végétal de l’ordre de 10%. Dans cette étude, nous avons mis en évidence l’impact des facteurs naturels et notamment les actions anthropiques sur la dynamique de la forêt des Ait Daoud ou Ali située dans Haut Atlas Central, en se basant sur l’utilisation des techniques géospatiales qui nous ont permis d’avoir des informations très précises relatives à la dynamique spatio-temporelle du couvert végétal.
The Market for Fake Reviews
Authors: He Sherry , Hollenbeck Brett , Proserpio Davide
Published: February 2022

This paper studies the market for fake product reviews on Amazon.com.
Frontiers: Supporting Content Marketing with Natural Language Generation
Authors: Reisenbichler Martin , Reutterer Thomas , Schweidel David A. , Dan Daniel
Published: February 2022

Supporting Content Marketing with Natural Language Generation
Clinical and epidemiological profile of elderly patients seen in a hypertensive emergency at a public hospital in the state of Rio de Janeiro – Hypertensive emergency in the elderly
Authors: De Senne Júlia A. , De Oliveira Igor Fernando S. , Oliveira Karolina De S. , Rangel Maria Eduarda A. , Raimundo Raphael F. de O. , Oliveira Rodrigo W. de , Tenorio Vitor
Published: February 2022

Introduction: Hypertensive emergencies (HE) are clinicalentities characterized by an acute and significant increasein blood pressure (BP) associated with severe symptoms thatevidence target organ damage. Objective: To analyze the clinicaland epidemiological profile of elderly patients treated ina hypertensive emergency at a public hospital in the state ofRio de Janeiro. Method: This study is prospective and descriptive.Information was collected from August to October, 2020using medical records and processed using the Statistic Statsoftprogram. Pearson’s test was performed for univariate analysis.Results: The sample consisted of 109 patients. The averageage found was 73 years old, with a predominance of males(69.72%) and brown skin (36.69%). Approximately 72.48% ofthe patients had a history of Systemic Arterial Hypertension(SAH), however, (50.46%) reported that they did not regularlyuse antihypertensive medication. Target organ injuries wereischemic stroke (58.71%), followed by acute coronary syndrome(24.77%), hemorrhagic stroke (9.17%) and edema acutelung disease (7.33%). Regarding the BP values found at admission,the mean systolic pressure was 205.0 mmHg, while themean diastolic pressure was 127.0 mmHg. Conclusion: Ischemicstroke was the most frequent HE in the sample. It is necessaryto put in place measures to prevent risk factors associated withSAH, as well as to control blood pressure levels to reduce thenumber of consultations due to hypertensive emergencies andother complications of cardiovascular diseases.Keywords: Emergency; Hypertension; Prevalence.
Effect of Whole Body Vibration on Flexibility in Stroke Patients: A Pilot Study
Authors: Dincher Andrea , Wydra Georg
Published: February 2022

Background: The motor consequences of a stroke are mainlytreated with physiotherapy and blood thinning drugs. Inexercise therapy with whole body vibration, studies withother patient groups show positive effects already after asingle application. In stroke patients, the effectiveness ofwhole body vibration is still quite inconsistent. Therefore, thepresent study aims to investigate the effectiveness of wholebody vibration on flexibility in stroke patients. Hypothesis:Whole body vibration has a positive effect on flexibility instroke patients. Methods: 13 stroke patients (age 68.23 ± 8.93years, mean time past since stroke 10.82 ± 8.83 months) wererandomized in two groups subjected to whole body vibrationat 6 and 12 Hz, respectively. Before and after the treatment of 5x 60 seconds with a break of 60 seconds between each set, theSit and Reach test was performed (3 runs each, the respectivemean value was evaluated). Results: Both groups improvedtheir performance highly significantly from pre- to posttest(F(1,11) = 9.05; p = 0.01). There is no difference between groupsand no interaction effect for factor time*group. Conclusions:Even lower application frequencies (6 and 12 Hz) can have apositive effect on the flexibility of stroke patients. Nevertheless,further studies must try to develop an optimal trainingprotocol for this patient group.
Synchrotron Radiation Study on Ancient Burnt Rice Found at Archaeological Sites in Thailand
Authors:   Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai, 50200 Thailand, Boonruang Chatdanai ,   Center of Excellence in Materials Science and Technology, Chiang Mai University, Chiang Mai 50200, Thailand, Won-in Krit ,   Department of Earth Sciences, Faculty of Science, Kasetsart University, Bangkok 10900 Thailand, Tancharakorn Somchai ,   Synchrotron Light Research Institute, Nakhon Ratchasima 30000 Thailand, Pakawanit Phakkananan ,   Synchrotron Light Research Institute, Nakhon Ratchasima 30000 Thailand, Thumanu Kanjana ,   Synchrotron Light Research Institute, Nakhon Ratchasima 30000 Thailand, Dararutana Pisutti ,   Retired Army Officer at the Royal Thai Army, Lopburi 15000 Thailand
Published: February 2022

Rice is the food staple for most of the world’s population especially Asians. It is also the essence of life of people in Thailand. Archaeological evidence based on the paddy rice reveals the rice planting in northeastern Thailand over 5,000 years ago. The burnt rice grains have been found in many archaeological sites in Thailand, which are involved with the religious ceremony and home prosperity. In this work, the synchrotron radiation has been applied to investigate the elemental distribution, chemical composition and bio-molecular structure, and three-dimensional segmentation of the ancient burnt rice samples from Nakorn Nayok (Ban Dong Lakon), Suphan Buri (U-Thong), and Prachin Buri (Sri Mahosot) using micro-beam XRF (SR μ-XRF), Infrared spectroscopy (SR IR), and X-ray tomographic microscopy based on synchrotron radiation (SR XTM), respectively. Field emission scanning electron microscope (FE SEM) incorporated with energy dispersive spectrometer (EDS) have been carried out in order to characterize the structure and composition of samples. It has been found that the grains are oblong in shape with a rough surface. Major elements in the grains are C, Si, Ca, and Al. Other trace elements such as Ti, Cr, Mn, Fe, Ni, Cu, and Zn are also detected. The IR spectra provide some information about molecular bonds. The tomographic investigations reveal the internal structure of ancient burnt rice.
Shear-Flexure-Interaction Frame Element Inclusion of Bond-Slip Effect for Seismic Analysis of Non-Ductile RC Columns
Authors:   Civil Engineering Program, School of Engineering, University of Phayao, Phayao 56000, Thailand, Sae-Long Worathep , Limkatanyu Suchart ,   Department of Civil Engineering, Faculty of Engineering, Prince of Songkla University, Songkhla 90112, Thailand, Damrongwiriyanupap Nattapong ,   Civil Engineering Program, School of Engineering, University of Phayao, Phayao 56000, Thailand
Published: February 2022

T his paper demonstrates the effect of bond-interfaces slip on the shear responses within the non-ductile reinforced concrete (RC) columns. Those columns were conducted as the flexure-shear critical members, which were commonly found in the existing RC frame structures constructed before the regulation of recent seismic codes. To represent the behaviors of those columns, the proposed model is developed within the framework of the forced-based formulation under the Timoshenko beam kinematic assumption. The axial-flexure interaction of the RC frame element is considered through the fiber-section model while the shear action couples to the flexural action through the UCSD shear-strength model within the shear constitutive model. Finally, one simulation is employed to verify the model performance to predict complex behaviors of the non-ductile RC columns for seismic analysis and to discuss the effect of bond-interfaces slip on those responses. From the results, it confirms that the proposed model is simple but accurate. Furthermore, the model can well represent several salient features of the non-ductile RC columns such as the shear-flexure interaction effect, the strength degradation in shear due to the increasing curvature ductility demand, the gradual spread inelasticity, and the weakened shear responses due to the bond-slip effect. The predicted maximum shear force is well corresponding to the value obtained from the experiment with an error of about 0.83% while the error obtained from the frame model without the bond-slip effect is about 2.58%.
SIGNIFICAÇÃO E MUNDO EM SER E TEMPO
Authors: Dos Anjos Santos Maiara
Published: February 2022

Esse trabalho tem como proposta compreender e apresentar, criticamente, a concepção de significação (Sinn; Bedeutung) e mundo na obra Ser e Tempo de Martin Heidegger (1889-1976), bem como, a contribuição destes conceitos para uma discussão sobre a essência da linguagem.
Promoting Self-Determination in Community Contexts: Experiences With Implementing the Self-Determined Learning Model of Instruction
Authors: Dean Evan E. , Hagiwara Mayumi , Jones Jennifer , Gallus Kami , Shogren Karrie A.
Published: February 2022

This article describes a pilot project focused on creating opportunities for self-determination to enhance the community participation outcomes of adults with intellectual and developmental disabilities using the Self-Determined Learning Model of Instruction (SDLMI). The pilot project grew out of a partnership between researchers at a university and the state's developmental disabilities services system in their state and emerged from collaborative discussions of needs in the community. The purpose of the project was to (a) investigate effective ways to deliver the SDLMI in a community context and (b) identify the systemic changes needed to enable scaling-up of supports for self-determination. This article introduces a framework for implementing the SDLMI in the community and highlight lessons learned through community-based implementation.
Twisted elliptical multi-Gaussian Schell-model beams and their propagation properties: reply
Authors: Wang Haiyun , Peng Xiaofeng , Liu Lin , Wang Fei , Cai Yangjian
Published: February 2022

The correction pointed out by Nemes [J. Opt. Soc. Am. A
39, 667 (2022)JOAOD60740-323210.1364/JOSAA.435756] to
our paper [J. Opt.
Soc. Am. A 37, 89
(2020)JOAOD60740-323210.1364/JOSAA.37.000089] is welcome. The
author claims that the beam propagation factors

M
x
2

,

M
y
2

are inadequate to characterize
twisted elliptical multi-Gaussian Schell-model (TEMGSM) beams, which
are introduced in our paper. Further, the author points out that there
are two pairs of independent, normalized invariants to classify the
TEMGSM beams. In this reply, we present the numerical example of the
normalized intrinsic propagation invariants of the TEMGSM beams.
Ultrafast metamaterial all-optical switching based on coherent modulation
Authors: Wang Tianrang , Tang Jian , Chen Ming , Xiong Jianfeng , Wang Hexuan , Xu Jie , Qu Shiliang , Cheng Yu , Yuan Libo
Published: February 2022

We report a demonstration of an ultrafast all-optical switching with unique light control effects. The all-optical switching consists of a gold film with asymmetric split rings and a silica substrate. The device effectively controls the transmission and absorption of continuous pulses in the communication band (1200-1800 nm) and short pulses with a pulse duration of 80 fs by using the interaction of two coherent beams on nano-metamaterials with a thickness of only 50 nm. The metamaterial can achieve more than 90 % output control under continuous light irradiation. When the pulse duration is 80 fs, the switching contrast ratio is greater than 3 : 1 and the modulation bandwidth is greater than 12.5 THz. Switching time can be on the order of femtosecond. This paper provides a new structure for ultra-high speed optical data processing components in coherent networks.
Enhancement of the light extraction characteristics and wide-angle emissive behavior of deep-ultraviolet flip-chip light-emitting diodes by using optimized optical films
Authors: Ye Zhi-Ting , Wei Lai , Tien Ching-Ho , Pan Shyi-Ming
Published: February 2022

We propose the use of optical films to enhance the light extraction efficiency (LEE) and wide-angle emission of traditional packaged deep-ultraviolet light-emitting diodes (DUV-LEDs). Total internal reflection occurs easily in DUV-LEDs because they contain sapphire, which has a high refractive index. DUV-LEDs also contain an aluminum nitride (AlN) ceramic substrate, which has high light absorption in the ultraviolet band. Photons are absorbed by the sapphire and AlN ceramic substrate, which reduces the LEE of DUV-LEDs. By adding a brightness enhancement film (BEF) on the sapphire surface and a high-reflection film (HRF) on the surface of the AlN ceramic substrate, the LEE of DUV-LEDs can be increased. Moreover, we designed a single-layer metal reflective film (SMRF) on the upper surface of the quartz glass in order to achieve wide-angle emission. Experimental results indicated that compared with traditional packaged DUV-LEDs, the light output power and external quantum efficiency of DUV-LEDs with a plated BEF, HRF, and SMRF increased by 18.3% and 18.2%, respectively. Moreover, an emission angle of 160° was achieved. In a reliability test, DUV-LEDs maintained more than 95% of the initial forward voltage and light output power after 1000 h of operation at 25°C, which indicated that the addition of an optical film can improve the light efficiency and long-term reliability of DUV-LEDs.
Reduction of speckle noise in digital holography using a neighborhood filter based on multiple sub-reconstructed images
Authors: Chen Kai , Chen Li , Xiao JiaQi , Li JinYang , Hu YiHua , Wen KunHua
Published: February 2022

The application of digital holography in several fields is limited since speckle destroys the original information of the reconstructed image. This paper proposes a neighborhood filter based on multiple sub-reconstructed images according to the random distribution of speckle noise. In this method, the denoised value is equal to the weighted sum of neighboring pixel values, and the weight is calculated by the degree of correlation between different positions of multiple sub-holograms. The experimental results show that the method can greatly reduce the speckle noise, and its noise reduction performance is superior to traditional digital image processing algorithms.
Self-healing of the bored helico-conical beam
Authors: Zeng Jinfu , Cheng Shubo , Liu Shuo , Zhang Geng , Tao Shaohua , Yang Wenxing
Published: February 2022

We investigate the dynamic evolution and self-healing properties of the bored helico-conical beams with different filter parameter S in this paper. The relative error coefficient, D, is utilized to judge the self-healing effect of the bored helico-conical beam. The result demonstrates that the self-healing effect of the bored beams will be perfect when D approaches to 0. We also discuss the influence of the filter parameter S on the effective self-healing distance theoretically and experimentally. The result demonstrates that the effective self-healing distance decreases exponentially with the increasing filter parameter S. Moreover, the corresponding transverse energy flows of the bored beams are analyzed. The experimental results of the dynamic evolution for the bored helico-conical beams agree with the simulation ones well.
Quantitative detection of defect size based on infrared thermography: temperature integral method
Authors: Zhu Pengfei , Wu Dan , Yin Lingxiao , Han Wei
Published: February 2022

Quantitative detection of the defect size by infrared thermography is difficult. In this paper, a novel temperature integral method (TIM) is introduced for the quantitative detection of the defect size. The TIM integrates the temperature values of each pixel across the defect area to obtain the defect sizes quantitatively and conveniently. The performance of the TIM on the defect size detection is evaluated thoroughly with both experiments and simulations. Furthermore, the TIM method was compared with existing methods for quantitative detection of defect size. The results indicate robustness and accuracy of TIM.
Erbium chloride silicate-based vertical cavity surface-emitting laser at the near-infrared communication band
Authors: Zhao Hepeng , Zhao Xinchao , Zhang Xuehong , Cui Zhuangzhuang , Ou-Yang Yu , Xie Maobin , Zheng Min , Guan Xueyu , Wu Lijun , Zhou Xinglei , Li Lihui , Zhang Yushuang , Li Yang , Jiang Ying , Lu Wei , Zhu Xiaoli , Peng Chao , Wang Xiao , Wang Shaowei , Zhuang Xiujuan
Published: February 2022

Silicon-based integrated optoelectronics has become a hotspot in the field of computers and information processing systems. An integrated coherent light source on-chip with a small footprint and high efficiency is one of the most important unresolved devices. Here, we realize a silicon-based vertical cavity surface-emitting laser in the near-infrared communication band by making efforts in both controlled preparation of high-gain erbium silicate materials and novel design of high optical feedback microcavity. Single-crystal erbium/ytterbium silicate microplates with erbium concentration as high as 5 × 1021 cm−3 are controlled prepared by a chemical vapor deposition method. They can produce strong luminescence with quite a long lifetime (2.3 ms) at the wavelength of 1.5 μm. By embedding the erbium silicate microplates between two dielectric Bragg reflectors, we construct a vertical cavity surface-emitting laser at 1.5 μm, with a lasing threshold as low as 20 μJ/cm2 and Q factor of nearly 2000. Our study provides a new pathway to achieve a sub-micrometer coherent light source for optical communication.
Refraction of space–time wave packets in a dispersive medium
Authors: Yessenov Murat , Faryadras Sanaz , Benis Sepehr , Hagan David J. , Van Stryland Eric W. , Abouraddy Ayman F.
Published: February 2022

Space–time (ST) wave packets are a class of pulsed optical beams whose spatiotemporal spectral structure results in propagation invariance, tunable group velocity, and anomalous refractive phenomena. Here, we investigate the refraction of ST wave packets normally incident onto a planar interface between two dispersive, homogeneous, isotropic media. We formulate a new, to the best of our knowledge, refractive invariant for ST wave packets in this configuration, from which we obtain a law of refraction that determines the change in their group velocity across the interface. We verify this new refraction law in ZnSe and CdSe, both of which manifest large chromatic dispersion at near-infrared frequencies in the vicinity of their band edges. ST wave packets can thus be utilized in nonlinear optics for bridging large group-velocity mismatches in highly dispersive scenarios.
High-efficiency grating coupler based on fast directional optimization and robust layout strategy in 130 nm CMOS process
Authors: Luo Xiangyu , Mi Guangcan , Li Yanbo , Chu Tao
Published: February 2022

We experimentally demonstrated a high-efficiency grating coupler by combining an interleaved etch and apodized structure for fiber-to-chip coupling. The grating coupler was optimized using the fast directional optimization method to achieve apodization. The grating coupler utilized a layout strategy involving an extended mask to avoid alignment errors for a multi-etch structure. The coupling efficiency was measured to be −2.2 dB at a wavelength of 1549 nm with a 3 dB bandwidth of 47 nm. The grating coupler, having no gold reflector, subwavelength index matching structure, or additional material layers, was fabricated using a commercial silicon photonics process with a minimum feature size of 140 nm. This grating coupler design provides a robust and effective coupling scheme and the proposed method can be employed to adopt the design in accordance with standard foundry design rules.
The role of childrens’ vaccination for COVID-19—Pareto-optimal allocations of vaccines
Authors: Gavish Nir , Katriel Guy
Published: February 2022

COVID-19 vaccines have been approved for children of age five and older in many countries. However, there is an ongoing debate as to whether children should be vaccinated and at what priority. In this work, we use mathematical modeling and optimization to study how vaccine allocations to different age groups effect epidemic outcomes. In particular, we consider the effect of extending vaccination campaigns to include the vaccination of children. When vaccine availability is limited, we consider Pareto-optimal allocations with respect to competing measures of the number of infections and mortality and systematically study the trade-offs among them. In the scenarios considered, when some weight is given to the number of infections, we find that it is optimal to allocate vaccines to adolescents in the age group 10-19, even when they are assumed to be less susceptible than adults. We further find that age group 0-9 is included in the optimal allocation for sufficiently high values of the basic reproduction number.
Plasma generated ozone and reactive oxygen species for point of use PPE decontamination system
Authors: Huang Min , Hasan Md Kamrul , Rathore Kavita , Hil Baky Md Abdullah , Lassalle John , Kraus Jamie , Burnette Matthew , Campbell Christopher , Wang Kunpeng , Jemison Howard , Pillai Suresh , Pharr Matt , Staack David
Published: February 2022

This paper reports a plasma reactive oxygen species (ROS) method for decontamination of PPE (N95 respirators and gowns) using a surface DBD source to meet the increased need of PPE due to the COVID-19 pandemic. A system is presented consisting of a mobile trailer (35 m3) along with several Dielectric barrier discharge sources installed for generating a plasma ROS level to achieve viral decontamination. The plasma ROS treated respirators were evaluated at the CDC NPPTL, and additional PPE specimens and material functionality testing were performed at Texas A&M. The effects of decontamination on the performance of respirators were tested using a modified version of the NIOSH Standard Test Procedure TEB-APR-STP-0059 to determine particulate filtration efficiency. The treated Prestige Ameritech and BYD brand N95 respirators show filtration efficiencies greater than 95% and maintain their integrity. The overall mechanical and functionality tests for plasma ROS treated PPE show no significant variations.
Seed priming improved salt-stressed sorghum growth by enhancing antioxidative defense
Authors: Guo Xiaoqian , Zhi Wenfang , Feng Yuntong , Zhou Guisheng , Zhu Guanglong
Published: February 2022

Seed priming is regarded as a beneficial and effective method enhancing performance of plants grown under stress conditions. This study illustrated the effect of four seed priming agents (2% H2O2, 52 mM NaCl, 50 mM KCl, 250 mM MgSO4) on two sorghum cultivars (Canada sorghum CFSH-30 and sorghum ‘1230’) grown in saline soils. Sorghum growth characteristics and biochemical parameters were investigated. Seed priming treatments alleviated the adverse effects of salt stress by decreasing MDA content and enhancing antioxidant enzymes (CAT, POD and SOD) activities and proline content, and hence increased sorghum fresh and dry weight. In terms of various parameters, sorghum ‘1230’ was more suitable to be grown in saline soil, and 52 mM NaCl and 50 mM KCl were the optimum priming agents to improve the performance of salt-stressed sorghum.
Significance of eggshell morphology as an additional tool to distinguish species of sand flies (Diptera: Psychodidae: Phlebotominae)
Authors: Jariyapan Narissara , Tippawangkosol Pongsri , Sor-Suwan Sriwatapron , Mano Chonlada , Yasanga Thippawan , Somboon Pradya , Depaquit Jérôme , Siriyasatien Padet
Published: February 2022

Morphological characteristics of eggshells are important in sand fly ootaxonomy. In this study, eggshells from Phlebotomus stantoni Newstead, Sergentomyia khawi (Raynal), and Grassomyia indica (Theodor) sand flies collected in Chiang Mai province, Thailand were examined and characterized using light microscopy (LM) and scanning electron microscopy (SEM). Then, eggshell morphology of these three species was described for the first time. Each gravid female was forced to lay eggs by decapitation and the eggs were collected for SEM analysis. Egg laying females were identified by morphological examination and molecular typing using cytochrome b (Cytb) as a molecular marker. The chorionic sculpturing of Ph. stantoni eggs combines two patterns on the same egg: unconnected parallel ridges and reticular patterns. Sergentomyia khawi and Gr. indica have similar chorionic polygonal patterns, but their exochorionic morphology and aeropylar area are different. Results indicate that eggshell morphological characteristics such as chorionic pattern, exochorionic morphology, inter-ridge/boundary area, aeropylar area (including the number of aeropyles) and basal layer, can be useful to develop morphological identification keys of eggs. These can serve as an additional tool to distinguish species of sand flies. In addition, the chorionic sculpturing of the eggs of the three species of sand flies observed by LM is useful for species identification in gravid females with spermathecae obscured by eggs.
Neisseria gonorrhoeae infection in female sex workers in an STI clinic in Nairobi, Kenya
Authors: Abdullahi Amina , Nzou Samson Muuo , Kikuvi Gideon , Mwau Matilu
Published: February 2022

Background

Gonorrhea caused by Neisseria gonorrhoeae is the second most prevalent curable sexually transmitted infection worldwide. Female Sex Workers (FSWs) are at a higher risk of contracting gonorrhea due to their risky sexual behaviors like inconsistent condom use and multiple sexual partners. We determined the prevalence and risk factors associated with gonorrhea and its antimicrobial susceptibility pattern among symptomatic FSWs attending Sexual Workers Outreach Program (SWOP) city clinic in Nairobi, Kenya.

Methods

Using convenience sampling, we recruited 379 female sex workers from SWOP City clinic in Nairobi County. We administered a semi-structured questionnaire to collect data on socio-demographics and behavioral risk factors associated with gonorrhea. We also conducted three focus groups. Two endocervical swabs were collected from each participant by the attending physician for the laboratory identification of Neisseria gonorrhoeae. An antimicrobial susceptibility test was performed using the disc diffusion method.

Results

Twenty-four out of 379 (6.3%) participants tested positive for gonorrhea by PCR. The significant risk factors associated with gonorrhea were having multiple sexual partners in the previous two weeks, primary education, and being in the age group of 38–49 years (p < 0.05).

From the qualitative data, sex work disclosure, and difficulty in engaging protected sex with their partner, and unprotected sex with their clients due to more money from the client, PREP, and alcohol use made the female sex workers vulnerable to gonorrhea exposure and or risky sexual behavior. The culture-positive sample result yielded complete (100%) resistance to all the antimicrobials used.

Conclusion

Neisseria gonorrhoeae infection is prevalent among symptomatic FSWs in Nairobi. Multiple sexual partners, being in age group 38–49 years and having primary education were the factors associated with gonorrhea among the study participants. Based on our identification of a highly resistant isolate, we strongly recommend increasing capacity for culture-based diagnosis and susceptibility testing.
Dynamics of natural product Lupenone as a potential fusion inhibitor against the spike complex of novel Semliki Forest Virus
Authors: Mukerjee Nobendu , Das Anubhab , Maitra Swastika , Ghosh Arabinda , Khan Prattusha , Alexiou Athanasios , Dey Abhijit , Baishya Debabrat , Ahmad Faizan , Sachdeva Punya , Al-Muhanna Muhanna K.
Published: February 2022

The Semliki Forest Virus (SFV) is an RNA virus with a positive-strand that belongs to the Togaviridae family’s Alphavirus genus. An epidemic was observed among French troops stationed in the Central African Republic, most likely caused by the SFV virus. The two transmembrane proteins El and E2 and the peripheral protein E3 make up the viral spike protein. The virus binds to the host cell and is internalized via endocytosis; endosome acidification causes the E1/E2 heterodimer to dissociate and the E1 subunits to trimerize. Lupenone was evaluated against the E1 spike protein of SFV in this study based on state-of-the-art cheminformatics approaches, including molecular docking, molecular dynamics simulation, and binding free energy calculation. The molecular docking study envisaged major interactions of Lupenone with binding cavity residues involved non-bonded van der Waal’s and Pi-alkyl interactions. Molecular dynamic simulation of a time scale 200 ns corroborated interaction pattern with molecular docking studies between Lupenone and E1 spike protein. Nevertheless, Lupenone intearcation with the E1 spike protein conforming into a stable complex substantiated by free energy landscape (FEL), PCA analysis. Free energy decomposition of the binding cavity resdiues of E1 spike protein also ensured the efficient non-bonded van der Waal’s interaction contributing most energy to interact with the Lupenone. Therefore, Lupenone interacted strongly at the active site conforming into higher structural stability throughout the dynamic evolution of the complex. Thus, this study perhaps comprehend the efficiency of Lupenone as lead molecule against SFV E1 spike protein for future therapeutic purpose.
Predictors of dream enactment behavior among medical students: The case of the University of Gondar, Ethiopia
Authors: Dagnew Baye , Diress Mengistie , Getnet Mihret , Seid Mohammed Abdu , Fekadu Sofonias Addis , Gela Yibeltal Yismaw , Yeshaw Yigizie , Belsti Yitayeh , Akalu Yonas
Published: February 2022

Introduction

Dream enactment behavior is one of the features of rapid eye movement sleep behavior disorder. It might be a manifestation of neurodegenerative diseases and can lead to fall associated injuries. There is no evidence of dream enactment behavior and its associated factors in Ethiopia. Hence, this study targeted to pinpoint the predictors of dream enactment behavior among Medical students at the University of Gondar.

Methods

The cross-sectional survey was carried out at the University of Gondar among Medical students selected by simple random sampling technique from Dec 2020 to Feb 2021. We used a structured pretested questionnaire to collect the data and dream enactment behavior was evaluated using rapid eye movement sleep behavior disorder single question. Descriptive statistics were computed, and determinant factors were identified using binary logistic regression model. In the final model, explanatory variables with a p<0.05 were considered as predictors (statistically significant) of the dream enactment behavior. The strength of association was determined using adjusted odds ratio (AOR) with its 95% CI.

Results

Four-hundred and twelve students took part in the study with 97.4% response rate. The mean age of participants was 20.82(±1.88) years and 291(70.63%) were males. The prevalence of dream enactment was 34.47% (95% CI: 30.02–39.20). Daytime sleepiness score (AOR = 1.104; 95% CI: 1.053–1.160), age (AOR = 1.15; 95% CI: 1.019–1.290), monthly pocket money (AOR = 0.9991; 95% CI: 0.9985–0.9997), alcohol drink (AOR = 2.71; 95% CI: 1.076–6.846), and perceived stress (AOR = 3.854; 95% CI: 1.802–8.242) were statistically significant factors of dream enactment behavior.

Conclusions

In this study, the magnitude of dream enactment behavior was high which was significantly associated with daytime sleepiness score, age, monthly pocket money, alcohol drink, and perceived stress all of which are modifiable except age. The University of Gondar has to plan a strategy to avert the condition via the prevention of the determinant factors. Students need to reduce stress and avoid alcohol drink. We strongly urge forthcoming scholars to ascertain association of dream enactment and academic performance of university students.
Nutritional value of black soldier fly (Hermetia illucens) larvae processed by different methods
Authors: Zulkifli Nor Fatin Najihah Mohamad , Seok-Kian Annita Yong , Seng Lim Leong , Mustafa Saleem , Kim Yang-Su , Shapawi Rossita
Published: February 2022

Nutritional value of black soldier fly (Hermetia illucens) larvae (BSFL) processed by three different methods of treatment was compared. The resulting products were the spray-dried BSFL (SPR), oven-dried BSFL 1 (OVN1) and oven-dried BSFL 2 (OVN2). Proximate chemical composition, and profiles of amino acids, fatty acids, minerals, heavy metals, vitamins and nucleotides were analysed and compared. The tested BSFL meals were considered to have a good profile of essential amino acids (EAAs), with leucine, lysine, valine, and histidine being the dominant EAAs. Their content of saturated fatty acids exceeded that of the unsaturated fatty acids. Vitamins B1, B2, and C were also present in the samples. Minerals such as calcium, potassium, phosphorus, sodium, magnesium, zinc, iron, manganese and copper were found to be in adequate amounts in almost all the samples. Heavy metals in the BSFL meals were mostly below 1g kg-1. Nucleotides such as inosine monophosphate and uridine monophosphate occurred in all the BSFL meals. Other nucleotides, including guanosine monophosphate, adenosine monophosphate, xanthosine monophosphate, and cytidine monophosphate were detected in either or both of SPR and OVN2. In general, the nutritional value of the BSFL meals tested in the present study was influenced by the method of processing.
Automated detection scheme for acute myocardial infarction using convolutional neural network and long short-term memory
Authors: Muraki Ryosuke , Teramoto Atsushi , Sugimoto Keiko , Sugimoto Kunihiko , Yamada Akira , Watanabe Eiichi
Published: February 2022

The early detection of acute myocardial infarction, which is caused by lifestyle-related risk factors, is essential because it can lead to chronic heart failure or sudden death. Echocardiography, among the most common methods used to detect acute myocardial infarction, is a noninvasive modality for the early diagnosis and assessment of abnormal wall motion. However, depending on disease range and severity, abnormal wall motion may be difficult to distinguish from normal myocardium. As abnormal wall motion can lead to fatal complications, high accuracy is required in its detection over time on echocardiography. This study aimed to develop an automatic detection method for acute myocardial infarction using convolutional neural networks (CNNs) and long short-term memory (LSTM) in echocardiography. The short-axis view (papillary muscle level) of one cardiac cycle and left ventricular long-axis view were input into VGG16, a CNN model, for feature extraction. Thereafter, LSTM was used to classify the cases as normal myocardium or acute myocardial infarction. The overall classification accuracy reached 85.1% for the left ventricular long-axis view and 83.2% for the short-axis view (papillary muscle level). These results suggest the usefulness of the proposed method for the detection of myocardial infarction using echocardiography.
Analyses of human cancer driver genes uncovers evolutionarily conserved RNA structural elements involved in posttranscriptional control
Authors: Tompkins Van S. , Rouse Warren B. , O’Leary Collin A. , Andrews Ryan J. , Moss Walter N.
Published: February 2022

Experimental breakthroughs have provided unprecedented insights into the genes involved in cancer. The identification of such cancer driver genes is a major step in gaining a fuller understanding of oncogenesis and provides novel lists of potential therapeutic targets. A key area that requires additional study is the posttranscriptional control mechanisms at work in cancer driver genes. This is important not only for basic insights into the biology of cancer, but also to advance new therapeutic modalities that target RNA—an emerging field with great promise toward the treatment of various cancers. In the current study we performed anin silicoanalysis on the transcripts associated with 800 cancer driver genes (10,390 unique transcripts) that identified 179,190 secondary structural motifs with evidence of evolutionarily ordered structures with unusual thermodynamic stability. Narrowing to one transcript per gene, 35,426 predicted structures were subjected to phylogenetic comparisons of sequence and structural conservation. This identified 7,001 RNA secondary structures embedded in transcripts with evidence of covariation between paired sites, supporting structure models and suggesting functional significance. A select set of seven structures were testedin vitrofor their ability to regulate gene expression; all were found to have significant effects. These results indicate potentially widespread roles for RNA structure in posttranscriptional control of human cancer driver genes.
Antimicrobial effect and mechanism of bovine lactoferrin against the potato common scab pathogen Streptomyces scabiei
Authors: Nakamura Masayuki , Tsuda Naoaki , Miyata Takeshi , Ikenaga Makoto
Published: February 2022

Lactoferrin (LF) is a multifunctional protein with a broad spectrum of antimicrobial activities. In this study, we investigated the antimicrobial activity of LF against the potato common scab pathogenStreptomyces scabiei, which causes severe damage to potato tubers. LF derived from bovine (bLF) had much higher activity againstS.scabieithan human LF. The minimal inhibitory concentration of bLF was 3.9 μM. The effects of both apo-bLF (iron-free) and holo-bLF (iron-saturated) onS.scabieiwere not different. Bovine lactoferricin (LFcinB), a short peptide with a length of 25 amino acid residues located in the N-terminal region of bLF, showed antimicrobial activity againstS.scabiei, similar to that of bLF. These results indicated that the antimicrobial activity of bLF againstS.scabieicannot be attributed to its iron-chelating effect but to the bioactivity of its peptides. WhenS.scabieiwas treated with the fusion protein of mCherry-LFcinB (red fluorescent protein) expressed inEscherichia coli, the pseudohyphal cells instantly glowed, indicating that the peptide electrostatically binds to the surface ofS.scabiei. An assay of synthetic peptides, with modified number of arginine (Arg) and tryptophan (Trp) residues based on the antimicrobial center (RRWQWR) of LFcinB showed that Trp residues are implicated in the antimicrobial activity againstS.scabiei; however, Arg residues are also necessary to carry Trp residues to the cell surface to fully exert its activity. Although the single amino acid effect of Trp had low activity, Trp derivatives showed much higher activity againstS.scabiei, suggesting that the derivatives effectively bind to the cell surface (cell membrane) by themselves without a carrier. Thus, amino acid derivatives might be considered effective and alternative antimicrobial substances.